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91.
Tunisia is one of the Mediterranean countries having windy enough areas, in particular along the coasts. During the past years, Tunisia has embarked upon wind energy programs. The first wind farm in Tunisia was brought into service in January 2000 in the region of Sidi Daoud: it is the first section of the farm that consists of 32 aerogenerators (Made AE-32) of 10.56 MW capacity.In the present study, the wind energy potential of the Sidi Daoud site is statistically analyzed based on 5-year measured hourly time-series wind-speed data (2000–2004). Weibull and Rayleigh parameters at a height of 30 m have been estimated and used to describe the distribution and behavior of annual wind speeds and their frequencies at site.Also, the usable and recoverable energies have been calculated, which are used to determine the energetic and aerodynamic characteristics of aerogenerator Made AE-32 installed on site.The monthly and annual values of use factor (UF) of the first section of Sidi Daoud wind farm have been estimated. 相似文献
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文章的设计是采用内部互联一分二功分器的方法来实现多路功分器,因为实际制作中很难将一分二功分器直接相连,所以在一分二功分器之间需要采用传输线进行连接,本文主要研究了内部互联多路多节功分器的性能以及传输线对内部互联多路多节功分器的影响. 相似文献
94.
优化非致冷红外探测器设计的理论模型 总被引:1,自引:1,他引:1
文章建立了一种改进非致冷红外探测器性能的数学模型,分析了探测器结构和噪声对于噪声等效温差NETD的影响,并给出了NETD与探测器温度TD,背景温度TB,热导G以及探测单元面积A等因素的关系曲线,指出了探测器性能改进和优化的途径. 相似文献
95.
利用SIMS和变温霍尔测量手段对P型Hg0.77Gd0.23Te液相外延材料的Ag掺杂技术、机理及掺杂碲镉汞材料的性能进行了研究。结果表明采用AgNO3溶液直接浸泡方式对该材料进行掺Ag是成功的,掺杂浓度与被掺杂材料中的汞空位浓度是一致的,掺杂后,P型碲镉汞材料的受主能级比掺杂前有明显的减小,从实验结果可看到掺Ag碲镉汞材料的电学性能在室温下保持稳定。 相似文献
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Intelligent methods for automatic protection and restoration are critical in optical transport mesh networks. This paper discusses the problem of quality-of-service (QoS)-based protection in terms of the protection-switching time and availability for end-to-end lightpaths in a WDM mesh network. We analyze the backup lightpath-sharing problem in such networks and study the correlation of the working lightpaths and the impact of the correlation on the sharing of the backup lightpaths. We present a multi-protocol-label-switching (MPLS) control-based fully distributed algorithm to solve the protection problem. The proposed algorithm includes intelligent and automatic procedures to set up, take down, activate, restore, and manage backup lightpaths. It greatly reduces the required resources for protection by allowing the sharing of network resources by multiple backup lightpaths. At the same time, it guarantees, if possible, to satisfy the availability requirement even with resource sharing by taking the correlation of working lightpaths into consideration. A simple analysis of the proposed algorithm in terms of computation time and message complexity indicates that the implementation of the algorithm is practical. The illustrative studies that compare the performance of 1:1, unlimited sharing, and QoS-based backup sharing algorithms indicate that QoS-based sharing achieves comparable performance as unlimited sharing, which is much better than the 1:1 backup scheme in terms of connection blocking probability, average number of connections in the network for a given offered load, and network resource utilization. 相似文献
98.
A nonlinear optical loop mirror (NOLM)-based linear cavity switchable multi-wavelength erbium-doped fiber (EDF) laser is proposed and experimentally demonstrated. Due to the characteristics of the intensity-dependent transmissivity, the NOLM can effectively mitigate the mode competition of the homogenous broadening gain medium, so that the multi-wavelength lasing can be achieved at room temperature. By adjusting the states of the polarization controllers (PCs), the number of the lasing wavelengths in the proposed laser can be adjusted flexibly from 11 to 13 with a wavelength spacing of 0.4 nm around the wavelength of 1 530 nm. 相似文献
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