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71.
We introduce in this paper a new multiple-objective linear programming (MOLP) algorithm. The algorithm is based on the single-objective path-following primal—dual linear programming algorithm and combines it with aspiration levels and the use of achievement scalarizing functions. The resulting algorithm falls in the class of interactive MOLP algorithms, as it requires interaction with the decision maker (DM) during the iterative process to obtain statements of aspirations for levels of objectives of the MOLP problem. The interior point algorithm is then used to trace a path of interates from a current (interior) solution and approach as closely as desired a non-dominated solution corresponding to the optimum of the achievement scalarizing function. The timing of the interaction with the DM is dependent on the progress of the interior algorithm. It can take place every few, pre-specified, iterations or after the duality gap achieved for the stated aspirations has fallen below a certain threshold. It is expected that an interior algorithm will speed up the overall process of searching and finding the most preferred MOLP solution—especially in large-scale problems—by avoiding the need for numerous pivot operations and their corresponding interactive sessions inherent in simplex-based algorithms.  相似文献   
72.
A huge set of focused attention experiments show that when presented with color words printed in color, observers report the ink color faster if the carrier word is the name of the color rather than the name of an alternative color, the Stroop effect. There is also a large number (although not so numerous as the Stroop task) of so-called “redundant targets studies” that are based on divided attention instructions. These almost always indicate that observers report the presence of a visual target (‘redness’ in the stimulus) faster if there are two replications of the target (the word RED in red ink color) than if only one is present (RED in green or GREEN in red). The present set of four experiments employs the same stimuli and same participants in both designs. Evidence supports the traditional interference account of the Stroop effect, but also supports a non-interference parallel processing account of the word and the color in the divided attention task. Theorists are challenged to find a unifying model that parsimoniously explains both seemingly contradictory results.  相似文献   
73.
因中国传统伦理文化对人们意识观念的深刻影响导致中国脑死亡立法步履艰难。从中国传统文化视角分析中国的脑死亡及相关伦理问题,提出中国脑死亡诊断标准的制定必须充分考虑民族心理感受,要立足于民族文化理性地探索“中国脑死亡”。  相似文献   
74.
博物学是指关于现实生活中具体物质世界的综合实用知识。在对中医药学的科学性评价中,有学者从博物学传统的回归入手加以论述,但科学从来不是静止不动的,而是不断向前发展的,博物学毕竟是前科学时代的产物,它的性质如何,它能给中医药学带来什么,这都是需要正确审视的.  相似文献   
75.
Participation in risky sexual behaviors has many deleterious consequences and is a source of concern for parents as well as practitioners, researchers, and public policy makers. Past research has examined the effect of family structure and supportive parenting on risky sexual behaviors among emerging adults. In the present study, we attempt to identify the mediators that explain this relationship. Using survey data from a sample of over 2,000 college students (1,297 females and 780 males) we use structural equation modeling to investigate the role of commitment to marriage, desired characteristics in an intimate partner, and sociosexuality in linking the influence of family structure and supportive parenting to risky sexual behaviors. Results indicate that respondents from continuously married families were more committed to marriage, and this commitment reduced the probability of risky sexual behavior both directly, as well as indirectly through its negative impact on unrestricted sociosexuality. On the other hand, respondents who reported having supportive parents rated sensitivity and similarity of values as more important in a mate than physical attractiveness and sexual compatibility. This approach to mate selection reduces unrestricted sociosexuality and, in turn, risky sexual behavior. Even after taking our mediators into account, there is still a direct effect of family factors on risky sexual behavior. Gender differences in the pattern of findings are discussed and directions for future research are identified.  相似文献   
76.
卫生改革需要有包括卫生改革伦理学理念在内的全方位改革理念的联手支撑。伦理含金量缺失或者不足,卫生改革实践就难以取得圆满成功。因此,目前展开的新一轮卫生改革,必须以“效率与公平合理兼顾”为核心准则,在完善政策、规划目标、组织实施等全过程中切实保证卫生改革伦理学理念准确到位和正常运作。  相似文献   
77.
In a sample of 976 consecutive cases derived from the recent world-wide Field Trial of Autism and other Pervasive Developmental Disorders, we tested the accuracy of the 15 ICD-10 criteria for the diagnosis of Autism, by comparing neural network models (NN) to more conventional multivariate competitors, namely, linear and quadratic discriminant function analyses and logistic regression. NNs were less accurate than competitors, both in terms of cross-validation results as well as in levels of shrinkage from training to test conditions. The clinical research implications of these results are discussed.  相似文献   
78.
关于艾滋病病毒发现权之争的著述在国外已有许多,但国内对这一事件从科学史角度的研究还不多见.本研究试图在艾滋病的最初发现,病源学研究,以及病毒发现之争的起因等方面进行回顾的基础上,对美国科学家和美国政府在这一事件中的一些做法和表现,从美国当代国家科学发展战略观的角度进行解读,并通过历史分析求得有益的启示.  相似文献   
79.
Loneliness is a universal social phenomenon often producing debilitating effects on many aspects of human functioning. The present study compared the qualitative aspects of loneliness in two terminally ill samples to that of a more healthy sample. 329 multiple sclerosis and 315 cancer patients, as well as 391 nonrandom healthy participants answered a 30-item questionnaire on loneliness. Analysis indicated the experience of loneliness which characterizes multiple sclerosis and cancer patients differs from that of the more healthy group.  相似文献   
80.
Systems factorial technology (SFT) is a theory-driven set of methodologies oriented toward identification of basic mechanisms, such as parallel versus serial processing, of perception and cognition. Studies employing SFT in visual search with small display sizes have repeatedly shown decisive evidence for parallel processing. The first strong evidence for serial processing was recently found in short-term memory search, using target-distractor (T-D) similarity as a key experimental variable (Townsend & Fifi?, 2004). One of the major goals of the present study was to employ T-D similarity in visual search to learn whether this mode of manipulating processing speed would affect the parallel versus serial issue in that domain. The result was a surprising and regular departure from ordinary parallel or serial processing. The most plausible account at present relies on the notion of positively interacting parallel channels.  相似文献   
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