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Gorging Online
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作者 Pride Phiri 《ChinAfrica》 2011年第2期57-57,共1页
MY introduction to social networking came in my first year of university.I had never been online before then nor used a computer extensively. The archaic machines at my high school had been good for a few rounds of so... MY introduction to social networking came in my first year of university.I had never been online before then nor used a computer extensively. The archaic machines at my high school had been good for a few rounds of solitaire and nothing more.Growing up in Zimbabwe at the turn of the century where even cell phones were a novelty,the Internet was just something you read about and then added to the list of things that while nice to have,didn’t really factor into everyday life. 展开更多
关键词 FACEBOOK gorging Online
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Projecting Spring Consecutive Rainfall Events in the Three Gorges Reservoir Based on Triple-Nested Dynamical Downscaling 被引量:2
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作者 Yanxin ZHENG Shuanglin LI +2 位作者 Noel KEENLYSIDE Shengping HE Lingling SUO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1539-1558,共20页
Spring consecutive rainfall events(CREs) are key triggers of geological hazards in the Three Gorges Reservoir area(TGR), China. However, previous projections of CREs based on the direct outputs of global climate model... Spring consecutive rainfall events(CREs) are key triggers of geological hazards in the Three Gorges Reservoir area(TGR), China. However, previous projections of CREs based on the direct outputs of global climate models(GCMs) are subject to considerable uncertainties, largely caused by their coarse resolution. This study applies a triple-nested WRF(Weather Research and Forecasting) model dynamical downscaling, driven by a GCM, MIROC6(Model for Interdisciplinary Research on Climate, version 6), to improve the historical simulation and reduce the uncertainties in the future projection of CREs in the TGR. Results indicate that WRF has better performances in reproducing the observed rainfall in terms of the daily probability distribution, monthly evolution and duration of rainfall events, demonstrating the ability of WRF in simulating CREs. Thus, the triple-nested WRF is applied to project the future changes of CREs under the middle-of-the-road and fossil-fueled development scenarios. It is indicated that light and moderate rainfall and the duration of continuous rainfall spells will decrease in the TGR, leading to a decrease in the frequency of CREs. Meanwhile, the duration, rainfall amount, and intensity of CREs is projected to regional increase in the central-west TGR. These results are inconsistent with the raw projection of MIROC6. Observational diagnosis implies that CREs are mainly contributed by the vertical moisture advection. Such a synoptic contribution is captured well by WRF, which is not the case in MIROC6,indicating larger uncertainties in the CREs projected by MIROC6. 展开更多
关键词 triple-nested downscaling Three Gorges Reservoir area consecutive rainfall events geological hazards PROJECTION
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Spatiotemporal deformation characteristics of Outang landslide and identification of triggering factors using data mining 被引量:1
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作者 Beibei Yang Zhongqiang Liu +1 位作者 Suzanne Lacasse Xin Liang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第10期4088-4104,共17页
Since the impoundment of Three Gorges Reservoir(TGR)in 2003,numerous slopes have experienced noticeable movement or destabilization owing to reservoir level changes and seasonal rainfall.One case is the Outang landsli... Since the impoundment of Three Gorges Reservoir(TGR)in 2003,numerous slopes have experienced noticeable movement or destabilization owing to reservoir level changes and seasonal rainfall.One case is the Outang landslide,a large-scale and active landslide,on the south bank of the Yangtze River.The latest monitoring data and site investigations available are analyzed to establish spatial and temporal landslide deformation characteristics.Data mining technology,including the two-step clustering and Apriori algorithm,is then used to identify the dominant triggers of landslide movement.In the data mining process,the two-step clustering method clusters the candidate triggers and displacement rate into several groups,and the Apriori algorithm generates correlation criteria for the cause-and-effect.The analysis considers multiple locations of the landslide and incorporates two types of time scales:longterm deformation on a monthly basis and short-term deformation on a daily basis.This analysis shows that the deformations of the Outang landslide are driven by both rainfall and reservoir water while its deformation varies spatiotemporally mainly due to the difference in local responses to hydrological factors.The data mining results reveal different dominant triggering factors depending on the monitoring frequency:the monthly and bi-monthly cumulative rainfall control the monthly deformation,and the 10-d cumulative rainfall and the 5-d cumulative drop of water level in the reservoir dominate the daily deformation of the landslide.It is concluded that the spatiotemporal deformation pattern and data mining rules associated with precipitation and reservoir water level have the potential to be broadly implemented for improving landslide prevention and control in the dam reservoirs and other landslideprone areas. 展开更多
关键词 LANDSLIDE Deformation characteristics Triggering factor Data mining Three gorges reservoir
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Microplastics in sediment of the Three Gorges Reservoir:abundance and characteristics under different environmental conditions
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作者 Wang LI Bo ZU +2 位作者 Yiwei LIU Juncheng GUO Jiawen LI 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期101-112,共12页
Freshwater microplastic pollution is an urgent issue of global concern,and research on the distribution in reservoirs is lacking.We investigated the microplastic pollution levels in wet sediments collected from the Th... Freshwater microplastic pollution is an urgent issue of global concern,and research on the distribution in reservoirs is lacking.We investigated the microplastic pollution levels in wet sediments collected from the Three Gorges Reservoir,the largest reservoir of China.Results show that microplastics were ubiquitous in the sediments of the Three Gorges Reservoir,and their abundance ranged from 59 to 276 pp/kg(plastic particles per kg,dry weight).Economic development and total population were important factors affecting the spatial heterogeneity of microplastic abundance,and the contribution of large cities along the reservoir to microplastic pollution should be paid with more attention.Fibrous microplastics were the most abundant type of microplastic particles in reservoir sediments,whereas polystyrene,polypropylene,and polyamide were the main types of polymers.The apparent spatial heterogeneity in morphology and color of microplastics is attributed to different anthropogenic or landbased pollution sources.Moreover,the accumulation of microplastics near the inlet of tributaries reflects the role of potential contributors of tributaries.More importantly,multiple bisphenols(BPs)and heavy metals detected at the microplastic surfaces indicate that microplastics can act as carriers of these pollutants in the environment in the same way as sediments did,which may alter the environmental fate and toxicity of these pollutants.Therefore,we conclude that the Three Gorges Reservoir had been contaminated with microplastics,which posed a stress risk for organisms who ingest them along with their associated pollutants(BPs,heavy metals). 展开更多
关键词 microplastics Three Gorges Reservoir SEDIMENT BISPHENOL heavy metal
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Long-Term Performance and Microstructural Characterization of Dam Concrete in the Three Gorges Project
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作者 Chen Lyu Cheng Yu +3 位作者 Chao Lu Li Pan Wenwei Li Jiaping Liu 《Engineering》 SCIE EI CAS CSCD 2024年第2期237-262,共26页
This study investigates the long-term performance of laboratory dam concrete in different curing environments over ten years and the microstructure of 17-year-old laboratory concrete and actual concrete cores drilled ... This study investigates the long-term performance of laboratory dam concrete in different curing environments over ten years and the microstructure of 17-year-old laboratory concrete and actual concrete cores drilled from the Three Gorges Dam.The mechanical properties of the laboratory dam concrete,whether cured in natural or standard environments,continued to improve over time.Furthermore,the laboratory dam concrete exhibited good resistance to diffusion and a refined microstructure after 17 years.However,curing and long-term exposure to the local natural environment reduced the frost resistance.Microstructural analyses of the laboratory concrete samples demonstrated that moderate-heat cement and fine fly ash(FA)particles were almost fully hydrated to form compact micro structures consisting of large quantities of homogeneous calcium(alumino)silicate hydrate(C-(A)-S-H)gels and a few crystals.No obvious interfacial transition zones were observed in the microstructure owing to the longterm pozzolanic reaction.This dense and homogenous microstructure was the crucial reason for the excellent long-term performance of the dam concrete.A high FA volume also played a significant role in the microstructural densification and performance growth of dam concrete at a later age.The concrete drilled from the dam surface exhibited a loose microstructure with higher microporosity,indicating that concrete directly exposed to the actual service environment suffered degradation caused by water and wind attacks.In this study,both macro-performance and microstructural analyses revealed that the application of moderate-heat cement and FA resulted in a dense and homogenous microstructure,which ensured the excellent long-term performance of concrete from the Three Gorges Dam after 17 years.Long-term exposure to an actual service environment may lead to microstructural degradation of the concrete surface.Therefore,the retained long-term dam concrete samples need to be further researched to better understand its microstructural evolution and development of its properties. 展开更多
关键词 Three Gorges Dam Long-term performance Microstructural analysis Moderate-heat cement Fly ash
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Climate state of the Three Gorges Region in the Yangtze River basin in 2022–2023
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作者 Tong Cui Xianyan Chen +3 位作者 Xukai Zou Linhai Sun Qiang Zhang Hongling Zeng 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第5期61-66,共6页
Based on daily observation data of the Three Gorges Region(TGR)of the Yangtze River basin and global reanalysis data,the climate characteristics,climate events,and meteorological disasters of the TGR in 2022 and 2023 ... Based on daily observation data of the Three Gorges Region(TGR)of the Yangtze River basin and global reanalysis data,the climate characteristics,climate events,and meteorological disasters of the TGR in 2022 and 2023 were analyzed.For the TGR,the average annual temperature for 2022 and 2023 was 0.8℃ and 0.4℃ higher than normal,respectively,making them the two warmest years in the past decade.In 2022,the TGR experienced its warmest summer on record.The average air temperature was 2.4℃ higher than the average,and there were 24.8 days of above-average high temperature days during summer.Rainfall in the TGR varied significantly between 2022 and 2023.Annual rainfall was 18.4%below normal and drier than normal in most parts of the region.In contrast,the precipitation in 2023 was considerably higher than the long-term average,and above normal for almost the entire year.The average wind speed exhibited minimal variation between the two years.However,the number of foggy days and relative humidity increased in 2023 compared to 2022.In 2022–2023,the TGR mainly experienced meteorological disasters such as extreme high temperatures,regional heavy rain and flooding,overcast rain,and inverted spring chill.Analysis indicates that the abnormal western Pacific subtropical high and the abnormal persistence of the eastward-shifted South Asian high were the two important drivers of the durative enhancement of record-breaking high temperature in the summer of 2022. 展开更多
关键词 Three Gorges Region Climate state Extreme high temperature Torrential summer rainfall Climate analysis
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Characteristics and influencing mechanisms of production-living-ecological space dynamics in the Three Gorges Reservoir Area(TGRA),Chongqing,China
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作者 ZHU Xinyi GAO Jinlong 《Regional Sustainability》 2024年第2期49-62,共14页
The Three Gorges Reservoir Area(TGRA)is an important ecological barrier in the Yangtze River Basin,China.Therefore,it is of great importance to understand the spatio-temporal variation and the driving factors of produ... The Three Gorges Reservoir Area(TGRA)is an important ecological barrier in the Yangtze River Basin,China.Therefore,it is of great importance to understand the spatio-temporal variation and the driving factors of production-living-ecological spaces for sustainable and high-quality development in the TGRA.This study investigated the dynamic variation of production-living-ecological spaces in the TGRA by employing land use data in 2000,2005,2010,2015,and 2018,and detected the influencing factors by using the Geographic detector(GeoDetector).Results implied that the structure and dynamic trajectories of production-living-ecological spaces in the TGRA varied in both horizontal and vertical directions,and the study area was dominated by ecological space.A spatial orientation towards the northeast was detected in the evolution of production-living-ecological spaces during 2000-2018.In terms of quantity,the transition from ecological space(grassland and woodland)to agriculture land accounted for the largest proportion from 2000 to 2018.However,the reverse transition from agriculture land to ecological space has increased since 2000 with the efforts of“Grain for Green”.In terms of temporal scale,there was a fluctuating trend in production space with the continuous expansion of living space,while ecological space showed an inverted U-shaped trend during 2000-2018.The dynamic pattern of production-living-ecological spaces in the TGRA was influenced by both physical and socio-economic variables as basic determinants and dominant driving factors,respectively.Finally,the harmonization and protection of production-living-ecological spaces still require policy-makers’efforts.This work may have potential in advancing our understanding about land use conflicts,and provide a reference for rational layout of spatial functions and the realization of sustainable development in the TGRA. 展开更多
关键词 Production-living-ecological spaces Functional transition Three Gorges Reservoir Area(TGRA) Physical and socio-economic variables Yangtze River
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三峡库区紫色土7Be剖面分布及季节变化 被引量:7
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作者 史忠林 文安邦 +1 位作者 严冬春 苏明 《山地学报》 CSCD 北大核心 2010年第6期674-679,共6页
7Be是一种宇宙成因放射性核素。由于其来源明确、半衰期短、测试相对容易,可用于<1a时间尺度内的环境过程示踪和定量研究。7Be在土壤中的剖面分布特征及其本底值是建立定量模型、估算侵蚀沉积速率和调查表土迁移过程的基础。对三峡... 7Be是一种宇宙成因放射性核素。由于其来源明确、半衰期短、测试相对容易,可用于<1a时间尺度内的环境过程示踪和定量研究。7Be在土壤中的剖面分布特征及其本底值是建立定量模型、估算侵蚀沉积速率和调查表土迁移过程的基础。对三峡库区为期1a的无扰动紫色土7Be浓度的测定结果表明,7Be主要分布于质量深度0~20.0kg/m2(0~1.5cm)的表层土壤,其中0~3.0kg/m2(0~2mm)的最表层7Be比活度最高,向下随深度增加呈指数减少,20.0kg/m2以下土层基本不含7Be。采样期间土壤7Be总面积活度介于172.4~328.6Bq/m2,平均246.1Bq/m2,并呈现春季最高,秋季最低;春夏高,秋冬低的季节性变化特征。植被截留可能是减少土壤7Be浓度的重要因素。 展开更多
关键词 三峡库区 紫色土 剖面分布 季节变化 Three Gorges Reservoir Region SEASONAL Variability 表层土壤 放射性核素 重要因素 时间尺度 迁移过程 浓度 比活度 过程示踪 分布特征 定量研究 定量模型 沉积速率 测定结果 变化特征
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Movement Properties of Pipe Flow Along Granite Slope of Three Gorges Area of Yangtze River in China 被引量:2
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作者 张洪江 史玉虎 +4 位作者 程云 盛前丽 肖辉杰 陈宗伟 常丹东 《Forestry Studies in China》 CAS 2002年第1期35-43,共9页
It is well known that, in most cases, soil water doesn't move in the form of laminar flow as described by Darcy law. Only when Reynolds number ( Re ) is no more than 10, does water movement follow Darcy law. A s... It is well known that, in most cases, soil water doesn't move in the form of laminar flow as described by Darcy law. Only when Reynolds number ( Re ) is no more than 10, does water movement follow Darcy law. A soil profile with 2 9 m long and 2 13 2 60 m deep was excavated on a lower slope located at Zigui County, Hubei Province, China. Field observation found that soil pipes were mainly distributed in the transient layer between horizon B with higher degree of granite weathering and horizon C with lower degree of granite weathering. At the foot of the slope, about 5 7 soil pipes per meter were observed along the vertical direction of the slope. The observed results, obtained by continuous observation of soil pipes and pipe flow processes at granite slope for many rainfall events, indicate that the relationship between velocity of pipe flow and hydraulic gradient along the pipe is parabolic rather than linear. Based on the investigated data of soil, landform, and land use etc., combined with observed data of pipe flow derived from many rainfall events, a pipe flow model was developed. For velocity V p, discharge Q p of pipe flow and radius r of soil pipe, great similarity was found between simulated and observed values. Particularly, the simulated length of soil pipes reflects the great difference among soil pipes as a result of its different position in the soil profile. The length values of 4 soil pipes were estimated to be 98 1%, 27 6%, 11 0% and 3 0% of the longest distance of the catchment, respectively. As a special case of water movement, soil pipe flow follows Darcy Weisbach law. Discharge of pipe flow is much greater than infiltration discharge in common. Only when the depth of groundwater is more than the diameter of soil pipe and water layer submerges soil pipes during rainfall, may pipe flow occur. Under these circumstances, discharge of pipe flow is directly proportional to the depth of groundwater. 展开更多
关键词 soil pipe pipe flow granite slope the Three Gorges area the Yangtze River pipe flow model
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不同补偿调度方式下三峡水库分期汛限水位控制 被引量:4
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作者 杨春花 许继军 董玲燕 《水力发电》 北大核心 2010年第8期15-18,共4页
在径流统计分析的基础上,确定三峡水库汛期分期,并分别研究了两种防洪补偿调度方式下的各分期汛限水位。初步分析结果认为,在满足原设计防洪安全要求的前提下,对荆江河段防洪补偿的调度方式,则三峡水库汛期汛前期汛限水位155 m,主汛期... 在径流统计分析的基础上,确定三峡水库汛期分期,并分别研究了两种防洪补偿调度方式下的各分期汛限水位。初步分析结果认为,在满足原设计防洪安全要求的前提下,对荆江河段防洪补偿的调度方式,则三峡水库汛期汛前期汛限水位155 m,主汛期汛限水位维持145 m不变,汛末期水库运行水位为155 m;对兼顾城陵矶地区防洪补偿的调度方式,则汛前期汛限水位151 m,主汛期汛限水位维持145 m不变,汛末期汛限水位为147 m。这样的分期控制汛限水位不仅可以满足防洪要求,而且可以提高洪水资源的利用率。 展开更多
关键词 补偿 调度方式 三峡水库 水位控制 Operation Different Three Gorges Reservoir Study 分期汛限水位 防洪 主汛期 汛末期 运行水位 汛前 汛期分期 统计分析 荆江河段 洪水资源 分析结果 分期控制
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三峡地下电站引水隧洞双曲无轨滑模研究 被引量:2
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作者 廖湘辉 章成 +2 位作者 万刚 刘欢 余健 《水力发电》 北大核心 2010年第8期54-55,71,共3页
三峡地下电站引水隧洞上弯段属高速高压水流区,衬砌混凝土质量要求高,空间结构特殊,施工难度大,所提出的双曲无轨滑模具有空间双曲结构特点,特设可旋转修补抹面平台,实现无轨滑升,无须接缝和混凝土衬砌表面处理,提高了施工质量,加快了... 三峡地下电站引水隧洞上弯段属高速高压水流区,衬砌混凝土质量要求高,空间结构特殊,施工难度大,所提出的双曲无轨滑模具有空间双曲结构特点,特设可旋转修补抹面平台,实现无轨滑升,无须接缝和混凝土衬砌表面处理,提高了施工质量,加快了施工进度,节约了成本,具有良好的经济效益,对同类型的工程施工技术提供了重要的参考价值。 展开更多
关键词 三峡地下电站 引水隧洞 双曲 无轨滑模 HYDROPOWER Station Three Gorges Tunnel Construction 混凝土衬砌 衬砌混凝土 质量要求 施工质量 施工难度 施工进度 施工技术 空间结构 经济效益 结构特点 高压水流 参考价值 表面处理
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Analysis of the Spatial Features of the Traditional Folk Houses in Three Gorges Region 被引量:1
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作者 周传发 《Journal of Landscape Research》 2011年第7期92-94,共3页
The spatial composition of natural environment and settlement in the Three Gorges region along the Yangtze River was analyzed from a macro perspective,which emphasized its characteristics of the interdependence among ... The spatial composition of natural environment and settlement in the Three Gorges region along the Yangtze River was analyzed from a macro perspective,which emphasized its characteristics of the interdependence among its buildings,landform and waterscape,between buildings and landscape,and integration of nature and human culture.Then the spatial features of folk houses were analyzed,while special attention was paid to its "upward","grey",and dynamic characteristics.The courtyard-type residence and stilted building in South China were taken as examples in order to explain their exterior spatial characteristics,and the interior spatial features were analyzed from the pursuit of courtyard layout,the preference of courtyard space and the emphasis of central room space.The paper exposed the builders' rational thinking about natural environment and living place conveyed through the traditional folk houses,as well as the practical value of this architectural style in the special natural environment of the Three Gorges region,and explained the artistic achievements from the integration of architecture and environment,aiming to provide references for the urban and living environment construction in this region during the "Post Three-Gorges Project Era". 展开更多
关键词 THREE Gorges FOLK houses SPATIAL FEATURES BUILDINGS
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Research of Cultivation Technology of Auricularia auricula-judae in Forest Lands in The Three Gorges in Chongqing
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作者 王正春 蒋海艳 +2 位作者 吕圣富 周飞 陈道静 《Agricultural Science & Technology》 CAS 2013年第8期1147-1149,共3页
[Objective] The aim was to help farmers in poverty-stricken area in Three Gorges Reservoir Region to get rid of poverty and become better off.[Method] The cultivation experiment of Auricularia auricula-judae with bass... [Objective] The aim was to help farmers in poverty-stricken area in Three Gorges Reservoir Region to get rid of poverty and become better off.[Method] The cultivation experiment of Auricularia auricula-judae with basswoods was conducted in Guocun town,Wanzhou district in Three Gorges Reservoir Region and new technologies were concluded in terms of selection of cultivation site,preparation of mushroom materials,cultivation technology and management to guide cultivation of Auricularia auricula-judae.[Result] The research broadens a new way for starveling farmer to be better off.[Conclusion] The research provides references for under-forest economy in surrounding forests. 展开更多
关键词 Three Gorges Reservoir Region Auricularia auricula-judae BASSWOOD Cultivation technology
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Climate Characteristics in Three Gorges Reservoir Area after Water Storage and Its Impact on the Production Potential
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作者 钟海玲 高荣 杨霞 《Meteorological and Environmental Research》 CAS 2010年第2期53-56,共4页
Based on the meteorological data from 33 stations of Three Gorges Reservoir from 1960 to 2008,climate yield of rice,corn and winter wheat and the changes of climatic potential productivity after water storage in Three... Based on the meteorological data from 33 stations of Three Gorges Reservoir from 1960 to 2008,climate yield of rice,corn and winter wheat and the changes of climatic potential productivity after water storage in Three Gorges Reservoir were calculated by the dynamic statistic model of crop growth.The results showed that the temperature in Three Gorges Reservoir was fluctuant decreased before late 1980s,and warmed rapidly after the late 1980s.The precipitation had little change before the late 1990s and had a slight decrease after the late 1990s.Sunshine hours were more in 1960s and 1970s,and then it changed little after 1980s.After water storage,the temperature increased in Three Gorges Reservoir as a whole.The precipitation decreased in the south of Three Gorges Reservoir,while it increased in the northwest of Three Gorges Reservoir.The sunshine hours were reduced except that in the vicinity of Dianjiang.After water storage,climatic potential productivity of rice decreased in the northwest and the northeast,while it increased in the south of Three Gorges Reservoir.The climatic potential productivity of corn decreased in the northeast and the southwest,but increased in the rest of Three Gorges Reservoir.The climatic potential productivity of winter wheat increased almost in total. 展开更多
关键词 Three Gorges Reservoir area Water storage Climatic potential productivity CHANGE China
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三峡工程二期围堰防渗墙材料快速检测及其力学指标早期预报
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作者 孙开畅 田斌 孙志禹 《水力发电》 北大核心 2010年第12期42-44,47,共4页
鉴于三峡二期围堰的重要性,对现场快速判断防渗墙墙体材料施工质量的试验方法提出了新的要求。根据拌和样,测定出柔性材料的原材料的实际下料数量。根据防渗墙墙体材料成型样的早期强度,提出了其力学指标的早期预报方法。该方法应用于... 鉴于三峡二期围堰的重要性,对现场快速判断防渗墙墙体材料施工质量的试验方法提出了新的要求。根据拌和样,测定出柔性材料的原材料的实际下料数量。根据防渗墙墙体材料成型样的早期强度,提出了其力学指标的早期预报方法。该方法应用于三峡二期围堰实际施工中,取得了良好的效果。 展开更多
关键词 三峡工程 二期围堰防渗 墙材料 快速检测 力学指标 早期预报 Three Gorges Project CUTOFF WALL Materials for Property Prediction 墙体材料 防渗墙 预报方法 早期强度 试验方法 施工质量 柔性材料 快速判断 材料成型 原材料
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技术差异下的跨国市场并购研究
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作者 吴俊杰 《管理工程学报》 CSSCI 2007年第2期106-109,共4页
本文研究了跨国公司在进入东道国时的进入模式选择问题:新设投资或并购现有的企业。假定东道国是寡头市场结构,在位企业面临比自身更高技术水平的跨国公司的进入。分析表明进入成本的差异和进入后市场的竞争状况影响外国企业的进入模式... 本文研究了跨国公司在进入东道国时的进入模式选择问题:新设投资或并购现有的企业。假定东道国是寡头市场结构,在位企业面临比自身更高技术水平的跨国公司的进入。分析表明进入成本的差异和进入后市场的竞争状况影响外国企业的进入模式选择。研究结果显示,在多数案例中进入者倾向于收购本地在位高科技企业,进而与本地较低技术企业形成双寡头竞争市场结构。研究同时还表明,外国企业会通过较低的定价战略把本地市场的在位企业挤出市场的可能性。 展开更多
关键词 跨国并购 Gorg模型 技术 企业 定价战略
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Assessment and Analysis of the Tourism Development Value of Folk House Resources in Three Gorges Area
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作者 周传发 《Journal of Landscape Research》 2009年第2期55-60,共6页
This study aimed to introduce the characteristics and value of folk house resources in Three Gorges area,analyze the influence and opportunities for the development of folk house resources in this area brought by the ... This study aimed to introduce the characteristics and value of folk house resources in Three Gorges area,analyze the influence and opportunities for the development of folk house resources in this area brought by the Three Gorge Project,and put forward the ideas and countermeasures for tourism development of folk house resources in Three Gorges area. 展开更多
关键词 THREE Gorges FOLK HOUSE RESOURCES CULTURE TOURISM
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Strategies for Safe Land Use of the Three Gorges Reservoir Area (Chongqing Section)——With the Restoration of Degraded Forest Landscapes as a Study Case
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作者 牟萍 《Journal of Landscape Research》 2010年第8期51-55,共5页
As a key for constructing ecologically safe scenery, forest landscape pattern in Chongqing Section of the Three Gorges has shown degradation, fragmentation and revision of varying degrees. To ensure normal and safe op... As a key for constructing ecologically safe scenery, forest landscape pattern in Chongqing Section of the Three Gorges has shown degradation, fragmentation and revision of varying degrees. To ensure normal and safe operation of the Three Gorges, and meet requirements of integrated development strategies for ecological and economic effects in Chongqing City on the ecological security of land use in Chongqing section of the Three Gorges, the following points should be attached more importance in making future strategies for an ecologically safe land use pattern with the restoration of degraded forest landscape as its starting point:a. Ecological effects and economic functions that can be supplied by forest landscape elements in different restoration patterns should be understood to obtain background effect of the ecological security pattern scenario of land use in the reservoir region; b. Relationship between restoration of degraded forest landscapes and serious ecological interference factors such as degradation background, artificial disturbance and engineering stress, should be simulated to figure out the influence of natural or artificial driving factors on landscape pattern, determine the future restoration mode for the degraded forest landscapes in the reservoir region, so as to facilitate the construction of great ecological-economic security pattern of the Three Gorges. The findings will provide scientific basis for the decision-making in building an ecologically safe land use pattern in the Three Gorges reservoir area (Chongqing), when using the degradation of forest landscape restoration as a carrier at present or in the future. Further, they will help realize the development goals of "Livable Chongqing, Expedite Chongqing, Forestry Chongqing, Safe Chongqing and Healthy Chongqing". 展开更多
关键词 LAND use Ecological-economic security Forest LANDSCAPE The Three Gorges reservoir region
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Revision of Water Function Division and Countermeasures for Water Resources Protection in Jiangjin District of Chongqing City in China
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作者 侯新 《Journal of Landscape Research》 2011年第12期54-57,70,共5页
According to the current situation and development planning of water resources in Jiangjin District of Three Gorge Reservoir Area at the upper reaches of Yangtze River,by combining with social needs,through the survey... According to the current situation and development planning of water resources in Jiangjin District of Three Gorge Reservoir Area at the upper reaches of Yangtze River,by combining with social needs,through the survey on pollution source and analysis of water quality,based on the Report of Water Function Division of Jiangjin District(2005) ,the adjustment and revision have been conducted on water function divisions,and corresponding protection targets and countermeasures for water resources have been proposed,so that the water function division can comply with the development situation of Jiangjin District,providing a reliable reference for the protection and reasonable utilization of water resources,enhancing the unified and effective supervision of water resources,promoting the sustainable use of water resources in Jiangjin District,and ensuring the sustainable development of regional society and environment. 展开更多
关键词 Three Gorges Reservoir Area Jiangjin DISTRICT WATER FUNCTION DIVISION WATER resources protection COUNTERMEASURES
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Preliminary Study on Early-warning System of Ecological Security in Water-Level-Fluctuating Zone (WLFZ) of Three Gorges Reservoir 被引量:2
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作者 郑磊 左太安 李月臣 《Agricultural Science & Technology》 CAS 2010年第5期159-164,共6页
The area,the scope as well as some ecological environment questions in Three Gorges Reservoir was briefly introduced. Then its early warning-system frame was preliminarily constructed,which includes ecological securit... The area,the scope as well as some ecological environment questions in Three Gorges Reservoir was briefly introduced. Then its early warning-system frame was preliminarily constructed,which includes ecological security dynamic monitoring,ecological security appraisal,ecological security forecast and ecological security decision-making management. The synthetic evaluation indicator system of the ecological security quality were initially established,which includes ecological environment pollution,land use and land cover change,geological hazard and epidemic outbreaks. At the same time,29 evaluating indicators were selected,divides into the basic factors,response factors and inducing factors,which need to be Real-time monitored. 展开更多
关键词 Ecological security Early warning system Fuzzy mathematics Three Gorges Reservoir Water-Level-Fluctuating Zone (WLFZ)
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