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31.
Michael J. Doyle 《Journal of Materials Science》1982,17(1):204-210
Fracture of crazes in glassy polymers can occur by a quasi-brittle separation at the interface between the craze and the adjacent bulk. In some grades of polystyrene this type of fracture can take the form of a very regular pattern, the so-called mackerel pattern, of parallel or concentric craze strips as fracture alternates from one side of the craze layer to the other. The alternating pattern of fracture is determined by the coupling between stress waves propagating along the craze—bulk boundaries. 相似文献
32.
The field of systems biology has attracted the attention of biologists, engineers, mathematicians, physicists, chemists and others in an endeavour to create systems-level understanding of complex biological networks. In particular, systems engineering methods are finding unique opportunities in characterizing the rich behaviour exhibited by biological systems. In the same manner, these new classes of biological problems are motivating novel developments in theoretical systems approaches. Hence, the interface between systems and biology is of mutual benefit to both disciplines. 相似文献
33.
Benchmarking nanotechnology for high-performance and low-power logic transistor applications 总被引:1,自引:0,他引:1
Chau R. Datta S. Doczy M. Doyle B. Jin B. Kavalieros J. Majumdar A. Metz M. Radosavljevic M. 《Nanotechnology, IEEE Transactions on》2005,4(2):153-158
Recently there has been tremendous progress made in the research of novel nanotechnology for future nanoelectronic applications. In particular, several emerging nanoelectronic devices such as carbon-nanotube field-effect transistors (FETs), Si nanowire FETs, and planar III-V compound semiconductor (e.g., InSb, InAs) FETs, all hold promise as potential device candidates to be integrated onto the silicon platform for enhancing circuit functionality and also for extending Moore's Law. For high-performance and low-power logic transistor applications, it is important that these research devices are frequently benchmarked against the existing Si logic transistor data in order to gauge the progress of research. In this paper, we use four key device metrics to compare these emerging nanoelectronic devices to the state-of-the-art planar and nonplanar Si logic transistors. These four metrics include: 1) CV/I or intrinsic gate delay versus physical gate length L/sub g/; 2) energy-delay product versus L/sub g/; 3) subthreshold slope versus L/sub g/; and 4) CV/I versus on-to-off-state current ratio I/sub ON//I/sub OFF/. The results of this benchmarking exercise indicate that while these novel nanoelectronic devices show promise and opportunities for future logic applications, there still remain shortcomings in the device characteristics and electrostatics that need to be overcome. We believe that benchmarking is a key element in accelerating the progress of nanotechnology research for logic transistor applications. 相似文献
34.
Fiona Fui-Hoon Nah 《Behaviour & Information Technology》2004,23(3):153-163
Web users often face a long waiting time for downloading Web pages. Although various technologies and techniques have been implemented to alleviate the situation and to comfort the impatient users, little research has been done to assess what constitutes an acceptable and tolerable waiting time for Web users. This research reviews the literature on computer response time and users' waiting time for download of Web pages, and assesses Web users' tolerable waiting time in information retrieval. It addresses the following questions through an experimental study: What is the effect of feedback on users' tolerable waiting time? How long are users willing to wait for a Web page to be downloaded before abandoning it? The results from this study suggest that the presence of feedback prolongs Web users' tolerable waiting time and the tolerable waiting time for information retrieval is approximately 2 s. 相似文献
35.
A heuristic for design of plantwide control strategies is introduced and applied to the millwide control of a previously presented pulp mill benchmark. Two control strategies (decentralized control and unit-based model predictive control) are compared according to their capacity to reduce the total error and maximize the operating profits. The control strategies are studied through closed-loop simulations of the process including several disturbances and setpoint changes in the digester, oxygen reactor, bleach plant, recausticizing plant and lime kiln. 相似文献
36.
This paper describes the design, implementation, and experimental evaluation of a modular and extensible Java? Virtual Machine (JVM) infrastructure, called Jupiter. The infrastructure is intended to serve as a vehicle for our research on scalable JVM architectures for a cluster of PC workstations, with support for shared memory in software. Jupiter is constructed, using a building block architecture, out of many modules with small, simple interfaces. This flexible structure, similar to UNIX® shells that build complex command pipelines out of discrete programs, allows the rapid prototyping of our research ideas by confining changes in JVM design to a small number of modules. In spite of this flexibility, Jupiter delivers good performance. Experimental evaluation of the current implementation of Jupiter using the SPECjvm98 and the EPCC Java Grande single‐threaded and multithreaded benchmarks reflects competitive performance. Jupiter is on average about 2.5 times faster than Kaffe and about 2 times slower than the Sun Microsystems JDK (interpreter versions only). By providing a flexible JVM infrastructure that delivers competitive performance, we believe we have developed a framework that supports further research into JVM scalability. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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M. Calvo C. Hoffman A. Benoit N. Boudou A. Cruciani S. Doyle C. Giordano C. Hoarau H. LeDuc P. Mauskopf A. Monfardini M. Roesch K. Schuster 《Journal of Low Temperature Physics》2012,167(3-4):379-385
Microwave Kinetic Inductance Detectors (MKIDs) have recently drawn the attention of the low-temperature detectors community. Easy fabrication, high sensitivity, small time constants and most notably the intrinsic capability to frequency multiplexing open new possibilities to applications that need very large array sizes and/or high speed read-out. Lumped Element Kinetic Inductance Detectors (LEKIDs) designed and fabricated in our collaboration have already shown good on sky performances, but new developments are needed for future multi-thousands-pixels instruments. In this contribution we present such ongoing developments: a new LEKIDs design, optimized to be dual polarization sensitive; use of new materials such as TiN in order to reach better signal to noise ratios; new solutions to minimize the cross-talk between pixels in order to achieve a better control of the resonance positions in frequency space. We discuss present lab measurements of the optical performances and recent improvements of the read-out electronics. 相似文献
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