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41.
设计并研制成功适合人的眼睛安全测距应用的InGaAs雪崩光电二极管(APD)。器件直径为200μm,工作在21℃,1540nm波长时响应为0.64A/W,典型暗电流和噪声因子分别为30nA和6.5。介绍了该器件的工作原理,设计和制作工艺。 相似文献
42.
Spaces without northerly orientations have an impact on the ‘energy behaviour’ of a building. This paper outlines possible energy savings and better performance achieved by different zenithal solar passive strategies (skylights, roof monitors and clerestory roof windows) and element arrangements across the roof in zones of cold to temperate climates typical of the central and central-southern Argentina. Analyses were undertaken considering daylighting, thermal and ventilation performances of the different strategies. The results indicate that heating, ventilation and lighting loads in spaces without an equator-facing facade can be significantly reduced by implementing solar passive strategies. In the thermal aspect, the solar saving fraction reached for the different strategies were averaged 43.16% for clerestories, 41.4% for roof monitors and 38.86% for skylights for a glass area of 9% to the floor area. The results also indicate average illuminance levels above 500 lux for the different clerestory and monitor arrangements, uniformity ratios of 0.66–0.82 for the most distributed arrangements and daylighting factors between 11.78 and 20.30% for clear sky conditions, depending on the strategy. In addition, minimum air changes rates of 4 were reached for the most extreme conditions. 相似文献
43.
This paper presents an efficient method which provides the optimal generation mix and the optimal generation construction process. The approximation method in which the dynamic programming technique and gradient method are combined is applied to determine the optimal generation mix with hydropower generation technologies. The successive approximations dynamic programming (SADP) technique, which is very suitable for high-dimensional multistage decision process problems, is used for obtaining the optimal generation construction process. The effectiveness and feasibility of the developed technique are demonstrated on a practical power system model which has five types of generation technologies including a hydropower generation technology. 相似文献
44.
核电厂操作人员心理特质的定量研究 总被引:2,自引:0,他引:2
在介绍前苏联Prognoz心理研究所和我国台湾省我国内外有关心理特质定量测试研究基础上,介绍了对我国核电厂操作人员运用美国明尼苏达多项个性测试(MMP)进行心理特质分析的初步结果,提出了开展我国核电厂操作人员心理物质研究了主要内容,并强调了进行核电厂操作人员心理物质选拔和心理培训的必要性。 相似文献
45.
电源对介质阻挡放电(DBD)激发准分子(XeCl*)辐射的影响 总被引:3,自引:2,他引:1
本文对电源参数如电压幅值、频率及正负电压对介质阻挡放电激发准分子XeCl 紫外 (30 8nm)辐射的影响进行了实验研究。结果表明 ,UV辐射随电压幅度的增加而增强 ,但效率下降 ;提高频率 ,增加了放电次数 ,导致UV辐射的增强 ;此外 ,在较高的频率下 ,电压上升沿变陡 ,使得电子获得的能量主要用于原子的激发和电离。正、负电压放电的不对称源于电极结构的不对称而引起的放电过程的差异 ,负电压内电极可向放电管中馈入更多的能量 ;比较发光光谱可判断生成准分子的等离子体化学过程没有明显的差别 相似文献
46.
Influence of pH on the passivation behavior of 254SMO stainless steel in 3.5% NaCl solution 总被引:1,自引:0,他引:1
C.T. Liu 《Corrosion Science》2007,49(5):2198-2209
The potentiodynamic polarization measurement of 254SMO stainless steel (UNS 31254) was conducted in 3.5% NaCl solutions with pH ranging from 0.1 to 5. The results indicated that this stainless steel offered excellent pitting corrosion resistance in corrosive environments. Further, it also exhibited various features on the polarization curves in different pH solutions. The electrochemical constant-potential passivation treatment performed at different pH followed by XPS analysis revealed that the primary constituents of the outermost layer of the passive films formed in the weak (pH 5) and strong (pH 0.8) acid solutions are iron oxides and Cr2O3 and Cr(OH)3, respectively. Molybdenum oxides, primarily in the six-valence state, existed in the outermost layer of the passive film. Only very weak signals corresponding to that of nickel oxides were detected in the film formed in the weak acid (pH 5) solution. The ICP-MS analyses indicated selective dissolution of a significant amount of Fe and a few Mo and Ni ions during the passivation treatment in the strong acid (pH 0.8) solution. No Cr dissolution was observed; this indicated that the Cr in the film is relatively stable. XPS depth profiling results showed that a similar bilayer-structured film was formed in both the solutions (pH 0.8 and 5); the outer layer of this film is primarily composed of Cr(OH)3 and Mo(VI), and the inner layer, Cr2O3 and Mo(IV). The results of the examinations of passive film formations and dissolution by XPS and ICP-MS were consistent with the polarization curves. 相似文献
47.
Ricardo Lima Author Vitae Author Vitae Claudio Reineri Author Vitae Author Vitae 《Computers & Electrical Engineering》2008,34(6):520-530
This paper presents a novel concept for power quality hardware and software architecture. Software tools related to detection, classification and characterization of power quality events can be integrated into a Distribution Control Center in which the interconnection between different subsystems is being carried out through the Internet allowing flexibility to the system. This system is implemented using wavelet analysis applied in all proposed algorithms. Different power quality events are taken as examples to illustrate the capabilities of the proposed method. The obtained results reveal that the proposed architecture is feasible to be implemented as an integral part of a control center system.The proposed system has the property of fast and accurate detection and classification of any power quality disturbance event and introduces a new PQ index determination that allows characterizing any type of disturbance including the non-periodic signals. 相似文献
48.
房间空调器高效节能技术分析 总被引:2,自引:0,他引:2
周彬 《制冷与空调(北京)》2003,3(4):44-46
本文主要介绍了高效节能型空调器的优化设计,包括选用高效压缩机、增大换热面积,增大风量、管路的合理设计,旨在提高制冷量,降低功耗,提高能效比。 相似文献
49.
大型水轮发电机组励磁变压器参数及绝缘方式的选择--由三峡机组励磁系统投运引起的思考 总被引:1,自引:0,他引:1
结合三峡机组励磁系统的调试及投运经验,对大型水电机组静止自励系统选型中存在的一些关键性技术课题进行分析与论证,期望得出的结论有助于在大型水轮发电机组励磁系统参数选择和在提高机组运行安全、可靠性方面提供有益的借鉴。文中提出的励磁系统设计新理念仅代表个人的观点。 相似文献
50.
References: 《计算技术与自动化》2003,22(Z1):54-57
In order to avoid unnecessary damage of electrical equipments and installations,high quality power should be delivered to the end user and strict control on frequency should be made, Therefore, it is important to estimate the power system's harmonic components with higher accuracy. This paper presents a new approach for estimating harmonic component in a power system using secant - fuzzy linear regression method. In this approach the non - sinusoidal voltage or current waveform is written as I linear function. The coefficient of this function is assumed to be fuzzy number with a membership function that has center and spread value. The time dependent quantity is written as Taylor series with two different time dependent quantities. The objective is to use the sample obtained from the transmission line to find the power system harmonic components and frequencies. We used an experimental voltage signal from a sub power station as a numerical test. 相似文献