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On the geo-basis of river regulation in the lower reaches of the Yellow River

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Science China Earth Sciences 2012年第10期55卷 530-544页

作者： liu guowei Nanjing Hydraulic Research Institute Nanjing 210029China

This paper investigates the important scientific problem of river regulation strategies in the lower reaches of the Yellow River, and discusses the "geo-basis" of river regulation. The concept of a geo-basis to river regulation in the lower Yellow River was discussed in terms of subsidence and sedimentation features of the fiver plain; channel features, erosion characteristics of the Loess Plateau and storm-flood features of the middle and lower reaches. The geographic features of the lower Yellow River have gradually changed since the Holocene but there has been no fundamental change. Based on an analysis of the geo-attributes of the lower reaches of the Yellow River, several conclusions on its river regulation were made. The release of sediment should be the first measure of river regulation because of deposition in the lower reaches. The fiver channels should be provided with adequate space for wandering in the lower reaches. The tail river should be also provided with necessary wandering space because of weak marine dynamics in the estuary area and changes in the delta. Because the erosion environ- ment of the Loess Plateau will not fundamentally change, river harnessing of the middle reaches should focus on improving the plateau morphology, which can be done by reducing the fragmentation of terrain and building a planation surface. Eco- remediation should focus on converting farmland to grassland. There may be extreme floods in the future, as has occurred pre- viously, thus an extreme flood defense system should be considered for the lower reaches. A periodic law for regulation in the Yellow River is discussed. We also discuss how the current use of the lower reaches of the Yellow River is unsustainable and it is urgent to research artificial rechanneling and the creation of new flow paths for the lower reaches.

关键词： river geo-attributes river regulation the Yellow River floods

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On geo-basis of river regulation——A case study for the middle reaches of the Yangtze River

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Science China(Technological Sciences) 2008年第5期51卷 494-505页

作者： liu guowei Nanjing Hydraulic Research Institute, Nanjing 210029, China Nanjing Hydraulic Research Institute Nanjing China

From the point of view that people have to obey the river's geo-attributes in the river regulation, the definition and the meaning of the geo-attributes of a river are discussed. The geo-basis of the river regulation of the middle reaches of the Yangtze River is expounded in five aspects, including the structural geomorphology environment of flood storage and discharge, the distribution characteristics of subsidence and the sedimentation areas of Dongting Basin, the history evolution of Jianghan Basin, the function of Jianghan Basin and Dongting Basin as the flood water detention areas of Jingjiang River reach in ancient time, and the geological characteristic of Jingjiang River reach. Based on the geo-attributes of the middle reaches of the Yangtze River, some ideas about the middle reach regulation of the Yangtze River are put forward: to process the interchange between the lakes and diked marsh areas in Dongting Basin, to canal the new river route as the flood diversion channel of Jingjiang River reach with the paleo river, to recover the function of Jianghan Basin as flood detention area of the middle reaches. And we should take into consideration the geo-environment of the whole Yangtze River in the river regulation of middle reaches.

关键词： river geo-attributes river regulation the Yangtze River flood

Adaptive Reference Power Based Voltage Droop Control for VSC-MTDC Systems

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Journal of Modern Power Systems and Clean Energy 2023年第1期11卷 381-388页

作者： Yizhen Wang Fengliang Qiu guowei liu Ming Lei Chao Yang Chengshan Wang Key Laboratory of Smart Grid of Ministry of Education Key Laboratory of Smart Energy&Information Technology of Tianjin MunicipalityTianjin 300072China Shenzhen Power Supply Bureau Co. Ltd.Shenzhen 518001China Sichuan Energy Internet Research Institution Tsinghua UniversityChengdu 610213China IEEE

Featuring low communication requirements and high reliability,the voltage droop control method is widely adopted in the voltage source converter based multi-terminal direct current(VSC-MTDC)system for autonomous DC voltage regulation and ***,the traditional voltage droop control method with fixed droop gain is criticized for over-limit DC voltage deviation in case of large power disturbances,which can threaten stable operation of the entire VSCMTDC *** tackle this problem,this paper proposes an adaptive reference power based voltage droop control method,which changes the reference power to compensate the power deviation for droop-controlled voltage source converters(VSCs).Besides retaining the merits of the traditional voltage droop control method,both DC voltage deviation reduction and power distribution improvement can be achieved by utilizing local information and a specific control factor in the proposed *** principles and key features of the proposed method are *** analyses on the effects of the control factor on DC voltage deviation and imbalanced power-sharing are discussed,and the selection principle of the control factor is ***,the effectiveness of the proposed method is validated by the simulations on a five-terminal VSC based high-voltage direct current(VSC-HVDC)system.

关键词： DC voltage deviation power-sharing reference power voltage droop control voltage source converter(VSC) multi-terminal direct current(MTDC)

Kongsheng Zhenzhong pill's effect on the learning and memory ability and its neuroprotective effects in vascular dementia rats

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Neural Regeneration Research 2011年第30期6卷 2342-2346页

作者： Xuming Ji Huayun Yu Bin Ouyang guowei liu Zhichun Wu Heng liu Fang Du College of Basic Medical Science Shandong University of Traditional Chinese Medicine Jinan 250355 Shandong Province China Otolaryngology Laboratory Qilu Hospital of Shandong University Jinan 250012 Shandong Province China Research Imaging Institute University of Texas Health Science Center at San Antonio Texas USA

Clinical reports have demonstrated that the Kongsheng Zhenzhong pill （KSZZP）, a classical prescription deriving from Valuable Prescription for Emergencies, has good therapeutic effects on vascular dementia. However, the mechanisms that mediate its effects remain unclear. In this study, the expression of N-methyI-D-aspartate receptor 1 mRNA, the content of nitric oxide, and the concentration of calcium in neurons was determined with in situ hybridization, spectrophotometry and flow cytometry, respectively. In addition, the expressions of N-methyI-D-aspartate receptor 1, nerve growth factor protein, and glial cell line-derived neurotrophic factor protein were detected with immunohistochemistry. We found that KSZZP could significantly decrease the expression of N-methyI-D-aspartate receptor 1 mRNA and protein, the content of nitric oxide, and the concentration of calcium in neurons. KSZZP also increased the expression of nerve growth factor and glial cell line-derived neurotrophic factor protein in the hippocampus CA1 region and in the cerebral cortex. Morris water maze and passive avoidance tests verified that KSZZP ameliorated the cognitive impairments of vascular dementia rats. Moreover, the KSZZP-induced improvements in the cognitive functions of vascular dementia rats were correlated with both inhibition of N-methyl-D-aspartate-induced excitable neurotoxicity and elevation of neurotrophic factor expression.

关键词： Kongsheng Zhenzhong pill vascular dementia learning and memory ability neuroprotective effects

The LA-ICP-MS zircons U-Pb ages and geochemistry of the Baihua basic igneous complexes in Tianshui area of West Qinling

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Science China Earth Sciences 2007年第Z2期50卷 264-276页

作者： PEI XianZhi DING SaPing ZHANG guowei liu HuiBin LI ZuoChen LI GaoYang liu ZhanQing MENG Yong Key Laboratory of Western China's Mineral Resources and Geological Engineering Ministry of Education Faculty of Earth Science and Land Resources Chang'an University Xi'an 710054 China Key Laboratory of Western China's Mineral Resources and Geological Engineering Ministry of Education Faculty of Earth Science and Land Resources Chang'an University Xi'an 710054 China State Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi'an 710069 China Key Laboratory of Western China's Mineral Resources and Geological Engineering Ministry of Education Faculty of Earth Science and Land Resources Chang'an University Xi'an 710054 China

Baihua meta-igneous complex consists mainly of pyroxenite-gabbro(diorite)-diorite-quartz diorite. They form a complete comagmatic evolutionary series. The geochemical characteristics of basic-interme- diate basic igneous rocks indicate that they belong to a tholeiite suite. The REE distribution pattern is nearly flat type and LREE is slightly enriched type, and their primitive mantle-normalized and MORB-normalized trace element spider diagrams are generally similar; the LIL elements (LILE) Cs, Ba, Sr, Th and U are enriched, but Rb, K and the HFSEs Nb, P, Zr, Sm, Ti and Y are relatively depleted. All these show comagmatic evolution and origin characteristics. The tectonics environment discrimination of trace element reveals that these igneous complexes formed in an island-arc setting. The LA-ICP-MS single-zircons U-Pb age of Baihua basic igneous complex is 434.6±1.5 Ma (MSWD = 1.3), which proves that the formation time of the island-arc type magmatite in the northern zone of West Qinling is Late Ordovician or Early Silurian, also reveals that the timing of subduction of paleo-ocean basin represented by the Guanzizhen ophiolite and resulting island-arc-type magmatic activities is probably Middle-Late Ordovician to Early Silurian.

关键词： basic igneous complex, island-arc setting, LA-ICP-MS, zircons U-Pb isotopic ages, Tianshui area, West Qinling

流线型结构特征造型方法及其在高速列车设计中的应用

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计算机辅助设计与图形学学报 2005年第6期17卷 1196-1201页

作者：刘国伟中南大学轨道交通安全实验室长沙410075

提出了一种基于自由曲面的流线型结构特征造型方法,并将其应用于200kmh电动车组“先锋号”的流线型结构设计之中.流线型结构特征所描述的实体模型对自由曲面外形的变化具有自适应性,该方法便于流线型结构数据存取和修改,可在自由曲面外... 详细信息

提出了一种基于自由曲面的流线型结构特征造型方法,并将其应用于200kmh电动车组“先锋号”的流线型结构设计之中.流线型结构特征所描述的实体模型对自由曲面外形的变化具有自适应性,该方法便于流线型结构数据存取和修改,可在自由曲面外形和流线型结构各种参数多次修改的情况下自动生成流线型结构实体;大幅度地减少了人机交互时间,解决了高速列车流线型结构实体造型过程中设计周期过长的问题.

关键词：自由曲面特征造型结构流线型高速列车

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流曲线概念及造型方法

计算机辅助设计与图形学学报 2006年第12期18卷 1891-1896页

作者：刘国伟中南大学轨道交通安全教育部重点实验室长沙410075

定义了一种可用于造型、具有明确流体力学意义的功能曲线——流曲线·将直匀流绕物面作二维无旋不可压缩定常流动时的流函数表达为曲面后,利用流函数曲面控制边界与流曲线的对应关系,采用拉普拉斯方程第一边值逆问题的数值解法,提出了... 详细信息

定义了一种可用于造型、具有明确流体力学意义的功能曲线——流曲线·将直匀流绕物面作二维无旋不可压缩定常流动时的流函数表达为曲面后,利用流函数曲面控制边界与流曲线的对应关系,采用拉普拉斯方程第一边值逆问题的数值解法,提出了来流为直匀流的流曲线造型方法并给出了实例·结果表明:流曲线定义及造型方法可用于与流体有关的平面曲线造型,可反映流场信息并对曲线的流体力学性能进行初步评估·

关键词：流线流曲线功能曲线造型流函数拉普拉斯方程

Comparison and analysis of the source culture and the target culture of the TCM intercultural communication

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World Journal of Integrated Traditional and Western Medicine 2016年第1期2卷 12-16页

作者： liu guowei Foreign Languages College Shandong University of Traditional Chinese MedicineJi＇ nan 250355China

In the process of TCM intercultural communication, as a source culture, TCM embodies the essences of excellent traditional Chinese culture by absorbing the essence of Confucianism, Daoism and Buddhism and gradually evolving into a profound philosophical and cultural system during its long development, meanwhile, it has accumulated tremendous medical achievements and has been abundant in famous doctors in almost all dynasties. In short, TCM is profound both in medical practice and philosophy and culture, which endows TCM the characteristics of cultural essence and medical uniqueness, in addition to its scientific nature which has been proved historically, all of the above-mentioned factors form the basis and guarantee of the TCM intercultural communication, in which TCM is a source culture. In contrast, the western culture shows significant difference as a target culture, from which the western medicine is developed. The major differences manifest in： western culture distinguishes mankind from heaven while traditional Chinese culture believes in the harmony between man and nature; the difference between micro rational thinking and overall perceptual thinking; the difference between individual standard and organic whole. Despite the great difference, western society welcomes TCM due to its unique effect, therefore, it is of vital significance to compare and analysis the two ends of the TCM intercultural communication, namely the source culture and the target culture, to find effective means to promote the TCM intercultural communication. The current tendency of the integration of TCM and western medicine has proved the possibility and feasibility of TCM intercultural communication.

关键词： TCM Intercultural communication Sourceculture Target culture

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水文科学的基本问题及当代前沿

水科学进展 2020年第5期31卷 685-689页

作者：刘国纬南京水利科学研究院江苏南京210029

回顾了新中国70年来水文科学的发展历程。阐述了水文科学的基本问题及其当代前沿:水圈及其与地球其他圈层的界面过程;水文循环及人类活动对水文循环的扰动;水文学研究的特点及其方法论;水文知识的应用等。提出了划分水文科学分支学科的... 详细信息

回顾了新中国70年来水文科学的发展历程。阐述了水文科学的基本问题及其当代前沿:水圈及其与地球其他圈层的界面过程;水文循环及人类活动对水文循环的扰动;水文学研究的特点及其方法论;水文知识的应用等。提出了划分水文科学分支学科的科学基础,建议将水文科学划分为普通水文学、水文气象学、陆地水文学、生态水文学和应用水文学5个分支学科。

关键词：水文科学水圈水文循环地球圈层人类活动影响水文学方法论