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151.
Guido Böttcher Dennis Allerkamp Daniel Glöckner Franz-Erich Wolter 《The Visual computer》2008,24(10):911-922
Real-time cloth simulation involves many computational challenges to be solved, particularly in the context of haptic applications,
where high frame rates are necessary for obtaining a satisfying experience. In this paper, we present an interactive cloth
simulation system that offers a compromise between a realistic physics-based simulation of fabrics and a haptic application
meeting high requirements in terms of computation speed. Our system allows the user to interact with the fabric using two
fingers. The required performance of the system is achieved by introducing an intermediate layer responsible for the simulation
of the small part of the surface being in contact with the fingers. Additionally we separate the possible contact situations
into different cases, each being individually handled by a specialised contact algorithm.
相似文献
Franz-Erich WolterEmail: |
152.
Barbara Yersin Jonathan Maïm Fiorenzo Morini Daniel Thalmann 《The Visual computer》2008,24(10):859-870
Real-time crowd motion planning requires fast, realistic methods for path planning as well as obstacle avoidance. In a previous
work (Morini et al. in Cyberworlds International Conference, pp. 144–151, 2007), we introduced a hybrid architecture to handle real-time motion planning of thousands of pedestrians. In this article, we
present an extended version of our architecture, introducing two new features: an improved short-term collision avoidance
algorithm, and simple efficient group behavior for crowds. Our approach allows the use of several motion planning algorithms
of different precision for regions of varied interest. Pedestrian motion continuity is ensured when switching between such
algorithms. To assess our architecture, several performance tests have been conducted, as well as a subjective test demonstrating
the impact of using groups. Our results show that the architecture can plan motion in real time for several thousands of characters.
相似文献
Daniel ThalmannEmail: |
153.
We consider a single machine scheduling problem with simple linear deterioration. Job processing times are assumed to be a simple linear function of a job-dependent growth rate and the job's starting time. We seek an optimal schedule, so as to minimize the total absolute deviation of completion times (TADC). We prove several interesting properties of an optimal schedule, and introduce two efficient heuristics which are tested against a lower bound. 相似文献
154.
This paper reports on a case study of a teacher from a technical education institution who explored the educational affordances of PDA technology over a period of six months. Based on this teacher’s perspectives, the study was designed to inform our own understanding of educational affordances of this new and emerging technology. Understanding of educational affordances is important in the context of planning a suitable intervention to support pedagogically effective integration of PDA technology. The study explicated a set of five affordances of PDA technology: as a multimedia-access tool, connectivity tool, capture tool, representational tool and analytical tool. We call on further research to expand this set into a more comprehensive collage of educational affordances of PDA technology. 相似文献
155.
Inductive transfer with context-sensitive neural networks 总被引:1,自引:1,他引:0
Context-sensitive Multiple Task Learning, or csMTL, is presented as a method of inductive transfer which uses a single output neural network and additional contextual inputs
for learning multiple tasks. Motivated by problems with the application of MTL networks to machine lifelong learning systems,
csMTL encoding of multiple task examples was developed and found to improve predictive performance. As evidence, the csMTL method is tested on seven task domains and shown to produce hypotheses for primary tasks that are often better than standard
MTL hypotheses when learning in the presence of related and unrelated tasks. We argue that the reason for this performance
improvement is a reduction in the number of effective free parameters in the csMTL network brought about by the shared output node and weight update constraints due to the context inputs. An examination
of IDT and SVM models developed from csMTL encoded data provides initial evidence that this improvement is not shared across all machine learning models. 相似文献
156.
Eric C.C. Tsang Chen Degang Daniel S. Yeung 《Computers & Mathematics with Applications》2008,56(1):279-289
The covering generalized rough sets are an improvement of traditional rough set model to deal with more complex practical problems which the traditional one cannot handle. It is well known that any generalization of traditional rough set theory should first have practical applied background and two important theoretical issues must be addressed. The first one is to present reasonable definitions of set approximations, and the second one is to develop reasonable algorithms for attributes reduct. The existing covering generalized rough sets, however, mainly pay attention to constructing approximation operators. The ideas of constructing lower approximations are similar but the ideas of constructing upper approximations are different and they all seem to be unreasonable. Furthermore, less effort has been put on the discussion of the applied background and the attributes reduct of covering generalized rough sets. In this paper we concentrate our discussion on the above two issues. We first discuss the applied background of covering generalized rough sets by proposing three kinds of datasets which the traditional rough sets cannot handle and improve the definition of upper approximation for covering generalized rough sets to make it more reasonable than the existing ones. Then we study the attributes reduct with covering generalized rough sets and present an algorithm by using discernibility matrix to compute all the attributes reducts with covering generalized rough sets. With these discussions we can set up a basic foundation of the covering generalized rough set theory and broaden its applications. 相似文献
157.
Dipl.-Wirt.-Inform. Daniel Beverungen Dr. Ralf Knackstedt Dipl.-Wirt.-Inform. Oliver Müller 《WIRTSCHAFTSINFORMATIK》2008,50(3):220-234
Offering product-service bundles (consisting of products and services) is becoming more important for companies. Modifying the organizational structure of the cooperation as well as adapting to changing customer demands requires versatile information systems. Implementing Service Oriented Architectures (SOA) is one attempt to provide this flexibility. Currently, there is little methodical guidance for the identification, specification and implementation of services as building blocks of Service Oriented Architectures. Accounting for this need, a conceptual approach is designed, which adapts approaches of customer integration, and combines a business and IT analysis. The applicability of the method is demonstrated by designing a Service Oriented Architecture for the recycling of electronic equipment. Implementing services for other product-service bundles will support additional integration scenarios. By standardizing services, a sound integration of products and services can be backed by providing a reference architecture. 相似文献
158.
Kirsten Bobzin Erich Lugscheider Felix Ernst Reimo Nickel Nazlim Bagcivan Daniel Parkot Arne Schlegel Stefania Ferrara Tatyana Kashko Noémi Leick 《Microsystem Technologies》2008,14(12):1887-1894
Nowadays, micro components have to fulfill rising optical requirements for different scientific and industrial fields like
astronomy, medicine or multimedia. For this purpose, advanced miniaturized chip-cameras are produced for the microsystems
engineering market. The assembly and joining technologies play a very important role in the production of these micro components.
Several challenges are associated with the joining of chip-cameras. In this study, the application of the soldering technology
has been considered in order to face these challenges. Two joining technologies have been investigated: active soldering and
transient liquid phase (TLP) bonding. Both soldering processes have shown a big potential for hybrid microsystems joining
in previous studies. For both processes, soldering alloys and parameters have been conceived in order to fulfill the joining
requirements of the micro camera components. For instance, the joining temperature represents a major challenge because the
chip-camera consists of a plastic material, polymethyl methacrylate (PMMA). Therefore, particular attention has been directed
to the soldering as well as to the coating temperature. The experimental investigations concerning the solders application
through physical vapor deposition (PVD) have been supported by finite element method (FEM) simulations. The analysis of the
temperature distribution in the micro components during the coating process was the focus of the calculations. Possible undesirable
local overheated areas of the chip-camera components can be detected through simulation.
相似文献
Tatyana KashkoEmail: |
159.
A dynamic workflow framework for mass customization using web service and autonomous agent techniques 总被引:3,自引:1,他引:2
Daniel J. Karpowitz Jordan J. Cox Jeffrey C. Humpherys Sean C. Warnick 《Journal of Intelligent Manufacturing》2008,19(5):537-552
Custom software development and maintenance is one of the key expenses associated with developing automated systems for mass
customization. This paper presents a method for reducing the risk associated with this expense by developing a flexible environment
for determining and executing dynamic workflow paths. Strategies for developing an autonomous agent-based framework and for
identifying and creating web services for specific process tasks are presented. The proposed methods are outlined in two different
case studies to illustrate the approach for both a generic process with complex workflow paths and a more specific sequential
engineering process. 相似文献
160.
Daniel Cohen-Or 《计算机科学技术学报》2009,24(1):1-5
In recent years we have witnessed a large interest in surface deformation techniques. This has been a reaction that can be
attributed to the ability to develop techniques which are detail-preserving. Space deformation techniques, on the other hand,
received less attention, but nevertheless they have many advantages over surface-based techniques. This paper explores the
potential of these two approaches to deformation and discusses the opportunities that the fusion of the two may lead to.
Electronic Supplementary Material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献