In the 1920s demand for American farm products fell, as European countries began to recover from World War I and instituted austerity programs to reduce their imports. The result was a sharp drop in farm prices. This period was more disastrous for farmers than earlier times had been, because farmers were no longer self-sufficient. They were paying for machinery, seed, and fertilizer, and they were also buying consumer goods. The prices of the items farmers bought remained constant, while prices they received for their products fell. These developments were made worse by the Great Depression, which began in 1929 and extended throughout the 1939s.
In 1929, under President Herbert Hoover, the Federal Farm Board was organized. It established the principle of direct interference with supply and demand, and it represented the first national commitment to provide greater economic stability for farmers.
President Hoovers successor attached even more importance to this problem. One of the first measures proposed by President Franklin D. Roosevelt when he took office in 1933 was the Agricultural Adjustment Act, which was subsequently passed by Congress. This law gave the Secretary of Agriculture the power to reduce production through voluntary agreements with farmers who were paid to take their land out of use. A deliberate scarcity of farm products was planned in an effort to raise prices. This law was declared unconstitutional by the Supreme Court on the grounds that general taxes were being collected to pay one special group of people. However, new laws were passed immediately that achieved the same result of resting soil and providing flood-control measures, but which were based on the principle of soil conservation. The Roosevelt Administration believed that rebuilding the nations soil was in the national interest and was not simply a plan to help farmers at the expense of other citizens. Later the government guaranteed loans to farmers so that they could buy farm machinery, hybrid grain, and fertilizers.
26.The author says that the powerful computers of today ______.
A) are capable of reliably recognizing the shape of an object
B) are close to exhibiting humanlike behavior
C) are not very different in their performance from those of the 50s
D) still cannot communicate with people in a human language
27.The new trend in artificial intelligence research stems from ______.
A) the shift of the focus of study on to the recognition of the shapes of objects
B) the belief that human intelligence cannot be duplicated with logical, step-by-step programs
C) the aspirations of scientists to duplicate the intelligence of a ten-month-old child
D) the efforts made by scientists in the study of the similarities between transistors and brain cells
28.Conrad and his group of AI researchers have been making enormous efforts to ______.
A) find a roundabout way to design powerful computers
B) build a computer using a clever network of switches
C) find out how intelligence developed in nature
D) separate the highest and most abstract levels of thought
29.Whats the authors opinion about the new AI movement?
A) It has created a sensation among artificial intelligence researchers but will soon die out.
B) Its a breakthrough in duplicating human thought processes.
C) Its more like a peculiar game rather than a real scientific effort.
D) It may prove to be in the right direction though nobody is sure of its future prospects.
30.Which of the following is closest in meaning to the phrase the only game in town ?
A) The only approach to building an artificially intelligent computer.
B) The only way for them to win a prize in artificial intelligence research.
C) The only area worth studying in computer science.
D) The only game they would like to play in town.
In the 1950s, the pioneers of artificial intelligence predicted that, by the end of this century, computers would be conversing with us at work and robots would be performing our housework. But as useful as computers are, theyre nowhere close to achieving anything remotely resembling these early aspirations for humanlike behavior. Never mind something as complex as conversation: the most powerful computers struggle to reliably recognize the shape of an object, the most elementary of tasks for a ten-month-old kid.
A growing group of AI researchers think they know where the field went wrong. The problem, the scientists say, is that AI has been trying to separate the highest, most abstract levels of thought, like language and mathematics, and to duplicate them with logical, step-by-step programs. A new movement in AI, on the other hand, takes a closer look at the more roundabout way in which nature came up with intelligence. Many of these researchers study evolution and natural adaptation instead of formal logic and conventional computer programs. Rather than digital computers and transistors, some want to work with brain cells and proteins. The results of these early efforts are as promising as they are peculiar, and the new nature-based AI movement is slowly but surely moving to the forefront of the field.
Imitating the brains neural network is a huge step in the right direction, says computer scientist and biophysicist Michael Conrad, but it still misses an important aspect of natural intelligence. People tend to treat the brain as if it were made up of color-coded transistors, he explains, but its not simply a clever network of switches. There are lots of important things going on inside the brain cells themselves. Specifically, Conrad believes that many of the brains capabilities stem from the pattern recognition proficiency of the individual molecules that make up each brain cell. The best way to build and artificially intelligent device, he claims, would be to build it around the same sort of molecular skills.
Right now, the notion that conventional computers and software are fundamentally incapable of matching the processes that take place in the brain remains controversial. But if it proves true, then the efforts of Conrad and his fellow AI rebels could turn out to be the only game in town.
11. A new study on birds sleep has revealed that ____________.
A) half-brain sleep is found in a wide variety of birds
B) half-brain sleep is characterized by slow brain waves
C) birds can control their half-brain sleep consciously
D) birds seldom sleep with the whole of their brain at rest
12. According to the passage, birds often half sleep because ______________.
A) they have to watch out for possible attacks
B) their brain hemisphere take turns to rest 跨段
C) the two halves of their brain are differently structured 没
D) they have to constantly keep an eye on their companions 反
13. The example of a bird sleeping in front of a mirror indicates that _____________.
A) the phenomenon of birds dozing in pairs is widespread
B) birds prefer to sleep in pairs for the sake of security
C) even an imagined companion gives the bird a sense of security
D) a single pet bird enjoys seeing its own reflection in the mirror
14. While sleeping, some water mammals tend to keep half awake in order to __________.
A) alert themselves to the approaching enemy
B) emerge from water now and then to breathe
C) be sensitive to the ever-changing environment
D) avoid being swept away by rapid currents
15. By just the tip of the iceberg , Siegel suggests that ____________.
A) half-brain sleep has something to do with icy weather
B) the mystery of half-brain sleep is close to being solved
C) most birds living in cold regions tend to be half sleepers
D) half-brain sleep is a phenomenon that could exist among other species