A tool for calculating the economic and environmental impacts of the use of byproducts of industrial processes that can substitute for perishable resources was presented.This was exemplified by fly ash(the fine fracti...A tool for calculating the economic and environmental impacts of the use of byproducts of industrial processes that can substitute for perishable resources was presented.This was exemplified by fly ash(the fine fraction of ash originating from coal burned to generate electricity and collected by filtering exhaust gases leaving the furnace),added to soil as a component of sewage sludge stabilized with fly ash and lime(NVS).Application to soil of NVS has potential agricultural and environmental advantages and disadvantages.The costs and benefits of such application were calculated using both a database and expert opinions.The calculations assumed a representative assemblage of soils and crops,with weights assigned to each crop type and soil characteristic.The annual weighted benefits(additional income for the farmer)and costs per hectare reached 324$/ha and 131$/ha respectively.Major potential benefits include:Chemical fertilizer replacement,159$/ha;Improvement to the soil’s physical properties,75$/ha;Supply of vital trace elements,33$/ha.Major potential costs were:Regulatory limitations on marketing of crops pending proof of absence of risk of heavy metals or radionuclides accumulation in these crops,(17$/ha and 36$/ha respectively);Application and incorporation cost,50$/ha.The presented estimates of the costs and benefits refer to the array of soils and conditions typical to Israel.It is possible to maximize potential benefits by applying fly ash only to the most suitable agricultural soils while improper use of fly ash will increase the costs incurred from its use.展开更多
With the introduction of many derivatives into the capital market,including stock index futures,the trading strategies in financial markets have been gradually enriched.However,there is still no theoretical model that...With the introduction of many derivatives into the capital market,including stock index futures,the trading strategies in financial markets have been gradually enriched.However,there is still no theoretical model that can determine whether these strategies are effective,what the risks are,and how costly the strategies are.We built an agent-based cross-market platform that includes five stocks and one stock index future,and constructed an evaluation system for stock index futures trading strategies.The evaluation system includes four dimensions:effectiveness,risk,occupation of capital,and impact cost.The results show that the informed strategy performs well in all aspects.The risk of the technical strategy is relatively higher than that of the other strategies.Moreover,occupation of capital and impact cost are both higher for the arbitrage strategy.Finally,the wealth of noise traders is almost lost.展开更多
The purpose of this study is to explore whether it is worthwhile to launch a routine diabetic retinopathy (DR) screening for blindness pre-vention among Chinese type 2 diabetes from different perspective based on the ...The purpose of this study is to explore whether it is worthwhile to launch a routine diabetic retinopathy (DR) screening for blindness pre-vention among Chinese type 2 diabetes from different perspective based on the popula-tion-based study in Kinmen, Taiwan. A total of 971 community dwelling adults previously di-agnosed with type 2 diabetes in 1991-1993 un-derwent DR screening in 1999-2002 by a panel of ophthalmologists using on-site indirect oph-thalmoscopy and 45-degree color fundus retinal photographs. The cost-benefit analysis is used to evaluate the DR screening. In terms of bene-fit-cost ratio, the different screening programs for DR could save New Taiwan Dollars (NTD) from 14.38 to 36.83 in discounted costs for each dollar incurred in different screening years from the societal viewpoint for Taiwan and save NTD from 0.81 to 1.80 in different screening years from health care payer’s perspective. The av-erage estimate of willingness-to-pay to translate into benefit yields NTD from 937.8 to 4,689 be- nefits per case due to DR screening in different screening years during 10-year follow-up. The net present value of the DR screening were NTD from -167,318 to -307,251.2 in different screening years. In conclusion, it is worthwhile to initial a routine DR screening of Chinese type 2 diabetes for blindness prevention from the societal per-spective but not from consumer decision based on the willingness-to-pay perspective.展开更多
Over 50 years ago, banana export plantations in Panama were ruined by Fusarium wilt race 1 (Foc. R1) since the popular cultivar Gros Michel is susceptible to Foc. R1 [1]. Fortunately, the resistant cultivar Cavendish ...Over 50 years ago, banana export plantations in Panama were ruined by Fusarium wilt race 1 (Foc. R1) since the popular cultivar Gros Michel is susceptible to Foc. R1 [1]. Fortunately, the resistant cultivar Cavendish replaced Gros Michel as the world biggest commercial fruit after ten years’ research and development. Due to its good economic profit, banana industry develops very fast recently in China. Unfortunately, Fusarium oxysporum f. sp. cubense tropical race 4 (TR4) brought disaster to Cavendish plantation since 1996. Most of traditional banana planting zones of Guangdong and Hainan provinces were infected by Foc. TR4 to the end of 2009. In order to fight against Foc. TR4, here we tried to investigate the cost-benefit and disease resistance of six banana cultivars (Cavendish Baxijiao, Dajiao, Guangfen No. 1, Fenzha No. 1, Gongjiao, Haigongjiao) planted in China Foc. Zones. Comparisons were conducted on their economic characteristics, cost, benefit, as well as the advantage and disadvantage and their application in rota-tion. Generally, supposing the investment of $ 4400/ha, the banana plantation attains a good economic profit as $ 2200/ha. Rotation of these cultivars can maintain the biodiversity as well as improve the sustainable development of banana industry.展开更多
Ecological and environmental issues have always been the focus of government work. The economic losses caused by air pollution,water pollution,noise pollution and solid waste pollution caused by land use development p...Ecological and environmental issues have always been the focus of government work. The economic losses caused by air pollution,water pollution,noise pollution and solid waste pollution caused by land use development projects are estimated,and the total population economic losses are incorporated into project costing. Using the analytic hierarchy process,four benefit indicators and five cost indicators are selected for constructing a fuzzy comprehensive evaluation model to evaluate the cost-benefit of projects of different scales. The projects of different scales are ranked according to the level of comprehensive scores. The results show that large-scale projects are cost-effective and stable over the long term,and there are differences in the main sources of pollution-caused economic losses for projects of different scales. At last,reasonable policy suggestions are made to relevant planning and management personnel.展开更多
On the basis of market demand survey of chestnut,this article carries out cost-benefit analysis of the chestnut production in Xingtai County,to understand the profitability and payback period of local chestnut product...On the basis of market demand survey of chestnut,this article carries out cost-benefit analysis of the chestnut production in Xingtai County,to understand the profitability and payback period of local chestnut production.It points out that chestnut production has a high rate of return on investment,and chestnut can be promoted on a large scale in Xingtai County.However,there are still some problems in the production and marketing of chestnut in Xingtai County,such as low level of technology,extensive management,low level of organization,market imperfections and weak brand consciousness.Based on these problems,corresponding recommendations are put forth.展开更多
According to the relevant statistical data in National Agricultural cost-benefit Data Compilation(2001- 2013),we use the modified entropy weight- TOPSIS model to research the cost-benefit status of scale pig breeding ...According to the relevant statistical data in National Agricultural cost-benefit Data Compilation(2001- 2013),we use the modified entropy weight- TOPSIS model to research the cost-benefit status of scale pig breeding in Shandong Province from the perspective of comparing it with that of the entire country and 9 other main pig producing areas. The results show that compared with the national average,the cost-benefit ratio of small scale pig breeding in Shandong Province is lower,while the cost-benefit ratio of medium scale and large scale pig breeding is significantly improved; the cost-benefit ratio of small scale pig breeding in Shandong Province is basically the same as that in 9 other main pig producing areas,while the cost-benefit ratio of medium scale and large scale pig breeding is higher; the output value of main products and the purchase price of piglet are two major bottlenecks restricting the cost-benefit improvement of scale pig breeding in Shandong Province.展开更多
With the rapid economic development of China,the environmental degradation brought by economic development cannot be ignored.In order to measure the cost of environmental degradation brought by land projects in the pr...With the rapid economic development of China,the environmental degradation brought by economic development cannot be ignored.In order to measure the cost of environmental degradation brought by land projects in the process of economic development and evaluate a land project,this paper establishes an ecological service evaluation model based on cost-benefit method to analyze the cost and benefit of land development projects from a new perspective,and explore effective strategies to alleviate environmental degradation.展开更多
Motor vehicle inspection and maintenance (I/M) programs are designed to identify high-emitting vehicles and mitigate their impacts on air quality and climate. I/M programs have been traditionally ranked superior among...Motor vehicle inspection and maintenance (I/M) programs are designed to identify high-emitting vehicles and mitigate their impacts on air quality and climate. I/M programs have been traditionally ranked superior among various vehicle emission control measures by the results of cost-benefit analysis, based on the assumption that these programs will achieve the targeted emission reduction outcomes. However, the actual effects of I/M programs may be greatly uncertain and when this uncertainty is taken into account, these programs may become suboptimal. This study develops a new a cost-benefit analysis framework that links various program design consideration, such as program participation rate, identification rate and effective repair rate, to the public health benefits as well as costs of the programs. This framework helps decision makers to investigate minimum implementation requirements that at least ensure the benefits are greater than the costs of implementing the programs in order to improve the overall effectiveness of the I/M programs. To illustrate the applications of the framework, it was applied to a particulate matter oriented I/M program targeting all diesel-fueled vehicles in the city of Bangkok, Thailand, a large metropolitan area that has been suffering from severe ambient PM pollution mainly attributable to its wide use of diesel-fueled vehicles and motorcycles. It was found that the health benefits achieved from the program are sensitive to several key program design elements, including participation rate and problem vehicle identification rate, fraction of effective repairs and illegal operation rate. Other variables, such as the testing cut-points and vehicle population growth rate, only have modest effects on the overall emission reduction and consequent health benefits. Overall, the performance of multiple variables associated with I/M program design needs to be improved simultaneous in order to achieve the targeted benefits of the program.展开更多
AIM:To estimate the cost-benefit of endoscopic screening strategies of esophageal cancer(EC)in high-risk areas of China. METHODS:Markov model-based analyses were conducted to compare the net present values(NPVs)and th...AIM:To estimate the cost-benefit of endoscopic screening strategies of esophageal cancer(EC)in high-risk areas of China. METHODS:Markov model-based analyses were conducted to compare the net present values(NPVs)and the benefit-cost ratios(BCRs)of 12 EC endoscopic screening strategies.Strategies varied according to the targeted screening age,screening frequencies,and follow-up intervals.Model parameters were collected from population-based studies in China,published literatures,and surveillance data. RESULTS:Compared with non-screening outcomes,all strategies with hypothetical 100 000 subjects saved life years.Among five dominant strategies determined by the incremental cost-effectiveness analysis,screening once at age 50 years incurred the lowest NPV(international dollar-I$55 million)and BCR(2.52).Screening six times between 40-70 years at a 5-year interval[i.e., six times(40)f-strategy]yielded the highest NPV(I$99 million)and BCR(3.06).Compared with six times(40)fstrategy,screening thrice between 40-70 years at a 10-year interval resulted in relatively lower NPV,but the same BCR. CONCLUSION:EC endoscopic screening is cost-beneficial in high-risk areas of China.Policy-makers should consider the cost-benefit,population acceptance,and local economic status when choosing suitable screening strategies.展开更多
Evaluation of the economic costs and benefits of flood disaster risk management projects is crucial.However,current costbenefit analyses(CBA) often lack reliable estimates of the expected loss reduction from flood con...Evaluation of the economic costs and benefits of flood disaster risk management projects is crucial.However,current costbenefit analyses(CBA) often lack reliable estimates of the expected loss reduction from flood control measures and ignore quantitative assessments of resettlement.To address these limitations,this study incorporated a probabilistic risk analysis method and quantitative resettlement benefits assessment into the CBA framework,using the Wuxikou Integrated Flood Management Project(WIFMP) in Jiangxi Province,China,as a case study.The direct economic benefits of flood control were estimated by integrating hydrological statistics,numerical flood inundation simulation,and quantitative damage analysis with exposure and vulnerability data.Furthermore,the resettlement benefits were quantified by measuring the annual income growth of migrants based on assumptions about household employment.Our analysis shows that the total WIFMP investment is RMB 3546.1 million yuan(USD 1=RMB 6.976 yuan),including loan principal and interest of 244.4 million yuan,and operations and maintenance of 605.5 million yuan at 2020 prices.Annual project benefits are estimated at 351.3 million yuan in flood risk reduction,155.7-191.9 million yuan from increased resettlement income,and 42.7 million yuan in power and water revenues.Considering the costs and benefits across the entire project lifecycle,the internal rate of return ranges from 13.7 to 14.2%,and the net present value ranges from 31.8 to 352.6 billion yuan.Through improved benefit estimation methodology,this research enables a more reliable and holistic evaluation of costs and benefits for flood risk management projects.It provides insights for policymakers and practitioners involved in similar projects,contributing to more informed decision making and better allocation of resources in flood disaster risk management.展开更多
A smart wheelchair provides mobility assistance to persons with motor disabilities by processing sensory inputs from the person.This involves accurately collecting inputs from the user during various movement activiti...A smart wheelchair provides mobility assistance to persons with motor disabilities by processing sensory inputs from the person.This involves accurately collecting inputs from the user during various movement activities and using them to determine their intended motion.These smart wheelchairs work by collecting brain signals in the form of electroencephalography(EEG)signals and by processing them into a quantized format to provide movement assistance to people.Such systems can be referred to as brain-computer interface(BCI)systems that work with EEG signals.Acquiring data from human beings in the form of brain signals through EEG,along with processing of those signals and ensuring the correctness of actions instigated by those brain signals involve a huge amount of data.In this work,we carried out an experiment by taking 100 human subjects and recording their brain signals using a NeuroMax device.Typical wheelchairs are constrained by design as the motion of those is limited either by manual operation or controlled by haptic sensors and actuators.The main objective in this work was to design a wheelchair with better usability and control using machine learning-based knowledge,which is typically a data-driven approach.However,the proposed approach was designed to take inputs from human gestures and brain sensory activities to provide better usability to the wheelchair.The attention meditation cost–benefit analysis(AMCBA)proposed in this paper aims to reduce the risk of inappropriate results and improve performance by considering various cost-benefit parameters.The said classifier aims to improve the quality of emotion recognition by filtering features from EEG signals using methods of feature selection.The operation of the proposed method is described in two steps:in the first step,we assign weights to different channels for the extraction of spatial and temporal information from human behavior.The second step presents the cost-benefit model to improve the accuracy to help in decision-making.Moreover,we tried to assess the performance of the wheelchair for various assumptions and technical specifications.Finally,this study achieves improved performance in the most difficult circumstances to provide a better experience to persons with immobility.展开更多
Spatial heterogeneity or“patchiness”of plankton distributions in the ocean has always been an attractive and challenging scientific issue to oceanographers.We focused on the accumulation and dynamic mechanism of the...Spatial heterogeneity or“patchiness”of plankton distributions in the ocean has always been an attractive and challenging scientific issue to oceanographers.We focused on the accumulation and dynamic mechanism of the Acetes chinensis in the Lianyungang nearshore licensed fishing area.The Lagrangian frame approaches including the Lagrangian coherent structures theory,Lagrangian residual current,and Lagrangian particle-tracking model were applied to find the transport pathways and aggregation characteristics of Acetes chinensis.There exist some material transport pathways for Acetes chinensis passing through the licensed fishing area,and Acetes chinensis is easy to accumulate in the licensed fishing area.The main mechanism forming this distribution pattern is the local circulation induced by the nonlinear interaction of topography and tidal flow.Both the Lagrangian coherent structure analysis and the particle trajectory tracking indicate that Acetes chinensis in the licensed fishing area come from the nearshore estuary.This work contributed to the adjustment of licensed fishing area and the efficient utilization of fishery resources.展开更多
Joint time–frequency analysis is an emerging method for interpreting the underlying physics in fuel cells,batteries,and supercapacitors.To increase the reliability of time–frequency analysis,a theoretical correlatio...Joint time–frequency analysis is an emerging method for interpreting the underlying physics in fuel cells,batteries,and supercapacitors.To increase the reliability of time–frequency analysis,a theoretical correlation between frequency-domain stationary analysis and time-domain transient analysis is urgently required.The present work formularizes a thorough model reduction of fractional impedance spectra for electrochemical energy devices involving not only the model reduction from fractional-order models to integer-order models and from high-to low-order RC circuits but also insight into the evolution of the characteristic time constants during the whole reduction process.The following work has been carried out:(i)the model-reduction theory is addressed for typical Warburg elements and RC circuits based on the continued fraction expansion theory and the response error minimization technique,respectively;(ii)the order effect on the model reduction of typical Warburg elements is quantitatively evaluated by time–frequency analysis;(iii)the results of time–frequency analysis are confirmed to be useful to determine the reduction order in terms of the kinetic information needed to be captured;and(iv)the results of time–frequency analysis are validated for the model reduction of fractional impedance spectra for lithium-ion batteries,supercapacitors,and solid oxide fuel cells.In turn,the numerical validation has demonstrated the powerful function of the joint time–frequency analysis.The thorough model reduction of fractional impedance spectra addressed in the present work not only clarifies the relationship between time-domain transient analysis and frequency-domain stationary analysis but also enhances the reliability of the joint time–frequency analysis for electrochemical energy devices.展开更多
Gears are pivotal in mechanical drives,and gear contact analysis is a typically difficult problem to solve.Emerging isogeometric analysis(IGA)methods have developed new ideas to solve this problem.In this paper,a thre...Gears are pivotal in mechanical drives,and gear contact analysis is a typically difficult problem to solve.Emerging isogeometric analysis(IGA)methods have developed new ideas to solve this problem.In this paper,a threedimensional body parametric gear model of IGA is established,and a theoretical formula is derived to realize single-tooth contact analysis.Results were benchmarked against those obtained from commercial software utilizing the finite element analysis(FEA)method to validate the accuracy of our approach.Our findings indicate that the IGA-based contact algorithmsuccessfullymet theHertz contact test.When juxtaposed with the FEA approach,the IGAmethod demonstrated fewer node degrees of freedomand reduced computational units,all whilemaintaining comparable accuracy.Notably,the IGA method appeared to exhibit consistency in analysis accuracy irrespective of computational unit density,and also significantlymitigated non-physical oscillations in contact stress across the tooth width.This underscores the prowess of IGA in contact analysis.In conclusion,IGA emerges as a potent tool for addressing contact analysis challenges and holds significant promise for 3D gear modeling,simulation,and optimization of various mechanical components.展开更多
The supercritical CO_(2)cOoled Lithium-Lead(COOL)blanket has been designed as one advanced blanket candidate for the Chinese Fusion Engineering Test Reactor(CFETR).This work focuses on the electromagnetic(EM)loads(Max...The supercritical CO_(2)cOoled Lithium-Lead(COOL)blanket has been designed as one advanced blanket candidate for the Chinese Fusion Engineering Test Reactor(CFETR).This work focuses on the electromagnetic(EM)loads(Maxwell force and Lorentz force)acting on the COOL blanket,which are important mechanical loads in further structural analysis of the COOL blanket.A 3D electromagnetic analysis is performed using the ANSYS finite element method to obtain EM loads on the COOL blanket in this study.At first,the magnetic scalar potential(MSP)method is used to obtain the magnetic field and the Maxwell force on the COOL blanket.Then,the magnetic vector potential(MVP)method is performed during a plasma disruption event to get the eddy current distribution.At last,a multi-step method is adopted for the calculation of the Lorentz force and the torque.The maximum Lorentz forces of inboard and outboard blanket structural components are 5624 kN and 2360 kN respectively.展开更多
Algal blooms,the spread of algae on the surface of water bodies,have adverse effects not only on aquatic ecosystems but also on human life.The adverse effects of harmful algal blooms(HABs)necessitate a convenient solu...Algal blooms,the spread of algae on the surface of water bodies,have adverse effects not only on aquatic ecosystems but also on human life.The adverse effects of harmful algal blooms(HABs)necessitate a convenient solution for detection and monitoring.Unmanned aerial vehicles(UAVs)have recently emerged as a tool for algal bloom detection,efficiently providing on-demand images at high spatiotemporal resolutions.This study developed an image processing method for algal bloom area estimation from the aerial images(obtained from the internet)captured using UAVs.As a remote sensing method of HAB detection,analysis,and monitoring,a combination of histogram and texture analyses was used to efficiently estimate the area of HABs.Statistical features like entropy(using the Kullback-Leibler method)were emphasized with the aid of a gray-level co-occurrence matrix.The results showed that the orthogonal images demonstrated fewer errors,and the morphological filter best detected algal blooms in real time,with a precision of 80%.This study provided efficient image processing approaches using on-board UAVs for HAB monitoring.展开更多
基金This work was funded by the Israel National Coal Ash Board(INCAB)Grant#39477.The authors wish to express their deep gratitude to the late Mr.Omri Lulav,Head of the INCAB.
文摘A tool for calculating the economic and environmental impacts of the use of byproducts of industrial processes that can substitute for perishable resources was presented.This was exemplified by fly ash(the fine fraction of ash originating from coal burned to generate electricity and collected by filtering exhaust gases leaving the furnace),added to soil as a component of sewage sludge stabilized with fly ash and lime(NVS).Application to soil of NVS has potential agricultural and environmental advantages and disadvantages.The costs and benefits of such application were calculated using both a database and expert opinions.The calculations assumed a representative assemblage of soils and crops,with weights assigned to each crop type and soil characteristic.The annual weighted benefits(additional income for the farmer)and costs per hectare reached 324$/ha and 131$/ha respectively.Major potential benefits include:Chemical fertilizer replacement,159$/ha;Improvement to the soil’s physical properties,75$/ha;Supply of vital trace elements,33$/ha.Major potential costs were:Regulatory limitations on marketing of crops pending proof of absence of risk of heavy metals or radionuclides accumulation in these crops,(17$/ha and 36$/ha respectively);Application and incorporation cost,50$/ha.The presented estimates of the costs and benefits refer to the array of soils and conditions typical to Israel.It is possible to maximize potential benefits by applying fly ash only to the most suitable agricultural soils while improper use of fly ash will increase the costs incurred from its use.
基金The work was supported by the National Nature Science Foundation of China(71532009,71320107003,71271145)Core Projects in Tianjin Education Bureaus Social Science Program(2014ZD13)Tianjin Development Program for Innovation and Entrepreneurship.
文摘With the introduction of many derivatives into the capital market,including stock index futures,the trading strategies in financial markets have been gradually enriched.However,there is still no theoretical model that can determine whether these strategies are effective,what the risks are,and how costly the strategies are.We built an agent-based cross-market platform that includes five stocks and one stock index future,and constructed an evaluation system for stock index futures trading strategies.The evaluation system includes four dimensions:effectiveness,risk,occupation of capital,and impact cost.The results show that the informed strategy performs well in all aspects.The risk of the technical strategy is relatively higher than that of the other strategies.Moreover,occupation of capital and impact cost are both higher for the arbitrage strategy.Finally,the wealth of noise traders is almost lost.
文摘The purpose of this study is to explore whether it is worthwhile to launch a routine diabetic retinopathy (DR) screening for blindness pre-vention among Chinese type 2 diabetes from different perspective based on the popula-tion-based study in Kinmen, Taiwan. A total of 971 community dwelling adults previously di-agnosed with type 2 diabetes in 1991-1993 un-derwent DR screening in 1999-2002 by a panel of ophthalmologists using on-site indirect oph-thalmoscopy and 45-degree color fundus retinal photographs. The cost-benefit analysis is used to evaluate the DR screening. In terms of bene-fit-cost ratio, the different screening programs for DR could save New Taiwan Dollars (NTD) from 14.38 to 36.83 in discounted costs for each dollar incurred in different screening years from the societal viewpoint for Taiwan and save NTD from 0.81 to 1.80 in different screening years from health care payer’s perspective. The av-erage estimate of willingness-to-pay to translate into benefit yields NTD from 937.8 to 4,689 be- nefits per case due to DR screening in different screening years during 10-year follow-up. The net present value of the DR screening were NTD from -167,318 to -307,251.2 in different screening years. In conclusion, it is worthwhile to initial a routine DR screening of Chinese type 2 diabetes for blindness prevention from the societal per-spective but not from consumer decision based on the willingness-to-pay perspective.
文摘Over 50 years ago, banana export plantations in Panama were ruined by Fusarium wilt race 1 (Foc. R1) since the popular cultivar Gros Michel is susceptible to Foc. R1 [1]. Fortunately, the resistant cultivar Cavendish replaced Gros Michel as the world biggest commercial fruit after ten years’ research and development. Due to its good economic profit, banana industry develops very fast recently in China. Unfortunately, Fusarium oxysporum f. sp. cubense tropical race 4 (TR4) brought disaster to Cavendish plantation since 1996. Most of traditional banana planting zones of Guangdong and Hainan provinces were infected by Foc. TR4 to the end of 2009. In order to fight against Foc. TR4, here we tried to investigate the cost-benefit and disease resistance of six banana cultivars (Cavendish Baxijiao, Dajiao, Guangfen No. 1, Fenzha No. 1, Gongjiao, Haigongjiao) planted in China Foc. Zones. Comparisons were conducted on their economic characteristics, cost, benefit, as well as the advantage and disadvantage and their application in rota-tion. Generally, supposing the investment of $ 4400/ha, the banana plantation attains a good economic profit as $ 2200/ha. Rotation of these cultivars can maintain the biodiversity as well as improve the sustainable development of banana industry.
基金Supported by National Natural Science Foundation of China(11601001)Scientific Research Innovation Fund of Anhui University of Finance & Economics(XSKY1957)
文摘Ecological and environmental issues have always been the focus of government work. The economic losses caused by air pollution,water pollution,noise pollution and solid waste pollution caused by land use development projects are estimated,and the total population economic losses are incorporated into project costing. Using the analytic hierarchy process,four benefit indicators and five cost indicators are selected for constructing a fuzzy comprehensive evaluation model to evaluate the cost-benefit of projects of different scales. The projects of different scales are ranked according to the level of comprehensive scores. The results show that large-scale projects are cost-effective and stable over the long term,and there are differences in the main sources of pollution-caused economic losses for projects of different scales. At last,reasonable policy suggestions are made to relevant planning and management personnel.
文摘On the basis of market demand survey of chestnut,this article carries out cost-benefit analysis of the chestnut production in Xingtai County,to understand the profitability and payback period of local chestnut production.It points out that chestnut production has a high rate of return on investment,and chestnut can be promoted on a large scale in Xingtai County.However,there are still some problems in the production and marketing of chestnut in Xingtai County,such as low level of technology,extensive management,low level of organization,market imperfections and weak brand consciousness.Based on these problems,corresponding recommendations are put forth.
基金Supported by Pig Industry Innovation Team Building Program of Modern Agricultural Industrial Technology System in Shandong Province(SDAIT-06-011-10)"Issues concerning Agriculture,Farmers and Countryside"Soft Science Base Project in Shandong Province
文摘According to the relevant statistical data in National Agricultural cost-benefit Data Compilation(2001- 2013),we use the modified entropy weight- TOPSIS model to research the cost-benefit status of scale pig breeding in Shandong Province from the perspective of comparing it with that of the entire country and 9 other main pig producing areas. The results show that compared with the national average,the cost-benefit ratio of small scale pig breeding in Shandong Province is lower,while the cost-benefit ratio of medium scale and large scale pig breeding is significantly improved; the cost-benefit ratio of small scale pig breeding in Shandong Province is basically the same as that in 9 other main pig producing areas,while the cost-benefit ratio of medium scale and large scale pig breeding is higher; the output value of main products and the purchase price of piglet are two major bottlenecks restricting the cost-benefit improvement of scale pig breeding in Shandong Province.
基金Supported by the Project of National Natural Science Foundation "3-stream Conjecture,Fulkerson-coverage and Related Issues"(11601001)
文摘With the rapid economic development of China,the environmental degradation brought by economic development cannot be ignored.In order to measure the cost of environmental degradation brought by land projects in the process of economic development and evaluate a land project,this paper establishes an ecological service evaluation model based on cost-benefit method to analyze the cost and benefit of land development projects from a new perspective,and explore effective strategies to alleviate environmental degradation.
文摘Motor vehicle inspection and maintenance (I/M) programs are designed to identify high-emitting vehicles and mitigate their impacts on air quality and climate. I/M programs have been traditionally ranked superior among various vehicle emission control measures by the results of cost-benefit analysis, based on the assumption that these programs will achieve the targeted emission reduction outcomes. However, the actual effects of I/M programs may be greatly uncertain and when this uncertainty is taken into account, these programs may become suboptimal. This study develops a new a cost-benefit analysis framework that links various program design consideration, such as program participation rate, identification rate and effective repair rate, to the public health benefits as well as costs of the programs. This framework helps decision makers to investigate minimum implementation requirements that at least ensure the benefits are greater than the costs of implementing the programs in order to improve the overall effectiveness of the I/M programs. To illustrate the applications of the framework, it was applied to a particulate matter oriented I/M program targeting all diesel-fueled vehicles in the city of Bangkok, Thailand, a large metropolitan area that has been suffering from severe ambient PM pollution mainly attributable to its wide use of diesel-fueled vehicles and motorcycles. It was found that the health benefits achieved from the program are sensitive to several key program design elements, including participation rate and problem vehicle identification rate, fraction of effective repairs and illegal operation rate. Other variables, such as the testing cut-points and vehicle population growth rate, only have modest effects on the overall emission reduction and consequent health benefits. Overall, the performance of multiple variables associated with I/M program design needs to be improved simultaneous in order to achieve the targeted benefits of the program.
基金Supported by The National Science and Technology Pillar Program of the 11th National Five-Year Plan of China,No. 2006BAI02A15
文摘AIM:To estimate the cost-benefit of endoscopic screening strategies of esophageal cancer(EC)in high-risk areas of China. METHODS:Markov model-based analyses were conducted to compare the net present values(NPVs)and the benefit-cost ratios(BCRs)of 12 EC endoscopic screening strategies.Strategies varied according to the targeted screening age,screening frequencies,and follow-up intervals.Model parameters were collected from population-based studies in China,published literatures,and surveillance data. RESULTS:Compared with non-screening outcomes,all strategies with hypothetical 100 000 subjects saved life years.Among five dominant strategies determined by the incremental cost-effectiveness analysis,screening once at age 50 years incurred the lowest NPV(international dollar-I$55 million)and BCR(2.52).Screening six times between 40-70 years at a 5-year interval[i.e., six times(40)f-strategy]yielded the highest NPV(I$99 million)and BCR(3.06).Compared with six times(40)fstrategy,screening thrice between 40-70 years at a 10-year interval resulted in relatively lower NPV,but the same BCR. CONCLUSION:EC endoscopic screening is cost-beneficial in high-risk areas of China.Policy-makers should consider the cost-benefit,population acceptance,and local economic status when choosing suitable screening strategies.
基金funded by the National Key Research and Development Program of China(Grant No.2022YFC3006404-02).
文摘Evaluation of the economic costs and benefits of flood disaster risk management projects is crucial.However,current costbenefit analyses(CBA) often lack reliable estimates of the expected loss reduction from flood control measures and ignore quantitative assessments of resettlement.To address these limitations,this study incorporated a probabilistic risk analysis method and quantitative resettlement benefits assessment into the CBA framework,using the Wuxikou Integrated Flood Management Project(WIFMP) in Jiangxi Province,China,as a case study.The direct economic benefits of flood control were estimated by integrating hydrological statistics,numerical flood inundation simulation,and quantitative damage analysis with exposure and vulnerability data.Furthermore,the resettlement benefits were quantified by measuring the annual income growth of migrants based on assumptions about household employment.Our analysis shows that the total WIFMP investment is RMB 3546.1 million yuan(USD 1=RMB 6.976 yuan),including loan principal and interest of 244.4 million yuan,and operations and maintenance of 605.5 million yuan at 2020 prices.Annual project benefits are estimated at 351.3 million yuan in flood risk reduction,155.7-191.9 million yuan from increased resettlement income,and 42.7 million yuan in power and water revenues.Considering the costs and benefits across the entire project lifecycle,the internal rate of return ranges from 13.7 to 14.2%,and the net present value ranges from 31.8 to 352.6 billion yuan.Through improved benefit estimation methodology,this research enables a more reliable and holistic evaluation of costs and benefits for flood risk management projects.It provides insights for policymakers and practitioners involved in similar projects,contributing to more informed decision making and better allocation of resources in flood disaster risk management.
文摘A smart wheelchair provides mobility assistance to persons with motor disabilities by processing sensory inputs from the person.This involves accurately collecting inputs from the user during various movement activities and using them to determine their intended motion.These smart wheelchairs work by collecting brain signals in the form of electroencephalography(EEG)signals and by processing them into a quantized format to provide movement assistance to people.Such systems can be referred to as brain-computer interface(BCI)systems that work with EEG signals.Acquiring data from human beings in the form of brain signals through EEG,along with processing of those signals and ensuring the correctness of actions instigated by those brain signals involve a huge amount of data.In this work,we carried out an experiment by taking 100 human subjects and recording their brain signals using a NeuroMax device.Typical wheelchairs are constrained by design as the motion of those is limited either by manual operation or controlled by haptic sensors and actuators.The main objective in this work was to design a wheelchair with better usability and control using machine learning-based knowledge,which is typically a data-driven approach.However,the proposed approach was designed to take inputs from human gestures and brain sensory activities to provide better usability to the wheelchair.The attention meditation cost–benefit analysis(AMCBA)proposed in this paper aims to reduce the risk of inappropriate results and improve performance by considering various cost-benefit parameters.The said classifier aims to improve the quality of emotion recognition by filtering features from EEG signals using methods of feature selection.The operation of the proposed method is described in two steps:in the first step,we assign weights to different channels for the extraction of spatial and temporal information from human behavior.The second step presents the cost-benefit model to improve the accuracy to help in decision-making.Moreover,we tried to assess the performance of the wheelchair for various assumptions and technical specifications.Finally,this study achieves improved performance in the most difficult circumstances to provide a better experience to persons with immobility.
基金the National Natural Science Foundation of China(No.31802297)。
文摘Spatial heterogeneity or“patchiness”of plankton distributions in the ocean has always been an attractive and challenging scientific issue to oceanographers.We focused on the accumulation and dynamic mechanism of the Acetes chinensis in the Lianyungang nearshore licensed fishing area.The Lagrangian frame approaches including the Lagrangian coherent structures theory,Lagrangian residual current,and Lagrangian particle-tracking model were applied to find the transport pathways and aggregation characteristics of Acetes chinensis.There exist some material transport pathways for Acetes chinensis passing through the licensed fishing area,and Acetes chinensis is easy to accumulate in the licensed fishing area.The main mechanism forming this distribution pattern is the local circulation induced by the nonlinear interaction of topography and tidal flow.Both the Lagrangian coherent structure analysis and the particle trajectory tracking indicate that Acetes chinensis in the licensed fishing area come from the nearshore estuary.This work contributed to the adjustment of licensed fishing area and the efficient utilization of fishery resources.
基金support from the National Science Foundation of China(22078190)the National Key R&D Plan of China(2020YFB1505802).
文摘Joint time–frequency analysis is an emerging method for interpreting the underlying physics in fuel cells,batteries,and supercapacitors.To increase the reliability of time–frequency analysis,a theoretical correlation between frequency-domain stationary analysis and time-domain transient analysis is urgently required.The present work formularizes a thorough model reduction of fractional impedance spectra for electrochemical energy devices involving not only the model reduction from fractional-order models to integer-order models and from high-to low-order RC circuits but also insight into the evolution of the characteristic time constants during the whole reduction process.The following work has been carried out:(i)the model-reduction theory is addressed for typical Warburg elements and RC circuits based on the continued fraction expansion theory and the response error minimization technique,respectively;(ii)the order effect on the model reduction of typical Warburg elements is quantitatively evaluated by time–frequency analysis;(iii)the results of time–frequency analysis are confirmed to be useful to determine the reduction order in terms of the kinetic information needed to be captured;and(iv)the results of time–frequency analysis are validated for the model reduction of fractional impedance spectra for lithium-ion batteries,supercapacitors,and solid oxide fuel cells.In turn,the numerical validation has demonstrated the powerful function of the joint time–frequency analysis.The thorough model reduction of fractional impedance spectra addressed in the present work not only clarifies the relationship between time-domain transient analysis and frequency-domain stationary analysis but also enhances the reliability of the joint time–frequency analysis for electrochemical energy devices.
基金support provided by the National Nature Science Foundation of China (Grant Nos.52075340,51875360)Project of Science and Technology Commission of Shanghai Municipality (No.19060502300).
文摘Gears are pivotal in mechanical drives,and gear contact analysis is a typically difficult problem to solve.Emerging isogeometric analysis(IGA)methods have developed new ideas to solve this problem.In this paper,a threedimensional body parametric gear model of IGA is established,and a theoretical formula is derived to realize single-tooth contact analysis.Results were benchmarked against those obtained from commercial software utilizing the finite element analysis(FEA)method to validate the accuracy of our approach.Our findings indicate that the IGA-based contact algorithmsuccessfullymet theHertz contact test.When juxtaposed with the FEA approach,the IGAmethod demonstrated fewer node degrees of freedomand reduced computational units,all whilemaintaining comparable accuracy.Notably,the IGA method appeared to exhibit consistency in analysis accuracy irrespective of computational unit density,and also significantlymitigated non-physical oscillations in contact stress across the tooth width.This underscores the prowess of IGA in contact analysis.In conclusion,IGA emerges as a potent tool for addressing contact analysis challenges and holds significant promise for 3D gear modeling,simulation,and optimization of various mechanical components.
基金supported by the Comprehensive Research Facility for Fusion Technology(CRAFT)Program of China(No.2018-000052-73-01-001228)National Natural Science Foundation of China(No.12205330)。
文摘The supercritical CO_(2)cOoled Lithium-Lead(COOL)blanket has been designed as one advanced blanket candidate for the Chinese Fusion Engineering Test Reactor(CFETR).This work focuses on the electromagnetic(EM)loads(Maxwell force and Lorentz force)acting on the COOL blanket,which are important mechanical loads in further structural analysis of the COOL blanket.A 3D electromagnetic analysis is performed using the ANSYS finite element method to obtain EM loads on the COOL blanket in this study.At first,the magnetic scalar potential(MSP)method is used to obtain the magnetic field and the Maxwell force on the COOL blanket.Then,the magnetic vector potential(MVP)method is performed during a plasma disruption event to get the eddy current distribution.At last,a multi-step method is adopted for the calculation of the Lorentz force and the torque.The maximum Lorentz forces of inboard and outboard blanket structural components are 5624 kN and 2360 kN respectively.
文摘Algal blooms,the spread of algae on the surface of water bodies,have adverse effects not only on aquatic ecosystems but also on human life.The adverse effects of harmful algal blooms(HABs)necessitate a convenient solution for detection and monitoring.Unmanned aerial vehicles(UAVs)have recently emerged as a tool for algal bloom detection,efficiently providing on-demand images at high spatiotemporal resolutions.This study developed an image processing method for algal bloom area estimation from the aerial images(obtained from the internet)captured using UAVs.As a remote sensing method of HAB detection,analysis,and monitoring,a combination of histogram and texture analyses was used to efficiently estimate the area of HABs.Statistical features like entropy(using the Kullback-Leibler method)were emphasized with the aid of a gray-level co-occurrence matrix.The results showed that the orthogonal images demonstrated fewer errors,and the morphological filter best detected algal blooms in real time,with a precision of 80%.This study provided efficient image processing approaches using on-board UAVs for HAB monitoring.