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81.
It was hypothesized that the proportion of interrupted tasks recalled would be greatest among volunteers serving by choice and least among draftees not willing to volunteer, with draftees who had been willing to volunteer falling between the 2. Within each of these 3 groups those given task orienting instructions were expected to recall greater proportions of interrupted tasks than those given ego orienting instructions. College students divided into 6 groups of 16 Ss each in a 3 X 2 factorial design were tested individually using the standard Zeigarnik procedure. The results conformed to expectations although the differences among the volunteering groups were small. It was argued that differences in degree of task involvement and ego involvement account for these results. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
82.
Experimental evaluation of hotspot identification methods   总被引:1,自引:0,他引:1  
Identifying crash "hotspots", "blackspots", "sites with promise", or "high risk" locations is standard practice in departments of transportation throughout the US. The literature is replete with the development and discussion of statistical methods for hotspot identification (HSID). Theoretical derivations and empirical studies have been used to weigh the benefits of various HSID methods; however, a small number of studies have used controlled experiments to systematically assess various methods. Using experimentally derived simulated data--which are argued to be superior to empirical data, three hot spot identification methods observed in practice are evaluated: simple ranking, confidence interval, and Empirical Bayes. Using simulated data, sites with promise are known a priori, in contrast to empirical data where high risk sites are not known for certain. To conduct the evaluation, properties of observed crash data are used to generate simulated crash frequency distributions at hypothetical sites. A variety of factors is manipulated to simulate a host of 'real world' conditions. Various levels of confidence are explored, and false positives (identifying a safe site as high risk) and false negatives (identifying a high risk site as safe) are compared across methods. Finally, the effects of crash history duration in the three HSID approaches are assessed. The results illustrate that the Empirical Bayes technique significantly outperforms ranking and confidence interval techniques (with certain caveats). As found by others, false positives and negatives are inversely related. Three years of crash history appears, in general, to provide an appropriate crash history duration.  相似文献   
83.
Reports an error in the original article by Shirom (Journal of Applied Psychology. Vol 67(1) Feb 1982, 45-52). a percentage was incorrectly reported. On page 45, the fourth line from the bottom of the abstract, the value 21% should read 12%. In addition, one of the values in Table 2 (page 50) was incorrectly labeled significant. The asterisk for the value .21 (the adjusted mean for R2) should be deleted. (The following abstract of this article originally appeared in record 1982-10870-001.) Management perceptions of advantageous settlements of strikes were predicted by the extent to which the struck plant was kept in operation, the extent to which a mediator was involved, frequency of strikes in the plant in the past, duration of the strike and its breadth. Data from 51 chief management negotiators show that past frequency, duration, and a mediator's involvement were not significant as predictors. The management's perception of strike settlement as advantageous was found to be positively affected either by large breadth of the strike or by the management's success in keeping the plant in operation during the strike. Results indicate that management's power to resist strikes by operating the struck plant is a significant predictor. Findings cast doubt on the notion that unions are successful in identifying as strike targets employers who are vulnerable to the costs imposed by a strike. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
84.
A self-report questionnaire dealing with food preferences (Food Preference Inventory—FPI) was proposed as a measure of Ss' contemporaneous position in respect to oral-passive vs. oral-sadistic involvement. The measure was pretested and through an item analysis found to be internally consistent enough to be utilized. The questionnaire was expanded and retested on new Ss to guarantee its stability and to increase its discriminatory potential. Finally it was subjected to validation by contrasting the scores of a group of Ss thought to be high on oral passivity (alcoholics) vs. a normal control group and by correlating it with their orality trait scores. The FPI was found to be fairly reliable and yielded data in agreement with the 2 validation predictions. It was concluded that food preferences as measured by the inventory offer a valid means of assessing an individual's position in regard to orality. (19 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
85.
Efficient algorithms for optimistic crash recovery   总被引:1,自引:0,他引:1  
Summary Recovery from transient processor failures can be achieved by using optimistic message logging and checkpointing. The faulty processorsroll back, and some/all of the non-faulty processors also may have to roll back. This paper formulates the rollback problem as a closure problem. A centralized closure algorithm is presented together with two efficient distributed implementations. Several related problems are also considered and distributed algorithms are presented for solving them. S. Venkatesan received the B. Tech. and M. Tech degrees from the Indian Institute of Technology, Madras in 1981 and 1983, respectively and the M.S. and Ph.D. degrees in Computer Science from the University of Pittsburgh in 1985 and 1988. He joined the University of Texas at Dallas in January 1989, where he is currently an Assistant Professor of Computer Science. His research interests are in fault-tolerant distributed systems, distributed algorithms, testing and debugging distributed programs, fault-tolerant telecommunication networks, and mobile computing. Tony Tony-Ying Juang is an Associate Professor of Computer Science at the Chung-Hwa Polytechnic Institute. He received the B.S. degree in Naval Architecture from the National Taiwan University in 1983 and his M.S. and Ph.D. degrees in Computer Science from the University of Texas at Dallas in 1989 and 1992, respectively. His research interests include distributed algorithms, fault-tolerant distributed computing, distributed operating systems and computer communications.This research was supported in part by NSF under Grant No. CCR-9110177 and by the Texas Advanced Technology Program under Grant No. 9741-036  相似文献   
86.
ContextFor more than four decades it has been intuitively accepted that user involvement (UI) during system development lifecycle leads to system success. However when the researchers have evaluated the user involvement and system success (UI-SS) relationship empirically, the results were not always positive.ObjectiveOur objective was to explore the UI-SS relationship by synthesizing the results of all the studies that have empirically investigated this complex phenomenon.MethodWe performed a Systematic Literature Review (SLR) following the steps provided in the guidelines of Evidence Based Software Engineering. From the resulting studies we extracted data to answer our 9 research questions related to the UI-SS relationship, identification of users, perspectives of UI, benefits, problems and challenges of UI, degree and level of UI, relevance of stages of software development lifecycle (SDLC) and the research method employed on the UI-SS relationship.ResultsOur systematic review resulted in selecting 87 empirical studies published during the period 1980–2012. Among 87 studies reviewed, 52 reported that UI positively contributes to system success, 12 suggested a negative contribution and 23 were uncertain. The UI-SS relationship is neither direct nor binary, and there are various confounding factors that play their role. The identification of users, their degree/level of involvement, stage of SDLC for UI, and choice of research method have been claimed to have impact on the UI-SS relationship. However, there is not sufficient empirical evidence available to support these claims.ConclusionOur results have revealed that UI does contribute positively to system success. But it is a double edged sword and if not managed carefully it may cause more problems than benefits. Based on the analysis of 87 studies, we were able to identify factors for effective management of UI alluding to the causes for inconsistency in the results of published literature.  相似文献   
87.
The continuous spread of the COVID-19 pandemic is causing people to feel anxiety and stress. This study constructs a four-layer research model to examine how a 360° virtual tour can reduce people's psychological stress through two types of presence (the sense of presence and telepresence) and affective-motivational states (enjoyment and involvement) in this extraordinary period of the COVID-19 pandemic. In order to test the moderating effect of involvement, partial least squares (PLS) analysis is employed to analyse valid data collected from 235 individuals. The results of this study indicate that telepresence has a higher impact in generating affective-motivational states than the sense of presence. Among the factors, enjoyment shows the highest effect on satisfaction with the 360° virtual tour experience and stress reduction; involvement moderates the effect of telepresence on satisfaction with the 360° virtual tour experience. This study also contributes to virtual reality research by distinguishing the concepts of ‘sense of presence’ and ‘telepresence’ as well as demonstrating the mechanisms whereby virtual reality technology influences people's psychological well-being. Timely recommendations are provided for people in order to reduce psychological stress during and after COVID-19 pandemic.  相似文献   
88.
车辆典型薄壁梁碰撞仿真中接触摩擦问题的研究   总被引:5,自引:0,他引:5  
对车辆碰撞中对碰撞能量吸收起重要作用的典型截面的薄壁梁进行了碰撞性能的有限元仿真,并与试验结果进行了比较,验证了模型的准确性。然后用此有限元模型对碰撞仿真中的接触摩擦问题进行了研究,提出了接触摩擦系数选取的一般性建议。  相似文献   
89.
张宇霞  周明辉  张伟  赵海燕  金芝 《软件学报》2017,28(6):1343-1356
2000年以来,开源软件取得了显著进展,展示出一种以用户创新为驱动且低成本高质量的新型软件开发方式.越来越多的商业组织参与到开源项目中,期望利用开源软件及其优势实现自身的商业目标.由于开源软件开发方式与传统的软件工程方法存在显著差异,为了加入开源社区,商业组织必须要对自身原有的软件开发方式、业务模式等做出调整.在这种情况下,一个亟待解决的问题是商业组织应当采取怎样的参与模式才能有效融入开源社区.为此,本文进行了如下三个方面的研究:1.采用雪球采样方法对OpenStack相关的文本数据进行收集,为定性分析提供数据基础;2.借鉴扎根理论,通过对所收集数据的过滤和归纳,总结出不同商业组织参与OpenStack的模式;3.在此基础上,提炼出四种更具一般性的参与模式,为商业组织参与开源项目提供经验参考与决策支持.  相似文献   
90.
Many studies have examined the construct validity of the criticism component of expressed emotion, but little work has been done on clarifying the emotional overinvolvement (EOI) construct. In a sample of 115 recently episodic patients with bipolar disorder, the authors of the present study examined the construct validity of an observational coding system for both appropriate and inappropriate emotional involvement that permitted separate ratings for relatives' intrusiveness, self-sacrificing behaviors, and distress related to the patient's well-being. Findings support the measure's reliability and convergent validity and are moderately supportive of the measure's discriminant validity. Results also suggest that Camberwell Family Interview (C. E. Vaughn & J. P. Leff, 1976) EOI ratings do not discriminate among the different dimensions of the emotional involvement construct (or their appropriateness or inappropriateness) as revealed in laboratory-based interactions. The findings suggest that clinicians working with such families might consider differentiating among the various ways in which family members are involved with the patient and helping them learn to judge under what circumstances such involvement is appropriate and inappropriate. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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