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Comprehensive evaluation and spatial-temporal evolution characteristics of urban resilience in Chengdu-Chongqing Economic Circle
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作者 Xin Li Shuyi Zhang +1 位作者 Rongxi Ren Yafei Wang 《Chinese Journal of Population,Resources and Environment》 2024年第1期58-67,共10页
To clarify the connotations and extensions of urban resilience,this study focuses on the Chengdu-Chongqing Economic Circle with 16 cities as research subjects.A comprehensive evaluation index system was constructed to... To clarify the connotations and extensions of urban resilience,this study focuses on the Chengdu-Chongqing Economic Circle with 16 cities as research subjects.A comprehensive evaluation index system was constructed to measure the resilience of each city from 2003 to 2020.The spatial-temporal evolution characteristics were analyzed using Kernel density estimation,standard deviation ellipse,and spatial Markov chain analysis,and the spatial Tobit model was introduced to discover the influencing factors.The results indicate the following:①Urban resilience in the Chengdu-Chongqing Economic Circle displays an upward trend,with the center of gravity moving to the southwest,and the polarization phenomenon intensifying.②The urban resilience level in a region has certain spatial and geographical dependence,while the probability of urban resilience transfer differs in adjacent cities with different resilience levels.③Urban centrality,economic scale,openness level,and financial development promote urban resilience,whereas government scale significantly inhibits it.Finally,this paper proposes countermeasures and suggestions to improve the urban resilience of the Chengdu-Chongqing Economic Circle. 展开更多
关键词 Chengdu-chongqing economic Circle Urban resilience Spatial-temporal evolution Driving factor
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Evaluation of Economical and Intensive Use of Construction Land in a County Town:A case study of Wan’an County,Ji’an City
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作者 YU Zhijie 《Journal of Landscape Research》 2024年第1期51-54,共4页
Taking the changes of construction land in Wan’an County over the years as the research object,the quantity and spatial characteristics of construction land in Wan’an County were analyzed,and the overall situation a... Taking the changes of construction land in Wan’an County over the years as the research object,the quantity and spatial characteristics of construction land in Wan’an County were analyzed,and the overall situation and regional differences of construction land utilization in Wan’an County were revealed.From the aspects of main influencing factors such as land use structure,land use intensity,land input intensity and output benefit,an evaluation indicator system was established to evaluate the economical and intensive use level of construction land in Wan’an County.The results show that the score of the economical and intensive use level of construction land in Wan’an County was 56.92,which was the lowest among all the districts and counties in Ji’an City.Based on the evaluation results,the corresponding economizing and intensive strategies were put forward,and the safeguard measures for its implementation were explored.The purpose is to provide some support for the preparation of territorial spatial planning,the delineation of urban development boundaries,and the potential exploitation of construction land stock,hoping to improve the utilization efficiency and benefit of construction land in Wan’an County,and promote the economic growth of Wan’an County to the stage of high-quality development. 展开更多
关键词 Construction land economical and intensive utilization evaLUATION
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Evaluation on Coordination between Grassland Ecological Environment and Economic Development 被引量:10
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作者 王晓芳 宗刚 《Agricultural Science & Technology》 CAS 2010年第1期163-166,共4页
Taking grassland resources in Nagqu District of Tibet as example,the evaluation index system of environment and economy coordination degree was set up according to coordination degree evaluation model,and environment ... Taking grassland resources in Nagqu District of Tibet as example,the evaluation index system of environment and economy coordination degree was set up according to coordination degree evaluation model,and environment economic system coordination degree of 11 counties in Nagqu District was analyzed by using coordination functions. 展开更多
关键词 Grassland environmental system economic system Coordination degree
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Economic Evaluation on "Planting Three to Produce Four" High-yielding Project of Super Hybrid-rice in Hunan
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作者 邓文 彭既明 +4 位作者 刘英 金龙新 刘晗 刘军 黄振国 《Agricultural Science & Technology》 CAS 2015年第9期2048-2054,2069,共8页
The research conducted investigation and survey on 186 farm households in 2014 and carried out economic evaluation on "planting three to produce four" highyielding project of super hybrid rice. The results showed th... The research conducted investigation and survey on 186 farm households in 2014 and carried out economic evaluation on "planting three to produce four" highyielding project of super hybrid rice. The results showed that the project of "planting three to produce four" performed significantly in terms of increasing yields and incomes. For example, per unit area yield of one-season late hybrid rice and middleseason hybrid rice proved the highest, and net income from middle-season rice in Longhui was the highest. It is obvious that to increase per unit yield is key for improving net incomes and to reduce machine fees and worker fees is crucial for decreasing fees. 展开更多
关键词 Super hybrid-rice "Planting three to produce four" economic evaluation HUNAN
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纳米硅溶胶−EVA−粉煤灰水泥基复合浆材配比正交优化及对其物性的影响
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作者 沈玉旭 柴肇云 +6 位作者 孙浩程 刘向御 郭俊庆 肖畅 李天宇 辛子朋 史沁彬 《煤炭学报》 EI CAS CSCD 北大核心 2024年第6期2643-2659,共17页
针对传统水泥基浆材不能满足煤矿大变形巷道注浆加固实际需求的难题,通过添加纳米硅溶胶、乙烯−醋酸乙烯共聚物(EVA)和粉煤灰对普通硅酸盐水泥进行改性获得高性能复合浆材。采用正交试验和极差分析法系统研究复合浆材物理力学性能的变... 针对传统水泥基浆材不能满足煤矿大变形巷道注浆加固实际需求的难题,通过添加纳米硅溶胶、乙烯−醋酸乙烯共聚物(EVA)和粉煤灰对普通硅酸盐水泥进行改性获得高性能复合浆材。采用正交试验和极差分析法系统研究复合浆材物理力学性能的变化规律,确定最优配比,并进一步分析最优配比复合浆材与纯水泥的物性差异,构建复合浆材的水化反应机理模型,阐明其加固破碎岩石的力学特性。研究结果表明,复合浆材最优配比为:水灰比0.7,粉煤灰掺量15%,硅溶胶掺量2%,EVA掺量7.5%;相较于纯水泥,复合浆材流变性略有下降,但浆液稳定性、力学性能等均有显著提升,初凝时间缩短了38.9%,终凝时间缩短了53.8%,析水率降低了60%,结石率提高了3.3%,单轴抗压强度提高了39.1%,抗拉强度提高了97.2%,拉压比提高了41.7%;硅溶胶和粉煤灰在不同时期与Ca(OH)2发生火山灰反应生成更多水化硅酸钙(C-S-H)和水化铝酸钙(CA-H),促进复合浆材的水化反应,并加速EVA成膜,使结石体更加致密;复合浆材注入量和胶结体单轴抗压强度均随注浆压力的增大而增加,随Talbot指数的增加,抗压强度先增大后减小,破坏形式多呈鼓状,剪胀变形明显;当注浆压力大于2 MPa,Talbot指数为0.5时,胶结体强度较大,破坏较小。本研究为水泥基复合浆材早期强度、增韧改性提供了可行途径。 展开更多
关键词 纳米硅溶胶 eva 粉煤灰 普通硅酸盐水泥 正交试验
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基于EVA的物流企业并购动因及绩效分析——以S公司并购J公司为例
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作者 王冶琦 张芯卉 +1 位作者 徐静 郑中宇 《物流科技》 2024年第22期30-32,共3页
近年来,国内互联网经济稳步增长,网络购物平台的崛起,带动了物流行业的迅猛发展。市场也对物流企业提出了更高的要求,物流企业为抢占更多市场份额,纷纷选择并购。并购已成为物流企业发展的重要手段。文章以S公司跨国并购J公司为例,分析... 近年来,国内互联网经济稳步增长,网络购物平台的崛起,带动了物流行业的迅猛发展。市场也对物流企业提出了更高的要求,物流企业为抢占更多市场份额,纷纷选择并购。并购已成为物流企业发展的重要手段。文章以S公司跨国并购J公司为例,分析物流行业并购动因及其对绩效的影响,通过计算S公司近几年的EVA数据,分析企业并购对绩效产生的影响并针对企业的现状提出发展建议,从行业角度出发,助力物流企业实现突破式增长,并为其他物流企业并购提供参考。 展开更多
关键词 经济增加值(eva) 绩效分析 跨国并购
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Prevalence of ruminants fascioliasis and their economic effects in Kashan,center of Iran 被引量:7
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作者 Hassan Khoramian Mohsen Arbabi +3 位作者 Mahmood Mahami Osqoi Mahdi Delavari Hossein Hooshyar Mohammarreza Asgari 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2014年第11期918-922,共5页
Objective:To determine the prevalence and economic losses of Fasciola spp.isolates and costs incurred due to liver condemnation from ruminants in Kashan region,center of Iran from 2012 to 2013.Methods:In this cross-se... Objective:To determine the prevalence and economic losses of Fasciola spp.isolates and costs incurred due to liver condemnation from ruminants in Kashan region,center of Iran from 2012 to 2013.Methods:In this cross-sectional study,a total number of 251 325 slaughtered sheep,goats and cattle(88939 sheep.151 924 goats and 10462 cattle) were examined via necropsy for fasciolasis in industrial Kashan abattoirs located in center of Iran.The average weight was calculated as 1 000 g for sheep,900 g for goat and 5000 g for cattle in this study region.Based on market value,the average price of a kilo gram of normal liver at Kashan city during the study period was 8 USD.The amount of main nutrients and vitamins elimination in liver contaminated to fascioliasis was determined.Results:Overall 3.28%of the livers were found to be infected.For total number of sheep,goats and cattle slaughtered annually in region study,it was estimated that 7505 livers were infected and total annual economic losses of fascioliasis of studied animals was 41 784 USD(based on market prices in study period).Of this.23 360 USD,30240 USD and 15400 USD were associated with the fascioliasis of sheep,goats and cattle,respectively.Conclusions:This study indicated that the Fasciola sp.clearly remains prevalent and causes considerable economic losses in study region in sheep,goats and cattle and presumably,other areas and hosts of Iran,providing baseline data for the future monitoring of this potentially important parasitic infection in the country. 展开更多
关键词 economic losses CATTLE SHEEP GOAT PRevaLENCE FASCIOLIASIS
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基于EVA模型的企业价值评估研究——以煌上煌为例
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作者 孙伟艳 袁霆啸 《现代商业》 2024年第4期169-172,共4页
当前,我国经济已进入高质量发展阶段,对构建高质量的社会主义市场经济体制提出了新要求,市场对企业价值评估的重视程度与日俱增。近年来,卤制品市场规模逐年上升,本文选取卤制品代表性企业煌上煌为例,采用EVA模型对其企业价值进行评估,... 当前,我国经济已进入高质量发展阶段,对构建高质量的社会主义市场经济体制提出了新要求,市场对企业价值评估的重视程度与日俱增。近年来,卤制品市场规模逐年上升,本文选取卤制品代表性企业煌上煌为例,采用EVA模型对其企业价值进行评估,并与评估基准日的市值进行对比,从而对投资者做出决策起到一定的参考作用。 展开更多
关键词 企业价值评估 eva模型 卤制品企业
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An economic evaluation method of coalbed methane resources during the target selection phase of exploration 被引量:5
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作者 Dong-Kun Luo Liang-Yu Xia 《Petroleum Science》 SCIE CAS CSCD 2015年第4期705-711,共7页
Because forecasting a development program during the target selection phase of exploration for coalbed methane (CBM) is impossible, the conventional method that relies on a conceptual (or detailed) development pro... Because forecasting a development program during the target selection phase of exploration for coalbed methane (CBM) is impossible, the conventional method that relies on a conceptual (or detailed) development pro- gram cannot be used during the economic evaluation of CBM resources. Hence, this study focuses on establishing an economic evaluation model based on the characteristics of the target selection phase. The discounted cashflow method is applied to the construction of the model with the assumption that there is a uniform distribution of produc- tion wells. The computational error generated by the assumption is corrected by introducing a correction factor based on the production profile of single CBM wells. The case study demonstrates that the blocks lacking economic value can be screened out, and the most advantageous targets can be found by computing the resource values in the best- and worst-case scenarios. This technique can help to reduce wasted investments and improve the quality of decision-making in selecting targets for exploration. 展开更多
关键词 Coalbed methane Exploration targetselection economic evaluation Scenario analysis
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Studies on Technique of Reducing Methane Emission in a Rice-Duck Ecological System and the Evaluation of Its Economic Significance 被引量:5
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作者 XIANG Ping-an HUANG Huang +3 位作者 HUANG Mei GAN De-xin ZHOU Yan FU Zhi-qiang 《Agricultural Sciences in China》 CAS CSCD 2006年第10期758-766,共9页
The rice-duck ecological system is one of the major practices of the traditional Chinese agriculture. A study on the effect of reducing methane emission using this practice provided theoretical and practical basis for... The rice-duck ecological system is one of the major practices of the traditional Chinese agriculture. A study on the effect of reducing methane emission using this practice provided theoretical and practical basis for further development and utilization of this classical agricultural technique. The effect of reducing methane emission and the economic benefits of rice-duck ecological system were studied by carrying out a field experiment and by using economic methodology. The daily variation of CH4 emission in late rice paddy field was basically consistent with the daily variation of atmospheric temperature. The highest emission occurred at the full tillering stage of late rice with a rate of 24.1 or 32.2 or 40.5 mg m^-2 h^-1 in no-tillage area with duck and no-tillage area without duck and conventional-tillage area without duck, respectively. The inhibition of methane emission was apparently effective in the rice-duck ecological system during the initial tillering stage and the full tillering stage. Compared to the no-tillage area without duck, methane emission decreased by 2.333 g m^-2. Compared to the conventional-tillage area without duck, methane emission decreased by 4.723 g m^-2. During the production period of late rice, the amount of methane emission in no-tillage area with duck was 3.373 g m^-2 lesser than that of no-tillage area without duck, and 5.59 g m^-2 less than that of conventional-tillage without duck area. The economic significance was analyzed. Farmers adopting the rice-duck ecological system obtained 2 166 and 4 207 RMB yuan ha^-1 more income than those who adopted a no-tillage without duck technique or conventional-tillage without duck technique, respectively. In addition to the reduction of the environmental pollution by methane emission, the farmers who adopted the rice-duck ecological system achieved economic benefits of 5 000 RMB yuan ha^-1, which was 2 206 and 4 274 RMB yuan ha^-1 more than those who adopted a no-tillage without duck technique and a conventional-tillage without duck technique, respectively. The rice-duck ecological system not only increased the economic benefits for farmers, but also reduced methane emission in rice paddy field. A sustainable agricultural production mode was formed. 展开更多
关键词 NO-TILLAGE late rice rice-duck system methane emission mitigation options economic evaluation
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Economic evaluation of cervical cancer screening strategies in urban China 被引量:4
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作者 Li Ma Yuying Wang +11 位作者 Xiaohong Gao Yi Dai Yu Zhang Zhaojing Wang Xiaoxia Wang Limin Wang Jing Jiang Xinhua Jing Chunxia Yang Fanghui Zhao Jinghe Lang Youlin Qiao 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2019年第6期974-983,共10页
Objective:This study evaluated the feasibility of different cervical cancer screening strategies in urban China.Methods:A Markov model was constructed to simulate a hypothetical cohort of 100,000 females aged 30-59 ye... Objective:This study evaluated the feasibility of different cervical cancer screening strategies in urban China.Methods:A Markov model was constructed to simulate a hypothetical cohort of 100,000 females aged 30-59 years in a 20-year period.Screening strategies included liquid-based cytology(LBC)every three years,human papillomavirus(HPV)DNA testing every three and five years,respectively,and a combination of HPV DNA testing and LBC(HPV+LBC)every three and five years,respectively.Model outcomes included cumulative incidence over 20 years,cumulative risk of cervical cancer,costs,life year saved(LYS),quality-adjusted life years(QALYs)and benefits.The cost-effectiveness ratios(CERs),incremental cost-effectiveness ratios(ICERs),costutility ratios(CURs),and benefit-cost ratios(BCRs)were used as outcomes in the health economic evaluation analysis.Univariate sensitivity analyses were performed to examine the stability of the results.Results:The cumulative incidence of the five screening strategies ranged from 833.02 to 1,158.07 cases per100,000 females.HPV DNA testing was most effective in reducing the cumulative risk of cervical cancer,saving life years and QALYs and gaining benefits.The CERs of HPV DNA testing every three and five years,and LBC every three years were considered to be very cost-effective if they were below China's GDP per capita.The CERs of HPV+LBC were considered to be cost-effective if they were below three times GDP per capita.The incremental cost-effectiveness analysis showed that HPV DNA testing every three and five years,LBC every three years and HPV+LBC every five years were dominant strategies.Conclusions:The findings of this study indicated that HPV DNA testing every five years or LBC every three years should be recommended in urban China. 展开更多
关键词 Cervical cancer Markov model economic evaluation
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Methane and Nitrous Oxide Emissions from Rice-Duck and Rice-Fish Complex Ecosystems and the Evaluation of Their Economic Significance 被引量:13
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作者 YUAN Wei-ling CAO Cou-gui LI Cheng-fang ZHAN Ming CAI Ming-li WANG Jin-ping 《Agricultural Sciences in China》 CAS CSCD 2009年第10期1246-1255,共10页
Rice-duck (RD) and rice-fish (RF) ecological systems are major complex planting and breeding models of rice paddy fields in southern China. Studying the methane (CH4) and nitrous oxide (N2O) emissions and thei... Rice-duck (RD) and rice-fish (RF) ecological systems are major complex planting and breeding models of rice paddy fields in southern China. Studying the methane (CH4) and nitrous oxide (N2O) emissions and their economic value from these two ecosystems can provide theoretical and practical basis for further development and utilization of these classical agricultural techniques. CH4 and N2O emissions from RD and RF ecological systems were measured in situ by using static chambers technique. Using global warming potentials (GWPs), we assessed the greenhouse effect of CH4 and N2O and their economic value. Results showed that the peaks of CH4 emission fluxes from RD and RF appeared at full tillering stage and at heading stage, and the average emission fluxes were significantly (P〈 0.05) lower than that from CK. N2O fluxes remained low when the field is flooded and high after draining the water. Compared with CK, the total amount of N2O emissions was significantly (P〈0.05) higher and slightly lower than those from RD and RF, respectively. In 2006 and 2007, the total greenhouse effect of CH4 and N20 from RD and RF were 4 728.3 and 4 611 kg CO2 ha^-1, 4 545 and 4 754.3 kg CO2 ha^-1, respectively. The costs of greenhouse effect were 970.89 and 946.81 RMB yuan ha^-1, and 933.25 and 976.23 RMB yuan ha^-1, respectively, which were significant lower than those from CK (5 997.6 and 5 391.5 RMB yuan ha^-1). Except for the environment cost of CH4 and N2O, the economic benefits from RD and RF were 2 210.64 and 4 881.92 RMB yuan ha^-1; 3 798.37 and 5 310.64 RMB yuan ha^-1, respectively, higher than those from CK. Therefore, RD and RF complex ecological planting and breeding models can effectively decrease and control CH4 and N2O emissions, and they are two of the effective strategies to reduce greenhouse gases from rice paddy fields and contribute in alleviating global warming. Thus, their adoption is important to the environment together with their economy benefits. 展开更多
关键词 methane emission nitrous oxide emission rice-duck complex ecosystem rice-fish complex ecosystem greenhouse effect economic benefit
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Evaluation of the Economical and Intensive Use of Industrial Land in Chizhou Economic and Technological Development Zone 被引量:3
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作者 Rui LIU 《Asian Agricultural Research》 2014年第10期85-90,共6页
Based on the subdivision of industrial land in Chizhou Economic and Technological Development Zone,this paper builds the evaluation indicator system for the economical and intensive use of industrial land in the devel... Based on the subdivision of industrial land in Chizhou Economic and Technological Development Zone,this paper builds the evaluation indicator system for the economical and intensive use of industrial land in the development zone,to analyze the current situation of economical and intensive use of industrial land. The results show that the levels of economical and intensive use of industrial land vary in the development zone; the factors affecting the intensive degree of various industries also vary; the industry in Chizhou Economic and Technological Development Zone is still in the transition phase from inefficient use to low level of use to intensive use. 展开更多
关键词 INDUSTRIAL LAND economical and INTENSIVE use evalu
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Economic Value Evaluation of Wetland Service in Yeyahu Wetland Nature Reserve,Beijing 被引量:9
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作者 ZHU Lin CHEN Yun +3 位作者 GONG Huili JIANG Weiguo ZHAO Wenji XIAO Yanfang 《Chinese Geographical Science》 SCIE CSCD 2011年第6期744-752,共9页
Based on multi-source data,this paper evaluated the economic value of ecological services in the Yeyahu Wetland Nature Reserve,Beijing,China.The ecological services of wetland included gas regulation,water quality im-... Based on multi-source data,this paper evaluated the economic value of ecological services in the Yeyahu Wetland Nature Reserve,Beijing,China.The ecological services of wetland included gas regulation,water quality im-provement,biodiversity maintenance,erosion control,water supply,recreational opportunity,raw material supply and existence value.Multiple conventional evaluation methods were used to calculate the value of eight wetland services.The results showed that significant values came from biodiversity maintenance and recreational opportunity.The main reasons were as follows.Firstly,Yeyahu Wetland Nature Reserve was the habitat for migrant birds,and government had payed more efforts to protect precious birds.Secondly,the population is large in Beijing.People enjoyed going outside and enjoyed the natural and artificial wetland scenes.At the same time,most people were prepared to pay for wetland conservation.The decline of vegetation cover made the economic value of erosion control the lowest.While the shrink of water resource and the deteriorative water quality caused the economic value of water supply lower.The evaluation results could help decision-makers understand the present status of the Yeyahu Wetland Nature Reserve and provide a scientific basis for strategic decision. 展开更多
关键词 economic value evaluation wetland service Yeyahu Wetland Nature Reserve BEIJING
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The need for a new framework for the economic evaluation of health services in a national health scheme 被引量:1
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作者 Jeff R. Richardson John McKie Kompal Sinha 《Health》 2010年第9期1120-1133,共14页
The normative theory of economic evaluation and its welfare theoretic basis are deeply problematical and result in recommendations which are potentially unfair. The root cause of the problem is the set of assumptions ... The normative theory of economic evaluation and its welfare theoretic basis are deeply problematical and result in recommendations which are potentially unfair. The root cause of the problem is the set of assumptions behind the theory which posit behaviours and motivations that are not universal, and which exclude other behaviours and motivations that are potentially important. As falsification of assumptions may be evaded indefinitely this paper presents an alternative critique. We commence with six an- omalies with the theory which are attributable to the assumptions. The first three—the net present value criterion, the willingness to pay criterion and moral hazard—arise from welfare theory. The remaining three are associated with the present definition of cost, the concept of efficiency and the omission of sharing, which are common to most economic evaluation. We argue that these anomalies are indicative of a defective core theory and that they are equivalent to observations that conflict with a positive theory. In the final section we outline and illustrate a more general framework for decision making that is capable of overcoming the ano- malies we discuss. 展开更多
关键词 economic evaluation economic COSTS WELFARE Theory Empirical ETHICS Cost BENEFIT Analysis
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Epidemiology,management,and economic evaluation of screening of gallstone disease among type 2 diabetics:A systematic review 被引量:1
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作者 Lujie Chen Yu-Ting Peng +1 位作者 Fu-Li Chen Tao-Hsin Tung 《World Journal of Clinical Cases》 SCIE 2015年第7期599-606,共8页
The knowledge of gallstone disease(GSD) is crucial to manage this condition when organizing screening and preventive strategies and identifying the appropriated clinical therapies. Although cholecystectomy still be th... The knowledge of gallstone disease(GSD) is crucial to manage this condition when organizing screening and preventive strategies and identifying the appropriated clinical therapies. Although cholecystectomy still be the gold standard treatment for patients with symptomatic GSD, expectant management could be viewed as a valid therapeutic method for this disorder. If early treatment of GSD decreases the morbidity or avoids further cholecystectomy, it may save clinical care costs in later disease periods sufficiently to offset the screening and early treatment costs. In addition, whether routine screening for GSD is worthwhile depends on whether patients are willing to pay the ultrasonography screening cost that would reduce the risk of cholecystectomy. In this review we discuss the epidemiology, management, and economic evaluation of screening of GSD among type 2 diabetics. 展开更多
关键词 GALLSTONE disease EPIDEMIOLOGY MANAGEMENT economic evaluation Type 2 DIABETES
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The dynamic economic evaluation method of shale gas resources 被引量:2
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作者 Gang-yi Zhai Xiang-lin Chen +4 位作者 Xiang-hua Xia Zhi Zhou Tian-xu Guo Guo-heng Liu Rui-han Yuan 《China Geology》 2019年第2期211-217,共7页
At present, most shale gas exploration and development areas in China are difficult to provide sufficient and effective production data to support economic evaluation, since they are still in the initial stage of low ... At present, most shale gas exploration and development areas in China are difficult to provide sufficient and effective production data to support economic evaluation, since they are still in the initial stage of low exploration level. In addition, ecological and environmental factors are not taken into account in the evaluation process, which does not meet the needs of green energy development of China. Aiming at above problems, the dynamic economic evaluation method of shale gas resources based on calculus principle is proposed. The Arps hyperbolic decreasing curve model will be used in the evaluation of single shale gas well production, which can evaluate single well production of shale gas by fitting the existing dynamic production data to generate the production decreasing curve. Therefore, the variation regularity of the cumulative production of single well shale gas within the study area can be obtained by the model mentioned above. According to the variation regularity of the cumulative production obtained from the Arps hyperbolic decreasing curve model, the recovery period of single well cost, ultimate economic life and the ultimate economic resource can be evaluated dynamically by analyzing the variation regularity of the cumulative sales revenue and cumulative input cost of single shale gas well. Then the evaluation result can be further extend to the whole evaluation areas, in order to analyze shale gas resources ’ economic value in evaluation regions under different shale gas price conditions. The results of the above evaluation methods are not only conducive to improving the economic benefits of relative shale gas development enterprises, but also provide a basis for the national energy strategy deployment. 展开更多
关键词 SHALE gas evaluation method economic RESOURCES Single WELL COST economic LIFE
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Lithofacies modeling by multipoint statistics and economic evaluation by NPV volume for the early Cretaceous Wabiskaw Member in Athabasca oilsands area, Canada 被引量:1
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作者 Kwang Hyun Kim Kyungbook Lee +2 位作者 Hyun Suk Lee Chul Woo Rhee Hyun Don Shin 《Geoscience Frontiers》 SCIE CAS CSCD 2018年第2期441-451,共11页
The static modeling and dynamic simulation are essential and critical processes in petroleum exploration and development. In this study, lithofacies models for Wabiskaw Member in Athabasca, Canada are generated by mul... The static modeling and dynamic simulation are essential and critical processes in petroleum exploration and development. In this study, lithofacies models for Wabiskaw Member in Athabasca, Canada are generated by multipoint statistics(MPS) and then compared with the models built by sequential indicator simulation(SIS). Three training images(Tls) are selected from modern depositional environments;the Orinoco River Delta estuary, Cobequid bay-Salmon River estuary, and Danube River delta environment. In order to validate lithofacies models, average and variance of similarity in lithofacies are calculated through random and zonal blind-well tests.In random six-blind-well test, similarity average of MPS models is higher than that of SIS model. The Salmon MPS model closely resembles facies pattern of Wabiskaw Member in subsurface. Zonal blind-well tests show that successful lithofacies modeling for transitional depositional setting requires additional or proper zonation information on horizontal variation, vertical proportion, and secondary data.As Wabiskaw Member is frontier oilsands lease, it is impossible to evaluate the economics from production data or dynamic simulation. In this study, a dynamic steam assisted gravity drainage(SAGD)performance indicator(SPIDER) on the basis of reservoir characteristics is calculated to build 3 D reservoir model for the evaluation of the SAGD feasibility in Wabiskaw Member. SPIDER depends on reservoir properties, economic limit of steam-oil ratio, and bitumen price. Reservoir properties like porosity,permeability, and water saturation are measured from 13 cores and calculated from 201 well-logs. Three dimensional volumes of reservoir properties are constructed mostly based on relationships among properties. Finally, net present value(NPV) volume can be built by equation relating NPV and SPIDER. The economic area exceeding criterion of US$ 10,000 is identified, and the ranges of reservoir properties are estimated. NPV-volume-generation workflow from reservoir parameter to static model provides costand time-effective method to evaluate the oilsands SAGD project. 展开更多
关键词 Oilsands Multipoint STATISTICS (MPS) Reservoir static modeling economic evaluation Net present value (NPV) SAGD and SPIDER
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Health economic evaluation on population-based Helicobacter pylori eradication and endoscopic screening for gastric cancer prevention 被引量:2
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作者 Zhiqiang Hu Zongchao Liu +2 位作者 Wenqing Li Weicheng You Kaifeng Pan 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2023年第6期595-605,共11页
Gastric cancer is a global public health burden, nearly one million new cases are diagnosed per year worldwide, of which 44% of cases occur in China. The prognosis of gastric cancer varies remarkably by the stage of c... Gastric cancer is a global public health burden, nearly one million new cases are diagnosed per year worldwide, of which 44% of cases occur in China. The prognosis of gastric cancer varies remarkably by the stage of cancer, and most of the patients in China are diagnosed at advanced stages, resulting in poor prognoses. Effective strategies to reduce the burden of gastric cancer include primary prevention through testing and treatment of Helicobacter pylori(H. pylori) and secondary prevention by screening and early detection. Although many countries have issued management guidelines and consensus reports concerning these strategies, the limited availability of healthcare resources often precludes their widespread implementation. Therefore, assessing the costs, benefits, and harms of population-based intervention measures through health economic evaluation is necessary for informed health policy decisions. Accordingly, we synthesize management approaches from different countries on H. pylori eradication and endoscopic screening, and also summarize recent advancements in health economic evaluations on population-based preventive strategies. The goal of the review is to provide empirical evidence supporting optimal resource allocation, maximizing benefits for the population, and ultimately reducing the burden of gastric cancer. 展开更多
关键词 Gastric cancer endoscopic screening Helicobacter pylori health economic evaluation
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Practice and Exploration of Economic Benefit Evaluation of Medical Equipment in Our Hospital 被引量:1
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作者 Wei-wei Shi 《中国医疗设备》 2016年第12期1-3,16,共4页
Objective The evaluation index of medical equipment's economic benefit is based on the usage of medical equipment,the traditional data collection method is time-consuming,laborious and not entirely accurate.The us... Objective The evaluation index of medical equipment's economic benefit is based on the usage of medical equipment,the traditional data collection method is time-consuming,laborious and not entirely accurate.The usage of medical equipment is obtained by designing data query statements from the HIS system.Methods First the charging items are in correspondence with the device's name included,second fees and other relevant data are extracted from charging module in HIS.Through a rough estimate of the recovery period and an increase or decrease ratio,the economic benefit of the medical equipment can be analyzed.Results Through the method of the benefit analysis of the medical equipment,we can clearly find out the different economic benefit of the equipment,and finally analyze the reasons.Conclusion Practice has proved that,this methad,it can greatly reduce human,material resources required in data collection and improve the accuracy of the data.It can help hospital managers timely to grasp the operating costs of medical equipment and other information,and also provide scientific data for hospital managers when they purchase reasonable medical equipment. 展开更多
关键词 economic BENEFIT analysis of medical equipment HOSPITAL information system data QUERY CHARGING items program design
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