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991.
Raes Filip; Hermans Dirk; Williams J. Mark G.; Beyers Wim; Eelen Paul; Brunfaut Els 《Canadian Metallurgical Quarterly》2006,115(4):699
Reduced autobiographical memory (AM) specificity is a known vulnerability factor for depression. AM specificity was investigated as a predictor of depression with the Autobiographical Memory Test (J. M. G. Williams & K. Broadbent, 1986). When baseline depression scores were partialed, reduced AM specificity to negative cue words predicted higher levels of depression at 7-month follow-up. Once rumination was taken into account by means of the Rumination on Sadness Scale (M. Conway, P. A. R. Csank, S. L. Holm, & C. K. Blake, 2000), AM specificity no longer predicted depression, suggesting that the predictive value of AM specificity observed in previous studies might be--at least partly--explained as an effect of rumination. Further mediation analyses indeed revealed support for rumination as a mediator of the relation between reduced AM specificity and poor outcome of depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
This paper examines the outcomes of alternative policy targets for monetary policy in an open economy subject to terms of trade shocks and with less-than-perfect exchange-rate pass through. The central bank also learns the evolution of inflation and output growth in the design of its policy rules. We show that a Taylor rule for the interest rate, based on inflation and output gap targets, when terms of trade shocks are positive, yields more beneficial welfare distributions than comparable feedback rules based only on an inflation target.
JEL classification: E5, F4 相似文献
993.
Roland Bouffanais Michel O. Deville Paul F. Fischer Emmanuel Leriche Daniel Weill 《Journal of scientific computing》2006,27(1-3):151-162
This paper presents the large-eddy simulation of the lid-driven cubic cavity flow by the spectral element method (SEM) using the dynamic model. Two spectral filtering techniques suitable for these simulations have been implemented. Numerical results for Reynolds number Re=12,000 are showing very good agreement with other experimental and DNS results found in the literature. 相似文献
994.
Paul Williams 《Multibody System Dynamics》2006,16(4):351-374
Towed-aerial cable systems are often used for towing decoys from aircraft and for collecting electromagnetic data from low
altitudes. Airborne cable systems are typically controlled by maneuvering the aircraft, which can limit the safe altitude
of the towed-sensor package. In this paper, a real-time optimal control strategy for controlling a towed-cable system is proposed
that uses cable winch control to control the altitude of the towed-body. The controller is based on a receding horizon control
approach, where the aircraft senses the terrain profile ahead of the towed-body with a relatively short time horizon. This
information is sent to the controller, which updates the cable winch reel acceleration to safely avoid colliding with the
terrain, while keeping the towed-sensor close to the desired altitude for obtaining good measurements. The controller is developed
for a simplified system model and implemented in a multibody cable system model that incorporates cable flexibility and elasticity. 相似文献
995.
A virtual machine monitor (VMM) allows a single computer to run two or more operating systems at the same time. VMMs are relatively simple and are typically built to high assurance standards, which means that the quality of isolation provided by a virtual machine monitor is usually greater than that which can be achieved with a general-purpose operating system. This paper discusses how the flexibility afforded by multiple OS environments and the robust isolation provided by a virtual machine monitor can be used to improve client PC security. A prototype system is also described.This paper is neither a product announcement nor an official Microsoft position paper, but rather it is a discussion of interesting configuration options that can be constructed using existing Microsoft and third-party products: in this case two or more operating systems running in conjunction with a virtual machine monitor. 相似文献
996.
The accuracy of a non-pixel-based skeletonization method is largely dependent on the contour information chosen as input. When using a Constrained Delaunay Triangulation to construct an object's skeleton, a number of contour pixels must be chosen as a basis for triangulation. This paper presents a new method of selecting these contour pixels. A new method for measuring skeletonization error is proposed, which quantifies the deviation of a skeleton segment from the true medial axis of a stroke in an image. The goal of the proposed algorithm is to reduce this error to an acceptable level, whilst retaining the superior efficiencies of previous non-pixel-based techniques. Experimental results show that the proposed method is adept at following the medial axis of an image, and is capable of producing a skeleton that is confirmed by a human's perception of the image. It is also computationally efficient and robust against noise. 相似文献
997.
The problems of robust stability and robust stabilization of uncertain linear systems with distributed delay occurring in the state variables are studied in this paper. The essential requirement for the uncertainties is that they are norm-bounded with known bounds. Conditions for the robust stability of distributed time delay systems are given and a design method for the robust stabilizing control law of the uncertain systems is presented. The proposed method is applied to the stabilization of combustion in the chamber of a liquid monopropellant rocket motor. It is found that the combustion can be robustly stabilized when the two parameters pressure exponent γ and maximal time lag r vary in specified intervals, respectively. 相似文献
998.
When evaluating new protocols and algorithms it is often desirable to be able to rapidly build a specialized simulator from scratch. The advantage of this approach is that software designers can avoid the often‐steep learning curve associated with using existing simulators, and that specialized simulators can have significant computational advantages over general‐purpose programs. The drawback is that simulators can be complex to develop and debug. This paper describes our experiences developing SESAME, a Java‐based simulator designed to analyze multicast protocol performance. By using an appropriate set of design patterns we were able to rapidly develop a reusable and easy‐to‐implement framework for multicast algorithm and protocol analysis. We developed several useful approaches for rapid simulation development, including a multicast visualization tool and techniques for simulating concurrent processing within a computer network that substantially simplified code development and maintenance. Owing to performance concerns, we also ran an extensive series of performance tests of different priority queue implementations. Our design approach and the lessons that we learned in developing SESAME can be applied to rapid simulation development in general. Further, our performance results suggest that by using commercial off‐the‐shelf Java development environments it is possible to obtain sufficient performance for many time‐sensitive applications such as discrete event simulation. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
999.
Chun‐Wen Paul Huang Atef Z. Elsherbeni Charles E. Smith Po‐Leng Chin 《国际射频与微波计算机辅助工程杂志》2002,12(2):148-158
Ribbon cables have been widely used as subsystem interconnections in a large number of digital systems, because they can convey numerous bits of a digital signal simultaneously. In this article, finite difference and finite difference time domain (FDTD) methods are used to analyze and optimize the electrostatic analysis design of ribbon cables, and measurements are used to verify the numerical results. © 2002 Wiley Periodicals, Inc. Int J RF and Microwave CAE 12: 148–158, 2002. 相似文献
1000.
Prof. Dr. Paul Alpar 《WIRTSCHAFTSINFORMATIK》2002,44(1):29-40
The potential of Electronic Data Interchange (EDI) has not yet been fully realized despite the existence of appropriate standards and technologies. Service providers in this area play an important role as providers of the infrastructure, providers of conversion programs, or consultants. This paper examines the critical success factors of EDI service providers as perceived by them and their customers. It finds that the views of these groups are partly divergent, especially with respect to the need for knowledge of business processes. The findings can help providers to improve their services for their own benefit and the benefit of their users. 相似文献