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91.
Francesco Bellotti Riccardo Berta Massimiliano Margarone Alessandro De Gloria 《Software》2008,38(12):1241-1259
The RFID technology is becoming ever more popular in the development of ubiquitous computing applications. A full exploitation of the RFID potential requires the study and implementation of human–computer interaction (HCI) modalities to be able to support wide usability by the target audience. This implies the need for programming methodologies specifically dedicated to support the easy and efficient prototyping of applications to have feedback from early tests with users. On the basis of our field‐working experience, we have designed oDect, a high‐level language and platform‐independent application programming interface (API), ad hoc designed to meet the needs of typical applications for mobile devices (smart phones and PDAs). oDect aims at allowing application developers to create their prototypes focusing on the needs of the final users, without having to care about the low‐level software that interacts with the RFID hardware. Further, in an end‐user developing (EUD) approach, oDect provides specific support for the application end‐user herself to cope with typical problems of RFID applications in detecting objects. We describe in detail the features of the API and discuss the findings of a test with four programmers, where we analyse and evaluate the use of the API in four sample applications. We also present results of an end‐user test, which investigated strengths and weaknesses of the territorial agenda (TA) concept. The TA is an RFID‐based citizen guide that aids—through time‐ and location‐based reminders—users in their daily activities in a city. The TA directly exploits EUD features of oDect, in particular concerning the possibility of linking detected objects with custom actions. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
92.
The interaction spaces between instructors and learners in the traditional face-to-face classroom environment are being changed by the diffusion and adoption of many forms of computer-based pedagogy. An integrated understanding of these evolving interaction spaces together with how they interconnect and leverage learning are needed to develop meaningful strategies for effective teaching and learning. The 18i collaborative interaction spaces model was designed based on constructivist principles, and describes 18 mixed instructor–learner spaces contextualized at a finer operational scale that makes explicit a wider range of interactions. The model was implemented during the life cycle of an undergraduate GIS-based multimedia cartography course. One output was the generation of a repository of rule-based trajectory plans for rapid planning and problem solving. The model provides an integrated workflow to manage course contents, products, interactions, individuality, and learning styles in blended environments. 相似文献
93.
The widespread availability of digital learning resources in a variety of media formats offers the possibility to make a profound difference in education. This potential has not been fully realised for range of interrelated reasons. In this paper we study the key characteristics of learning resources that have proved effective in changing learning and teaching, and relate them to existing frameworks for understanding resources. We outline the relationships between resources, their users, and the way they are used, and explore issues that influence practitioners in choosing a particular resource. Our study is based on a review of resources for e-learning and chemistry in post-compulsory education, undertaken for the UK Joint Information Systems Committees (JISC), as part of a wider study examining ‘The Effectiveness of Resources, Tools and Support Services used by Tutors in Designing and Delivering E-Learning Activities’. 相似文献
94.
Michael Creel 《Computational Economics》2008,32(4):343-352
Solving nonlinear macroeconomic models with rational expectations can be time-consuming. This paper shows how the parameterized
expectations algorithm (PEA) can be parallelized to reduce the time needed to solve a simple model by more than 80%. The general
idea of using parallelization applies naturally to other algorithms, as well. This paper is illustrative of the speedup that
can be obtained, and it provides computer code that may serve as an example for parallelization of other algorithms. For those
who would like to use the parallelized PEA, the implementation does not confront end users with the details of parallelization.
To solve a model, it is only necessary to provide ordinary serial code that simulates data from the model. All needed code
is available, on a standalone basis, or pre-installed on ParallelKnoppix (Creel, J Appl Economet 22:215–223, 2007).
相似文献
95.
一种基于MOF技术的网络建模研究与实现 总被引:1,自引:0,他引:1
基于模型驱动架构方法极大提高了软件的开发效率,而模型之间的转换是开发基于模型驱动架构应用工具的关键技术。采用MOF技术建立不同类型模型结构,运用XMI Bus的数据交换技术将MOF和XML很好地结合在一起,极大降低了模型转换的壁垒,使得异构环境下的工具和各种模型间的交互变得简单。本文研究了MOF的相关技术,最后运用该技术实现了网络中的建模过程。 相似文献
96.
Photoshop是众多图形图像软件中的霸主,易用且功能异常强大,处理图片舍我其谁。该文主要介绍了笔者在教学工作中使用Photoshop的一些技巧。 相似文献
97.
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99.
Alex W. Wardrop 《Networks and Spatial Economics》2009,9(1):123-143
The functions of Australia’s railways are divided between the delivery of suburban passenger railway services, long distance
general and intermodal freight services and regional bulk commodity haulage. There is a national interest in the efficient
carriage of export freight flows because Australia is a major trading nation. Australia’s railways are expected play their
part in hauling export commodities. Unsurprisingly, there are conflicting demands on these railways. Hence, universities,
and the industry itself, are directing research and investigation effort into policy, planning, engineering, operational and
human factors matters. A question which then arises is what means could be used to analyse the problems identified during
this research and investigation. This paper is thus concerned with the inter-relationships between the planning, engineering
and operations of railways in Australia. It identifies four areas of analysis associated with the planning and development
of railway infrastructure and operations. It then discusses a range of analytical tools which could be applied to different
components of these analytical areas and critiques their appropriateness from an Australian perspective. Having made this
assessment, the paper uses a recent Australian case study to show how analytical tools could be used and what lessons might
be learnt from the process.
Figure Use of Railway Analysis Tools from an Australian Perspective
相似文献
Alex W. WardropEmail: |
100.
This paper presents an overview and discusses the role of certification in safety-critical computer systems focusing on software,
and partially hardware, used in the civil aviation domain. It discusses certification activities according to RTCA DO-178B
“Software Considerations in Airborne Systems and Equipment Certification” and touches on tool qualification according to RTCA
DO-254 “Design Assurance Guidance for Airborne Electronic Hardware.” Specifically, certification issues as related to real-time
operating systems and programming languages are reviewed, as well as software development tools and complex electronic hardware
tool qualification processes are discussed. Results of an independent industry survey done by the authors are also presented. 相似文献