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
Enhancing the economic resilience of agriculture is essential for promoting sustainable and high-quality agricultural development.The emergence of digital technology has created new opportunities in this field.However...Enhancing the economic resilience of agriculture is essential for promoting sustainable and high-quality agricultural development.The emergence of digital technology has created new opportunities in this field.However,existing research predominantly focuses on traditional agricultural factors and technologies.Therefore,the impact of digital technology on agricultural economic resilience within the broader context of the“production-operation-industry”system in agriculture has not been comprehensively explored.To bridge this gap,this study analyzes panel data from 30 Chinese provinces from 2011 to 2020.It employs the static Van Dorn’s law and a dynamic spatial panel model to examine how digital technology empowers agricultural resilience.The findings indicate a continuous strengthening of digital technology development in China,albeit with significant polarization and spatial imbalances.Moreover,the resilience of the agricultural economy undergoes notable fluctuations,initially narrowing and subsequently displaying an upward trend.Digital technology clearly plays a pivotal role in empowering resilience through agricultural scale operation,industrial transformation,and technological progress.Its impact,particularly on the promotion of resilience in the eastern region and non-grain-producing areas and on high-level agricultural economies,also shows regional and technological variations.展开更多
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
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
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
[Objectives]Sugarcane is the most significant sugar cash crop in the tropical and subtropical regions of China.However,it is notable for its narrow genetic basis,limited trait improvement,weak adaptability of varietie...[Objectives]Sugarcane is the most significant sugar cash crop in the tropical and subtropical regions of China.However,it is notable for its narrow genetic basis,limited trait improvement,weak adaptability of varieties,and poor planting efficiency.In order to accelerate the process of sugarcane variety replacement and expand the basis of genetic variation,interspecific hybridization and multiple mutagenesis are the most effective methods for obtaining new sugarcane varieties.The evaluation and identification of phenotypic traits of germplasm represents a significant analytical method.The"Zhongtang"series of sugarcane varieties is distinguished by its high yield and high sugar content.New sugarcane germplasms with excellent agronomic and quality traits can be identified and developed as breeding parents and new breeding lines through comprehensive evaluation of the existing germplasm.[Methods]A total of 181 new lines were selected through genetic origin and orientation,and evaluated and appraised for growth,yield,and economic characteristics.The data on 6 important agronomic and quality traits,including tillering,initial plant height,plant height,stem diameter,number of effective stems,and brix at maturity,were used to discover superior lines.These traits were evaluated during the two production seasons of the participant lines.[Results]A comprehensive evaluation of seedling growth traits and economic traits at maturity of the experimental lines identified 30 excellent new germplasms of sugarcane.Among the selected lines,1501 and 1701 exhibited superior agronomic and quality traits,rendering them suitable as parental lines for sugarcane breeding or breeding as new varieties.[Conclusions]The exemplary results obtained in this study provide a solid foundation for the improvement of sugarcane germplasm,with the goal of enhancing quality and efficiency.These findings are of great scientific and practical significance to the study of sugarcane yield and sugar-related genes,as well as the exploration of the evaluation and utilization of sugarcane germplasm resources.展开更多
In the technical and economic system,there is a certain interaction between various technologies,mainly in the form of technology diffusion.By constructing the mathematical model of technology diffusion,the trend of t...In the technical and economic system,there is a certain interaction between various technologies,mainly in the form of technology diffusion.By constructing the mathematical model of technology diffusion,the trend of technology diffusion can be predicted,the reasonable distribution of science and technology productivity can be realized,and the policy optimization measures can be formulated on the basis of evaluating the existing policies.This paper first points out the basic idea of digital model of technology diffusion,and then focuses on the analysis of various parameters of mathematical model of technology diffusion,and puts forward the application conclusion of mathematical model of technology diffusion,in order to provide reference for relevant industry personnel.展开更多
With the continuous development of China,the requirements for road construction are also increasing.Among them,strengthening the performance of roadbed test can effectively improve road construction.Besides,it is also...With the continuous development of China,the requirements for road construction are also increasing.Among them,strengthening the performance of roadbed test can effectively improve road construction.Besides,it is also crucial to perform suitable tests in a timely manner.Therefore,highway inspection technology should be improved for the continuous development of highway construction,which will be explained in this paper,in hopes of improving the construction of highway in China.展开更多
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
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
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
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
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
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
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
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
This article analyzes the typical enterprise's land use structure,land use efficiency,land use intensity and industrial structure in Ma'anshan Economic and Technological Development Zone. Based on the survey r...This article analyzes the typical enterprise's land use structure,land use efficiency,land use intensity and industrial structure in Ma'anshan Economic and Technological Development Zone. Based on the survey results about the typical enterprises,this article put forth the following recommendations: promoting the economical and intensive land use in the development zone by tapping connotation; enhancing the smart land use in the development zone through optimization of function layout; promoting the industrial chain linkage in the development zone through the establishment of industrial land exit mechanism.展开更多
In recent years,with high-speed development of economy and society,and fast propulsion of industrialization and urbanization process in the development zone,average annual land demand in the development zone also quic...In recent years,with high-speed development of economy and society,and fast propulsion of industrialization and urbanization process in the development zone,average annual land demand in the development zone also quickly enlarges,and the contradiction between high-speed growth of economy and shortage of land resources is apparent increasingly. Meanwhile,to guarantee crop safety and stick to 0. 12 billion hm2of farmland red line as a rigid constraint which could not be exceeded,the supply-demand contradiction of industrial land is more and more prominent. With industrial land scale continues to enlarge,land resources become more and more scarce,but there exists the phenomenon of low-efficiency land use and even idle. For land use characteristics of the development zone,taking Hefei City Economic and Technological Development Zone as an example,the countermeasures of perfecting industrial land transfer mechanism in the development zone are proposed.展开更多
This paper brings together the debate on economic impacts of renewable energy (RE) deployment and the discussion on modelling endogenous technological change on the global markets for the different renewable power gen...This paper brings together the debate on economic impacts of renewable energy (RE) deployment and the discussion on modelling endogenous technological change on the global markets for the different renewable power generation technologies. Economic impacts of RE deployment are still mostly discussed on national level, where different effects have been identified. Recent research for Germany shows positive effects on the macro level and different distributional impacts. High investment in solar photovoltaics (PV) from 2010 to 2012 and induced increases in the RE sur-charge are the main drivers. At the same time, cost reductions for wind and solar PV take place on global markets, with global learning curves explaining the cost reductions very well. This calls for better including the international dimension into the modelling. The complex feedback loops between global cost curves and national policies, which react to global learning with some time lags, are not yet integrated into complex economic models. These models have to capture different RE technologies, different industries, either delivering the RE technologies or strongly depending on electricity prices, which are influenced by national support policies and macroeconomic development. As a first step to better understand the role of international markets, assumptions on RE exports based on global scenarios can be used. Results show the importance of global markets at least for the German RE industries. If the international dimension is taken into account, mainly positive economic impacts of further RE deployment can be observed.展开更多
This study aims to develop an economic evaluation method for installing photovoltaic power generation in ordinary homes using GIS (Geographic Information Systems). The conclusions can be summarized in the following th...This study aims to develop an economic evaluation method for installing photovoltaic power generation in ordinary homes using GIS (Geographic Information Systems). The conclusions can be summarized in the following three points: 1) This method determines the profit and loss and payback period in order to evaluate the installation of photovoltaic power generation, taking into account the price of equipment, solar battery module conversion efficiency, subsidy, electricity purchase price, service life and rate for selling electricity. 2) The proposed evaluation method was applied to Kanagawa Prefecture in Japan, providing plural scenarios. Using a solar battery module conversion efficiency of more than 15%, it is possible to make the payback period shorter than the 20-year service life and anticipate a profit in almost the whole area. 3) The areas suitable for photovoltaic power generation are Kawasaki City and Ninomiya-machi. It is necessary to adopt measures to increase the subsidy and install photovoltaic power generating systems in specific places in areas where subsidies are not provided in enough amounts.展开更多
文摘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.
基金the National Social Science Foundation[Grant No.21&ZD101]:Research on the Implementation Path and Policy System of High-quality Development of China’s Food Industrythe National Social Science Foundation[Grant No.BGL167]:Research on the Green Benefit Sharing Mechanism of Ecological Protection in the Yangtze River Basin(2021-2024)for its support.
文摘Enhancing the economic resilience of agriculture is essential for promoting sustainable and high-quality agricultural development.The emergence of digital technology has created new opportunities in this field.However,existing research predominantly focuses on traditional agricultural factors and technologies.Therefore,the impact of digital technology on agricultural economic resilience within the broader context of the“production-operation-industry”system in agriculture has not been comprehensively explored.To bridge this gap,this study analyzes panel data from 30 Chinese provinces from 2011 to 2020.It employs the static Van Dorn’s law and a dynamic spatial panel model to examine how digital technology empowers agricultural resilience.The findings indicate a continuous strengthening of digital technology development in China,albeit with significant polarization and spatial imbalances.Moreover,the resilience of the agricultural economy undergoes notable fluctuations,initially narrowing and subsequently displaying an upward trend.Digital technology clearly plays a pivotal role in empowering resilience through agricultural scale operation,industrial transformation,and technological progress.Its impact,particularly on the promotion of resilience in the eastern region and non-grain-producing areas and on high-level agricultural economies,also shows regional and technological variations.
基金Supported by Special Research Fund for the Nonprofit Industry of the Ministry of Land and Resources(201111010)
文摘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.
基金supported in part by the Beijing Hospitals Authority Clinical Medicine Development of Special Funding Support (No. ZLRK202325)a grant from National Key R&D Program of China (No. 2018YFC 1313105)。
文摘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.
文摘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.
基金Supported by High-level Talents Project of Basic and Applied Basic Research Program(Natural Science Field)of Hainan Province(320RC715)Earmarked Fund for China Agricultural Research System(CARS-170716).
文摘[Objectives]Sugarcane is the most significant sugar cash crop in the tropical and subtropical regions of China.However,it is notable for its narrow genetic basis,limited trait improvement,weak adaptability of varieties,and poor planting efficiency.In order to accelerate the process of sugarcane variety replacement and expand the basis of genetic variation,interspecific hybridization and multiple mutagenesis are the most effective methods for obtaining new sugarcane varieties.The evaluation and identification of phenotypic traits of germplasm represents a significant analytical method.The"Zhongtang"series of sugarcane varieties is distinguished by its high yield and high sugar content.New sugarcane germplasms with excellent agronomic and quality traits can be identified and developed as breeding parents and new breeding lines through comprehensive evaluation of the existing germplasm.[Methods]A total of 181 new lines were selected through genetic origin and orientation,and evaluated and appraised for growth,yield,and economic characteristics.The data on 6 important agronomic and quality traits,including tillering,initial plant height,plant height,stem diameter,number of effective stems,and brix at maturity,were used to discover superior lines.These traits were evaluated during the two production seasons of the participant lines.[Results]A comprehensive evaluation of seedling growth traits and economic traits at maturity of the experimental lines identified 30 excellent new germplasms of sugarcane.Among the selected lines,1501 and 1701 exhibited superior agronomic and quality traits,rendering them suitable as parental lines for sugarcane breeding or breeding as new varieties.[Conclusions]The exemplary results obtained in this study provide a solid foundation for the improvement of sugarcane germplasm,with the goal of enhancing quality and efficiency.These findings are of great scientific and practical significance to the study of sugarcane yield and sugar-related genes,as well as the exploration of the evaluation and utilization of sugarcane germplasm resources.
文摘In the technical and economic system,there is a certain interaction between various technologies,mainly in the form of technology diffusion.By constructing the mathematical model of technology diffusion,the trend of technology diffusion can be predicted,the reasonable distribution of science and technology productivity can be realized,and the policy optimization measures can be formulated on the basis of evaluating the existing policies.This paper first points out the basic idea of digital model of technology diffusion,and then focuses on the analysis of various parameters of mathematical model of technology diffusion,and puts forward the application conclusion of mathematical model of technology diffusion,in order to provide reference for relevant industry personnel.
文摘With the continuous development of China,the requirements for road construction are also increasing.Among them,strengthening the performance of roadbed test can effectively improve road construction.Besides,it is also crucial to perform suitable tests in a timely manner.Therefore,highway inspection technology should be improved for the continuous development of highway construction,which will be explained in this paper,in hopes of improving the construction of highway in China.
基金funded by the Beijing Natural Science Foundation (9144033)the National Social Science Fund for Major Projects (11&ZD164)
文摘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.
文摘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.
基金Under the auspices of National Natural Science Foundation of China (No. 40771170)Beijing Municipal Natural Science Foundation (No. 8082010)
文摘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.
基金supported by the National Health Commission of the People’s Republic of China (formerly the Health and Family Planning Commission) of China (No. 201502004)
文摘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.
文摘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.
基金supported by the Energy Efficiency and Resources Program of the Korea Institute of Energy Technology Evaluation andPlanning(KETEP,Grant No.20132510100060)the Basic Research Program of Korea Institute of Geoscience and Mineral Resources(KIGAM,GP2017-024)+2 种基金funded by the Ministry of ScienceICTFuture Planning of Korea
文摘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.
文摘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.
文摘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.
文摘This article analyzes the typical enterprise's land use structure,land use efficiency,land use intensity and industrial structure in Ma'anshan Economic and Technological Development Zone. Based on the survey results about the typical enterprises,this article put forth the following recommendations: promoting the economical and intensive land use in the development zone by tapping connotation; enhancing the smart land use in the development zone through optimization of function layout; promoting the industrial chain linkage in the development zone through the establishment of industrial land exit mechanism.
文摘In recent years,with high-speed development of economy and society,and fast propulsion of industrialization and urbanization process in the development zone,average annual land demand in the development zone also quickly enlarges,and the contradiction between high-speed growth of economy and shortage of land resources is apparent increasingly. Meanwhile,to guarantee crop safety and stick to 0. 12 billion hm2of farmland red line as a rigid constraint which could not be exceeded,the supply-demand contradiction of industrial land is more and more prominent. With industrial land scale continues to enlarge,land resources become more and more scarce,but there exists the phenomenon of low-efficiency land use and even idle. For land use characteristics of the development zone,taking Hefei City Economic and Technological Development Zone as an example,the countermeasures of perfecting industrial land transfer mechanism in the development zone are proposed.
文摘This paper brings together the debate on economic impacts of renewable energy (RE) deployment and the discussion on modelling endogenous technological change on the global markets for the different renewable power generation technologies. Economic impacts of RE deployment are still mostly discussed on national level, where different effects have been identified. Recent research for Germany shows positive effects on the macro level and different distributional impacts. High investment in solar photovoltaics (PV) from 2010 to 2012 and induced increases in the RE sur-charge are the main drivers. At the same time, cost reductions for wind and solar PV take place on global markets, with global learning curves explaining the cost reductions very well. This calls for better including the international dimension into the modelling. The complex feedback loops between global cost curves and national policies, which react to global learning with some time lags, are not yet integrated into complex economic models. These models have to capture different RE technologies, different industries, either delivering the RE technologies or strongly depending on electricity prices, which are influenced by national support policies and macroeconomic development. As a first step to better understand the role of international markets, assumptions on RE exports based on global scenarios can be used. Results show the importance of global markets at least for the German RE industries. If the international dimension is taken into account, mainly positive economic impacts of further RE deployment can be observed.
文摘This study aims to develop an economic evaluation method for installing photovoltaic power generation in ordinary homes using GIS (Geographic Information Systems). The conclusions can be summarized in the following three points: 1) This method determines the profit and loss and payback period in order to evaluate the installation of photovoltaic power generation, taking into account the price of equipment, solar battery module conversion efficiency, subsidy, electricity purchase price, service life and rate for selling electricity. 2) The proposed evaluation method was applied to Kanagawa Prefecture in Japan, providing plural scenarios. Using a solar battery module conversion efficiency of more than 15%, it is possible to make the payback period shorter than the 20-year service life and anticipate a profit in almost the whole area. 3) The areas suitable for photovoltaic power generation are Kawasaki City and Ninomiya-machi. It is necessary to adopt measures to increase the subsidy and install photovoltaic power generating systems in specific places in areas where subsidies are not provided in enough amounts.