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91.
This paper focuses on detecting nuclear weapons on cargo containers using port security screening methods, where the nuclear weapons would presumably be used to attack a target within the United States. This paper provides a linear programming model that simultaneously identifies optimal primary and secondary screening policies in a prescreening-based paradigm, where incoming cargo containers are classified according to their perceived risk. The proposed linear programming model determines how to utilize primary and secondary screening resources in a cargo container screening system given a screening budget, prescreening classifications, and different device costs. Structural properties of the model are examined to shed light on the optimal screening policies. The model is illustrated with a computational example. Sensitivity analysis is performed on the ability of the prescreening in correctly identifying prescreening classifications and secondary screening costs. Results reveal that there are fewer practical differences between the screening policies of the prescreening groups when prescreening is inaccurate. Moreover, devices that can better detect shielded nuclear material have the potential to substantially improve the system’s detection capabilities. 相似文献
92.
93.
本文来自于实际工程应用,在串行通信收发电路中,加LED发光二极管作为收发指示灯时,如果直接驱动LED将会导致通信过程的不可靠甚至不可实现.本文针对该问题进行了分析研究,提出了解决方案,对原电路和改后可靠驱动电路的性能进行了理论分析和计算,并且实际测量了改动前后收发信号的波形,论证了解决方案的可行性. 相似文献
94.
同步静态随机访问存储器常见问题解析 总被引:1,自引:0,他引:1
介绍当今正在大量使用的突发模式SSRAM,零总线反转SSRAM,二倍数据率SSRAM,四倍数据率SSRAM等类器件的差异,澄清一些容易混淆的概念。 相似文献
95.
Scan-in and Scan-out Transition Co-optimization Through Modelling Generalized Serial Transformations
Ozgur Sinanoglu 《Journal of Electronic Testing》2008,24(4):335-351
Scan-based cores impose considerable test power challenges due to excessive switching activity during shift cycles. The consequent
test power constraints force system-on-chip (SOC) designers to sacrifice parallelism among core tests, as exceeding power
thresholds may damage the chip being tested. Reduction of test power for SOC cores can thus increase the number of cores that
can be tested in parallel, improving significantly SOC test application time. In this paper, we propose a scan chain modification
technique that inserts logic gates on the scan path. The consequent beneficial test data transformations are utilized to reduce
the scan chain transitions during shift cycles and hence test power. We introduce a matrix band algebra that models the impact
of logic gate insertion between scan cells on the test stimulus and response transformations realized. As we have successfully
modeled the response transformations as well, the methodology we propose is capable of truly minimizing the overall test power.
The test vectors and responses are analyzed in an intertwined manner, identifying the best possible scan chain modification,
which is realized at minimal area cost. Experimental results justify the efficacy of the proposed methodology as well.
Ozgur Sinanoglu received a B.S. degree in Computer Engineering, and another B.S. degree in Electrical and Electronics Engineering, both from Bogazici University in Turkey in 1999. He earned his M.S. and Ph.D. degrees in the Computer Science and Engineering department of University of California, San Diego, in 2001 and 2004, respectively. Between 2004 and 2006, he worked as a senior design for testability engineer in Qualcomm, located in San Diego, California. Since Fall 2006, he has been a faculty member in the Mathematics and Computer Science Department of Kuwait University. His research field is the design for testability of VLSI circuits. 相似文献
Ozgur SinanogluEmail: |
Ozgur Sinanoglu received a B.S. degree in Computer Engineering, and another B.S. degree in Electrical and Electronics Engineering, both from Bogazici University in Turkey in 1999. He earned his M.S. and Ph.D. degrees in the Computer Science and Engineering department of University of California, San Diego, in 2001 and 2004, respectively. Between 2004 and 2006, he worked as a senior design for testability engineer in Qualcomm, located in San Diego, California. Since Fall 2006, he has been a faculty member in the Mathematics and Computer Science Department of Kuwait University. His research field is the design for testability of VLSI circuits. 相似文献
96.
This study investigates the effect of viewer engagement on gifting items to a streamer in a live video streaming. Data were collected from AfreecaTV, a leading live video streaming platform in South Korea, to examine viewer engagement and gift-giving behavior. After analyzing 2,294,837 viewers over a three-month period, the empirical results provide evidence that viewer engagement is positively associated with gift-giving decisions. However, the impact of viewer engagement on the amount of gifts purchased is different depending on how the engagement is measured (i.e., by stream or by channel). This study empirically proves that the motive for socialization has a high correlation with gift-giving behavior, which is considered as commoditization of a viewer’s social interaction while consuming media. The study concludes with a discussion on practical implications for live video streaming services and suggestions for future research. 相似文献
97.
Fluorescence quenching and synchronous fluorescence methods were used to study the interactions of fluore-scence-active quercetin (Qct) with casein (Cas) and bovine serum albumin (BSA) in phosphate buffer solution (PBS, pH=7.4) with or without coexisting carbon nanotubes (CNTs). Formulae for binding constant (K) and molar binding ratio (n) were established for methods 1 (fixing protein concentration, changing Qct concentration, and monitoring the fluorescence of protein) and 2 (fixing Qct concentration, changing protein concentration, and monitoring the fluorescence of Qct), to which values of K and n were calculated via nonlinear least-square fitting of the experimental data, and the “optical inner filtering induced fluorescence quenching” effect was thus quantitatively evaluated. The quenching effects of coexisting CNTs on the fluorescence of Qct, BSA, and Cas, as well as the effects of coexisting CNTs on Qct-BSA and Qct-Cas interactions, were examined. Synchronous fluorescence was also used to examine the effects of coexisting CNTs and Qct on the conformations of BSA and Cas, with relevant K and n values for tyrosine (Tyr) and tryptophan (Trp) residues estimated. It was concluded that the CNTs mainly interacted with the Trp residues locating near the protein surfaces, but small-sized Qct molecules could further interact with the Tyr residues locating inside the protein molecules. 相似文献
98.
Maurizio DAuria Lucia Emanuele Rocco Racioppi Vincenzina Velluzzi 《Journal of photochemistry and photobiology. A, Chemistry》2008,198(2-3):156-161
The fate of the crude oil under irradiation was studied. After the UV irradiation, the fraction present in the highest percentage shifted from C8–C9 fraction to C13 one, in GC–MS analysis. An increase of the relative amount of the C13–C25 fraction was observed, while a decrease in the relative amount of the C7–C12 fractions was present. The synchronous fluorescence spectrum showed a maximum at 396 nm. Two hours irradiation of the sample induced an increase of the fluorescence emission in the region 420–550 nm. After 20, 40, 60, and 100 h irradiation we observed a decrease of the fluorescence emission. 相似文献
99.
F.?Y.?Kuo W.?T.?M.?DunsmuirEmail author I.?H.?Sloan M.?P.?Wand R.?S.?Womersley 《Methodology and Computing in Applied Probability》2008,10(2):239-275
Highly structured generalised response models, such as generalised linear mixed models and generalised linear models for time
series regression, have become an indispensable vehicle for data analysis and inference in many areas of application. However,
their use in practice is hindered by high-dimensional intractable integrals. Quasi-Monte Carlo (QMC) is a dynamic research
area in the general problem of high-dimensional numerical integration, although its potential for statistical applications
is yet to be fully explored. We survey recent research in QMC, particularly lattice rules, and report on its application to
highly structured generalised response models. New challenges for QMC are identified and new methodologies are developed.
QMC methods are seen to provide significant improvements compared with ordinary Monte Carlo methods.
相似文献
100.
本项目是基于美国TI公司TMS320F28xx系列DSP,进行的测试方法研究与实现。测试方法用于北京自动测试技术研究所自主研发的国产自测试设备(ATE)BC3192V50大规模集成电路测试系统。测试的原理是,通过TMS320F28xx系列DSP配备的SCI(Serial Communication Interface)串行通信接口,以此作为桥梁完成ATE与芯片之间的通信。同时,实现自动测试设备与测试系统的测试向量的匹配。而后,完成TMS320F28xx系列DSP的功能测试以及直流参数测试。 相似文献