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Spatio-temporal evolution and topographic gradient effect of land use and ecosystem service value in the Lhasa River Basin
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作者 ZHOU Jianwei FENG Bin +8 位作者 WU Hua XU Tong CHEN Linna ZHAO Xinyong GUO Qiyun LI Jiatong ZHANG Chenguang ZHU Kangcheng KONG Yuzhong 《Journal of Mountain Science》 SCIE CSCD 2024年第6期2059-2074,共16页
The Lhasa River Basin forms an essential human settlement area in the southern part of the Qinghai-Tibet Plateau.This study employed ecosystem service value(ESV)evaluation model,terrain gradient grading,and Geodetecto... The Lhasa River Basin forms an essential human settlement area in the southern part of the Qinghai-Tibet Plateau.This study employed ecosystem service value(ESV)evaluation model,terrain gradient grading,and Geodetector to analyze land use and ESV in the Lhasa River Basin from 1985 to 2020.The findings reveal that:(1)From 1985 to 2020,grassland was the dominant land use.There was a trend of grassland reduction and the expansion of other land types.(2)ESV has increased over the research period(with a total increase of 0.84%),with higher values in the southeast and lower values in the northwest.Grassland contributed the most to ESV,and climate regulation and hydrological regulation were the ecosystem services that contribute the most to ESV.(3)Natural factors like NDVI and altitude,as well as economic factors like population density and distance from roads,influenced the spatial differentiation of ESV,the explanatory power of NDVI reached up to 0.47.The interaction between factors had a greater impact than individual factors.These research results can provide theoretical support for national spatial planning and ecological environment protection in the Lhasa River Basin and other similar areas. 展开更多
关键词 Ecosystem services value Land use Terrain gradient effect Lhasa River Basin Driving factors
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Spatiotemporal evolution of ecosystem service value and topographic gradient effect in the Da-Xiao Liangshan Mountains in Sichuan Province,China 被引量:2
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作者 JIN Tao CHEN Yang +2 位作者 SHU Bo GAO Min QIU Jian 《Journal of Mountain Science》 SCIE CSCD 2023年第8期2344-2357,共14页
The Da-Xiao Liangshan mountains are critical ecological function areas and essential ecological barriers in the upper reaches of the Yangtze River in China.This study selected a total of six periods of land use land c... The Da-Xiao Liangshan mountains are critical ecological function areas and essential ecological barriers in the upper reaches of the Yangtze River in China.This study selected a total of six periods of land use land cover(LULC)data from 1995 to 2020,to estimate the ecosystem service value(ESV)and analyzed its spatiotemporal evolution and topographic gradient divergence.The results showed that:(1)The ESV increased by 1.1 billion yuan,with an increase rate of 1.47%from 1995 to 2020.Two time periods,2005–2010 and 2015–2020,showed more significant increases than other periods.(2)The elevation and slope of mountainous areas determine the type of land use and further influence the spatial pattern of ESV.(3)Although woodland and grassland are the main land use types of the study area(more than 90%),the hydrological regulation function of the water area partially compensated for the impact of the encroachment of the built-up area on the ESV of grassland.(4)The spatial distribution of ESVs showed an inverted V-shaped characteristic as the topographic gradient increased,with the dominant position being the 5th topographic gradient zone.Finally,this study provided relevant recommendations for ecosystem protection and optimization.The findings of this study clarified the influence of topographical factors on the spatial differentiation of ESV and provided novel insights into ecosystem protection. 展开更多
关键词 Ecosystem service value(ESV) Dynamic evolution Terrain gradient effect Spatial pattern Liangshan Yi region
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A novel model for cost performance evaluation of pulverized coal injected into blast furnace based on effective calorific value 被引量:4
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作者 徐润生 张建良 +3 位作者 左海滨 李克江 宋腾飞 邵久刚 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第10期3990-3998,共9页
The combustion process of pulverized coal injected into blast furnace involves a lot of physical and chemical reactions. Based on the combustion behaviors of pulverized coal, the conception of coal effective calorific... The combustion process of pulverized coal injected into blast furnace involves a lot of physical and chemical reactions. Based on the combustion behaviors of pulverized coal, the conception of coal effective calorific value representing the actual thermal energy provided for blast furnace was proposed. A cost performance evaluation model of coal injection was built up for the optimal selection of various kinds of coal based on effective calorific value. The model contains two indicators: coal effective calorific value which has eight sub-indicators and coal injection cost which includes four sub-indicators. In addition, the calculation principle and application of cost performance evaluation model in a Chinese large-scale iron and steel company were comprehensively introduced. The evaluation results finally confirm that this novel model is of great significance to the optimal selection of blast furnace pulverized coal. 展开更多
关键词 blast furnace pulverized coal injection effective calorific value cost performance evaluation model
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THE ESTIMATE OF THE EFFECTIVE FUEL COMBUSTION VALUE OF FOREST COMMUNITY IN THE DAXINGAN MOUNTAIN
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作者 刘自强 王希田 +1 位作者 陈大我 张明石 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1994年第1期59-63,共5页
Under the condition of absolute dry, more than thirty forest fuel pararneters,ash content. extract and burning point were measured. By the method of regression step by step. we found an experience formula which can es... Under the condition of absolute dry, more than thirty forest fuel pararneters,ash content. extract and burning point were measured. By the method of regression step by step. we found an experience formula which can estimate effective fuel high combusti on value of forest community from the Daxingan Mountain,and then,By means of modifying moisture content. we gave an approximate formula about actual heat releasing of forest fuels in the forest fire behavior. 展开更多
关键词 Forest community effective fuel Combustion value
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Mechanism for Increasing Effective Inputs in Urban Agriculture through Industrial Value Chain
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作者 YUN Xiao-lan Tianjin Agricultural University,Tianjin 300384,China 《Asian Agricultural Research》 2012年第3期3-6,共4页
This paper firstly introduces the value chain management thought,current situations of utilization,and connotation of mechanism for increasing effective inputs in urban agriculture through industrial value chain.On th... This paper firstly introduces the value chain management thought,current situations of utilization,and connotation of mechanism for increasing effective inputs in urban agriculture through industrial value chain.On the basis of basic idea of value chain management,this paper is to explore the mechanism for increasing effective inputs in urban agriculture through the value chain of urban agriculture linking with other industries. 展开更多
关键词 URBAN AGRICULTURE Industrial value CHAIN effective
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Temperature Stimulation of Effective Value of Density of the Current of Semiconductor Solar Cells
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作者 Aliev Rayimjon Ikromov Rustamjon Gulomjonovich Alinazarova Mahfuza Alisherovna 《Energy and Power Engineering》 2019年第2期92-97,共6页
Influence of temperature on effective value of a current density of a semiconductor solar cell is investigated. New equations for explanation of dependence of photovoltaic characteristics of solar cell from temperatur... Influence of temperature on effective value of a current density of a semiconductor solar cell is investigated. New equations for explanation of dependence of photovoltaic characteristics of solar cell from temperature are received. 展开更多
关键词 SEMICONDUCTOR Solar Сell effective value of a CURRENT TEMPERATURE DEPENDENCE of PHOTOVOLTAIC Parameters PHOTOVOLTAIC Characteristics
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Exploring the Educational Value of Mathematical Beauty and Effective Ways of Discovering Mathematical Beauty
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作者 Cunrong Wang 《Journal of Contemporary Educational Research》 2021年第10期82-87,共6页
The precision of mathematical reasoning,the abstractness of mathematical language,the profundity of mathematical thought and method,as well as the excessive formalization of mathematics teaching have formed an impassa... The precision of mathematical reasoning,the abstractness of mathematical language,the profundity of mathematical thought and method,as well as the excessive formalization of mathematics teaching have formed an impassable gap,hindering students in approaching mathematics.This has concealed the beauty of mathematics and the light of mathematical culture.However,if students are able to cross this gap,they would find that mathematics is a vast world full of vitality,imagination,wisdom,poetry,and beauty.The pursuit of mathematical beauty is one of the motivations for scientists to research this field.Experiencing mathematical beauty is of great significance to students'learning and growth.In teaching,the value of mathematical beauty is explored,such as stimulating emotions,opening up to the truth,and cultivating goodness.Several effective ways are suggested in this article to guide students to discover the mathematical beauty in life while finding it in problem-solving methods and exploring it in knowledge systems. 展开更多
关键词 Mathematical beauty Educational value effective way
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A Methodology of Metamaterial Effective Permittivity and Permeability Value Measurement
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作者 A. S. Kukharenko R. V. Shaymardanov A. A. Yelizarov 《材料科学与工程(中英文A版)》 2017年第4期206-215,共10页
关键词 等效介电常数 测量方法 磁导率 材料 电介质结构 有效介电常数 矢量网络分析仪 测量工具
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Effect of Cu and Ni on Growth, Mineral Uptake,Photosynthesis and Enzyme Activities of Chlorella vulgaris at Different pH Values 被引量:3
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作者 P.K.RAI NirupamaMALLICK 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1994年第1期56-67,共12页
A pH dependent reduction in growth, Pigment, ATP content, O,' evolution, carbonfixation, Photosynthetic electron transport system, nutrient uptake (NO,' and NH4+),nitrate reductase, and ATPase activities and i... A pH dependent reduction in growth, Pigment, ATP content, O,' evolution, carbonfixation, Photosynthetic electron transport system, nutrient uptake (NO,' and NH4+),nitrate reductase, and ATPase activities and increase in K+ emux of Chlorella vulgaris wasnoticed following supplementation of Cu and Ni to the culture medium. PS II was foundto be more sensitive to both pH and metals than PS I. Though, nitrate reductase (NR) wasmore sensitive to both PH and metals, the ATPase was however, more sensitive t0 metalsbut less sensitive to acidic pH. Acid PH was found to dst the nutrient (NO,' and NH4+)uptake and nitrate reductase in a non-competitive manner. The inhibition Pnduced by thetest metals alone was of noncompetitive type for NO3' uptake, nitrate reductase andATPase and competitive for NH'+ uptake. Acidity not only inhibited the metabolicvariables directly but also through facilitated uptake of metals and increased membranepermeability. A very low sensitivity of ATPase to acidic pH seems to be resgnsible forthe survival of algae in acid environment. 展开更多
关键词 Mineral Uptake Photosynthesis and Enzyme Activities of Chlorella vulgaris at Different pH values effect of Cu and Ni on Growth pH CU NI
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Effect of corporate social responsibility on creation of added value 被引量:2
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作者 FANG Xiao-zhi YANG Chun-qing YU Jun 《Ecological Economy》 2016年第4期376-383,共8页
In the process of financial management and operation, a firm should not only aim to maximize its shareholders' benefits, but also consider the interests of all stakeholders. Bearing social responsibility to each s... In the process of financial management and operation, a firm should not only aim to maximize its shareholders' benefits, but also consider the interests of all stakeholders. Bearing social responsibility to each stakeholder to a certain extent and pursuing harmonious social development are fully consistent with the concept of China's building a harmonious socialist society. Furthermore, added value also reflects the idea of social responsibility Based on the relational contract theory, the paper divides stakeholders into staff and shareholders under relational contracts, creditors, suppliers and consumers under transactional contracts and governments and communities under special contracts. The paper details the effect mechanism of a firm's bearing social responsibilities to each stakeholder on the creation of added value respectively, and considers that corporate social responsibilities should be included in the system for creating added value to theoretically support firm managers to fulfill social responsibilities. 展开更多
关键词 corporate social responsibilities added value effect mechanism
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Capacitance Characterization of the Effect of pH Value on the Self-assembled Monolayers of Octadecanethiol
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作者 KeQiangDING QingFeiWANG +1 位作者 RuTingTONG HuiBoSHAO 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第4期411-412,共2页
In this paper, the membrane capacitance (Cm), which was obtained from the electro- chemical impedance spectroscopy (EIS) method, was used to characterize the effect of pH value on the self-assembled monolayers (SAMs) ... In this paper, the membrane capacitance (Cm), which was obtained from the electro- chemical impedance spectroscopy (EIS) method, was used to characterize the effect of pH value on the self-assembled monolayers (SAMs) of octadecanethiol(18SH) for the first time. The results not only strongly proved that inorganic ions could penetrate the SAMs of 18SH, but also ascertained that SAMs of 18SH were not an absolute of free of ion-penetration. Verifying the existence of pin-holes in the octadecanethiol SAMs was the main contribution of this paper, which coincided with the former conjecture very well. 展开更多
关键词 Octadecanethiol SAMS effect pH value capacitance characterization.
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Research on the Value and Strategy of Integrating Music Education and National Music Culture
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作者 Liangyihui Chen 《Journal of Contemporary Educational Research》 2023年第9期14-19,共6页
China’s traditional national music is an art form formed by the working people and art pioneers to express their emotions during thousands of years of productive labor.National music not only contains emotional stori... China’s traditional national music is an art form formed by the working people and art pioneers to express their emotions during thousands of years of productive labor.National music not only contains emotional stories that are capable of evoking praises and tears,but also has a profound understanding of the lives of sages.In summary,integrating college music education with national music culture can allow students to deeply discover music,thereby stimulating students’enthusiasm for learning music,improving students’learning quality,mastering the core parts of music learning,and helping students to go a long way in music.This article mainly focuses on the characteristics and educational value of national music culture,and its effective integration with music education in colleges and universities.This article can help relevant workers in college music education and promote the sustainable development of music education in colleges and universities in China. 展开更多
关键词 Music education in colleges and universities National music culture effective integration Teaching value
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Fatigue Damage Assessment by Considering Mean Value Effect in Frequency Domain
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作者 丁红岩 朱奇 张浦阳 《Transactions of Tianjin University》 EI CAS 2015年第2期161-166,共6页
Fatigue damage assessment is carried out considering mean value effect by applying four criteria of failure. Three frequency domain methods, i.e., level crossing counting(LCC), range counting(RC) and a new proposed me... Fatigue damage assessment is carried out considering mean value effect by applying four criteria of failure. Three frequency domain methods, i.e., level crossing counting(LCC), range counting(RC) and a new proposed method, are applied. The core of frequency domain method is the construction of probability density function for the mean stress and stress range of the stress process. The applicability of these frequency domain methods are inspected by comparing with time domain method. Numerical simulations verify the applicability of LCC and the proposed method, while RC gives poor estimations. 展开更多
关键词 FATIGUE mean value effect S-N CURVE frequency DOMAIN rainflow COUNTING
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Contemporary Values of Confucianism and the Effectiveness of Internal Control in Corporate Management:Compatibility between Management Culture and Systems in Chinese Enterprises
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作者 ZHANG Xuan SHU Yingqi 《Frontiers of Business Research in China》 2024年第1期62-81,共20页
Based on data from China’s A-share listed companies from 2008 to 2017,this paper examines the influence of the contemporary values of Confucianism,namely benevolence,righteousness,propriety,wisdom,and fidelity on the... Based on data from China’s A-share listed companies from 2008 to 2017,this paper examines the influence of the contemporary values of Confucianism,namely benevolence,righteousness,propriety,wisdom,and fidelity on the effectiveness of internal control.It indicates a significant positive correlation between the contemporary values of Confucianism and the effectiveness of internal control.Furthermore,this positive influence is noticeable in family-owned businesses but is unobserved in foreign-invested enterprises in China.In addition,the contemporary values of Confucianism enhance internal control quality through two pathways:promotion incentives and corporate reputation.In regions with lower degrees of openness,lower levels of rule of law and slower marketization,or in companies facing operational crises,the contemporary values of Confucianism have a more pronounced effect on enhancing the effectiveness of internal control.The contemporary values of Confucianism have strengthened the ability of internal control to decrease agency costs and mitigate the negative influence of internal control on risk-taking. 展开更多
关键词 CONFUCIANISM contemporary values effectiveness of internal control quality of internal control corporate governance corporate culture
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A Medicinal and Edible Plant Crocus sativus L.and Its Therapeutic Effects on Cardiovascular and Cerebrovascular Diseases
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作者 Rena Abulaiti Ping YAN 《Medicinal Plant》 2024年第4期29-30,共2页
This paper introduces the biological characteristics,medicinal value,chemical component,and pharmacological effects of Crocus sativus L.,and explores its therapeutic effects on cardiovascular and cerebrovascular disea... This paper introduces the biological characteristics,medicinal value,chemical component,and pharmacological effects of Crocus sativus L.,and explores its therapeutic effects on cardiovascular and cerebrovascular diseases such as angina pectoris and coronary heart disease. 展开更多
关键词 Crocus sativus L. Cardiovascular and cerebrovascular diseases Medicinal value Therapeutic effect
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Calendar Effects in AAPL Value-at-Risk
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作者 Hong-Kun Zhang Zijing Zhang 《Journal of Mathematics and System Science》 2016年第6期215-233,共19页
This study investigates calendar anomalies: day-of-the-week effect and seasonal effect in the Value-at-Risk (VaR) analysis of stock returns for AAPL during the period of 1995 through 2015. The statistical propertie... This study investigates calendar anomalies: day-of-the-week effect and seasonal effect in the Value-at-Risk (VaR) analysis of stock returns for AAPL during the period of 1995 through 2015. The statistical properties are examined and a comprehensive set of diagnostic checks are made on the two decades of AAPL daily stock returns. Combing the Extreme Value Approach together with a statistical analysis, it is learnt that the lowest VaR occurs on Fridays and Mondays typically. Moreover, high Q4 and Q3 VaR are observed during the test period. These results are valuable for anyone who needs evaluation and forecasts of the risk situation in AAPL. Moreover, this methodology, which is applicable to any other stocks or portfolios, is more realistic and comprehensive than the standard normal distribution based VaR model that is commonly used. 展开更多
关键词 Risk Measures value-AT-RISK Extreme value theory Generalized Pareto Distribution Day-of-the-week effect Seasonaleffect
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Modelling seedling development using thermal effectiveness and photosynthetically active radiation 被引量:5
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作者 ZHOU Tian-mei WU Zhen +4 位作者 WANG Ya-chen SU Xiao-jun QIN Chao-xuan HUO He-qiang JIANG Fang-ling 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第11期2521-2533,共13页
Seedling quality is a prerequisite for successful field performance and therefore influences crop yields. Temperature and illumination are two major factors affecting seedling quality during nursery propagation. Subop... Seedling quality is a prerequisite for successful field performance and therefore influences crop yields. Temperature and illumination are two major factors affecting seedling quality during nursery propagation. Suboptimal temperature or light of nurseries generally result in leggy or weak seedlings and great economic loss. However, production of healthy seedlings is challenging due to the lack of knowledge in systemic management of nursery environments. In this study, we have established simulation models to predict how temperature and illumination coordinately influence the growth of tomato and cabbage seedlings. Specifically, correlation between seedling quality characteristics(root-shoot ratio, G value(growth function: defined as ratio of whole plant dry weight to days of seedling), healthy indexes) and TEP(thermal effectiveness and photosynthetically active radiation) were explored to establish the models, which were validated with independent test data. Our results suggested that the curve of healthy index 1(HI1) and TEP fitted well with high coefficient of determination(R2) in both species, indicating that the model is highly reliable. The HI1 simulation models for tomato and cabbage are HI1=0.0009e0.0308TEP-0.0015 and HI1= 0.0003e0.0671TEP-0.0003, respectively, which can be used for predicting vigors of tomato and cabbage seedlings grown under different temperature and light conditions. 展开更多
关键词 TOMATO CABBAGE simulation model thermal effectiveNESS and photosynthetically active radiation HEALTHY index G value
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GIS SUPPORTED HEDONIC MODEL FOR ASSESSING PROPERTY VALUE IN WEST OAKLAND, CALIFORNIA 被引量:1
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作者 ZHOU De-min XU Jian-chun GONG Hui-li 《Chinese Geographical Science》 SCIE CSCD 2006年第1期70-78,共9页
A hedonic linear regression model is constructed in this paper to estimate property value, In our model, the property value (sales price) is a function of several selected variables such as the property characterist... A hedonic linear regression model is constructed in this paper to estimate property value, In our model, the property value (sales price) is a function of several selected variables such as the property characteristics, social neighborhoods, level of neighborhood environmental contaminations, level of neighborhood crimes, and locational accessibility to jobs or services, Definitions and calculation of these variables are approached by using Geographic Information System tools, For improving estimation, gravity model is employed to measure both levels of neighborhood toxic sites and crimes; and a time-based method is used to measure the loeational accessibility rather than simple straight-line distance measurement. This study discovers that the relationship between house value and its nearby highway is nonlinear, The methodology could help policy makers assess the external effects of a property. Our model also could be used potentially to identify the current and historic trends of development caused by neighborhood or environments change in the study area. 展开更多
关键词 GIS property value neighborhood effect Hedonic Price Analysis
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Strategic Deviance,Customer Concentration and Enterprise Value——A Case Study of Agricultural Listed Enterprises 被引量:1
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作者 Pan HUANG 《Asian Agricultural Research》 2018年第4期29-36,共8页
From the perspective of strategy,this paper uses A-share agricultural listed companies( 2011-2016) as samples to study the impact of strategic deviance on enterprise value,to explore whether customer concentration pla... From the perspective of strategy,this paper uses A-share agricultural listed companies( 2011-2016) as samples to study the impact of strategic deviance on enterprise value,to explore whether customer concentration plays a mediating effect. The results show that customer concentration plays a mediating effect in the relationship between strategic deviance and enterprise value. The strategic deviance is positively correlated with customer concentration and negatively correlated with enterprise value. The management of agricultural enterprises must pay attention to the customer relationship problems caused by strategic deviance,reduce the risk of enterprises,and gradually enhance the value of enterprises. 展开更多
关键词 Strategic deviance Customer concentration Enterprise value Mediating effect
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Determination of the Critical Value of Deflection for Embedded Cylindrical Structures
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作者 刘建起 陈滨 王海艳 《China Ocean Engineering》 SCIE EI 2005年第3期519-528,共10页
An embedded cylinder is a large-diameter cylinder embedded in a soil foundation. The state of failure of such an embedded cylindrical structure shows large deflection instead of slide and overturn of the traditional g... An embedded cylinder is a large-diameter cylinder embedded in a soil foundation. The state of failure of such an embedded cylindrical structure shows large deflection instead of slide and overturn of the traditional gravity type of structure placed on a rubble base or foundation base. The critical value of deflection of the embedded cylindrical structure, which is the maximum allowable deflection for stability calculation of the cylinder, is a vital control value. Through investigation on deflection and soil pressures on an embedded cylinder by model experiments, the variations of the angle of rotation θ of a cylinder with effective anti-overturning ratio η and moment MH of thrust are discussed. On the basis of experimental study, the critical value of deflection of the cylindrical structure is proposed in the paper. Meanwhile, the formulas for calculating deflection of cylinders are derived. 展开更多
关键词 deflection of cylinder critical value of deflection effective anti-overturning ratio moment of thrust calculation of deflection
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