Background of steganography

Background of steganographySteganography has been settled from Greek word Stego which means silver screen and Graphia which means writing. Steganography is an ancient technique of covert converse. The earliest salmagundi of Steganography has been reported by the Chinese. The inscrutable cognitive content was written in genuinely fine silk or constitution, and hence it was rolled into a b alone and cover with wax. The messenger would either swallow the ball or hide it in his nether parts. Herodotus has menti hotshotd in one of his seminal works of history, Histories during the 400B.C about the customs of privy writing. In his writings he has mentioned about the conflicts mingled with Greece and Persia. A king named Histiaeus encouraged the Aristagoras of Miletus to revolt against the Persian king. He apply to tonsure the head of his most trusted handmaidens and tattooed the scalps with cloak-and-dagger kernel and waited for the hair to grow. The servant employ to tra vel between the b posts without involveing allthing contentious freely. At the reception abolish his head would be tonsured again and the message will be conv shopping centerd. Similarly during the World War II, the Germans invented the use of microdots. Image restricting great exposit were scaled down to the size of microdots. The German usage of secret sharing is regarded as the recent evolution of Steganography. A nonher type of Steganography is during the Vietman War were the captured US armed force showed hand gestures during a photo sessions to convey some(prenominal) military secrets. The field of Steganography is limitless and what ever so kind of cover media advise be used for trickleing secret messages. Cover medias loafer be text, characterizations (grey, binary, color), audio, film etc. An example is illustrated as follows.Siva and Adam dined happily.The following message is not simply a plain text but it carries a secret message within it. By extracting ev ery second garner from each word we derive a secret message as follows.IndiaOther methods of non technical Steganography is employ lime and new(prenominal) citrus liquids to hold open secret information. The message will be imperceptible to the eye. When it is shown over a flame the writings will become perceptible. Steganography is method of information hiding. Steganography washbasin be considered as an art as well as perception for secret communication.The best way to explain the adjudicate of using Steganography is the prisoner Problem. today let us consider cardinal prisoners Alice and Bob, and Wendy to be the warden. Now if Alice and Bob want to devise a plan for escaping accordingly they got to drop dead with each other. If Wendy is a passive warden because he wont substitute in there communication but if he is an active warden then he will interfere and extract the secret message sent. therefrom Alice and Bob got to communicate in much(prenominal) a way that Wendy is not able to decipher there plan. This can be through by the technique of Steganography.Steganography is been used in golf-club to enable secret communication. It is too being used by terrorist for covert communication which is potential for endangering our field as well as world trade nurseion. Despite the ill movement there atomic number 18 positive sides of Steganography. For example a photographer can store the aperture size, future references etc while taking a picture. Steganography has a tolerant application in medical imaging were the details of the patients argon engraft within the medical moving picture. Similarly Steganography can be used for dissimilar friendly applications. It is also used for copy right protection using it along with Watermarking.The use of Steganography also has an important role in beef up national security. Steganography is defined as secret hiding. It can also be regarded as secret sharing since messages can be sh bed secretly without being hacked or corrupted.COMPARISON BETWEEN CRYPTOGRAPHY, STEGANOGRAPHY AND WATERMARKINGThe other forms of info hiding be cryptography and watermarking. cryptanalytics is a technique in which the secret message is encrypted and sent in an unin keyigent format. The basic dissimilarity between Steganography and cryptography is that Cryptography scrambles the data whereas Steganography just hides the data. Cryptography scrambles the secret data in such a way that it outs to be gibberish to any unintend drug exploiter. The secret data to be communicated is a mixture of replenishment and substitution and hence any unintended user shift come across the message.Steganography is different from Cryptography. Steganography rather hides the data whereas Cryptography encrypts the data. Steganography provides much more security when compared to cryptography because there is no chance of any unintended user to populate that a message is being sent whereas in Cryptography ther e will always be a suspicion that a message is being sent. therefore these are more prone to be hacked or suppressed.Watermarking is generally used for authentication and copyrights protection. Watermarking can be used for creating a reach in order that it is recognizable. It can also be used to mark a digital file so that it is intended to be visible (visible watermarking) or visible to its creator (invisible marking). The main purpose of watermarking is to pr regulart the illegal copying or claim of ownership of digital media.CHARACTERISTICS OF STEGANOGRAPHY, CRYPTOGRAPHY AND WATERMARKINGThe common characteristic between Steganography, Cryptography and Watermarking is that they transmit the secret information in such a way that only the receiver is able to decrypt the data. These techniques had been prevalent during the ancient times have been transported to the digital world. It has become nearly unfeasible to extract or detect the secret messages. In digital domain Steganogr aphy and watermarking have a tie and it is majorly used in digital images. These have other uses as well. Both cannot populate by themselves and hence they require cover objects. Steganography requires a cover media to carry the secret information and watermarking requires a carrier object which it is intended to protect. These similarities reach a link within them and hence some modifications can pass the transportation from one technique to another. Due the similarities range between these it is fractious to tag between the both but actually there is a remarkable difference between them. Cryptography encrypts data in two methods secure or unbreakable (e.g. One-time pad) strategys and breakable (e.g. RSA) systems. Through both the systems communication carried out is known to all. But it is time consuming and often unreal to crack a order. The robustness of the code lies upon the difficulties faced while reversing the code in different permutations and combinations. Due t o its robustness it is used for security purposes. For example Cryptography is used for online shopping, banking etc. The credit card number, expiration etc and other crucial informations are encrypted and sent so that an unintended user cant access the details.Steganography offers high carrier capacity keeping engraft message invisible and maintaining the fidelity of the cover media. The efficiency of the Steganographic method is that one shouldnt know that a media file has been altered in order for embedding. If the malicious user knows if there is some alteration the Steganographic method is defeated and less efficient. The engraft message is very fragile and hence if any modification is done to the stego image the whole secret message is corrupted. The effectiveness lies on the cogency to fool an unintended user. The layers of communication can be more than one layer. A secret message can be engraft with a digital image which in turn can be embed within another digital medi a or scene clippings.Watermarking is requisite in order for authentication and copyright protection of digital files. The embed watermarking is required in an object to make it impossible to remove completely. If the plant watermarking is removed, then the marked object is either distorted or destroyed do it useless for anyone. This is the reason why watermarking is more robust when compared to the other image processing techniques, such as compression, cropping, rotation etc. hence even if a fiddling bit of information is extracted by modification and temper the rightful owner can still claim ownership. If the owners name is embedded in the digital image and the particular image then the superior information is tampered and destroyed. Unlike Steganography, it is acceptable for everyone one to see the watermark embedded in it including the invisible ones.COMBINED EFFORTS OF STEGANOGRAPHY, CRYPTOGRAPHY AND WATERMARKINGCryptography is used as a paisano of the other two data hid ing techniques. Data is encrypted in both the techniques in order to increase the randomness of the Steganography to avoid the statistics-based attacks and to protect the hidden data in watermarking. Commonly it is a practice to first encrypt the data and then use any one of the embedded techniques.The importance of watermarking can be stated as follows. Suppose Rs hundred pen nib is introduced in December 2009 then watermarking is required in order to prevent illegal copies. If the bill is shown in light a clarified image will appear within the large image. The watermarking is actually a part of the large paper and is visible on both sides. so it becomes difficult to produce a paper with such features. In increment to these features some tiny writings which are invisible to the human eye are present in the paper.A banker having the necessary equipments (magnifying glass) can tell the difference between the original bill and the fake bill. Steganography makes its play here. Th e tiny printing done on the bill represents Steganography. It is implemented in order to achieve high security. The tiny printing done in the paper cannot be copied since any commercial printer is incapable to print such a fine and thin print leading to black spots. These are the reasons why Steganography is used for high security.Cryptography is actually implemented in the bill. A serial number is been printed in the bill which may contain information about the location and date of bill is printed or any other confidential information. The unique serial number for each bill can be used for tracking purposes. Using Steganography, Cryptography and Watermarking it becomes impossible to reproduce Rs100 bill. It must be kept in mind that all three are different and have different functionality.REQUIREMENTS OF STEGANOGRAPHYcAny digital media can be used as a cover media. The cover media can be a text, image (color, gray), audio or video etc. Cover media is required in order to hide and c arry the information. Usually digital images are required in order to hide secret messages. The secret message is hidden within the digital image. after(prenominal)ward the message is embedded within the cover mediaAn innocuous image consisting of scenery, stack and other objects are the nominees for cover media. The availability of natural images is not a problem due to the affordable price of digital cameras nowadays. Natural images are the best candidates for cover image since they have higher resolution providing flexibleness and other necessary need.Images are selected because the cover media is selected depending upon how the human visual system works. The gray image consists of pixels with intensity time value from 0 to 255. The human eye cannot differentiate between a pixel intensity of 244 and 245. It will appear both the pixel intensities to be same. Also natural image s contains lots of noise and hence there is lots of pixel value intensity difference especially in the edges. This variation in the pixel intensity is known as randomness and can be utilize to embed the data without providing any suspicion to human eye. The human visual system wont be able to distinguish between the image before modulation and the image after modulation. The secret data is embedded within the cover image. The resulting image is called a stego-image. The stego-image will appear to be the same as the original image. The human eye cannot usually distinguish between the stego-image and the original image except there is a probative change between the images. In that case the Steganographic method employed is ineffective. Hence there are certain Stego-system criteria which we have to follow while doing a Stegagraphic implementation. They are stated as follows.The major criteria of Steganography that the cover media shouldnt be importantly altered or modified.The embedded data should be directly encoded in the cover and not in the header or wrapper.The embedded data should be immune to modifications of the cover. That is if the cover media under goes any change then data embedded within it should be unaltered.During transmission there are chances of noise to occur and hence distortion due to noise cannot be eliminated. Due to this issue error coding algorithms should be included where ever it is required.It is advisable to avoid the suspicious portions while embedding the message in the cover. This because after embedding in these regions they become open to suspicion. For example by embedding in smooth portions of the image, the resultant image becomes distorted and open to suspicion. Hence such portions are often avoided and portions where there is variation in the pixel intensity are preferred.The embedding efficiency must be improved. Efficiency of the embedding capacity depends upon the number of pixels in the image used for embedding purposes.The stego-image should be robust to steganalysis. Steganalysis is a method of identifying the di fference between the original image and stego-image. Using steganalysis one can derive the information about the secret message.The stego-image should reassemble the original image and there should be any suspicion.The cover image should have high carrier capacity. That is the embedding capacity should be large. The amount of information present in the image should be resistant to distortion and should be comparable to the number of pixels present in the image.The three basic requirements of Steganography are robustness, capacity and imperceptibility. All these requirements should be satisfied for having an effective Steganographic method.

Good and Evil Angel

approximate and lousiness backerThe play begins with the Chorus informing the audience active the main image, Faustus, a scholar, like Icarus, whose waxen wings did mount preceding(prenominal) his reach (Prologue, 21). In the very first scene of the play, Faustus talks about(predicate) philosophy, medicine, law, and theology and is hesitant about all in all. Lastly he chooses to study whoremaster. He rejects theology. He is glutted more with conceit (Scene I, 18) and he prefers black magic to what he preferred before he asserts . . . Divinity, adieu (Scene I, 48), that is, he rejects to be in heaven and reunite with God.The right(a) and the Evil Angel that turn out in s incessantlyal p contrivances of the play are both documentary and symbolic they represent Faustus inner conflict. They appear in the most melodramatic scenes w present Faustus is in conflict. They appear offering advice as Faustus is preparing to sign in rake a beget so as to give his soul to match. T hey in addition appear at the time Faustus is talking to Mephistopheles about rueing. Here, while Good Angel urges Faustus to repent and wish Gods mercy, Evil Angel tells him not to repent. ultimately he agrees with Evil Angel.GOOD ANGEL. O Faustus, lay that damned prevail aside,And gaze not on it, lest it tempt thy soul,And heap Gods heavy ira upon thy headRead, read the Scriptures that is blasphemy.EVIL ANGEL. Go forward, Faustus, in that famous art,Wherein all personalitys treasury is containedBe yard on earth as Jove is in the sky,Lord and commander of these elements.Exeunt (Scene I, 70-77)GOOD ANGEL. Sweet Faustus, leave that execrable art.FAUSTUS. Contrition, prayer, remorse what of them?GOOD ANGEL. O they are means to bring thee unto heaven.EVIL ANGEL. or else illusions, fruits of lunacy,That makes men foolish that do trust them most.(Scene V, 15-19)The angels do appear at the same time in the play and they leave together as well. Interestingly enough, it is always t he Good Angel that appears first and it is Evil Angel that speaks the last words. If we think of the angels symbolically, the Good Angels appearing first probably refers to Faustus sense of right and wrong and Evil Angels last words may symbolize Faustus self-temptation.Valdes and Cornelius magicians will initiate Faustus black arts. As Faustus is about to sign in blood a contract so as to give his soul to Lucifer, the Good and Evil Angels enter again. As Faustus signs the contract he asks about hell, however persuade himself that hells a fable (Scene V, 126) despite Mephistopheles honest responseFAUSTUS. Was not that Lucifer an angel once?MEPHIST. Yes Faustus, and most dearly loved of God.FAUSTUS. How comes it then that he is prince of d condemnables?MEPHIST. O, by aspiring pride and insolence,For which God threw him from the face of heaven.FAUSTUS. And what are you that continue with Lucifer?MEPHIST. Unhappy spirits that fell with Lucifer,Conspired against our God with Lucif er,And are for ever damned with Lucifer.FAUSTUS. Where are you damned?MEPHIST. In hell.FAUSTUS. How comes it then that thou art out of hell?MEPHIST. Why this is hell, nor am I out of it.Thinkst thou that I, who saw the face of God,And tasted the eternal joys of heaven,Am not tormented with decennium thousand hellsIn being deprived of everlasting blissO Faustus, leave these frivolous demands,Which strike a terror to my fainting soul.(Scene IV, 64-82)There is the doubtfulness of choice in the play. Faustus has chosen to sign the contract. He is completely withdraw in his choice since Mephistopheles is quite honest in his attitude. Faustus fault here is to ignore repentance as an alternative. He also misunderstands the concept of hell, opinion that it is just physical torment. Faustus is unaware about the fact that hell is a kind of psychological torment which is in fact a go of his tragedy.In the fifth scene, Faustus asks Mephistopheles who made the world (Scene V, 237). Mephisto pheles avoids answering Faustus question and introduces seven-spot deadly sins Pride, Covetousness, Envy, Wrath, Gluttony, Sloth, and Lechery (Scene V, 276).In changing the spectacle to the Seven pestiferous Sins, Marlowe has not only(prenominal) opened the way for some moral satire, exclusively he has on purpose and ironically presented the pageant as the visible gratification of Faustus. Faustus himself responds with the greatest delight, blasphemously comparing his joy in the procession with Adams joy at the commode of Paradise on the day of his creation. Delight in the Seven Deadly Sins is a far cry from the answer to who made the world, and it is not without foreland that, after this episode, Faustus makes no more speculative inquiries of any kind. (Cole 1962, 214)As Fermor asserts, the character of Faustus is not that of one man, but of man himself, of Everyman (Fermor 84). In Everyman the tragic injury pride, wilfulness causes blindness to the nature and destiny of man . . . hubris destroys the understanding of the nature and limitations of knowledge (Cole 1962, 234). Faustus actions are completely humane. As Cole has suggested, Faustus never causes anyones remainder (Cole 1995, 124) he causes his induce damnation.Dr. Faustus suggests that because human beings are creatures in whom good and evil are tragically intermingled, the process of purification which the magicians described is impossible. The human intention to attain a godlike status and to exert benevolent instruction over history is almost inevitably corrupted by self-centered desires for wealth, sensual indulgence, and political force. The refusal to admit this is Faustus fatal error, as is perfectly agnize when he reads from Jeromes Bible If we say that we haue no sinne, / We deceiue our selues (69-70). (Mebane 135)The theme of appearance versus world is an important one throughout the play. Faustus confuses appearance and reality and wants to go beyond what he sees.By Ari stotelean definition, a tragedy is about a hero whose fatal flaw ends himself. Doctor Faustus is a typical Aristotelian tragedy where a man of high importance a scholar out of pride, sells his soul to Devil. The tragic downfall of the hero is when he signs the contract with the devil. There is also catharsis in the Aristotelian sense the audiences spirit pity and fear pity for Faustus suffering his tragedy, then fear of themselves putting themselves in Faustus place. Faustus can repent before the end of the play but he prefers not to he misleads himselfFAUSTUS My hearts so hardned I cannot repentScarce can I name salvation, faith, or heaven,But dreadful echoes thunders in mine ears,Faustus, thou are damned (Scene V, 192-95)And long ere this I should have slain my self,Had not sweet pleasure conquered deep desperation. crap not I made blind Homer sing to meOf black lovage love, and Oenons death? (Scene V, 195-98).Why should I die then, or basely despair?I am resolved Faustus sh all neer repent. (Scene V, 205- 206)Doctor Faustus represents the attitudes of Renaissance England, it symbolizes the Renaissance psyche who wants to go beyond his perception. Marlowe reflects the Renaissance perception of reason that gives human beings the power to discern, as well as the power to choose and finally forms the root for moral responsibility (Cole 1995, 127). Thus Faustus himself is responsible for his own actions it is Faustus who causes his own fall. He suffers from personal responsibility of free human choice and the inevitable consequences of his own choice.Primary Source(s)Marlowe, Christopher. Doctor Faustus Norton Anthology of English Literature sixth edition vol. 1. Ed. Abrams, M.H. newly York M.H. Norton Company 1993.Secondary SourcesCole, Douglas. Christopher Marlowe and the Renaissance of Tragedy. Westport, CT. 1995._. Suffering and Evil in the Plays of Christopher Marlowe. Princeton, NJ. Princeton University foment 1962.Fermor, U.M. Ellis. Christopher Marlowe. London, Methuen 1927.Mebane, John S. Renaissance Magic and the Return of the Golden Age The mystic Tradition and Marlowe, Jonson, and Shakespeare. Lincoln, NE., University of Nebraska Press 1989.

Free Richard III Essays: The Seduction of Lady Anne :: Richard II Richard III Essays

Richard III and The Seduction of Lady Anne   Richard, Duke of Gloucester, is a vast seducer.  However, it is easier when the seducee is rather frail in mind and heart, as I bank was the case with Lady Anne.  Perhaps Lady Annes ego was as much engaged as her anger was initially.  Gloucester chips away at her resolve masterfully, but lets look at the facts.  She knows that Gloucester despatched her husband and her father-in-law.  This fact is undisputed (within the play).  Gloucester admits both murders to her saying, your spectator was the cause of that effect the murders (I.ii.121).  Her father-in-laws corpse is lying just feet away.  Yet in under two hundred lines, Anne goes from calling him a black sensation and foul devil to accepting his ring (I.ii.34 I.ii.50).               This is quite a turnaround.  She could make water walked away but she was more intrigued or flattered than angered or humiliated.  Richard uses panegyric to woo her.  He repeatedly tells her that he killed her husband and father-in-law to be qualified to spend one hour in her sweet bosom (I.ii.124).  Gloucester goes on to tell her that He lives, that loves thee better than he Edward could (I.ii.141), meaning that Gloucester loves her better than her husband did.  After she spits on him, he calls it (the spit), poison from so sweet a place (I.ii.146).  Gloucester is unrelenting in his flatteries and she does not walk away.                The most noteworthy portion of this scene is when Gloucester bares his chest and hands his steel over to Anne to kill him and asks her to end his pain if she wont have him.  She starts for him with the mark, but drops it when he tells her that twas thy heavenly memorial tablet that set me on to kill her husband (I.ii.182).  He then offers to turn the sword on himself.& nbsp Within a few seconds, she goes from raising his own sword to him, to weakly replying, I would I knew thy heart (I.ii.192).  She still questions his motives, but Gloucester has understandably already won her and slips a ring on her finger.               It is little curiosity that Gloucester brags to himself of this conquest.  Her father-in-laws corpse is barely cold and she has accepted Gloucester as her next husband.

The Abortion Debate in the 2004 Presidential Election :: Politics Political Essays

The miscarriage Debate in the 2004 death chairial ElectionAbortion is a major issue that affects individual lives daily. It has become a baffling f kneador in determining the solution in having the free preference for a woman to abort their unborn baby. Even though it was not fully recognized in the presidential election, there was discussion as to whether or not it is morally in good order to perform this example. President render believes that aborting an unborn baby is morally wrong because he believes in defend the rights of the unborn and believes that partial birth abortion is a vicious act that discriminates against small fryren who are inches away from life. On the opposing side is Senator Kerry, who believes that aborting an unborn child should be permitted because he believes in protecting womens choices and enforcing womens silence rights. President Bush believes banning abortion except for the cases in rape, incest, or to save the mothers life. He believes in the rights of the unborn and born baby. In 2003, President Bush signed the Partial Birth Abortion Ban action of 2003, which prohibits the practice that performs the overt act, other than comp allowion of delivery that kills the partially delivered keep fetus. (http//www.theorator.com/bills108/hr1545.html). By President Bush signing this act he explained that there would be the termination of this terrible act in killing loose lives that are about to come in the world. The bill I am about to sign protecting innocent new life from this practice reflects the compassion and humanity of America. (http//www.whitehouse.gov/news/releases/2003/11/20031105-1.html). His main goal is to descend the numbers of abortions in America. (http//www.issues2000.org/George_W__Bush_Abortion.htm). Senator Kerry believes that it is not the issue of pro-abortion but the issue of pro-choice. He believes that every woman should have the right of choice, which is taken away from her resulting in banning aborti on. My personal belief about what happens in the fertilization surgery is a human being is first formed and created, and thats when life begins (http//www.sonrisecma.com/blogs/sonrise3/ enumeration/2004/07/22/611.aspx). He believes that the political relation should not have a right to intervene in somebody else judgment and quotes on Bill Clinton narration that Abortion should be rare, but it should be safe and legal and the government should stay out of the bedroom.(http//www.npr.org/politics/issues2004/) He believes that enforcing womens privacy rights would let the mother decide to abort her unborn baby or not. plentiful is pro-abortion and Conservation is anti-abortion. In both opposing sides, there are alternatives that relates to abortion.

Industrial Revolution as a Time of Change Essay -- Industrial Revoluti

Industrial Revolution as a fourth dimension of Change The Industrial Revolution was a beat of drastic shift that transformed hand tools and hand made items to machine manufactured and produced goods. Inventions brought on the most drastic changes during the Industrial Revolution. Machines made life much easier patch decreasing prices of goods and generally improving life. (mhirotsu.htm). Before the 1750s, life was primitive solely simple, which is vastly different from the complex culture that arose from the Industrial Revolution. Before the frontmost Industrial Revolution, Englands economy was based upon its cottage industry. The workers would purchase raw materials from merchants, receive them back to their cottages, and at home is where the goods were produced. This was usually owned and managed by unitary or few people. This industry was efficient, yet due to the fact that productivity was low, it make the prices high. The longer the it took to create the prod uct, the higher the cost. Goods were expensive, and in turn however wealthy people could afford them. (mhirotsu.htm). The Industrial Revolution was based mainly upon the Cotton Industry , for most of the inventions created during that period were mainly for making and producing cotton. In the year 1773, there was a high demand for cotton cloth, but the production was low (mhirtostu.htm). This problem needed to be solved. The solution came from earth-closet Kay, a British weaver, who invented and fashioned the flying shuttle, which cut weaving time in half. John Kay was also a pioneer, and his hot invention coat the way for many more inventors. At first, workers did not accept the machines, and in numerous cases many inventions were destroyed, but the inevitable was unst... ... brought on many new adjustments in peoples lives. The grinder system was a reliable way to swallow prices on goods, but the quality of the workers lives declined. Women and children were re quired to work long, hard hours, and as a result, many people became sick and developed diseases. With time, the workers became aware of their strength rights, many got together to form Labor Unions. Different groups gave rights to workers and gave them the power to strike. As more and more laws were enforced regarding the working schedule, working conditions improved and the factory system began to blossom (change.html). Throughout the Industrial Revolution, many new inventions and machines were created and many advances were made. The revolution was a massive turning point in history, and from and then on, tremendous progress evolved creating the society we live in today.

Ballard Fuel Cell :: essays research papers

THE BALLARD FUEL CELLThe Ballard displace carrell is a power generating device which combines hydrogen (which can be obtained from methanol, natural gas, petroleum) and group O without the habituate of combustion in order to generate electricity. Since fuel cells operate very(prenominal) quietly and efficiently and their only emissions are pure water and mania they are expected to be the future of power generating machines.The PEM fuel cell is made of two plates with a plastic membrane coated with a catalyst in the middle. Hydrogen is then fed through the bring on iodine side of the plates and oxygen is fed through the new(prenominal) side. The hydrogen and oxygen atoms are drawn toward each other. Only one part of the hydrogen atom the proton can pass through the membrane. The negatron has to take the farseeing way around through an external circuit. This creates electricity. The oxygen side attracts protons and electrons that have traveled through the external circui t. This is where the byproducts water and awake are formed. Each fuel cell operates continuously as long as hydrogen is supplied. Single cells are combined to produce the mandatory amount of power.PEM fuel cells operate at around 90 degrees Celsius and demo off-key 90 degrees Celsius of heat, which is a fairly low temperature. This is much give away than high temperature combustion engines, which operate at about 2500 degrees Celsius and give off 125 degrees Celsius of heat. This means the Ballard fuel cell can react promptly to load changes and makes it ideal for motor vehicles. Which is why Honda, Nissan, Volkswagen Yamaha, Daimler Chrysler and Ford have tap the use of these cells.The cities of Vancouver and Chicago are currently testing Ballards fuel cell transit buses. They are seeing the maintenance requirements of the pollution escaped buses as well as the public reaction to the program.

The Sierra Club as an Interest Group Essays -- Environment Nature Essa

The Sierra Club as an arouse GroupThe Sierra Club is a national organization sanctified to the preservation of the environment. Founded in 1892 in California by conservationist rear end Muir, the Club is made up of 750,000 people devoted to the exploration, enjoyment, and the protection of the natural environmental. Headquartered in San Francisco, it has numerous state and regional chapters taking part in the fight for protection. According to Janda, an important part of pluralism was that new divert groups progress to as a matter of course when the need arises (Janda 176). Such is the shift with the Sierra Club. With the establishment of Yosemite National Park by the US coitus in 1890, the Club formed two years later in 1892 to lead a campaign to defeat a proposed reduction in the boundaries of the Park. Moreover, the Sierra Club formed when there was a need and boost interest in environmental preservation. Another important aspect of interest group formation is leading. Founding the Sierra Club, John Muir was an explorer, naturalist and writer devoted to the environment. Campaigning for the conservation of land, water and forests in the United States, he helped influence congress to pass the Yosemite National Park Bill and persuaded chairman Teddy Roosevelt to protect 150 million acres of forest reserves. His allegiance and effort helped many people begin to understand the importance of conservation. non just confined to information in books, his commitment allowed people to feature nature for themselves. Who is being organized is also an important factor. Regarding the Sierra Club, a range of people were organized. Whether rich, educated, businessmen, farmers, or women, environmental protection is important to... ...rent perspectives, environmental protection will be a topic of debate and controversy. In conclusion, the Sierra Club is a national interest group. Because of a disturbance, leadership and numerous like-minded individuals, the Sie rra Club succeederfully organized in 1892. Taking on roles of representation, participation, education, agenda building and program monitoring, the it owes much of its success to its resources of members, money and lobbyists. As a group, the Club has accomplished much through with(predicate) direct lobbying, grassroots initiatives, high-tech lobbying and coalition building. With the environment being such(prenominal) a debated topic, the Sierra Club is an organization devoted to its preservation. Works Cited Janda, Kenneth, Jeffrey M. berry and Jerry Goldman. The Challenge of Democracy. Boston Houghton Mifflin, 2004. The Sierra Club. www.sierraclub.org