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321.
Manoj Sachdev 《Journal of Electronic Testing》1995,6(3):265-276
Owing to the non-binary nature of their operation, analog circuits are influenced by process defects in a different manner compared to digital circuits. This calls for a careful investigation into the occurrence of defects in analog circuits, their modeling related aspects and their detection strategies. In this article, we demonstrate with the help of a real CMOS circuit that simple test stimuli, like DC, transient and AC, can detect most of the modeled process defects. Silicon devices tested with the proposed test methodology demonstrate the effectiveness of the method. Subsequently, the proposed test method is implemented in production test environment along with the conventional test for a comparative study. This test methodology is structured and simpler, therefore results in substantial test cost reduction. 相似文献
322.
In the absence of information about the layout one is left with no alternative but to consider all bridging faults. An algorithm for diagnosis of a subset of such faults, viz. single two line bridging faults in static CMOS combinational circuits is presented. This algorithm uses results from I
DDQ
measurement based testing.Unlike known diagnosis algorithms, this algorithm does not use fault dictionaries, it uses only logic simulation and uses no fault simulation. It also uses SOPS, a novel representation of subsets of two-line bridging faults resulting in an efficient algorithm.In spite of the large number of faults that we consider, our experimental results point to the computational feasibility of I
DDQ
Measurement based diagnosis of single two line bridging faults. It also shows the effectiveness of reducing the set of possible faults using I
DDQ
measurements.A preliminary version of this work was presented at the 29th ACM/IEEE Design Automation Conference, 1992.Research Partially Supported by NSF Grant No. MIP-9102509.This work was performed when the author was with the Dept. of Computer Science, State University of New York at Buffalo. 相似文献
323.
324.
Alberto Ferrer Daniel Aguado Santiago Vidal‐Puig José Manuel Prats Manuel Zarzo 《商业与工业应用随机模型》2008,24(6):551-567
Modern industrial processes are characterized by acquiring massive amounts of highly collinear data. In this context, partial least‐squares (PLS) regression, if wisely used, can become a strategic tool for process improvement and optimization. In this paper we illustrate the versatility of this technique through several real case studies that basically differ in the structure of the X matrix (process variables) and Y matrix (response parameters). By using the PLS approach, the results show that it is possible to build predictive models (soft sensors) for monitoring the performance of a wastewater treatment plant, to help in the diagnosis of a complex batch polymerization process, to develop an automatic classifier based on image data, or to assist in the empirical model building of a continuous polymerization process. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
325.
It is often stated that in irredundant two-level logic circuits, a test set for all single stuck faults will also detect all multiple stuck faults. We show by a simple example that this result does not hold for multi-output circuits even when each output function is prime and irredundant. Using a result from the programmable logic array technology, we give an output ordering constraint that, if satisfied during test generation, will make a single stuck fault test set a valid multiple stuck fault test set for irredundant two-level multi-output circuits. 相似文献
326.
Roger Perry 《Journal of Electronic Testing》1992,3(4):317-325
I
DDQ
testing with precision measurement unit (PMU) was used to eliminate early life failures caused by CMOS digital ASICs in our products. Failure analysis of the rejected parts found that bridging faults caused by particles were not detected in incoming tests created by automatic test generation (ATG) for stuck-at-faults (SAF). The nominal 99.6% SAF test coverage required to release a design for production was not enough! This article shows how I
DDQ
testing and supplier process improvements affected our early life failure rates over a three year period. A typical I
DDQ
measurement distribution, effects of multiple I
DDQ
testing, and examples of the defects found are presented. The effects of less than 99.6% fault coverage after the I
DDQ
testing was implemented are reviewed. The methods used to establish I
DDQ
test limits and implement the I
DDQ
test with existing ATG testing are included. This article is a revision of one given at International Test Conference [1]. 相似文献
327.
随着半导体工业的迅速发展,印刷电路板(PCB)故障的检测和诊断已经成国PCB制造过程中的一个核心问题。本文介绍了红外热成象技术(IIT)检测PCB故障的原理。详细分析了IIT对各种PCB故障的检测和诊断能力,并与传统的自动测试设备(ATE)作了比较。由于IIT检测的非接触性和直观性,IIT可望成为PCB制造中一 有效的质量保证手段。 相似文献
328.
329.
Masakazu Katsuno Noboru Ohtani Tatsuo Fujimoto Hirokatsu Yashiro 《Journal of Electronic Materials》2005,34(1):91-95
The effect of off-orientation growth has been investigated in terms of stacking fault formation during physical vapor transport
(PVT) growth of silicon carbide (SiC) single crystals on the (11
0) seed crystal surface. Occurrence of stacking fault formation is largely dependent on the direction of off-orientation,
and basal plane stacking fault density is significantly reduced by growing the crystals on a (11
0) seed crystal off-oriented toward 〈0001〉. The density of the basal plane stacking faults rapidly decreases from 100–150
cm−1 to ∼10 cm−1 as the degree of off-orientation is increased from 0 to 10 deg. The results are interpreted in the framework of microscopic
facet formation during PVT growth, and the introduction of off-orientation of seed crystal is assumed to prevent (01
0) and (10
0) microfacet formation on the (11
0) growing surface through modification of the surface growth kinetics and to suppress the stacking fault formation.
An erratum to this article is available at . 相似文献
330.