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991.
Gil-López Cristina Guixeres Jaime Moghaddasi Masoud Khatri Jaikishan Marín-Morales Javier Alcañiz Mariano 《Virtual Reality》2023,27(3):1937-1966
Virtual Reality - The use of virtual reality (VR) technology in the context of retail is a significant trend in current consumer research, as it offers market researchers a unique opportunity to... 相似文献
992.
José M. Cañete-Valdeón Fernando Enríquez Javier Ortega Ernesto Veláquez 《Information Processing Letters》2008,107(6):221-229
Use cases constitute a popular technique to problem analysis, partly due to their focus on thinking in terms of the user needs. However this is not a guarantee for discovering all the subproblems that compose the structure of a given software problem. Moreover, a rigorous application of the technique requires a previous consensus about the meaning of I. Jacobson's statement “a use case must give a measurable value to a particular actor” (The Rational Edge, March 2003). This paper proposes a particular characterisation of the concept of “value” with the purpose of problem structuring. To this aim we base on the catalogue of frames for real software problems proposed by M. Jackson (Problem Frames, 2001) and we reason about what could be valuable for the user on each problem class. We illustrate our technique with the analysis of a web auction problem. 相似文献
993.
Integrated multiobjective optimization and a priori preferences using genetic algorithms 总被引:1,自引:0,他引:1
One of the tasks of decision-making support systems is to develop methods that help the designer select a solution among a set of actions, e.g. by constructing a function expressing his/her preferences over a set of potential solutions. In this paper, a new method to solve multiobjective optimization (MOO) problems is developed in which the user’s information about his/her preferences is taken into account within the search process. Preference functions are built that reflect the decision-maker’s (DM) interests and use meaningful parameters for each objective. The preference functions convert these objective preferences into numbers. Next, a single objective is automatically built and no weight selection is performed. Problems found due to the multimodality nature of a generated single cost index are managed with Genetic Algorithms (GAs). Three examples are given to illustrate the effectiveness of the method. 相似文献
994.
995.
In this paper we define the weighted serial cost sharing rule for the cost allocation problem. We apply this new rule to the problem of sharing delay costs in a PERT network. This rule belongs to the Core and is the Weighted Shapley Value for a particular game. Furthermore, we present a characterization of this rule and a polynomial algorithm for its calculation. 相似文献
996.
Juan-Antonio Fernndez-Madrigal Cipriano Galindo Javier Gonzlez Elena Cruz-Martín Ana Cruz-Martín 《Robotics and Computer》2008,24(1):150-166
One of the most evident characteristics of robotic applications is heterogeneity: large robotic projects involve many different researchers with very different programming needs and areas of research, using a variety of hardware and software that must be integrated efficiently (i.e.: with a low development cost) to construct applications that satisfy not only classic robotic requirements (fault-tolerance, real-time specifications, intensive access to hardware, etc.) but also software engineering aspects (reusability, maintainability, etc.). Most existing solutions to this problem either do not deal with such heterogeneity or do not cover specific robotic needs. In this paper we propose a framework for the integration of heterogeneous robotic software through a software engineering approach: the BABEL development system, which is aimed to cover the main phases of the application lifecycle (design, implementation, testing, and maintainance) when unavoidable heterogeneity conditions are present. The capabilities of our system are shown by its support for designing and implementing diverse real robotic applications that use several programming languages (C, C++, JAVA), execution platforms (RT-operating systems, MS-Windows, no operating system at all), communication middleware (CORBA, TCP/IP, USB), and also a variety of hardware components (Personal Computers, microcontrollers, and a wide diversity of sensor and actuator devices in mobile robots and manipulator arms). 相似文献
997.
Javier Moreno-Valenzuela Víctor Santibáñez Ricardo Campa 《Journal of Intelligent and Robotic Systems》2008,51(1):65-88
The trajectory tracking of robot manipulators is addressed in this paper. Two important practical situations are considered:
the fact that robot actuators have limited power, and that only position measurements are carried out. Let us notice that
a few solutions for the torque-bounded OFT (output feedback tracking) control has been proposed. In this paper we contribute
to this subject by presenting a class of OFT controllers for torque-constrained robots. The theory of singularly perturbed
systems is crucial in the analysis of the closed-loop system trajectories. As a second contribution of this paper, we present
a detailed experimental study of six control schemes, which were tested in a two degrees-of-freedom direct-drive robot, confirming
the advantages of the proposed methodology. 相似文献
998.
From human regulations to regulated software agents’ behavior 总被引:2,自引:0,他引:2
Javier Vázquez-Salceda Huib Aldewereld Davide Grossi Frank Dignum 《Artificial Intelligence and Law》2008,16(1):73-87
In order to design and implement electronic institutions that incorporate norms governing the behavior of the participants
of those institutions, some crucial steps should be taken. The first problem is that human norms are (on purpose) specified
on an abstract level. This ensures applicability of the norms over long periods of time in many different circumstances. However,
for an electronic institution to function according to those norms, they should be concrete enough to be able to check them
run time. A second problem is that norms describe which behavior is desirable and permitted, but not how this is achieved
in an institution. In the “real world" regulations often indicate procedures for implementing and enforcing the law. Likewise
we should devise means to annotate the norms with practical aspects such as enforcement mechanisms, sanctions, etc. in order
to get requirements for an institution that will enforce norms (by either constraining behavior within the norms or reacting
to violation of the norms). The choice of which kind of mechanism is chosen is not a normative one, but usually based on criteria
of efficiency and/or feasibility of the mechanism. In this paper we present our view on how to approach these problems and
other related issues to be solved in order to develop e-institutions capable to operate in complex, highly regulated scenarios.
相似文献
Frank DignumEmail: |
999.
A novel conductimetric immunosensor for atrazine detection has been designed and developed. This immunosensor is mainly based on antibodies labelled with gold nanoparticles. Additionally, the immunosensor consists of an array of two coplanar non-passivated interdigitated metallic μ-electrodes (IDμE) and immunoreagents specifically developed to detect this pesticide. The chemical recognition layer was covalent immobilized on the interdigital space. Immunochemical detection of the concentration of atrazine is achieved by a competitive reaction that occurs before the inclusion of the labelled antibodies. It is shown that the gold nanoparticles provide an amplification of the conductive signal and hence makes possible to detect atrazine by means of simple DC measurements.The conductimetric immunosensor and its biofunctionalization steps have been characterized by chemical affinity methods and impedance spectroscopy.This work describes the immunosensor structure, fabrication, physico-chemical and analytical characterization, and the immunosensor response using conductivity measurements. The immunosensor developed detects atrazine with limits of detection in the order of 0.1–1 μg L−1, far below the maximum residue level (MRL) (100 μg L−1) established by European Union (EU) for residues of this herbicide in the wine.Although in this paper the competitive reaction occurs in buffer, an initial study of the wine matrix effect is also described. 相似文献
1000.
Victor F. Rodriguez-Galiano Eulogio Pardo-Igúzquiza Mario Chica-Olmo Javier Mateos Juan P. Rigol-Sánchez Miguel Vega 《International journal of remote sensing》2013,34(20):6574-6599
This article compares a set of relevant methods, based on different mathematical approaches, for Landsat 7 Enhanced Thematic Mapper Plus (ETM+) pansharpening. These are classical procedures such as principal component analysis and fast intensity hue saturation; methods based on wavelet transforms, such as wavelet à trous, additive wavelet luminance proportional and multidirectional–multiresolution methods; a method of a geostatistical nature, called downscaling cokriging (DCK); and finally, a Bayesian method (1cor). The comparison of the fused images is based on the qualitative and quantitative evaluation of their spatial and spectral characteristics by calculating statistical indices and parameters that measure the quality and coherence of the images. Moreover, the quality of the spectral information is studied indirectly by means of the Iterative Self-Organizing Data Analysis Technique (ISODATA) classification of the products of fusion. The results show that DCK and 1cor methods yielded better results than the wavelet-based methods. Particularly, DCK does not introduce artefacts in the estimation of the digital numbers corresponding with the source multispectral image and, therefore, it can be considered as the most coherent method. 相似文献