The changing profile of a city in the United States is apparent in the shifting definitions used by the United States Bureau of the Census. In 1870 the census officially distinguished the nation’s "urban" from its "rural" population for the first time. "Urban population" was defined as persons living in towns of 8,000 inhabitants or more. But after 1900 it meant persons living in incorporated places having 2,500 or more inhabitants. Then, in 1950 the Census Bureau radically changed its definition of "urban" to, take account of the new vagueness of city boundaries. In addition to persons living in incorporated units of 2,500 or more, the census now included those who lived in unincorporated units of that size, and also all persons living in the densely settled urban fringe, including both incorporated and unincorporated areas located around cities of 50, 000 inhabitants or more. Each such unit, conceived as an integrated economic and social unit with a large population nucleus, was named a Standard Metropolitan Statistical Area (SMSA). Each SMSA would contain at least one central city with 50,000 inhabitants or more or two cities having shared boundaries and constituting, for general economic and social purposes, a single community with a combined population of at least 50,000, the smaller of which must have a population of at least 15,000. Such an area included the country in which the central city is located, and adjacent countries that are found to be metropolitan in character and economically and socially integrated with the country of the central city. By 1970, about two-thirds of the population of the United States was living in these urbanized areas, and of that figure more than half were living outside the central cities. While the Census Bureau and the United States government used the term SMSA (by 1969 there were 233 of them), social scientists were also using new terms to describe the elusive, vaguely defined areas reaching out from what used to be simple "towns" and "cities". A host of terms came into use: "metropolitan regions", "polynucleated population groups", "conurbations", "metropolitan clusters", "megalopolises", and so on. Which of the following is NOT true of an SMSA
A. It has a population of at least 50,000.
B. It can include a city’s outlying regions.
C. It can include unincorporated regions.
D. It consists of at least two cities.
案例分析题Temperatures (温度) around the world are going up year after year. A report shows that the ten warmest years since 1860 all happened after 1987. Of those ten, nine happened after 1990. The report also says the increase (上升) in temperature over the past 25 years is greater than that over the past 1,000 years. Ken Davidson, a world-famous scientist, agrees with the scientific findings that global (全球的) warming is happening just because of what people do on the earth. He says one of the most important reasons for the higher temperatures is the fact that cities are getting bigger and bigger. Studies show that cities are hotter than other places. Reports show that many places around the world have had unusual weather in the past few years because of global warming. Most of Asia, for example, is warmer than before, and in India hundreds of people have even died from the hot and dry weather each year. Parts of Africa have often had unusually heavy rains while other parts of Africa have had unusually dry weather. In parts of Europe, more than 100 people died from heavy rainfall in September 2002. Yet large parts of North and South America had very dry weather in the same year. What was the weather like in most of North and South America in 2002()
A. It was cold.
B. It was wet.
C. It was dry.
There are two ways to create colors in a photograph. One method, called addtive, starts with three basic colors and adds them together to produce some other color. The second method, called subtractive, starts with white light (a mixtu re of all colors in the spectrum) and, by taking away some or all other colors, leaves the one desired. In the additive method, separate colored lights combine to produce various other colors. The three additive primary colors are green, red and blue (each providing about one third of the wavelengths in the total spectrum). Mixed in varying proportions, they can produce all colors. Green and red light mix to produce yellow; red and blue light mix to produce magenta; green and blue mix to produce cyan. When equal parts of all three of these primary colored beams of light overlap, the mixture appears white to the eye. In the subtractive process colors are produced when dye (as in paint or color photographic materials) absorbs some wavelengths and so passes on only part of the spectrum. The subtractive primaries are cyan (a bluish green), magenta (a purplish pink) and yellow; these additive primaries or dyes that absorb red, green and blue wavelengths respectively, thus subtracting them from white light. These dye colors are the complementary colors to the three additive primaries of red, green, and blue. Properly combined, the subtractive primaries can absorb all colors of light, producing black. But, mixed in varying proportions, they too can produce any color in the spectrum. Whether a particular color is obtained by adding colored lights together or by subtracting some light from the total spectrum. The result looks the same to the eye. The additive process was employed for early color photography. But the subtractive method, while requiring complex chemical techniques, has turned out to be more practical and is the basis of all modern color films. Which of the following is closest in meaning to the phrase "passes on" as used in paragraph 3
A. Judges.
B. Lets through.
C. Dies.
D. Goes over.
The idea of humanoid robots is not new. They have been part of the imaginative landscape ever since Karl Capek, a Czech writer, first dreamed them up for his 1921 play "Possum’s Universal Robots". (The word "robot" comes from the Czech word for drugery, robota. ) Since then. Hollywood has produced countless variations on the theme, from the sultry False Myria in Fritz Lang’s silent masterpiece "Metropolis" to the withering C3PO in "Star Wars" and the ruthless assassin of "Terminator". Humanoid robots have walked into our collective subconscious, coloring our views of the future. But now Japan’s industrial giants are spending billions of yen to make such robots a reality Their new humanoids represent impressive feats of engineering: when Honda introduced Asimo, a four-foot robot that had been in development for some 15 years, it walked so fluidly that its white articulated exterior seemed to conceal a human. Honda continues to make the machine faster, friendlier and more agile. Last October, when Asimo was inducted into the Robot Hall of Fame in Pittsburgh, it walked onto the stage and accepted its own plaque. At two and a half feet tall, Sony’s QRIO is smaller and more toy-like than Asimo. It walks, understands a small number of voice commands, and can navigate on its own. If it falls over, it gets up and resumes where it left off. It can even connect wirelessly to the Internet and broadcast what its camera eyes can see. In 2003, Sony demonsrated an upgraded QRIO that could run. Honda responded last December with a version of Asimo that runs at twice the speed. In 2004, Toyota joined the fray with its own family of robots, called Partner, one of which is a four-foot humanoid that plays the trumpet. Its fingers work the instrument’s valves, and it has mechanical lungs and artificial lips. Toyota hopes to offer a commercial version of the robot by 2010. This month, 50 Partner robots will act as guides at Expo 2005 In Aichi, Japan. Despite their sudden proliferation, however, humanoids are still a mechanical minority. Most of the world’s robots are faceless, footless and mute. They are bolted to the floors of factories, stamping out car parts or welding pieces of metal, making more machines. According to the United Nations, business orders for industrial robots jumped 18% in the first half of 2004. They may soon be outnumbered by domestic robots, such as self-navigating vacuum cleaners, lawn mowers and window washers, which are selling fast. But neither industrial nor domestic robots are humanoid. Sony’s QRIO coul perform all the following tasks EXCEPT ______.
A. walking everywhere freely
B. understanding some words uttered by people
C. finding its way
D. continuing walking after it stumbles