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101.
As μ-TAS (micro total analysis system) is developed with enhancement of MEMS technology, the growth of medical and biological research areas increases rapidly. The study on LOC (lab on a chip), which is one of the μ-TAS and has the functions of mixing and analyzing with a tiny amount of sample and reagent on one chip, is actively progressed. LOC is composed of the microfluidic components such as micromixers and micropumps. Because the flow on the microfluidic system is generally laminar, it is very difficult to mix and feed fluidic reagents efficiently. This paper presents the design and the fabrication of the MHD micropump with mixing function, in which the fluids are simultaneously mixed and pumped by coupling between Lorentz force and the moving force of an electric charge in the electric field. The advanced model was determined through the commercial CFD program after several models were modified. The numerical results have been compared with the experimental results. This study shows the proposed micropump can be made through simple fabrication procedure and has the low energy consumption. 相似文献
102.
Autonomous topological modeling of a home environment and topological localization using a sonar grid map 总被引:1,自引:0,他引:1
This paper presents a method of autonomous topological modeling and localization in a home environment using only low-cost
sonar sensors. The topological model is extracted from a grid map using cell decomposition and normalized graph cut. The autonomous
topological modeling involves the incremental extraction of a subregion without predefining the number of subregions. A method
of topological localization based on this topological model is proposed wherein a current local grid map is compared with
the original grid map. The localization is accomplished by obtaining a node probability from a relative motion model and rotational
invariant grid-map matching. The proposed method extracts a well-structured topological model of the environment, and the
localization provides reliable node probability even when presented with sparse and uncertain sonar data. Experimental results
demonstrate the performance of the proposed topological modeling and localization in a real home environment. 相似文献
103.
This paper describes the design and fabrication of a MEMS guide plate, which was used for a vertical probe card to test a
wafer level packaged die wafer. The size of the fabricated MEMS guide plate was 10.6 × 10.6 cm. The MEMS guide plate consisted
of 8,192 holes to insert pogo pins, and four holes for bolting between the guide plate and the housing. To insert pogo pins
easily, an inclined plane was defined at the back of each hole. Pitch and diameter of the hole were 650 and 260 μm, respectively.
In order to define inserting holes and inclined planes at an exact position, silicon MEMS technology was used such as anisotropic
etching, deep reactive etching and more. Silicon was used as the material of the guide plate to reduce alignment mismatch
between the pogo pins and solder bumps during a high temperature testing. A combined probe card with the fabricated MEMS guide
plate showed good x–y alignment and planarity errors within ±9 and ±10 μm at room temperature, respectively. In addition, x–y alignment and planarity are ±20 and ±16 μm at 125°C, respectively. The proposed MEMS guide plate can be applied to a vertical
probe card for burn-in testing of a wafer level packaged die wafer because the thermal expansion coefficient of the MEMS guide
plate and die wafer is same. 相似文献
104.
105.
Yong Suk Choi 《Knowledge》2011,24(8):1139-1150
Recently, due to the widespread on-line availability of syntactically annotated text corpora, some automated tools for searching in such text corpora have gained great attention. Generally, those conventional corpus search tools use a decomposition-matching-merging method based on relational predicates for matching a tree pattern query to the desired parts of text corpora. Thus, their query formulation and expressivity are often complicated due to poorly understood query formalisms, and their searching tasks may require a big computational overhead due to a large number of repeated trials of matching tree patterns. To overcome these difficulties, we present TPEMatcher, a tool for searching in parsed text corpora. TPEMatcher provides not only an efficient way of query formulation and searching but also a good query expressivity based on concise syntax and semantics of tree pattern query. We also demonstrate that TPEMatcher can be effectively used for a text mining in practice with its useful interface providing in-depth details of search results. 相似文献
106.
Surface texture is one of the important properties for the human to identify objects by touch. Effective reconstructions of
textures are necessary for realistic interactions between the human and environment via human–computer interfaces. This paper
presents a systematic approach for sensing and reconstructing periodic surface textures. Three significant issues are discussed:
a pen-type texture sensor that measures the spatial information based on the measurements of contact forces; an algorithm
for the reconstruction of periodic textures based on the obtained spatial information; and the method of incremental scanning
to identify the polar spectrum of a surface by limited number of scans. The concept of polar spectrum is introduced to describe
the spatial properties of the surface, that is, the relation between spatial frequencies and the direction of measurement.
The pattern of polar spectrum is used to facilitate surface reconstructions. Experimental results based on the spatial information
obtained with a laser displacement sensor and the pen-type texture sensor demonstrate the effectiveness of the proposed methods
for the measurement and reconstruction of periodic textures. 相似文献
107.
Myung Geol Choi Eunjung Ju Jung‐Woo Chang Jehee Lee Young J. Kim 《Computer Graphics Forum》2009,28(7):1773-1780
The standard C/C++ implementation of a spatial partitioning data structure, such as octree and quadtree, is often inefficient in terms of storage requirements particularly when the memory overhead for maintaining parent‐to‐child pointers is significant with respect to the amount of actual data in each tree node. In this work, we present a novel data structure that implements uniform spatial partitioning without storing explicit parent‐to‐child pointer links. Our linkless tree encodes the storage locations of subdivided nodes using perfect hashing while retaining important properties of uniform spatial partitioning trees, such as coarse‐to‐fine hierarchical representation, efficient storage usage, and efficient random accessibility. We demonstrate the performance of our linkless trees using image compression and path planning examples. 相似文献
108.
We present a secure routing protocol that is immune to Sybil attacks and that can tolerate collusion of Byzantine routers. It can tolerate either initial collusion of Byzantine routers or runtime collusion of non-adjacent Byzantine routers, both in the absence of runtime collusion between adjacent routers. For these settings, the calculated distance from a destination to a node is not smaller than the actual shortest distance from the destination to the node. The protocol can also simultaneously tolerate initial collusion of Byzantine routers and runtime collusion of adjacent Byzantine routers but in the absence of runtime collusion between non-adjacent routers. For this setting, it guarantees a bound on the difference between the calculated distance and the actual shortest distance. The bound depends on the number of Byzantine routers on a path. The protocol makes very weak timing assumptions and requires synchronization only between neighbors or second neighbors. We propose to use this protocol for secure localization of routers using hop-count distances, which can be then used as a proof of identity of nodes. 相似文献
109.
110.