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991.
In this article the perspective shifts to the “upstream” end of the agricultural knowledge and information system (AKIS). Because knowledge policy and strategic decision-making are not the prerogative of the public sector, organizations such as cooperative unions and multinational companies are included. After considering the influence of the changing environment on the nature of the AKIS, the role of knowledge management and policy in the emerging knowledge and information market is examined. Special attention is given to public and private R&D. The article then looks where information technology (IT) fits in and what considerations determine strategic investment in IT projects and sustained services. Some of the European experiences with this strategic investment are evaluated.  相似文献   
992.
993.
994.
Depression in some patients with spinal cord injuries may be clinically significant and, when present, should be treated to decrease morbidity including decreased physical functioning. Depression associated with spinal cord injury (SCI) may be misevaluated, due to (1) nonspecific multifactorial production of depression symptoms and (2) SCI-specific decrease in somatic sensory central nervous system input. The Somatic Suppression Hypothesis suggests that SCI patients have difficulty experiencing any intense emotion because of suppression of physiological arousal. In addition, cognitive processes that may reduce depression in SCI patients include: (1) attribution of somatic symptoms of depression to medical (biological) causes, (2) realistic, positive expectations for physical improvement, and (3) the perception that the disability of the SCI is only minimally related to the patient’s self-care after complete evaluation. Health personnel should accept lack of depression in SCI, and should encourage positive realistic expectations of recovery.  相似文献   
995.
比较不同智商正常儿童和唐氏综合症(Down’s Syndrome)儿童的关联性负变(Contingent Negative Variation CNV)。结果是:智力缺陷儿童的CNV幅度明显下降甚至缺失。智力较高儿童CNV较大,CNV的晚成分与智商,尤其是言语智商密切相关,智商和言语智商越高,晚成分幅度越大。似乎晚成分更能反映人的语言方面的能力。早成分则与语言、操作以及全量表智商都无明显关系。  相似文献   
996.
人类颜色视觉的计算理论   总被引:2,自引:0,他引:2  
该文有机地结合了计算视觉理论和生态学视觉理论,指出颜色信息处理的根本任务是检测环境中的光不变量。在此基础上,作者提出了颜色视觉的计算理论以及计算理论本身的生物学标准。初级视觉计算是典型的不适定问题,动物的视觉系统则利用视环境中存在的条件将该不适定问题转化为定解问题。本文引入颜色视觉计算的免要条件,客观性约束,以及颜色认知的神经表象,证明了上述约束下颜色算法的存在性。本文给出了构造颜色知觉的基本假设。同时,该文还讨论了与上述问题密切相关的几个基本问题:神经表象的完备性,主观色觉的客观性,明度知觉和颜色知觉的统一,人类主观色觉的实现方式。  相似文献   
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998.
Behavior analysis is a cultural system of which the Association for Behavior Analysis is a component cultural system. As cultural systems, they are composed of interlocking behavioral contingencies that constitute their cultural practices. Critical to the survival of both cultural systems is the frequency of interaction with and the nature of the content of the behavioral contingencies composing those cultural practices. The strengths of behavior analysis as a cultural system include its disciplinary character and its worldwide community of scientists and practitioners; its ability to be integrated into a scientific worldview; its track record in providing effective solutions to problems of importance to society; and the high levels of intellect, competence, and commitment that are characteristic of its participants. Weaknesses of behavior analysis are its status as an academic orphan, its relatively small size and its underdeveloped professional identity, and a lack of sociopolitical sophistication among many of its members. Behavior analysis will need to maximize its strengths and mitigate its weaknesses if it is to take advantage of the many opportunities available for growth in the modern world.  相似文献   
999.
1000.
Content-oriented test development requires information derived from a comprehensive job analysis. The job data typically consist of task and skill statements identified by subject matter experts. These statements characterize a target job and are then used to develop the test plan and item budget. The predominant practice for combining data from the task and job skill domains to facilitate preparation of a test plan and item budget is an impressionistic approach. This study reports variations and extensions of an alternative quantitative procedure for linking task and job skill data (Hughes & Prien, 1989) using results obtained in field studies. The results indicate that the procedure reported by Hughes and Prien (1989) yields consistent results. Also, modifications to the procedure result in more detailed solutions.Dr. Charles Lawshe graciously contributed three sets of job analysis data to this research project. Dr. Lawshe also provided a very thoughtful and cogent critique of our attempts to express these thoughts to a user audience and for this we are grateful.  相似文献   
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