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Opportunity Costs of Emissions Caused by Land-Use Changes 被引量:2
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作者 S. Suyanto Andree Ekadinata +1 位作者 Muhammad Sofiyuddin Arif Rahmanullah 《Open Journal of Forestry》 2014年第1期85-90,共6页
Amid the euphoria of Reducing Emissions from Deforestation and Forest Degradation (REDD) and REDD+ discussions, the expectations of large financial gains raise the interest of all. A country, however, will only enjoy ... Amid the euphoria of Reducing Emissions from Deforestation and Forest Degradation (REDD) and REDD+ discussions, the expectations of large financial gains raise the interest of all. A country, however, will only enjoy REDD benefits if the cost of REDD is lower than the benefit. The opportunity cost analysis is an effective tool for assessing the feasibility of REDD+ since the largest portion of costs associated with REDD+ and can help to identify fair compensation for those who change their land use. The opportunity cost analysis has been exercised in Tanjung Jabung Barat (Tanjabar) district-Indonesia to examine the economic-feasibility of carbon emission reduction under different type carbon price scenarios. This study reveals a sharp decline of land-use systems with high carbon-stock and low profitability is obvious. On mineral soil, low carbon-stock and high profitability (mostly oil palm) has increased rapidly, especially in the period 2000-2009. It has become the dominant land-use system. The low-to-medium carbon stock and medium profitability land-use category increased from 1990 to 2005 but declined from 2005 to 2009. The low carbon-stock and low profitability category was constant and the proportion of the area was below 15%. The ex-ante analysis in predicting the potential for future emissions reduction in Tanjabar through REDD+ approaches shows that the cumulative emission of Tanjabar in 2020 is estimated at 61.91 Mg CO2-eq/Ha.Year, while the reduced emission by excluding all land use conversion below $5 threshold is estimated at 51.71 Mg CO2-eq/Ha.Year. This means that there is a potential for 16% emission reduction using $5/ton CO2-eq incentive. Another important finding in this study is that if the price of carbon increases by double to $10, the amount of reduced emission does not change much. This can use as a basis for determining the right amount of incentive for trade-off between economic profitability and climate change mitigation effort in Tanjabar using REDD+ scheme both at seller and buyer perspectives. 展开更多
关键词 opportunity cost LAND Use Change Carbon Emission REDDS
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Strategies for Prioritizing Ecological Construction with Consideration of Agricultural Industry Development in Northern China’s Agro- pastoral Ecotone : A Perspective of Opportunity Cost 被引量:2
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作者 Liang REN Fang SUN Ding DING 《Asian Agricultural Research》 2021年第9期6-12,19,共8页
In northern China’s agro-pastoral ecotone,there are conflicts between agricultural industry and ecological construction resource competition,and also problems urgently to be solved for economic growth and sustainable... In northern China’s agro-pastoral ecotone,there are conflicts between agricultural industry and ecological construction resource competition,and also problems urgently to be solved for economic growth and sustainable ecological improvement.Taking the development concept of"lucid waters and lush mountains being mountains of gold and silver"as the guiding principle of prioritizing ecological and green development,this paper studied the strategies for prioritizing ecological construction with consideration of economic development of agricultural industry from the perspective of opportunity cost.Through the analysis of opportunity cost,externality,and Pareto optimal theory,and using the calculation method of the unit equivalent factor value of terrestrial ecological service function,this paper calculated the ecological service value of forest,grassland,and farmland.It found that the ecological value of forest and grassland per unit area was greater than the ecological value of agricultural industry.This indicates that the opportunity cost of farmland for ecological construction was less than that of agricultural industry.Based on the theoretical and quantitative analysis,it came up with recommendations for establishing a comprehensive system for prioritizing ecological construction with consideration of agricultural industry development and establishing and improving the incentive mechanism of ecological construction. 展开更多
关键词 opportunity cost Northern China’s agro-pastoral ecotone Agricultural industry Ecological construction Coordinated development
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The Analysis and Modification of Opportunity Cost of Investment 被引量:1
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作者 Wei Lu 《Chinese Business Review》 2005年第3期72-74,共3页
We think we should use basic return rate of industry to measure the opportunity cost of capital and use the rule of Maximum NPV (Net Present Value) to modify the wrong solution in the book.
关键词 capital budget limit opportunity cost basic return rate of industry rule of Maximum NPV (Net Present Value)
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Measuring the effect of opportunity cost of time on participation in sports and exercise
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作者 Nana Kwame Anokye Subhash Pokhrel Julia Fox-Rushby 《Open Journal of Preventive Medicine》 2013年第5期380-392,共13页
Background: There is limited research on the association between opportunity cost of time and sports and exercise due to lack of data on opportunity cost of time. Using a sample of 14142 adults from Health Survey for ... Background: There is limited research on the association between opportunity cost of time and sports and exercise due to lack of data on opportunity cost of time. Using a sample of 14142 adults from Health Survey for England (2006), we develop and test a composite index of opportunity cost of time (to address the current issues with data constraint on opportunity cost of time) in order to explore the relationship between opportunity cost of time and sports participation. Methods: Probit regression models are fitted adjusting for a range of covariates. Opportunity cost of time is measured with two proxy measures: a) composite index (consisting of various indicators of wage earnings) constructed using principal component analysis;and b) education and employment, approach in the literature. We estimate the relative impact of the composite index compared with current proxy measures, on prediction of sports participation. Findings: Findings suggest that higher opportunity cost of time is associated with increased likelihood of sports participation, regardless of the time intensity of activity or the measure of opportunity cost of time used. The relative impacts of the two proxy measures are comparable. Sports and exercise was found to be positively correlated with income. Another important positive correlate of sports and exercise is participation in voluntary activity. The research and policy implications of our findings are discussed. 展开更多
关键词 Physical Activity SPORTS and EXERCISE opportunity cost of TIME Index
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Estimating the opportunity costs of avoiding oil palm-based deforestation in Indonesia:Implications for REDD
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作者 Xi Li Xufang Zhang Hongqiang Yang 《Chinese Journal of Population,Resources and Environment》 2020年第1期9-15,共7页
Reducing emissions due to deforestation is considered a low-cost option for mitigating climate change.However,the recent literature suggests higher opportunity costs because of specific deforestation drivers,which ren... Reducing emissions due to deforestation is considered a low-cost option for mitigating climate change.However,the recent literature suggests higher opportunity costs because of specific deforestation drivers,which render reducing emissions from deforestation and forest degradation(REDD+)for mitigating climate change an uncertain,less attractive,and controversial option.Indonesia is one of the largest greenhouse gas emitters.Since 1989,53.80%of its oil palm expansion has come from forestlands,which has generated a significant amount of carbon emissions.This study uses official data and results from the relevant literature to estimate the costs of oil palm-based deforestation under various scenario assumptions,including different output prices,yields,time horizons,and discount rates.We also calculate the additional cost to preserve a 1-ha forest.We demonstrate that the average opportunity cost from avoiding oil palm-based deforestation is 24.42 USD/tCO_(2)eq in Indonesia,approximately 1.3 times the 2011 EUA carbon price.Additional sums of around 5,466.90–11,042.96 USD/ha should be provided to landowners for the deforestation avoidance caused by oil palm expansion.Special attention should be given to the extensive oil palm expansion in Indonesia and the resulting high opportunity costs for achieving the REDD+​target. 展开更多
关键词 REDD+ DEFORESTATION Oil palm opportunity cost Net present value
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The Optimizing Method of Equipment Renewal Opportunity Based on Dynamic Sunk Cost
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作者 Guojie Zhao Weiwei Zhao 《Chinese Business Review》 2005年第10期41-44,70,共5页
This article brings forward a new conception of dynamic sunk cost, and then constructs a systematic model that could be used in analyzing equipment renewal opportunity. This model will do much help in solving problems... This article brings forward a new conception of dynamic sunk cost, and then constructs a systematic model that could be used in analyzing equipment renewal opportunity. This model will do much help in solving problems refer to optimizing equipment renewal opportunity in right way. 展开更多
关键词 dynamic sunk cost optimize renewal opportunity rolling analysis
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Economic Impact of Clinical Research to Research Centers and Opportunity Cost for the Reimbursement System in Turkey
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作者 Güvenc Kockaya Meral Demir +2 位作者 Pinar Daylan Kockaya Mehtap Tatar Ali Yagizüresin 《Health》 2015年第9期1124-1133,共10页
Introduction: Clinical research is a key component of drug development with a significant economic value. It has been reported that the development of a new molecule requires 10 - 15 years and costs almost $1.3 billio... Introduction: Clinical research is a key component of drug development with a significant economic value. It has been reported that the development of a new molecule requires 10 - 15 years and costs almost $1.3 billion. Around 75% of the cost is spent on the Phase I-IV clinical research process. This study aimed to show the economic value of clinical research in Turkey. Methods: Clinical trial budgets were estimated from the raw data of the Report of Istanbul Medical Faculty Clinical Research (ITFKAR). In the research, the estimated cost of drugs used in the clinical trials for the Turkish reimbursement agency (SGK) was calculated to show the cost of medicines acquired through clinical research. Results: The total budget for sponsored pharmaceutical research was $107 million in Turkey, and the government saved close to $311,096,130 during 2006-2010, due to not reimbursing the patients for the drugs in the clinical trials. Conclusion: Despite the limitations of the study, the findings are unique for Turkey. The results can lead to revisiting the importance and economic value of clinical trials in Turkey. 展开更多
关键词 Clinical Research Economic Impact REIMBURSEMENT Research Centers opportunity cost
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Agricultural Land Use Responses to the Rising Labor Opportunity Cost in Sui County,China 被引量:4
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作者 Chen Yuqi 《Chinese Journal of Population,Resources and Environment》 2010年第4期10-18,共9页
Rising labor opportunity cost is one of the most important characteristics of farmers' economic environment in present China,and brings great agricultural land use changes correspondingly.Based on the stratified r... Rising labor opportunity cost is one of the most important characteristics of farmers' economic environment in present China,and brings great agricultural land use changes correspondingly.Based on the stratified random sample of rural households in Sui County,this paper estimates the opportunity cost of farm labors,and then analyzes its effect on farmers' agricultural land use decisions.The findings show that the households with higher labor opportunity cost are more likely to reduce labor intensity and increase labor-saving input in their land use decisions.From the descriptive analysis,we also find these households always prefer grain crop planting,reduce yield-raising input or even rent out their cultivated land.As labor and yield-raising input are two essential positive factors for grain production,continuous declining of labor input and yield-raising input caused by rising labor opportunity cost may influence the grain yield per unit area in the future. 展开更多
关键词 labor opportunity cost labor intensity capital intensity yield-raising input labor-saving input
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Agricultural opportunity costs assessment based on planting suitability:a case study in a mountain county in southwest China 被引量:3
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作者 liu ju fu bin +2 位作者 wang yu-kuan lu ya-feng xu pei 《Journal of Mountain Science》 SCIE CSCD 2017年第12期2568-2580,共13页
Payment for ecosystem services(PES) has become an increasingly popular means of ecosystem conservation. Opportunity cost is an important factor to increase the investment efficiency of PES projects.However, the distri... Payment for ecosystem services(PES) has become an increasingly popular means of ecosystem conservation. Opportunity cost is an important factor to increase the investment efficiency of PES projects.However, the distribution of opportunity cost is usually unclear in mountainous regions due to the obvious environment changes. In this study, we developed a framework to assess the distribution of agricultural opportunity costs in mountainous regions and applied this method to Baoxing County, a typical mountainous county in Sichuan Province of southwest China. Planting suitability of 17 crops was assessed based on agricultural statistics and natural conditions data within a GIS environment.Agricultural opportunity cost was quantified with a weighted summation of farmers' willingness to cultivate and each crop's opportunity cost. Finally,specific agricultural opportunity cost was obtained according to the spatial areas of the protection programs and land use status. The results showed that agricultural opportunity costs of PES in Baoxing County were estimated to be more than $30 million,with a mean of 400.85 $/ha. Agricultural opportunity costs in mountainous regions displayed some obvious spatial variation and areas with lower agricultural opportunity costs could be selected as priority areas for PES. Our findings revealed that the planting suitability evaluation can make agricultural opportunity costs mapping more reasonable. It will be helpful for the PES programs implementation in mountainous regions. 展开更多
关键词 opportunity cost Planting suitability Willingness to accept Ecosystem service Spatial variation Baoxing County
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Cost of postoperative complications:How to avoid calculation errors 被引量:2
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作者 Roberto De la Plaza Llamas JoséM Ramia 《World Journal of Gastroenterology》 SCIE CAS 2020年第21期2682-2690,共9页
Postoperative complications(PC)are a basic health outcome,but no surgery service in the world records and/or audits the PC associated with all the surgical procedures it performs.Most studies that have assessed the co... Postoperative complications(PC)are a basic health outcome,but no surgery service in the world records and/or audits the PC associated with all the surgical procedures it performs.Most studies that have assessed the cost of PC suffer from poor quality and a lack of transparency and consistency.The payment system in place often rewards the volume of services provided rather than the quality of patients’clinical outcomes.Without a thorough registration of PC,the economic costs involved cannot be determined.An accurate,reliable appraisal would help identify areas for investment in order to reduce the incidence of PC,improve surgical results,and bring down the economic costs.This article describes how to quantify and classify PC using the Clavien-Dindo classification and the comprehensive complication index,discusses the perspectives from which economic evaluations are performed and the minimum postoperative follow-up established,and makes various recommendations.The availability of accurate and impartially audited data on PC will help reduce their incidence and bring down costs.Patients,the health authorities,and society as a whole are sure to benefit. 展开更多
关键词 MORBIDITY Postoperative complications costs and cost analysis Economic evaluation Healthcare costs opportunity cost Clavien-Dindo classification Comprehensive complication index
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Managing System Losses to Improve Energy Efficiency within the Electricity Company of Ghana (ECG) Limited 被引量:1
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作者 Vincent Kwame Osei-Appiah Jones Lewis Arthur 《Smart Grid and Renewable Energy》 2022年第6期121-136,共16页
The inability to achieve the target of universal access to electricity is influenced by several factors including funding limitations, the use of obsolete equipment, power theft, and system losses confronting the elec... The inability to achieve the target of universal access to electricity is influenced by several factors including funding limitations, the use of obsolete equipment, power theft, and system losses confronting the electricity distribution services of the Electricity Company of Ghana Limited (ECG). The study assessed the components of system losses within the ECG by determining and computing the percentage of system losses within ECG, examining the causes of both commercial and technical losses in ECG, and determining ways to improve energy efficiency by reducing system losses in the most cost-efficient manner. The study adopted deductive reasoning and a quantitative approach to guide data collection and analysis of the research output. A sample of 345 technical and non-technical staff of ECG in the Greater Accra Metropolis was selected from a population of 2500. Purposive, simple random, and cluster sampling techniques were used in identifying and accessing respondents for the study. Descriptive statistics were applied to measure central tendency and degrees of dispersion and the Relative Importance Index (RII) to predict criterion and predictor variables. The impact of low voltage network losses can adversely contribute to technical losses (20%) and reduce energy efficiency in power or electricity distribution companies. Non-technical losses are mainly caused by illegal connections, meter problems, and billing problems. Each of the non-technical losses contributes a maximum of 10% to system losses. Contributors to system losses at ECG are ranked first for power theft and least for lack of incentives. System losses at ECG include metering inaccuracies, bad workmanship, unmetered supply, and lengthy distribution lines, each recording a mean value of above 3.5. Measures to improve monitoring of the networks and systems at ECG and discourage power theft should include an extensive quantification, patrolling, and inspection of the entire network to assess the extent of the network and conditions relevant for the placement of systematically planned maintenance programmes. 展开更多
关键词 Network Management System losses ELECTRICITY cost Efficiency Energy Management
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Cost-benefit Analysis of Land Development Projects Based on Fuzzy Comprehensive Evaluation Model 被引量:1
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作者 Zhengben DAI Xingchen HU Haoran CHENG 《Asian Agricultural Research》 2019年第6期12-14,共3页
Ecological and environmental issues have always been the focus of government work. The economic losses caused by air pollution,water pollution,noise pollution and solid waste pollution caused by land use development p... Ecological and environmental issues have always been the focus of government work. The economic losses caused by air pollution,water pollution,noise pollution and solid waste pollution caused by land use development projects are estimated,and the total population economic losses are incorporated into project costing. Using the analytic hierarchy process,four benefit indicators and five cost indicators are selected for constructing a fuzzy comprehensive evaluation model to evaluate the cost-benefit of projects of different scales. The projects of different scales are ranked according to the level of comprehensive scores. The results show that large-scale projects are cost-effective and stable over the long term,and there are differences in the main sources of pollution-caused economic losses for projects of different scales. At last,reasonable policy suggestions are made to relevant planning and management personnel. 展开更多
关键词 Pollution-caused ECONOMIC lossES cost-BENEFIT Fuzzy COMPREHENSIVE evaluation
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Multi-QoS Guaranteed Resource Allocation for Multi-Services Based on Opportunity Costs
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作者 jin yaqi xu xiaodong tao xiaofeng 《ZTE Communications》 2018年第2期9-15,共7页
To meet the booming development of diversified services and new applications in the future, the fifth-generation mobile conmmnication system (5G) has arisen. Resources are increasingly scarce in the @namic time-vary... To meet the booming development of diversified services and new applications in the future, the fifth-generation mobile conmmnication system (5G) has arisen. Resources are increasingly scarce in the @namic time-varying of 5G networks. Allocating resources effectively and ensuring quality of service (QoS) requirements of multi-seiwices come to be a research focus. In this paper, we utilize effective capacity to build a utility function with multi-QoS metrics, including rate, delay bound and packet loss ratio. Taking advantage of opportunity cost (OC), we also propose a multi-QoS guaranteed resource allocation algm'ithm for multi-services to consider the future condition of system. In the algorithm, according to different business characteristics and the theory of OC, we propose different selection conditions for QoS users and best effort (BE) users to choose more reasonable resources. Finally, simulation results show that our proposed algorithm achieves superior system utility and relatively better fairness in multi-service scenarios. 展开更多
关键词 utility function effective capacity opportunity cost QoS guaranteed resource allocation
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Seismic Risk Assessment of Buildings in the Extended Urban Region of Athens and Comparison with the Repair Cost
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作者 A. K. Eleftheriadou A. D. Baltzopoulou A. I. Karabinis 《Open Journal of Earthquake Research》 2014年第3期115-134,共20页
A complete research of seismic risk assessment is presented herein focused on the existing build- ings of the extended urban region of Athens in Greece. The seismic risk assessment is fulfilled by discriminating the c... A complete research of seismic risk assessment is presented herein focused on the existing build- ings of the extended urban region of Athens in Greece. The seismic risk assessment is fulfilled by discriminating the current study in two approaches, probable and actual, conducting afterwards between them a comparison analysis. In the first part, a pilot methodology is developed for the seismic loss assessment in monetary terms regarding the buildings damages, consistent with the National Programme for Earthquake Management of Existing Buildings (NPEMEB). The building stock consists of typical building types of Southern Europe and refers to 750,085 buildings (18.80% of buildings in Greece) situated in the entire region of Athens according to the results of the 2000-1 statistical census. A wider research of seismic risk assessment could include direct losses of infrastructures and indirect economic losses. The evaluation of loss due to building damage in a certain region requires an assessment of both seismic hazard and vulnerability of the building stock in the study area. Four different existing damage scenarios are applied for the vulnerability assessment. The results of the seismic risk assessment for the four different aspects of the es- timated damage and the different soil conditions are presented in a map of the study region. The existing vulnerability curves corresponding to defined types of buildings have been derived from the National Technical Chamber of Greece and also from recently developed DPMs. The last DPMs were obtained in a previous research (Eleftheriadou, 2009) from the process of a created damage database after the 7th of September 1999 Parnitha’s earthquake and comprised 180,945 buildings which developed damage of varying degree, type and extent. In the second part of the research, the seismic risk is evaluated from the available data regarding the mean statistical repair/ strengthening or replacement cost for the total number of damaged structures (180,427 buildings) after the same (1999 Parnitha’s) seismic event. Data regarding the compatible (budget approved according to the ministry’s provisions) repair cost has been collected. The structural losses in monetary terms for the 180,427 buildings damaged structures are evaluated equal to 2450.0 Μ€, 1887.8 Μ€ and 2118.9 Μ€ based on the previously mentioned statistical seismic risk data. The statistically derived repair cost for Attica is compared with the results of the economic loss esti- mation for buildings using the aforementioned risk assessment methodology. From the analysis results, the seismic scenario based on the recently developed DPMs (Eleftheriadou, 2009) pre- sented the better correlation (2627.77 M€) with the total statistically evaluated repair cost (2450.02 M€). It is important to stress that the inclusion of the coefficient parameter S overes- timates significantly the seismic losses. The last result should be taken into consideration in future risk researches. The comparison of the estimated economic loss with the statistical repair cost calibrates the reliability of the commonly used risk assessment method and serves in the im- provement of seismic security prioritizing the criteria for seismic rehabilitation programmes of existing buildings. 展开更多
关键词 SEISMIC VULNERABILITY SEISMIC Risk Damage SCENARIO ECONOMIC loss REPAIR cost
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Analysis of Appraising Agricultural Intangible Asset Value by Cost Method
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作者 LI Xiao-juan Hebei College of Finance,Baoding 071051,China 《Asian Agricultural Research》 2010年第8期4-7,共4页
On the basis of describing the connotation of agricultural intangible asset and cost method,the technical ideas of appraising by cost method are introduced.The article analyzes the advantages(simple appraisal principl... On the basis of describing the connotation of agricultural intangible asset and cost method,the technical ideas of appraising by cost method are introduced.The article analyzes the advantages(simple appraisal principle and easy to understand and grasp;overall consideration of various factors related to appraisal result value) and disadvantages(high appraisal cost;difficult to appraise and grasp various appraisal factors) of appraising by cost method.The article also summarizes the precondition of appraising by cost method:it is applicable to appraise the agricultural intangible asset which can be reproduced and afresh developed.Based on the cognition of agricultural intangible asset and the relevant rules of Ministry of Finance on appraisal of intangible asset by using cost method,the model of appraising agricultural intangible asset by cost method is constructed.That is:agricultural intangible asset value = replacement cost of agricultural intangible asset ×newness rate + opportunity cost of agricultural intangible asset.Determine and analyze parameters of the model,in order to offer references for appraisers to appraise agricultural intangible asset value more reasonably. 展开更多
关键词 cost METHOD AGRICULTURAL INTANGIBLE ASSET Replacem
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Analysis of Road Traffic Accident Costs in Sudan Using the Human Capital Method
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作者 Adam I. A. Mofadal Kunnawee Kanitpong 《Open Journal of Civil Engineering》 2016年第2期203-216,共14页
In this study, we used the Human Capital (HC) accident analysis method, to determine the road traffic accident costs in Sudan in two successive years (2010 and 2011) with slight modifications to the recommended and kn... In this study, we used the Human Capital (HC) accident analysis method, to determine the road traffic accident costs in Sudan in two successive years (2010 and 2011) with slight modifications to the recommended and known framework in the way it handles currently and future accident cost components. We evaluated and compared the significance and impact of the economic loss caused by road traffic accidents in Sudan using detailed information on road traffic accident casualties, classified by severity level, vehicle type, and other key parameters such as discount rates and medical and insurance information for Sudan in its entirety. The total cost of road traffic accidents in Sudan in 2010 was estimated at US $391 million, which represents 0.57% of the Gross Domestic Product (GDP), while in 2011 the cost was calculated to reach US $413 million, representing 0.62% of GDP. Findings show that the amount of accident costs is estimated to a certain extent at less than 1% of the total GDP of the country in the two estimation years, but we believe that the evaluation process used fulfilled the eligibility criteria of HC studies and that the produced values for Sudan are valid and reliable. Unit costs for each crash severity level were also estimated in the two years such as death, disability, serious injury, slight injury, and vehicle damage. Death or fatality was equal to US $38,932 and 39,508;disability was equal to US $43,113 and US $45,165;serious injury was equal to US $6963 and US $7596;slight injury was equal to US $2570 and US $3198 and vehicle damage only was equal to US $2268 and US $2579 in the assessment years 2010 and 2011, respectively. 展开更多
关键词 Road Traffic Accident Accident costs Human Capital loss in Quality of Life SUDAN Accident Severity Level
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城市更新的机会成本和边际成本
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作者 刘迪 《城市规划》 CSCD 北大核心 2024年第5期21-29,共9页
城市更新上升为国家意志,但更新理论对“更新起点决策”和“更新终点决策”两个更新基本问题研究处于空白,对更新实践的支撑力和解释力不足。从现有更新研究中的两个误区入手,指出现有研究对更新起点和更新终点的论断与现实情况存在落差... 城市更新上升为国家意志,但更新理论对“更新起点决策”和“更新终点决策”两个更新基本问题研究处于空白,对更新实践的支撑力和解释力不足。从现有更新研究中的两个误区入手,指出现有研究对更新起点和更新终点的论断与现实情况存在落差,借助微观经济学和超边际理论的分析工具,从机会成本和边际成本角度构建了“更新起点决策”和“更新终点决策”两个理论模型,通过对两个模型的拟合,形成了“起点-终点全过程决策”框架,依据该框架提出了“城市更新精明决策”思路,指出改进起点决策的“更新专业化分工”和“更新起点信贷”策略,改进终点决策的“设施触媒”和“更新底线管控”策略。为更新决策的底层逻辑分析和决策改进提供了新研究视角。 展开更多
关键词 城市更新 更新决策 机会成本 边际成本 更新起点 更新终点 精明更新
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在线问答社区学生用户信息资源隐藏行为的影响因素研究
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作者 张芳 袁美琪 《情报探索》 2024年第8期34-40,共7页
[目的/意义]研究信息资源付费如何影响学生用户信息资源隐藏行为,为减少在线问答社区信息资源隐藏行为的相关理论与实践提供参考。[方法/过程]针对在线问答社区学生用户,采用问卷调查法收集了216份有效问卷,构建信息资源付费影响在线问... [目的/意义]研究信息资源付费如何影响学生用户信息资源隐藏行为,为减少在线问答社区信息资源隐藏行为的相关理论与实践提供参考。[方法/过程]针对在线问答社区学生用户,采用问卷调查法收集了216份有效问卷,构建信息资源付费影响在线问答社区学生用户信息资源隐藏行为的链式中介模型,基于资源保存理论探究其内部影响机理,并探讨感知成本和感知损失在该模型中的双中介作用。[结果/结论]信息资源付费直接正向影响在线问答社区学生用户信息资源隐藏行为;信息资源付费分别以感知成本和感知损失为中介变量来正向影响在线问答社区学生用户信息资源隐藏行为。 展开更多
关键词 信息资源付费 感知成本 感知损失 学生用户 隐藏行为
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互联网使用如何降低女性生育意愿? 被引量:1
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作者 李舜 《当代经济管理》 北大核心 2024年第1期73-83,共11页
低生育率问题是党和国家亟须解决的重点问题。在互联网高度普及的现实背景下,探明互联网使用在低生育率现象形成过程中产生的作用,有利于政府精准施策,具有重要的现实意义。文章基于CGSS2013、2015、2017的数据,使用泊松回归模型,研究... 低生育率问题是党和国家亟须解决的重点问题。在互联网高度普及的现实背景下,探明互联网使用在低生育率现象形成过程中产生的作用,有利于政府精准施策,具有重要的现实意义。文章基于CGSS2013、2015、2017的数据,使用泊松回归模型,研究了互联网使用对女性生育意愿的影响。研究发现,互联网使用通过增加女性兼职行为,从而提高女性收入,进而提高女性生育成本和传递有关家庭、婚姻的负面信息,挤出夫妻之间的共同闲暇时间,从而降低婚姻稳定性等两条途径降低了女性生育意愿。异质性分析表明,互联网使用影响女性生育意愿存在户籍类型、就业部门、政治身份、年龄等的异质性,互联网使用显著降低了城市、非党员、非国有部门女性的生育意愿,对18~24岁女性生育意愿的抑制作用更大。文章为互联网普及背景下我国低生育率社会的形成提供了新的解释,为信息时代人口公共政策制定提供了经验证据。 展开更多
关键词 互联网使用 女性生育意愿 机会成本 婚姻稳定性
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全球入侵植物的经济成本评估 被引量:1
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作者 赵光华 高明龙 +4 位作者 王朵 范世奇 唐健 孙阔 温玄烨 《草业学报》 CSCD 北大核心 2024年第5期16-24,共9页
植物是入侵生物中种类和数量最多的类群,对入侵植物开展经济成本评估可为后续风险管理和相关政策的制定提供参考依据。本研究基于InvaCost数据库评估获得了1970-2017年全球入侵植物的经济成本,研究结果表明:1)入侵植物的保守经济成本为1... 植物是入侵生物中种类和数量最多的类群,对入侵植物开展经济成本评估可为后续风险管理和相关政策的制定提供参考依据。本研究基于InvaCost数据库评估获得了1970-2017年全球入侵植物的经济成本,研究结果表明:1)入侵植物的保守经济成本为1943.65亿美元,年均40.49亿美元,其中,直接经济损失达1004.68亿美元,占比为51.69%;2)在64个国家和地区中,美国的经济成本最高,其次为澳大利亚,我国208.31亿美元(1407.07亿人民币)排名第三。凤眼莲是全球最昂贵的入侵植物种类,其危害所产生的成本高于排名5~10名的入侵植物成本之和;3)过去的近50年里,入侵植物的经济成本呈上升趋势,模型测算2017年入侵植物的可能成本为34.38亿~104.52亿美元,最高置信值为77.25亿美元。本研究有助于加深对入侵植物危害严重性的客观认识,可为我国开展更为积极的入侵植物治理提供科学依据。 展开更多
关键词 入侵植物 经济成本 Invacost数据库 生物灾害损失评估
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