The planning and comprehensive utilization of Three Gorges Project

Abstract: As the most significant water project, the Three Gorges Project (TGP) was designed to take care of multiple objectives for water utilization such as flood control, power generation and navigation. The implementation of the project will improve the flood safety level of Jingjiang reach to more than 100-year return period, which will reduce greatly the flood risk at the mid-lower reaches of Changjiang River, produce huge quantity of energy for the central, east and south China, and improve significantly the navigation conditions of Chuanjiang River. Meanwhile, the operation of the TGP in dry season which will compensate the downstream water resources, will as well deepen the navigation channel and thus improve the navigation conditions in the middle river reach. With the increasing demands raised from various aspects of the society, new requirements will be made for the TGP for the purpose of harnessing, development and protection of the Yangtze River Basin. Therefore, it will be a long-term task for the operation of TGP on how to optimize the water resources utilization and implement an effective operation.     

Scientific and technological progress and innovation of Three Gorges Project

In the design,construction and operation periods of the Three Gorges Project (TGP),great challenges have been met in different fields such as water resources and hydropower project construction,electromechanical equipment manufacture and ecological environment protection.In view of the key techniques and difficulties in the construction period,scientific and technological breakthroughs have been made by the experts and scholars of various fields and a series of innovative achievements are gained,which make the scientific and technological levels in relevant fields improved.Some major innovative achievements in the construction and operation of TGP are enumerated,which are significant for the hydropower project construction and clean energy development in the future in China.     

The construction design and practice of Three Gorges Project

The construction of Three Gorges Project (TGP) is characterized by large construction scale,high construction intensity and complexity in technology.In view of various technical difficulties such as navigation in construction period,two river closures,high-intensity concrete and earth-rock construction,high-intensity construction and demolition of RCC (roller compacted concrete) cofferdam in stage III and immediate navigation of double-line five-step shiplock after impoundment of reservoir,the scheme of river diversion during construction is adopted,namely "diversion in 3 stages,open channel navigation and cofferdam power generation".The practice and innovation achievements in river diversion during construction as well as earth-rock and concrete construction are presented emphatically.     

三峡工程论证决策过程及其实践检验

举世瞩目的三峡水利枢纽工程是世界上规模最大的水电站,也是中国有史以来建设的最大型水利水电工程。2010年10月26日,三峡水库蓄水首次达到设计水位175 m,这标志着其防洪、发电、航运等各项功能达到设计要求。三峡工程从构想、论证、设计、建设至竣工全面投入运行历时近百年。当初兴建三峡工程的构想是如何提出的？三峡工程究竟起什么作用？存在什么分歧意见？是如何进行论证的？论证的结论怎样？这是许多人关心而又不太了解的,笔者在文中做了扼要的介绍,以纪念世纪之梦的实现。     

基于“工程背景”的制图类课程教学改革和探索

制图类课程是工科大学生必修的主要技术基础课程。通过对课程内容的重组,营造＂工程背景＂氛围,借鉴＂项目教学法＂、＂分层次教学法＂等各种先进教学模式和手段,充分调动工科大学生学习积极性与主动性。利用多元评价理论,进行考核模式的改革,全面客观地评价学生,教学效果明显改善,走向良性循环的轨道。     

“项目化、层次化”的计算机专业课外实践教学体系构建与实践

针对民族地区IT产业相对薄弱,尤其地处非中心城市的高校难以为计算机专业学生提供集中实践的情况,本文提出并构建了一种"项目化、层次化"的计算机专业课外实践教学体系,利用学校现有的自身资源并进行课外实践锻炼,实践表明这种体系对于提高学生动手能力具有较好的促进作用。     

基于数据挖掘技术的学生成绩预警应用研究

学习成绩是评价一个学生学习情况的最重要最基础的指标,对学习成绩的分析有利于老师掌握学生的学习情况,进行针对性地进行教学辅导,而对学生而言,能提前知道自己未来课程在学习过程中出现的情况也有利于学生发现自身存在的问题并提前加以防范.现有的研究工作大多是基于对课程、历史成绩或行为数据的分析来对学生的总成绩进行预测,很少有研究将学生行为与学生课程成绩等方面结合起来综合全面的预测学生未来所有的课程的学习情况,对此,本文从一个新的角度出发,利用学生的行为、个人属性和历史成绩等三个方面数据,根据学生未来不同课程动态的进行影响因素的选择,并利用支持向量机对学生成绩进行预警,为数据挖掘技术在教育领域的应用做了一些探索性工作.     

DSSC用钒掺杂二氧化钛薄膜的制备及性能表征

为获得高性能电池用二氧化钛薄膜,采用射频磁控溅射法制备了掺V的TiO2薄膜.使用分光光度计、催化反应器和电化学工作站等研究了溅射时间、退火温度和掺钒量等对TiO2薄膜光学性能、光催化性能和超亲水性和电学性能的影响.研究表明溅射时间越长,薄膜紫外光区的透射率越低.3h条件下,在小于400nm区域内,溅射薄膜的透射率已经降至60%以下.退火温度对薄膜的亲水性能和光催化性能有一定的影响,经400℃退火的薄膜具有较好的光催化性能和超亲水性.掺V使薄膜的吸收峰红移和禁带宽度变窄,当掺杂量为0.5%时,TiO2薄膜红移量最大,禁带宽度变也为2.88eV.将制备的掺钒二氧化钛薄膜制备成染料敏化太阳能电池(DSSC),结果表明掺V量为0.5%的二氧化钛薄膜的光响应范围增大,所制备电池的开路电压和短路电流都高于未掺杂电池,其中短路电流从24.82μA增大到了88.15μA.表明电池的综合性能有所提高.     

Fe3O4@NiSiO3纳米催化剂制备及催化臭氧化降解对苯二甲酸性能研究

采用水热法和溶胶凝胶法制备Fe₃O₄@SiO₂纳米颗粒,经表面镍刻蚀得到Fe₃O₄@NiSiO₃磁性纳米催化剂。利用XRD、TEM和VSM等手段表征催化剂的晶体和表面结构。构建类均相催化臭氧化体系,考察其催化降解对苯二甲酸性能。结果表明：在臭氧通入量10.52 mg.min_-1、催化剂投加量40 mg.L_-1和初始溶液pH=9的条件下,催化臭氧化反应20 min时对苯二甲酸降解率为78.13%,TOC去除率27.25%;5次循环实验后,PTA降解率仅下降2.75%。     

地方政府绩效预算分析

随着市场经济的日趋成熟,公众对政府合理高效地配置公共资源的预期也日益增强。分析了绩效预算的应用背景,阐述了绩效预算在西方的发展历程、中国地方政府预算体制改革的尝试及存在的问题,并对相关问题进行了思考。