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871.
Extant research on high-performance work systems (HPWSs) has primarily examined the effects of HPWSs on establishment or firm-level performance from a management perspective in manufacturing settings. The current study extends this literature by differentiating management and employee perspectives of HPWSs and examining how the two perspectives relate to employee individual performance in the service context. Data collected in three phases from multiple sources involving 292 managers, 830 employees, and 1,772 customers of 91 bank branches revealed significant differences between management and employee perspectives of HPWSs. There were also significant differences in employee perspectives of HPWSs among employees of different employment statuses and among employees of the same status. Further, employee perspective of HPWSs was positively related to individual general service performance through the mediation of employee human capital and perceived organizational support and was positively related to individual knowledge-intensive service performance through the mediation of employee human capital and psychological empowerment. At the same time, management perspective of HPWSs was related to employee human capital and both types of service performance. Finally, a branch's overall knowledge-intensive service performance was positively associated with customer overall satisfaction with the branch's service. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
872.
廖建兴 《电源世界》2013,(4):30-33,29
大功率砖形电源具有体积小,功率密度高,工作环境非常恶劣等特点。本文分析了大功率砖形电源变压器和续流电感的应用环境,给出了相关散热设计方案,以满足大功率通信电源在高温、高压等恶劣条件下的应用要求,最后还给出了铝基板全砖电源优化的实例。  相似文献   
873.
The fault diagnosis schemes are roughly divided into two major categories: signal analysis and modeling method. Compared with the signal analysis approaches, the availability of suitable models of machines could be exploited more conveniently, which allows a more precise and reliable fault identification. In this paper, a modeling fault diagnostic approach based on Volterra series for rotating machinery is presented. After a brief review of the Volterra series theory, the process of the new diagnostic approach and the identification method of Volterra kernels are introduced in detail. The computer simulation verifies its feasibility and validity. Then, this novel method based on Volterra modeling is employed for the fault diagnosis of a rotor-bearing system. Through investigating the changes of generalized frequency response functions of the system under different states, the faults are identified successfully. Finally, the laboratory experimental results verify its effectiveness.  相似文献   
874.
875.
876.
The substitution of Ag for Cu in CuInxGa1?xSe2-based photovoltaic absorber layers can be used to adjust the bandgap energy to better optimize the overall cell efficiency. Based on available thermochemical, equilibrium, and structural data, the Ag-Se system has been assessed and modeled. Given the order-disorder structure transition Ag2Se, the 2- and 3-sublattice models were used to represent the low- and high-temperature phases of the intermetallic compound respectively. Density functional theory based first-principles calculations were used to calculate the Gibbs energy of formation of the end-member compounds. A set of modeling parameters was obtained by the CALculation of PHAse Diagram approach and reasonable agreement was obtained between the experimental thermodynamic properties of the stable phases and the phase relationships in the Ag-Se system.  相似文献   
877.
Radiation dosimeters based on in situ oxygen plasma post-treated diamond thin films were fabricated in a simple sandwich configuration. Effects of deposition process, methane concentration, and in situ oxygen plasma post-treatment on the sensitivity of the devices to X-ray irradiation were investigated. X-ray response demonstrates that the cyclic deposition process could improve response sensitivity. The increase in methane concentration in the deposition gas mixture will worsen the irradiation response of the devices mainly resulted from the change of the orientation and purity of the films. X-ray photoelectron spectroscopy, photoluminescence, and Raman measurements suggest that in situ oxygen plasma post-treatment can effectively etch non-diamond phases and passivate the silicon-vacancy and nitrogen-vacancy defects of the diamond films, resulting in an increase in the sensitivity of the device by a factor of about 2. Time-dependent response to X-ray indicates that the extended period to achieve photocurrent signals stability for the devices is a limitation for promising applications in radiation dosimetry.  相似文献   
878.
In project management, a project can be represented as a network in two ways; namely, activity-on-arc (AoA) and activity-on-node (AoN). Two recent papers have shown that ant colony optimization (ACO) could find critical path(s) in projects represented as AoA networks. This paper points out that the number and placement of logical dummy activities associated with AoA-based networks can pose serious problems. To get around the problems, an ACO technique based on AoN networks is then proposed. For comparison, the two existing AoA-based ACO algorithms were reproduced and modified into AoN-based algorithms. Moreover, the proposed ACO algorithm was applied to AoA networks as well. All six algorithms were tested with several benchmark problems. The test results strongly indicate that AoN-based ACO algorithms are more effective and efficient in finding critical paths than AoA-based algorithms.  相似文献   
879.
By means of the wavelet transform (WT), a power quality (PQ) monitoring system could easily and correctly detect and localize the disturbances in the power systems. However, the signal under investigation is often corrupted by noises, especially the ones with overlapping high-frequency spectrum of the transient signals. The performance of the WT in detecting the disturbance would be greatly degraded, due to the difficulty of distinguishing the noises and the disturbances. To enhance the capability of the WT-based PQ monitoring system, this paper proposes a de-noising approach to detection of transient disturbances in a noisy environment. In the proposed de-noising approach, a threshold of eliminating the influences of noises is determined adaptively according to the background noises. The abilities of the WT in detecting and localizing the disturbances can hence be restored. To test the effectiveness of the developed de-noising scheme, employed were diverse data obtained from the EMTP/ATP programs for the main transient disturbances in the power systems as well as from actual field tests. Using the approach proposed in this paper, remarkable efficiency of monitoring the PQ problems and high tolerance to the noises are approved  相似文献   
880.
Due to the advancement of microoptoelectromechanical systems and microelectromechanical systems (MEMS) technologies, novel display architectures have emerged. One of the most successful and well-known examples is the Digital Micromirror Device from Texas Instruments, a 2-D array of bistable MEMS mirrors, which function as spatial light modulators for the projection display. This concept of employing an array of modulators is also seen in the grating light valve and the interferometric modulator display, where the modulation mechanism is based on optical diffraction and interference, respectively. Along with this trend comes the laser scanning display, which requires a single scanning device with a large scan angle and a high scan frequency. A special example in this category is the retinal scanning display, which is a head-up wearable module that laser-scans the image directly onto the retina. MEMS technologies are also found in other display-related research, such as stereoscopic (3-D) displays and plastic thin-film displays.  相似文献   
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