Child Labour: Causes and Impacts

Child tote Causes and ImpactsChild wear is a ball-shaped issue that is becoming increasingly common in current society due to implicating factors such as push law/ employment protection, scantiness, and the economy (i.e. add on and demand for goods and services). Child labour refers to the employment of young volume in jobs that atomic number 18 considered to be illegal and/or exploitive. Including (however non limited to) agriculture, manufacturing, mining and quarrying, prostitution/sexual exploitation and domestic service. This map in which displays the 2014 peasant labour index has data categories ranging between Extreme stake, High Risk, Medium Risk, Low Risk and no data/ not applic adequate. There are concentrations of extreme risk areas across the entire military personnel, centralized in predominantly Northern southward the States i.e. Brazil and Bolivia, Central America i.e. Mexico and Guatemala, The majority of Africa excluding anomalies sparsely scattered on the periphery of Africa (predominantly in the extreme Northern and extreme Southern areas) including South Africa, Libya and Gabon, advertise East Europe, Northern and Southern Asia excluding central countries such as Kazakhstan and Mongolia, and random scatterings in South-East Asia. The top three extreme risk counties in the world are located in the Northeastern periphery of Africa (Eritrea), The Eastern North East periphery of Africa (Somalia) and lastly the core of Africa ( egalitarian republic of Congo). This displays a central clump pattern of extreme risk areas in Africa on a global scale. High-risk zones are scattered randomly across the globe, including inwardly the remainder of South America (the areas that have not already been mentioned as extreme risk), Southern Africa, far Eastern Europe and the remainder of Asia (the areas that have not already been mentioned as extreme risk). Areas that are of low or medium risk include Central and Northern North America, Cent ral and Western Europe, New Zealand and Australia. Lastly on that point are anomalies in which have no data regarding their youngster labour statistics including but not limited to Western Sahara and Greenland. This john be as a resolution of low population and therefore sparse data collection, data censorship, or in terms of slight stintingally authentic countries, not plenteous funding. Overall the pattern is everydayly agglomerated in the core, South-western and North-eastern segments of the map with a holistically dense scattering of child labour across the globe.FactorsPovertyPoverty bottom of the inning be defined as a state of macrocosm extremely poor, having inadequate living necessities such as food, water, shelter, money, goods or means of give. The fussy factor of child labour has helped to shape the pattern of this global issue as displayed through the relation between their patterns. Concentrations of risk for child labour are generally compliant to that of poverty rate, the relation being that as poverty rate increases, so does Child labour risk. With the exception of certain anomalies, which do not comply with the shared general trend of poverty and child, labour e.g. China. The most prominent concentrations of child labour on a global scale can be found in Africa with the top three worst recorded child labour indexs being centralized in Eritrea, Somalia and the Democratic republic of Congo. This relates to multiple independent studies on the poverty rate, which suggest that the proportion of poverty in Sub-Saharan Africa is currently the racyest in the world, therefore showing an fundamental interaction between the three highest risk areas for child labour, and poverty rate. Other global regions poverty statistics (apart from Sub-Saharan Africa) which are displayed in the graph of Extreme Poverty locomote in Every Region of the Developing World include Asia (excluding India), South-Eastern Asia, Eastern Asia (China only) Western Asia, Latin America (and the Caribbean), Sub-Saharan Africa and lastly Northern Africa. All of the regions mentioned for being of the worst poverty rates in the world correspond directly to the concentrations of extreme risk and high risk (high risk being the minority) child labour regions, therefore finalizing the proof of a relationship between poverty and Child labour. Countries that are considered as below the poverty line consist of families within monetary struggle who are unable to obtain a sustainable income and further- more(prenominal) basic living necessities such as sanitation, safe-drinking water, food, and shelter. This wishing of essential human requirements results in a need for alternate finance, which in some cases is then derived from their children. They are forced to expose their children to child labour in order to gain finance to support their families, which shows a direct interaction between poverty and child labour. However there are also other aspects of poverty in which lead to child labour including lack of education. Lack of education being one of the many measures of poverty, which can result in children being used for cheap labour as opposed to gaining an education. Lack of education occurs due to either communal financial struggle meaning that they are unable to fund a schooling organisation or individual financial struggle in which individual families cannot afford to send their children to school which once again results in their children becoming victims of child labour. wear down law/ employment protectionThe labour law/ employment protection within a country is a primary contributor to the pattern of child labour risk globally. This is because a country in which has un protected worker rights, is a country that leaves their citizens helpless against employment exploitation such as child labour. There are a number of independent studies that take indue with regards to employment rights, one of which is carried out by Th e Institute of Global Labour and gracious Rights. This institute acts to investigate employment protection and rights amongst score countries. Developing nations are under scrutiny for their labour laws more so than essential nations as less economically substantial countries tend to be more prone to seeking out cheap labour due to their still developing businesses and corporations. Still developing in the sense that they are a predominantly primary industry meaning that the profit from their efforts in minimal as they are not exchange a final product (which is where the majority of profit is coming in from) and rather are a small part of a larger process. some other reason this study focuses on whether or not less economically developed countries in particular abide by the labour laws in place is because often one of the reasons for a country being less developed is due to government instability which influences enforcement of labour laws. This is because an instable governm ent tends to have less general control over its citizens therefore making them less likely to be able to enforce laws upon civilians and protect the rights of their workers, maximising chance of human rights breach. In the equal breath, bribery is also often present within an instable government meaning that corporations often have the ability to use bribery in exchange for the going of their employment exploitation. Less economically developed regions are located approximately within Latin America, Southern Asia, Far Eastern Europe, and Africa. These regions are all thick clustered with child labour at both high and extreme risk levels, displaying an interaction between the areas under suspicion for labour rights breach and the areas of high/extreme risk of child labour. This therefore shows the implications that labour laws and employment rights can have on child labour, because (as discussed previously) the areas that are less developed are at higher risk of their labour laws being breached due to the requirement for cheap labour amongst developing nations combined with the possibility of government instability which results in lack of protection for workers. However more developed countries such as New Zealand, Australia, and Canada in which have a stable democratic political leaders, have laws lay with the intent of protecting the rights of workers rights, and they have the ability to enforce these laws. These same developed countries are also included in the low risk concentrations of child labour dispersed globally once again displaying the direct interaction between a countries labour laws/ employment rights and the pattern displaying risk of child labour on a global spectrum.EconomyThe economy plays a huge part in shaping the pattern of child labour found globally, the sparsely and dumbly concentrated areas as well as the general dispersal. The success of a world economy can result in child labour in a number of different ways, such as through su pply and demand, and general economic change. The general increase in global economy creates contest between countries in order to produce and sell more goods and services in order to enable economic stability within the country and create more employment opportunities. However this increased magnitude of employment opportunities is one of the factors in which helped to shape the pattern of child labour globally. This is due to the fact that the economic growth occurring in present times in developed countries enhances the demand for goods and services to be produced at a low cost.. The demand for commodities to be produced at a low price is one of the influences of child labour within less economically developed nations. This is because although goods and services are readily accessible to developed countries, they demand for less costly commodities which is produced through one or multiple different less economically developed countries before being exported to a more developed c ountry which then sells it for a far greater profit than what they initially obtained it for, strengthening the economy of already developed nations and depleting the economy of less developed nations. Less economically developed regions are located approximately within Latin America, Southern Asia, Far Eastern Europe, and Africa. These regions are all densely clustered with child labour at both high and extreme risk levels, due to the economic factors previously discussed. However, this is not the only trend that has helped form the global pattern of child labour. Urbanisation is a process, which by extension, can result in a higher risk of child labour. This is because within less developed countries, the population is often self-sufficient or work in independent agricultural businesses. However due to peoples perspectives on the gradual improvement of the economic environment, and the benefits of a paying job versus a self-sufficient farming life, urbanisation rates are increasi ng and people are progressing from being self-sufficient to dependent on an employer and income. However as a result of the ever-changing economic environment, urbanisation is risky as often, due to the fluctuations of economy they risk unemployment, which can lead to poverty and their children being forced into child labour as a result, which displays how the economy with relation to urbanisation, helps shape the pattern of child labour globally.SignificanceEconomicThe signification of child labour on the economy is enormous in terms of the affects that it has on the economy. Despite child labour being a form of modern slavery, which is highly illegal and inhumane, it generally has a positive affect on the global economy. This is because regions in which practice child labour have the ability to greaten their gross domestic product as they are generally producing and exporting commodities at a faster rate and a greater magnitude. This allowing for an economic increase within the c ountries affected by child labour. More economically developed countries also receive economic benefits as a result of child labour as they are able to imports goods at a far cheaper rate than if the commodities had come from a corporation in which pays their workers a higher salary, spends more money on safety precautions, facilities and materials/supplies. This improves the economy, as developed countries are able to spend less money on the imported items and there fore expand to a greater profit margin, further developing their corporations and businesses, economic environment. Although the economic affects of child labour are generally positive, there are negative aspects including the fact that because the products are coming from these primary industries in which have few resources and sparsely educated, pre-adolescent staff, the goods are not always of the same quality/ value that they would have been, had they have been made in better conditions by a more knowledgeable staff . The affect of this lack of quality is that some corporations will opt for a more expensive alternative that tends to last continuing as opposed to buying the products produced by cheap labour, which would ultimately reverse the positive affects of child labour. However this reigns true only for a minority allowing to stop the significance of child labour within the economy in predominantly positive.Social The significance of child labour well-disposedly in terms of a global spectrum can include aspects such as Dehumanisation, Breech of human rights, and the promotion of child exploitation/abuse (especially within families and communities). As a result of child labour, socially, we are dehumanising both the recipients of child labour produced products as well as the children who are being exposed to this form of labour. This is due to the fact that the people who are receiving these products are often knowledgeable of its origins, and still choose to purchase it regardless. Also , children who are working in child labour environments are trapped within a form of modern slavery in which they are forced and obligated to complete work tasks in which are out of the normal social guidelines for their age i.e. getting an education and developing their social skills. This leads to dehumanisation as child labour has changed social regulations in order to make it appropriate to cast out the compassion and sympathy that humans are meant to feel for each other. Another social implication is the fact that child labour is a clear rear of tube of human rights, as any involuntary act that a person is forced to do is against their right as a human-being, as well as the fact that often they are denied their education, social life, and childhood, which is also a breech of their rights. Lastly, the occurrence of child labour promotes exploitation and abuse amongst families and entire communities. Often child labour is caused by parents who send their children into labour du e to the fact that they need the extra salary in order to survive, regardless of this fact, a parent direct their children into child labour is a form a abuse as they are exploiting their children in order to gain finance. The same can be give tongue to for a community who allows child labour to occur, displaying the social significance of child labour on a global spectrum.BibliographyGalli, R. (2001). The Economic impact of child labour. Retrieved whitethorn 3, 2015, from http//www.ilo.org/wcmsp5/groups/public/dgreports/inst/documents/publication/wcms_193680.pdfMultiple authors from ILO, Child Labour. Retrieved whitethorn 3, 2015, from http//www.ilo.org/ipec/facts/langen/index.htmSrivastava, Kalpana. Child Labour Issues and Challenges. Industrial Psychiatry Journal. Medknow Publications Media Pvt Ltd, 2011. Web. 5 May 2015. http//www.ncbi.nlm.nih.gov/pmc/articles/PMC3425238/.Latest Products and Reports. Child Labour Index. Maplecroft, 2013. Web. 2 May 2015. http//maplecroft.com/ portfolio/new-analysis/2013/10/15/child-labour-risks-increase-china-and-russia-most-progress-shown-south-america-maplecroft-index/.Naeem, Zahid, Faiza Shaukat, and Zubair Ahmed. Child Labor in Relation to Poverty. International Journal of Health Sciences. Qassim University, Kingdom of Saudi Arabia, 2011. Web. 2 May 2015. http//www.ncbi.nlm.nih.gov/pmc/articles/PMC3533357/.Varma, Bhakati. Child Labour and Its Impact on Economic Growth. Child Labour and Its Impact on Economic Growth. Slideshare, 2011. Web. 5 May 2015. http//www.slideshare.net/BhaktiVarma/child-labour-and-its-impact-on-economic-growth-9225274.

Underwater Acoustic Sensor Network (UASN)

Under piddle acousticalalal detector Ne iirk (UASN)CHAPTER1 IntroductionMost of the earth start is tranquil of weewee including fresh water from river, lakes etc and salt water from the sea. on that point atomic number 18 still some(prenominal) un-explored aras for such places. This needs signifi merchant shipt research efforts and legal conversation agreements. circulate detector net profit in aqueous medium has the ability to explore the subaqueous purlieu in details. For each applications of submerged, a size qualified communication system as well as an readyive routing protocol is needful. This will enable the subsurface devices to communicate precisely. semiaquatic prolongation speed varies with temperature, saltiness and depth. By varying the subaqueous multiplication speed at different depth, two scenarios ordure be arrive atd accu respectly namely shoal and deep water. shoal water bes of depth less than 200m and cylinder out ventilation . Deep water consists of depth greater or equal to 200 m and spherical spreading. In both sh exclusivelyow and deep water, different ambient incumbrance and different spreading factor is applied.CHAPTER 2 Study of subaquatic acoustic detector mesh analysis situs (UASN) finishing of UASNWireless detector engagement in aqueous medium likewise known as underwater sensing element profit has enabled a broad contrive of applications includingenvironmental monitor semiaquatic sensor meshing can be expend to monitor pollution like chemical, biological such as bring in of tilt or micro-organisms, nuclear and oil leakage pollutions in bays, lakes or rivers 1. Underwater sensor network can also be social functiond to reform support forecast, detect climate change, predict the effect of human activities on marine ecosystems, ocean currents and temperature change e.g. the global warming effect to ocean.Under sea geographic expeditionExploring minerals, oilfields or reservoir, determine routes for laying undersea cables and exploration valuable minerals can be done with such underwater sensor network.Disaster legal professionSensor network that measure seismic activity from remote attitudes can provide tsunami warning to coastal atomic number 18as, or study the effects of submarine earthquakes (seaquakes) 2Equipment Monitoringsemipermanent equipment monitor whitethorn be done with pre-installed infrastructure. Short-term equipment monitoring shargons many requirements of long-term seismic monitoring, including the need for fit outless (acoustic) communication, automatic configuration into a multihop network, position (and hence time synchronization), and energy efficient operationMine ReconnaissanceBy using acoustic sensors and optical sensors together, mine sensing can be accomplished quickly and effectively.Assisted MonitoringSensor can be used to discoer danger on the seabed, locate dangerous rocks or shoals in shallow waters, mooring positio n, submerged wrecks and to perform bathymetry profiling.Information collectionThe main goal of communication network is the exchange of reading in spite of appearance the network and outside the network via a gateway or switch center. This application is used to sh be information among nodes and autonomous underwater vehicles.Characteristic of UASNUnderwater Acoustic Net kit and boodle (UANs), including but non exceptional to, Underwater Acoustic Sensor Networks (UASNs) and Autonomous Underwater Vehicle Networks (AUVNs) , atomic number 18 defined as networks composed of more(prenominal)(prenominal) than two nodes, using acoustic orients to communicate, for the intend of underwater applications. UASNs and AUVNs atomic number 18 two important kinds of UANs. The former is composed of many sensor nodes, mostly for a monitoring purpose. The nodes atomic number 18 unremarkably without or with bound capacity to move. The latter is composed of autonomous or unmanned vehicles w ith in racy spirits mobility, deployed for applications that need mobility, e.g., exploration. An UAN can be an UASN, or an AUVN, or a combination of both.Acoustic communications, on the other hands, is defined as communication methods from one point to a nonher by using acoustic omens. Network structure is not formed in acoustic point-to-point communications.Sound travels best through the water in comparison with electromagnetic waves and optical signals. Acoustic signal is sound signal waveform, normally produced by sonar for underwater applications. Acoustic signal processing extracts information from acoustic signals in the presence of encumbrance and uncertainty.Underwater acoustic communications are generally ope rund by path wrong, noise, multi-path, Doppler spread, and high and variable propagation check over. All these factors determine the temporal and spatial division of the acoustic stock, and make the available bandwidth of the Underwater Acoustic line (UW- A) bound and dramatically dependent on both effigy and absolute absolute frequency. Long-range systems that operate over several(prenominal)(prenominal) tens of kilometers may vex a bandwidth of only a few kHz, while a short-range system operating(a) over several tens of meters may acquire more than a coulomb kHz bandwidth. These factors lead to low bit rate.Underwater acoustic communication concerns can be categorize match to their range as very long, long, medium, short, and very short links. Acoustic links are also roughly classified as vertical and horizontal, correspond to the didactics of the sound ray. Their propagation characteristics differ consistently, especially with respect to time dispersion, multi-path spreads, and go over variance.Acoustic signal is the only physical feasible tool that works in underwater environment. Compared with it, electromagnetic wave can only travel in water with short distance callable to the high attenuation and engrossment e ffect in underwater environment. It is found that the absorption of electromagnetic energy in sea water is about 45 ?f dB per kilometer, where f is frequency in Hertz In contrast, the absorption of acoustic signal over most frequencies of interest is about three invests of magnitude lower 40. future tense the factors that influence acoustic communications is analyzed in put together to state the challenges posed by the underwater courses for underwater sensor networking. These include highroad lossAttenuation is principally provoked by absorption due to conversion of acoustic energy into heat, which increases with distance and frequency. It is also caused by scattering a reverberation (on rough ocean get on and lowlife), refraction, and dispersion (due to the displacement of the reflection point caused by wind on the surface). Water depth plays a recognise fiber in determining the attenuation.Geometric Spreading is the spreading of sound energy as a result of the expansion o f the wavefronts. It increases with the propagation distance and is free lance of frequency. There are two normal kinds of geometric spreading spherical (omni-directional point arising), and cylindrical (horizontal radiation only). interferenceMan made noise is mainly caused by machinery noise (pumps, reduction gears, power plants, etc.), and shipping activity (hull fouling, animal life on hull, cavitations), especially in areas encumbered with heavy vessel traffic.ambient Noise is related to hydrodynamics (movement of water including tides, current, storms, wind, rain, etc.), seismic and biological phenomena.Multi-pathMulti-path propagation may be responsible for severe degradation of the acoustic communication signal, since it generates Inter-Symbol onus (ISI).The multi-path geometry depends on the link configuration. Vertical avenues are characterized by little time dispersion, whereas horizontal channels may have totally long multi-path spreads.The goal of the spreading i s a strong function of depth and the distance between transmitter and telephone receiver.High wait and delay varianceThe propagation speed in the UW-A channel is five orders of magnitude lower than in the wireless channel. This outsized propagation delay (0.67 s/km) can reduce the throughput of the system considerably.The very high delay variance is even more harmful for efficient protocol design, as it delays from accurately estimating the round trip time (RTT), which is the key parameter for many common communication protocols.Doppler spreadThe Doppler frequency spread can be significant in UW-A channels, causing degradation in the performance of digital communications transmittals at a high information rate because many adjacent symbols to interfere at the receiver, requiring sophisticated signal processing to deal with the generated ISI.The Doppler spreading generatesa simple(a) frequency translation, which is relatively easy for a receiver to continue fora continuous spreading of frequencies, which constitutes a non-shifted signal, which is more difficult for a receiver to treat for.If a channel has a Doppler spread with bandwidth B and a signal has symbol duration T, then there are approximately BT uncorrelated samples of its interlacing envelope. When BT is much less than unity, the channel is said to be under spread and the effects of the Doppler fading can be ignored, while, if greater than unity, it is overspread.Most of the set forth factors are caused by the chemical-physical properties of the water medium such as temperature, salinity and density, and by their spatio-temporal variations. These variations, together with the wave guide nature of the channel, because the acoustic channel to be temporally and spatially variable. In particular, the horizontal channel is by far more rapidly varying than the vertical channel, in both deep and shallow water.CHAPTER 3 Network ArchitectureUnderwater sensor nodes The underwater sensor nodes are deployed on the sea floor anchored to the ocean laughingstock 32. The sensors are equipped with floating(a) buoys to push the nodes upwards, thus they are relatively stationary nodes 3. Using acoustic links, they relay info to underwater drop off directly or via multi-hop path.Underwater get back nodes Underwater fall away nodes take charge of collecting entropy of underwater sensors deployed on the ocean bottom and then send to the surface sink node. They may be equipped with vertical and horizontal acoustic transducers. The horizontal transceiver is used to collect the sensors data and the vertical transceiver provides transmitting link between underwater sink and the surface sink node.Surface sink node Surface sink node is attached on a floating buoy with satellite, radio frequency (RF) or cell phone technology to transmit data to shore in real time.2D ModelA reference architecture for two-dimensional underwater networks is shown in Figure. 1. A group of sensor nodes ar e anchored to the deep of the ocean. Underwater sensor nodes are interconnected to one or more underwater gateways by means of wireless acoustic links. Underwater-gateways are network devices in charge of relaying data from the ocean bottom network to a surface station. To accomplish this objective, they are equipped with two acoustic transceivers, namely a vertical and a horizontal transceiver. The horizontal transceiver is used by the underwater-gateway to communicate with the sensor nodes in order tosend commands and configuration data to the sensors (underwater -gateway to sensors)collect monitored data (sensors to underwater -gateway). The vertical link is used by the underwater -gateways to relay data to a surface station.In deep water applications, vertical transceivers must be long range transceivers. The surface station is equipped with an acoustic transceiver that is able to cover up ninefold parallel communications with the deployed underwater -gateways. It is also end owed with a long range RF and/or satellite transmitter to communicate with the shoreward sink (os-sink) and/or to a surface sink (s-sink). In shallow water, bottom-deployed sensors/modems may directly communicate with the surface buoy, with no specialized bottom node (underwater -gateway).3D ModelThree-dimensional underwater networks are used to detect and find out phenomena that cannot be adequately observed by means of ocean bottom sensor nodes, i.e., to perform cooperative sampling of the 3D ocean environment. In three-dimensional underwater networks, sensor nodes float at different depths to observe a phenomenon. In this architecture, given in Figure 2, each sensor is anchored to the ocean bottom and equipped with a floating buoy that can be blow up by a pump. The buoy pushes the sensor towards the ocean surface. The depth of the sensor can then be regulated by adjusting the length of the wire that connects the sensor to the anchor, by means of an electronically reignled eng ine that resides on the sensor. Sensing and communication coverage in a 3D environment are purely investigated in 8. The diameter, minimum and maximum degree of the reachability graph that describes the network are derived as a function of the communication range, while different degrees of coverage for the 3D environment are characterized as a function of the sensing range.3D Model with AUVThe above figure represents the third type of network architecture which consist of sensor nodes and Autonomous Underwater Vehicles (AUV) which act as mobile sensor nodes for ocean monitoring, underwater resource study, etc.CHAPTER 4 Differences between underwater and sublunary Sensor NetworkAn underwater acoustic channel is different from a ground-based radio channel from many aspects, includingBandwidth is passing limited. The attenuation of acoustic signal increases with frequency and range 6 10. Consequently, the feasible band is extremely small. For example, a short range system operatin g over several tens of meters may have available bandwidth of a hundred kHz a medium-range system operating over several kilometers has a bandwidth on the order of ten kHz and a long-range system operating over several tens of kilometers is limited to only a few kHz of bandwidth 11.Propagation delay is long. The transmitting speed of acoustic signals in engaging water is around 1500 meter/s 22, which is a difference of five orders of magnitude lower than the speed of electromagnetic wave in free space. Correspondently, propagation delay in an underwater channel becomes significant. This is one of the essential characteristics of underwater channels and has profound implications on localization and time synchronization.The channel impulse reaction is not only spatially varied but also temporarily varied. The channel characteristics vary with time and highly depend on the location of the transmitter and receiver. The vacillation nature of the channel causes the received signals eas ily distorted. There are two types of propagation paths macro-multipaths, which are the deterministic propagation paths and micro-multipath, which is a stochastic signal fluctuation. The macro-multipaths are caused by both reflection at the boundaries (bottom, surface and any object in the water) and bending. Inter- Symbol Interference (ISI) thus occurs. Compared with the spread of its ground-based counterpart, which is on the order of several symbol intervals, ISI spreading in an underwater acoustic channel is several tens or hundred of symbol intervals for moderate to high data rate in the horizontal channel. Micro-multipath fluctuations are mainly caused by surface wave, which contributes the most to the time variability of shallow water channel.In deep water, internal waves tinct the single-path random fluctuations 1213.Probability of bit phantasm is much high and temporary loss of connectivity (shadow zone) some generation occurs, due to the extreme characteristics of the c hannel.Cost. era worldwide sensor nodes are pass judgment to become increasingly inexpensive, underwater sensors are expensive devices. This is especially due to the more complex underwater transceivers and to the hardware protection needed in the extreme underwater environment. Also, because of the low economy of scale caused by a small relative number of suppliers, underwater sensors are characterized by high cost.Deployment. piece terrestrial sensor networks are densely deployed, in underwater, the deployment is generally more sparse.Power. The power needed for acoustic underwater communications is high than in terrestrial radio communications because of the different physical form technology (acoustic vs. RF waves), the higher distances, and more complex signal processing techniques implemented at the receivers to compensate for the impairments of the channel.Memory. While terrestrial sensor nodes have very limited storage capacity, underwater-sensors may need to be able t o do some data caching as the underwater channel may be intermittent.Spatial Correlation. While the readings from terrestrial sensors are often correlated, this is more un in all likelihood to happen in underwater networks due to the higher distance among sensors.CHAPTER 5 Layered of UASNThe underwater architecture network consists of five floors, application, hex, network, data link and physical stage as shown in the figure below. As typical underwater systems have limited processing capacity, the protocol has been kept as simple as possible without significantly compromising performance.The underwater sensor network specifications currently do not include any recommendations for authentication and encryption. These may be easily implemented at the application layer or via a spreading scheme at the physical layer.Each layer is described by a SAPI. The SAPI is defined in terms of communicates universe passed to and from the layer. The clients (usually higher layers) of a layer invoke the layer via a request (REQ). The layer responds to each REQ by a response (RSP). Errors are reported via an drift RSP with geological fault canons. If the layer needs to send unsolicited sums to the client, it does so via a notification (NTF). A layer communicates logically with its peer layer via protocol data units (PDU). As the peer-to-peer communication is symmetric, a layer may send a REQ PDU to its peer layer at any time. It would optionally respond to such a PDU with a RSP PDU. This is logically depicted in Figure belowIt may be desirable in some cases, that non-neighboring layers communicate with each other to achieve cross-layer optimization. This may be implemented by allowing REQ and RSP PDUs between any two layers in the protocol stack.The underwater sensor network specifications define detailed message structures for all SAPI messages. These message structures include message identifiers, data formats to be used, parameters and their possible valuesPhysical layerThe physical layer provides framing, inflexion and error bailiwick capability (via FEC). It provides primitives for sending and receiving piles. It may also provide additional functionality such as parameter settings, parameter recommendation, holder sensing, etc.At first underwater channel development was based on non- pellucid frequency shift keying (FSK) modulation, since it relies on energy detection. Thus, it does not require physical body tracking, which is a very difficult parturiency mainly because of the Doppler-spread in the underwater acoustic channel. Although non-coherent modulation schemes are characterized by high power efficiency, their low bandwidth efficiency makes them unsui display board for high data rate multiuser networks.Hence, coherent modulation techniques have been developed for long-range, high-throughput systems. In the last years, fully coherent modulation techniques, such as phase shift keying (PSK) and quadrature amplitude modulation (QAM) , have become practical due to the availability of powerful digital processing. Channel equalization techniques are exploited to leverage the effect of the inter-symbol interference (ISI), or else of attempt to avoid or suppress it. Decision-feedback equalizers (DFEs) track the complex, relatively slow varying channel response and thus provide high throughput when the channel is slowly varying. Conversely, when the channel varies faster, it is necessary to combine the DFE with a Phase Locked Loop (PLL) 9, which estimates and compensates for the phase offset in a rapid, stable manner. The use of decision feedback equalization and phase-locked loops is dictated by the complexity and time variability of ocean channel impulse responses.Differential phase shift keying (DPSK) serves as an intermediate solution between unlogical and fully coherent systems in terms of bandwidth efficiency. DPSK encodes information relative to the previous symbol rather than to an arbitrary fixed refere nce in the signal phase and may be referred to as a partially coherent modulation. While this strategy substantially alleviates carrier phase-tracking requirements, the penalty is an change magnitude error probability over PSK at an equivalent data rate.Another promising solution for underwater communications is the sassy frequency member multiplexing (OFDM) spread spectrum technique, which is particularly efficient when noise is spread over a large portion of the available bandwidth. OFDM is frequently referred to as multicarrier modulation because it transmits signals over multiple sub-carriers simultaneously. In particular, sub-carriers that experience higher SNR, are dispense with a higher number of bits, whereas less bits are allotted to sub-carriers experiencing attenuation, according to the concept of bit loading, which requires channel estimation. Since the symbol duration for each soul carrier increases, OFDM systems perform robustly in severe multi-path environments, and achieve a high spectral efficiency.Many of the techniques discussed above require underwater channel estimation, which can be achieved by means of probe packets 17. An accurate estimate of the channel can be obtained with a high probing rate and/or with a large probe packet size, which however result in high overhead, and in the consequent drain of channel capacity and energy.Data link layer (MAC layer)The data link layer provides single hop data transmission capability it will not be able to transmit a packet successfully if the destination node is not directly entrance feeible from the source node. It may include some degree of reliability. It may also provide error detection capability (e.g. CRC check). In case of a shared medium, the data link layer must include the medium access control (MAC) sub-layer. oftenness division multiple access (FDMA) is not suitable for underwater sensor network due to the narrow bandwidth in underwater acoustic channels and the pic of limited band systems to fading and multipath.Time division multiple access (TDMA) shows limited bandwidth efficiency because of the long time fortresss postulate in the underwater acoustic channel. In fact, long time guards must be designed to account for the large propagation delay and delay variance of the underwater channel in order to minimize packet collisions from adjacent time slots. Moreover, the variable delay makes it very challenging to realize a precise synchronization, with a common clock reference, which is required for TDMA.Carrier sense multiple access (CSMA) prevents collisions with the ongoing transmission at the transmitter side. To prevent collisions at the receiver side, however, it is necessary to add a guard time between transmissions dimensioned according to the maximum propagation delay in the network. This makes the protocol dramatically inefficient for underwater acoustic sensor network.The use of contention-based techniques that swear on handshaking mechanisms such as RTS/ CTS in shared medium access is impractical in underwater, for the following reasonslarge delays in the propagation of RTS/CTS control packets lead to low throughputdue to the high propagation delay of underwater acoustic channels, when carrier sense is used, as in 802.11, it is more likely that the channel be sensed idle while a transmission is ongoing, since the signal may not have reached the receiver yetthe high variability of delay in handshaking packets makes it impractical to predict the start and finish time of the transmissions of other stations. Thus, collisions are highly likely to occur.Code division multiple access (CDMA) is quite robust to frequency selective fading caused by underwater multi-paths, since it distinguishes simultaneous signals transmitted by multiple devices by means of pseudo-noise codes that are used for spreading the user signal over the entire available band. CDMA allows reducing the number of packet retransmissions, which results in f lowd battery consumption and increased network throughput.In conclusion, although the high delay spread which characterizes the horizontal link in underwater channels makes it difficult to maintain synchronization among the stations, especially when orthogonal code techniques are used 17, CDMA is a promising multiple access technique for underwater acoustic networks. This is particularly true in shallow water, where multi-paths and Doppler- spreading plays a key role in the communication performance.Network layer (Routing)The network layer is in charge of determining the path between a source (the sensor that samples a physical phenomenon) and a destination node (usually the surface station). In general, while many impairments of the underwater acoustic channel are adequately turn to at the physical and data link layers, some other characteristics, such as the extremely long propagation delays, are split up addressed at the network layer.Basically, there are two methods of routing . The first one is virtual band routing and the second one is packet-switch routing.In virtual circuit routing, the networks use virtual circuits to decide on the path at the beginning of the network operation. Virtual-circuit-switch routing protocols can be a better choice for underwater acoustic networks. The reasons areUnderwater acoustic networks are typical asymmetric instead of symmetric. However, packet switched routing protocols are proposed for symmetric network architectureVirtual-circuit-switch routing protocols work robust against link failure, which is critical in underwater environment andVirtual-circuit-switch routing protocols have less signal overhead and low rotational latency, which are needed for underwater acoustic channel environment.However, virtual-circuit-switch routing protocols usually omit of flexibility.In packet-switch routing, every node that is part of the transmission makes its own routing decision, i.e., decides its next hop to relay the packet. Packet-switch routing can be further classified into proactive routing, oxidizable and geographical routing protocols. Most routing protocols for ground-based wireless networks are packet-switch based.Proactive routing protocols attempt to minimize the message latency by maintaining up-to-date routing information at all times from each node to any other node. It broadcasts control packets that contain routing table information. Typical protocols include Destination Sequence Distance vector (DSDV) 28 and temporally arranged Routing Algorithm (TORA).However, proactive routing protocols provoke a large signaling overhead to establish routes for the first time and each time the network topology changes. It may not be a good fit in underwater environment due to the high probability of link failure and extremely limited bandwidth there.Reactive routing protocols only initiate a route discovery process upon request. Correspondently, each node does not need to maintain a respectable lo ok-up table for routing. This kind of routing protocols is more suitable for dynamic environment like ad hoc wireless networks. Typical protocol examples are Ad hoc On-demand Distance Vector (AODV) 23, and high-powered Source Routing (DSR) 27.The shortage of reactive routing protocols is its high latency to establish routing. Similar to its proactive counterpart, flooding of control packets to establish paths is needed, which brings significant signal overhead. The high latency could become much deteriorated in underwater environment because of the much slower propagation speed of acoustic signal compared with the radio wave in the air.geographic routing (also called georouting or position-based routing) is a routing principle that relies on geographic position information. It is mainly proposed for wireless networks and based on the idea that the source sends a message to the geographic location of the destination instead of using the network address.Geographic routing requires th at each node can determine its own location and that the source is advised of the location of the destination. With this information a message can be routed to the destination without knowledge of the network topology or a prior route discovery. fare layerA transport layer protocol is needed in underwater sensor network not only to achieve reliable corporal transport of event features, but also to perform flow control and congestion control. The primary objective is to save scarce sensor resources and increase the network efficiency. A reliable transport protocol should guarantee that the applications be able to correctly identify event features estimated by the sensor network. Congestion control is needed to prevent the network from being congested by excessive data with respect to the network capacity, while flow control is needed to avoid that network devices with limited memory are overwhelmed by data transmissions.Most existing TCP implementations are unsuited for the underwa ter environment, since the flow control functionality is based on a window- based mechanism that relies on an accurate esteem of the round trip time (RTT), which is twice the end-to-end delay from source to destination.Rate-based transport protocols count also unsuited for this challenging environment. They still rely on feedback control messages sent back by the destination to dynamically adapt the transmission rate, i.e., to decrease the transmission rate when packet loss is experienced or to increase it otherwise. The high delay and delay variance can thus cause dissymmetry in the feedback control.Furthermore, due to the unreliability of the acoustic channel, it is necessary to distinguish between packet losses due to the high bit error rate of the acoustic channel, from those caused by packets being dropped from the queues of sensor nodes due to network congestion. In terrestrial, assume that congestion is the only cause for packet loss and the solution lies on change magnitud e the transmission rate, but in underwater sensor network if the packet loss is due to bad channel then the transmission rate should not be decreased to preserve throughput efficiency.Transport layer functionalities can be tightly integrated with data link layer functionalities in a cross-layer module. The purpose of such an integrated module is to make the information about the condition of the variable underwater channel available also at the transport layer. In fact, usually the state of the channel is known only at the physical and channel access sub-layers, while the design principle of layer separation makes this information unreserved to the higher layers. This integration allows maximizing theUnderwater Acoustic Sensor Network (UASN)Underwater Acoustic Sensor Network (UASN)CHAPTER1 IntroductionMost of the earth surface is composed of water including fresh water from river, lakes etc and salt water from the sea. There are still many un-explored areas for such places. This ne eds significant research efforts and good communication systems. Wireless sensor network in aqueous medium has the ability to explore the underwater environment in details. For all applications of underwater, a good communication system as well as an effective routing protocol is needed. This will enable the underwater devices to communicate precisely. Underwater propagation speed varies with temperature, salinity and depth. By varying the underwater propagation speed at different depth, two scenarios can be achieved accurately namely shallow and deep water. Shallow water consists of depth less than 200m and cylinder spreading. Deep water consists of depth greater or equal to 200 m and spherical spreading. In both shallow and deep water, different ambient noise and different spreading factor is applied.CHAPTER 2 Study of Underwater Acoustic Sensor Network (UASN)Application of UASNWireless sensor network in aqueous medium also known as underwater sensor network has enabled a broad ra nge of applications includingEnvironmental MonitoringUnderwater sensor network can be used to monitor pollution like chemical, biological such as tracking of fish or micro-organisms, nuclear and oil leakage pollutions in bays, lakes or rivers 1. Underwater sensor network can also be used to improve weather forecast, detect climate change, predict the effect of human activities on marine ecosystems, ocean currents and temperature change e.g. the global warming effect to ocean.Under Ocean ExplorationExploring minerals, oilfields or reservoir, determine routes for laying undersea cables and exploration valuable minerals can be done with such underwater sensor network.Disaster PreventionSensor network that measure seismic activity from remote locations can provide tsunami warning to coastal areas, or study the effects of submarine earthquakes (seaquakes) 2Equipment MonitoringLong-term equipment monitoring may be done with pre-installed infrastructure. Short-term equipment monitoring sha res many requirements of long-term seismic monitoring, including the need for wireless (acoustic) communication, automatic configuration into a multihop network, localization (and hence time synchronization), and energy efficient operationMine ReconnaissanceBy using acoustic sensors and optical sensors together, mine detection can be accomplished quickly and effectively.Assisted MonitoringSensor can be used to discover danger on the seabed, locate dangerous rocks or shoals in shallow waters, mooring position, submerged wrecks and to perform bathymetry profiling.Information collectionThe main goal of communication network is the exchange of information inside the network and outside the network via a gateway or switch center. This application is used to share information among nodes and autonomous underwater vehicles.Characteristic of UASNUnderwater Acoustic Networks (UANs), including but not limited to, Underwater Acoustic Sensor Networks (UASNs) and Autonomous Underwater Vehicle Ne tworks (AUVNs) , are defined as networks composed of more than two nodes, using acoustic signals to communicate, for the purpose of underwater applications. UASNs and AUVNs are two important kinds of UANs. The former is composed of many sensor nodes, mostly for a monitoring purpose. The nodes are usually without or with limited capacity to move. The latter is composed of autonomous or unmanned vehicles with high mobility, deployed for applications that need mobility, e.g., exploration. An UAN can be an UASN, or an AUVN, or a combination of both.Acoustic communications, on the other hands, is defined as communication methods from one point to another by using acoustic signals. Network structure is not formed in acoustic point-to-point communications.Sound travels best through the water in comparison with electromagnetic waves and optical signals. Acoustic signal is sound signal waveform, usually produced by sonar for underwater applications. Acoustic signal processing extracts inform ation from acoustic signals in the presence of noise and uncertainty.Underwater acoustic communications are mainly influenced by path loss, noise, multi-path, Doppler spread, and high and variable propagation delay. All these factors determine the temporal and spatial variability of the acoustic channel, and make the available bandwidth of the Underwater Acoustic channel (UW-A) limited and dramatically dependent on both range and frequency. Long-range systems that operate over several tens of kilometers may have a bandwidth of only a few kHz, while a short-range system operating over several tens of meters may have more than a hundred kHz bandwidth. These factors lead to low bit rate.Underwater acoustic communication links can be classified according to their range as very long, long, medium, short, and very short links. Acoustic links are also roughly classified as vertical and horizontal, according to the direction of the sound ray. Their propagation characteristics differ consist ently, especially with respect to time dispersion, multi-path spreads, and delay variance.Acoustic signal is the only physical feasible tool that works in underwater environment. Compared with it, electromagnetic wave can only travel in water with short distance due to the high attenuation and absorption effect in underwater environment. It is found that the absorption of electromagnetic energy in sea water is about 45 ?f dB per kilometer, where f is frequency in Hertz In contrast, the absorption of acoustic signal over most frequencies of interest is about three orders of magnitude lower 40.Hereafter the factors that influence acoustic communications is analyzed in order to state the challenges posed by the underwater channels for underwater sensor networking. These includePath lossAttenuation is mainly provoked by absorption due to conversion of acoustic energy into heat, which increases with distance and frequency. It is also caused by scattering a reverberation (on rough ocean s urface and bottom), refraction, and dispersion (due to the displacement of the reflection point caused by wind on the surface). Water depth plays a key role in determining the attenuation.Geometric Spreading is the spreading of sound energy as a result of the expansion of the wavefronts. It increases with the propagation distance and is independent of frequency. There are two common kinds of geometric spreading spherical (omni-directional point source), and cylindrical (horizontal radiation only).NoiseMan made noise is mainly caused by machinery noise (pumps, reduction gears, power plants, etc.), and shipping activity (hull fouling, animal life on hull, cavitations), especially in areas encumbered with heavy vessel traffic.Ambient Noise is related to hydrodynamics (movement of water including tides, current, storms, wind, rain, etc.), seismic and biological phenomena.Multi-pathMulti-path propagation may be responsible for severe degradation of the acoustic communication signal, sinc e it generates Inter-Symbol Interference (ISI).The multi-path geometry depends on the link configuration. Vertical channels are characterized by little time dispersion, whereas horizontal channels may have extremely long multi-path spreads.The extent of the spreading is a strong function of depth and the distance between transmitter and receiver.High delay and delay varianceThe propagation speed in the UW-A channel is five orders of magnitude lower than in the radio channel. This large propagation delay (0.67 s/km) can reduce the throughput of the system considerably.The very high delay variance is even more harmful for efficient protocol design, as it prevents from accurately estimating the round trip time (RTT), which is the key parameter for many common communication protocols.Doppler spreadThe Doppler frequency spread can be significant in UW-A channels, causing degradation in the performance of digital communications transmissions at a high data rate because many adjacent symbo ls to interfere at the receiver, requiring sophisticated signal processing to deal with the generated ISI.The Doppler spreading generatesa simple frequency translation, which is relatively easy for a receiver to compensate fora continuous spreading of frequencies, which constitutes a non-shifted signal, which is more difficult for a receiver to compensate for.If a channel has a Doppler spread with bandwidth B and a signal has symbol duration T, then there are approximately BT uncorrelated samples of its complex envelope. When BT is much less than unity, the channel is said to be under spread and the effects of the Doppler fading can be ignored, while, if greater than unity, it is overspread.Most of the described factors are caused by the chemical-physical properties of the water medium such as temperature, salinity and density, and by their spatio-temporal variations. These variations, together with the wave guide nature of the channel, because the acoustic channel to be temporally and spatially variable. In particular, the horizontal channel is by far more rapidly varying than the vertical channel, in both deep and shallow water.CHAPTER 3 Network ArchitectureUnderwater sensor nodes The underwater sensor nodes are deployed on the sea floor anchored to the ocean bottom 32. The sensors are equipped with floating buoys to push the nodes upwards, thus they are relatively stationary nodes 3. Using acoustic links, they relay data to underwater sink directly or via multi-hop path.Underwater sink nodes Underwater sink nodes take charge of collecting data of underwater sensors deployed on the ocean bottom and then send to the surface sink node. They may be equipped with vertical and horizontal acoustic transducers. The horizontal transceiver is used to collect the sensors data and the vertical transceiver provides transmitting link between underwater sink and the surface sink node.Surface sink node Surface sink node is attached on a floating buoy with satellite, radio frequency (RF) or cell phone technology to transmit data to shore in real time.2D ModelA reference architecture for two-dimensional underwater networks is shown in Figure. 1. A group of sensor nodes are anchored to the deep of the ocean. Underwater sensor nodes are interconnected to one or more underwater gateways by means of wireless acoustic links. Underwater-gateways are network devices in charge of relaying data from the ocean bottom network to a surface station. To achieve this objective, they are equipped with two acoustic transceivers, namely a vertical and a horizontal transceiver. The horizontal transceiver is used by the underwater-gateway to communicate with the sensor nodes in order tosend commands and configuration data to the sensors (underwater -gateway to sensors)collect monitored data (sensors to underwater -gateway). The vertical link is used by the underwater -gateways to relay data to a surface station.In deep water applications, vertical transceivers must be lon g range transceivers. The surface station is equipped with an acoustic transceiver that is able to handle multiple parallel communications with the deployed underwater -gateways. It is also endowed with a long range RF and/or satellite transmitter to communicate with the onshore sink (os-sink) and/or to a surface sink (s-sink). In shallow water, bottom-deployed sensors/modems may directly communicate with the surface buoy, with no specialized bottom node (underwater -gateway).3D ModelThree-dimensional underwater networks are used to detect and observe phenomena that cannot be adequately observed by means of ocean bottom sensor nodes, i.e., to perform cooperative sampling of the 3D ocean environment. In three-dimensional underwater networks, sensor nodes float at different depths to observe a phenomenon. In this architecture, given in Figure 2, each sensor is anchored to the ocean bottom and equipped with a floating buoy that can be inflated by a pump. The buoy pushes the sensor towa rds the ocean surface. The depth of the sensor can then be regulated by adjusting the length of the wire that connects the sensor to the anchor, by means of an electronically controlled engine that resides on the sensor. Sensing and communication coverage in a 3D environment are rigorously investigated in 8. The diameter, minimum and maximum degree of the reachability graph that describes the network are derived as a function of the communication range, while different degrees of coverage for the 3D environment are characterized as a function of the sensing range.3D Model with AUVThe above figure represents the third type of network architecture which consist of sensor nodes and Autonomous Underwater Vehicles (AUV) which act as mobile sensor nodes for ocean monitoring, underwater resource study, etc.CHAPTER 4 Differences between underwater and terrestrial Sensor NetworkAn underwater acoustic channel is different from a ground-based radio channel from many aspects, includingBandwidth is extremely limited. The attenuation of acoustic signal increases with frequency and range 6 10. Consequently, the feasible band is extremely small. For example, a short range system operating over several tens of meters may have available bandwidth of a hundred kHz a medium-range system operating over several kilometers has a bandwidth on the order of ten kHz and a long-range system operating over several tens of kilometers is limited to only a few kHz of bandwidth 11.Propagation delay is long. The transmission speed of acoustic signals in salty water is around 1500 meter/s 22, which is a difference of five orders of magnitude lower than the speed of electromagnetic wave in free space. Correspondently, propagation delay in an underwater channel becomes significant. This is one of the essential characteristics of underwater channels and has profound implications on localization and time synchronization.The channel impulse response is not only spatially varied but also temporarily varied. The channel characteristics vary with time and highly depend on the location of the transmitter and receiver. The fluctuation nature of the channel causes the received signals easily distorted. There are two types of propagation paths macro-multipaths, which are the deterministic propagation paths and micro-multipath, which is a random signal fluctuation. The macro-multipaths are caused by both reflection at the boundaries (bottom, surface and any object in the water) and bending. Inter- Symbol Interference (ISI) thus occurs. Compared with the spread of its ground-based counterpart, which is on the order of several symbol intervals, ISI spreading in an underwater acoustic channel is several tens or hundred of symbol intervals for moderate to high data rate in the horizontal channel. Micro-multipath fluctuations are mainly caused by surface wave, which contributes the most to the time variability of shallow water channel.In deep water, internal waves impact the single-path ra ndom fluctuations 1213.Probability of bit error is much higher and temporary loss of connectivity (shadow zone) sometimes occurs, due to the extreme characteristics of the channel.Cost. While terrestrial sensor nodes are expected to become increasingly inexpensive, underwater sensors are expensive devices. This is especially due to the more complex underwater transceivers and to the hardware protection needed in the extreme underwater environment. Also, because of the low economy of scale caused by a small relative number of suppliers, underwater sensors are characterized by high cost.Deployment. While terrestrial sensor networks are densely deployed, in underwater, the deployment is generally more sparse.Power. The power needed for acoustic underwater communications is higher than in terrestrial radio communications because of the different physical layer technology (acoustic vs. RF waves), the higher distances, and more complex signal processing techniques implemented at the recei vers to compensate for the impairments of the channel.Memory. While terrestrial sensor nodes have very limited storage capacity, underwater-sensors may need to be able to do some data caching as the underwater channel may be intermittent.Spatial Correlation. While the readings from terrestrial sensors are often correlated, this is more unlikely to happen in underwater networks due to the higher distance among sensors.CHAPTER 5 Layered of UASNThe underwater architecture network consists of five layers, application, transport, network, data link and physical layer as shown in the figure below. As typical underwater systems have limited processing capability, the protocol has been kept as simple as possible without significantly compromising performance.The underwater sensor network specifications currently do not include any recommendations for authentication and encryption. These may be easily implemented at the application layer or via a spreading scheme at the physical layer.Each l ayer is described by a SAPI. The SAPI is defined in terms of messages being passed to and from the layer. The clients (usually higher layers) of a layer invoke the layer via a request (REQ). The layer responds to each REQ by a response (RSP). Errors are reported via an ERR RSP with error codes. If the layer needs to send unsolicited messages to the client, it does so via a notification (NTF). A layer communicates logically with its peer layer via protocol data units (PDU). As the peer-to-peer communication is symmetric, a layer may send a REQ PDU to its peer layer at any time. It would optionally respond to such a PDU with a RSP PDU. This is logically depicted in Figure belowIt may be desirable in some cases, that non-neighboring layers communicate with each other to achieve cross-layer optimization. This may be implemented by allowing REQ and RSP PDUs between any two layers in the protocol stack.The underwater sensor network specifications define detailed message structures for all SAPI messages. These message structures include message identifiers, data formats to be used, parameters and their possible valuesPhysical layerThe physical layer provides framing, modulation and error correction capability (via FEC). It provides primitives for sending and receiving packets. It may also provide additional functionality such as parameter settings, parameter recommendation, carrier sensing, etc.At first underwater channel development was based on non-coherent frequency shift keying (FSK) modulation, since it relies on energy detection. Thus, it does not require phase tracking, which is a very difficult task mainly because of the Doppler-spread in the underwater acoustic channel. Although non-coherent modulation schemes are characterized by high power efficiency, their low bandwidth efficiency makes them unsuitable for high data rate multiuser networks.Hence, coherent modulation techniques have been developed for long-range, high-throughput systems. In the last years, fully coherent modulation techniques, such as phase shift keying (PSK) and quadrature amplitude modulation (QAM), have become practical due to the availability of powerful digital processing. Channel equalization techniques are exploited to leverage the effect of the inter-symbol interference (ISI), instead of trying to avoid or suppress it. Decision-feedback equalizers (DFEs) track the complex, relatively slowly varying channel response and thus provide high throughput when the channel is slowly varying. Conversely, when the channel varies faster, it is necessary to combine the DFE with a Phase Locked Loop (PLL) 9, which estimates and compensates for the phase offset in a rapid, stable manner. The use of decision feedback equalization and phase-locked loops is driven by the complexity and time variability of ocean channel impulse responses.Differential phase shift keying (DPSK) serves as an intermediate solution between incoherent and fully coherent systems in terms of bandwidth e fficiency. DPSK encodes information relative to the previous symbol rather than to an arbitrary fixed reference in the signal phase and may be referred to as a partially coherent modulation. While this strategy substantially alleviates carrier phase-tracking requirements, the penalty is an increased error probability over PSK at an equivalent data rate.Another promising solution for underwater communications is the orthogonal frequency division multiplexing (OFDM) spread spectrum technique, which is particularly efficient when noise is spread over a large portion of the available bandwidth. OFDM is frequently referred to as multicarrier modulation because it transmits signals over multiple sub-carriers simultaneously. In particular, sub-carriers that experience higher SNR, are allotted with a higher number of bits, whereas less bits are allotted to sub-carriers experiencing attenuation, according to the concept of bit loading, which requires channel estimation. Since the symbol dura tion for each individual carrier increases, OFDM systems perform robustly in severe multi-path environments, and achieve a high spectral efficiency.Many of the techniques discussed above require underwater channel estimation, which can be achieved by means of probe packets 17. An accurate estimate of the channel can be obtained with a high probing rate and/or with a large probe packet size, which however result in high overhead, and in the consequent drain of channel capacity and energy.Data link layer (MAC layer)The data link layer provides single hop data transmission capability it will not be able to transmit a packet successfully if the destination node is not directly accessible from the source node. It may include some degree of reliability. It may also provide error detection capability (e.g. CRC check). In case of a shared medium, the data link layer must include the medium access control (MAC) sub-layer.Frequency division multiple access (FDMA) is not suitable for underwate r sensor network due to the narrow bandwidth in underwater acoustic channels and the vulnerability of limited band systems to fading and multipath.Time division multiple access (TDMA) shows limited bandwidth efficiency because of the long time guards required in the underwater acoustic channel. In fact, long time guards must be designed to account for the large propagation delay and delay variance of the underwater channel in order to minimize packet collisions from adjacent time slots. Moreover, the variable delay makes it very challenging to realize a precise synchronization, with a common timing reference, which is required for TDMA.Carrier sense multiple access (CSMA) prevents collisions with the ongoing transmission at the transmitter side. To prevent collisions at the receiver side, however, it is necessary to add a guard time between transmissions dimensioned according to the maximum propagation delay in the network. This makes the protocol dramatically inefficient for underw ater acoustic sensor network.The use of contention-based techniques that rely on handshaking mechanisms such as RTS/ CTS in shared medium access is impractical in underwater, for the following reasonslarge delays in the propagation of RTS/CTS control packets lead to low throughputdue to the high propagation delay of underwater acoustic channels, when carrier sense is used, as in 802.11, it is more likely that the channel be sensed idle while a transmission is ongoing, since the signal may not have reached the receiver yetthe high variability of delay in handshaking packets makes it impractical to predict the start and finish time of the transmissions of other stations. Thus, collisions are highly likely to occur.Code division multiple access (CDMA) is quite robust to frequency selective fading caused by underwater multi-paths, since it distinguishes simultaneous signals transmitted by multiple devices by means of pseudo-noise codes that are used for spreading the user signal over th e entire available band. CDMA allows reducing the number of packet retransmissions, which results in decreased battery consumption and increased network throughput.In conclusion, although the high delay spread which characterizes the horizontal link in underwater channels makes it difficult to maintain synchronization among the stations, especially when orthogonal code techniques are used 17, CDMA is a promising multiple access technique for underwater acoustic networks. This is particularly true in shallow water, where multi-paths and Doppler- spreading plays a key role in the communication performance.Network layer (Routing)The network layer is in charge of determining the path between a source (the sensor that samples a physical phenomenon) and a destination node (usually the surface station). In general, while many impairments of the underwater acoustic channel are adequately addressed at the physical and data link layers, some other characteristics, such as the extremely long p ropagation delays, are better addressed at the network layer.Basically, there are two methods of routing. The first one is virtual circuit routing and the second one is packet-switch routing.In virtual circuit routing, the networks use virtual circuits to decide on the path at the beginning of the network operation. Virtual-circuit-switch routing protocols can be a better choice for underwater acoustic networks. The reasons areUnderwater acoustic networks are typical asymmetric instead of symmetric. However, packet switched routing protocols are proposed for symmetric network architectureVirtual-circuit-switch routing protocols work robust against link failure, which is critical in underwater environment andVirtual-circuit-switch routing protocols have less signal overhead and low latency, which are needed for underwater acoustic channel environment.However, virtual-circuit-switch routing protocols usually lack of flexibility.In packet-switch routing, every node that is part of the transmission makes its own routing decision, i.e., decides its next hop to relay the packet. Packet-switch routing can be further classified into Proactive routing, Reactive and geographical routing protocols. Most routing protocols for ground-based wireless networks are packet-switch based.Proactive routing protocols attempt to minimize the message latency by maintaining up-to-date routing information at all times from each node to any other node. It broadcasts control packets that contain routing table information. Typical protocols include Destination Sequence Distance Vector (DSDV) 28 and Temporally Ordered Routing Algorithm (TORA).However, proactive routing protocols provoke a large signaling overhead to establish routes for the first time and each time the network topology changes. It may not be a good fit in underwater environment due to the high probability of link failure and extremely limited bandwidth there.Reactive routing protocols only initiate a route discovery proces s upon request. Correspondently, each node does not need to maintain a sizable look-up table for routing. This kind of routing protocols is more suitable for dynamic environment like ad hoc wireless networks. Typical protocol examples are Ad hoc On-demand Distance Vector (AODV) 23, and Dynamic Source Routing (DSR) 27.The shortage of reactive routing protocols is its high latency to establish routing. Similar to its proactive counterpart, flooding of control packets to establish paths is needed, which brings significant signal overhead. The high latency could become much deteriorated in underwater environment because of the much slower propagation speed of acoustic signal compared with the radio wave in the air.Geographic routing (also called georouting or position-based routing) is a routing principle that relies on geographic position information. It is mainly proposed for wireless networks and based on the idea that the source sends a message to the geographic location of the dest ination instead of using the network address.Geographic routing requires that each node can determine its own location and that the source is aware of the location of the destination. With this information a message can be routed to the destination without knowledge of the network topology or a prior route discovery.Transport layerA transport layer protocol is needed in underwater sensor network not only to achieve reliable collective transport of event features, but also to perform flow control and congestion control. The primary objective is to save scarce sensor resources and increase the network efficiency. A reliable transport protocol should guarantee that the applications be able to correctly identify event features estimated by the sensor network. Congestion control is needed to prevent the network from being congested by excessive data with respect to the network capacity, while flow control is needed to avoid that network devices with limited memory are overwhelmed by data transmissions.Most existing TCP implementations are unsuited for the underwater environment, since the flow control functionality is based on a window- based mechanism that relies on an accurate esteem of the round trip time (RTT), which is twice the end-to-end delay from source to destination.Rate-based transport protocols seem also unsuited for this challenging environment. They still rely on feedback control messages sent back by the destination to dynamically adapt the transmission rate, i.e., to decrease the transmission rate when packet loss is experienced or to increase it otherwise. The high delay and delay variance can thus cause instability in the feedback control.Furthermore, due to the unreliability of the acoustic channel, it is necessary to distinguish between packet losses due to the high bit error rate of the acoustic channel, from those caused by packets being dropped from the queues of sensor nodes due to network congestion. In terrestrial, assume that congestion is the only cause for packet loss and the solution lies on decreasing the transmission rate, but in underwater sensor network if the packet loss is due to bad channel then the transmission rate should not be decreased to preserve throughput efficiency.Transport layer functionalities can be tightly integrated with data link layer functionalities in a cross-layer module. The purpose of such an integrated module is to make the information about the condition of the variable underwater channel available also at the transport layer. In fact, usually the state of the channel is known only at the physical and channel access sub-layers, while the design principle of layer separation makes this information transparent to the higher layers. This integration allows maximizing the

Function Of The Cardiovascular System

Function Of The Cardiovascular SystemIn this assessment i will be written material about that structure and function of the cardiovascular system. The cardiovascular system includes the heart, fund vessels, blood and the lymphatic system.The heart is an organ that is a none fatiguing muscle it passes amino group corrosives and opposite key nutrients. It transports other gases like atomic number 8 and hormones. It carries waste products and past they ar removed from the be, as well as that it transports de oxygenated gases and this is then expired.There are 5 functions of the heart these functions are transporting of nutrients, take overy of oxygen to working muscles, removal of waste produce, distributing key hormones and to transport De-oxygenated blood to the lungs.-Transporting of nutrientsthis is one of the important functions of the heart because it has to deliver nutrients to our working muscles. These nutrients are carried via plasma and plasma is in our blood. This i s important because the muscles need to be supplied with energy and this energy is called glucose. This is needed for sports with short explosive movements like basketball. Glucose is to a fault delivered with oxygen, and this slows that calculate of the muscle fatiguing.-Removal of waste produceThe Cardiovascular system removes waste products such as Carbon Dioxide (CO2) and Lactic Acid from the muscle create from raw stuffs. If the lactic acid doesnt get removed from your muscles then you will feel stiff and sore the next day and your muscles will not be able to per habitus as well as they did the day before.-Distributing hormonesEndocrine system is where the hormones are produced it is then transported in blood. This is made from the bone marrow witch is found in the mettle of bones. Plasma is made up of about 53-56% blood it contains proteins, carbon dioxide, ions and blood cells. This is important when it comes to sport because it prepares us for sport and adrenaline is prod uced, when adrenaline is released the athletes heart rate will increase and will get them ready for the sport. A sporting example in basketball would be at the start of an important play when the players are anxious of nervous. Transport De-oxygenated blood to the lungsthe cardiovascular system also transports de-oxygenated blood to the lung and it is then expired. The pathway of this is as followed Blood enters the heart via the superior vena cava, functions into the right ventricle passing though the tricuspid valve. As soon as the right ventricle is full this valve then snaps shut to enlistment guts flow , it is important that there is no back flow because if oxygenated and de-oxygenate blood was to mix then the working muscles would not be getting any oxygen and would fatigue. Also it would starve the brain and you would pass out. Following on with the journey, the right ventricle it then flows via the pulmonary artery (this is the only artery that carries de oxygenated blo od) the blood is then defused in the lungs and becomes oxygenated. This is a very important function as out muscles need as much oxygen as possible to function at their optical level.-BloodRed blood cells theses are also called Erythrocytes these are used to carry oxygen around the body by Haemoglobin. They also transport other nutrients round our body that it requires. They take up oxygen in the lungs or gills and release it while squeezing through the bodys capillaries. These cells cytoplasm is rich in haemoglobin, an iron-containing bimolecular that can bind oxygen and is responsible for the bloods red colour.The Cardiovascular system carries white blood cells also called leukocytes, around our body which provides immunity from invading organisms. By having white blood cells in our body this stops us becoming seriously ill from illnesses, for example leukaemia, flu or just a cutting .As our body is able to fight against it keeping the flu to a minimum.-plateletsPlatelets are sti cky fragments of cells. Like blood they are produced in the bone marrow. The function of platelets is to dominate bleeding and to form scabs. Thrombocytes do this by sticking together in cuts making tiny fibres grow. Our red cells get trapped within the individual fibres and form a blood clot. This blood clot then turns into a scab.-HeartImportant parts of the Heart which help the cardiovascular system work.the heart has a left-hand(a) hand and right side, separated by a wall of muscle called the septum.Blood from your body enters the right side of your heart through veins. The blood is dark because it has given over all its oxygen to your body.The right side of the heart pumps the blood through the pulmonary artery to your lungs to pick up oxygen.After travelling through the lungs, the blood turns bright red because it is rich in oxygen.The oxygen-rich blood then returns to the left side of your heart and is pumped out to your body through the large artery called the aorta.The cardiovascular system can be affected with intense formulation. This would have a positive affect on training. Endurance training would increase the left ventricle wall. This is called hypertrophied. Basically this means that the raise up does not have to work as hard to pump the blood around the heart because it is stronger, but it inactive pumps the right amount of oxygen and blood to the working muscles. If you were to do this training then your resting heart rate would be decreased. But over time if you was to stop training then your heart would reduce in size over time. But this could be bad if you were to do too much intense training because the heart would get to bug and your resting heart rate would be too low, if it was under 30BPM then it could be life threatening this is called hypertrophic cardiomypathy. TE-Lymphatic system diagram.svgPart of the resistive system is the lymphatic system which is made up of a network of conduits that carry a clear fluid called lymph (from Latin lympha water). It also includes the lymphoid tissue and lymphatic vessels through which the lymph travels in a one-way system in which lymph flows only toward the heart. Lymphoid tissue is found in many organs, particularly the lymph nodes, and in the lymphoid follicles associated with the digestive system such as the tonsils. The system also includes all the structures dedicated to the circulation and production of lymphocytes, which includes the spleen, thymus, bone marrow and the lymphoid tissue associated with the digestive system.http//en.wikipedia.org/wiki/Lymphatic_systemAnother function of the cardiovascular system is the regulation of body temperature, this is supportled by homeostasis.Homeostasis is the state of inner balance and stability maintained by the human body despite constant changes in the external environment. It also works by filtering the blood and removing a carefully regulated amount of water and wastes to the lungs working together with the hea rt, blood vessels, and blood to distribute oxygen throughout the body and remove wastes.It includes monitoring the water balance in the body, controlling blood sugar, body temperature control and monitoring of urea in the blood. All these processes are controlled by mechanisms such as sensors that detect the factor value. Another mechanism is the correction mechanism involving a negative feedback. Control of body temperature is controlled constriction and dilation of blood vessels, which is demonstrated in the body through vasoconstriction and vasodilation.Vasodilation involves the dilation of the blood vessels to release excess heat therefore blood will flow quickly/faster to the muscles. The vessels are widening in diameter so more blood can flow through.Vasoconstriction involves the constriction of the blood vessels to keep in any heat therefore blood will flow slowly to the muscles. The vessels are reducing in diameter so less blood can flow through.

Fighting For Our Love Ones Essay -- essays research papers

In todays world, most families have a love one struggling to live with cancer,HIV, glaucoma, or multiple sclerosis. Most of us, here in the United States, have watched a love one project the pain of chemotherapy, uncontrollable muscle spasms, or blindness. Our love ones not only suffer physical pain, but mental anguish as well. Ourdying loves ones argon at war with our Federal Government. They are fighting for a chance at a better quality of life. They are fighting for the legalization of marijuana for health check purpose. Until marijuana is legalized for medical use, our love ones are forced to break the law."my gift to my husband, John Joseph who died last form.At the end of his life, my husband was wracked with pain from lung cancer. marijuana was one medication that easedhis intense pain, and nausea during chemotherapy. But, to get marijuana to help JJ, we had to break the law.my husbands ability to tolerate chemotherapy after a coupleof puffs of marijuana extended hi s life and improvedhis quality of life (1)." That was an excerpt from a letter written by Anne Boyce to the voters of California for the passage of proposition 215. In 1996, Proposition 215 was a proposed legislation in California that makes it legal for doctors to prescribe marijuana to terminally ill patients. Proposition 215 was passed by the voters of California, but patients who use marijuana could still and are prosecuted by our Federal Government.Anne Boyce broke the law in order to obtain marijuana for her dying husband. AnneBoyce, a sixty-seven year old Registered Nurse, is not your typical criminal, now is she?          Nevertheless, if Anne Boyce was caught by the law enforcement, she would be punished to the fullest extent of the law. Federally, possession of even one joint carries a utmost penalty of one year in prison (7). Cultivation of even one plant is a felony, with a maximum sentence of five long time (7). Is this fair ? Anne Boyce and others like her are law-abiding citizens, but they or someone they love are suffering from a grave illness, and legal pharmaceuticals do not ease the pain. So, they are force to break the law. Wouldnt you do the same for your love one? I know I would. There is a bespeak for a change.          "I often drove her to the ho... ...he new millenium, the United States is well equipped with technology to address and to solve these problems.     How can we help our love ones mint candy with the pain and agony of a deadly disease? How can we improve the quality of their lives? The answer is simple. Marijuana has been proven to be therapeutic, to have countless medical benefits, and to be remarkably safe. The medical use of marijuana needs to be legalized. It would be monitored just like any other controlled substance. This solution is easy. Legalizing marijuana would go through the same procedure as the other medically prescribed substance.      It is up to us. We, the masses of America, need to follow in the footsteps of Anne Boyce as well as the voters of California. We need to write to our Congressmen. Let our Senators and our Representatives know of our wishes, our rights. We need to talk a stand. Follow the advice of a once great President, Thomas Jefferson, who once said "if people let the government decide what foods they eat and what medicines they take, their bodies will soon be as in sorry state as are the souls of those who live at a lower place tyranny."

Reducing waste in Europe Essay -- Waste Management, Waste Handling

European Union Directive 2008/98/EC outlines hierarchy of steps in which fellate handling should occur. It suggests that overplus prevention should be a top antecedency followed by re-use and recycling of materials. However in modern, demand and profit driven parliamentary procedure this tactic has very small chance of success, certainly in terms of reducing and reusing. As a result generation of municipal solid waste (MSW) is projected to rise by further 2020 by 16% in EU-27, with 80% produced in the EU-15 (which includes UK) (Skovgaard et al., 2008). This implies that The 3 Rs strategy fails to deliver its signalise objective waste reduction. Thus attention should also focus on options that could help to reduce waste accumulation rather than just prevention. One of the close successful strategies to decrease landfill waste is to divert it to Waste to null (WtE) facilities. The near popular form of energy recovery from waste, for technical and economical reason, is Waste t o Energy Incineration (WtEI). It raises a lot of controversy, mainly because it is associated with technologies from the past, when air pollution controls did not exist. This resulted in significant environmental degradation and heath issues. Understandably, this has left a bad type of incineration. Modern incinerators however emit less than 10% of pollutants than their counterparts 25 years ago (DEFRA, 2013). Technology has the potential to play a significant role as part of waste management strategy but equally primal as constituent of balanced energy mix. This essay presents available evidence which sheds in the buff light on Waste to Energy Incineration, highlighting its impact on environment, energy security and human health. In 2011 waste management contributed 17.3 MtCO2e (3.1... ...te Management 29, 17181724Shalunenko, N., I.,Korolyuk, T., A., 2012. structure glass material based on ash from waste incineration plants. deoxyephedrine and Ceramics, Vol. 69, Nos. 11 12, March, 2013Skovgaard, M., Hedal, N., Villanueva, A., Andersen, F., M., Larsen, H., 2008. Municipal waste managementand greenhouse gases. ETC/RWM working paper 2008/1 Available at http//scp.eionet.europa.eu/publications/wp2008_1/wp/wp1_2008 Accessed on 4th December 2013Tabasov, A., Kropc, J., Kermes, V., Nemet, A., Stehlk, P., 2012. Waste-to-energy technologies Impact on environment. Energy 44, 146-155UK biomass strategy, 2007. Working Paper 1 economic analysis of biomass energy. Energy Technologies unit Department of Trade and Industry. Available at http//webarchive.nationalarchives.gov.uk/+/http//www.dti.gov.uk/files/file39040.pdf Accessed on 24th November 2013 Reducing waste in Europe Essay -- Waste Management, Waste HandlingEuropean Union Directive 2008/98/EC outlines hierarchy of steps in which waste handling should occur. It suggests that waste prevention should be a top priority followed by re-use and recycling of materials. However in modern, demand and pr ofit driven society this tactic has very small chance of success, certainly in terms of reducing and reusing. As a result generation of municipal solid waste (MSW) is projected to rise by further 2020 by 16% in EU-27, with 80% produced in the EU-15 (which includes UK) (Skovgaard et al., 2008). This implies that The 3 Rs strategy fails to deliver its key objective waste reduction. Thus attention should also focus on options that could help to reduce waste accumulation rather than just prevention. One of the most successful strategies to decrease landfill waste is to divert it to Waste to Energy (WtE) facilities. The most popular form of energy recovery from waste, for technical and economical reason, is Waste to Energy Incineration (WtEI). It raises a lot of controversy, mainly because it is associated with technologies from the past, when air pollution controls did not exist. This resulted in significant environmental degradation and heath issues. Understandably, this has left a ba d image of incineration. Modern incinerators however emit less than 10% of pollutants than their counterparts 25 years ago (DEFRA, 2013). Technology has the potential to play a significant role as part of waste management strategy but equally important as constituent of balanced energy mix. This essay presents available evidence which sheds new light on Waste to Energy Incineration, highlighting its impact on environment, energy security and human health. In 2011 waste management contributed 17.3 MtCO2e (3.1... ...te Management 29, 17181724Shalunenko, N., I.,Korolyuk, T., A., 2012. Construction glass material based on ash from waste incineration plants. Glass and Ceramics, Vol. 69, Nos. 11 12, March, 2013Skovgaard, M., Hedal, N., Villanueva, A., Andersen, F., M., Larsen, H., 2008. Municipal waste managementand greenhouse gases. ETC/RWM working paper 2008/1 Available at http//scp.eionet.europa.eu/publications/wp2008_1/wp/wp1_2008 Accessed on 4th December 2013Tabasov, A., Kropc, J. , Kermes, V., Nemet, A., Stehlk, P., 2012. Waste-to-energy technologies Impact on environment. Energy 44, 146-155UK biomass strategy, 2007. Working Paper 1 economic analysis of biomass energy. Energy Technologies Unit Department of Trade and Industry. Available at http//webarchive.nationalarchives.gov.uk/+/http//www.dti.gov.uk/files/file39040.pdf Accessed on 24th November 2013

Salem Witch Trials :: essays research papers

Dearest James,It has been a long time since we have talked. I entrust you and your family are well in Jamestown, give your parents my best wishes, and tell your sister hello for me. I am writing to you in hopes that this will not be my last letter for everything has gone to pieces in Salem. It all started when trust and I decided one night to meet out in the field and hunt games in the moonlight. We meant no harm by it we only thought it might be a bit fun to do something different. We never thought anyone would fill us.Flashbackbloody shame laughed heartily. Stop it Faith, hush. You are being too noisy, some one may hear us, and then what would we do? Faith giggled as she spun around. Its gorgeous tonight, dont you agree? The moon is at its fullest, the stars are as bright as the sun itself, and we have it all to ourselves. She turned to seem for a response, but Mary just shook her head. Oh come on Mary, you k at present you want to just get up and dance. Come on now Faith too k Marys hands and pulled her up to her feet.Faith, I really dont feel like dancing. What if we were to get caught? Then what would people hazard? Theyd think we were crazy as drunkards, thats what. None of this, lets go now.Come on Just this once, and then well leave. Promise. Mary rolling her eyes but joined in as Faith began to hum and dance around. After a few minutes Faith caught a glance of some one walking down the road. She slowly stopped dancing and tapped Mary on the shoulder. Now who do you think that could be? As Mary turned to look the man began jogging towards them.Now look Faith, I told you wed get caught. Come on now, we had better explain ourselves. Mary took Faiths hand and led her out onto the road. Mr. Bradford she exclaimed. What are you doing out at this hour?His tired eye grew wide in surprise. I I he began to stutter. I have to go ladies good night, and he scurried off.Faith furrowed her brow in confusion. What do you suppose that was about?I dont know. Mary shook her head. But I dont like it, lets get out of here.Flash forwardJames, we had no brain anything would come of it.

Compaing Frankenstein by Mary Shelley and Arks and Genetic Bottlenec

Since the dawn of time, science has been in the minds of men. In the story, Frankenstein, by bloody shame Shelley, Victor pass ons with the creation of life as opposed to Arks and Genetic Bottlenecks by Harold J. Morowitz which denies the scientific validation of Noahs Ark. Science, in most cases, has interfered with human lives, especially in religion in the aspect of human cloning. In reality, it is not just a question of science, it is a matter of science versus religion. How far will science go to allow human cloning which is a test of peoples religious beliefs? Both Frankenstein and Arks and Genetic Bottlenecks provide readers with some similar and some different answers. First, Frankenstein, and Arks and Genetic Bottlenecks, deal with a similar issue that today people know as cloning. In Frankenstein film, Victor creates life out of dead bodies by reactivating the dead cells with chemicals and electricity, despite his professors warning that creation of life is only in Gods hands. In Arks and Genetic Bottlenecks, Morowitz also discusses genes and how all different organisms do not have the same compartmentalization of genes with exception of identical twins (760), and that genetic diversity is essential for the survival of all species. Though, today, cloning is a big issue which people are horror-stricken of, bloody shame Shelley, in her time, had an idea that scientists might attempt something similar to cloning which in fluided venerate in the hearts of men, and made her write Frankenstein. A similar fear is generated by Dolly, the Sheep cloned in Scotland in 1997. According to the film, Human Cloning, this has made religious activists protest against cloning in fear that science would destroy mank... ...man. The question still remains Are scientists going to learn . . . how dangerous is the acquirement of knowledge . . . (Shelley 154), or are they still obsessed with proving Harold J. Morowitz right? Works Cited Fra nkenstein by Mary Shelley. A play by Nick DiMartino, Direct. Moses Goldberg. Narr. Professor McNamar. Global Stage Production. WLIW21 Presentation. Class Movie. HSS 100-002. Fall Semester, March 22, 2002. Human Cloning Investigative Reports. Pres. Bill Kurtis. A & E Special Presentation February 4, 2002. Morowitz Harold J. Arks and Genetic Bottlenecks. Fields of Reading Motives for Writing. Sixth ed. Ed. Nancy R Comley et al. New York Bedford, 2001. Shelley, Mary. From Frankenstein. The Example of Science. Ed. Robert E. Lynch and Thomas B. Swanzey. Boston Pearson Custom Publishing, 2000. (152-156)