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Influential Factors of House-purchasing Intention in Work construction Sites among Migrant Workers with a Case of Investigations on 203 Migrant Workers from Jiangxi Province 被引量:2
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作者 刘文 王彦之 《Agricultural Science & Technology》 CAS 2015年第12期2881-2885,共5页
The research selected 13 factors from individual and family characters, construction site characters and work characters and analyzed the influences on the willingness of purchasing houses on construction sites with L... The research selected 13 factors from individual and family characters, construction site characters and work characters and analyzed the influences on the willingness of purchasing houses on construction sites with Logistic regression mod- el. The results showed that gender, age differences, personality, willingness on fami- ly land conversion, management of enterprises on construction sites, relatives and friends on construction lands, and Job satisfaction were approved by significant testing, but marital status, annual household income, the rate of migrant worker in a household, transportation in work city, and corporate reputation were not approved by significant testing. 展开更多
关键词 Migrant worker House-purchasing willingness in work construction sites Influential factors Logistic regression analysis Jiangxi Province
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A comprehensive review of lunar lava tube base construction and field research on a potential Earth test site 被引量:1
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作者 Yujie Feng Peng-Zhi Pan +3 位作者 Xuhai Tang Zhaofeng Wang Yuxin Li Altaf Hussain 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第9期1201-1216,共16页
The Moon,as the closest celestial body to the Earth,plays a pivotal role in the progression of deep space exploration,and the establishment of research outposts on its surface represents a crucial step in this mission... The Moon,as the closest celestial body to the Earth,plays a pivotal role in the progression of deep space exploration,and the establishment of research outposts on its surface represents a crucial step in this mission.Lunar lava tubes are special underground caves formed by volcanic eruptions and are considered as ideal natural shelters and scientific laboratories for lunar base construction.This paper begins with an in-depth overview of the geological origins,exploration history,and distribution locations of lunar lava tubes.Subsequently,it delves into the presentation of four distinctive advantages and typical concepts for constructing bases within lava tubes,summarizing the ground-based attempts made thus far in lunar lava tube base construction.Field studies conducted on a lava tube in Hainan revealed rock compositions similar to those found during the Apollo missions and clear lava tube structures,making it a promising analog site.Lastly,the challenges and opportunities encountered in the field of geotechnical engineering regarding the establishment of lunar lava tube bases are discussed,encompassing cave exploration technologies,in-situ testing methods,geomechanical properties under lunar extreme environments,base design and structural stability assessment,excavation and reinforcement techniques,and simulated Earth-based lava tube base. 展开更多
关键词 Lunar lava tube Lunar base construction Extraterrestrial cave exploration Earth analog site
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Groundwater flow analysis in the coastal multi-layer aquifer at the planned construction site of subsurface dam
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《Global Geology》 1998年第1期5-5,共1页
关键词 FLOW Groundwater flow analysis in the coastal multi-layer aquifer at the planned construction site of subsurface dam
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Site Test of Thermal Environment of Rammed Earth Construction in Anji County of China
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作者 马金柱 高璞 《Journal of Landscape Research》 2012年第4期3-9,共7页
The scientific evaluation on heat insulation and preservation capacity of rammed earth construction can provide an effective evidence for its superiority in preserving thermal environment of the construction. By takin... The scientific evaluation on heat insulation and preservation capacity of rammed earth construction can provide an effective evidence for its superiority in preserving thermal environment of the construction. By taking an eco-hotel in Zhejiang Anji County as the research object, 33 test points have been set. The indoor and outdoor air temperature of eco-hotel and the surface temperature of building envelopes had been recorded by using data acquisition instrument, temperature transmitter and other equipments from January 27 to February 2 in 2007. Then, the data of a period had been selected for comparison and analysis and the results had been obtained as follows. In January when the temperature difference between day and night in Anji was not large, without particular thermal insulation measures and equipments, the indoor temperature of eco-hotel fluctuated very little, showing that rammed earth construction was of obvious capacity for heat preservation and insulation, that its heat stability was evident and that it could ensure excellent indoor thermal environment. 展开更多
关键词 Rammed EARTH construction INDOOR THERMAL ENVIRONMENT site test
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Coordinatively unsaturated sites in zeolite matrix: Construction and catalysis 被引量:6
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作者 Weijie Li Lanan Sun +3 位作者 Linjun Xie Xin Deng Naijia Guan Landong Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第9期1255-1281,共27页
Zeolites with ordered porous structure of molecular size are widely employed as commercial adsorbents and catalysts.On the other hand,the zeolite matrix is regarded as an ideal scaffold for hosting coordinatively unsa... Zeolites with ordered porous structure of molecular size are widely employed as commercial adsorbents and catalysts.On the other hand,the zeolite matrix is regarded as an ideal scaffold for hosting coordinatively unsaturated sites.Remarkable achievements have been made dealing with the construction,characterization and catalytic applications of coordinatively unsaturated sites in zeolite matrix.Herein,a literature overview of recent progresses on this important topic is presented from the specific view of coordination chemistry.Different strategies to construction coordinatively unsaturated sites in zeolite matrix,in zeolite framework or extraframework positions,are first introduced and their characteristics are compared.Then,spectroscopic techniques to determine the existing states of cation sites and their transformations in zeolite matrix are discussed.In the last section,the catalytic applications of coordinatively unsaturated sites in zeolite matrix for various important chemical transformations are summarized. 展开更多
关键词 Coordinatively unsaturated sites Zeolite matrix construction Characterization CATALYSIS
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Planning and construction of Xiong’an New Area(city of over 5 million people):Contributions of China’s geologists and urban geology
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作者 Bo Han Zhen Ma +9 位作者 Liang-jun Lin Hong-wei Liu Yi-hang Gao Yu-bo Xia Hai-tao Li Xu Guo Feng Ma Yu-shan Wang Ya-long Zhou Hong-qiang Li 《China Geology》 CAS CSCD 2024年第3期382-408,共27页
China established Xiong’an New Area in Hebei Province in 2017,which is planned to accommodate about 5 million people,aiming to relieve Beijing City of the functions non-essential to its role as China’s capital and t... China established Xiong’an New Area in Hebei Province in 2017,which is planned to accommodate about 5 million people,aiming to relieve Beijing City of the functions non-essential to its role as China’s capital and to expedite the coordinated development of the Beijing-Tianjin-Hebei region.From 2017 to 2021,the China Geological Survey(CGS)took the lead in multi-factor urban geological surveys involving space,resources,environments,and disasters according to the general requirements of“global vision,international standards,distinctive Chinese features,and future-oriented goals”in Xiong’an New Area,identifying the engineering geologic conditions and geologic environmental challenges of this area.The achievements also include a 3D engineering geological structure model for the whole area,along with“one city proper and five clusters”,insights into the ecology and the background endowment of natural resources like land,geothermal resources,groundwater,and wetland of the area before engineering construction,a comprehensive monitoring network of resources and environments in the area,and the“Transparent Xiong’an”geological information platform that is open,shared,dynamically updated,and three-dimensionally visualized.China’s geologists and urban geology have played a significant role in the urban planning and construction of Xiong’an New Area,providing whole-process geological solutions for urban planning,construction,operation and management.The future urban construction of Xiong’an New Area will necessitate the theoretical and technical support of earth system science(ESS)from various aspects,and the purpose is to enhance the resilience of the new type of city and to provide support for the green,low-carbon,and sustainable development of this area. 展开更多
关键词 Low Carbon New City Planning and construction Land Geothermal resources Groundwater Wetland Underground space Geologic disasters site stability Natural resource Ecosystem Geological safety Transparent Xiong’an Resilient city Xiong’an New Area
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Hazardous and Harmful Factors on Construction Sites and Their Prevention
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作者 ZHENG Huanqiang ZHANG Zaiwang RONG Kun 《Journal of Landscape Research》 2019年第1期20-23,28,共5页
In this paper, the status quo of safety production on construction sites and the hazardous and harmful factors in the construction process were analyzed, and corresponding suggestions were proposed to make up for the ... In this paper, the status quo of safety production on construction sites and the hazardous and harmful factors in the construction process were analyzed, and corresponding suggestions were proposed to make up for the shortcomings of the safety production assurance system standards on construction sites. 展开更多
关键词 construction site Safety PRODUCTION MANAGEMENT Identification of hazardous and harmful FACTORS
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An Improved Ant Colony Optimization Algorithm for Construction Site Layout Problems
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作者 Gulben Calis Orhan Yuksel 《Journal of Building Construction and Planning Research》 2015年第4期221-232,共12页
Meta-heuristic algorithms proved to find optimal solutions for combinatorial problems in many domains. Nevertheless, the efficiency of these algorithms highly depends on their parameter settings. In fact, finding appr... Meta-heuristic algorithms proved to find optimal solutions for combinatorial problems in many domains. Nevertheless, the efficiency of these algorithms highly depends on their parameter settings. In fact, finding appropriate settings of the algorithm’s parameters is considered to be a nontrivial task and is usually set manually to values that are known to give reasonable performance. In this paper, Ant Colony Optimization with Parametric Analysis (ACO-PA) is developed to overcome this drawback. The main feature of the ACO-PA is the ability of deciding the appropriate parameter values within the predefined parameter variations. Besides, a new approach which enables the pheromone information value to be proportional to the heuristic information value is introduced. The effectiveness of the proposed algorithm is investigated through the application of the algorithm to the construction site layout problems taken from the state-of-art. Results show that the ACO-PA can reduce transportation cost up to 16.8% compared to the site layouts generated by Genetic Algorithms and basic ACO. Moreover, the effects of parameter settings on the generated solutions are investigated. 展开更多
关键词 ANT COLONY Optimization construction site Layout PARAMETER SETTINGS
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Framework for Improving Construction Health and Safety on Ghanaian Construction Sites
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作者 D. Osei-Asibey J. Ayarkwa +2 位作者 A. Acheampong E. Adinyira P. Amoah 《Journal of Building Construction and Planning Research》 2021年第2期115-137,共23页
The enormity of the problem of construction accidents and hazards in the Ghanaian construction industry (GCI) calls for the need to engage in relevant research to equip stakeholders with the required knowledge to impr... The enormity of the problem of construction accidents and hazards in the Ghanaian construction industry (GCI) calls for the need to engage in relevant research to equip stakeholders with the required knowledge to improve construction health and safety (CHS) and reduce site accidents and hazards. The complexity of the problem of accident causation explains a large number of conceptual models developed to aid the understanding of the dynamics involved in CHS. This paper involved a qualitative study to identify causes of accidents and hazards in the GCI and underlying issues requiring remedying and also a desk study to review Health and Safety related theories and concepts from extant literature to explain and contribute to the improvement of CHS. The paper contributes to the use of theories to advance studies on improving health and safety at construction sites, especially in developing countries like Ghana, where such studies have so far attracted little attention. The framework may enable construction stakeholders to easily identify problem areas on site and apply required improvement measures to create a healthier and safer construction site. The findings may provide useful knowledge to improve CHS and reduce site accidents and hazards, and also provide a multi-theory approach for understanding the dynamics of the complexity of the problems involved in CHS. 展开更多
关键词 FRAMEWORK HEALTH SAFETY Theories Accidents Hazards construction site
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On the Construction of Deepening Anti - corruption Mechanism
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作者 Ding Huanxiang Xuliang 《学术界》 CSSCI 北大核心 2018年第3期260-272,共13页
It needs the foundation of system and the guarantee of organizational system for anti-corruption,but it is more necessary to build and form an effective anti-corruption mechanism,so that the anti-corruption can be rea... It needs the foundation of system and the guarantee of organizational system for anti-corruption,but it is more necessary to build and form an effective anti-corruption mechanism,so that the anti-corruption can be really put into practice. Anti-corruption mechanism refers to a organic operation system of the interaction,interconnection and constraint between the constituent elements( parts) and elements of national anti-corruption,and as a system,anti-corruption mechanism should have the characteristics of system aticness,comprehensiveness,transparency,legalization,public participation,scientific dynam ic,and internationalism. The construction of deepening anti-corruption mechanism is the need for reconstructing the ruling legitimacy of the party and the governm ent. Adhering to the principle of treating both root causes and symptoms is necessary in the construction of anti-corruption m echanism,com bating and punishing corruption is an important part of anti-corruption,and the prevention and control of corruption is the basic project of anti-corruption. Therefore,the construction of prevention and control mechanism in the anti-corruption mechanism has a more far-reaching significance. 展开更多
关键词 anti - CORRUPTION MECHANISM construction CONNOTATION and definition val-ue analysis prevention and control MECHANISM
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Seismic Vulnerability of Building Construction Site
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作者 Ahmed Zahaf Mahmoud Bensaibi 《Journal of Civil Engineering and Architecture》 2014年第1期37-46,共10页
Building construction site plays an important role in the economic aspect of a region. So any disruption due to hazard event like earthquake can cause several direct and indirect damages. Direct damages can lead to th... Building construction site plays an important role in the economic aspect of a region. So any disruption due to hazard event like earthquake can cause several direct and indirect damages. Direct damages can lead to the loss of equipments and qualified persons. Indirect damages can lead to inflation and loss of purchasing power. To deal with that situation, parameters that govern the vulnerability of building construction site have been identified. Using a MCDM (multiple criteria decision making) method, the priority order of these parameters has been set. Then a PVI (partial vulnerability index) and a GVI (global vulnerability index) are proposed. These indexes allow the classification of building construction sites according to their intrinsic vulnerability and seismic vulnerability respectively that is through the use of a given classification. Several Algerian building construction sites belonging to different seismic zones were considered in order to show the applicability of the method. 展开更多
关键词 Seismic vulnerability construction site risk management analytical hierarchy process vulnerability index.
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The Application of Principle of Automatic Control in the site Management of Electric Power Construction Enterprise
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作者 Bowen Wang 《Journal of Electronic Research and Application》 2020年第3期20-23,共4页
It is need to establish site project department during the construction of electric power project.The head office should design and build the main structure,continually improve structure of project department,meantime... It is need to establish site project department during the construction of electric power project.The head office should design and build the main structure,continually improve structure of project department,meantime,positively apply principle of automatic control to improve the site management of electric power construction.In this article,the application strategy of principle of automatic control is analyzed focusing on the site work of electric power construction. 展开更多
关键词 Principle of automatic control Electric power construction construction site management
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Development of a Fuzzy Fire Risk Evaluation Model for Building Construction Sites in Hong Kong
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作者 John F.Y.Yeung Daniel W.M.Chan 《Journal of Construction Research》 2021年第2期27-42,共16页
Earlier research works on fire risk evaluation indicated that an objective,reliable,comprehensive,and practical fire risk evaluation model is essential for mitigating fire occurrence in building construction sites.Nev... Earlier research works on fire risk evaluation indicated that an objective,reliable,comprehensive,and practical fire risk evaluation model is essential for mitigating fire occurrence in building construction sites.Nevertheless,real empirical studies in this research area are quite limited.This journal paper gives an account of the second stage of a research study aiming at developing a fuzzy fire risk evaluation model for building construction sites in Hong Kong.The empirical research findings showed that the overall fire risk level of building construction sites is 3.6427,which can be interpreted as“moderate risk”.Also,the survey respondents perceived that“Restrictions for On-Site Personnel”is the most vital fire risk factor;with“Storage of Flammable Liquids or Dangerous Goods”being the second;and“Attitude of Main Contractor”the third.The proposed fuzzy fire risk evaluation model for building construction sites can be used to assess the overall fire risk level for a building construction site,and to identify improvement areas needed.Although the fuzzy fire risk evaluation model was developed domestically in Hong Kong,the research could be reproduced in other nations to develop similar models for international comparisons.Such an extension would provide a deeper understanding of the fire risk management on building construction sites. 展开更多
关键词 Fire risk evaluation Reliability interval method Fuzzy set Fuzzy synthetic evaluation Building construction sites Hong Kong
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Deep-sea Pollen Record during 3.0-2.0 Ma B.P. from ODP Site 1143 and Its Response to Global Climate Changes 被引量:1
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作者 袁金红 罗运利 +1 位作者 徐兆良 孙湘君 《Marine Science Bulletin》 CAS 2006年第1期1-10,共10页
In order to study vegetation evolution and environmental changes around 2.5 Ma B.P., a total of 146 pollen samples with an average time resolution of 7 000 years were analyzed in the deep-sea record at the depth of 13... In order to study vegetation evolution and environmental changes around 2.5 Ma B.P., a total of 146 pollen samples with an average time resolution of 7 000 years were analyzed in the deep-sea record at the depth of 135 - 95 m (in composition depth) from ODP Site 1143 (9° 22' N, 113° 17' E) in the southern South China Sea. The results show that the pollen influx has a distinct change. During 2.6 - 2.0 Ma B.P., the average value of pollen influx increased evidently compared with that of 3.0 - 2.6 Ma B.P. It shows that the sea level of SCS dropped dramatically around 2.6 Ma B.P., corresponding to the formation of the Northern Hemisphere ice-sheets and the enhancement of the East Asian Monsoon. The pollen influx variations reflect the glacial-interglacial cycles corresponding with the deep-sea oxygen isotope curve and indicate that the sea level of SCS rose and dropped many times after 2.6 Ma B.P. The spectrum analysis results of pollen influx show that there are cycles at 0.1Ma (eccentricity) and 46.9 ka (obliquity) during 3.0 - 2.0 Ma B.P. 展开更多
关键词 pollen influx 3.0 - 2.0 Ma B.P. ODP site 1143 the South China Sea
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基于技术-组织-环境(TOE)与整合型科技接受模式(UTAUT)的智慧工地发展影响因素分析 被引量:2
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作者 薛松 陈静妍 麦锦田 《科技管理研究》 CSSCI 2024年第2期106-116,共11页
智慧工地利用信息技术和可视化平台为建设项目提供精准的工程模型设计,通过智能化管理监督能够实现高效的协同工作和优化生产,但当前智慧工地的普及度和智慧化程度较低,且未实质运行。为此,利用技术-组织-环境(TOE)与整合型科技接受模式... 智慧工地利用信息技术和可视化平台为建设项目提供精准的工程模型设计,通过智能化管理监督能够实现高效的协同工作和优化生产,但当前智慧工地的普及度和智慧化程度较低,且未实质运行。为此,利用技术-组织-环境(TOE)与整合型科技接受模式(UTAUT)组合模型,基于文献数据、政策文本和访谈文本,运用扎根理论的编码方法识别出智慧工地发展的影响因素,同时综合使用DEMATEL-ISM方法对各影响因素之间的层次关系进行研究,探究各因子的影响程度并使其结构层次化。结果表明:核心技术成熟度、现场软硬件设施、产需匹配度和物料设备智能化管理等组织采纳因素是影响智慧工地发展的直接因素;智慧工地的战略目标规划和人员专业化程度是影响智慧工地发展的根本原因,其中人员专业化程度影响程度最大。基于此,政府有关部门应制定合适匹配智慧工地发展的战略目标及战略规划,并通过推广职业认证以提高工作人员的专业素质。 展开更多
关键词 智慧工地 影响因素识别 层次关系 技术-组织-环境(TOE) 整合型科技接受模式(UTAUT)
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基于AHP-GIS的建筑垃圾逆向物流产业园选址研究 被引量:1
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作者 黄莺 张鑫 房姿辰 《市政技术》 2024年第7期196-205,共10页
各类新旧建筑在建造和拆除过程中会产生大量建筑垃圾,从而给建筑垃圾的管理带来巨大压力。为了有效管理建筑垃圾和实现建筑垃圾逆向物流的系统化、规模化、高效化,运用系统动力学理论与方法,构建了建筑垃圾逆向物流SD模型,并对建筑垃圾... 各类新旧建筑在建造和拆除过程中会产生大量建筑垃圾,从而给建筑垃圾的管理带来巨大压力。为了有效管理建筑垃圾和实现建筑垃圾逆向物流的系统化、规模化、高效化,运用系统动力学理论与方法,构建了建筑垃圾逆向物流SD模型,并对建筑垃圾逆向物流综合效益进行了分析。结合产业园选址要求,从经济、环境、社会3个维度,选取10个影响因素,构建了建筑垃圾逆向物流产业园综合效益选址指标体系。通过AHP确定指标权重,并运用ArcGIS软件对指标图层进行叠加,从而实现建筑垃圾逆向物流产业园的选址。以西安市为例,利用ArcGIS软件中欧氏距离分析、重分类分析和栅格计算器等功能模块分析了各指标的适宜性,得到了西安市建筑垃圾逆向物流产业园的最佳选址区域,验证了模型的可行性。该选址方法可为国内其他城市的相关规划提供参考。 展开更多
关键词 建筑垃圾 逆向物流 产业园选址 SD模型 AHP-GIS
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Environmental archaeology on Longshan Culture (4500-4000 aBP) at Yuhuicun Site in Bengbu, Anhui Province 被引量:3
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作者 ZHANG Guangsheng ZHU Cheng +7 位作者 WANG Jihuai ZHU Guangyao MA Chunmei ZHENG Chaogui ZHAO Lanhui LI Zhongxuan LI Lan JIN Aichun 《Journal of Geographical Sciences》 SCIE CSCD 2010年第3期455-468,共14页
Based on the samples collected from the west wall of the ABYT2004 at Yuhuicun Site in Bengbu, Anhui Province, the multi-environmental substitute indexes such as the grain-size, Rb/Sr, zircon crystal morphology and mag... Based on the samples collected from the west wall of the ABYT2004 at Yuhuicun Site in Bengbu, Anhui Province, the multi-environmental substitute indexes such as the grain-size, Rb/Sr, zircon crystal morphology and magnetic susceptibility were analyzed. The age of archaeological strata was determined by AMS^14C dating. According to the results, combined with the information of the ancient human activities and the cultural heritage data obtained from the Longshan cultural archaeological strata, it can be concluded that (1) Before 4500 aBP, the climate was humid and water level was high in the Huaihe River and its tributaries, the drainage basin and its surrounding areas were even flooded, so the site area was submerged and there were no human activities around the site. (2) About 4500 aBP, the climate began to become drier and water level of the Huaihe River and its tributaries began to decline, thus floodplain gradually appeared, Yuhuicun Site and Longshan Culture began to appear. (3) Around 4100 aBP, the climate was humid and rainfall was abundant, which resulted in frequent flood disasters in the whole Huaihe River Basin. (4) After 4100 aBP, the climate gradually transited to be cold and dry, agricultural production was constrained to reduce the food source, Yuhuicun Site was almost abandoned. (5) The environmental information in sedimentary strata and historical records based on ancient books agree with each other. In addition, Yuhuicun Site was related to Dayu Zhishui (Yu the Great in taming the floods) in ancient books. 展开更多
关键词 Yuhuicun site Longshan Culture 4500-4000 aBP environmental change Huaihe River Basin
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Comparative analysis of cast-in-place post-tensioned and steel-concrete composite bridge bent caps 被引量:1
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作者 Nur Yazdani Francisco D.B.Ruiz 《Journal of Modern Transportation》 2017年第3期194-204,共11页
The complexity of the IH-635 Managed Lanes Project, located in Dallas County, Texas, posed several technical and constructive challenges, leading to the adoption of solutions different from the traditional. Two altern... The complexity of the IH-635 Managed Lanes Project, located in Dallas County, Texas, posed several technical and constructive challenges, leading to the adoption of solutions different from the traditional. Two alternative solutions for the pier cap on one of the bridge crossings over IH-35E in the IH-635 project were analyzed in this case study, a cast-in-place post-tensioned concrete cap and an innovative prefabricated steel-concrete com- posite cap. The approach was to use an estimation of direct costs for material and labor and consideration of con- struction time schedules. A supplementary numerical modeling confirmed that both alternatives behave elasti- cally under imposed loads. The direct cost of material and labor for the two alternatives were close. However, the composite alternative required 13 days less construction time, resulting in substantial cost savings from traffic closing in the very busy traffic corridor. Traffic closing costs were substantially higher than the direct costs, especially for the post-tensioned cap. The quantification of the benefits allows more confidence in the utilization of the composites caps, leading to faster completion of bridge projects and substantial economic savings. 展开更多
关键词 Bridge pier cap Bridge bent - Post-tensionedstructure Steel-concrete cap Cost estimation construction schedule Traffic closing cost
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A Comparative Study of Acute Hemodynamic Effects of Multi -site Cardiac Pacing in patients with cardiac function NYHA class ⅠtoⅡ without bundle branch block 被引量:2
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作者 朱参战 崔长琮 +5 位作者 张全发 薛小临 刘维维 刘引会 《South China Journal of Cardiology》 CAS 2001年第2期101-105,共5页
Objective To compare the acute hemodynamic effects of five different pacing modes in patients with cardiac function NYHA class Ⅰ to Ⅱ without bundle branch block (BBB). Methods This study included 12 patients (SSS ... Objective To compare the acute hemodynamic effects of five different pacing modes in patients with cardiac function NYHA class Ⅰ to Ⅱ without bundle branch block (BBB). Methods This study included 12 patients (SSS 7, Ⅲ°AVB 5) undergoing pacemaker implantation. Right ventricular apex (RVA), right ventricular outflow tract (RVOT), right ventricular bifocal (RV-Bi), left ventricular base (LVB) and bi -ventricular (Bi-Ⅴ) pacing at 60 -80 ppm were done in VVI mode prior to implantation of DDD pacemaker. The cardiac index (CI), mean pulmonary artery pressure (mPAP) and pulmonary capillary wedge pressure (PCWP) were measured with Swan - Ganz thermodilution catheter after 5 minutes of each pacing mode. Results (1) Comparing to pacing at RVA (CI: 2. 41± 0. 38 L/min per m2, PCWP: 16. 7 ±3.3 mmHg), the CI increased and the PCWP decreased significantly in pacing at RVOT(CI: 2. 63 ± 0.46, PCWP: 13. 8±2. 3), LVB(CI: 2. 78±0.52, PCWP: 14. 4±3.1), RV-Bi(CI: 2. 83±0.57, PCWP: 12. 8± 2. 5) and Bi -Ⅴ pacing (CI: 2. 94± 0.60, PCWP: 12. 7±2. 5), P < 0. 01, respectively. (2) The CI of RV-Bi and Bi-Ⅴ pacing was higher than that of RVOT and LVB pacing, the PCWP was lower, P < 0. 05, respectively. (3) There was no significant difference between RV - Bi pacing and Bi-Ⅴ pacing in CI and PCWP. Conclusion There is no significant difference between RV - Bi pacing and Bi -V pacing in the acute hemodynamic effects; however,dual - site pacing is much better than single site pacing in that aspect for patients with cardiac function NYHA class Ⅰ to Ⅱ without BBB. Among single site pacing, the RVOT and LVB pacing is better than RVA pacing in cardiac function. 展开更多
关键词 Multi - site cardiac pacingHemodynamics
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Construction of TGP StageⅡWorks
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作者 LIU NingProfessor, Changjiang Water Resources Commission, Wuhan 430010, China WENG Yong-hongProfessor, Design Institute of Changjiang Water Resources Commission, Wuhan 430010, China 《人民长江》 北大核心 2001年第S1期2-4,共3页
In the construction of Three Gorges Project, the total amount of concrete is about 28 Mm\+3 , and the total amount of metal works and reinforcement is approximately 0.72 Mt . The TGP is constructed in 3 stages . The p... In the construction of Three Gorges Project, the total amount of concrete is about 28 Mm\+3 , and the total amount of metal works and reinforcement is approximately 0.72 Mt . The TGP is constructed in 3 stages . The preparation period together with the first stage is 5 years , the second stage and third stage are both 6 years .In the second stage construction of 6 years (1998~2003) , there are 18.46 Mm\+3 of concrete to be placed and 0.192 Mt of metal works and embedded parts for mechanical and electric equipment to be installed . In 1999, a world record of annual concrete placement of 4.585 Mm\+3 was set . In 2000, it is planned to place 5.4 Mm\+3 of concrete and to install 38 000 t of metal works . Construction equipments and layout of construction site , concrete production and its temperature control, metal works, mechanical and electric equipments in the second stage construction are presented. 展开更多
关键词 layout of construction site dual air COOLING concrete equipment INSTALLATION TGP STAGE WORKS
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