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The goal of smart-highway technology is to make traffic systems work at optimum efficiency by treating the road and the vehicles traveling on them as an integral transportation system. Proponents of the advanced technology say electronic detection systems, closed-circuit television, radio-communication, ramp metering variable message signing, and other smart-highway technology can now be used at a reasonable cost to improve communication between drivers and the people who monitor traffic②.
Pathfinder, a Santa Monica, California-based smart-highway project in which a 14-mile stretch of the Santa Monica Freeway, making up what is called a "smart corridor," is being instrumented with buried loops in the pavement. Closed-circuit television cameras survey the flow of traffic; while communication linked to property equipped automobiles advise motorists of the least congested routes or detours.
Not all traffic experts, however, look to smart-highway technology as the ultimate solution to traffic gridlock. Some say the high-tech approach is limited and can only offer temporary solutions to a serious problem.
"Electronics on the highway addresses just one aspects of the problem: how to regulate traffic more efficiently," explains Michael Renner, senior researcher at the world-watch Institute. "It does not deal with the central problem of too many cars for roads that cannot be built fast enough. It sends people the wrong message. They start thinking 'yes, there used to be a traffic congestion problem, but that's been solved now because we have advanced high-tech system in place." Larson agrees and adds, "Smart highway is just one of the tools that we use to deal with our traffic problems. It is not the solution itself, just pan of package. There are different strategies."
Other traffic problem-solving options being studied and experimented with include car-pooling, rapid mass-transit systems, staggered or flexible work hours and road pricing, a system whereby motorists pay a certain amount for the time they use a highway③.
It seems that we need a new, major thrust to deal with the traffic problems of the next 20 years. There has to be a big change and a long way to go.
The compound word "quick-fix' (Line 2, Para. 1 ) is closest in meaning to ______.
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As long as the resources we consumed each year came primarily from within our own boundaries, this was largely an internal matter. But as our resources come more and more from the outside world, "outsiders'' are going to have some stay over the rate at which and terms under which we consume. We will no longer be able to think in terms of "our" resources and "their" resources, but only of common resources.
As Americans consuming such a disproportionate share of the world's resources, we have to question whether or not we can continue our pursuit of super affluence in a world of scarcity. We are now reaching the point where we must carefully examine the presumed link between our level of well-being and the level of material goods consumed. If you have only one crust of bread, then an additional crust of bread doesn't make that much different. In the eyes of most of the world today, Americans have their loaf of bread and are asking for still more. People elsewhere are beginning to ask why. This is the question we're going to have to answer, whether we're trying to persuade countries to step up their exports of oil to us or trying to convince them that we ought to be permitted to maintain our share of the world fish catch②.
The prospect of a scarcity of, and competition for, the world's resources require that we reexamine the way in which we relate to the rest of the world. It means we find ways of cutting back on resource consumption that is dependent on the resources and cooperation of other countries. We cannot expect people in these countries to concern themselves with our worsening energy and food shortages unless we demonstrate some concern for the hunger, illiteracy and disease that are diminishing life for them③.
The writer warns Americans that ______.
The millions of calculations involved, ______ by hand, would have lost all practical value
Football playing will continue to be ______ it is today—the most popular game for boys in
The evolution of sex ratio has produced, in most plants and animals with separate sexes, approximately equal numbers of males and females. Why should this be so？ Two main kinds of answers have been offered. One is couched in terms of advantage to population. It is argued that the sex ratio will evolve so as to maximize the number of meetings between individuals of the opposite sex. This is essentially a "group selection" argument. The other, and in my view correct, type of answer was first put forward by Fisher in 1930. This "genetic" argument starts from the assumption that genes can influence the relative numbers of male and female offspring produced by an individual carrying the genes①. That sex ratio will be favored which maximizes the number of descendants an individual will have and hence the number of gene copies transmitted. Suppose that the population consisted mostly of females, and then an individual who produced sons only would have more grandchildren. In contrast, if the population consisted mostly of males, it would pay to have daughters. If, however, the population consisted of equal numbers of males and females, sons and daughters would be equally valuable. Thus a one-to-one sex ratio is the only stable ratio; it is an "evolutionarily stable strategy". Although Fisher wrote before the mathematical theory of games had been developed, his theory incorporated the essential feature of a game that the best strategy to adopt depends on what others are doing.
Since Fisher's time, it has been realized that genes can sometimes influence the chromosome or gamete in which they find themselves so that the gamete will be more likely to participate in fertilization②. If such a gene occurs on a sex-determining (X or Y) chromosome, then highly aberrant sex ratios can occur. But more immediately relevant to game theory are the sex ratios in certain parasitic wasp species that have a large excess of females. In these species, fertilized eggs develop into females and unfertilized eggs into males. A female stores sperm and can determine the sex of each egg she lays by fertilizing it or leaving it unfertilized. By Fisher's argument, it should still pay a female to produce equal numbers of sons and daughters. Hamilton, noting that the eggs develop within their host—the larva of another insect—and that the newly emerged adult wasps mate immediately and disperse, offered a remarkably cogent analysis. Since only one female usually eggs in a given larva, it would pay her to produce one male only, because this one could fertilize all his sisters on emergence. Like Fisher, Hamilton looked for an evolutionarily stable strategy, but he went a step further in recognizing that he was looking strategy.
What can we know about the scientists Fisher and Hamilton from the passage？
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