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151.
Mitsuyoshi Nagao Masahito Yamamoto Keiji Suzuki & Azuma Ohuchi 《International Transactions in Operational Research》2001,8(1):31-45
In this paper, we propose a face identification system based on the Mahalanobis–Taguchi System (MTS). The MTS is one of the pattern recognition methods frequently used in quality engineering, and can perform robust pattern recognition by using training data, including noise. It is likely that this advantage will allow the effective implementation of a robust face identification system against lighting and face position fluctuations. Moreover, the MTS can optimize the number of attributes required for identification by using the orthogonal array and the signal/noise (SN) ratio. The face identification system has to deal with many users and the amount of data in a facial image is large. Therefore, the time required for identification can be decreased and the amount of data in the facial image database can be reduced by performing the optimization. We confirmed the effectiveness of the proposed system through practical experiments. The experimental results revealed that the MTS was an effective method for robust face identification, and could effectively reduce the number of attributes required for identification. 相似文献
152.
A data distribution scheme of sparse arrays on a distributed memory multicomputer, in general, is composed of three phases,
data partition, data distribution, and data compression. To implement the data distribution scheme, many methods proposed
in the literature first perform the data partition phase, then the data distribution phase, followed by the data compression
phase. We called a data distribution scheme with this order as Send Followed Compress (SFC) scheme. In this paper, we propose two other data distribution schemes, Compress Followed Send (CFS) and Encoding-Decoding (ED), for sparse array distribution. In the CFS scheme, the data compression phase is performed before the data distribution phase. In the ED scheme, the data compression phase can be divided into two steps, encoding and decoding. The encoding step and the decoding step are performed before and after the data distribution phase, respectively. To evaluate
the CFS and the ED schemes, we compare them with the SFC scheme. In the data partition phase, the row partition, the column partition, and the 2D mesh partition with/without load-balancing
methods are used for these three schemes. In the compression phase, the CRS/CCS methods are used to compress sparse local arrays for the SFC and the CFS schemes while the encoding/decoding step is used for the ED scheme. Both theoretical analysis and experimental tests were conducted. In the theoretical analysis, we analyze the SFC, the CFS, and the ED schemes in terms of the data distribution time and the data compression time. In experimental tests, we implemented these
three schemes on an IBM SP2 parallel machine. From the experimental results, for most of test cases, the CFS and the ED schemes outperform the SFC scheme. For the CFS and the ED schemes, the ED scheme outperforms the CFS scheme for all test cases.
相似文献
Yeh-Ching ChungEmail: |
153.
154.
155.
S R Rajagopalan 《Bulletin of Materials Science》1983,5(3-4):317-322
The lowest concentration that can be estimated with 100% error in chemical analysis by instrumental technique is referred
to as detection limit. It is equal to the ratio of twice the background signal to the magnitude of analytical signal corresponding
to a concentration of unity. Detection limit (dl) could be improved if the analytical signal alone could be selectively amplified without affecting the background. It is
shown that this could be achieved by chemical amplification. Atomic amplification of two or three orders of magnitude could
be obtained by combining two chemical amplifications in series. It is demonstrated that by using heteropoly acid formation
as the first amplification reaction and determining molybdenum in the heteropoly acid by catalyticdc polarographic wave, a detection limit for the hetero atom of less than a ppb can be obtained. It is pointed out that the
approach of selectively amplifying analytical signals by tandem chemical amplification reactions makes it possible to perform
ultratrace analysis (ppb level) with classical instrumental analytical techniques which havedl at ppm level. 相似文献
156.
该文设计了一种单通道TD-SCDMA射频拉远单元。首先根据系统要达到的性能指标要求,设计了系统拓扑结构,接着从该系统拓扑结构出发,分析了整个系统的设计思路及实现方案,选择相应的电路模块。测试结果表明设计的系统达到了预期的指标,临近通道功率比小于-40.64 dBc和误差向量幅度为5.08%rms。 相似文献
157.
油液的体积弹性模量以及疲劳特性参数是油液非常重要的物理参数,在液压系统中,直接影响系统的稳定性和动态品质.研究设计了弹性模量及疲劳特性参数测试试验台,基于弹性模量的定义对弹性模量进行测量计算,同时以专用车辆油气悬挂装置为对象,对悬挂内液压油疲劳特性参数进行测试,如:温度、粘度等.完成控制系统以及数据采集系统的设计,与上位机实时通讯,实现测试过程的自动化. 相似文献
158.
159.
倪榕生 《南昌工程学院学报》2012,(3):20-23
中频稀土永磁发电机具有功率密度大、体积小、结构简单的特点,以MC68HC908MR32单片机控制为核心的小功率数码中频稀土永磁发电机组,采用"交—直—交"变换,将永磁发电机发出的中频电压变换成单相工频电源电压,样机实测结果表明该机组具有工频电压波形畸变率和电压调整率小、效率高等特点. 相似文献
160.
《Ergonomics》2012,55(12):1175-1183
The effect of caffeine on circulation and metabolism was studied during a discontinuous maximal oxygen uptake (VO2 max) test on a bicycle ergometer. Eight male subjects were chosen for their minimal use of caffeine of which six normally did not ingest caffeinated beverages. Two caffeinated and two decaffeinated (control) trials were administered to each subject following double-blind and counterbalanced testing procedures. One hour before exercise, subjects ingested decaffeinated coffee with or without 350 mg of caffeine anhydrous added. Cardiac output (Q) was measured by a C02 rebreathing technique. Compared to control trials, caffeine increased the VO2 max by an average of 140ml min?1 (p <0-0·5)l. In addition, during caffeine trials, the average maximal heart rate (HR max) was elevated by 5 beats min?1 (p<0·01). There were no other statistically significant changes in metabolic (VO2 and R) and cardiovascular (Q, HR, SV and (a-v) 02 diff) variables during either submaximal or maximal exercise. Performance, as measured by total exercise time on the VO2 max test, was not significantly different (p>0·05). It was concluded that caffeine has a small physiological but a statistically significant effect on VQ2 max and HR max. During submaximal exercise, caffeine did not significantly effect the cardiovascular system. 相似文献