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51.
Model-based learning systems such as neural networks usually “forget” learned skills due to incremental learning of new instances. This is because the modification of a parameter interferes with old memories. Therefore, to avoid forgetting, incremental learning processes in these learning systems must include relearning of old instances. The relearning process, however, is time-consuming. We present two types of incremental learning method designed to achieve quick adaptation with low resources. One approach is to use a sleep phase to provide time for learning. The other one involves a “meta-learning module” that acquires learning skills through experience. The system carries out “reactive modification” of parameters not only to memorize new instances, but also to avoid forgetting old memories using a meta-learning module.This work was presented, in part, at the 9th International Symposium on Artificial Life and Robotics, Oita, Japan, January 28–30, 2004 相似文献
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Poly-Si thin-film transistors (TFTs) with channel dimensions (width W , and length L ) comparable to or smaller than the grain size of the poly-Si film were fabricated and characterized. The grain size of the poly-Si film was enhanced by Si ion implantation followed by a low-temperature anneal and was typically 1 to 3 μm in diameter. A remarkable improvement was observed in the device characteristics as the channel dimensions decreased to W =L =2 μm. On the other hand, TFTs with submicrometer channel dimensions were characterized by an extremely abrupt switching in their I D versus V GS characteristics. The improvement was attributed to a reduction in the effect of the grain boundaries and to the effect of the device's floating body 相似文献
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NK Leidy 《Canadian Metallurgical Quarterly》1995,27(1):23-34
The extent to which individuals with a chronic physical illness perform their day-to-day activities and maintain the independence and autonomy they desire is both an indicator of adaptation and an important clinical outcome criterion. Yet the concept of functional performance is not well understood. Studies of people with chronic obstructive pulmonary disease (COPD) have attempted to identify physiologic and psychosocial factors that contribute to functioning in this population. These studies have used a melange of terms, including functional status, functional ability, quality of life, and health status interchangeably. They have also employed a variety of instruments to operationalize functional performance and an assortment of predictors to understand the phenomena. Perhaps as a result of this disarray, no attempt has been made to synthesize the literature for nursing research and practice. The purpose of this paper is to summarize the research on functional performance in people with COPD, indicate areas of understanding and quandary, suggest possible flaws, and propose several new directions for practice and research. 相似文献
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Improving quality of life has always been a goal of rehabilitation medicine. However, health care providers often do not know much about the quality of life of individuals with neuromuscular diseases, nor what factors are critical to achieving a good quality of life. Lack of knowledge about subjective quality of life factors can negatively influence expectations and selection of treatments. In the most glaring cases, a physician's subjective but incorrect assessment of a disabled individuals' quality of life may prevent life-sustaining interventions. As a group, the quality of life of individuals with NMD is not much different than nondisabled controls and is substantially better than presumed by the general public and, often times, by health care workers. Nevertheless, their quality of life is reduced in certain areas. Surprisingly, level of disability is not a critical factor that significantly alters life satisfaction. Presumably, this is because physical functioning has been adequately managed. The greatest problems that individuals with neuromuscular disease identified were: lack of information about the disease and services; poor coordination of services; negative attitudes; and a diminished expectation of their potential. In addition, people with severe disabilities had significant problems obtaining, financing, and managing personal care attendants. Factors related to a good quality of life were related to perceived control, perceived health status, but not disability. The more that people could do for themselves, either on their own or with personal care assistants, assistive devices, and use of technology, the better their quality of life. 相似文献
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The effect of the addition of certain low molecular weight compounds to highly crosslinked epoxy resins was investigated. The behavior which is known as antiplasticization, such as increases in modulus and yield strength and the elimination of β-transition, was observed in the highly crosslinked system as well as in the reported cases of thermoplastics—poly(vinyl chloride), bisphenol A polycarbonate, and polysulfone. Chlorinated biphenyl was found to be one of the most effective antiplasticizers examined in the present paper. However, the remarkable reduction in compressive strain at break and impact strength was not recognized for the highly antiplasticized samples. These phenomena have been interpreted on the basis of free volume concept. 相似文献
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