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排序方式: 共有261条查询结果,搜索用时 328 毫秒
51.
采用一种新颖的结合信息隐藏技术的语音检索算法,该算法将保密语音和伪语音分割成多段,利用经典的LSB算法分别隐藏到不同的音频,并存储在磁盘空间中.提取语音码流时,利用小波变换第一级细节分量系数能量的大小找到相应的载体音频,提取其中的语音码流,并建立语音库.利用特定人语音检索技术,检出相应的语音码流,合并语音码流得到真正的保密语音.研究表明:新算法的查准率和查全率可以达到很高的水平,为信息隐藏技术的发展开辟了一条新的研究道路,同样扩大了语音检索技术的应用范围。 相似文献
52.
PANG Jie YE Bing-Hong HUANG Yong-Mei LIN Qiong ZENG Cui SUN Yuan-Ming 《结构化学》2007,26(8):924-928
In order to prove up the interaction between konjac glucomannan (KGM) and other amyloses, by using KGM, guaran gum and carrageenan as materials, their blending in different external conditions was modeled by means of molecular dynamics (MD) method. The result showed that 323 K was a significant turning point for the formation of hydrogen bond, and KGM and guaran gum were just juxtaposed together via intermolecular hydrogen bond; but with the addition of carrageenan, KGM, guaran gum and carrageenan were spirally twisted together, and when their blending proportion is 3:2:9 the combination was the most compact. Moreover, the research result has provided the sequent studies afterwards on amyloses with some references. 相似文献
53.
54.
C Premkumar Yesudian 《Pramana》1988,31(3):169-171
The muon events produced at Soudan-I and NUSEX proton decay detectors due to radiation from Cygnus X-3 are given a plausible
explanation on the basis ofE
6 GUT. The possibility of verifying the explanation by using the accelerator experiments is suggested. 相似文献
55.
G. Nienhuis 《Journal of statistical physics》1988,53(1-2):417-438
The statistical properties of the random events that correspond to the emission or the detection of a photon spontaneously emitted by a single atom are discussed. This statistics constitutes a full and nontrivial solution of the stochastic theory of random events. The results are most explicit for an atom with two relevant states. The formalism is also generalized to atomic models with nondegenerate states or with more than one driven transition. 相似文献
56.
In simulation studies, the distributional properties of random variables associated witharbitrary events in point processes, queues, and other stochastic models are to be understood as appropriate averages over long simulation
runs. We caution against trying to generate arbitrary events explicitly by some randomized selection. Because of the likelihood
of hidden selection biases, that easily results in significant errors. The point is illustrated by an example for which explicit
formulas yield computational results that allow comparisons with the simulation estimates.
This work was supported by the Australian Research Council and was done at the ARC Special Research Centre for Ultra-Broadband
Information Networks (CUBIN), Department of Electrical and Electronic Engineering, The University of Melbourne, Victoria 3010,
Australia.
The research of M.F. Neuts was supported in part by NSF Grant Nr. DMI-9988749. 相似文献
57.
58.
I. E. Qureshi M. I. Shahzad S. Manzoor M. S. Zafar H. A. Khan 《Radiation measurements》1997,28(1-6):283-286
One of the main advantages of using dielectric track detectors in the study of heavy ion interactions is the possibility of observing each multi-prong event individually with complete kinematical details. It is thus possible to analyze even those reaction channels that have very low branching ratios. In the study of reactions induced by 16.7 MeV/u uranium ions incident on natural gold targets, we have observed 18 four-pronged events in a total detector area of 24 cm2. Using a polynomial range-energy relationship, empirically fitted to the observed data of binary and ternary events, it was possible to perform kinematical analysis of 10 out of 18 events. The masses and relative velocities of the reaction products, determined in this analysis were compared with theoretical prediction based on double sequential fission process. An agreement within one standard deviation with respect to theoretical values has been found for eight analysed events. 相似文献
59.
Krzysztof Piasecki 《Fuzzy Sets and Systems》1985,17(3):271-284
In this paper the probability of fuzzy events is defined as a denumerable additivity measure. This definition is based on a non-conventional approach of separativity between fuzzy subsets. The presented measure fulfils all properties analogous to the properties of classical probability in the crisp case. Further, the notion of conditional probability of fuzzy events, complete fuzzy repartition and independent fuzzy events are defined by means of the probability measure considered here. Connections between all the above notions are presented in this paper, too. Finally, the Bayes formula is proved for the fuzzy case. 相似文献
60.
Richard F. Serfozo 《Stochastic Processes and their Applications》1985,20(2):281-294
This study shows that when a point process is partitioned into certain uniformly sparse subprocesses, then the subprocesses are asymptotically multivariate Poisson or compound Poisson. Bounds are given for the total-variation distance between the subprocesses and their limits. Several partitioning rules are considered including independent, Markovian, and batch assignments of points. 相似文献