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Journal of Mountain Science 2021年第12期18卷 3366-3379页

作者： ZHANG Cheng ZHAO Da-jun ZHANG Shu-lei ZHOU Yu college of construction Engineering Jilin UniversityChangchun 130026China Key Laboratory of Rock Mechanics and Geohazards of Zhejiang Province Shaoxing UniversityShaoxing 312000China Yellow River Survey Planning and Design Institute Co.Ltd.Zhengzhou 450003China

Ultrasonic vibration technology has great potential to weaken hard *** the effect of ultrasonic vibration loading parameters is essential to accelerate the application of this technology in practical rock *** the present work,three-factor mixed-level orthogonal ultrasonic vibration rock breaking tests were conducted to investigate the influence of the main loading parameters,including confining pressure,vibration frequency,and static force,on the damage of granite *** individual and combined influences were analyzed according to the porosity increase and P-wave decrease of granite specimens using the variance analysis *** results show that the combined effect of the static force and vibration frequency mainly promotes fatigue damage of specimens,that the confining pressure determines the damage behaviour and failure mode of specimens under ultrasonic vibration,and that the confining pressure and vibration frequency are the main factors that cause the fracture concentration in the upper part of specimens,an effect mechanistically driven by the obvious load energy *** research results provide theoretical guidance for the application of ultrasonic vibration technology.

关键词： Ultrasonic vibration Granite Damage evolution Confining pressure Vibration frequency Static force Combined effect

Analysis of moisture and total sugar content of Huizao based on surface images

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International Journal of Agricultural and Biological Engineering 2018年第4期11卷 238-243页

作者： Junxiong Zhang Qingqing Ma Fen He Feng Qu Wei Li college of Engineering China Agricultural UniversityBeijing 100083China Chinese Academy of Agricultural Engineering planning and design Beijing 100125China Key Laboratory of Farm Building in Structure and construction Ministry of Agriculture and Rural AffairsBeijing 100125China

Moisture and total sugar content are two important internal qualities of *** order to explore their correlation with external qualities,a novel method of moisture and total sugar content analysis was proposed based on surface ***,five geometric features and seven texture features of Huizao were obtained to be the external quality indexes by digital image processing ***,the wrinkle degree as an important index was extracted by marked watershed segmentation *** to the external quality the Huizao samples were grouped,and the moisture and total sugar content were determined through physical and chemical ***,the moisture and total sugar content and twelve external indexes were all processed by step discriminatory ***,the regression models of moisture content with short diameter,contrast,and wrinkle degree and total sugar with wrinkle degree were *** coefficients of the model were 0.9992 and 0.9978 respectively,and all the significance was less than 0.01,which show that the regression equation and regression coefficient effect are highly *** results indicate that the moisture and total sugar content of Huizao are greatly correlated with the wrinkle *** moisture and total sugar content are the highest when the wrinkle degree is at 2 to 3 grade,and they decrease gradually with the wrinkle degree *** content shows positive correlation with the size of *** results of model analysis agree well with the experimental results,which can provide valuable reference for improving Huizao grade diversity.

关键词： Huizao step discriminatory analysis moisture content total sugar

RISK MODEL FOR ENERGY PERFORMANCE CONTRACTING IN CORRECTIONAL FACILITIES

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Journal of Green Building 2019年第2期14卷 61-82页

作者： George H.Berghorn Matt Syal construction Management Michigan State University School of PlanningDesignand Construction construction Management Michigan State University School of PlanningDesign

Energy performance contracting provides guaranteed minimum energy savings to building owners,enabling them to finance project costs using utility savings over the duration of the *** has been an attractive project delivery method for organizations with reduced budgets for capital projects,particularly among correctional facilities which frequently have lengthy periods of deferred maintenance and ongoing building operations and maintenance *** research builds on a previously developed project factors risk framework for energy service companies undertaking building *** paper proposes a risk analysis and evaluation model that includes quantitative,expert-based,and probabilistically derived infor*** cost was used to evaluate risks over lengthy project life cycles and a new metric was developed for use in the model-expected life cycle *** results reveal that the most critical risk factors relate to the reduced availability of“low-hanging fruit”energy conservation measures,work scopes based on traditional design-bid-build procurement,unavailable or inaccurate facility information,facility age and current code requirements,and conducting the investment grade audit too *** life cycle cost-based risk model employed in this paper is proposed as an advancement over traditional risk management methods,and it is expected to be applicable,with modification,across other municipal and state government subdomains,especially high security projects.

关键词： energy performance contracting(EPC) energy efficient building practices building retrofits project performance risks risk modeling scenario failure mode and effect analysis(SFMEA)

Regulations and patterns of soil moisture dynamics and their controlling factors in hilly regions of lower reaches of Yangtze River basin,China

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Journal of Central South University 2015年第12期22卷 4764-4777页

作者：余蔚青王玉杰胡海波王云琦张会兰王彬刘勇 School of Soil and Water Conservation Beijing Forestry University Key Laboratory of Soil and Water Conservation and Desertification Combating of Ministry of Education (Beijing Forestry University) Integrate planning and design Institute China Aviation Planning and Design Institute (Group) Co.Ltd. college of Forest Resources & Environment Nanjing Forestry University

Time-domain reflectometry was used to make continuous measurements of soil moisture to 18 sample points with depth of 2 m for 36 months in a typical artificial secondary oak forest located in a hilly area on Zijin Mountain in the suburbs of Nanjing,*** data were then used to examine the patterns of soil moisture variations on temporal and spatial scales and predict the relationships between soil moisture and major factors of both meteorology and *** in the topsoil was active,and the upper 30 cm of soil supplied about 43% of the water content variation during the whole *** difference of water content changes among layers could be due to the distribution conditions of some soil physical *** initial soil moisture was in the range from 10% to 40%,the impact of a single storm event on soil moisture was extremely significant,especially on sunny *** climate and slope condition were related to soil moisture change,and the impact of slope gradient on soil moisture was higher that on shady ***,root uptake was another important path of soil water consumption.

关键词： soil moisture precipitation slope gradient root distribution soil water consumption

Evaluation of social network conservation in historical areas of mountainous towns in Chongqing, China

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Journal of Mountain Science 2020年第7期17卷 1763-1775页

作者： SHI Ya-ling HUANG Yong HU Dong-yang WAN Dan Faculty of Architecture and Urban planning Chongqing UniversityChongqing400030China The Bartlett School of construction and Project Management University College London1-19 Torrington PlaceLondonWC1E 7HBUK Key Laboratory of New Technology for construction of Cities in Mountain Area Chongqing UniversityChongqing400030China Chongqing University planning&design Institute Co. LtdChongqing400044China

Over recent decades,historical areas conservation has become an important strategy to improve urban competitiveness in the global *** shown in existing studies that the conservation of historical areas mainly focused on the physical environment,there is still room for the non-physical study,and researches on the social network conservation in mountainous historical areas are particularly ***,this paper aims to establish an evaluation system which is helpful for the social network conservation of historical *** evaluation system is based on social network analysis and the information of social relationships gathered in field surveys using a specifically designed questionnaire method in four mountainous towns in Chongqing,*** it was analyzed from three perspectives,i.e.,by the basic statistical properties,condensate subgroup,and *** five analysis indicators were conceived,including density,lambda set,k-core,degree centrality,and betweenness *** analysis results demonstrate that the social networks of the four towns show different indicators,which are respectively relevant to completeness degree,edgerelatedness level,local stability,structural balance,and concentrated trend of social *** from SNA modeling indicate that neighborhood residents of historical areas who have more stable and healthier social relationships are relatively not easily be *** results also illustrate that the social networks structure is influenced by the terrain,form,and function of historical areas,and the change of historical areas is caused by"individual-family-society".Finally,the strategies guiding the social network conservation are put forward from two *** findings suggest that the conservation and management of social network and aborigines in historical areas should be emphasized to increase the collective benefits and vitality.

关键词： Historical areas Social network analysis Physical environment Evaluation Conservation Mountainous towns

Calculation of Mass Concrete Temperature and Creep Stress under the Influence of Local Air Heat Transfer

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2977-3000页

作者： Heng Zhang Chao Su Xiaohu Chen Zhizhong Song Weijie Zhan Academy of Science and Technology Changjiang Institute of Survey Planning Design and ResearchWuhan430010China college of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China Chief Engineer Office Wujiang Company of Goupitan Power Construction CooperationYuqing564408China

Temperature-induced cracking during the construction of mass concrete is a significant *** simulations of concrete temperature have primarily assumed that the concrete is placed in an open *** problem of heat transfer between the air and concrete has been simplified to the concrete’s heat dissipation ***,in the case of tubular concrete structures,where air inlet and outlet are relatively limited,the internal air temperature does not dissipate promptly to the external environment as it *** accurately simulate the temperature and creep stress in tubular concrete structures with enclosed air spaces during construction,we establish an air–concrete coupled heat transfer model according to the principles of conjugate heat transfer,and the accuracy of the model is verified through ***,we conduct a case study to analyze the impact of airflow within the ship lock corridor on concrete temperature and creep *** results demonstrate that enhancing airflow within the corridor can significantly reduce the maximum concrete *** with cases in which airflow within the corridor is neglected,the maximum concrete temperature and maximum tensile stress can be reduced by 12.5℃ and 0.7 MPa,respectively,under a wind speed of 4 m/*** results of the traditional calculation method are relatively close to those obtained at a wind speed of 1 m/***,the temperature reduction process in the traditional method is faster,and the method yields greater tensile stress values for the corridor location.

关键词： Conjugate heat transfer temperature field mass concrete creep stress

Grain size characteristics of surface sediment and its response to the dynamic sedimentary environment in Qiantang Estuary, China

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International Journal of Sediment Research 2022年第4期37卷 457-468页

作者： Shanshan Wang Cunhong Pan Dongfeng Xie Mingwei Xu Yuhan Yan Xinwen Li Zhejiang Institute of Hydraulics & Estuary (Zhejiang Institute of Marine planning and design) college of Harbour Coastal and Offshore EngineeringHohai University

The composition and grain size characteristics of sediment in estuarine and coastal environments provide important information on the material source, hydrodynamic environment, environmental events,etc. However, few studies have focused on the sediment characteristics of the entire Qiantang Estuary,particularly, on the correlation between hydrodynamics and sediment properties. Through systematic sampling of the surface sediment in a large area of the Qiantang Estuary, the spatial distribution characteristics of the surface sediment of the Qiantang Estuary, such as the grain size composition and particle size parameters, in different sections of the estuary area are analyzed. By comparing the particle size data of different estuaries, the similarities and differences of the particle size parameters of the Qiantang Estuary and other estuaries are compared and analyzed. According to the differences in the sediment composition, the distribution status of the particle size frequency curves and the morphological characteristics of the probability curves in the entire study area, the Qiantang Estuary is divided into 7 dynamic depositional areas: Fuchunjiang Hydropower Station-Fuyang, Fuyang-Qibao, Qibao-Cao’e River, Cao’e River-Zhapu, North Shore of Hangzhou Bay, middle part of Hangzhou Bay, and South Shore of Hangzhou Bay, which are different from the previous estuary segmentation system. The study area is divided into 13 dynamic depositional sub-regions using the Pejrup M triangle diagram. Combining the calculation results of the mathematical model and the Pejrup M triangle diagram, the relation between the dynamic deposition environment and the bottom shear stress is discussed. It is found that the spatial distribution of the bottom shear stress in the study area is in good agreement with the zoning of the dynamic sedimentary environment.

关键词： Qiantang Estuary Surface sediment Grain size parameter characteristics Dynamic sedimentary environment

Dynamic transfer and driving mechanisms of the coupling and coordination of agricultural resilience and rural land use efficiency in China

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Journal of Geographical Sciences 2024年第8期34卷 1589-1614页

作者： CHEN Xiaohong AN Yongle PAN Wei WANG Ying CHEN Lintao GU Yue LIU Haihan YANG Fan college of Geography Science Harbin Normal UniversityHarbin 150025China Harbin Urban and Rural planning&design Institute Harbin 150010China

The joint study of agriculture and rural areas is of great significance for safeguarding agricultural development,revitalizing rural areas,and enhancing farmers'*** paper aims to assess the spatiotemporal evolution characteristics of the coupling and coordination degree of agricultural resilience and rural land use efficiency and their dynamic transfer law and driving mechanisms,based on panel data of 31 provinces(municipalities and autonomous regions)in China from 2010 to *** results showed:(1)Good coupling and coordination of agricultural resilience and rural land use efficiency,with reduced temporal differentiation degrees between regions;(2)Significant spatial autocorrelation between the overall coupling and coordination degrees of agricultural resilience and rural land use efficiency,forming cold spot and hot spot spatial patterns in the western and eastern parts,respectively,with a central transition area;(3)A spillover effect of the dynamic transfer process,with a manifested specific law as"club convergence","Matthew effect",and progressive development characteristics;(4)The key roles of the natural,social,economic,and policy indicators in the coupling and coordination development process of agricultural resilience and rural land use ***,the selected indicators showed substantial spatial differences in their influences on the coupling and coordination process between provinces.

关键词： agricultural resilience rural land use efficiency coupling and coordination analysis dynamic transfer drivingmechanisms

Hazard and vulnerability evaluation of water distribution system in cases of contamination intrusion accidents

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Frontiers of Environmental Science & Engineering 2012年第6期6卷 839-848页

作者： Kunlun XIN Tao TAO Yong WANG Suiqing LIU college of Environmental Science and Engineering Tongji UniversityShanghai 200092China Zhejiang Urban&Rural planning design Institute Hangzhou 300072China

In this paper, it proposed an index system for hazard and vulnerability evaluations of water distribution networks, based on the simulation of contamination events caused by pollutant injections at different junctions. It attempted to answer the following two questions in the case of contamination events： 1） Which are the most hazardous junctions？ 2） Which are the most vulnerable junctions？ With EPANET toolkit, it simulated the propagation of the contaminant, and calculated the peak concentration of the contaminant and mass delivered at different nodes. According to types of consumers, different weights were assigned to the consumer nodes for assessing the influence of the contaminant on the consumers. Using the method proposed herein, both the hazard index and vulnerability index were calculated for each node in the pipe network. The presented method was therefore applied to the water network of the city of Zhenjiang, which contains two water plants, two booster pump stations with storage tanks. In conclusion, the response time, the relationships between the peak concentration of contami- nant and the total absorption are the most important factors in hazard and vulnerability evaluation of the water distribution network.

关键词： water distribution network hazard vulner-ability contaminant accident

Spatiotemporal Differences and Classification Regulation of Urbanization Impact on Agricultural Development in Shrinking Areas:A Case Study of 15 Shrinking Cities in Three Provinces of Northeast China

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Chinese Geographical Science 2023年第6期33卷 1053-1067页

作者： CHEN Xiaohong LIU Haihan AN Yongle DAI Yue PAN Wei WANG Ying TANG We college of Geography Science Harbin Normal UniversityHarbin150025China Harbin Urban and Rural planning&design Institute Harbin150010China

Studying the impact of urbanization on agricultural development in shrinking areas is important for maintaining food security and promoted agricultural development in *** on the measurement results of the shrinking cities in the three provinces of Northeast China,this paper selects 15 shrinking cities as the research object,and constructs a multi-dimensional index system to explore the impact of the urbanization level of the shrinking areas on the agricultural development in the region since 2007–2019,analyzes the influencing factors and their differences by using the geographically-weighted regression model and Geodetector,and proposes a targeted regulation *** results show that:1)overall,there is a negative correlation between the urbanization level and the agricultural development level in the contracted areas of the three northeastern *** urbanization level in these areas has a certain negative impact on the overall level of agricultural development;2)regarding the time dimension,the impact of urbanization level on the agricultural development level in the contracted areas of the three northeastern provinces gradually increases over time;3)regarding the spatial pattern,the overall impact of shrinking urbanization levels in the three provinces of Northeast China on the agricultural development shows a significant distribution pattern of high in the east and low in the west;4)the total population and natural population growth rate at the end of the year were the main factors influencing a certain level of urbanization on agricultural development in the shrinking cities while population density and the urban fixed asset investment rate were the secondary factors;and 5)the main reasons why the level of agricultural development in different cities was affected by the level of urbanization were ***,they can be categorized into areas of population loss and spatial construction,which can be further divided into area of population

关键词： urbanization agricultural development classification and regulation shrinking cities three provinces of Northeast China