进口灯泡贯流式机组滑环碳刷系统的改进

介绍了灯泡贯流式机组滑环碳刷系统的磨损情况，分析了滑环碳刷磨损严重的危害和滑环碳刷系统磨损的原因、就浙江省玉溪水电站滑环碳刷系统改进的方法做了详细介绍，包括：碳刷改型设计、滑环表面磨损处理、汇流排和碳刷握的改进．滑环碳刷系统改进后已运行4年，完全达到了预期的目的．     

Estimating the export and import demand for manufactured goods: The role of FDI

In this paper we estimate the demand for exports and imports of manufactured goods for a panel containing the majority of the EU countries as well as the United States and Japan. The model includes as explanatory factors both the traditional determinants of trade and also the stock of foreign direct investment (FDI). We apply panel unit root and cointegration tests allowing for heterogeneity. Whereas there is no evidence of cointegration when using just the traditional formulation, the results are favorable to the existence of long-run relationships linking the variables of the augmented model. Moreover, the results point mainly to a complementary relationship between trade and FDI.     

水管单位如何冲出困境求生存求发展

文章论述了水管单位目前产生困境的原因，并举出实例说明水管单位冲出困境的主要经验及今后把水管单位管理好，建设好的措施。     

高水头电站引水管压力波动分析与调节

高水头电站一般采用冲击式水轮发电机组,引水系统长,容易产生水压波动.文中对引水管压力波动机理进行了分析,结合电站的实际运用,介绍了调速器在改善水压波动方面所采取的调节方式.     

阿珠水电站机组机型选择

通过综合考虑技术经济指标，并针对阿珠水电站所在河流三岔河含沙量大的特点，从5种机型中优选出适合阿珠水电站具体情况的ZZA315机型作为首选机组。     

超宽带通信技术研究及最新发展动向

通过介绍一种新型的通信技术一超宽带脉冲通信技术及其信号表示形式，分析了超宽带信号的特点以及当前国内外超宽带通信最新的研究及应用情况，展望了超宽带通信的发展动向和进一步研究的课题。     

水电厂经济运行的优先表动态规划方法

基于常规动态规划方法，将负荷最优分配与开停机组合寻优过程同时在线计算，机组组合方案按参与运行的机组台数递增选取，最优负荷分配亦随机组台数递推，排除不符合日发电计划中负荷要求的机组组合，以流量最小为优先原则，存储有限项可行组合，减少中间数据存储，降低寻优维数，缩短计算时间，适合机组特性数据经常变化的要求。对12台机组的实例计算表明，合理选择有限项的个数，可较快地解算出最优开停机计划。     

Use of GTÉ-65 gas turbine power units in the thermal configuration of steam-gas systems for the refitting of operating thermal electric power plants

Thermal configurations for condensation, district heating, and discharge steam-gas systems (PGU) based on the GTé-65 gas turbine power unit are described. A comparative multivariant analysis of their thermodynamic efficiency is made. Based on some representative examples, it is shown that steam-gas systems with the GTé-65 and boiler-utilizer units can be effectively used and installed in existing main buildings during technical refitting of operating thermal electric power plants. Translated from élektricheskie stantsii, No. 6, June 2008, pp. 15–25.     

Pricing-to-Market: Price Discrimination or Product Differentiation?

We employ a vertical differentiation model to examine the potential bias in pricing-to-market results when using export unit values aggregating differentiated products. Our results show that: (i) false evidence of pricing-to-market is always found when using unit values, whether the law of one price holds or not; and (ii) the size of the bias increases with the level of product differentiation. Our simulation results support those conceptual findings. Thus, some of the positive pricing-to-market results in the literature could be an artifact of the product heterogeneity embodied in unit values rather than evidence of imperfect competition.     

Commodity Prices and Unit Root Tests

Price theory suggests that commodity prices should be stationary series. Yet, tests for unit roots rather frequently imply that these prices are not stationary. This seeming inconsistency is investigated by applying alternative specifications of unit root tests to prices of corn, soybeans, barrows and gilts, and milk. The preponderance of evidence suggests that nominal prices do not have unit roots, but the results are sensitive to the specification of the test equation. Accounting for a structural change that shifts the mean appears to be an important issue in unit root tests.