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微挑消力池的数值模拟与试验研究

四川大学学报（工程科学版） 2011年第S1期43卷 12-17页

作者：程飞刘善均四川大学水力学及山区河流开发保护国家重点实验室四川成都610065

针对微挑消力池,通过水工模型试验和3维RNGk-ε紊流模型数值模拟研究了此体型消力池的水力特性,计算结果显示其水流特性、水面线特征、流速及压力分布与模型试验结果吻合,同时揭示了微挑消力池不同于常规反弧平底消力池的特性。模拟计... 详细信息

针对微挑消力池,通过水工模型试验和3维RNGk-ε紊流模型数值模拟研究了此体型消力池的水力特性,计算结果显示其水流特性、水面线特征、流速及压力分布与模型试验结果吻合,同时揭示了微挑消力池不同于常规反弧平底消力池的特性。模拟计算与模型试验结果均表明,与常规反弧平底消力池相比,微挑消力池可以造成自入池段水流较强的紊动,降低临底流速,减小消力池底板冲磨破坏的可能。

关键词：微挑消力池水力特性数值模拟紊动消能

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川中丘陵区蓄水池设计研究

水电能源科学 2010年第3期28卷 81-83页

作者：魏琳雷孝章张广兴四川大学水利水电学院四川成都610065 四川大学水力学与山区河流开发保护国家重点实验室四川成都610065

针对川中丘陵区水土流失严重、兴建骨干水利工程难度大带来的生态环境问题,依据地形选择径流汇集处为集水区,基于用水量和来水量提出了修建不同容量的蓄水池,并介绍了蓄水池的选址原则、设计方案、配套设施及管理运用措施。实践证明,因... 详细信息

针对川中丘陵区水土流失严重、兴建骨干水利工程难度大带来的生态环境问题,依据地形选择径流汇集处为集水区,基于用水量和来水量提出了修建不同容量的蓄水池,并介绍了蓄水池的选址原则、设计方案、配套设施及管理运用措施。实践证明,因地制宜修建蓄水池是控制水土流失、改善生态环境的有效措施,可供借鉴。

关键词：川中丘陵水土流失蓄水池附属设施管理运用

SCALE EFFECT OF I MPINGING PRESSURE CAUSED BY SUBMERGED JET

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Journal of Hydrodynamics 2005年第4期17卷 478-482页

作者： TIAN Zhong XU Wei-lin WANG Wei LIU Shan-jun DONG Jian-wei state key {2. laboratory of High Speed Flows Sichuan University Chengdu 610065 China Military Oil Supply engineering Department Logistical Engineering University Chongqing 400016China

The characteristics of the impinging pressure at the jet equipment where the maximum jet velocity can reach 50m/s were studied. By comparing the impinging pressure with the one measured at the low velocity conditions, two conclusions of the scale effect are drawn： firstly, the velocity attenuation degree is smaller than that of low velocity jet, and secondly, the relative impinging width is narrower than that of low-velocity jet. The reasons of the scale effect of the impinging pressure were elucidated through numerical simulation.

关键词： scale effect impinging pressure high-velocity jet numerical simulation

Impacts of permafrost changes on alpine ecosystem in Qinghai-Tibet Plateau

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Science china Earth Sciences 2006年第11期49卷 1156-1169页

作者： WANG Genxu1,3 , LI Yuanshou2., WU Qingbai2.& WANG Yibo3 1. Institute of mountain Hazards and Environment, Chinese Academy of Sciences, chengdu 610041,{2. 2. Cold and Arid Regions Environmental and engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000,{2. 3. Resource and Environment School, Lanzhou university, Lanzhou 730000,{2. 1. Institute of mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China 3. Resource and Environment School Lanzhou University Lanzhou 730000 China 2. Cold and Arid Regions Environmental and engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Alpine cold ecosystem with permafrost environment is quite sensitive to climatic changes and the changes in permafrost can significantly affect the alpine ecosystem. The vegetation coverage, grassland biomass and soil nutrient and texture are selected to indicate the regime of alpine cold ecosystems in the Qinghai-Tibet Plateau. The interactions between alpine ecosystem and permafrost were investigated with the depth of active layer, permafrost thickness and mean annual ground temperature (MAGTs). Based on the statistics model of GPTR for MAGTs and annual air temperatures, an analysis method was developed to analyze the impacts of permafrost changes on the alpine ecosystems. Under the climate change and human engineering activities, the permafrost change and its impacts on alpine ecosystems in the permafrost region between the Kunlun mountains and the Tanggula Range of Qinghai-Tibet Plateau are studied in this paper. The results showed that the per- mafrost changes have a different influence on different alpine ecosystems. With the increase in the thickness of active layer, the vegetation cover and biomass of the alpine cold meadow exhibit a significant conic reduction, the soil organic matter content of the alpine cold meadow ecosystem shows an exponential decrease, and the surface soil materials become coarse and gravelly. The alpine cold steppe ecosystem, however, seems to have a relatively weak relation to the permafrost environment. Those relationships resulted in the fact that the distribution area of alpine cold meadow decreased by 7.98% and alpine cold swamp decreased by 2..11% under the permafrost environment degradation during recent 15 years. In the future 50 years the alpine cold meadow ecosystems in different geomorphologic units may have different responses to the changes of the permafrost under different climate warming conditions, among them the alpine cold meadow and swamp ecosystem located in the low mountain and plateau area will have a relatively

关键词： permafrost environment, alpine cold ecosystem, statistics relationship, climate change, impacts, Qinghai-Tibet Plateau.

Information Detection of Seismic Debris Flow by UAV High-resolution Image Based on Transfer Learning

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Earthquake Research in china 2019年第1期33卷 112-119页

作者： GUO Jiawei LI Yongshu WANG Hongshu LU Heng WANG Xiaobo Faculty of Geosciences and Environmental engineering Southwest Jiaotong University Information Technology Center of chengdu Planning and Management Bureau Department of Surveying and Mapping engineering Sichuan Water Conservancy Vocational College state key {2. of hydraulics and mountain river engineering Sichuan University College of Hydraulic and Hydroelectric engineering Sichuan University Provincial Geomatics Center of Qinghai Geomatics Technology and Application key laboratory of Qinghai Province

A large number of debris flow disasters(called Seismic debris flows) would occur after an earthquake, which can cause a great amount of damage. UAV low-altitude remote sensing technology has become a means of quickly obtaining disaster information as it has the advantage of convenience and timeliness, but the spectral information of the image is so scarce, making it difficult to accurately detect the information of earthquake debris flow disasters. Based on the above problems, a seismic debris flow detection method based on transfer learning(TL) mechanism is proposed. On the basis of the constructed seismic debris flow disaster database, the features acquired from the training of the convolutional neural network(CNN) are transferred to the disaster information detection of the seismic debris flow. The automatic detection of earthquake debris flow disaster information is then completed, and the results of object-oriented seismic debris flow disaster information detection are compared and analyzed with the detection results supported by transfer learning.

关键词： Earthquake Debris flow UAV high-resolution image Transfer learning Information detection

Impact of land-use change on hydrological processes in the Maying river basin, china

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Science china Earth Sciences 2006年第10期49卷 1098-1110页

作者： WANG Genxu1,3, ZHANG Yu2. LIU Guimin2.& CHEN Lin3 1. Institute of mountain Hazards and Environment, Chinese Academy of Sciences, chengdu 610041,{2. 2. Cold and Arid Regions Environmental and engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000,{2. 3. Resource and Environment School, Lanzhou university, Lanzhou 730000,{2. 1. Institute of mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China 3. Resource and Environment School Lanzhou University Lanzhou 730000 China 2. Cold and Arid Regions Environmental and engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Since the 1960s, dramatic changes have taken place in land-use patterns characterized by the persistent expansion of cultivated land and a continuous decrease in natural woodland and grassland in the arid inland river basins of china. It is very important to assess the effects of such land-use changes on the hydrological processes so vital for water resource management and sustainable development on the catchment scale. The Maying river catchment, a typical arid inland watershed located in the middle of the Hexi Corridor in northwest china, was the site chosen to investigate the hydrological responses to land-use changes. The annual runoff, base flow, maximum peak flow, and typical seasonal runoff in both spring and autumn flood periods were selected as the variables in the hydrological processes. Statistical-trend analysis and curvilinear regression were utilized to detect the trends in hydrological variables while eliminating the climatic influence. The relationship between cultivated land-use and hydrological variables was analyzed based on four periods of land-use variation data collected since 1965. A runoff model was established composed of two factors, i.e., cultivated land use and precipitation. The impact of land use changes, especially in the large ar- eas of upstream woodland and grassland turned into cultivated lands since 1967, has resulted in a mean annual runoff decrease of 2..12., a base flow decline of 35.32., a drop in the maximum peak discharge of 35.77%, and mean discharge decreases in spring and autumn of 36.05% and 2..87% respectively, of which the contribution of cultivated land expansion to the influence of annual runoff amounts to 77%-80%, with the contribution to the influence of spring discharge being 73%-81%, and that to the influence of base flow reaching 62.-65%. Thus, a rational regulation policy of land use patterns is vitally important to the sustainable use of water resources and the proper development of the entire catchment.

关键词： land-use change, arid inland river catchment, hydrological process, impact, Maying river.

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斜坡上非均匀沙起动条件初探

水力发电学报 2004年第4期23卷 78-81,87页

作者：何文社曹叔尤袁杰戴会超兰州交通大学土木工程学院中国长江三峡工程开发总公司宜昌443002 中国长江三峡工程开发总公司

在经典力学的基础上 ,以某一概率作为定量起动标准。考虑到床面颗粒的相互隐暴影响 ,引入了等效粒径来研究泥沙的起动条件。推导了斜面上非均匀沙的起动条件。计算得到了泥沙起动时临界无量纲切应力参数。采用实测资料对文中所得结论进... 详细信息

在经典力学的基础上 ,以某一概率作为定量起动标准。考虑到床面颗粒的相互隐暴影响 ,引入了等效粒径来研究泥沙的起动条件。推导了斜面上非均匀沙的起动条件。计算得到了泥沙起动时临界无量纲切应力参数。采用实测资料对文中所得结论进行了验证。

关键词：河流动力学泥沙起动理论探讨斜坡非均匀沙冲积河床

雅砻江锦屏大河湾减水河段中鱼类栖息地模拟研究

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水电能源科学 2011年第3期29卷 40-43页

作者：谭燕平王玉蓉李嘉刘敏四川大学水力学与山区河流开发保护国家重点实验室四川成都610065

针对引水式电站的修建将造成坝下河道减脱水、危害减水河段内水生生物生存的问题,以雅砻江锦屏大河湾猫猫滩闸址至九龙河汇口36km减脱水河段为例,选取了1.75km的浅滩和2.12.m的深潭生境河段作为鱼类栖息地评价的特征河段,采用单变量方法... 详细信息

针对引水式电站的修建将造成坝下河道减脱水、危害减水河段内水生生物生存的问题,以雅砻江锦屏大河湾猫猫滩闸址至九龙河汇口36km减脱水河段为例,选取了1.75km的浅滩和2.12.m的深潭生境河段作为鱼类栖息地评价的特征河段,采用单变量方法,在前人研究的基础上结合特征河段自然生境水力学特点,分析得出目标物种对水深及流速的适宜性曲线。并采用河道内流量增加法,建立了雅砻江锦屏大河湾特征河段鱼类栖息地模拟的river2.模型,确定了特征河段中目标物种适宜的栖息地面积变化情况,定性描述了鱼类适宜栖息地分布随流量变化的关系。研究结果表明,鱼类适宜栖息地随流量增大将由河道中间逐渐向边缘移动;在小流量时鱼类适宜栖息地面积增长迅速,随流量的进一步增大鱼类适宜栖息地增长速率明显减缓甚至基本不变,且当流量大于一定值时将会呈现负增长。

关键词：河道内流量增量法适宜性曲线 river2.模式适宜栖息地面积雅砻江锦屏大河湾

Conditions of Incipient Motion of Pebbles Based on Shape and the Equivalent Grain Size

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Conditions of Incipient Motion of Pebbles Based on Shape and...