Harnessing the Energy of the Oceans :: Technology Engineering Papers

Jamie Lee Wise’s essay examines the varying sources of electrical energy that we can draw from the oceans. In her well-organized and researched essay, Wise carefully explains the sources and then discusses both the benefits and drawbacks of each source. In the end, Wise’s paper argues that "public awareness and education concerning the benefits of renewable energy sources need to be increased," and that the oceans can be a valuable resourece "only if we take steps to preserve this natural wonder and use it responsibly." Harnessing the Energy of the Oceans Introduction The oceans cover nearly three-quarters of our planet and contain a vast reserve of resources, yet we are only beginning to tap their full potential. The oceans can provide a wide variety of foods, desalinated water, minerals, electricity, transportation, and recreation for the people of our world; however, this discussion will be limited to sources of electrical energy that can be harnessed from the seas. The world’s energy consumption is currently doubling every 12 years and the consequences of our heavy dependence on fossil fuels are becoming increasingly apparent. Several studies have estimated that our "present reserves of oil and natural gas will be consumed within a few decades, and coal within a few centuries." In addition, "political instability in the Middle East has demonstrated the economic consequences of oil dependence" (Bregman, Knapp, and Takahashi; 1996). Environmental and political concerns are just two reasons why alternative energy sources, such as ocean energy conversion, need to be considered. Overview of Ocean Energy Conversion Technologies Technologies that currently exist for generating electrical power from the oceans can be grouped into six broad categories: thermal energy, tidal power, wave power, ocean currents, ocean winds, and chemical sources. According to Ron Bregman, an Ocean Resource Engineer, the most promising and well-developed of these technologies are thermal energy, tidal power, and wave power (1996). Thermal Energy The oceans are the world’s largest solar collectors. Each day the oceans absorb an amount of solar radiation equivalent in heat content to about 250 billion barrels of oil, according to Michael Champ in Sea Technology (1995). This solar energy that is absorbed by the oceans as heat can be converted to electricity by a process known as Ocean Thermal Energy Conversion or OTEC. This technology is based on the large temperature differential between the warm tropical surface waters and the near freezing waters of the deep ocean (Vega, 1995).

Siberin Tigers

Panthera tigris altaica, better know as the Siberian or the Amur tiger lives primarily in eastern Russia, and a few are found in northeastern China and northern North Korea. It is estimated that 150 to 200 tigers exist today in the wild. There are roughly 490 Siberian tigers that are managed in zoos world wide, and an unknown number as to how many exist privately. In this century alone, the Siberian tiger has managed to survive four wars, two revolutions, and now the brutal slaughter on their forests. Wild tigers exist in Asian countries China, Vietnam, Cambodia, Laos, Thailand, Malaysia, Indonesia, Myanmar, Bangladesh, Bhutan, India and Nepal, By this IUCN status this animal is considered to be Critical, its numbers in the wild have fluctuated from an incredibly low 24 tigers in the 1940s to what IUCN now estimates is 150 to 200 in 1994. There are only three protected areas for these tigers in Russia-the Sikhote-Alin (3,470 km2), Lazovsky (1,165 km2), and Kedrovaya Pad (178 km2) Reserves-inland from the Sea of Japan in the Russian Far East. There have been sightings of these magnificent animals in Changbaishan, near the Chinese border, were it was reported in a Chinese newspaper in 1990, and some are still found along the Russian border. The Cat Specialist Group suggests that there are probably fewer than 50 Siberian tigers in China. It is widely believed that the tigers in Russia will define the future of the species. The other sites are too small to harbor tiger populations large enough for the survival of the species. The Law of the Russian Federation on Environmental Protection and Management of 1992 gave the Siberian tiger legal protection that they deserved. Despite the law of protection, poaching has received a considerable amount of attention in the press today. Authorities say that the killing of tigers is a new enterprise. One reason for the poaching is traditional Chinese medicine. The captive program for Siberian tigers is the largest and longest managed program for any of the subspecies. The Siberian tiger is one of the models for the creation of scientifically managed programs for species in captivity. This program takes place globally in zoos and aquariums. According to the 1994 International Tiger Studbook there are about 490 Siberian tigers managed in zoos 226 of them in Europe, 151 in North America, 93 in Japan, and about 20 more scattered among Asian zoos. This captive population is descended from 83 wild-caught founders. For the most part, the Siberian tiger is considered secure in captivity. With the large genetically diverse gene pool that exists, these animals are considered to be a stable population. The Siberian tigers are the heaviest subspecies, the larger tigers weighting at 500 and more or 225-kg. With the males being heavier than the females, like many other species. The lightest subspecies is the Sumatran; these males weigh at about 250 pounds or 110 kg and the females at around 200 pounds or 90 kg. In order to obtain and maintain this weight these cats have to eat large masses of food, every day. A wild tiger can eat over 60 pounds of meat at one siting. . Despite the tiger†s great power and accurate senses, it dedicates a lot of time to hunting, because only one in ten hunting are calculated to be successful. It mainly preys on deer or wild pig, and fish providing it can catch them. Depending on the subspecies, the head-body length of these tigers is about 41/2 to 9 feet or 1.4-2.8 m. the length of the tail is 3 to 4 feet or 90-120 cm. The footpads vary in size with the age of the animal. This leads to inaccurate estimates when used it in counting the animals in wild populations. This magnificent animal carries the Chinese mark of Wang or king on the forehead. Tigers have round pupils and yellow irises, excluding the blue eyes of white tigers. The tigers have evolved to better vision at night. Due to a retinal adaptation that reflects light back to the retina. This provides to be useful when hunting at night. Tigers have excellent Binocular and color vision. At night, the tiger can see well over 6 times better than humans. The length of a Tigers tail is 3 to 4 feet long, about half as long as its body. They use their tails for balance when running through fast turns. Tigers also use their tails to communicate with other tigers. Like domestic cats, tiger claws are retractable. Like many other animals tigers mark there territory. Tigers mark their territories by spraying bushes and trees with a mixture of urine and scent gland secretions. They will also leave scratch marks on trees. The size of a tiger's territory depends on the amount of food available, and usually ranges from about 10 to 30 square miles or 26-78 sq. km. Siberian tigers sometimes have unusually large territories, this can be as large as 120 square miles. Although tigers usually live alone, their territories can overlap. A male tiger's territory usually overlaps those of several female tigers. No one knows exactly why tigers have striped, but some scientists think that the stripes act as camouflage, and aid in tiger†s hunt from their prey. The Sumatran tiger has the most stripes of all the tiger subspecies, and the Siberian tiger has the fewest stripes. Tiger stripes are much like human fingerprints; no two tigers have the same pattern of stripes. Tiger cubs are born blind and weigh only about 2 to 3 pounds or 1 kg, respective to the subspecies. They live on their mother†s milk for 6-8 weeks before the female begins taking them hunting to eat. Tigers fully developed canines in about 16 months of age, but they do not begin making their own kills until about 18 months of age. Young tigers live with their mother until they are two to three years old, then they find their own territories to occupy. The average life span of tigers in the wild is thought to be about 10 years. Tigers that are brought up in zoos can live twice as long or longer. Unlike some other large cats, adult tigers prefer to live their lives in solitude. Except for mother†s tigers who take care of their cubs. This is partly due to the fact a single tiger has a better chance sneaking up and bouncing its prey, more efficiently than a large group of tigers could. These animals and many other animals like them should be reserved. No other living creature surpasses their beauty. As this picture illustrates these animals were truly the masters of their domain. Before humans came and destroyed their homes. This cat is one of the most powerful cats in the world. Weighting in at 500 and change this animal can tear though it†s prey, like a hot knife though butter.

Students Have Your Own Swipe File!

A lot of students do not know what swipe files are, what their purpose is, and how to even make one. Well, it is really very simple; a swipe file is like a diary every writer keeps. This diary includes their previous work, and related things such as reference sites, pictures, important URL or anything that grabs your attention. You can let your imagination run wild. As a student using a swipe file will help keep you organized so you can submit your work on time and at the same time keep all the information you need in one place. Copywriters use swipe files to keep records of their work. They gather and store all needed information so that when needed all information is easily accessible. Students can do the same and benefit from the advantages offered by this simple tool. How to Make Your Swipe File Creating swipe files takes hardly a minute. There are three ways of doing this. 1. Online 2. Desktop 3. Scrapbook/Journal Making swipe files online is very easy, all you have to do is search on Google i.e. www.Tumblr.com is one of the hundreds of places where a user can create their swipe file and easily keep it updated with a click of a button. Artists would prefer a better platform for their work i.e. www.deviantart.com. You can also make a folder on your desktop. Simply create a new folder and you can save anything that appeals to you directly into it. Another option is to drag your important files or documents into the folder as easy as that. If you decide to make a scrapbook or journal, you can use any empty book and fill it with loads of stuff. You can add clips from newspaper or printouts or you can cut and paste pictures, make it as creative and original as you want to. Benefits There are many benefits in containing a swipe file. 1. All work you save will be in one place. 2. You can retrieve any work anytime. 3. If you save your work online it will not be erased and will be stored as long as you wish. 4. You can share your work online with your friends and with the world. 5. Organized files help save time. 6. You can make and save copies of your work. Disadvantages 1. Saving work may not always be easy as lots of times servers are full or the Internet is low. 2. Files from desktops can be erased. 3. Your scrapbook or journal can be misplaced. Conclusion Students will benefit from making their own swipe files. As mentioned above, it will help save time and efforts. Having all your information organized in one place is very useful in a student’s life as a lot of times they have to meet deadlines. This also becomes a healthy habit. Swipe files are the most efficient way of keeping your work safe and secured and they are easy to access anytime you want to. In short, students should maintain swipe files to gain easy access to their work.