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61.
A big yield drop has been observed during the automatic inspection (AOI) after the saw stage. A step by step AOI inspection check and defect review is made to see which step made a big yield drop and which kind of defect contributed most to the yield drop. Scanning electron microscope (SEM) and energy dispersive spectrometer (EDS) analysis showed the shape and chemical element of the particle. From the EDS result, particles can be separated into two categories. One was the inorganic related materials, mainly including silicon (Si) element, which came from the saw stage. A design of experiment (DOE) is used to find some reasonable saw relative parameter and optimize it in order to remove the particle from the saw stage. But the quantity of this kind of particle was small. Yield was only improved by less than 5%. Our main effort was to remove another kind of particle which was organic related materials, mainly including carbon (C) and oxygen (O) element. This kind of particle was from tape residue. In order to remove the tape residual, one step was added before the saw stage. Almost all of the tape residual was removed. Finally, the final yield was improved by more than 15%. 相似文献
62.
A systematic efficient fault diagnosis method for reconfigurable VLSI/WSI array architectures is presented. The basic idea is to utilize the output data path independence among a subset of processing elements (PEs) based on the topology of the array under test. The divide and conquer technique is applied to reduce the complexity of test application and enhance the controllability and observability of a processor array. The array under test is divided into nonoverlapping diagnosis blocks. Those PEs in the same diagnosis block can be diagnosed concurrently. The problem of finding diagnosis blocks is shown equivalent to a generalizedEight Queens problem. Three types of PEs and one type of switches, which are designed to be easily testable and reconfigurable, are used to show how to apply this approach. The main contribution of this paper is an efficient switch and link testing procedure, and a novel PE fault diagnosis approach which can speed up the testing by at leastO(V1/2) for the processor arrays considered in this paper, where V is the number of PEs. The significance of our approach is the ability to detect as well as to locate multiple PE, switch, and link faults with little or no hardware overhead. 相似文献
63.
64.
Fault diagnosis of full-scan designs has been progressed significantly. However, most existing techniques are aimed at a logic
block with a single fault. Strategies on top of these block-level techniques are needed in order to successfully diagnose
a large chip with multiple faults. In this paper, we present such a strategy. Our strategy is effective in identifying more
than one fault accurately. It proceeds in two phases. In the first phase we concentrate on the identification of the so-called
structurally independent faults based on a concept referred to as word-level prime candidate, while in the second phase we further trace the locations of the more elusive structural dependent faults. Experimental results
show that this strategy is able to find 3 to 4 faults within 10 signal inspections for three real-life designs randomly injected
with 5 node-type or stuck-at faults.
Part of this work has ever appeared in the proceedings of Asian Test Symposium in 2003.
Yu-Chiun Lin received his BS degrees in Electrical Engineering from National Central University in 2000, and MS degree from Electrical
Engineering of National Tsing Hua University in 2002. Since then, he has been with Ali Corporation as a design engineer. His
current interests include the design of USB controllers and imaging periperals.
Shi-Yu Huang received his BS, MS degrees in Electrical Engineering from National Taiwan University in 1988, 1992 and Ph.D. degree in Electrical
and Computer Engineering from the University of California, Santa Barbara in 1997, respectively. From 1997 to 1998 he was
a software engineer at National Semiconductor Corp., Santa Clara, investigating the System-On-Chip design methodology. From
1998 to 1999, he was with Worldwide Semiconductor Manufacturing Corp., designing the high-speed Built-In Self-Test circuits
for memories. He joined the faculty of National Tsing-Hua University, Taiwan, in 1999, where he is currently an Associate
Professor. Dr. Huang’s research interests include CMOS image sensor design, low-power memory design, power estimation, and
fault diagnosis methodologies. 相似文献
65.
The results are reported of a detailed investigation into the photoinduced changes that occur in the capacitance–voltage (C–V) response of an organic metal–insulator–semiconductor (MIS) capacitor based on the organic semiconductor poly(3-hexylthiophene), P3HT. During the forward voltage sweep, the device is driven into deep depletion but stabilizes at a voltage-independent minimum capacitance, Cmin, whose value depends on photon energy, light intensity and voltage ramp rate. On reversing the voltage sweep, strong hysteresis is observed owing to a positive shift in the flatband voltage, VFB, of the device. A theoretical quasi-static model is developed in which it is assumed that electrons photogenerated in the semiconductor depletion region escape geminate recombination following the Onsager model. These electrons then drift to the P3HT/insulator interface where they become deeply trapped thus effecting a positive shift in VFB. By choosing appropriate values for the only disposable parameter in the model, an excellent fit is obtained to the experimental Cmin, from which we extract values for the zero-field quantum yield of photoelectrons in P3HT that are of similar magnitude, 10?5 to 10?3, to those previously deduced for π-conjugated polymers from photoconduction measurements. From the observed hysteresis we deduce that the interfacial electron trap density probably exceeds 1016 m?2. Evidence is presented suggesting that the ratio of free to trapped electrons at the interface depends on the insulator used for fabricating the device. 相似文献
66.
恰当选择原材料、确保铆接工序质量、重视工作电解液的配比、严控各工序成品率是提高超小型铝电解电容器投入产出一次合格率的关键。以10V-47μF(4mm×7mm)产品为例,投入产出一次合格率达94%以上。 相似文献
67.
球形触点阵列(BGA)封装技术作为一种新的封装技术越来越受到人们的重视。从安装率和成本、表面安装印制板设计以及焊点可靠性三个方面对球形触点阵列与四边扁平封装(QFP)进行了比较。分析认为,BGA和QFP各有其优势和劣势,各有其应用重点。 相似文献
68.
随着我国城市化进程的快速推进和海绵城市理念的不断加深,低影响开发(LID)措施日益受到各地重视。为评估LID措施的雨洪控制效果,构建基于SWMM的东濠涌流域城市雨洪模型,分析选取适合该研究区域的LID措施,分别采用重现期为0.5、1、2、5、10年的设计降雨对LID措施的雨洪控制效应进行分析。研究结果表明:LID措施能够较为有效地减小流域洪峰流量、径流量及推迟峰值时间,对初期雨水径流污染负荷也具有较好的削减作用,且径流量和污染物削减率均随着重现期增大而减小。 相似文献
69.
70.
考察了降低焦炭塔操作压力对延迟焦化过程的影响。中试结果表明:在炉出口温度、注汽量、循环比等操作条件基本一致的情况下,当焦炭塔的操作压力由0.195MPa降低到0.115MPa时,气体和焦炭的产率降低,液体产品收率提高且表现在焦化蜡油收率的提高上,二者分别提高了2.03百分点和4.64百分点;随着操作压力的降低,焦化汽油和焦化柴油的性质基本一致,但焦化蜡油性质变差,主要表现在密度、残炭、沥青质、氮含量及金属等均有所升高,95%馏出温度提高14℃;石油焦的挥发分呈降低趋势。 相似文献