全文获取类型
收费全文 | 65篇 |
免费 | 0篇 |
专业分类
电工技术 | 1篇 |
化学工业 | 5篇 |
金属工艺 | 1篇 |
机械仪表 | 1篇 |
轻工业 | 1篇 |
无线电 | 45篇 |
一般工业技术 | 3篇 |
冶金工业 | 7篇 |
自动化技术 | 1篇 |
出版年
2016年 | 1篇 |
2014年 | 1篇 |
2013年 | 1篇 |
2012年 | 1篇 |
2006年 | 1篇 |
2004年 | 1篇 |
2003年 | 1篇 |
2002年 | 1篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1998年 | 5篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 2篇 |
1994年 | 6篇 |
1993年 | 6篇 |
1992年 | 2篇 |
1991年 | 3篇 |
1990年 | 4篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1983年 | 1篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1973年 | 1篇 |
1971年 | 2篇 |
1970年 | 2篇 |
1969年 | 1篇 |
1968年 | 3篇 |
排序方式: 共有65条查询结果,搜索用时 15 毫秒
1.
There is often a need to approximate integrals of highly oscillatory functions when studying scattering and diffraction of electromagnetic waves. This paper presents a method of estimating certain types of these integrals by evaluating one interpolating function and performing one or two relatively easy numerical integrations. The method is demonstrated for the case of a Fresnel integral 相似文献
2.
Adult image recognition is an important technique for preventing children from accessing offensive material on the Internet. Most of the related works focus on single image recognition. However, adult images usually exist as a group and rarely stand alone. Therefore, considering the entire image group as a whole for classification should be more effective. This paper presents a new method of detecting adult image groups, which aims at achieving optimal recognition accuracy. Adult image group recognition generally includes two components: an adult image recogniser and a final decision rule for classifying the image group. We provide a theoretical analysis to clarify the correlation of the two components and use probability formulae to estimate the recognition rates for different settings of the adult image recogniser and the decision rule. Then, a set of optimal receiver-operating characteristic (ROC) curves for different image numbers is solved. To recognise an unknown image group, a desired recall rate for adult (or benign) image groups is specified and the system is set according to the parameters acquired from the optimal ROC curves. The proposed method can be dynamically adapted to the recall rates that the user expects. This advantage makes the proposed system more suitable for real applications. Our work can be viewed as an extension of single image recognition and the experimental results demonstrate that it can attain higher recognition accuracy than the earlier methods. 相似文献
3.
Nyquist RM Ataka K Heberle J 《Chembiochem : a European journal of chemical biology》2004,5(4):431-436
The catalytic action of membrane proteins is vital to many cellular processes. Yet the molecular mechanisms remain poorly understood. We describe here the technique of evanescent infrared difference spectroscopy as a tool to decipher the structural changes associated with the enzymatic action of membrane proteins. Functional changes as minute as the protonation state of individual amino acid side chains can be observed and linked to interactions with a ligand, agonist, effector, or redox partner. 相似文献
4.
A mixed potential formulation is given for electrical fields in layered environments. Contributions to the field from charges are identified explicitly through a scalar Green's function for layered media. The outcome is a computationally expedient Sommerfeld integral representation 相似文献
5.
Radar target discrimination using the extinction-pulse technique 总被引:9,自引:0,他引:9
Rothwell E. Nyquist D. Kun-Mu Chen Drachman B. 《Antennas and Propagation, IEEE Transactions on》1985,33(9):929-937
An aspect independent radar target discrimination scheme based on the natural frequencies of the target is considered. An extinction-pulse waveform upon excitation of a particular conducting target results in the elimination of specified natural modal content of the scattered field. Excitation of a dissimilar target produces a noticeably different late-time response. Construction of appropriate extinction-pulse waveforms is discussed, as well as the effects of random noise on their application to thin cylinder targets. Also presented is experimental verification of this discrimination concept using simplified aircraft models. 相似文献
6.
Drachman B. Cloud M. Nyquist D.P. 《Antennas and Propagation, IEEE Transactions on》1989,37(3):403-406
It is shown that the fast Fourier transform (FFT) combines naturally with Simpson's rule for Sommerfeld-type integral computation. The principal advantage of using the FFT is that a single subroutine call yields a set of sample values of an integral (i.e. the integral for various values of an integrand parameter). Such samples could be useful in themselves. In other applications Sommerfeld integrals represent Green's functions nested within other spatial integrals, so samples from the FFT might be useful in approximating the outernested integral. Several examples are provided to illustrate the process 相似文献
7.
Frequency domain E-pulse synthesis and target discrimination 总被引:8,自引:0,他引:8
Rothwell E. Kun-Mu Chen Nyquist D. Weimin Sun 《Antennas and Propagation, IEEE Transactions on》1987,35(4):426-434
A frequency domain approach to theE -pulse radar target discrimination scheme is introduced. This approach is shown to allow easier interpretation ofE -pulse convolutions via theE -pulse spectrum, and leads to a simplified calculation of pulse basis function amplitudes in theE -pulse expansion. Experimental evidence obtained using aircraft models verifies the single-mode discrimination scheme, as well as the aspect-independent nature of theE -pulse technique. This leads to an integrated technique for target discrimination combining theE -pulse with single mode extraction waveforms. 相似文献
8.
Chen K.M. Nyquist D.P. Rothwell E.J. Sun W.M. 《Antennas and Propagation, IEEE Transactions on》1992,40(7):829-833
Experimental results obtained using the ground-plane time-domain scattering ranges are presented. An experimental demonstration of the noise-insensitivity of the E/S pulse technique is also presented 相似文献
9.
Stenholm G.J. Rothwell E.J. Nyquist D.P. Kempel L.C. Frasch L.L. 《Antennas and Propagation, IEEE Transactions on》2003,51(12):3221-3227
The feasibility of using the E-pulse technique to diagnose changes in the properties of simple layered materials is undertaken. Numerical results for a conductor-backed lossy slab and a Salisbury screen show that changes in permittivity, conductivity and thickness can be diagnosed in the presence of white Gaussian noise. 相似文献
10.
David A. Nyquist 《Lipids》1988,23(10):989-992
Thiophosphoester analogs of dioctanoyl and didecanoyl phosphatidic acids were synthesized for use as substrates in spectrophotometric
assays. These substrates are easily dispersable in aqueous media and release thiodiacylglycerols after phosphomonoesterase
catalyzed hydrolysis. The free sulfhydryl of these thiodiacylglycerols reacts with the colorimetric reagent 5,5′-dithiobis(2-nitrobenzoic
acid) (DTNB), allowing the reaction to be followed. These analogs were shown to be good substrates for calf intestine alkaline
phosphatase (highest activity at alkaline pH) and phosphomonoesterases of partially purified beef brain cytosol (highest activity
at physiologic pH). Cationic amphiphilic drugs inhibit the actions of alkaline phosphatase on the dioctanoyl analog, but did
not inhibit enzymatic hydrolysis ofp-nitrophenyl phosphate. In contrast, the beef brain cytosolic fractionp-nitrophenyl phosphate hydrolysis was mildly inhibited, and the phosphatidic acid analog hydrolysis was increased slightly.
Tetramisole inhibited all enzyme activities withp-nitrophenyl phosphate, but was inhibitory only to the alkaline-phosphatase activity with the phosphatidic acid analog.
This research was completed as partial fulfillment of the Ph.D. degree, awarded August, 1987, at Northern Illinois University,
DeKalb, IL. 相似文献