首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1146篇
  免费   12篇
  国内免费   18篇
电工技术   4篇
综合类   42篇
化学工业   30篇
金属工艺   4篇
机械仪表   50篇
建筑科学   50篇
矿业工程   6篇
能源动力   12篇
轻工业   19篇
水利工程   5篇
石油天然气   2篇
武器工业   1篇
无线电   17篇
一般工业技术   123篇
冶金工业   339篇
原子能技术   4篇
自动化技术   468篇
  2021年   11篇
  2020年   20篇
  2019年   9篇
  2018年   11篇
  2017年   25篇
  2016年   39篇
  2015年   50篇
  2014年   64篇
  2013年   100篇
  2012年   71篇
  2011年   90篇
  2010年   76篇
  2009年   61篇
  2008年   69篇
  2007年   65篇
  2006年   62篇
  2005年   38篇
  2004年   35篇
  2003年   44篇
  2002年   43篇
  2001年   25篇
  2000年   9篇
  1999年   4篇
  1998年   8篇
  1997年   16篇
  1996年   6篇
  1995年   5篇
  1994年   6篇
  1992年   4篇
  1987年   3篇
  1986年   3篇
  1984年   2篇
  1983年   3篇
  1981年   2篇
  1976年   2篇
  1974年   2篇
  1971年   2篇
  1967年   6篇
  1966年   6篇
  1965年   11篇
  1964年   14篇
  1963年   2篇
  1962年   7篇
  1961年   2篇
  1960年   5篇
  1958年   5篇
  1957年   5篇
  1956年   6篇
  1955年   5篇
  1954年   3篇
排序方式: 共有1176条查询结果,搜索用时 0 毫秒
81.
Exploring the design space of robots: Children''s perspectives   总被引:2,自引:0,他引:2  
Children's perceptions and evaluations of different robot designs are an important unexplored area within robotics research considering that many robots are specifically designed for children. To examine children's feelings and attitudes towards robots, a large sample of children (N = 159) evaluated 40 robot images by completing a questionnaire for each image, which enquired about robot appearance, robot personality dimensions and robot emotions. Results showed that depending on a robot's appearance children clearly distinguished robots in terms of their intentions (i.e. friendly vs. unfriendly), their capability to understand, and their emotional expression. Results of a principal components analysis of the children's ratings of the robots' personality attributes revealed two dimensions labelled ‘Behavioural Intention’ and ‘Emotional Expression’. Robots were classified according to their scores on these two dimensions and a content analysis of their appearance was conducted in an attempt to identify salient features of different robot personalities. Children judged human-like robots as aggressive, but human–machine robots as friendly. Results on children's perceptions of the robots' behavioural intentions provided tentative empirical support for the Uncanny Valley, hypothesized by (Mori, M., 1970), reflecting a situation where robots are very human-like, but still distinguishable from humans, evoking a feeling of discomfort or repulsion. The paper concludes with a discussion of design implications for robots, and the use of robots in educational contexts.  相似文献   
82.
In this paper, a multiproduct inventory control problem is considered in which the periods between two replenishments of the products are assumed independent random variables, and increasing and decreasing functions are assumed to model the dynamic demands of each product. Furthermore, the quantities of the orders are assumed integer-type, space and budget are constraints, the service-level is a chance-constraint, and that the partial back-ordering policy is taken into account for the shortages. The costs of the problem are holding, purchasing, and shortage. We show the model of this problem is an integer nonlinear programming type and to solve it, a harmony search approach is used. At the end, three numerical examples of different sizes are given to demonstrate the applicability of the proposed methodology in real world inventory control problems, to validate the results obtained, and to compare its performances with the ones of both a genetic and a particle swarm optimization algorithms.  相似文献   
83.
With interaction across social networking sites (SNSs) becoming more prominent, the ability to accurately judge another's personality through these digital platforms is an important area of investigation. A number of studies demonstrate that SNSs can be an effective means of communicating information on personality (Evans, Gosling & Carroll, 2008). Much less research has examined the online cues that people use when forming their impressions of another's personality. The current research adopted a mixed methods approach to examine 1) accuracy of first impressions formed on the basis of viewing a person's Facebook behaviour and 2) how judgements are formed. Findings suggested that the traits of openness and conscientiousness can be judged most accurately through observing Facebook behaviour. To explore the cues used in forming personality judgements, thematic analysis was undertaken. This revealed six information ‘cues’ including; (1) vocabulary of target, (2) photographs, (3) written online interactions, (4) relationships with others, (5) health status and, (6) occupational status. Findings are discussed in terms of Funder's Realistic Accuracy Model (1995, 1999) along with limitations and suggestions for future research.  相似文献   
84.
This study examined whether the purposes of Facebook usage is associated with gender and big five personalities in a sample of Turkish university students. Seven hundred and fifty one students filled in a set of questionnaires. While males use Facebook to express themselves, meet new people, and store and organize things more, females use Facebook for educational purposes. Agreeable and conscientious people use Facebook to maintain existing relationship more. It was concluded that gender and agreeableness, which is one of the personality types, are significant variables on the purposes of Facebook usage.  相似文献   
85.
The combined use of computers and telecommunications and the latest evolution in the field of Artificial Intelligence brought along new ways of contracting and of expressing will and declarations. The question is, how far we can go in considering computer intelligence and autonomy, how can we legally deal with a new form of electronic behaviour capable of autonomous action? In the field of contracting, through Intelligent Electronic Agents, there is an imperious need of analysing the question of expression of consent, and two main possibilities have been proposed: considering electronic devices as mere machines or tools, or considering electronic devices as legal persons. Another possibility that has been frequently mentioned consists in the application of the rules of agency to electronic transactions. Meanwhile, the question remains: would it possible, under a Civil Law framework, to apply the notions of “legal personhood” and “representation” to electronic agents? It is obvious that existing legal norms are not fit for such an endeavouring challenge. Yet, the virtual world exists and it requires a new but realistic legal approach on software agents, in order to enhance the use of electronic commerce in a global world.  相似文献   
86.
This study deals with a recycling system with two competing brewers. It is assumed that they coordinate their manufacturing operations through standardization of their glass bottles for easy implementation of extended producer responsibility (EPR). Immediate benefits from the standardization are three folds. Firstly, the sorting and exchange processes of the bottles collected for reuse by each brewer become no longer necessary. Secondly, cost reduction is achieved through streamlining of collection and reuse processes. Finally, under the stochastic demand of glass bottles their inventory holding costs and lost sales cost are reduced via inventory pooling. Through the development of the mathematical models we determine an optimal operation policy of the two brewers that maximizes the sum of benefits obtained from standardization. Numerical examples are solved to show the validity of the model. Sensitivity tests are also performed to examine the effects of system parameters on the objective function value and decision variables.  相似文献   
87.
In this paper, we consider multi-inventory systems in the presence of uncertain demand. We assume that (i) demand is unknown but bounded in an assigned compact set and (ii) the control inputs (controlled flows) are subject to assigned constraints. Given a long-term average demand, we select a nominal flow that feeds such a demand. In this context, we are interested in a control strategy that meets at each time all possible current demands and achieves the nominal flow in the average. We provide necessary and sufficient conditions for such a strategy to exist and we characterize the set of achievable flows. Such conditions are based on linear programming and thus they are constructive. In the special case of a static flow (i.e. a system with 0-capacity buffers) we show that the strategy must be affine. The dynamic problem can be solved by a linear-saturated control strategy (inspired by the previous one). We provide numerical analysis and illustrative examples.  相似文献   
88.
高效的库存管理是实现企业信息化中的重要环节。以ASP.NET和SQL Server为技术支持,以B/S模式为架构,用软件工程的指导思想开发库存管理系统。实践证明利用该技术开发的基于Web端的企业库存管理系统简单易用,可以很好的提高企业库存管理的工作效率。  相似文献   
89.
It is well established in the psychology literature that personality predicts performance to some degree. However, personality neither solely nor directly predicts outcomes. Rather, performance and outcomes unfold through context-specific mediating constructs. This study identified two constructs that mediate the relationship between proactivity and perceived control of time in e-mail use and tested the model with data from 251 knowledge workers. The results show that proactivity predicts the perceived control of time in e-mail use through both e-mail-specific time management behavior and e-mail self-efficacy. Further, greater e-mail self-efficacy leads to improved e-mail-specific time management behavior.  相似文献   
90.
The inventory, routing and scheduling decisions are three major driving factors for supply chain performance. Since they are related to one another in a supply chain, they should be determined simultaneously to improve the decision quality. In the past, the inventory policy, vehicle routing and vehicle scheduling are determined sequentially and separately. Hence, the total cost (inventory, routing and vehicle costs) would increase. In this paper, an integrated model for the inventory routing and scheduling problem (IRSP) is proposed. Since searching for the optimal solution for this model is a non-polynomial (NP) problem, a metaheuristic, variable neighborhood search (VNS), is proposed. The proposed method was compared with other existing methods. The experimental results indicate that the proposed method is better than other methods in terms of average cost per day.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号