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The Development of Television Technology Radio and television were major agents of social change in the 20th century. Radio was once the center for family entertainment and news. Television enhanced this revolution by adding sight to sound. Both opened the windows to other lives, to remote areas of the world, and to history in the making. News coverage changed from early and late editions of newspapers to broadcast coverage from the scene. Play-by-play sports broadcasts and live concerts enhanced entertainment coverage. For many, the only cultural performances or sports events they would ever hear or see would emanate from the speakers or the screens in their living rooms. Each has engaged millions of people in the major historical events that have shaped the world. If people could look at the sky and see how it is organized into frequency bands used for different purposes, they would be amazed. Radio waves crisscross the atmosphere at the speed of light, relaying incredible amounts of information---navigational data, radio signals, television pictures--using devices for transmission and reception designed, built, and refined by a century of engineers. Key figures in the late 1800s included Nikola Tesla, who developed the Tesla coil, and James Clerk Maxwell and Heinrich Hertz, who proved mathematically the possibility of transmitting electromagnetic signals between widely separated points. It was Guglielmo Marconi who was most responsible for taking the theories of radio waves out of the laboratory and applying them to practical devices. His "wireless" telegraph demonstrated its great potential for worldwide communication in 1901 by sending a signal--the letter "s"--in Morse code a distance of 2,000 miles across the Atlantic Ocean. Radio technology was just around the comer. Immediate engineering challenges addressed the means of transmitting and receiving coded messages, and developing a device that could convert a high frequency oscillating signal into an electric current capable of registering as sound. The first significant development was "the Edison effect", the discovery that the carbon filament in the electric light bulb could radiate a stream of electrons to a nearby test electrode if it had a positive charge. In 1904, Sir John Ambrose Fleming of Britain took this one step further by developing the diode which allowed electric current to be detected by a telephone receiver. Two years later, American Lee De Forest developed the triode, introducing a third electrode (the grid) between the filament and the plate. It could amplify a signal to make live voice broadcasting possible, and was quickly added to Marconi’s wireless telegraph to produce the radio. Radio development was hampered by restrictions placed on airwaves during World War I. Technical limitations were also a problem. Few people had receivers, and those that did had to wear headsets. Radio was seen by many as a hobby for telegraphy buffs. It would take a great deal of engineering before the radio would become the unifying symbol of family entertainment and the medium for news that was its destiny. In the mid-1920s, technical developments expanded transmission distances, radio stations were built across the country, and the performance and appearance of the radio were improved. With tuning circuits, capacitors, microphones, oscillators, and loudspeakers, the industry blossomed in just a decade. By the mid-1930s almost every American household had a radio. The advent of the transistor in the 1950s completely transformed its size, style, and portability. Both television and radar were logical spin-offs of the radio. Almost 50 years before television became a reality, its fundamental principles had been independently developed in Europe, Russia, and the United States. John Baird in England and Charles Jenkins in the United States worked independently to combine modulated light and a scanning wheel to reconstruct a scene in line-by-line sweeps. In 1925, Baird succeeded in transmitting a recognizable image. Philo T. Farnsworth, a 21-year-old inventor from Utah, patented a scanning cathode ray tube, and Vladimir Zworykin of RCA devised a superior television camera in 1930. Regularly scheduled broadcasts started shortly thereafter, and by the early 1940s there were 23 television stations in operation throughout the United States. Shortly after World War Ⅱ, televisions began to appear on the market. The first pictures were faded and flickering, but more than a million sets were sold before the end of the decade. An average set cost $500 at a time when the average salary was less than $3,000 a year. In 1950 engineers perfected the rectangular cathode-ray tube and prices dropped to $200 per set. Within 10 years 45 million units were sold. A study of how human vision works enabled engineers to develop television technology. Images are retained on the retina of a viewer’s eye for a fraction of a second after they strike it. By displaying images piece by piece at sufficient speed, the illusion of a complete picture can be created. By changing the image on the screen 25 to 30 times per second, movement can be realistically represented. Early scanning wheels slowly built a picture line by line. In contrast, each image on a modem color television screen is comprised of more than 100,000 picture elements (pixels), arranged in several hundred lines. The image displayed changes every few hundredths of a second. For a 15-minute newscast, the television must accurately process more than 1 billion units of information. Technical innovations that made this possible included a screen coated with millions of tiny dots of fluorescent compounds that emit light when struck by high-speed electrons. Today this technology is in transition again, moving away from conventional television waves and on to discrete digital signals carried by fiber optics. This holds the potential for making television interactive--allowing a viewer to play a game or order action replays. Cathode ray tubes with power-hungry electron guns are giving way to liquid crystal display (LCD) panels. Movie-style wide screens and flat screens are readily available. Digital signals enable High Definition Television (HDTV) to have almost double the usual number of pixels, giving a much sharper picture. The advent of cable television and advances in fiber-optic technology will also help lift the present bandwidth restrictions and increase image quality. The problem of bandwidth currently can be solved with the appearance of ______ and advances in fiber-optic technology.
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10 Skills You Need to Succeed at Almost Anything What does it take to succeed. A positive attitude Well, sure, but that’s hardly enough. The Law of Attraction The Secret These ideas might act as spurs to action, but without the action itself, they don’t do much. Success, however, it’s defined, takes action, and taking good and appropriate action takes skills. Some of these skills (not enough, though) are taught in school (not well enough, either), others are taught on the job, and still others we learn from general life experience. Below is a list of general skills that will help anyone get ahead in practically any field, from running a company to running a gardening club. Of course, there are skills specific to each field as well--but my concern here is with the skills that translate across disciplines, the ones that can be learned by anyone in any position. 1. Public Speaking The ability to speak clearly, persuasively, and forcefully in front of an audience--whether an audience of one or of thousands--is one of the most important skills anyone can develop. People who are effective speakers come across as more comfortable with themselves, more confident, and more attractive to be around. Being able to speak effectively means you can sell anything--products, of course, but also ideas, ideologies, worldview, and yourself--which means more opportunities for career advancement, bigger clients, or business funding. 2. Writing Writing well offers many of the same advantages that speaking well offers: good writers are better at selling products, ideas, and themselves than poor writers. Learning to write well involves not just mastery of grammar but the development of the ability to organize one’s thoughts into a coherent form and target it to an audience in the most effective way possible. Given the huge amount of text generated by almost every transaction--from court briefs and legislation running into the thousands of pages to those foot-long receipts you get when you buy gum these days--a person who is a master of the written word can expect doors to open in just about every field. 3. Self-management If success depends on effective action, effective action depends on the ability to focus your attention where it is needed most, when it is needed most. Strong organizational skills, effective productivity habits, and a strong sense of discipline are needed to keep yourself on track. 4. Networking Networking is not only for finding jobs or clients. In an economy dominated by ideas and innovation, networking creates the channel through which ideas flow and in which new ideas are created. A large network, carefully cultivated, ties one into not just a body of people but a body of relationships, and those relationships are more than just the sum of their parts. The interactions those relationships make possible give rise to innovation and creativity--and provide the support to nurture new ideas until they can be realized. 5. Critical Thinking We are exposed to hundreds, if not thousands, of times more information on a daily basis than our great-grandparents were. Being able to evaluate that information, sort the potentially valuable from the trivial, analyze its relevance and meaning, and relate it to other information is crucial--and woefully under-taught. Good critical thinking skills immediately distinguish you from the mass of people these days. 6. Decision-Making The bridge that leads from analysis to action is effective decision-making--knowing what to do based on the information available. While not being critical can be dangerous, so too can over-analyzing, or waiting for more information before making a decision. Being able to take in the scene and respond quickly and effectively is what separates the doers from the wannabes. 7. Math You don’t have to be able to integrate polynomials (多项式) to be successful. However, the ability to quickly work with figures in your head, to make rough but fairly accurate estimates, and to understand things like compound interest and basic statistics gives you a big lead on most people. All of these skills will help you to analyze data more effectively--and more quickly--and to make better decisions based on it. 8. Research Nobody can be expected to know everything, or even a tiny fraction of everything. Even within your field, chances are there’s tar more that you don’t know than you do know. You don’t have to know everything--but you should be able to quickly and painlessly find out what you need to know. That means learning to use the Internet effectively, learning to use a library, learning to read productively, and learning how to leverage your network of contacts--and what kinds of research are going to work best in any given situation. 9. Relaxation Stress will not only kill you, it leads to poor decision-making, poor thinking, and poor socialization. So be failing to relax, you knock out at least three of the skills in this list--and really more. Plus, working yourself to death in order to keep up, and not having any time to enjoy the fruits of your work, isn’t really "success". It’s obsession. Being able to face even the most pressing crises with your wits about you and in the most productive way is possibly the most important thing on this list. 10. Basic Accounting It is a simple fact in our society that money is necessary. Even the simple pleasures in life, like hugging your child, ultimately need money--or you’re not going to survive to hug for very long. Knowing how to track and record your expenses and income is important just to survive, let alone to thrive. But more than that, the principles of accounting apply more widely to things like tracking the time you spend on a project or determining whether the value of an action outweighs the costs in money, time, and effort. It’s a shame that basic accounting isn’t a required part of the core K-12 curriculum. According to the author, it is a pity that ______ isn’t considered important in K-12 curriculum.
The Science of Memory: An Infinite Loop in the Brain Jill Price can rattle off, without hesitation, what she saw and heard on almost any given date. She remembers many early childhood experiences and most of the days between the ages of 9 and 15. There are virtually no gaps in her memory. She can also date events that were reported in the media, provided she heard about them at the time. When and where did the Concorde crash When was O.J. Simpson arrested When did the second Gulf War begin Price doesn’t even have to stop and think. She can effortlessly recite the dates, numbers and entire stories. "People say to me: Oh, how fascinating, it must be a treat to have a perfect memory," she says. Her lips twist into a thin smile. "But it’s also agonizing." In addition to good memories, every angry word, every mistake, every disappointment, every shock and every moment of pain goes unforgotten. Time heals no wounds for Price. "I don’t look back at the past with any distance. It’s more like experiencing everything over and over again, and those memories trigger exactly the same emotions in me. It’s like an endless, chaotic film that can completely overpower me. And there’s no stop button." Can someone who cannot forget even fall in love Can they forgive, either others or themselves Price’s life has had its share of suffering, including family strife, her mother’s cancer and, later, the sudden death of her husband Jim. Because she was hounded by bad memories, grew depressed and feared that she was going crazy, she sat in front of her computer on June 5, 2000 and typed a single word into Google: memory. That was how Price found James McGaugh, and became part of a scientific case study. McGaugh is one of the leading experts on memory in the United States. He founded the Center for the Neurobiology of Learning and Memory at the University of California in Irvine. "I was skeptical, of course, when Jill told me her story," says McGaugh, a slim, grey-haired man with glasses. "But I’ve spent most of my life studying the mechanisms in the brain that are associated with the development of lasting memories. So I thought that I should at least meet the woman." McGaugh and his staff realized they were looking at an exotic case, perhaps even a scientific sensation. For that reason they took a thorough approach, and for five years they subjected Price to batteries of neuropsychological (神经心理学 ) tests, combed the professional literature for similar cases and developed special questionnaires to allow them to test her memory. Once she was asked to write down the dates of all Easter holidays from 1980 to 2003. "It took her 10 minutes, and she only got one of the 24 dates wrong, where she was off by two days," says McGaugh. He had Price repeat the test two years later, and the second time she got all the dates right. "I thought that was especially impressive," says McGaugh, "because she is Jewish. Easter means nothing to her." McGaugh and his colleagues concluded that Price’s episodic memory, her recollection of personal experiences and the emotions associated with them, is virtually perfect. A case like this has never been described in the history of memory research, according to McGaugh. He explains that Price differs substantially from other people with special powers of recall, such as autistic savants(自闭学者), because she uses no strategies to help her remember and even does a surprisingly poor job on some memory tests. It’s difficult for her to memorize poems or series of numbers--which helps explain why she never stood out in school. Her semantic memory, the ability to remember facts not directly related to everyday life, is only average. Two years ago, the scientists published their first conclusions in a professional journal without revealing the identity of their subject. Since then, more than 200 people have contacted McGaugh, all claiming to have an equally perfect episodic memory. Most of them were exposed as fakes. Three did appear to have similarly astonishing abilities. "Their personalities are very different. The others are not as anxious as Jill. But they achieve comparable results in the tests," McGaugh reports. The subjects do have certain compulsive traits in common, says McGaugh, especially compulsive hoarding. In neurobiological terms, a memory is a stored pattern of links between nerve cells in the brain. It is created when synapses in a network of neurons are activated for a short time. The more often the memory is recalled afterwards, the more likely it is that permanent links develop between the nerve cells--and the pattern will be stored as a long-term memory. In theory there are so many possible links that an almost unlimited number of memories can be permanently stored. So why don’t all people have the same powers of recollection as Jill Price "If we could remember everything equally well, the brain would be hopelessly overburdened and would operate more slowly," says McGaugh. He says forgetting is a necessary condition of having a viable memory--except in the case of Price and the other three memory superstars. For McGaugh, there is another reason why people with such phenomenal memory are so puzzling. They challenge a theory on which his research has been based for the last half a century. This theory, based on clinical observation, says memories are stored in greater detail and with more staying power when they are tied to emotion. Sensations are emotionally processed in the amygdala, a specific part of the brain’s limbic system. There decisions are made as to which information should remain in long-term memory. The more powerfully the amygdala is activated, the greater the likelihood of a permanent memory. "But now here we have these four people who seem to violate this principle, because they also remember the most banal and inconsequential things," says McGaugh. For common people, ______ is a necessary condition of having a viable memory.
The Development of Television Technology Radio and television were major agents of social change in the 20th century. Radio was once the center for family entertainment and news. Television enhanced this revolution by adding sight to sound. Both opened the windows to other lives, to remote areas of the world, and to history in the making. News coverage changed from early and late editions of newspapers to broadcast coverage from the scene. Play-by-play sports broadcasts and live concerts enhanced entertainment coverage. For many, the only cultural performances or sports events they would ever hear or see would emanate from the speakers or the screens in their living rooms. Each has engaged millions of people in the major historical events that have shaped the world. If people could look at the sky and see how it is organized into frequency bands used for different purposes, they would be amazed. Radio waves crisscross the atmosphere at the speed of light, relaying incredible amounts of information---navigational data, radio signals, television pictures--using devices for transmission and reception designed, built, and refined by a century of engineers. Key figures in the late 1800s included Nikola Tesla, who developed the Tesla coil, and James Clerk Maxwell and Heinrich Hertz, who proved mathematically the possibility of transmitting electromagnetic signals between widely separated points. It was Guglielmo Marconi who was most responsible for taking the theories of radio waves out of the laboratory and applying them to practical devices. His "wireless" telegraph demonstrated its great potential for worldwide communication in 1901 by sending a signal--the letter "s"--in Morse code a distance of 2,000 miles across the Atlantic Ocean. Radio technology was just around the comer. Immediate engineering challenges addressed the means of transmitting and receiving coded messages, and developing a device that could convert a high frequency oscillating signal into an electric current capable of registering as sound. The first significant development was "the Edison effect", the discovery that the carbon filament in the electric light bulb could radiate a stream of electrons to a nearby test electrode if it had a positive charge. In 1904, Sir John Ambrose Fleming of Britain took this one step further by developing the diode which allowed electric current to be detected by a telephone receiver. Two years later, American Lee De Forest developed the triode, introducing a third electrode (the grid) between the filament and the plate. It could amplify a signal to make live voice broadcasting possible, and was quickly added to Marconi’s wireless telegraph to produce the radio. Radio development was hampered by restrictions placed on airwaves during World War I. Technical limitations were also a problem. Few people had receivers, and those that did had to wear headsets. Radio was seen by many as a hobby for telegraphy buffs. It would take a great deal of engineering before the radio would become the unifying symbol of family entertainment and the medium for news that was its destiny. In the mid-1920s, technical developments expanded transmission distances, radio stations were built across the country, and the performance and appearance of the radio were improved. With tuning circuits, capacitors, microphones, oscillators, and loudspeakers, the industry blossomed in just a decade. By the mid-1930s almost every American household had a radio. The advent of the transistor in the 1950s completely transformed its size, style, and portability. Both television and radar were logical spin-offs of the radio. Almost 50 years before television became a reality, its fundamental principles had been independently developed in Europe, Russia, and the United States. John Baird in England and Charles Jenkins in the United States worked independently to combine modulated light and a scanning wheel to reconstruct a scene in line-by-line sweeps. In 1925, Baird succeeded in transmitting a recognizable image. Philo T. Farnsworth, a 21-year-old inventor from Utah, patented a scanning cathode ray tube, and Vladimir Zworykin of RCA devised a superior television camera in 1930. Regularly scheduled broadcasts started shortly thereafter, and by the early 1940s there were 23 television stations in operation throughout the United States. Shortly after World War Ⅱ, televisions began to appear on the market. The first pictures were faded and flickering, but more than a million sets were sold before the end of the decade. An average set cost $500 at a time when the average salary was less than $3,000 a year. In 1950 engineers perfected the rectangular cathode-ray tube and prices dropped to $200 per set. Within 10 years 45 million units were sold. A study of how human vision works enabled engineers to develop television technology. Images are retained on the retina of a viewer’s eye for a fraction of a second after they strike it. By displaying images piece by piece at sufficient speed, the illusion of a complete picture can be created. By changing the image on the screen 25 to 30 times per second, movement can be realistically represented. Early scanning wheels slowly built a picture line by line. In contrast, each image on a modem color television screen is comprised of more than 100,000 picture elements (pixels), arranged in several hundred lines. The image displayed changes every few hundredths of a second. For a 15-minute newscast, the television must accurately process more than 1 billion units of information. Technical innovations that made this possible included a screen coated with millions of tiny dots of fluorescent compounds that emit light when struck by high-speed electrons. Today this technology is in transition again, moving away from conventional television waves and on to discrete digital signals carried by fiber optics. This holds the potential for making television interactive--allowing a viewer to play a game or order action replays. Cathode ray tubes with power-hungry electron guns are giving way to liquid crystal display (LCD) panels. Movie-style wide screens and flat screens are readily available. Digital signals enable High Definition Television (HDTV) to have almost double the usual number of pixels, giving a much sharper picture. The advent of cable television and advances in fiber-optic technology will also help lift the present bandwidth restrictions and increase image quality. This passage discusses the technological development of radio and ______.
Seven Financial Tips from the Great Depression Having lived through the Depression, our grandparents and great-grandparents formed a lack of trust in banks and turned to burying cash in the backyard or hiding it under the mattress. Our current economic downturn doesn’t yet call for such drastic measures but there are things we can learn from those who went through this challenging era and prospered. Food: Grow a Garden Growing at least some of your own food can save a lot of money, and provide the satisfaction that comes from eating local, really local. Consider starting a community garden such as the Depression-era community relief gardens, or the World War II Victory Gardens, searching step-by-step instructions on the Internet, and applying those ideas to any project that you can implement on someone’s vacant lot (with permission ). Entertainment: Enjoying the Simple Things Not everything about the Depression was actually depressing. In hard times, we can sometimes find a lot of pleasure in remembering to enjoy the simple things in life. During the 1930s, games like Monopoly became popular because they gave people hope and allowed them to dream of a better life. Remember some of the board games from your childhood, and plan a low-tech outing with friends and family. It will also help you remember that you don’t absolutely need every single gadget (小玩意) that hits the store shelves, and on top of that it will be a bit cheaper than spending the day at Disneyland. Transportation: How Many SUVs Does Your Family Need Hitchhiking (搭乘) was prevalent in the Great Depression, and this is one area that can at least offer some creativity, although Mint absolutely does not recommend that you sell your car and get to work each day by holding up a thumb next to the freeway, nor should you become a hobohemian (流浪汉) and hop trains to get around. However, since owning a car is more of a luxury than a necessity, we can learn from the community aspect and form carpools, walk to the store if it’s only a mile away, and if you are lucky enough to have a half-decent public transportation system, Google Maps now shows your time and cost to drive relative to taking a bus or walking. Consider moving closer to where you work and walk or ride a bike instead. Like Dave Ramsey, author of Total Money Makeover, says: "If you are willing to live like no one else now, you can live like no one else later."Essentially, by defying convention, even for a relatively short amount of time, you can save a hefty sum of money. Housing: Downsize or Rent a Room We all have different situations, and this is one of the most pressing issues facing our nation and the world right now. You might be just out of college and trying to make it on your own, or you might be paying for your child’s college now, but there are definitely lessons to be learned from the Depression. In some cases, it may be beneficial to sacrifice a bit of privacy in the short-term in order to get back on track (回 到正轨) financially. Rent an extra bedroom to a friend, have your child move back home if you are struggling to send him or her rent money every month, or downsize your home. You don’t have to necessarily make a gut-wrenching (搜肠刮肚的) decision overnight, but do yourself a favor and at least check out some listings on Craigslist for rentals, or have a real estate agent e-mail you listings in a cheaper price range. If a great deal pops up that piques your interest, you can at least bat around the idea with your family. If you are single, just go for it! Jobs/Entrepreneurship: Nothing Left to Lose Due to the extensive public works projects in the 1930s, there was at least a bit of relief for the unemployed masses. People simply took any work they could, and often worked 12 hour days. If you are looking for employment, you might consider looking for a position that is slightly below your ideal salary, but that seems to have the most potential for advancement. If you are entrepreneurial, and perhaps have already fallen behind on bills, one positive thing about the current economic climate is that you are starting over at a time when many other people are also faced with starting from scratch (白手起家) financially, and perhaps you may even be in a position where you literally have nothing left to lose, which can be a great time for personal innovation and taking the risk to start in a new industry or implement an idea that’s always been in the back of your mind. It’s time for boot-strapping(步步为营法) ! Credit: Redefining What You Can Afford and Need If you have credit available, you might be tempted to use it before the bank cuts the credit line. Don’t do it. Going into debt will only hurt you in the long run. Instead, remember the words of your grandmother and heed this simple, age-old advice--"if you can’t afford to pay cash, you can’t afford it". Money Management/Budgeting: Simplify Your System When you simply have no money, it is easy to keep spending under control because it is impossible to spend. In many cases, one spouse saved money in the cupboard and even hid it from the other spouse. There is a good trick to be found here that requires a lot of discipline. If, for example, you are getting hit with overdraft ( 透支) fees, you need to establish a barrier that you absolutely will not dip below (even if it means paying a bill late). Take the cue from the 1930s and use cash rather than debit for your petty purchases, especially when you are close to zero in your account. This will help avoid paying $36 for that pack of gum if an unexpected payment goes through your account and causes an overdraft fee. For our grandparents and great-grandparents who lived through the 1930s, many months surely consisted of living in survival mode, and there were much fewer recurring expenses and bills to be paid, so it was possible in a lot of cases to keep track of spending without even necessarily writing it down. Today, we have several types of accounts, in many cases at different institutions, with new types of debt and monthly payments to keep track of, so take a look at Mint’s free software today and start tracking your spending automatically to find areas where you can save money. Comparing with those who lived through the 1930s, today we have new types of debt and ______ to keep track of.
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