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Conclusion In the guise of ABB Daimler-Benz Transportation and Siemens, Germany has two powerful systems suppliers in a good position to keep pace with other systems suppliers on global markets. As in the air-travel industry it is conceivable that developments are moving towards a uniform rail technology. Although the buy national principle still dominates procurement practices, and national egos still dominate the development of rail systems (ICE, TGV), growing competition from Japan could force Europe to develop a European system. This would significantly increase the chances of European industry in bidding for international contracts. For this reason the EU should not relent in its efforts to standardise European rail systems.  相似文献   
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Transient ischemic attack (TIA) is defined as "an episode of focal loss of brain function attributed to ischemia that lasts less than 24 hours, is localized to a portion of the brain supplied by one vascular system, has no persistent deficit, and is not attributable to any other cause." Most TIAs are caused by small thromboemboli that originate in atheromatous areas in neck vessels or the heart. Other mechanisms include nonatherosclerotic vascular diseases, mitral valve prolapse, hematologic diseases, and abnormal blood pressure fluctuations. Even in series of fully investigated cases, there remains a group in which no cause can be found. The great majority of TIAs are extremely brief. In one series, 24% ended within 5 minutes, 39% in 15 minutes, 50% in 30 minutes, and 60% in 1 hour.  相似文献   
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Hypertrophic Cardiomyopathy (HC) is portrayed in past literature as having an ominous prognosis. However, most studies emanated from medical centers and suffered from potential referral bias. A population based, community diagnosed and treated survival study is analyzed by the life table method. Despite potential causes for both underestimation of the observed mortality as well as for overestimation of expected mortality, the study appears to reveal a more favorable prognosis for HC in this population.  相似文献   
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Spark innovation through empathic design   总被引:11,自引:0,他引:11  
Companies are used to bringing in customers to participate in focus groups, usability laboratories, and market research surveys in order to help in the development of new products and services. And for improving products that customers know well, those tools are highly sophisticated. For example, knowledgeable customers are adept at identifying the specific scent of leather they expect in a luxury vehicle or at helping to tune the sound of a motorcycle engine to just the timbre that evokes feelings of power. But to go beyond improvements to the familiar, companies need to identify and meet needs that customers may not yet recognize. To accomplish that task, a set of techniques called empathic design can help. Rather than bring the customers to the company, empathic design calls for company representatives to watch customers using products and services in the context of their own environments. By doing so, managers can often identify unexpected uses for their products, just as the product manager of a cooking oil did when he observed a neighbor spraying the oil on the blades of a lawn mower to reduce grass buildup. They can also uncover problems that customers don't mention in surveys, as the president of Nissan Design did when he watched a couple struggling to remove the backseat of a competitor's minivan in order to transport a couch. The five-step process Dorothy Leonard and Jeffrey Rayport describe in detail is a relatively low-cost, low-risk way to identify customer needs, and it has the potential to redirect a company's existing technological capabilities toward entirely new businesses.  相似文献   
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Poverty,population and environmental degradation in China   总被引:7,自引:0,他引:7  
Rozelle S  Huang J  Zhang L 《Food Policy》1997,22(3):229-251
This article examines the relationship between poverty, population, and environmental degradation in China. Environmental conditions include water pollution, deforestation, destruction of grasslands, soil erosion, and salinization. The authors review China's success in controlling environmental degradation through leadership, environmental policies, and institutional capacity. Findings suggest that environmental progress is best achieved indirectly by poverty alleviation, market integration, and population control. Government policies were not very effective. Degradation occurs due to limited financial resources, poorly trained personnel, and political factors. Control of water pollution was instituted since the 1980s. The levels of pollutants have been reduced, but the type of pollutant determines the seriousness of impact. Water pollution is due to industrial wastes, agricultural run-off, and soil erosion. Since the 1970s, reforestation targets have not been met. Technical extension and monitoring of planting is not available in most areas, and private, profit seeking interests control acreage. Grassland destruction is due to deforestation, agricultural expansion, and overgrazing. Independent regional authorities have successfully managed pasture programs. Erosion is the most serious in Loess Plateau, the Red Soils area, the Northeast China Plain, and the Northwest Grasslands, which comprise 70% of total land area. In 1990, erosion control was practiced in 39% of eroded land area. Salinization has remained fairly constant. Environmental controls (direct regulation, planned recovery, and state-mandated technological improvements) are uneven. The main tool for environmental management is the State Environmental Protection Commission and its executive unit, SEPA. Problems stem from vague laws, lack of means of enforcement, lack of coordination of laws, and lack of standards, schedules, and other provisions in ordinances.  相似文献   
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