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Finite element and experimental analysis of pinion bracket-assembly of three gorges project ship lift 被引量:2
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作者 石端伟 汪勇波 +2 位作者 彭惠 赵铁柱 程术潇 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第4期1307-1314,共8页
The pinion bracket-assembly(PBA) is a major part of three gorges project(TGP) ship lift drive system. The static strength,fatigue strength and stress distribution of hinge pin of PBA were analyzed by ANSYS, and the st... The pinion bracket-assembly(PBA) is a major part of three gorges project(TGP) ship lift drive system. The static strength,fatigue strength and stress distribution of hinge pin of PBA were analyzed by ANSYS, and the structure of PBA was optimized. The results show that after the optimization, the maximum comprehensive stress is 259.59 MPa, the maximum fatigue cumulative damage of weld joints is 0.94 and the maximum vertical deformation of hinge pin is 0.14 mm. The elastic deformation, hydropneumatic spring cylinder(HSC) load response and the vibration characteristics of PBA were studied by the bearing test when PBA bore the load caused by different water level errors. The results indicate that when the water level of ship chamber ranges from 3.4 m to 3.6 m,the vertical elastic deformation of the pinion shaft is between-8.58 and 10.50 mm. When upward outage-load(1580 k N) is imposed by the test-rack, the vertical elastic deformation of the pinion shaft is 13.42 and 14.07 mm and HSC load response is 795.80-800.80 k N. In the process of imposing load on the pinion by the test-rack, the maximum vibration amplitude and acceleration of PBA internal components are 0.37° and 2.67 rad/s2, respectively; the maximum impact on the pin caused by vibration is 19.89 k N; the pinion shaft vertical displacement and HSC load response do not fluctuate. There is a great difference between the frequency of meshing force of the pinion and the rack(1.06 Hz) and first-order natural frequency of PBA(8.41 Hz), thus PBA will not resonate.From all above, PBA meets the static strength and fatigue strength requirements. The vibration of PBA internal components has no effect on the vertical displacement of the pinion shaft, HSC load response and smooth operation of PBA. There is a liner relationship in the ratio of 2:1 between the thrust imposed by the test-rack and HSC load, thus HSC can limit the load imposed on the pinion. 展开更多
关键词 three gorges project ship lift pinion bracket-assembly FEM fatigue strength structure optimization vibration
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Incipient Motion of Bed Load Sediment and Its Application in the Three Gorges Hydro Project
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作者 HE Wenshe~(1,3) CAO Shuyou~2 YUAN Jie~3 DAI Huichao~3 (1.Lanzhou Jiao Tong Univ.,Lanzhou 730070,China 2.State Key Lab.of Hydraulics and Mountain River Eng.,Sichuan Univ.,Chengdu 610065,China 3.China Yangtze Three Gorges Project Development Corporation,Hubei Yichang 443002,China) 《四川大学学报(工程科学版)》 EI CAS CSCD 北大核心 2005年第S1期102-105,共4页
A formula for the calculation of critical shear stress of non-uniform sediment was developed by on river bed has been established while considering the relative degree expose of grains.The values of the Coeffi- cients... A formula for the calculation of critical shear stress of non-uniform sediment was developed by on river bed has been established while considering the relative degree expose of grains.The values of the Coeffi- cients in the formula have been obtained.The formula has been verified with prototype observation data, flumes data of both nature and lightweight sand.The computed results fully reflect the characteristics of thresh- old motion of non-uniform sediment.The result have been used in some physical mo... 展开更多
关键词 non-uniform sediment incipient motion bed load Three gorges Hydro project
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A Comparative Overview of Three Gorges Project's Sediment Handling
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作者 CHEN Ji-shengProfessor-senior Engineer, PhD, Director Emeritus, Yangtze River Scientific Research Institute, Wuhan 430010, Hubei 《人民长江》 北大核心 2002年第S1期22-27,共6页
Water projects’ sediment deposition problems always cause widespread concerns. The gravity of them varies in accordance not only with reservoirs’ natural and socio-economic characteristics but also with their modes ... Water projects’ sediment deposition problems always cause widespread concerns. The gravity of them varies in accordance not only with reservoirs’ natural and socio-economic characteristics but also with their modes of operation. The unique characteristics, configuration and mode of operation of Three Gorges Project (TGP) reservoir are compared with those of several existing large reservoirs in this paper. As many reservoirs are troubling environment by gradually extending coarse sediment deposition at the uppermost end of fluctuating backwater region toward upstream, Gezhouba reservoir on Yangtze and Danjiangkou reservoir on Hanjiang have shown no trace of such upstream extension of sediment deposition in relevant prototype observation data for the past 20 and more years. TGP reservoir’s in-coming flow sediment conditions and configuration in plane are almost the same as those of Gezhouba reservoir, and TGP reservoir’s mode of operation(usually keeping a very low pool level for flood control in flood season and storing up in-coming flow only thenceafter) is similar to that of Danjiangkou reservoir. New findings of sediment research and prototype flow sediment investigations as well as new agenda of large hydro projects’ construction on Jinshajiang in nearest future assure the prospects of TGP sediment handling. 展开更多
关键词 Three gorges project SEDIMENT HANDLING reservoir’s CONFIGURATION reservoir’s mode of operation
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Projective synchronization control and simulation of drive system and response network
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作者 LI De-kui 《兰州大学学报(自然科学版)》 北大核心 2025年第2期208-214,共7页
Projective synchronization problems of a drive system and a particular response network were investigated,where the drive system is an arbitrary system with n+1 dimensions;it may be a linear or nonlinear system,and ev... Projective synchronization problems of a drive system and a particular response network were investigated,where the drive system is an arbitrary system with n+1 dimensions;it may be a linear or nonlinear system,and even a chaotic or hyperchaotic system,the response network is complex system coupled by N nodes,and every node is showed by the approximately linear part of the drive system.Only controlling any one node of the response network by designed controller can achieve the projective synchronization.Some numerical examples were employed to verify the effectiveness and correctness of the designed controller. 展开更多
关键词 pinning control projective synchronization drive system response network
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REMOTE SESING INVESTIGATION AND APPRAISAL OF LAND USE AND CAPACITY IN THE REGION OF THE YANGTZE RIVER GORGES’PROJECT
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作者 Zhou Wancun (Chengdu Institue of Mountain Dissaster and Environment, Chinese Academy of Sciences) 《遥感信息》 CSCD 1990年第A02期43-44,共2页
The region around the Three Gorges project on the Yangtze River has an area of 62552 square kilometres and population of 20.14 million. It limits a range hetween the sorth-north watersheds and from Yichang of Hubei Pr... The region around the Three Gorges project on the Yangtze River has an area of 62552 square kilometres and population of 20.14 million. It limits a range hetween the sorth-north watersheds and from Yichang of Hubei Province to Jiangjin of Sichuan, including 24 cities and counties-Chongjing, Yichang and Wanxian etc. In this region, relief are mainly hills and middle-low mountains. Remote censing investigation and appraisal of land use and capacity which are two of the major restrict factors for the Three Gorges project have provided related scientific bases for macro-dicision-making of the project. 展开更多
关键词 project REMOTE SESING INVESTIGATION AND APPRAISAL OF LAND USE AND CAPACITY IN THE REGION OF THE YANGTZE RIVER gorges
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Current status and diversity of fish resources in the Pinglu Canal Century Project
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作者 LU Jia TANG Wei +3 位作者 WANG Li XU Shengxian ZHANG Peng YANG Shengfa 《水利水电技术(中英文)》 北大核心 2025年第4期131-144,共14页
[Objective]The channel straightening project of the Pinglu Canal has fragmented the river course,compromising the integrity of original river course and causing ecosystem patchiness.Understanding the current status of... [Objective]The channel straightening project of the Pinglu Canal has fragmented the river course,compromising the integrity of original river course and causing ecosystem patchiness.Understanding the current status of fish resources and the characteristics of their diversity is crucial for the ecological management of the Pinglu Canal.[Methods]During the spring and autumn in 2021 and 2022,a survey of fish resources and species diversity in the Pinglu Canal was conducted using multi-mesh gill nets.A total of 125 fish species were collected,belonging to 10 orders,34 families,and 89 genera.[Results]The result showed that the Pinglu Canal contained three nationally protected Class II species,two endemic species of the Qinjiang River,three anadromous/migratory species,and eight invasive species,accounting for 2.4%,1.6%,2.4%,and 6.4%of the total species,respectively.The fish community primarily consisted of mid-and bottom-dwelling,adhesive-egg-laying,and omnivorous species.The Shannon-Wiener,Simpson,Margalef,and Pielou indices of the fish community in the Pinglu Canal ranged from 2.347 to 2.757,0.081 to 0.151,3.493 to 4.382,and 0.812 to 0.892,respectively.These indices showed relatively uniform distribution across different river reaches.[Conclusion]The result indicate that the fish community structure in the Pinglu Canal is relatively uniform.The reach from the Yujiang River to the Shaping River shows higher stability,while other river reaches experience moderate or severe disturbances.This study provides supplementary baseline data on the fish community structure in the Pinglu Canal and explores the potential impact of inter-basin connectivity on fish resources,aiming to provide a scientific basis for habitat restoration assessments after the channel straightening project. 展开更多
关键词 Pinglu Canal project inter-basin connectivity fish resources community structure BIODIVERSITY influencing factors
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微项目化学习在人教版初中英语新教材中的实施路径——以Project板块为例
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作者 吕勇民 《中小学英语教学与研究》 北大核心 2025年第1期72-76,共5页
2024年版人民教育出版社《义务教育教科书·英语》七年级上册每个单元新增了Project学习板块。本研究根据Project板块在单元教学内容编排体系中的定位,探讨了在该板块开展微项目化学习的价值和可行性,并通过课例展示了微项目化学习... 2024年版人民教育出版社《义务教育教科书·英语》七年级上册每个单元新增了Project学习板块。本研究根据Project板块在单元教学内容编排体系中的定位,探讨了在该板块开展微项目化学习的价值和可行性,并通过课例展示了微项目化学习的实施路径,即学生在真实情境中发现问题,通过小组合作分解问题,在探索实践中解决问题,接着相互交流分享心得并评价作品,进而对作品升级迭代,再自评参与表现,最终实现素养发展。希望能以此促进课堂教学方式转变,提升教学效能。 展开更多
关键词 初中英语 新教材 project板块 微项目化学习
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Knowledge graph construction and complementation for research projects
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作者 LI Tongxin LIN Mu +2 位作者 WANG Weiping LI Xiaobo WANG Tao 《Journal of Systems Engineering and Electronics》 2025年第3期725-735,共11页
Tracking and analyzing data from research projects is critical for understanding research trends and supporting the development of science and technology strategies.However,the data from these projects is often comple... Tracking and analyzing data from research projects is critical for understanding research trends and supporting the development of science and technology strategies.However,the data from these projects is often complex and inadequate,making it challenging for researchers to conduct in-depth data mining to improve policies or management.To address this problem,this paper adopts a top-down approach to construct a knowledge graph(KG)for research projects.Firstly,we construct an integrated ontology by referring to the metamodel of various architectures,which is called the meta-model integration conceptual reference model.Subsequently,we use the dependency parsing method to extract knowledge from unstructured textual data and use the entity alignment method based on weakly supervised learning to classify the extracted entities,completing the construction of the KG for the research projects.In addition,a knowledge inference model based on representation learning is employed to achieve knowledge completion and improve the KG.Finally,experiments are conducted on the KG for research projects and the results demonstrate the effectiveness of the proposed method in enriching incomplete data within the KG. 展开更多
关键词 research projects knowledge graph(KG) KG completion
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Construction of Thin Concrete Lined Walls for Three Gorges Shiplock
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作者 MA Yu-zengEngineer, Three Gorges Project Command of Armed Police Hydropower Engineering Troops,Yichang 443133,China 《人民长江》 北大核心 2002年第S1期32-35,共4页
With high rock slope in shiplock area, thin reinforced concrete lining walls are constructed for the shiplock system. The construction technology involves much complicated structures in formwork, frequent interference... With high rock slope in shiplock area, thin reinforced concrete lining walls are constructed for the shiplock system. The construction technology involves much complicated structures in formwork, frequent interference due to crossover working procedures, tight time schedule, high quality of reinforced concrete and showcase appearance requirements, hidden troubles affecting construction safety. With above-mentioned factors in consideration, a single-side-separated sliding formwork technology advanced from past sliding formwork experiences has been developed and applied successfully. This new technology is beneficial in quick and safe operation, capable to assure best quality and appearance of shiplock concrete works, and has filled up the gap in terms of construction sliding formwork in our country. 展开更多
关键词 THIN lined WALL shiplock CHAMBER SLIDING form CONSTRUCTION technology Three gorges MULTI-PURPOSE project
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Paleoenvironmental Records of Calcrete in the Three Gorges of Yichang,China
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作者 Baohua Wei,Shangbin Xiao,Jiacheng Zhao Three Gorges University,Yichang 443002,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期117-117,共1页
Calcretes occur in a number of locations across the Yangtze Three Gorges in Yichang,central China. They represent the phase of Quaternary calcium carbonate cementation affected by the East Asian monsoon region.Calcret... Calcretes occur in a number of locations across the Yangtze Three Gorges in Yichang,central China. They represent the phase of Quaternary calcium carbonate cementation affected by the East Asian monsoon region.Calcretes are situated at the relict fluvial terrace that were deposited within confined bedrock and limestone soil.Eight samples from separate terrace were singled out and dated by ESR. 展开更多
关键词 CALCRETES SEM PALAEOCLIMATE YANGTZE Three gorges
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Prediction of Hydraulic Stability of Francis Turbines of Three Gorges Hydropower Station
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作者 TIAN Zi qinSenior Engineer, Design Institute, Changjiang Water Resources Commission, Wuhan 430010,China LIU Jing wang Professor, Design Institute, Changjiang Water Resources Commission, Wuhan 430010,China 《人民长江》 北大核心 2001年第S1期5-9,共5页
The Francis turbine of Three Gorges hydropower station is one of the large turbines with great head variation in the world. The operational stability of the turbine has been the top subject for departments of design, ... The Francis turbine of Three Gorges hydropower station is one of the large turbines with great head variation in the world. The operational stability of the turbine has been the top subject for departments of design, research, manufacture and operation to be concerned about. During the course of preparing bid invitation documents and executing the contract for the Three Gorges left power plants turbogenerator units, the hydraulic stability of the turbine was regarded as the most important problem and specific stability indexes of the model turbine and the prototype turbine were respectively specified in the contract. In the model tests for turbine model acceptance, pressure fluctuation phenomena in the case of partial load were found to be different from the usual ones as people had known. Within the range of operating water head, there existed a peak value zone of pressure fluctuations with higher frequencies, and large amplitude pressure fluctuations simultaneously occurred in several localities from the spiral case entrance to the draft tube. On the basis of test results from the model, the influence of cavitation coefficient and aeration on pressure fluctuations is analyzed, and some measures to improve the hydraulic stability of turbines of Three Gorges hydropower station are expounded. 展开更多
关键词 FRANCIS TURBINE HYDRAULIC stability PRESSURE FLUCTUATION model test Sanxia Multipurpose project
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APPLICATIONS OF REMOTE SENSING IN ENVIRONMENTAL INVESTIGATION AND CHANGE ANALYSIS IN THE THREE GORGES AREA
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作者 Chen Yu, Huang Xueqiao (Institute of Mountain Disaster and Environment, the Chinese Academy of Sciences and Ministry of Water Conservancy, Chengdu) 《遥感信息》 CSCD 1990年第A02期23-24,共2页
1. INTRODUCTION The proposed Three Gorges Project, one of the biggest hydroelectric projects in the world, will dam the middle reaches of the Changjiang (Yangtze) River, the third longest river in the world, and form ... 1. INTRODUCTION The proposed Three Gorges Project, one of the biggest hydroelectric projects in the world, will dam the middle reaches of the Changjiang (Yangtze) River, the third longest river in the world, and form a large reservoir. Its impacts on environment have attracted wide attention. Entrusted by National Scientific-Technical Commission, the Chinese Academy of Sciences (CAS) was in charge of a research project on this issuse from 1984 to 1989. Tho use of remote sensing played an important role in the project considering the study area is mountainous and not convenientlv located, which makes it difficult to conduct the research onlv using conventional means. 展开更多
关键词 DATA APPLICATIONS OF REMOTE SENSING IN ENVIRONMENTAL INVESTIGATION AND CHANGE ANALYSIS IN THE THREE gorges AREA
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Water Environmental Issue in Three Gorges Reservoir Area and Its Protective Countermeasures
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作者 LI Xiao-kun 《水土保持研究》 CSCD 北大核心 2007年第4期19-23,共5页
关键词 三江源地区 水环境 水污染 保护对策
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Progress of Taiji-2 Project
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作者 LUO Ziren ZHANG Min +1 位作者 WANG Jianyu WU Yueliang 《空间科学学报》 CAS CSCD 北大核心 2024年第4期674-676,共3页
Taiji-2 project is the second step of Taiji program,which is to verify the required technology for Taiji-3 mission.The feasibility study of Taiji-2 is successfully finished,and some of the main progress is introduced ... Taiji-2 project is the second step of Taiji program,which is to verify the required technology for Taiji-3 mission.The feasibility study of Taiji-2 is successfully finished,and some of the main progress is introduced here. 展开更多
关键词 Gravitational wave Taiji program Taiji-2 project
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Construction and Research Progress of the Chinese Meridian Project in 2022–2023
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作者 WANG Chi CHEN Zhiqing XU Jiyao 《空间科学学报》 CAS CSCD 北大核心 2024年第4期704-711,共8页
The Chinese Meridian Project(CMP)is a major national science and technology infrastructure constructed in two steps.The first phase of the CMP has been operating for more than a solar cycle.From 2022 to 2023,utilizing... The Chinese Meridian Project(CMP)is a major national science and technology infrastructure constructed in two steps.The first phase of the CMP has been operating for more than a solar cycle.From 2022 to 2023,utilizing the monitoring data collected by the CMP,scientists made major breakthroughs in fields of ionosphere,middle and upper atmosphere,and coupling between layers.The construction of the second phase of the CMP is nearly finished,and the project is expected to operate as a whole in 2025 after national acceptance of the second phase.The whole project was built in an architecture of so-called“One Chain,Three Networks and Four Focuses”.It is promising to make a three-dimensional observation of the whole solar-terrestrial space.The science community is looking forward to the great contribution of the CMP to space weather and space physics research. 展开更多
关键词 Chinese Meridian project(CMP) MAGNETOSPHERE IONOSPHERE Middle and upper atmosphere
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A process monitoring method for autoregressive-dynamic inner total latent structure projection
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作者 CHEN Yalin KONG Xiangyu LUO Jiayu 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第5期1326-1336,共11页
As a dynamic projection to latent structures(PLS)method with a good output prediction ability,dynamic inner PLS(DiPLS)is widely used in the prediction of key performance indi-cators.However,due to the oblique decompos... As a dynamic projection to latent structures(PLS)method with a good output prediction ability,dynamic inner PLS(DiPLS)is widely used in the prediction of key performance indi-cators.However,due to the oblique decomposition of the input space by DiPLS,there are false alarms in the actual industrial process during fault detection.To address the above problems,a dynamic modeling method based on autoregressive-dynamic inner total PLS(AR-DiTPLS)is proposed.The method first uses the regression relation matrix to decompose the input space orthogonally,which reduces useless information for the predic-tion output in the quality-related dynamic subspace.Then,a vector autoregressive model(VAR)is constructed for the predic-tion score to separate dynamic information and static informa-tion.Based on the VAR model,appropriate statistical indicators are further constructed for online monitoring,which reduces the occurrence of false alarms.The effectiveness of the method is verified by a Tennessee-Eastman industrial simulation process and a three-phase flow system. 展开更多
关键词 dynamic characteristic fault detection feature extraction process monitoring projection to latent structure(PLS) quality-related spatial partitioning
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Evaluating Vegetation Health Condition Using MODIS Data in the Three Gorges Area, China
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作者 韩贵锋 谢雨丝 蔡智 《西部人居环境学刊》 2015年第2期121-132,共12页
The satellite-based vegetation condition index(VCI) and temperature condition index(TCI) have been used extensively for drought detection and tracking, the assessment of weather impacts on vegetation and evaluation of... The satellite-based vegetation condition index(VCI) and temperature condition index(TCI) have been used extensively for drought detection and tracking, the assessment of weather impacts on vegetation and evaluation of the health and productivity of vegetation. In this study, in order to detect and monitor the growth condition of vegetation, we have collected data on vegetation indices and land surface temperature derived from MODIS(2001-2012) and defined a vegetation health index(VHI) based on VCI and TCI for assessing vegetation health condition in the Three Gorges Area, China(TGA). The results of the study show that temporal and spatial characteristics of vegetation health condition can be detected, tracked and mapped by the VHI index. In most parts of the TGA, the vegetation health condition showed an overall increasing trend during the study period, especially in Wulong, Fengdu, Shizhu and other regions located in the midstream sections of the Three Gorges Reservoir. In addition, the four studied vegetation types all showed clear increasing trends during the study period. The increasing trend in the vegetation health condition shows a strong positive correlation with topographical slope and altitude(below 500 m). Over the seasons, this trend is strongest in autumn, followed by spring. However, the correlations between vegetation health condition and climatic factors are more frequently significant in summer and winter than in autumn and spring. The vegetation health condition has been low in 2006 and 2011. This finding is consistent with the extreme weather conditions in those two years. However, only in the summer is vegetation health condition significantly correlated with three climatic factors in most of the study area. This result implies that vegetation growth may show a lagged response to climatic factors and may also be affected by human activities, including agricultural activities, industrial activities and other economic activities. 展开更多
关键词 人居环境 城市规划 建筑设计 园林设计
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三峡枢纽泄洪建筑物泄流能力复核研究 被引量:1
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作者 胡晗 耿峻 +1 位作者 童广勤 丁宇 《长江科学院院报》 北大核心 2025年第1期115-119,128,共6页
三峡大坝自2003年建库蓄水以来,泄洪消能建筑物经历了多场大洪水考验。为进一步总结三峡泄洪消能建筑物设计及实际运行情况,在三峡水利枢纽大坝安全首次定期检查期间,对三峡工程的泄流能力进行了全面复核。通过黄陵庙水文站实测数据复... 三峡大坝自2003年建库蓄水以来,泄洪消能建筑物经历了多场大洪水考验。为进一步总结三峡泄洪消能建筑物设计及实际运行情况,在三峡水利枢纽大坝安全首次定期检查期间,对三峡工程的泄流能力进行了全面复核。通过黄陵庙水文站实测数据复核了电站机组过机流量曲线,实测电站出流数据表明,水轮机出力曲线计算得出的左岸电站、右岸电站和地下电站机组流量均能准确反映真实的电站过机流量。复核了深孔和表孔的实际泄流能力,并和设计值与模型试验值进行了对比,通过对比可知,深孔实测泄流能力和设计值相当;表孔实测泄流能力,较设计值略微偏大;深孔和表孔实测联合泄流能力和设计值基本一致。 展开更多
关键词 三峡枢纽 深孔 表孔 泄流能力
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巫山段岸坡水岩劣化特征及危岩失稳破坏模式 被引量:1
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作者 刘新荣 罗新飏 +4 位作者 郭雪岩 周小涵 王浩 许彬 郑颖人 《工程地质学报》 北大核心 2025年第1期240-257,共18页
消落带干湿循环,江水、地下水的渗流、溶蚀等现象表明三峡库区长期处于频繁的水活动环境中。在复杂的水文地质环境下,巫山段岸坡内形成多处危岩体,存在较大发生地质灾害的可能性。本文主要对三峡库区巫山段岸坡危岩进行了实地调研,结合... 消落带干湿循环,江水、地下水的渗流、溶蚀等现象表明三峡库区长期处于频繁的水活动环境中。在复杂的水文地质环境下,巫山段岸坡内形成多处危岩体,存在较大发生地质灾害的可能性。本文主要对三峡库区巫山段岸坡危岩进行了实地调研,结合调研结果与地质资料,明确了该段内的水岩劣化特征、岸坡危岩分布及类型、危岩稳定性影响因素和失稳破坏模式。结果表明,段内消落带具有明显的水岩物理、化学、应力劣化特征,且3类水岩作用共同影响着消落带的形态、强度以及岸坡的稳定性。巫山段岸坡危岩的形成主要受到地质结构因素、环境因素与时间效应的综合影响,危岩类型可概化为塔柱状、板状、楔形状、排柱状4类。岸坡危岩稳定性关键影响因素主要为消落带岩体劣化、软弱夹层、后缘深大裂隙、库水诱发地震与其他环境因素,与水岩劣化作用联系紧密。提出了4类岸坡危岩失稳破坏模式:基座溃屈型、滑移型、倾倒型(渐进倾倒)、溶蚀坠落型,并对巫山段岸坡危岩的防治措施提出一定的建议。 展开更多
关键词 三峡库区 岸坡危岩 水岩劣化 失稳破坏 灾害防治
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基于时序InSAR技术的木鱼包滑坡时空变形特征分析 被引量:1
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作者 刘艺梁 樊西丰 +4 位作者 申高伟 左清军 唐玄 李永奕 朱前 《地质科技通报》 北大核心 2025年第2期78-93,共16页
自2003年三峡库区蓄水以来,木鱼包滑坡持续变形,严重威胁长江航运和库区人民生命财产安全。为全面精准地分析滑坡地表变形信息,采用斯坦福永久散射体-多时相InSAR(StaMPS-MTI)技术和短基线集时序InSAR(SBAS-InSAR)技术结合哨兵一号数据... 自2003年三峡库区蓄水以来,木鱼包滑坡持续变形,严重威胁长江航运和库区人民生命财产安全。为全面精准地分析滑坡地表变形信息,采用斯坦福永久散射体-多时相InSAR(StaMPS-MTI)技术和短基线集时序InSAR(SBAS-InSAR)技术结合哨兵一号数据反演木鱼包滑坡2017-2022年的地表形变,并与全球导航卫星系统(GNSS)监测数据进行对比分析,结合2种技术的优点,点面结合对滑坡的时空变形特征进行了分区研究。研究结果表明:InSAR技术得到的形变信息可靠,2种时序InSAR技术各有优劣;对比各个分区的形变速率区间值,滑坡东侧坡面(-30.6~-46.2 mm/a)>主滑面东侧(-25.2~-37.8 mm/a)>主滑面西侧(-21.5~-31.5 mm/a)。在InSAR形变结果和前人研究基础上,对木鱼包滑坡变形模式进行了总结:木鱼包滑坡变形受降雨和库水影响,分为整体变形和局部变形2种。在高水位运行期,滑坡受浮托减重作用发生整体变形,库水阈值约为168 m。强降雨入渗岩体使地下水位升高,促使整体变形的同时,影响浅层土体和破碎岩体导致局部变形。在库水位下降期,滑坡受浮托减重和动水压力共同影响,其中浮托减重作用占主导地位,动水压力存在约36 d的滞后时间。在低水位运行期和库水位上升期,整体变形停止,强降雨使局部变形区发生变形。研究结果证明时序InSAR技术可以有效识别和监测滑坡,可以为地质灾害防治、风险评价提供技术支撑。 展开更多
关键词 木鱼包滑坡 形变监测 SBAS-InSAR StaMPS-MTI 三峡库区 库水位 降雨
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