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41.
42.
Once segmentation of 3D surface data of a rock pile has been performed, the next task is to determine the visibility of the surface rocks. A region boundary-following algorithm that accommodates irregularly spaced 3D coordinate data is presented for determining this visibility. We examine 3D surface segmentations of laboratory rock piles and determine which regions in the segmentation correspond to entirely visible rocks, and which correspond to overlapped or partially visible rocks. This is a significant distinction as it allows accurate size determination of entirely visible rocks, separate handling of partially visible rocks, and prevents erroneous bias resulting from mishandling partially visible rocks as smaller entirely visible rocks. Literature review indicates that other rock pile sizing techniques fail to make this distinction. The rock visibility results are quantified by comparison to manual surface classifications of the laboratory piles and the size results are quantified by comparison to the sieve size. 相似文献
43.
Adaptive Hypermedia 总被引:9,自引:2,他引:7
Adaptive hypermedia is a relatively new direction of research on the crossroads of hypermedia and user modeling. Adaptive hypermedia systems build a model of the goals, preferences and knowledge of each individual user, and use this model throughout the interaction with the user, in order to adapt to the needs of that user. The goal of this paper is to present the state of the art in adaptive hypermedia at the eve of the year 2000, and to highlight some prospects for the future. This paper attempts to serve both the newcomers and the experts in the area of adaptive hypermedia by building on an earlier comprehensive review (Brusilovsky, 1996; Brusilovsky, 1998). 相似文献
44.
The paper describes results of a longitudinal study of developments in the area of software product and process quality improvement within a Hungarian software company, IQSOFT Ltd. This company has been active in this area since 1993, trying to build, introduce and maintain an efficiently working quality management system which, e.g., fulfils the ISO 9001 requirements, allows steady software process improvement and, at the same time, conforms to company's own needs. Over the last eight years five phases could be distinguished. Each phase is described shortly, following the same structure, namely: basic starting points, key problem areas, literature consulted, activities and design executed, reflections on what happened and why. The lessons resulting from the analysis of this case have been formulated in terms of guidelines. We feel that these are applicable to any low maturity software development organisation embarking on a product or process quality improvement endeavour. These guidelines are developed around a framework containing the basic issues of software production (project management, technical processes and products). The guidelines advocate a careful step-by-step development of definitions, quality characteristics, and metrics related to these objects while at the same time developing and introducing the associated process. 相似文献
45.
A longitudinal assessment of the introduction of new office technologies into a multinational bank was conducted using both task diaries and semi-structured interviews. Task diaries were administered prior to the introduction of microcomputers, several months after the introduction and several years later. Semi-structured interviews were completed after the second task diary. The assessment provides evidence of how offices adapt to changing electronic tookits. The asssessment provides ergonomists with a usable list of taks activities and the effects on task variability of the adoption of microcomputers into the work routine. It shows that when support staff are asked to use a new computer they must choose what other tasks to cut back on, which has consequences for the overall work process. Overtime increased 170% after the introduction of the computer. In a culture where professional staff have high expectations of support staff this has consequences for working relationships in terms of perceptions of the computer's utility. Support staff and professional staff differ in perceptions of control, time-saving and ability to make corrections. The assessment demonstrates the importance of multiple measurement instruments in tracking the effects of technological change on the work process. In conclusion, it is noted that the introduction of new technologies into the office must be considered in the broader office context to avoid the unintended consequences often reported in other case studies. 相似文献
46.
I‐Ching Hsu 《Software》2012,42(10):1211-1227
Web 2.0 Mashups offer entirely new opportunities for context‐aware application (CAA) developers by integrating Web 2.0 technologies to facilitate interoperability among heterogeneous context‐aware systems. From a software engineering perspective, a visualized approach for Web 2.0‐based CAA modeling is crucial. Current CAA development, however, cannot provide a conceptual model for Web 2.0‐based CAA. Therefore, the development efficiency and potential for reuse are decreased. The UML is a general purpose modeling language with potential for use in many application domains. However, UML often lacks elements needed to model concepts in specific domains, such as Web 2.0‐based CAA modeling. To address the above issues, this study presents the Web 2.0‐based CAA UML profile, a UML profile for modeling Web 2.0‐based CAA. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
47.
《Behaviour & Information Technology》2012,31(2):185-204
Researchers and practitioners in the field of information and communication technologies (ICT) have for a while been embracing the concepts of user and consumer experience as well as emotions in design, encouraging the industry to emphasise hedonic and symbolic qualities of products and services, over and beyond their utilitarian characteristics. However, the idea that mobile phone users, for instance, seek increasingly experience-rich, personalised products can not be taken for granted. Therefore, it is valuable to investigate the degree to which users really share designers' increasingly socio-emotional stances. The presented longitudinal study investigated users' mobile phone-related product meaning, particularly its development from 2004 to 2008. Product meaning was conceptualised in terms of an affective-cognizant choice mode dimension complemented by items capturing utilitarian, hedonic, and symbolic facets of the construct. The findings provide grounds for raising an important discussion about a possible pragmatic shift in product meaning, away from emotional and holistic, towards piecemeal and rational valuation. This would obviously challenge current design maxims. Linking these results to users' personality and mobile phone ownership history, subgroups with notably dissimilar product meaning development could be distinguished mainly with regard to levels of neuroticism, extraversion and brand loyalty – however, not gender. 相似文献
48.
《Behaviour & Information Technology》2012,31(12):1161-1171
The principal objective of this study was to gain insight into attitude changes occurring during IT acceptance from the perspective of elaboration likelihood model (ELM). In particular, the primary target of this study was the process of IT acceptance through an education program. Although the Internet and computers are now quite ubiquitous, and thus many people can come to an acceptance of IT organically – including acceptance of such products as new released online services or software, some software – most notably programming languages and spreadsheets – may require education programs, and the efficacy of that education may determine the rate of acceptance. Thus, education programs for such IT may be regarded as not only teaching and training how to use the product from a technical standpoint, but also as a process by which program participants are persuaded to have a positive attitude towards accepting the new IT. This study adopted an ELM based longitudinal approach to capture the changes in the roles of persuasion routes and attitude during IT acceptance – in this case, the education program. To validate empirically the suggested model, junior students majoring in business administration, all of whom were taking an Excel class, were surveyed twice – just after mid-term and just after their final exam. These data were analysed via partial least-square method to deduce some possible implications. Our results supported all the hypotheses put forward. 相似文献
49.
结合目前电法勘探数据成图及二维解释的特点及存在的局限性,研究了OpenGL和VC++2005联合编程,结合二维剖面数据特点,研制了基于OpenGL的电法数据三维可视化系统Geo3DVis。Geo3DVis的基本功能包括工区建立、二维解释、三维显示;实现了对二维剖面数据的动态放大、缩小、平移等交互操作。将Geo3DVis应用于实际二维物探数据资料解释,取得了良好的地质效果。 相似文献
50.
地震数据显示是地震资料解释的基础,将数据转换为图形的形式在屏幕上显示出来可以使其更加直观、易于理解。本文在分析了SEGY格式地震数据文件结构的基础上,利用VC++实现了地震数据的准确读取,完成了波形、面积填充和变密度这几种常见地震数据剖面显示方式的绘制。对绘制的原理和过程进行了介绍,并展示了绘制结果。 相似文献