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101.
知识经济时代,人力资源的管理与开发成为企业在激烈的市场竞争中决定成败的关键。然而,由于受到传统文化思想潜移默化的影响和束缚,一些企业的领导者在对待人才的管理、培养和使用上存在误区,导致企业的“核心软件”即人力资源管理不能正常发挥作用。企业领导者应以史为鉴,更新人才管理理念。  相似文献   
102.
A novel segmentation and feedback model (SFM) applied to resolve contention is proposed. Simulation and performance analyses show that the SFM effectively avoids contentions in optical burst switching (OBS). The long delay time of deflection routing and the immature technology of wavelength converters and optical buffers are not deployed in the SFM. The SFM does not only realize fast switching but also allows preemption by higher priority bursts.  相似文献   
103.
Design of photonic crystal fibers for dispersion-related applications   总被引:1,自引:0,他引:1  
A general procedure for design of photonic crystal fibers (PCFs) with desirable dispersion properties is presented. The design model is based on the combination of a rigorous vector mode solver and a scaling transformation for the dispersion properties of the PCFs. In comparison with the conventional design method, the new design procedure is more efficient and can be readily automated for the purpose of design optimization. Several applications of the design procedure, e.g., the design optimization for dispersion shifted fibers, dispersion flattened fibers, and dispersion compensation fibers, are demonstrated and discussed.  相似文献   
104.
Coupling between two collocated orthogonal circular thin-wire loops is analyzed in this paper. Two coupled integral equations for the loop currents are derived and their solution in general form is found in terms of Fourier series. An analytical expression for currents induced through the mutual coupling is obtained for the case when all loop current harmonics higher than first can be ignored. It is found that strong coupling can exist for all loop current harmonics, except for the fundamental. It is also found that coupling for orthogonal collocated loop antennas depends on the relative locations of the loop terminals.  相似文献   
105.
We have developed an easy, low-cost, and low-temperature optoelectronic hermetic packaging technology utilizing the eutectic SnPb solder and the Cr/Ni/Cu bonding pad. Bonding characteristics of the design were investigated in three different setups: silicon-silicon, silicon-glass, and glass-glass samples. Hermeticity was achieved at 200 degC without flux for all samples during the final bonding process. The bonding pads did not dewet during or after the reflow process. By utilizing the eutectic SnPb solder, the self-alignment process can be achieved. Because the bonding process was conducted through visual alignment, original misalignment was estimated to be more than 100 mum. The surface tension of melting solder during the reflow process allowed the samples to self-align and obtain a misalignment of less than 20 mum after solidification, which was 4% of the entire solder width. The bonding strength of the three setups ranged from 3 to 10 MPa. Among the three setups, glass-glass samples appear to have the strongest bonding strength. This low-temperature and cost-effective soldering process has demonstrated its feasibility and potential utilization in optoelectronic packaging  相似文献   
106.
To improve the accuracy of measured gain spectra, which is usually limited by the resolution of the optical spectrum analyzer (OSA), a deconvolution process based on the measured spectrum of a narrow linewidth semiconductor laser is applied in the Fourier transform method. The numerical simulation shows that practical gain spectra can be resumed by the Fourier transform method with the deconvolution process. Taking the OSA resolution to be 0.06, 0.1, and 0.2 nm, the gain-reflectivity product spectra with the difference of about 2% are obtained for a 1550-nm semiconductor laser with the cavity length of 720 /spl mu/m. The spectra obtained by the Fourier transform method without the deconvolution process and the Hakki-Paoli method are presented and compared. The simulation also shows that the Fourier transform method has less sensitivity to noise than the Hakki-Paoli method.  相似文献   
107.
Electromagnetic coupling effects on the antenna in a conducting cavity are studied theoretically and experimentally. It is observed in experiments that at the resonant frequencies of the cavity, the input resistance of the antenna attains values two or three orders of magnitude higher than that at frequencies away from resonance. It is shown via theoretical analysis that the input resistance of the antenna measured at the resonant frequencies of the cavity is not merely the loss resistance desired in computing the antenna efficiency, but is actually the sum of the loss resistance of the antenna and the coupling resistance between the antenna and cavity. This coupling effect is demonstrated quantitatively by numerical computations for dipole and monopole antennas. The computational results for the input resistance are in agreement with the measured data. A method is proposed to avoid the cavity-antenna antiresonance in the measurement.  相似文献   
108.
转动玻璃圆筒激光器   总被引:1,自引:0,他引:1  
本文介绍了转动玻璃圆筒激光器的设计及实验结果,得到了脉冲能量为13J,重复频率为15Hz的激光输出。电光转换效率为2.2%,斜效率为3.4%。  相似文献   
109.
The postbuckling behavior of plates on an elastic foundation is studied by using the boundary element method (BEM). A new fundamental solution of lateral deflection is derived through the resolution theory of a differential operator, and a set of boundary element formulae in incremental form is presented. By using these formulae, the BEM solution procedure becomes relatively simple. The results of a number of numerical examples are compared with existing solutions and good agreement is observed. It shows that the proposed method is effective for solving the postbuckling problems of plates with arbitrary shape and various boundary conditions.  相似文献   
110.
加固改造中的结构承重体系转换   总被引:2,自引:0,他引:2  
从加固改造工程的实践出发 ,探讨了混合结构向框架结构体系转换的方法和构造措施 ,为实际工程提供了新的技术思路  相似文献   
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