首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   9227篇
  免费   575篇
  国内免费   7篇
电工技术   126篇
综合类   23篇
化学工业   2323篇
金属工艺   288篇
机械仪表   165篇
建筑科学   629篇
矿业工程   99篇
能源动力   322篇
轻工业   647篇
水利工程   52篇
石油天然气   20篇
武器工业   1篇
无线电   748篇
一般工业技术   1895篇
冶金工业   617篇
原子能技术   59篇
自动化技术   1795篇
  2023年   122篇
  2022年   184篇
  2021年   360篇
  2020年   223篇
  2019年   228篇
  2018年   260篇
  2017年   311篇
  2016年   392篇
  2015年   320篇
  2014年   410篇
  2013年   646篇
  2012年   611篇
  2011年   791篇
  2010年   559篇
  2009年   531篇
  2008年   547篇
  2007年   466篇
  2006年   412篇
  2005年   332篇
  2004年   271篇
  2003年   205篇
  2002年   174篇
  2001年   109篇
  2000年   107篇
  1999年   123篇
  1998年   161篇
  1997年   118篇
  1996年   100篇
  1995年   59篇
  1994年   68篇
  1993年   45篇
  1992年   51篇
  1991年   34篇
  1990年   46篇
  1989年   28篇
  1988年   31篇
  1987年   36篇
  1986年   30篇
  1985年   24篇
  1984年   34篇
  1983年   18篇
  1982年   20篇
  1981年   19篇
  1980年   24篇
  1978年   13篇
  1977年   18篇
  1976年   33篇
  1975年   14篇
  1973年   11篇
  1969年   12篇
排序方式: 共有9809条查询结果,搜索用时 562 毫秒
31.
The Na2O-Cs2O-SiO2 system has been investigated by means of a new differential thermal analysis apparatus. Two compounds have been observed for the first time in the metasilicate and disilicate joins. The CsNaSi2O5 disilicate melts congruently at 1217 K and the peritectic fusion of the CsNaSiO3 metasilicate occurs at 1120 K.  相似文献   
32.
In the verified architecture microprocessor (VAMP) project we have designed, functionally verified, and synthesized a processor with full DLX instruction set, delayed branch, Tomasulo scheduler, maskable nested precise interrupts, pipelined fully IEEE compatible dual precision floating point unit with variable latency, and separate instruction and data caches. The verification has been carried out in the theorem proving system PVS. The processor has been implemented on a Xilinx FPGA. A shorter version of this article with the title “Instantiating uninterpreted functional units and memory system: functional verification of the VAMP” appeared in [8]. The work reported here was done while all the authors were with Saarland University.  相似文献   
33.
34.
With increasing globalization, communication across language and cultural boundaries is becoming an essential requirement of doing business, delivering education, and providing public services. Due to the considerable cost of human translation services, only a small fraction of text documents and an even smaller percentage of spoken encounters, such as international meetings and conferences, are translated, with most resorting to the use of a common language (e.g. English) or not taking place at all. Technology may provide a potentially revolutionary way out if real-time, domain-independent, simultaneous speech translation can be realized. In this paper, we present a simultaneous speech translation system based on statistical recognition and translation technology. We discuss the technology, various system improvements and propose mechanisms for user-friendly delivery of the result. Over extensive component and end-to-end system evaluations and comparisons with human translation performance, we conclude that machines can already deliver comprehensible simultaneous translation output. Moreover, while machine performance is affected by recognition errors (and thus can be improved), human performance is limited by the cognitive challenge of performing the task in real time.  相似文献   
35.
The exact magnetization pattern of magnetic films close to a spin-reorientation transition is difficult to analyze due to the intrinsically three-dimensional (3d) variation of the orientation of the local magnetization. We present a technique how this can be performed, based on the analysis of high quality 2d polarization maps from a single scanning electron microscope with polarization analysis (SEMPA) measurement with tilted sample. The key tool is the statistical distribution of all occurring polarization doublets, visualized in a 2d histogram plot. From the shape of the distribution the type of transition—canted-phase, or coexisting phases—can be inferred. For the canted-phase state, the canting angle can be accurately determined from geometrical considerations. With help of the histogram the image data can be analyzed and the three components of the magnetization can be calculated for most points of the image. For a Co/Pt multilayer film we found a cone state. The magnetization forms a complex pattern consisting of out-of-plane domains while the in-plane magnetization shows a maze pattern.  相似文献   
36.
In this paper, a readout circuit for a thickness shear-mode (TSM) resonator is presented which can be used for sensing applications in liquids such as viscosity sensing. The system features compensation of both spurious capacitances and conductances in parallel to the resonator. This allows measurements even in conductive liquids without the need for an elaborate sealing of the sensor. The influence of the spurious elements is determined by means of two orthogonal synchronous detectors and eliminated by active compensation using voltage-controlled amplifiers (VCAs). Furthermore, the circuit is robust against possible phase errors. The basic concept is discussed in detail, and a readout circuit is developed. A prototype is presented, and sample results are given, demonstrating the feasibility of the approach  相似文献   
37.
The present study evaluated the reliability and validity of the Triage Assessment Survey: Organizations (TAS:O), a 27-item, 5-point, Likert summated rating scale. One hundred and seventeen participants responded to the TAS:O after reading mild, moderate, marked and severe organizational crisis scenarios. The overall Cronbach's alpha and split-half reliability were both .93. Confirmatory factor analysis revealed three factors, supporting the hypothesis that the TAS:O is comprised of three distinct factors (i.e., Affect, Behavior, and Cognition). An analysis of variance provided evidence that the TAS:O has the capacity to distinguish among mild, moderate, marked, and severe crises. Because this research is the first to evaluate the TAS:O, further studies are needed to strengthen confidence in the psychometric properties of this scale.  相似文献   
38.
39.
The European Space Agency ESA aims at minimizing the safety risks of their space flight projects. Hazard and risk reduction is supported by hazard analysis and probabilistic risk assessment. In hazard analysis hazardous conditions and accident scenarios are identified. Risk assessment is the probabilistic evaluation of accident scenarios and is the basis for risk management. The risk assessment method involves the determination and propagation of event probability. Expert judgement is used in a structured way. In risk management the risk assessment results are used to prioritize and optimize risk reduction efforts and to support risk acceptance evaluations.  相似文献   
40.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号