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181.
Variation-after-projection (VAP) calculations in conjunction with Hartree-Bogoliubov (HB) ansatz have been carried out for A=100−108 molybdenum (Mo) isotopes. In this framework, the yrast spectra with J max π ≥10+, B(E2) transition probabilities, quadrupole (β2) and hexadecapole (β4) deformation parameters, moment of inertia (I) and square of cranking frequency (ω2) for even-even Mo isotopes have been obtained. The results of the calculation give an indication that it is important to include the hexadecapole-hexadecapole component of the two-body interaction for obtaining various nuclear structure quantities in these Mo isotopes.  相似文献   
182.
The Hartree-Bogoliubov (HB) framework of calculations has been applied for calculating various nuclear structure quantities for 154–166Dy mass chains. In this framework, the intrinsic quadrupole moments, the low-lying yrast states (E 2+ and E 4+) and occupation numbers for various shell model orbits have been obtained. The calculated results indicate that the observed onset of deformation in going from 154Dy to 166Dy arises due to enhanced occupation of (h 11/2)π orbit, increased polarization of (d 5/2)π orbit and increase in the occupation of down-slopping ‘k’ components of (i 13/2)υ and (h 9/2)υ orbits.   相似文献   
183.
In this study, the multi-quasiparticle triaxial projected shell model (TPSM) is applied to investigate \begin{document}$\gamma$\end{document}-vibrational bands in transitional nuclei of \begin{document}$^{118-128}{\rm{Xe}}$\end{document}. We report that each triaxial intrinsic state has a \begin{document}$\gamma$\end{document}-band built on it. The TPSM approach is evaluated by the comparison of TPSM results with available experimental data, which shows a satisfactory agreement. The energy ratios, B(E2) transition rates, and signature splitting of the \begin{document}$\gamma$\end{document}-vibrational band are calculated.  相似文献   
184.
We study the sign of resonances obtained in electromagnetically induced transparency (EIT). Resonances of both kinds—bright (corresponding to enhanced absorption) and dark (corresponding to reduced absorption)—are obtained when the frequency of a probe beam is scanned. The experimental results, presented earlier, use magnetic sublevels of a hyperfine transition in the D1 line of 87Rb along with a magnetic field of 27 G. The atoms are contained in a vapor cell at room temperature, and with anti-relaxation coating on the walls. A quantitative theoretical model, which reproduces the experimental results quite well, is presented for the first time. The model solves the density matrix of the sublevels involved, and uses two regions—one with both the light and magnetic field, and the second without light and just a magnetic field. This ability to have both bright and dark resonances promises applications in sub- and super-luminal propagation of light.  相似文献   
185.
In this paper, an SIS model for bacterial infectious diseases, like tuberculosis, typhoid, etc., caused by direct contact of susceptibles with infectives as well as by bacteria is proposed and analyzed. Here the demography of the human population is constant immigration and the cumulative rate of the environmental discharges is a function of total human population. Further this model is extended to the model for socially structured population (rich and poor) where poor people work as service provider in the houses of rich people but do not settle in the habitat of rich people. It is assumed that bacteria population does not survive in the clean environment of rich people and only affects the population in the degraded environment of the poor class. The stability of the equilibria is studied by using the theory of differential equation and computer simulation. It is concluded that the spread of the infectious disease increases when the growth of bacteria caused by conducive environmental discharge due to human sources increases. Also the spread of the infectious disease in rich class increases due to the interaction with service providers, who are living in relatively poor environmental condition, suggesting the need to keep our environment clean all around.  相似文献   
186.
In this paper, a mathematical model for HILV-I infection of CD4+ T-cells is investigated. The force of infection is assumed be of a function in general form, and the resulting incidence term contains, as special cases, the bilinear and the saturation incidences. The model can be seen as an extension of the model [Wang et al. Mathematical analysis of the global dynamics of a model for HTLV-I infection and ATL progression, Math. Biosci. 179 (2002) 207-217; Song, Li, Global stability and periodic solution of a model for HTLV-I infection and ATL progression, Appl. Math. Comput. 180(1) (2006) 401-410]. Mathematical analysis establishes that the global dynamics of T-cells infection is completely determined by a basic reproduction number R0R0. If R0?1R0?1, the infection-free equilibrium is globally stable; if R0>1R0>1, the unique infected equilibrium is globally stable in the interior of the feasible region.  相似文献   
187.
In the present communication, all-optical clocked J–K flip-flop is proposed and described using silicon waveguide-based optical micro-ring resonator (OMRR). We have used two optical pump signals representing the two operands (J and K) of the logical operation to modulate the OMRRs under low pump power condition. A theoretical model of the proposed J–K flip-flop and hence S–R and T flip-flop are developed using micro-ring resonator through pump–probe configuration. Numerical simulation results for clocked flip-flop circuits verifying the proposed method are given in this paper. We identified a combination of feasible OMRR radius and detuning through numerical simulation which allows analyzing the system performance of the scheme such as maximum amplitude difference between marks \((\hbox {AD}_{1,\mathrm{{max}}})\), between spaces \((\hbox {AD}_{0,\mathrm{{max}}})\) and between marks and spaces \((\hbox {AD}_{1/0,\mathrm{{max}}})\), which confirm the feasibility of the flip-flop design. A maximum buildup factor of 19.57 is achieved at an optimized coupling coefficient of 0.22.  相似文献   
188.
We examined the application of an iterative penalized maximum likelihood (PML) reconstruction method for improved detectability of microcalcifications (MCs) in digital breast tomosynthesis (DBT). Localized receiver operating characteristic (LROC) psychophysical studies with human observers and 2-D image slices were conducted to evaluate the performance of this reconstruction method and to compare its performance against the commonly used Feldkamp FBP algorithm. DBT projections were generated using rigorous computer simulations that included accurate modeling of the noise and detector blur. Acquisition dose levels of 0.7, 1.0, and 1.5 mGy in a 5-cm-thick compressed breast were tested. The defined task was to localize and detect MC clusters consisting of seven MCs. The individual MC diameter was 150 μm. Compressed-breast phantoms derived from CT images of actual mastectomy specimens provided realistic background structures for the detection task. Four observers each read 98 test images for each combination of reconstruction method and acquisition dose. All observers performed better with the PML images than with the FBP images. With the acquisition dose of 0.7 mGy, the average areas under the LROC curve (A(L)) for the PML and FBP algorithms were 0.69 and 0.43, respectively. For the 1.0-mGy dose, the values of A(L) were 0.93 (PML) and 0.7 (FBP), while the 1.5-mGy dose resulted in areas of 1.0 and 0.9, respectively, for the PML and FBP algorithms. A 2-D analysis of variance applied to the individual observer areas showed statistically significant differences (at a significance level of 0.05) between the reconstruction strategies at all three dose levels. There were no significant differences in observer performance for any of the dose levels.  相似文献   
189.

The evaluation of corporate social responsibility (CSR) performance may enhance companies’ willingness to undertake social responsibilities, so it is very important to improve the quality of CSR performance evaluation. Based on the three factors of economic performance, social performance and environmental performance, this paper proposed an improved analytic hierarchy process-back propagation (AHP-BP) neural network algorithm, and introduced the improved AHP-BP neural network algorithm into CSR performance evaluation model. In the stage of improved AHP, the model included the importance of the knowledge and experience of the experts by expert scoring, and reduced the subjective influence of expert judgment on the results by introducing a personality test scale. In the stage of BP neural network, trained models have been used for CSR performance evaluation. The results showed that the prediction result of improved AHP-BP neural network model was better than that of BP neural network model. Therefore, the improved AHP-BP neural network algorithm can be used as a good predictor for CSR performance evaluation.

  相似文献   
190.
Accuracy of sensed data and reliable delivery are the key concerns in addition to several other network‐related issues in wireless sensor networks (WSNs). Early detection of outliers reduces subsequent unwanted transmissions, thus preserving network resources. Recent techniques on outlier detection in WSNs are computationally expensive and based on message exchange. Message exchange‐based techniques incur communication overhead and are less preferred in WSNs. On the other hand, machine learning‐based outlier detection techniques are computationally expensive for resource constraint sensor nodes. The novelty of this paper is that it proposes a simple, non message exchange based, in‐network, real‐time outlier detection algorithm based on Newton's law of gravity. The mechanism is evaluated for its accuracy in detecting outliers, computational cost, and its influence on the network traffic and delay. The outlier detection mechanism resulted in almost 100% detection accuracy. Because the mechanism involves no message exchanges, there is a significant reduction in network traffic, energy consumption and end‐to‐end delay. An extension of the proposed algorithm for transient data sets is proposed, and analytic evaluation justifies that the mechanism is reactive to time series data. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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