2008年11月2日星期日
Reading mind
It is the first time for me to come across the concept of mind reading. However, after reading the two articles, I become familiar with this kind of technology. Just like many other new technologies. Mind reading has both benefits and shortages. A question comes out from the articles that how should human beings predict and minimize potential unethical abuses of this new technology. There are so many ethic problems and as a researcher we must make sure that our researches are not wrongly used by people. We can ask the government to make some criteria about who can have brain mapping and who cannot; use laws to protect people’s privacy. Most importantly, discourage parents having their children being tested. This technology is just like the weapons. It can benefit human being to some degree, but it should be used under the government’s controlling. Not all of us can have this technology and not all of us can use it. Using of this technology should be in some important period and environment. Countries and government should set laws on abuse of mind reading technology. The abusing of this should be punished by government. People themselves should also realise the importance of this, they should educate their next generations and supervise each other. Human beings should realise that even though we can benefit from this new technology in some aspects, the bad situations that will return to us are more serious. If most of the people can realise this and government can give some stress on this, the abuse of the technology will not become a big problem in the future.
Difficulties of writing in my engineering classes
As English is not my mother tongue, writing essays in English is really a difficult thing for me. After writing so many essays, such as the academic writing in eg1471 classes, the lab reports of engineering classes and so on, I have mainly came across these problems. The first and most important one is the new words. As a Chinese student, I have met lots of news words in my engineering classes, it is impossible for me to remember all of them. But when I am writing, I must use them correctly and frequently. Thus, in order to solve this problem, I must find a new way to remember the new words and try to remember as more as possible. Second difficult is the grammar. As we really do not have too much chance to speak English, the grammar is a big problem for us. I always think things in a way called traditional Chinese way. However, as English grammar points have much different with Chinese grammar, it is really hard for Chinese students to beautify their sentence structures and other grammar points. If we want to enhance our writing ability, we should read more English essays and write more. It will take a long time to make us familiar with the English writing skills. However, I believe that after a long time of training, remembering new words and learning, I will be familiar and more skillful in English writing.
Challenges for virtual reality
Basically, virtual reality is simply an illusory environment, engineered to give users the impression of being somewhere other than where they are. As you sit safely in your home, virtual reality can transport you to a football game, a rock concert, a submarine exploring the depths of the ocean, or a space station orbiting Jupiter. It allows the user to ride a camel around the Great Pyramids, fly jets, or perform brain surgery. Virtual reality offers a large array of potential uses. Already it has been enlisted to treat people suffering from certain phobias. Exposing people who are afraid of heights to virtual cliff edges has been shown to reduce that fear, in a manner much safer than walking along real cliffs. Similar success has been achieved treating fear of spiders. Other experiments have tested virtual reality's use in treating social anxieties, and show that it can be a successful treatment for some more serious disorders, such as post-traumatic stress disorder. Virtual reality also offers advantages for various sorts of research, education, and training. However, for virtual reality systems to fully simulate reality effectively, several engineering hurdles must be overcome. The resolution of the video display must be high enough. The field of view must be wide enough and the lighting and shadows must be realistic enough to maintain the illusion of a real scene. And for serious simulations, reproducing sensations of sound, touch, and motion are especially critical. It may not be virtual reality per se, but a related concept also seems to be growing in cyberspace, as the World Wide Web has become host to whole worlds populated by virtual people guided by their real-world owners. What’s more, such worlds could be in the process of merging with the real world, as computer records of the physical environment (as available via Google Earth or Microsoft’s Virtual Earth) could be interlaced with the sites like Second Life. It would then be possible to virtually visit real locations, explore a city’s restaurants and hotels, and engage in other virtual tourist activities.
From:http://www.engineeringchallenges.org/cms/8996/9140.aspx
The original:
To most people, virtual reality consists mainly of clever illusions for enhancing computer video games or thickening the plot of science fiction films. Depictions of virtual reality in Hollywood movies range from the crude video-viewing contraption of 1983’s "Brainstorm" to the entire virtual universe known as "The Matrix."
But within many specialized fields, from psychiatry to education, virtual reality is becoming a powerful new tool for training practitioners and treating patients, in addition to its growing use in various forms of entertainment. Virtual reality is already being used in industrial design, for example. Engineers are creating entire cars and airplanes "virtually" in order to test design principles, ergonomics, safety schemes, access for maintenance, and more.
Basically, virtual reality is simply an illusory environment, engineered to give users the impression of being somewhere other than where they are. As you sit safely in your home, virtual reality can transport you to a football game, a rock concert, a submarine exploring the depths of the ocean, or a space station orbiting Jupiter. It allows the user to ride a camel around the Great Pyramids, fly jets, or perform brain surgery.
True virtual reality does more than merely depict scenes of such activities — it creates an illusion of actually being there. Piloting a Boeing 777 with a laptop flight simulator, after all, does not really convey a sense of zooming across the continent 5 miles above the surface of a planet. Virtual reality, though, attempts to re-create the actual experience, combining vision, sound, touch, and feelings of motion engineered to give the brain a realistic set of sensations.
And it works. Studies show that people immersed in a virtual reality scene at the edge of a cliff, for instance, respond realistically — the heart rate rises and the brain resists commands to step over the edge. There are significant social applications as well. It has been shown that people also respond realistically in interactions with life-sized virtual characters, for example exhibiting anxiety when asked to cause pain to a virtual character, even though the user knows it's not a real person and such anxiety makes no rational sense. It is clearly possible to trick the brain into reacting as though an illusory environment were real.
What are the practical applications of virtual reality?
Virtual reality offers a large array of potential uses. Already it has been enlisted to treat people suffering from certain phobias. Exposing people who are afraid of heights to virtual cliff edges has been shown to reduce that fear, in a manner much safer than walking along real cliffs. Similar success has been achieved treating fear of spiders.
Other experiments have tested virtual reality's use in treating social anxieties, such as fear of public speaking, and show that it can be a successful treatment for some more serious disorders, such as post-traumatic stress disorder. Virtual reality also offers advantages for various sorts of research, education, and training. Some neuroscientists believe that virtual reality experiments can provide insight into the nature of awareness and consciousness itself. Surgeons can practice virtual operations before cutting into real people; soldiers can learn combat tactics in virtual worlds without shooting real bullets.
Virtual reality could also be used in business, advancing video conferencing to a level in which people located in widely dispersed parts of the world can interact in a shared environment and carry out tasks together. Meeting the engineering challenge of allowing dispersed people to seamlessly see, hear, and touch each other, as well as share real objects and equipment, would be particularly useful for the military and emergency response teams, too.
All of these scenarios involve outfitting the user with a virtual reality interface — often a display screen mounted on the head so as to cover the eyes and ears — that communicates with a computer. The computer stores all the necessary information to generate the virtual scenes and sounds. Typically, the visual and auditory information is transmitted separately to each eye and ear, giving realistic stereovision images and two- or three-dimensional impression of sounds. As users move their heads, the computer quickly generates new images to reflect what people moving about in a real world would see next. Since head movements result in corresponding changes to what is seen, as they do in real life, this acts as a very powerful mechanism for immersing the user in the virtual world.
What engineering advances are needed?
For virtual reality systems to fully simulate reality effectively, several engineering hurdles must be overcome. The resolution of the video display must be high enough, with fast enough refresh and update rates, for scenes to look like and change like they do in real life. The field of view must be wide enough and the lighting and shadows must be realistic enough to maintain the illusion of a real scene. And for serious simulations, reproducing sensations of sound, touch, and motion are especially critical.
While advances have been made on all of these fronts, virtual reality still falls short of some of its more ambitious depictions. Fine-grained details of the virtual environment are impossible to reproduce precisely. In particular, placing realistic “virtual people” in the scene to interact with the user poses a formidable challenge.
“Rendering of a virtual human that can purposefully interact with a real person — for example, through speech recognition, the generation of meaningful sentences, facial expression, emotion, skin color and tone, and muscle and joint movements — is still beyond the capabilities of real-time computer graphics and artificial intelligence,” write neuroscientist Maria V. Sanchez-Vives and computer scientist Mel Slater. [Sanchez-Vives, p. 335]
Yet virtual reality users routinely respond to even crude “virtual people” as though they are real. So one of the challenges of virtual reality research is identifying just what level of detail is necessary for a user to accept the illusion, in other words to respond to virtual events and simulations in a realistic way. Already, it seems that visually precise detail may not be as important as accurate reproduction of sound and touch.
Touch poses an especially formidable challenge. For some uses, gloves containing sensors can record the movements of a user’s hand and provide tactile feedback, but somewhat crudely. That’s not good enough to train a surgeon who, when cutting through virtual tissue, should feel different degrees of resistance to the motion of a scalpel at different places along the tissue. Moreover, with today’s technology you can’t feel an accidental bump against a virtual piece of furniture.
Efforts to solve such problems are in the beginning stages. One possible approach would make use of electrorheological fluids, which alter their thickness when exposed to electric fields of different strengths. Perhaps an advanced virtual reality computer could make use of this effect to send electrical signals to adjust a glove or garment’s resistance to touch, providing touch feedback to the user.
It may not be virtual reality per se, but a related concept also seems to be growing in cyberspace, as the World Wide Web has become host to whole worlds populated by virtual people guided by their real-world owners. One such site, known as Second Life, already has millions of participants, some who just visit, some who buy virtual property, establish virtual businesses, and communicate and form relationships with other inhabitants through various communication channels.
What’s more, such worlds could be in the process of merging with the real world, as computer records of the physical environment (as available via Google Earth or Microsoft’s Virtual Earth) could be interlaced with the sites like Second Life. It would then be possible to virtually visit real locations, explore a city’s restaurants and hotels, and engage in other virtual tourist activities.
From:http://www.engineeringchallenges.org/cms/8996/9140.aspx
The original:
To most people, virtual reality consists mainly of clever illusions for enhancing computer video games or thickening the plot of science fiction films. Depictions of virtual reality in Hollywood movies range from the crude video-viewing contraption of 1983’s "Brainstorm" to the entire virtual universe known as "The Matrix."
But within many specialized fields, from psychiatry to education, virtual reality is becoming a powerful new tool for training practitioners and treating patients, in addition to its growing use in various forms of entertainment. Virtual reality is already being used in industrial design, for example. Engineers are creating entire cars and airplanes "virtually" in order to test design principles, ergonomics, safety schemes, access for maintenance, and more.
Basically, virtual reality is simply an illusory environment, engineered to give users the impression of being somewhere other than where they are. As you sit safely in your home, virtual reality can transport you to a football game, a rock concert, a submarine exploring the depths of the ocean, or a space station orbiting Jupiter. It allows the user to ride a camel around the Great Pyramids, fly jets, or perform brain surgery.
True virtual reality does more than merely depict scenes of such activities — it creates an illusion of actually being there. Piloting a Boeing 777 with a laptop flight simulator, after all, does not really convey a sense of zooming across the continent 5 miles above the surface of a planet. Virtual reality, though, attempts to re-create the actual experience, combining vision, sound, touch, and feelings of motion engineered to give the brain a realistic set of sensations.
And it works. Studies show that people immersed in a virtual reality scene at the edge of a cliff, for instance, respond realistically — the heart rate rises and the brain resists commands to step over the edge. There are significant social applications as well. It has been shown that people also respond realistically in interactions with life-sized virtual characters, for example exhibiting anxiety when asked to cause pain to a virtual character, even though the user knows it's not a real person and such anxiety makes no rational sense. It is clearly possible to trick the brain into reacting as though an illusory environment were real.
What are the practical applications of virtual reality?
Virtual reality offers a large array of potential uses. Already it has been enlisted to treat people suffering from certain phobias. Exposing people who are afraid of heights to virtual cliff edges has been shown to reduce that fear, in a manner much safer than walking along real cliffs. Similar success has been achieved treating fear of spiders.
Other experiments have tested virtual reality's use in treating social anxieties, such as fear of public speaking, and show that it can be a successful treatment for some more serious disorders, such as post-traumatic stress disorder. Virtual reality also offers advantages for various sorts of research, education, and training. Some neuroscientists believe that virtual reality experiments can provide insight into the nature of awareness and consciousness itself. Surgeons can practice virtual operations before cutting into real people; soldiers can learn combat tactics in virtual worlds without shooting real bullets.
Virtual reality could also be used in business, advancing video conferencing to a level in which people located in widely dispersed parts of the world can interact in a shared environment and carry out tasks together. Meeting the engineering challenge of allowing dispersed people to seamlessly see, hear, and touch each other, as well as share real objects and equipment, would be particularly useful for the military and emergency response teams, too.
All of these scenarios involve outfitting the user with a virtual reality interface — often a display screen mounted on the head so as to cover the eyes and ears — that communicates with a computer. The computer stores all the necessary information to generate the virtual scenes and sounds. Typically, the visual and auditory information is transmitted separately to each eye and ear, giving realistic stereovision images and two- or three-dimensional impression of sounds. As users move their heads, the computer quickly generates new images to reflect what people moving about in a real world would see next. Since head movements result in corresponding changes to what is seen, as they do in real life, this acts as a very powerful mechanism for immersing the user in the virtual world.
What engineering advances are needed?
For virtual reality systems to fully simulate reality effectively, several engineering hurdles must be overcome. The resolution of the video display must be high enough, with fast enough refresh and update rates, for scenes to look like and change like they do in real life. The field of view must be wide enough and the lighting and shadows must be realistic enough to maintain the illusion of a real scene. And for serious simulations, reproducing sensations of sound, touch, and motion are especially critical.
While advances have been made on all of these fronts, virtual reality still falls short of some of its more ambitious depictions. Fine-grained details of the virtual environment are impossible to reproduce precisely. In particular, placing realistic “virtual people” in the scene to interact with the user poses a formidable challenge.
“Rendering of a virtual human that can purposefully interact with a real person — for example, through speech recognition, the generation of meaningful sentences, facial expression, emotion, skin color and tone, and muscle and joint movements — is still beyond the capabilities of real-time computer graphics and artificial intelligence,” write neuroscientist Maria V. Sanchez-Vives and computer scientist Mel Slater. [Sanchez-Vives, p. 335]
Yet virtual reality users routinely respond to even crude “virtual people” as though they are real. So one of the challenges of virtual reality research is identifying just what level of detail is necessary for a user to accept the illusion, in other words to respond to virtual events and simulations in a realistic way. Already, it seems that visually precise detail may not be as important as accurate reproduction of sound and touch.
Touch poses an especially formidable challenge. For some uses, gloves containing sensors can record the movements of a user’s hand and provide tactile feedback, but somewhat crudely. That’s not good enough to train a surgeon who, when cutting through virtual tissue, should feel different degrees of resistance to the motion of a scalpel at different places along the tissue. Moreover, with today’s technology you can’t feel an accidental bump against a virtual piece of furniture.
Efforts to solve such problems are in the beginning stages. One possible approach would make use of electrorheological fluids, which alter their thickness when exposed to electric fields of different strengths. Perhaps an advanced virtual reality computer could make use of this effect to send electrical signals to adjust a glove or garment’s resistance to touch, providing touch feedback to the user.
It may not be virtual reality per se, but a related concept also seems to be growing in cyberspace, as the World Wide Web has become host to whole worlds populated by virtual people guided by their real-world owners. One such site, known as Second Life, already has millions of participants, some who just visit, some who buy virtual property, establish virtual businesses, and communicate and form relationships with other inhabitants through various communication channels.
What’s more, such worlds could be in the process of merging with the real world, as computer records of the physical environment (as available via Google Earth or Microsoft’s Virtual Earth) could be interlaced with the sites like Second Life. It would then be possible to virtually visit real locations, explore a city’s restaurants and hotels, and engage in other virtual tourist activities.
2008年9月9日星期二
The Verb Tenses
Verb Tenses
It is a common sense that no one wants to read an essay filled with mistakes, especially grammar mistakes. Thus students should focus on their grammar mistakes while writing and correct them carefully after ending. The most serious grammar problem for me is the Verb Tenses. There are mainly two reasons for making mistakes.
One is the habit, which is common for basic verb tenses. For example: the simple future, the simple present and the simple past. Students are familiar with these tenses. However, when they are writing an essay, it is hard for them to focus on the verb tenses all the time, thus mistakes coming about. For this situation, students should care more about the basic Tenses and learn to check them after finishing an essay.
Another reason is the unclearly about the tenses. There are some advanced verb tenses that students are not familiar with. For example: the progressive, the perfect, and the perfect progressive. The progressive tenses give the idea that an action is in progress during a particular time and these tenses tells that an action begins before, is in progress during, and continues after another time or action. The perfect tenses give the idea that one thing happens before another time or event. The perfect progressive tenses give the idea that one event is in progress immediately before, up to, until another time or event. These tenses are used to express the duration of the first event. For such verb tenses, students should analyze them carefully and read the paragraph carefully. One basic rule is the correspondence of the context.
Knowing the rules of verb tense is far from enough. Students should do more exercises to strength their memory and improve their analyzing ability. Below is an relevant exercise.
Exercises
Of all man’s natural enemies, the one which has caused him more trouble than any other must be the common rat. For centuries, man (1) ____________ (try), in vain, to solve the problem of rats. The ancient Egyptians (2) ___________ (be) probably the first people to try to get rid of them with poison, and this method (3) _____________ (still be used) today. This says a great deal about how effective this method (4) _____________ (be). We have set innumerable and ingenious traps, from simple wires to complicated machines which drowned the rats in beer! We (5) ___________ (use) gas, water and fire. We have tried to electrocute them and to infect them with specially developed germs. We've even tried to breed super‑cats to kill them. However, we are still losing the battle.
One of the first records we have of the problem of rats was in 1347 when some Italian ships (6) ___________ (carry) rats from the Black Sea back to Italy. Soon, the citizens (7) _____________ (complain) of painful dark marks on their skin. Soon after that, they were dead. This was the beginning of the 'Black Death' which killed 25 million people in only three years. For centuries, the same disease, also called the plague, would wipe out thousands of people from time to time and in different places. Thankfully, this is a problem that man (8) ________________ (almost overcome). Plague today (9) ___________ (be) not the threat it used to be. Only a few countries in the world (10) ___________ (still have) an occasional death caused by the plague. However, the rat is still alive and healthy.
Although the problem of plague has been contained, the rat is still man’s number one enemy. This year, in the United States alone, rats will bite thousands of humans, causing disease, despair and terror. They (11) ___________ (destroy) well over a billion dollars worth of property. In a world constantly suffering from famine, rats will destroy approximately a fifth of all food crops planted. In India alone, they (12) ___________ (deprive) hungry people of enough grain to fill a train more than 2,000 kilometres long. In all of Asia, rats (13) ___________ (eat) 48 million tons of rice a year, enough food to feed a quarter of a billion people. Around the world, rats will spread at least 20 kinds of disease, and in several tropical countries their population will suddenly explode and completely destroy the land.
'When we speak of rats,' (14) ___________ (explain) one leading scientist, 'we are speaking of the most numerous and successful mammal on earth, perhaps including man! When we talk about rat control, we're talking about human survival.'
So why can't man, with all his scientific knowledge, manage to overcome a mere animal like the rat? The answer is simply that the rat isn't a 'mere' animal ‑ it (15) ___________ (be) a very special kind of animal. An average rat can: wriggle through a hole no larger than a S$1 coin; climb a brick wall as if it (16) ___________ (climb) steps; swim for one kilometre and then tread water for three days; chew through lead pipes and metal bars with teeth that can exert an unbelievable 1,691 kilograms per square centimetre; happily leave a building by being flushed down the toilet, and then return the same way; jump from a fifth storey window and run away unharmed; and last but certainly not least, multiply so rapidly that a single pair could have 15,000 babies in one year!!
Perhaps the best example of how 'special' these creatures (17) _________ (be) is found on the island of Engebi, in the Western Pacific. For many years, the United States tested its nuclear weapons on this island. The rat was “completely” destroyed by repeated nuclear explosions. A few years after the explosions (18) ___________ (stop), scientists visited the island and found it was alive with rats. The rats were not injured or weakened in any way. On the contrary, their life spans were longer and, if anything, they were larger and stronger than other rats. It (19) ___________ (seem) that the most deadly weapon that people can create actually (20) ___________ (improve) the health of our oldest enemy!
In addition to all these physical qualities, we also have the problem that rats are rather good at (21) ___________ (not get caught). They seem to have an almost supernatural ability to sense when food (22) ___________ (be poisoned) (even as little as one part in a million) and a suspicious rat will starve before it (23) ___________ (eat) poisoned food. They also seem to be able to recognize a trap with no real difficulty.
To overcome these abilities of the rat, we now use a huge variety of weapons, both sophisticated and simple. We (24) ___________ (experiment) with chemicals, radiation, high‑frequency sound, and even super‑glue! There is now a machine on the market which (25) ___________ (claim) to grab the rat, electrocute it and neatly seal it in a plastic bag. However, the simplest method (26) _________ (be) probably also the oldest, a strong wooden club. It (27) __________ (prove) very effective in Bombay, India. Every night, the rat‑catchers take to the streets armed with such a club. They find a rat with the beam of their torch, crack it over the head, pick it up with their toes and drop it into a sack. In total, they (28) __________ (kill) 4,000 a night, which (29) ____________ (be) a mere drop in the ocean. One thing (30) _________ (look) certain, we had better find a way to defeat these small brown creatures soon, or it may be too late. In the age‑old battle between rats and people, the rats are perhaps beginning to win!
Key to the intermediate level exercises
(1) has been trying, (2) were, (3) is still being used, (4) has been, (5) have used, (6) carried, (7) were complaining (or complained), (8) has almost overcome, (9) is, (10) still have, (11) will destroy, (12) will deprive, (13) eat, (14) explained, (15) is, (16) were climbing, (17) are, (18) had stopped (or stopped), (19) seems, (20) improves, (21) not getting caught, (22) has been poisoned, (23) eats, (24) are experimenting, (25) claims, (26) is, (27) has proved (proves), (28) kill, (29) is, (30) looks.
(slightly adapted from an extract in Burns, J. & Smallwood, I. (1990). Impact 4, McMillan)
It is a common sense that no one wants to read an essay filled with mistakes, especially grammar mistakes. Thus students should focus on their grammar mistakes while writing and correct them carefully after ending. The most serious grammar problem for me is the Verb Tenses. There are mainly two reasons for making mistakes.
One is the habit, which is common for basic verb tenses. For example: the simple future, the simple present and the simple past. Students are familiar with these tenses. However, when they are writing an essay, it is hard for them to focus on the verb tenses all the time, thus mistakes coming about. For this situation, students should care more about the basic Tenses and learn to check them after finishing an essay.
Another reason is the unclearly about the tenses. There are some advanced verb tenses that students are not familiar with. For example: the progressive, the perfect, and the perfect progressive. The progressive tenses give the idea that an action is in progress during a particular time and these tenses tells that an action begins before, is in progress during, and continues after another time or action. The perfect tenses give the idea that one thing happens before another time or event. The perfect progressive tenses give the idea that one event is in progress immediately before, up to, until another time or event. These tenses are used to express the duration of the first event. For such verb tenses, students should analyze them carefully and read the paragraph carefully. One basic rule is the correspondence of the context.
Knowing the rules of verb tense is far from enough. Students should do more exercises to strength their memory and improve their analyzing ability. Below is an relevant exercise.
Exercises
Of all man’s natural enemies, the one which has caused him more trouble than any other must be the common rat. For centuries, man (1) ____________ (try), in vain, to solve the problem of rats. The ancient Egyptians (2) ___________ (be) probably the first people to try to get rid of them with poison, and this method (3) _____________ (still be used) today. This says a great deal about how effective this method (4) _____________ (be). We have set innumerable and ingenious traps, from simple wires to complicated machines which drowned the rats in beer! We (5) ___________ (use) gas, water and fire. We have tried to electrocute them and to infect them with specially developed germs. We've even tried to breed super‑cats to kill them. However, we are still losing the battle.
One of the first records we have of the problem of rats was in 1347 when some Italian ships (6) ___________ (carry) rats from the Black Sea back to Italy. Soon, the citizens (7) _____________ (complain) of painful dark marks on their skin. Soon after that, they were dead. This was the beginning of the 'Black Death' which killed 25 million people in only three years. For centuries, the same disease, also called the plague, would wipe out thousands of people from time to time and in different places. Thankfully, this is a problem that man (8) ________________ (almost overcome). Plague today (9) ___________ (be) not the threat it used to be. Only a few countries in the world (10) ___________ (still have) an occasional death caused by the plague. However, the rat is still alive and healthy.
Although the problem of plague has been contained, the rat is still man’s number one enemy. This year, in the United States alone, rats will bite thousands of humans, causing disease, despair and terror. They (11) ___________ (destroy) well over a billion dollars worth of property. In a world constantly suffering from famine, rats will destroy approximately a fifth of all food crops planted. In India alone, they (12) ___________ (deprive) hungry people of enough grain to fill a train more than 2,000 kilometres long. In all of Asia, rats (13) ___________ (eat) 48 million tons of rice a year, enough food to feed a quarter of a billion people. Around the world, rats will spread at least 20 kinds of disease, and in several tropical countries their population will suddenly explode and completely destroy the land.
'When we speak of rats,' (14) ___________ (explain) one leading scientist, 'we are speaking of the most numerous and successful mammal on earth, perhaps including man! When we talk about rat control, we're talking about human survival.'
So why can't man, with all his scientific knowledge, manage to overcome a mere animal like the rat? The answer is simply that the rat isn't a 'mere' animal ‑ it (15) ___________ (be) a very special kind of animal. An average rat can: wriggle through a hole no larger than a S$1 coin; climb a brick wall as if it (16) ___________ (climb) steps; swim for one kilometre and then tread water for three days; chew through lead pipes and metal bars with teeth that can exert an unbelievable 1,691 kilograms per square centimetre; happily leave a building by being flushed down the toilet, and then return the same way; jump from a fifth storey window and run away unharmed; and last but certainly not least, multiply so rapidly that a single pair could have 15,000 babies in one year!!
Perhaps the best example of how 'special' these creatures (17) _________ (be) is found on the island of Engebi, in the Western Pacific. For many years, the United States tested its nuclear weapons on this island. The rat was “completely” destroyed by repeated nuclear explosions. A few years after the explosions (18) ___________ (stop), scientists visited the island and found it was alive with rats. The rats were not injured or weakened in any way. On the contrary, their life spans were longer and, if anything, they were larger and stronger than other rats. It (19) ___________ (seem) that the most deadly weapon that people can create actually (20) ___________ (improve) the health of our oldest enemy!
In addition to all these physical qualities, we also have the problem that rats are rather good at (21) ___________ (not get caught). They seem to have an almost supernatural ability to sense when food (22) ___________ (be poisoned) (even as little as one part in a million) and a suspicious rat will starve before it (23) ___________ (eat) poisoned food. They also seem to be able to recognize a trap with no real difficulty.
To overcome these abilities of the rat, we now use a huge variety of weapons, both sophisticated and simple. We (24) ___________ (experiment) with chemicals, radiation, high‑frequency sound, and even super‑glue! There is now a machine on the market which (25) ___________ (claim) to grab the rat, electrocute it and neatly seal it in a plastic bag. However, the simplest method (26) _________ (be) probably also the oldest, a strong wooden club. It (27) __________ (prove) very effective in Bombay, India. Every night, the rat‑catchers take to the streets armed with such a club. They find a rat with the beam of their torch, crack it over the head, pick it up with their toes and drop it into a sack. In total, they (28) __________ (kill) 4,000 a night, which (29) ____________ (be) a mere drop in the ocean. One thing (30) _________ (look) certain, we had better find a way to defeat these small brown creatures soon, or it may be too late. In the age‑old battle between rats and people, the rats are perhaps beginning to win!
Key to the intermediate level exercises
(1) has been trying, (2) were, (3) is still being used, (4) has been, (5) have used, (6) carried, (7) were complaining (or complained), (8) has almost overcome, (9) is, (10) still have, (11) will destroy, (12) will deprive, (13) eat, (14) explained, (15) is, (16) were climbing, (17) are, (18) had stopped (or stopped), (19) seems, (20) improves, (21) not getting caught, (22) has been poisoned, (23) eats, (24) are experimenting, (25) claims, (26) is, (27) has proved (proves), (28) kill, (29) is, (30) looks.
(slightly adapted from an extract in Burns, J. & Smallwood, I. (1990). Impact 4, McMillan)
2008年8月26日星期二
Computer-created virtual realities
After reading the Introduction to the Grand Challenges for Engineering by Prof Seeram Ramakrishna, I think the most important idea he mentioned in the article is the Computer-created virtual realities. Reasons are as follows.
First of all, computer-created virtual reality is not only a worldwide issue, but it also connects to the current world tightly. The improving of computer technology and the widely using of Internet facilities has created a really big virtual world for human beings. It is a common sense that such a virtual world brings human beings with lots of entertainment and convenience. It can fulfill human beings both physically and mentally. As a result, the computer-created virtual realities are becoming greater and greater parts of human life.
The second reason is that there are both pros and cons for this topic, thus it becomes very important for human beings to balance it. However, it is not easy to reach the goal as the virtual world is so perfect in some people’s eyes. Sometimes, people will not realize this point even when they are addicted in it. Engineering methods act as very important roles in changing this situation. Thus, the computer-created virtual reality becomes a core issue in the engineering world.
The great importance of computer-created virtual reality and the big venture capital of it push it to the top of the engineering challenges’ list. As the world is still developing so fast and people cannot live without this virtual world, the computer-created virtual world is really an important idea which engineers should focus on and try to improve.
First of all, computer-created virtual reality is not only a worldwide issue, but it also connects to the current world tightly. The improving of computer technology and the widely using of Internet facilities has created a really big virtual world for human beings. It is a common sense that such a virtual world brings human beings with lots of entertainment and convenience. It can fulfill human beings both physically and mentally. As a result, the computer-created virtual realities are becoming greater and greater parts of human life.
The second reason is that there are both pros and cons for this topic, thus it becomes very important for human beings to balance it. However, it is not easy to reach the goal as the virtual world is so perfect in some people’s eyes. Sometimes, people will not realize this point even when they are addicted in it. Engineering methods act as very important roles in changing this situation. Thus, the computer-created virtual reality becomes a core issue in the engineering world.
The great importance of computer-created virtual reality and the big venture capital of it push it to the top of the engineering challenges’ list. As the world is still developing so fast and people cannot live without this virtual world, the computer-created virtual world is really an important idea which engineers should focus on and try to improve.
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