Statistical distributions are used to model wind speed,and the twoparameters Weibull distribution has proven its effectiveness at characterizing wind speed.Accurate estimation of Weibull parameters,the scale(c)and sha...Statistical distributions are used to model wind speed,and the twoparameters Weibull distribution has proven its effectiveness at characterizing wind speed.Accurate estimation of Weibull parameters,the scale(c)and shape(k),is crucial in describing the actual wind speed data and evaluating the wind energy potential.Therefore,this study compares the most common conventional numerical(CN)estimation methods and the recent intelligent optimization algorithms(IOA)to show how precise estimation of c and k affects the wind energy resource assessments.In addition,this study conducts technical and economic feasibility studies for five sites in the northern part of Saudi Arabia,namely Aljouf,Rafha,Tabuk,Turaif,and Yanbo.Results exhibit that IOAs have better performance in attaining optimal Weibull parameters and provided an adequate description of the observed wind speed data.Also,with six wind turbine technologies rating between 1 and 3MW,the technical and economic assessment results reveal that the CN methods tend to overestimate the energy output and underestimate the cost of energy($/kWh)compared to the assessments by IOAs.The energy cost analyses show that Turaif is the windiest site,with an electricity cost of$0.016906/kWh.The highest wind energy output is obtained with the wind turbine having a rated power of 2.5 MW at all considered sites with electricity costs not exceeding$0.02739/kWh.Finally,the outcomes of this study exhibit the potential of wind energy in Saudi Arabia,and its environmental goals can be acquired by harvesting wind energy.展开更多
The offshore pipeline network in the U.S. Gulf of Mexico is the largest and most transparent system in the world. A review of deepwater projects in the region provides insight into construction cost and installation m...The offshore pipeline network in the U.S. Gulf of Mexico is the largest and most transparent system in the world. A review of deepwater projects in the region provides insight into construction cost and installation methods and the evolution of contract strategies. Pipeline projects are identified as export systems, infield flowline systems, and combined export and infield systems, and three dozen deepwater pipeline installations from 1980–2014 are described based on Offshore Technology Conference(OTC) and Society of Petroleum Engineers(SPE) industry publications and press release data. Export lines and infield flowlines are equally represented and many projects used a combination of J-lay, S-lay and reel methods with rigid steel, flexible line, and pipe-in-pipe systems. The average 2014 inflation-adjusted cost for pipeline projects based on OTC/SPE publications was $2.76 million/mi and ranged from $520 000/mi to $12.94 million/mi. High cost pipelines tend to be short segments or specialized pipeline. Excluding the two cost endpoints, the majority of projects ranged from $1 to $6 million/mi. The average inflation-adjusted cost to install deepwater pipelines in the U.S. Gulf of Mexico based on available public data is estimated at $3.1 million/mi.展开更多
Objective:To develop a rapid,cost effective RT-PCR method for the mass scale diagnosis of such diseases at the vireraia stage to find out the actual disease burden in that area.Methods:For this purpose,cases with the ...Objective:To develop a rapid,cost effective RT-PCR method for the mass scale diagnosis of such diseases at the vireraia stage to find out the actual disease burden in that area.Methods:For this purpose,cases with the history of only short febrile illness were considered.Thus 157 samples with the history of dengue/chikungunya like illness and only 58 samples with a history of acute encephalitis syndrome(AES)were selected.Results:Out of 157 samples,42 and 74 were detected as dengue and chikungunya,respectively and out of 58 AES cases only 23 could be detected as Japanese encephalitis by this RT-PCR method.Conclusions:This cost effective RT-PCR method can detect the total positive cases that remain undetected by EL1SA method.Moreover,this method is capable to detect the viral RNA from patients'sera even after the appearance of IgM antibody at one fifth costs as compared with the other commercially available kits.展开更多
To making the decision of the developing blue prints,ideal point method was selected to estimate the life cycle cost with effectiveness of torpedo.At the same time,the concept of grey relational entropy of the grey sy...To making the decision of the developing blue prints,ideal point method was selected to estimate the life cycle cost with effectiveness of torpedo.At the same time,the concept of grey relational entropy of the grey system theory was adopted to compute the distance between each blue print and the ideal point(or negative ideal point).The blue print,nearest to the ideal point and farthest to the negative ideal point,is the best one.As an example,four blue prints of torpedo were estimated.The result indicates the practical value of this method.展开更多
On the basis of describing the connotation of agricultural intangible asset and cost method,the technical ideas of appraising by cost method are introduced.The article analyzes the advantages(simple appraisal principl...On the basis of describing the connotation of agricultural intangible asset and cost method,the technical ideas of appraising by cost method are introduced.The article analyzes the advantages(simple appraisal principle and easy to understand and grasp;overall consideration of various factors related to appraisal result value) and disadvantages(high appraisal cost;difficult to appraise and grasp various appraisal factors) of appraising by cost method.The article also summarizes the precondition of appraising by cost method:it is applicable to appraise the agricultural intangible asset which can be reproduced and afresh developed.Based on the cognition of agricultural intangible asset and the relevant rules of Ministry of Finance on appraisal of intangible asset by using cost method,the model of appraising agricultural intangible asset by cost method is constructed.That is:agricultural intangible asset value = replacement cost of agricultural intangible asset ×newness rate + opportunity cost of agricultural intangible asset.Determine and analyze parameters of the model,in order to offer references for appraisers to appraise agricultural intangible asset value more reasonably.展开更多
Despite a multitude of theoretical discussions on China's mixed ownership reform, very few studies have addressed realistic questions concerning the implementation of the reform. The Resolutions of the Third Plenu...Despite a multitude of theoretical discussions on China's mixed ownership reform, very few studies have addressed realistic questions concerning the implementation of the reform. The Resolutions of the Third Plenum of the 18 th CPC Central Committee and other reform strategies have outlined the reform of sectors with natural monopoly, including urban public utility sectors. The question is how mixed ownership reform should be carried out in sectors of natural monopoly, or which public utilities sectors should enjoy priority of mixed ownership reform. To answer this question, this paper employs data of large public utility enterprises in China from 1998 to 2008, and estimates the natural monopoly attribute at the industry level and corporate total factor productivity(TFP) using cost function analysis method excluding the impact of product price factor. Based on the difference-indifferences-in-differences(DDD) method of natural experiment, an empirical test is carried out for the relationship among natural monopoly, mixed ownership reform and corporate productivity. Our results suggest that:(1) Statistically, mixed ownership reform cannot significantly increase corporate TFP in sectors with natural monopoly;(2) mixed ownership reform should not be carried out indiscriminately on a nationwide basis and for all public utilities sectors. Such an attempt of reform without distinguishing natural monopoly and the level of competitiveness is fraught with policy uncertainties;(3) relative to sectors with natural monopoly, corporate productivity in competitive sectors after mixed ownership reform will improve more significantly and enjoy greater "policy dividends" of institutional reform. Therefore, mixed ownership reform should be carried out first in competitive sectors.展开更多
The In most contingent valuation (CV) studies, WTP (Willingness to pay) and WTA (Willingness to accept) were often used separately, so protesting or no response or even babbling answers are increasing, and the debate ...The In most contingent valuation (CV) studies, WTP (Willingness to pay) and WTA (Willingness to accept) were often used separately, so protesting or no response or even babbling answers are increasing, and the debate persists over the reliability of CV in economic policy analysis. In order to improve the reliability of CV, WTP and WTA is used syn-chronously to estimate the restoration cost of Maqu grassland ecosystem. Data were partly from questionnaire survey, and partly from interviews and authorities. Before conclusions were derived, we assumed these data that came from interviews and authorities were right. The main result is: If we assumed that the degraded grassland of Maqu needs 10 years to be restored, and divided the restoring period into two stages, then the restoration cost was 0.85 × 108 RMB per year in former 4 years, 0.022 × 108 RMB per year in latter 6 years. The total cost of Maqu grassland restoration was 3.62 × 108 RMB. For all the costs of restoration, WTA occupied 94% and WTP only occupied 6%, suggesting that local grassland degradation was mainly caused by overgrazing and that the overloading livestock must be eliminated in order to achieve restoration successfully. Our research also showed that combining WTP and WTA in contingent valuation is very useful in estimating the cost of environmental improvement projects. Of course, whether these results are right or not, further researches are needed in the future, especially for the actual number of livestock in Maqu grassland.展开更多
Road transport is a flexible mode of transport and its importance in era of globalization increases. Management of road transport companies is, in this turbulent environment, exposed to many technical, legislative, an...Road transport is a flexible mode of transport and its importance in era of globalization increases. Management of road transport companies is, in this turbulent environment, exposed to many technical, legislative, and economic problems. Especially, the growing economic pressure leads to an urgent requirement of the manager and control system improvement. Activity-based costing (ABC) method is a very powerful tool to improve products, services, processes, and market strategies. ABC allows company management to understand what causes costs and how to manage them. Company under this scheme may get a glimpse of how efficiently a company converts the source value. The main objective of our research was to assess the possibility of application of the ABC method in a transport undertaking. ABC method as a fundamentally different view on the cost in the transport business helps to find the reasons of cost and thereby influences their levels to make better use of resources.. New managerial accounting methods aim to show management what information is needed, how and where this information can be obtained, and how they can be useful for the management of the company's proper planning, decision-making, and control. Information provided by management accounting is often a key factor in the analysis of alternative ways of solving problems. This article focuses on the transport enterprise management and helps to decide on the use of this method in business practice.展开更多
For facing the challenges brought by large-scale renewable energy having access to the system and considering the key technologies of energy Internet,it is very necessary to put forward the location method of distribu...For facing the challenges brought by large-scale renewable energy having access to the system and considering the key technologies of energy Internet,it is very necessary to put forward the location method of distribution network equipment and capacity from the perspective of life cycle cost.Compared with the traditional energy network,the equipment capacity problem of energy interconnected distribution network which involves in electricity network,thermal energy network and natural gas network is comprehensively considered in this paper.On this basis,firstly,the operation architecture of energy interconnected distribution network is designed.Secondly,taking the grid connection location and configuration capacity of key equipment in the system as the control variables and the operation cost of system comprehensive planning in the whole life cycle as the goal,the equipment location and capacity optimization model of energy interconnected distribution network is established.Finally,an IEEE 33 bus energy mutual distribution grid system is taken for example analysis,and the improved chaotic particle swarmoptimization algorithm is used to solve it.The simulation results show that the method proposed in this paper is suitable for the equipment location and capacity planning of energy interconnected distribution network,and it can effectively improve the social and economic benefits of system operation.展开更多
At present,with the rapid development of China's economy,the development of the construction industry has made a new breakthrough.Project management requires the construction industry to continuously play its role...At present,with the rapid development of China's economy,the development of the construction industry has made a new breakthrough.Project management requires the construction industry to continuously play its role and value in improving the ability of project management.Earned value method,which is an important way in the field of project management,enables whole project management to rise to a new height.The specific principle of earned value method will be elaborated by fully introducing the specific role of earned value method in engineering projects to provide a reference and basis for practitioners to improve their management ability.展开更多
基金The author extends his appreciation to theDeputyship forResearch&Innovation,Ministry of Education,Saudi Arabia for funding this research work through the Project Number(QUIF-4-3-3-33891)。
文摘Statistical distributions are used to model wind speed,and the twoparameters Weibull distribution has proven its effectiveness at characterizing wind speed.Accurate estimation of Weibull parameters,the scale(c)and shape(k),is crucial in describing the actual wind speed data and evaluating the wind energy potential.Therefore,this study compares the most common conventional numerical(CN)estimation methods and the recent intelligent optimization algorithms(IOA)to show how precise estimation of c and k affects the wind energy resource assessments.In addition,this study conducts technical and economic feasibility studies for five sites in the northern part of Saudi Arabia,namely Aljouf,Rafha,Tabuk,Turaif,and Yanbo.Results exhibit that IOAs have better performance in attaining optimal Weibull parameters and provided an adequate description of the observed wind speed data.Also,with six wind turbine technologies rating between 1 and 3MW,the technical and economic assessment results reveal that the CN methods tend to overestimate the energy output and underestimate the cost of energy($/kWh)compared to the assessments by IOAs.The energy cost analyses show that Turaif is the windiest site,with an electricity cost of$0.016906/kWh.The highest wind energy output is obtained with the wind turbine having a rated power of 2.5 MW at all considered sites with electricity costs not exceeding$0.02739/kWh.Finally,the outcomes of this study exhibit the potential of wind energy in Saudi Arabia,and its environmental goals can be acquired by harvesting wind energy.
基金provided through the U.S. Department of the Interior, Bureau of Ocean Energy Management
文摘The offshore pipeline network in the U.S. Gulf of Mexico is the largest and most transparent system in the world. A review of deepwater projects in the region provides insight into construction cost and installation methods and the evolution of contract strategies. Pipeline projects are identified as export systems, infield flowline systems, and combined export and infield systems, and three dozen deepwater pipeline installations from 1980–2014 are described based on Offshore Technology Conference(OTC) and Society of Petroleum Engineers(SPE) industry publications and press release data. Export lines and infield flowlines are equally represented and many projects used a combination of J-lay, S-lay and reel methods with rigid steel, flexible line, and pipe-in-pipe systems. The average 2014 inflation-adjusted cost for pipeline projects based on OTC/SPE publications was $2.76 million/mi and ranged from $520 000/mi to $12.94 million/mi. High cost pipelines tend to be short segments or specialized pipeline. Excluding the two cost endpoints, the majority of projects ranged from $1 to $6 million/mi. The average inflation-adjusted cost to install deepwater pipelines in the U.S. Gulf of Mexico based on available public data is estimated at $3.1 million/mi.
基金supported by the Department of Science and Technology,Goverment of West Bengal.India[grant No.705(Sanc.)ST/P/S&T/9G-27/2007]
文摘Objective:To develop a rapid,cost effective RT-PCR method for the mass scale diagnosis of such diseases at the vireraia stage to find out the actual disease burden in that area.Methods:For this purpose,cases with the history of only short febrile illness were considered.Thus 157 samples with the history of dengue/chikungunya like illness and only 58 samples with a history of acute encephalitis syndrome(AES)were selected.Results:Out of 157 samples,42 and 74 were detected as dengue and chikungunya,respectively and out of 58 AES cases only 23 could be detected as Japanese encephalitis by this RT-PCR method.Conclusions:This cost effective RT-PCR method can detect the total positive cases that remain undetected by EL1SA method.Moreover,this method is capable to detect the viral RNA from patients'sera even after the appearance of IgM antibody at one fifth costs as compared with the other commercially available kits.
基金the Doctorate Foundation of Northwestern Polytechnical University (Grant No.CX200304)
文摘To making the decision of the developing blue prints,ideal point method was selected to estimate the life cycle cost with effectiveness of torpedo.At the same time,the concept of grey relational entropy of the grey system theory was adopted to compute the distance between each blue print and the ideal point(or negative ideal point).The blue print,nearest to the ideal point and farthest to the negative ideal point,is the best one.As an example,four blue prints of torpedo were estimated.The result indicates the practical value of this method.
文摘On the basis of describing the connotation of agricultural intangible asset and cost method,the technical ideas of appraising by cost method are introduced.The article analyzes the advantages(simple appraisal principle and easy to understand and grasp;overall consideration of various factors related to appraisal result value) and disadvantages(high appraisal cost;difficult to appraise and grasp various appraisal factors) of appraising by cost method.The article also summarizes the precondition of appraising by cost method:it is applicable to appraise the agricultural intangible asset which can be reproduced and afresh developed.Based on the cognition of agricultural intangible asset and the relevant rules of Ministry of Finance on appraisal of intangible asset by using cost method,the model of appraising agricultural intangible asset by cost method is constructed.That is:agricultural intangible asset value = replacement cost of agricultural intangible asset ×newness rate + opportunity cost of agricultural intangible asset.Determine and analyze parameters of the model,in order to offer references for appraisers to appraise agricultural intangible asset value more reasonably.
文摘Despite a multitude of theoretical discussions on China's mixed ownership reform, very few studies have addressed realistic questions concerning the implementation of the reform. The Resolutions of the Third Plenum of the 18 th CPC Central Committee and other reform strategies have outlined the reform of sectors with natural monopoly, including urban public utility sectors. The question is how mixed ownership reform should be carried out in sectors of natural monopoly, or which public utilities sectors should enjoy priority of mixed ownership reform. To answer this question, this paper employs data of large public utility enterprises in China from 1998 to 2008, and estimates the natural monopoly attribute at the industry level and corporate total factor productivity(TFP) using cost function analysis method excluding the impact of product price factor. Based on the difference-indifferences-in-differences(DDD) method of natural experiment, an empirical test is carried out for the relationship among natural monopoly, mixed ownership reform and corporate productivity. Our results suggest that:(1) Statistically, mixed ownership reform cannot significantly increase corporate TFP in sectors with natural monopoly;(2) mixed ownership reform should not be carried out indiscriminately on a nationwide basis and for all public utilities sectors. Such an attempt of reform without distinguishing natural monopoly and the level of competitiveness is fraught with policy uncertainties;(3) relative to sectors with natural monopoly, corporate productivity in competitive sectors after mixed ownership reform will improve more significantly and enjoy greater "policy dividends" of institutional reform. Therefore, mixed ownership reform should be carried out first in competitive sectors.
文摘The In most contingent valuation (CV) studies, WTP (Willingness to pay) and WTA (Willingness to accept) were often used separately, so protesting or no response or even babbling answers are increasing, and the debate persists over the reliability of CV in economic policy analysis. In order to improve the reliability of CV, WTP and WTA is used syn-chronously to estimate the restoration cost of Maqu grassland ecosystem. Data were partly from questionnaire survey, and partly from interviews and authorities. Before conclusions were derived, we assumed these data that came from interviews and authorities were right. The main result is: If we assumed that the degraded grassland of Maqu needs 10 years to be restored, and divided the restoring period into two stages, then the restoration cost was 0.85 × 108 RMB per year in former 4 years, 0.022 × 108 RMB per year in latter 6 years. The total cost of Maqu grassland restoration was 3.62 × 108 RMB. For all the costs of restoration, WTA occupied 94% and WTP only occupied 6%, suggesting that local grassland degradation was mainly caused by overgrazing and that the overloading livestock must be eliminated in order to achieve restoration successfully. Our research also showed that combining WTP and WTA in contingent valuation is very useful in estimating the cost of environmental improvement projects. Of course, whether these results are right or not, further researches are needed in the future, especially for the actual number of livestock in Maqu grassland.
文摘Road transport is a flexible mode of transport and its importance in era of globalization increases. Management of road transport companies is, in this turbulent environment, exposed to many technical, legislative, and economic problems. Especially, the growing economic pressure leads to an urgent requirement of the manager and control system improvement. Activity-based costing (ABC) method is a very powerful tool to improve products, services, processes, and market strategies. ABC allows company management to understand what causes costs and how to manage them. Company under this scheme may get a glimpse of how efficiently a company converts the source value. The main objective of our research was to assess the possibility of application of the ABC method in a transport undertaking. ABC method as a fundamentally different view on the cost in the transport business helps to find the reasons of cost and thereby influences their levels to make better use of resources.. New managerial accounting methods aim to show management what information is needed, how and where this information can be obtained, and how they can be useful for the management of the company's proper planning, decision-making, and control. Information provided by management accounting is often a key factor in the analysis of alternative ways of solving problems. This article focuses on the transport enterprise management and helps to decide on the use of this method in business practice.
基金The authors received specific funding for State Grid Corporation Headquarters Project Support,Key Technologies and Applications of Planning and Decision-Making Based on the Full Cost Chain of the Power Grid,Grant No.5205331800001.
文摘For facing the challenges brought by large-scale renewable energy having access to the system and considering the key technologies of energy Internet,it is very necessary to put forward the location method of distribution network equipment and capacity from the perspective of life cycle cost.Compared with the traditional energy network,the equipment capacity problem of energy interconnected distribution network which involves in electricity network,thermal energy network and natural gas network is comprehensively considered in this paper.On this basis,firstly,the operation architecture of energy interconnected distribution network is designed.Secondly,taking the grid connection location and configuration capacity of key equipment in the system as the control variables and the operation cost of system comprehensive planning in the whole life cycle as the goal,the equipment location and capacity optimization model of energy interconnected distribution network is established.Finally,an IEEE 33 bus energy mutual distribution grid system is taken for example analysis,and the improved chaotic particle swarmoptimization algorithm is used to solve it.The simulation results show that the method proposed in this paper is suitable for the equipment location and capacity planning of energy interconnected distribution network,and it can effectively improve the social and economic benefits of system operation.
文摘At present,with the rapid development of China's economy,the development of the construction industry has made a new breakthrough.Project management requires the construction industry to continuously play its role and value in improving the ability of project management.Earned value method,which is an important way in the field of project management,enables whole project management to rise to a new height.The specific principle of earned value method will be elaborated by fully introducing the specific role of earned value method in engineering projects to provide a reference and basis for practitioners to improve their management ability.