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881.
882.
This study explores how undergraduates seek information across various information structures. Taking part in an interview, fifteen students of diverse backgrounds described their information seeking. The findings pointed to several issues relating to the underlying structures of information resources. Suggestions are made for structural improvements to facilitate undergraduates’ information seeking.  相似文献   
883.
提出了一种用于设备性能退化评估的PCA-CMAC(主成分分析-小脑模型节点控制器)模型.该模型利用PCA进行特征提取,去除多个传感器信号特征的冗余信息,并且减少CMAC的输入维数;利用CMAC的局部泛化能力定量地评估设备的性能退化.给出了模型的实现过程,并将模型应用于钻削过程刀具状态的评估,试验结果证明该模型能基于刀具的正常状态,对刀具的磨损状态进行定量的评估.分析了CMAC中泛化参数g和量化参数r对评估结果的影响,g越大,CMAC的泛化能力越好,但各退化状态之间的区别越不明显;r越小,各退化状态之间越容易区分,但所需的权存储空间越大.2个参数的基本选择原则是CMAC的权存储空间应尽量小,与此同时,各退化状态之间应容易区分.  相似文献   
884.
One hundred forty-four 10th-grade students received training on one of three processing methods: coding-mapping (simultaneous), coding only, or decision tree (sequential). Then they learned a biconditional rule under one of eight transfer test conditions based on a 2 (paradigm: rule vs complete learning) × 2 (memory aids: 0 vs 4) × 2 (focus instance: presence vs absence) design. Although the coding-mapping students processed concept instances in much the same way as the coding-only students, they acquired the target rule more frequently, and they processed instances more quickly and more consistently than the decision-tree students. The observed ordinality of the responses of four truth-table classes was found to be more consistent with the simultaneity than with the sequentiality hypothesis. As expected, training interacted with paradigm and also with memory aids and focus instance. The induced simultaneous processing strategy apparently works optimally under rule learning, while the sequential strategy is difficult to induce and/or not optimal for rule-learning operations.  相似文献   
885.
The need of after-school programs has become urgent for school-age children in many industrialized countries due to social structure changes. This research develops a hierarchical framework to evaluate after-school programs from two distinct aspects??service quality from parents?? perspectives and marketing strategy from operators?? perspectives??each aspect respectively associated with five mutually independent criteria. Two different questionnaire surveys are conducted respectively to parents and providers in Hsinchu, Taiwan based on pairwise comparison on Saaty??s nine-point scale. Fuzzy analytic hierarchy process is then employed to calculate the relative importance of the criteria under each aspect. The results show that the top three concerns from parents?? perspectives are communication and attentiveness, teacher qualification and counseling, and fee and location, whereas the top three concerns from operators?? perspectives are promotion, price, and product. Our findings reveal a consistency between the concerns of parents and of operators, but the important rankings from the two perspectives are not exactly the same, implying that the parents and the operators do have somewhat different viewpoints in evaluating the after-school programs.  相似文献   
886.
887.
    
Science performance is determined, to a large extent, by what students already know about science (i.e., science knowledge) and what techniques or methods students use in performing science tasks (i.e., cognitive strategies). This study describes and compares science knowledge, science vocabulary, and cognitive strategy use among four diverse groups of elementary students: (a) monolingual English Caucasian, (b) African-American, (c) bilingual Spanish, and (d) bilingual Haitian Creole. To facilitate science performance in culturally and linguistically congruent settings, the study included student dyads and teachers of the same language, culture, and gender. Science performance was observed using three science tasks: weather phenomena, simple machines, and buoyancy. Data analysis involved a range of qualitative methods focusing on major themes and patterns, and quantitative methods using coding systems to summarize frequencies and total scores. The findings reveal distinct patterns of science knowledge, science vocabulary, and cognitive strategy use among the four language and culture groups. The findings also indicate relationships among science knowledge, science vocabulary, and cognitive strategy use. These findings raise important issues about science instruction for culturally and linguistically diverse groups of students.  相似文献   
888.
Portents of the demise of the Professional Doctorate have emerged in some recent policy and institutional circles in Australia, raising questions about the meaning and relevance of the Professional Doctorate in an era of ‘league tables’ and research assessment in Australia. This article argues that such portents, based largely on narrow market‐driven arguments, are premature, reactive and unhelpful, in that they foreclose on a set of critical questions concerning the future purpose, scope and practice of doctoral education. The article argues that the simple re‐assertion of the PhD as the default award represents a restoration of the logics and imperatives of disciplinarity and of older notions of so‐called ‘real’ research. Further, questions of the changing economies of knowledge and practice within, between and beyond the reach of the university, are subordinated and disavowed. The article presents a re‐reading of the emergence of Professional Doctorates, from the perspective of a decade‐and‐a‐half of development and change. It suggests the need to revisit that history critically in the light of the current developments in doctoral education, in knowledge production and in developing different relations around knowledge between universities and different social and professional domains. Such revisitings can bring out emerging issues for doctoral education at a time when anxieties may inhibit taking up opportunities for innovation and linking with new kinds of knowledge production that go beyond Euro‐centric and university‐centric traditions.  相似文献   
889.
ABSTRACT

Seasoned geriatric community health workers offered valuable data that will inform educators and community health workers working with older persons. Geriatric community health workers’ views about retirement and about facilitators and barriers that keep them engaged with older adults during retirement were identified. Twenty geriatric community health workers participated in semi-structured, qualitative interviews conducted by the research team. Sixty percent of the participants (N = 12) reported plans not to work during retirement, although 40% (N = 8) expressed interest in full- or part-time employment post-retirement. When asked about their expectations to stay in the field of aging or gerontology in some capacity during retirement, 30% (N = 6) expected to stay in gerontology during retirement. The findings from this research will help organizations and educational institutions create programs and resources that will encourage geriatric community health workers to continue working in the field of aging during retirement.  相似文献   
890.
    
Consumption of food pellets was examined in four water-deprived rats during 1-h sessions in which water was presented once every 30, 60, or 120 sec independently of the rats’ behavior according to three fixed-time (FT) schedules. Correlated with each FT condition was a continuous reinforcement (CRF) control condition in which the rats received, at the start of the session, the number of dipper presentations that were programmed to occur during the corresponding FT condition. During both the FT and CRF conditions, pellets per dipper presentation decreased and food intake rate increased with rate of water presentation, and there was a direct linear relation between log food intake and log water intake. For each of these three measures there was less eating under the FT condition than under the CRF condition, but the difference between the FT and CRF functions decreased at shorter FT values. These data are discussed in terms of the effects of amount of water on food consumption and the principle of temporal summation.  相似文献   
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