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91.
Hung-Hsuan Huang Aleksandra Cerekovic Igor S. Pandzic Yukiko Nakano Toyoaki Nishida 《AI & Society》2009,24(3):225-235
Embodied conversational agents (ECAs) are computer-generated, human-like characters that interact with human users in face-to-face
conversations. ECA is a powerful tool for representing cultural differences and is suitable for interactive training or edutainment
systems. This article presents preliminary results from the development of a culture-adaptive virtual tour guide agent for
serving Japanese, Croatian, and general Western users by displaying appropriate verbal and non-verbal behaviors. It is being
implemented in Generic ECA Framework, a modular framework for developing ECAs. Dividing the ECA functions into reusable and
loosely coupled modules minimizes the effort required to implement additional behavior and facilitates incremental scale up
of the system. 相似文献
92.
93.
Ethan J. Kubatko Shintaro Bunya Clint Dawson Joannes J. Westerink Chris Mirabito 《Journal of scientific computing》2009,40(1-3):315-339
We present a comparative study of two finite element shallow water equation (SWE) models: a generalized wave continuity equation based continuous Galerkin (CG) model—an approach used by several existing SWE models—and a recently developed discontinuous Galerkin (DG) model. While DG methods are known to possess a number of favorable properties, such as local mass conservation, one commonly cited disadvantage is the larger number of degrees of freedom associated with the methods, which naturally translates into a greater computational cost compared to CG methods. However, in a series of numerical tests, we demonstrate that the DG SWE model is generally more efficient than the CG model (i) in terms of achieving a specified error level for a given computational cost and (ii) on large-scale parallel machines because of the inherently local structure of the method. Both models are verified on a series of analytic test cases and validated on a field-scale application. 相似文献
94.
采用非线性有限元方法,对循环荷载下圆柱和Ⅰ型钢筋混凝土剪力墙进行试验,通过能量消耗分析评估其损伤。首先,通过对荷载-位移关系、裂缝情况的研究以及经过分析所得的总应变能与试验加载能量的比较,验证分析方法的有效性。其次,对能量消耗分布以及钢筋和混凝土的配置进行研究。研究表明:能量消耗是评估剪力墙损伤的有效方法。 相似文献
95.
We propose sealing techniques for medical hollow fibers to protect the inner surface of fibers from debris or water that scatters from targets. First, hollow fibers are sealed with a film of polymer that is easily formed by use of a dipping technique. The transmission loss of 20-microm-thick sealing film was 0.2 dB for Er:YAG laser light, and the maximum energy that is available for the film was 180 mJ. Second, a sealed glass cap was applied to the output end of hollow fiber. The silica-glass cap with a wall thickness of 400 microm shows a transmission loss of 0.5 dB and was not damaged by radiation of 400-mJ energy pulses. 相似文献
96.
Koga Y Kobayashi K Yang J Nakano H Yamane T 《Journal of Bioscience and Bioengineering》2002,94(1):84-86
A mutant library of Burkholderia cepacia lipase KWI-56 was constructed on microplates by a cell-free process and tested with a chromogenic assay. This high-throughput construction system can be used to screen mutant proteins based on their catalytic activity. 相似文献
97.
Self-organizing network services with evolutionary adaptation 总被引:3,自引:0,他引:3
This paper proposes a novel framework for developing adaptive and scalable network services. In the proposed framework, a network service is implemented as a group of autonomous agents that interact in the network environment. Agents in the proposed framework are autonomous and capable of simple behaviors (e.g., replication, migration, and death). In this paper, an evolutionary adaptation mechanism is designed using genetic algorithms (GAs) for agents to evolve their behaviors and improve their fitness values (e.g., response time to a service request) to the environment. The proposed framework is evaluated through simulations, and the simulation results demonstrate the ability of autonomous agents to adapt to the network environment. The proposed framework may be suitable for disseminating network services in dynamic and large-scale networks where a large number of data and services need to be replicated, moved, and deleted in a decentralized manner. 相似文献
98.
The rare earth manganite BaLn2Mn2O7 (Ln=rare earth element) has a Sr3Ti2O7-type layered perovskite structure with double-block oxygen octahedra belonging to the Ruddlesden-Popper-type homologous series AO(ABO3)2. In Pr-manganite, a novel phase transition was first observed in situ at 1040 K by a thermal transmission electron microscope. At 1040 K, reflections began to split along the c-direction in the selected area diffraction pattern. This indicates that a new phase appears in the original phase matrix; the c length of the new phase is 1.5% longer than that of the original phase. After about 5 min, the original phase disappears. No change in the crystal symmetry (space group I4/mmm) is observed above 1040 K. 相似文献
99.
Kiso T Kitahata S Okamoto K Miyoshi S Nakano H 《Journal of Bioscience and Bioengineering》2000,90(6):614-618
To investigate the hydrolysis of glucosyl esters by beta-glucosidase, p-hydroxybenzoyl beta-D-glucose (pHBG) was chemically synthesized. The hydrolytic activity of some beta-glucosidases for pHBG was compared to that for p-nitrophenyl beta-glucoside (pNPG). The Clavibacter michiganense and Flavobacterium johnsonae enzymes could hydrolyze pHBG and steviol glycosides which are natural glucosyl esters. The commercial beta-glucosidase originating from Caldocellum saccharolyticum also hydrolyzes pHBG despite having no activity for steviol glycosides. The beta-glucosidase from Aspergillus niger cleaved the glucosyl ester linkage much more weakly than the glucosidic linkage. The pH-activity profile for the hydrolysis of pHBG was similar to that of pNPG by the C. saccharolyticum beta-glucosidase. The similar profiles for these substrates suggested that the active site for the glucosyl ester chemically resembles that for glucoside with respect to catalysis. Kinetic analysis of the C. saccharolyticum beta-glucosidase for mixed substrates of pHBG and pNPG showed that the hydrolysis of pHBG competed with that of pNPG. This result indicated that there is only one active site for both the glucosyl ester and glucoside. Mass spectroscopic analysis of the hydrolysates of pHBG in H218O suggested that beta-glucosidase hydrolyzes glucosyl esters between the anomeric carbon of glucose and the carbonyl oxygen, not between the carbonyl carbon and the carbonyl oxygen. 相似文献
100.
Nakatsuhara K Mizumoto T Takahashi E Hossain S Saka Y Ma BJ Nakano Y 《Applied optics》1999,38(18):3911-3916
The characteristics of all-optical switching in a waveguide device with a distributed-feedback structure were experimentally investigated. The device was composed of a strip-loaded GaInAsP/InP waveguide and a distributed-feedback structure, which was fabricated by a combination of reactive-ion etching and electron-beam exposure. In the experiments, several optical switching operations were demonstrated. In particular, the all-optical set-reset operation and threshold operation were obtained. 相似文献