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物流市场细分的标准有哪些
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Britain’s east midlands were once the picture of English countryside, alive with flocks, shepherds, skylarks and buttercups—the stuff of fairytales. In 1941 George Marsh left school at the age of 14 to work as a herdsman in Nottinghamshire, the East Midlands countryside his parents and grandparents farmed. He recalls skylarks nesting in cereal fields, which when accidentally disturbed would fly singing into the sky. But in his lifetime, Marsh has seen the color and diversity of his native land fade. Farmers used to grow about a ton of wheat per acre; now they grow four tons. Pesticides have killed off the insects upon which skylarks fed, and year-round harvesting has driven the birds from their winter nests. Skylarks are now rare. "Farmers kill anything that affects production," says Marsh. "Agriculture is too efficient." Anecdotal evidence of a looming crisis in biodiversity is now being reinforced by science. In their comprehensive surveys of plants, butterflies and birds over the past 20 to 40 years in Britain, ecologists Jeremy Thomas and Carly Stevens found significant population declines in a third of all native species. Butterflies are the furthest along—71 percent of Britain’s 58 species are shrinking in number, and some, like the large blue and tortoiseshell, are already extinct. In Britain’s grasslands, a key habitat, 20 percent of all animal, plant and insect species are on the path to extinction. There’s hardly a corner of the country’s ecology that isn’t affected by this downward spiral. The problem would be bad enough if it were merely local, but it’s not: because Britain’s temperate ecology is similar to that in so many other parts of the world, it’s the best microcosm scientists have been able to study in detail. Scientists have sounded alarms about species’ extinction in the past, but always specific to a particular animal or place—whales in the 1980s or the Amazonian rain forests in the 1990s. This time, though, the implications are much wider. The Amazon is a "biodiversity hot spot" with a unique ecology. But in Britain, "the main drivers of change are the same processes responsible for species’ declines worldwide," says Thomas. The findings, published in the journal Science, provide the first clear evidence that the world is in the throes of a massive extinction. Thomas and Stevens argue that we are facing a loss of 65 to 95 percent of the world’s species, on the scale of an ice age or the meteorite that may have wiped out the dinosaurs 65 million years ago. If so, this would be only tile sixth time such devastation had occurred in the past 600 million years. The other five were associated with one-off events like the ice ages, a volcanic eruption or a meteor. This time, ecosystems are dying a thousand deaths from overfishing and the razing of the rain forests, but also from advances in agriculture. The British study, for instance, finds that one of the biggest problems is nitrogen pollution. Nitrogen is released when fossil fuels burn in cars and power plants, but also when ecologically rich heath lands are plowed and fertilizers are spread. Nitrogen-rich fertilizers fuel the growth of tall grasses, which in turn overshadow and kill off delicate flowers like harebells and eyebrights. Even seemingly innocuous practices are responsible for vast ecological damage. When British farmers stopped feeding horses and cattle with hay and switched to silage, a kind of preserved short grass, they eliminated a favorite nesting spot of corncrakes, birds known for their raspy nightly mating calls; corncrake populations have fallen 76 percent in the past 20 years, The depressing list goes on and on. Many of these practices are being repeated throughout the world, in one form or another, which is why scientists believe that the British study has global implications. Wildlife is getting blander. "We don’t know which species are essential to the web of life so we’re taking a massive risk by eliminating any of them," says David Wed in, professor of ecology at the University of Nebraska. Chances are we’ll be seeing the results of this experiment before too long. The word "innocuous" in the fifth paragraph probably means
简述物流定价策略的内容。
In 1981 Kenji Urada, a 37-year-old Japanese factory worker, climbed over a safety fence at a Kawasaki plant to carry out some maintenance work on a robot. In his haste, he failed to switch the robot off properly. Unable to sense him, the robot’s powerful hydraulic arm kept on working and accidentally pushed the engineer into a grinding machine. His death made Urada the first recorded victim to die at the hands of a robot. This astounding industrial accident would not have happened in a world in which robot behavior was governed by the Three Laws of Robotics drawn up by Isaac Asimov, a science fiction writer. The laws appeared in I, Robot, a book of short stories published in 1950 that inspired a Hollywood film. But decades later the laws, designed to prevent robots from harming people either through action or inaction, remain in the realm of fiction. With robots now poised to emerge from their industrial cages and to move into homes and workplaces, roboticists are concerned about the safety implications beyond the factory floor. To address these concerns, leading robot experts have come together to try to find ways to prevent robots from harming people. "Security, safety and sex are the big concerns," says Henrik Christensen, chairman of the European Robotics Network at the Swedish Royal Institute of Technology in Stockholm, and one of the organisers of the new roboethics group. Should robots that are strong enough or heavy enough to crush people be allowed into homes Should robotic sex dolls resembling children be legally allowed These questions may seem esoteric but in the next few years they will become increasingly relevant, says Dr. Christensen. According to the United Nations Economic Commission for Europe’s World Robotics Survey, in 2002 the number of domestic and service robots more than tripled, nearly outstripping their industrial counterparts. Japanese industrial firms are racing to build humanoid robots to act as domestic helpers for the elderly, and South Korea has set a goal that 100K of households should have domestic robots by 2020. In light of all this, it is crucial that we start to think about safety and ethical guidelines now, says Dr. Christensen. So what exactly is being done to protect us from these mechanical menaces "Not enough," says Blay Whitby, an artificial-intelligence expert at the University of Sussex in England. This is hardly surprising given that the field of "safety-critical computing" is barely a decade old, he says. But things are changing, and researchers are increasingly taking an interest in trying to make robots safer. One approach, which sounds simple enough, is to try to program them to avoid contact with people altogether. But this is much harder than it sounds. Getting a robot to navigate across a cluttered room is difficult enough without having to take into account what its various limbs or appendages might bump into along the way. Regulating the behavior of robots is going to become more difficult in the future, since they will increasingly have self-learning mechanisms built into them, says Gianmarco Veruggio, a roboticist at the Institute of Intelligent Systems for Automation in Genoa, Italy. As a result, their behavior will become impossible to predict fully, he says, since they will not be behaving in predefined ways but will learn new behavior as they go. It can be inferred from the second paragraph that
I recently took care of a 50-year-old man who had been admitted to the hospital short of breath. During his monthlong stay he was seen by a hematologist, an endocrinologist, a kidney specialist, a podiatrist, two cardiologists, a cardiac electrophysiologist, an infectious-diseases specialist, a pulmonologist, an ear-nose-throat specialist, a urologist, a gastroenterologist, a neurologist, a nutritionist, a general surgeon, a thoracic surgeon and a pain specialist. He underwent 12 procedures, including cardiac catheterization. a pacemaker implant and a bone-marrow biopsy (to work-up chronic anemia). Despite this wearying schedule, he maintained an upbeat manner, walking the corridors daily with assistance to chat with nurses and physician assistants. When he was discharged, follow-up visits were scheduled for him with seven specialists. This man’s case, in which expert consultations sprouted with little rhyme, reason or coordination, reinforced a lesson I have learned many times since entering practice: In our health care system, where doctors are paid piecework for their services, if you have a slew of physicians and a willing patient, almost any sort of terrible excess can occur. Though accurate data is lacking, the overuse of services in health care probably cost hundreds of billions of dollars last year, out of the more than $2 trillion that Americans spent on health. Are we getting our money’s worthy Not according to the usual measures of public health. The United States ranks 45th in life expectancy, behind Bosnia and Jordan, near last, compared with other developed countries, in infant mortality; and in last place, according to the Commonwealth Fund, a health-care research group, among major industrialized countries in health-care quality, access and efficiency. And in the United States, regions that spend the most on health care appear to have higher mortality rates than regions that spend the least, perhaps because of increased hospitalization rates that result in more life-threatening errors and infections. It has been estimated that if the entire country spent the same as the lowest spending regions, the Medicare program alone could save about $40 billion a year. Overutilization is driven by many factors—"defensive" medicine by doctors trying to avoid lawsuits; patients’ demands; a pervading belief among doctors and patients that newer, more expensive technology is better. The most important factor, however, may be the perverse financial incentives of our current system. Overconsultation and overtesting have now become facts of the medical profession. The culture in practice is to grab patients and generate volume. "Medicine has become like everything else," a doctor told me recently. "Everything moves because of money." Consider medical imaging. According to a federal commission, from 1999 to 2004 the growth in the volume of imaging services per Medicare patient far outstripped the growth of all other physician services. In 2004, the cost of imaging services was close to $100 billion, or an average of roughly $350 per person in the United States. Not long ago, I visited a friend—a cardiologist in his late 30s—at his office on Long Island to ask him about imaging in private practices. "When I started in practice, I wanted to do the right thing," he told me matter-of-factly. "A young woman would come in with palpitations. I’d tell her she was fine. But then I realized that she’d just go down the street to another physician and he’d order all the tests anyway: echocardiogram, stress test, Holter monitor—stuff she didn’t really need. Then she’d go around and tell her friends what a great doctor— a thorough doctor—the other cardiologist was. "I tried to practice ethical medicine, but it didn’t help. It didn’t pay, both from a financial and a reputation standpoint." Last year, Congress approved steep reductions in Medicare payments for certain imaging services. Deeper cuts will almost certainly be forthcoming. This is good; unnecessary imaging is almost certainly taking place, leading to false-positive results, unnecessary invasive procedures, more complications and so on. But the problem in medicine today is much larger than imaging. Doctors are doing too much testing and too many procedures, often for the sake of business. And patients, unfortunately, are paying the price. "The hospital is a great place to be when you are sick," a hospital executive told me recently. "But I don’t want my mother in here five minutes longer than she needs to be.\ According to the author, which statement is NOT true
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