机载用电设备的供电适应性试验系列标准制定与实施

机载用电设备的供电适应性试验是对各类机载用电设备在各种供电状态下的性能以及用电设备工作对供电系统影响的验证，是保证用电设备（尤其是大功率电子设备）与飞机供电系统相兼容的重要措施和方法。本文阐明了我国机载用电设备的供电适应性试验系列标准的组成和相互关系，着重对供电适应性试验方法标准的定位、框架、结构要素的确定和主要内容进行了分析，并提出实施供电适应性方法标准的建议。     

Measurements of heat transfer and pressure in a trailing edge cavity of a turbine blade

 An experimental investigation is conducted to obtain the heat transfer and pressure drop data for an integral trailing edge cavity test section that simulates a novel turbine blade's internal cooling passage with bleed holes. Local heat transfer is measured on both the suction and pressure sides by a transient liquid crystal technique, while pressures at six positions are recorded by pressure calibrators. Moreover, flow characteristic and its effect on heat transfer are analyzed for conditions with or without bleed flow. The experimental results show that, in the cases with bleed flow, local heat transfer on the pressure side exceeds that on the suction side in the first and second channels. In the cases without bleed flow, in the first and third channels, local heat transfer on the suction side weakens whilst it increases significantly on the pressure side. For the second channel, non-bleed condition leads to a more balanced heat transfer distribution between the upstream and downstream channel. Besides, after the bleed holes are blocked, heat transfer in the first bend region on the suction side declines sharply, while the opposite phenomenon occurs for the second bend region on the pressure side. In both bleed and non-bleed cases, the total pressure of six measurement positions decreases continuously along the channel at the same Reynolds number and it promotes for higher Reynolds number. Among all the measurement points, under the same flow rate condition, the highest speed occurs at Position 5, which also shows the maximum difference between the total and static pressures. When the bleed holes are blocked, the total pressure at each measurement position appears to increase.     

Student and Teacher Attitudes towards the Role of the Mother Tongue in English Class: Report of a Questionnaire Study

This article presents the results of a questionnaire study on the role of the mother tongue in English class. The participants were 50 students and 10 teachers. The goal of the study was to investigate (1) the attitudes of both teachers and students towards the use of Chinese; (2) the actual and potential function of Chinese in English class. The results of this study indicate that Chinese was still quite extensively used in English class,that both the teachers and the students respond positively to a reaso...     

Multi-objective Optimization Method for Automatic Drilling and Riveting Sequence Planning

 There are numerous riveting points on the large-sized aircraft panel, irregular row of riveting points on delta wing. It is es-sential to plan the riveting sequence reasonably to improve the efficiency and accuracy of automatic drilling and riveting. Therefore, this article presents a new multi-objective optimization method based on ant colony optimization (ACO). Multi-objective optimization model of automatic drilling and riveting sequence planning is built by expressing the efficiency and accuracy of riveting as functions of the points’ coordinates. In order to search the sequences efficiently and improve the quality of the sequences, a new local pheromone updating rule is applied when the ants search sequences. Pareto dominance is incorporated into the proposed ACO to find out the non-dominated sequences. This method is tested on a hyperbolicity panel model of ARJ21 and the result shows its feasibility and superiority compared with particle swarm optimization (PSO) and ge-netic algorithm (GA).     

关于企业标准化工作的几点认识

阐述标准化在企业科学管理、参与市场竞争方面的作用,提出企业应建立企业标准体系以保护企业拥有的自主知识产权以及加快实施标准化战略和国际化的必要性。     

APSCO: Opportunities and Challenges Together

The Asia-Pacific Space Cooperation Organization (APSCO) is an inter-governmental organization.In November 1992, China, Pakistan and Thailand jointly proposed the institution-alization of the mechanism Multilateral Cooperation in Space Technology and Applications (AP-MCSTA). After 16     

储氢合金的性质及发展趋势

本文介绍了储氢合金的性质，Ｎｉ－ＭＨ电池原理，以及储氢合金对Ｎｉ－ＭＨ电池所产生的影响，根据目前科学技术的发展以及市场的需求，提出了未来储氢合金及Ｎｉ－ＭＨ电池的发展趋势。     

数据采集系统直流增益和线性度的精确评价

介绍了两种新的精确评价数据采集系统的直流增益和线性度的方法与过程,即“按码精确评价法”和“定间距（为量化误差整数倍）精确评价法”。同时讨论了介绍了的优缺点及应用。     

重量的一种遥测式监测系统

本文提出一种重量信号的无线传输和测量方法。重量信号经传感顺转换成电信号，再经Ｖ／Ｆ变换后调频发射，接收信号解调后单片机处理。单片机的信号处理采用电子计数器测频方法，经过计算送显示单元，实现重量信号的遥测。     

Characteristics of low-latitude whistlers and their relation with f0F2 and magnetic activity

Some results obtained from the characteristics of low-latitude whistlers received at Wuchang (Geomag. Lat. 19.2°N), Zhanjiang (9.8°N) and Yulin (6.4°N) are presented. The observations cover three years at Wuchang, two years at Zhanjiang, one year at Yulin.