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101.
Researchers often have expectations about the research outcomes in regard to inequality constraints between, e.g., group means. Consider the example of researchers who investigated the effects of inducing a negative emotional state in aggressive boys. It was expected that highly aggressive boys would, on average, score higher on aggressive responses toward other peers than moderately aggressive boys, who would in turn score higher than nonaggressive boys. In most cases, null hypothesis testing is used to evaluate such hypotheses. We show, however, that hypotheses formulated using inequality constraints between the group means are generally not evaluated properly. The wrong hypotheses are tested, i.e.. the null hypothesis that group means are equal. In this article, we propose an innovative solution to these above-mentioned issues using Bayesian model selection, which we illustrate using a case study. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
102.
The current study examined a prediction derived from the challenge hypothesis; individuals who viciously win a competition of rank order will seek out pornography relatively more often than individuals who viciously lose a competition. By examining Google keyword searches during the 2006 and 2010 midterm elections in the United States, the relative popularity of various pornography keyword searches was computed for each state and the District of Columbia the week after each midterm election. Consistent with previous research examining presidential elections and the challenge hypothesis, individuals located in traditionally Republican states tended to search for pornography keywords relatively more often after the 2010 midterm election (a Republican victory) than after the 2006 midterm election (a Democratic victory). Conversely, individuals located in traditionally Democratic states tended to search for pornography relatively less often following the 2010 midterm election than they did following the 2006 midterm election.  相似文献   
103.
本文从四个方面揭示了马克思主义假说观的基本内容,阐明了马克思主义的假说观是唯物辩证的假说观,强调了实践对于假说的决定作用,指出了假说在认识中的重要作用,最后提出假说在哲学社会科学中具有普遍意义。  相似文献   
104.
S. M. Monroe and K. L. Harkness (see record 2005-02750-005) reviewed the empirical evidence supporting R. M. Post's (see record 1992-43211-001) kindling model, which suggests the 1st episode of depression is more likely to be preceded by major stressors than are subsequent episodes. Their review highlighted the diverse interpretations of Post's premise in the current literature and the changes in research methods that have contributed to this interpretive shift. The authors conducted a meta-analysis (N=13 studies) to test Post's premise that integrated early and recent research and examined potential moderators. A proportion difference effect size was used. Results indicated that 1st onsets of depression were more likely than recurrences to be preceded by severe life events, supporting Post's premise. The moderator analyses suggested that support may be most evident in patient samples and may vary according to age and gender, with less support for Post's premise evidenced in younger samples and in women. Although these results are preliminary, as the analysis included a small number of studies, they suggest that future research should further examine factors that influence the stress-depression relationship with successive recurrences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
105.
When participants search for a target letter while reading, they make more omissions if the target letter is embedded in frequently used words or in the most frequent meaning of a polysemic word. According to the processing time hypothesis, this occurs because familiar words and meanings are identified faster, leaving less time for letter identification. Contrary to the predictions of the processing time hypothesis, with a rapid serial visual presentation procedure, participants were slower at detecting target letters for more frequent words or the most frequent meaning of a word (Experiments 1 and 2) or at detecting the word itself instead of a target letter (Experiment 3). In Experiments 4 and 5, participants self-initiated the presentation of each word, and the same pattern of results was observed as in Experiments 1 and 3. Positive correlations were also found between omission rate and response latencies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
106.
Previous research suggests that older adults derive interpretations of unfamiliar words that are less precise than those of young adults (D. McGinnis & E. M. Zelinski, 2000). Thirty-one adults aged 18-37, 27 aged 65-74, and 28 aged 75-87 read passages containing unfamiliar words (1 per passage) and were asked to think aloud during reading. After reading each passage, participants selected meaning-relevant cues and rated the quality of 4 definition options. Compared with the 2 younger groups, the oldest group rated thematic and irrelevant definitions significantly higher, and their think-aloud protocols included more generalized inferences. Results pertaining to cue selection were not significant. Taken together, these results suggest that age differences in meaning derivation may be related to inferential processing that is overgeneralized, providing support for the abstraction-deficit hypothesis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
107.
We consider a measure of the diversity of a population based on the λ-measure of hypoentropy introduced by Ferreri (1980). Our purpose is to study its asymptotic distribution for testing hypotheses. A numerical example based on real data is given. This work was partially supported by the Dirección General de Investigación Cientifica y Técnica (DGICYT) under the contract PS89-0019.  相似文献   
108.
The contact hypothesis proposes that interaction between members of different groups reduces intergroup prejudice if--and only if--certain optimal conditions are present. For over 50 years, research using this framework has explored the boundary conditions for ideal contact and has guided interventions to promote desegregation. Although supporting the contact hypothesis in principle, the authors critique some research practices that have come to dominate the field: (a) the prioritizing of the study of interactions occurring under rarefied conditions, (b) the reformulation of lay understandings of contact in terms of a generic typology of ideal dimensions, and (c) the use of shifts in personal prejudice as the primary measure of outcome. The authors argue that these practices have limited the contact hypothesis both as an explanation of the intergroup dynamics of desegregation and as a framework for promoting social psychological change. In so arguing, the authors look toward a complementary program of research on contact and desegregation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
109.
多轴应力状态下脆性材料强度的估算   总被引:5,自引:2,他引:3  
用椭圆盘扁平裂纹模型模拟材料中的缺陷,根据统计断裂理论推导出了任意应力状态下脆性材料的破坏概率和期望强度的计算式,从而为从简单应力状态下测得的材料强度去预测其他应力状态下该材料的强度提供了一种基本方法。  相似文献   
110.
Comments on the article by J. S. Hyde (see record 2005-11115-001), which reviewed the results of 46 meta-analyses of studies investigating gender differences and produced results that supported the gender similarities hypothesis that men and women are similar along most psychological traits. The current authors agree with the gender similarities hypothesis but argue here that Hyde's review has limitations that caused it to underestimate the true extent of gender differences. They also outline the benefits of adopting an evolutionary psychological perspective on gender differences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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