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91.
作者基于Groebner基法和计算机符号处理技术 ,对 3 RSP并联平台机构的位置正解问题进行了符号求解。该法通过对变量排序、建立多项式对的集合、求SP多项式和约简等运算 ,将一组非线性方程组化简为等价的三角化方程组 ,得到了封闭形式的解析解。同时给出了具体数值实例。 相似文献
92.
链轮齿数对链传动动载荷的影响 总被引:1,自引:0,他引:1
在链传动设计中链轮齿数的选择与链节距的选择有关,而分析链轮齿数对动载荷影响时所得的结论也与链节距相关.但作为一独立参数的链轮齿数对链传动动载荷的影响必有其独立的一面.就此分析了链轮齿数对链传动动载荷的影响,并就链传动设计中链轮齿数的选择进行了定性分析. 相似文献
93.
Agent机会发现的一种相关性描述 总被引:2,自引:0,他引:2
机会发现和机会管理(ChanceDiscoveryandChanceManagement)是近年国际上人工智能等领域提出的一个新的研究课题。该文给出一种CD相关性定义来刻画ChanceEvent与agent目标之间的基本联系,为解决ChanceDis-covery的两个基本问题——“特征问题”和“区分问题”——提供了一个初步的方案。 相似文献
94.
A practical implementation of stochastic programming: an application to the evaluation of option contracts in supply chains 总被引:1,自引:0,他引:1
Ch. van Delft Author Vitae 《Automatica》2004,40(5):743-756
Stochastic programming is a powerful analytical method in order to solve sequential decision-making problems under uncertainty. We describe an approach to build such stochastic linear programming models. We show that algebraic modeling languages make it possible for non-specialist users to formulate complex problems and have solved them by powerful commercial solvers. We illustrate our point in the case of option contracts in supply chain management and propose a numerical analysis of performance. We propose easy-to-implement discretization procedures of the stochastic process in order to limit the size of the event tree in a multi-period environment. 相似文献
95.
Quantifying target spotting performances with complex geoscientific imagery using ERP P300 responses
《International journal of human-computer studies》2014,72(3):275-283
Geoscientific data interpretation is a challenging task, which requires the detection and synthesis of complex patterns within data. As a first step towards better understanding this interpretation process, our research focuses on quantitative monitoring of interpreters' brain responses associated with geoscientific target spotting. This paper presents a method that profiles brain responses using electroencephalography (EEG) to detect P300-like responses that are associated with target spotting for complex geoscientific data. In our experiment, eight interpreters with varying levels of expertise and experience were asked to detect features, which are likely to be copper–gold rich porphyry systems within magnetic geophysical data. The target features appear in noisy background and often have incomplete shape. Magnetic images with targets and without targets were shown to participants using the “oddball” paradigm. Event related potentials were obtained by averaging the EEG epochs across multiple trials and the results show delayed P3 response to the targets, likely due to the complexity of the task. EEG epochs were classified and the results show reliable single trial classification of EEG responses with an average accuracy of 83%. The result demonstrated the usability of the P300-like responses to quantify the geoscientific target spotting performances. 相似文献
96.
Online social media exhibit massive organizational event relevant messages, and the well categorized event information can be useful in many real-world applications. In this paper, we propose a research framework to extract high quality event information from massive online media data. The main contributions lie in two aspects: First, we present an event-extraction and event-categorization system for online media data; second, we present a novel approach for both discovering important event categories and classifying extracted events based on word representation and clustering model. Experimental results with real dataset show that the proposed framework is effective to extract high quality event information. 相似文献
97.
98.
In part I of the paper, an assembly building was analyzed in order to compute the failure probabilities, and thus the safety level, of current code-compliant buildings. In this second part, various fire protection systems are modeled within the fire and egress simulations in order to quantify their magnitude of impact. Since all fire protection systems can fail to perform as designed on demand, the potential failure along with its probability is accounted for in an event tree analysis. Comparing the resulting failure probabilities of the performance-based analyses with and without fire protection systems yields information about the magnitude of impact of the fire protection systems on the level of safety and hence allows a direct, objective, and quantitative comparison to other systems and designs. Accounting for the cost of the systems, a direct cost–benefit analysis can be conducted. 相似文献
99.
The use of the life history calendar (LHC) or the event history calendar as tools for collecting retrospective data has received increasing attention in many fields of social science and medicine. However, little research has examined the use of this method with web-based surveys. In this study, we adapted this method to an on-line setting to collect information about young adults' life histories, sexual behaviors, and substance use. We hypothesized that the LHC method would help respondents to date sensitive and non-sensitive events more precisely than when using a conventional questionnaire. We conducted an experimental design study comparing university students' responses to an on-line LHC and a conventional on-line question list. A test-retest design in which the respondents completed the survey again two weeks later was also applied to test the precision and reliability of the participants' dating of events. The results showed that whereas the numbers of sensitive and non-sensitive events were generally similar for the two on-line questionnaires, the responses obtained with the LHC were more consistent across the two administrations. Analyses of the respondents' on-line behavior while completing the LHC confirmed that respondents used the LHC's graphic interface to correct and reedit previous answers, thus decreasing data errors. 相似文献
100.
With organisations facing significant challenges to remain competitive, Business Process Improvement (BPI) initiatives are often conducted to improve the efficiency and effectiveness of their business processes, focussing on time, cost, and quality improvements. Event logs which contain a detailed record of business operations over a certain time period, recorded by an organisation's information systems, are the first step towards initiating evidence-based BPI activities. Given an (original) event log as a starting point, an approach to explore better ways to execute a business process was developed, resulting in an improved (perturbed) event log. Identifying the differences between the original event log and the perturbed event log can provide valuable insights, helping organisations to improve their processes. However, there is a lack of automated techniques and appropriate visualisations to detect the differences between two event logs. Therefore, this research aims to develop visualisation techniques to provide targeted analysis of resource reallocation and activity rescheduling. The differences between two event logs are first identified. The changes between the two event logs are conceptualised and realised with a number of visualisations. With the proposed visualisations, analysts are able to identify resource- and time-related changes that resulted in a cost reduction, and subsequently investigate and translate them into actionable items for BPI in practice. Ultimately, analysts can make use of this comparative information to initiate evidence-based BPI activities. 相似文献