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21.
Fusion of multi-sensor information is an important technology, which is growing exponentially due to its tremendous application potential in many areas. Effective fusion of data from sensors is very critical in increasing an intelligent system's capability to accomplish complex tasks. Appropriate fusion technologies are needed to be developed specially when a system requires redundant sensors to be used. More the redundancy in sensors, more is the computational complexity for controlling the system and more is its intelligence level. This research presents a strategy developed for multiple sensor fusion, based on geometric optimization. Each sensor's uncertainty has been modeled using classical Lagrangian optimization techniques. However, the uniqueness and effectiveness of the present technique lies on the fact that starting from the optimized value as initial estimate the accuracy of the sensory information has further been improved up to any pre defined bounded range, by developing two architectures – FFA (fission–fusion architecture) and FDD (fusion in differential domain). Sufficient evidences and analyses have been provided in the paper to show its effectiveness in various applications. 相似文献
22.
Glaucio H. Paulino Ivan F. M. Menezes Marcelo Gattass Subrata Mukherjee 《International journal for numerical methods in engineering》1994,37(9):1511-1530
A Finite Element Graph (FEG) is defined here as a nodal graph (G), a dual graph (G*), or a communication graph (G˙) associated with a generic finite element mesh. The Laplacian matrix ( L (G), L (G*) or L (G˙)), used for the study of spectral properties of an FEG, is constructed from usual vertex and edge connectivities of a graph. An automatic algorithm, based on spectral properties of an FEG (G, G* or G˙), is proposed to reorder the nodes and/or elements of the associated finite element mesh. The new algorithm is called Spectral PEG Resequencing (SFR). This algorithm uses global information in the graph, it does not depend on a pseudoperipheral vertex in the resequencing process, and it does not use any kind of level structure of the graph. Moreover, the SFR algorithm is of special advantage in computing environments with vector and parallel processing capabilities. Nodes or elements in the mesh can be reordered depending on the use of an adequate graph representation associated with the mesh. If G is used, then the nodes in the mesh are properly reordered for achieving profile and wavefront reduction of the finite element stiffness matrix. If either G* or G˙ is used, then the elements in the mesh are suitably reordered for a finite element frontai solver, A unified approach involving FEGs and finite element concepts is presented. Conclusions are inferred and possible extensions of this research are pointed out. In Part II of this work,1 the computational implementation of the SFR algorithm is described and several numerical examples are presented. The examples emphasize important theoretical, numerical and practical aspects of the new resequencing method. 相似文献
23.
Shailendra Joshi Abhijit Mukherjee Siegfried Schmauder 《Computational Materials Science》2003,28(3-4):548-555
The present paper deals with a class of functionally graded materials (FGM), called active FGM that has electro-elastically graded material phases. An active FGM system leads to minimization of stress concentration that arises due to mismatch in the electrical and elastic properties of the constituent phases. This work focuses on the characterization of the through thickness stresses of an active FGM subjected to electrical excitation. The structure is comprised of a substrate, an electro-elastically graded layer and an active layer. A formulation for exact solutions of the system based on Euler–Bernoulli theory is presented. Power-law variation of the composition of the two phases in the graded layer is considered. Performance of linearly gradient FGM for a range of stiffness and electrical property ratios of the active and substrate materials have been studied. It is observed that the electrical strain component and the compositional gradation significantly influence the stress characteristics of the active FGM. 相似文献
24.
H. S. Tripathi B. Mukherjee S. K. Das A. Ghosh G. Banerjee 《Bulletin of Materials Science》2003,26(2):217-220
Mullite was developed by reaction sintering of sillimanite beach sand and calcined alumina. Two varieties of sillimanite beach
sand viz. S and Z having different compositions were selected. Synthesis and properties of mullite were very much dependent
on the sillimanite beach sand composition. Presence of higher amount of impurities in the Z-variety of sillimanite sand favours
the densification by liquid phase formation. Presence of zircon in Z-variety increases the hardness and fracture toughness.
Alumina addition improves the mechanical/thermomechanical properties of the samples. Mullite retains the usual orthorhombic
habit of sillimanite. Rounded to sub rounded zirconia dispersed within the mullite matrix of the sample ZA is noticed. 相似文献
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27.
SP Mahadik S Mukherjee DF Horrobin K Jenkins EE Correnti RE Scheffer 《Canadian Metallurgical Quarterly》1996,63(2-3):133-142
Recent studies have found lower red cell plasma membrane contents and composition of the long chain polyunsaturated essential fatty acid derivatives, particularly arachidonic acid and docosahexaenoic acid, in a subgroup of chronic schizophrenic patients. These fatty acids are particularly enriched in the brain. Red blood cell levels of fatty acids are influenced by diet, medications, and other factors. Cell plasma membrane compositions of arachidonic and docosahexaenoic acids were therefore examined in cultured skin fibroblasts from 12 schizophrenic patients, 8 of whom were drug-naive and in a first episode of psychosis, 6 bipolar patients, and 8 normal control subjects. Docosahexaenoic acid as well as total n-3 essential fatty acid contents were significantly lower in cell lines from schizophrenic patients than in cell lines from bipolar patients and normal subjects, with no difference between the latter two groups. Arachidonic acid levels did not differ across the groups. The essential fatty acid profile observed is consistent with deficient delta-4 desaturase activity in schizophrenic patients. 相似文献
28.
Channel sharing in multi-hop WDM lightwave networks: realizationand performance of multicast traffic
Tridandapani S.B. Mukherjee B. 《Selected Areas in Communications, IEEE Journal on》1997,15(3):488-500
A local lightwave network can be constructed by employing two-way fibers to connect nodes in a passive-star physical topology, and the available optical bandwidth may be effectively accessed by the nodal transmitters and receivers at electronic rates using wavelength division multiplexing (WDM). The number of channels, ω, in a WDM network is limited by technology and is usually less than the number of nodes, N, in the network. We provide a general method using channel sharing to construct practical multi-hop networks under this limitation. Channel sharing may be achieved through time division multiplexing. The method is applied to a generalized shuffle-exchange-based multi-hop architecture, called GEMNET. Multicasting-the ability to transmit information from a single source node to multiple destination nodes-is becoming an important requirement in high-performance networks. Multicasting, if improperly implemented, can be bandwidth-abusive. Channel sharing is one approach toward efficient management of multicast traffic. We develop a general modeling procedure for the analysis of multicast (point-to-multipoint) traffic in shared-channel, multihop WDM networks. The analysis is comprehensive in that it considers all components of delay that packets in the network experience-namely, synchronization, queuing, transmission, and propagation. The results show that, in the presence of multicast traffic, WDM networks with ω相似文献
29.
A Nandakumar N Anantha L Appaji K Swamy G Mukherjee T Venugopal S Reddy M Dhar 《Canadian Metallurgical Quarterly》1996,7(4):405-410
While fairly complete and reliable incident data on childhood cancers are available from the registries in India, mortality and survival information is not. Information concerning the latter was obtained by the Bangalore cancer registry through active follow-up involving visits to homes of patients. Between 1982 and 1989, 617 cases of cancers in childhood were registered, giving an age-standardized incidence rate of 84.8 and 48.4 per million in male and female children, respectively. Active follow-up provided mortality/survival information in 532 or 86.2 percent of these cases. Overall, observed five-year survival was 36.8 percent (both genders combined) with a relative survival of 37.5 percent when childhood mortality in the general population was taken into account. The five-year relative survival was best for thyroid carcinoma (100 percent) followed by Hodgkin's disease (73 percent) and retinoblastoma (72.9 percent). Survival was comparatively low, being 9.9 percent in acute nonlymphatic leukemia and less than 20 percent in rhabdomyosarcoma and the category grouped as 'other malignant neoplasms.' Survival in Hodgkin's disease was influenced by clinical stage at presentation, but was not statistically significant possibly due to small numbers. 相似文献
30.
Microsystem Technologies - A physics-based Quantum-Modified CLassical Drift–Diffusion (QMCLDD) non-linear mathematical model has been developed for design and characterisation of GaN/AlGaN... 相似文献