浅谈10千伏电力系统配电网络的智能化

由于我国城市供电网网架较薄弱,城市配电网也不够完善.为解决这一问题,我国已在全国200 多个城市进行城市配电网建设与改造工程,加强配电网建设,这一切为实施配电网络的智能化奠定了良好基础.许多城市在城网改造的同时,为了进一步提高供电可靠性,不断改善对电力用户的服务质量,提高配电网运行管理水平,正在开展配电智能化工程.本文主要介绍基于10 kV 电力系统配电网络的智能化在电力系统中的应用.     

Sedimentation processes and sedimentary characteristics of tidal bores along the north bank of the Qiantang Estuary

A tidal bore is a unique Earth surface process, characterized by its highly destructive energy, predictable periodicities and magni-tudes, and the production of characteristic sedimentary features. Tidal bores and associated rapid flood flows are highly turbulent flows of the upper-flow regime with a velocity over several meters per second. Reynolds (Re) and Froude (Fr) numbers, respectively, are larger than 104 and 1.0, making them significantly different from regular tidal flows but analogous to turbidity currents. Until now, understanding of tidal-bore depositional processes and products has been limited because of the difficulty and hazards involved with gauging tidal bores directly. The Qiantang bore is known as the largest breaking bore in the world. Field surveys were carried out in May 2010, along the north bank of the Qiantang Estuary to observe the occurrence of peak bores, including regular observations of current, water level and turbidity at the main channel. Several short cores were sampled on the intertidal flats to study the characteristic sedimentary features of tidal bores. Hydrodynamic and sedimentological studies show that the processes of sediment resuspension, transport and deposition are controlled primarily by the tidal bores, and the subsequent abruptly accelerated and decelerated flood flows, which only account for one tenth of each semidiurnal tidal cycle in the estuary. Tidal-bore deposits are generally poorly sorted because of rapid sedimentation after highly mixed suspension by intense turbulence. This behavior is characteristic of the absence of tractive-current depositional components in a C-M diagram. It also goes along with well-developed massive bedding, graded bedding, basal erosion structures, convolute bedding and dewatering structures. Together, these sedimentary features can constitute fingerprinting of turbidites, widely distributed in the deep-water environment. However, a tidal bore is triggered by intensely deformed tidal waves propagating into a shallow-water environment, which returns to regular tidal flows rapidly after the passage of the bore head. The tidal-bore deposits are usually bounded by the intertidal-flat deposits with typical tidal beddings at the top and on both flanks. The difference between tidal-bore deposits (TBD) and tidal sandy/muddy deposits (TSD/TMD) is evident not only in sedimentary structures, but also in the grain-size composition. They can be clearly distinguished in grain-size bivariate plots, typically the plot of mean grain size vs. standard deviation (or sorting). Some trend variations generally exist in mean grain size with TBD>TSD>TMD, sorting with TMD>TBD>TSD (larger value indicating poorer sorting), and both skewness and kurtosis with TSD>TBD>TMD. These findings will undoubtedly shed new light on our understanding of tidal-bore sedimentology, ancient tidal-bore sedimentary facies and environments, and related oil-and-gas field prospecting.     

我国光伏设备技术发展现状与趋势研究

光伏产品生产制造在当前是设备制造行业当中的新领域。目前,我国的光伏设备技术发展还处于初级发展阶段,但由于其对于产业的结构调整和产业进步有着巨大的作用,因此得到了大力的推广,并且也为设备制造业提供了极大的保障。本文主要对我国光伏设备技术的发展现状进行了分析,并对其未来发展趋势进行了进一步的讨论,希望为相关人士提供一些有益参考。     

"凝固力"FSS化学加固材料在松软煤体仰采工作面的应用

近年来,随着科学技术的迅猛发展,新型高分子材料在煤矿得到广泛应用,国内大部分生产矿井随着采深加大,巷道压力明显提高,尤其是综采工作面,在周期来压前后,出现大量片帮、冒顶,严重制约产量,并对安全生产提出严峻考验.化学加固材料在煤体合理加注后,可以有效提高煤壁硬度,有效控制片帮、冒顶事故,为均衡、正规、安全生产提供有效保障.     

多重微孔生物反应床填料选取的探讨

多重微孔颗粒生物反应床是我公司研究开发的一种经济且能强有效去除垃圾渗滤液中污染物的反应器。本文先对矿化垃圾填料和多重微孔颗粒填料的挂膜性能和粒径分布进行比较,再以上海老港垃圾填埋场调节池出水为研究对象,构建多重微孔颗粒反应床的小试模型,对比20℃条件下反应柱和多重微孔颗粒反应柱对COD、NH3-N、TN指标的去除效果。     

The impact of warrants introduction: Sign effect or magnitude effect?

The data of warrants underlying stocks was selected for the sample period from August, 2005 to December, 2009. These data the authors collected did not include the announcement date of reform of non-tradable underlying shares, and was available from Shanghai and Shenzhen stock exchanges. The event study method is employed to test the magnitude effect based on the Wild bootstrap, which is performed on the abnormal return, the cumulative abnormal return, and the standardized cumulative abnormal return. Empirical results show no evidence of magnitude effect but sign effect after warrants introduction. The authors argue that this phenomenon is caused by the migration of radical agents from stock market to warrant market.     

某砖混结构阳台挑梁加固方法及案例分析

针对某多层砖混结构阳台挑梁混凝土强度偏低,通过几种加固方案的比较采用增加钢拉杆和粘贴碳纤维布的方法进行加固处理,加固后进行荷载试验,试验表明构件满足承载力使用要求,投入使用多年,使用状况良好,表明所采用的加固方案有效,可供类似工程加固设计参考.     

程控交换机的日常维护与管理

文章通过铁通公司使用的程控交换机出现的常见故障,提出了如何维护和管理等一系列措施,以期帮助程控人员解决一些疑难问题。     

图的扩张因子

图的扩张因子是度量图的连通性的一个重要参数.得到了图的扩张因子的上界和下界,刻画了达到上界与下界的图类,给出了n-维交叉超立方体和n-维增广立方体网络的扩张因子.     

大学图书馆建筑设计中的文化要素刍议——以华中师范大学新图书馆为例

图书馆是大学最具标志性的建筑之一,它除了具有文献收藏检索、科技信息服务、学术交流研究等功能外,还应该体现一所大学的文化,体现出强烈的时代特征和人文关怀.以华中师范大学新图书馆建筑设计方案为例,探讨了当代大学图书馆建筑设计中的文化要素.