An economic investigation of the wind-hydrogen projects: A case study

Hydrogen as an energy carrier can play a significant role in reducing environmental emissions if it is produced from renewable energy resources. This research aims to assess hydrogen production from wind energy considering environmental, economic, and technical aspect for the East Azerbaijan province of Iran. The economic assessment is performed by calculation of payback period, levelized cost of hydrogen, and levelized cost of electricity. Since uncertainty in the power output of wind turbines may affect the payback period, all calculations are performed for four different turbine degradation rates. While it is common in the literature to choose the wind turbine based on a single criterion, this study implements Multi-Criteria Decision-Making (MCDM) techniques for this purpose. The results of Step-wise Weight Assessment Ratio Analysis illustrates that economic issue is the most important criterion for this research. The results of Weighted Aggregated Sum Product Assessment shows that Vestas V52 is the most suitable wind turbine for Ahar and Sarab cities, while Eovent EVA120 H-Darrieus is a better choice for other stations. The most suitable location for wind power generation is found to be Ahar, where it is estimated to annually generate 2914.8 kWh of electricity at the price of 0.045 $/kWh, and 47.2 tons of hydrogen at the price of 1.38 $/kg, which result in 583 tons of CO₂ emission reduction.     

Protection of power transformer using multi criteria decision-making

Power transformers are protected by different relays that operate independently. Malfunction of each relay has a major role in reducing the reliability of the protection system. In order to mitigate the main drawbacks of the power transformer relays, an overall protection scheme is presented in this paper. This scheme proposes a novel multi criterion algorithm using decision-making based on fuzzy logic. In this paper the outputs of restricted earth fault relay and a directional check unit, are combined with the output of the differential protection relay. Therefore, problems that are pertaining to independent operation of each relay have been mitigated and the relays cover protection blind spots of each other. The improved power transformer protection (IPTP) scheme enhances the sensitivity and reliability of the power transformer protection. Extensive simulations are used to measure the effectiveness and merit of the proposed IPTP relay. The above efforts result in a multi criteria approach for protection of power transformers.     

用于磁场测量的高精度500A/30V零压开关直流稳流电源

研制了一种带有无源辅助网络的全桥移相脉宽调制零压开关(FB PSPWMZVS)高精度磁铁稳流电源,并在电磁铁磁场测量中得到应用,其电流稳定度在8h内优于±1×10-4。     

现代住区规划的几点思考

通过对居住区规划中住区交通组织、环境建设,以及住宅配套现实处理方法的分析,指出现代住区的规划要根据当地实际情况,因地制宜组织住区交通网络,合理整合住宅内外环境,适度超前建设配套设施。     

Project to develop school education services in Delhi, India

There are many ways in which quantitative decision models can be applied in project management. The introduction of a project evaluation review technique network model to the development of a school education service in the city of Delhi, India, is described. The reasons for choosing this method, its advantages and limitations are discussed. Examples of the information obtained from the model are presented and explained.     

二滩水电站油、水、风系统设备运行与改造

水电站辅助设备的运行直接影响水电站运行的安全性和可靠性。二滩水电站投运初期，油、水、风系统先后出现了许多问题，通过应用新产品和新技术对其进行了改造。为水电厂辅助设备的设计、选型、安装提供了宝贵的经验，并对水电厂辅助设备的检修、调试和运行维护有一定的指导作用。     

辅助消声器在轿车排气消声器性能研究中的应用

引入辅助消声器（BAM）原理，对T15汽车加速行驶产生的“噗噗”声进行试验分析，发现了原消声器系统存在的问题，并对原消声器结构做了优化，解决了“噗噗”声问题。     

相控阵AEW雷达杂波抑制的辅助通道方法研究

本文分析了相控阵机载预警(AEW)雷达杂波抑制的现有两种辅助通道降维技术(Klemm方法和简化方法)的性能，并提出了一种新的辅助通道方法。新方法的基本思想为：根据待处理距离段内各距离单元杂波能量在波束一多普勒域分布的统计特征自适应地选取辅助通道，使所选辅助通道实时地逼近杂波子空间，从而有效抑制杂波。本文方法不但可以用于非正侧视阵情况，而且误差鲁棒性好。计算机仿真结果证实了其有效性。     

动态多目标决策问题的灰色分析方法

将用于固定时间截面下静态多目标决策的灰色关联理论推广到动态情形，引入局部理想最优效果和整体理想最优效果的概念，提出一种新型的动态多目标决策问题的灰色关联模型，并通过算例说明该方法的合理可行性。