Do China's silk products only have advantage in number but no pricing power in international market? In this paper, we used the residual demand elasticity model to estimate the international market power of China's...Do China's silk products only have advantage in number but no pricing power in international market? In this paper, we used the residual demand elasticity model to estimate the international market power of China's silk products. The empirical results revealed that China's raw material products such as natural silk products and semi-finished products such as satin products had certain market power in the main export markets, but the finished silk products such as woman's blouse or shirts and shawls had no market power in the target markets including USA and Germany. The scale economy from resource endowment and great market share are the base of the international market power of natural silk products. The advantage from industry agglomeration and great market share are the source of the international market power of satin products. Technical bottlenecks and inefficiency in brand building are the cause of unobvious international market power of China's finished silk products, and the competition from Italy and France has increased the difficulty to enhance market power. In order to consolidate and improve the international market power of China's silk products, it is suggested to stabilize the production scale and strengthen industrial base, to speed up the resources integration and optimize the industrial distribution, to strengthen science and technology innovation and adjust product structure, to speed up the brand construction and enhance the influence of brand, and to enlarge the scale of organization and achieve scale economies.展开更多
Express Mail Service (EMS) is the most competitive one of the post services. Price competition is the core of market competition and so for EMS. In this paper, we calculate the coefficient of demand elasticity and the...Express Mail Service (EMS) is the most competitive one of the post services. Price competition is the core of market competition and so for EMS. In this paper, we calculate the coefficient of demand elasticity and then put forward the price strategy for EMS to increase its competitive power.展开更多
Demand for food plays an important role in the adjustment of prices for agricultural products and for adjusting agricultural structure.By using the extended linear expenditure system(ELES),we analyzed the food consump...Demand for food plays an important role in the adjustment of prices for agricultural products and for adjusting agricultural structure.By using the extended linear expenditure system(ELES),we analyzed the food consumption structure of rural residents in the Ganzhou district of Zhangye city,and determined the basic food-consumption demand,the marginal propensity of consumption,the income elasticities of demand,and the own-price and cross-price elasticities of local rural residents,all of which illustrate the influencing factors on food consumption of rural residents and for forecasting the food-consumption structure.Those analyses show the following:the rural residents’ expenditure on household basic food consumption reaches about 7,050.35 Yuan;the marginal propensities of consumption of fruits and vegetables are relatively high(0.062 and 0.106,respectively),followed by meat(0.044);the demands for various foods are increasing as income increases,with the largest income elasticity of demand corresponding to fruits(1.354) and the lowest to cereal(0.310);fruits and vegetables have relatively high own-price elasticities(respectively-0.879 and-0.442),with the cereal having the lowest one(-0.184).An increase in cereal prices would greatly affect demand for other products;with the rising size of rural households,the consumption for meat is decreasing whereas it is increasing for cereal.The improvement of household education levels will lead to the increase of fruit consumption(E = 0.297),which indicates that people will pay more attention to diet and nutrition structure with the improvement of education.Further,although the amount of cereal expenditure is continually growing,the share will be declining with the increase of household income in 2006-2012.For all these reasons,therefore,the government should encourage the cultivation of economic crops and guide the development of stockbreeding to ensure the stability of cereal output.In order to attain the balance between supply and demand,it is important to rationally adjust the prices of fruits and vegetables on the basis of the stable price of cereal.展开更多
“Low profit and high sales” is a strategy to increase sales volume by reducing the profit of unit goods, so that businesses can gain more profits. For flexible goods, price reduction can increase the total revenue, ...“Low profit and high sales” is a strategy to increase sales volume by reducing the profit of unit goods, so that businesses can gain more profits. For flexible goods, price reduction can increase the total revenue, but when the goods are lack of flexibility, price reduction will reduce the total revenue. In this paper, according to the sales data provided by a supermarket, we preprocess the data, establish appropriate indicators to measure the daily discount strength of the mall, and establish a mathematical model between the discount strength, sales and profit margin. Through these models, we found that meager profits do bring up sales, but too low discounts can also hurt total profits. In addition, when shopping malls implement discount promotions, they will also bring some negative effects, and we give some suggestions for this.展开更多
Efficiently solving the user equilibrium traffic assignment problem with elastic demand(UE-TAPED)for transportation networks is a critical problem for transportation studies.Most existing UE-TAPED algorithms are desig...Efficiently solving the user equilibrium traffic assignment problem with elastic demand(UE-TAPED)for transportation networks is a critical problem for transportation studies.Most existing UE-TAPED algorithms are designed using a sequential computing scheme,which cannot take advantage of advanced parallel computing power.Therefore,this study focuses on model decomposition and parallelization,proposing an origin-based formulation for UE-TAPED and proving an equivalent reformulation of the original problem.Furthermore,the alternative direction method of multipliers(ADMM)is employed to decompose the original problem into independent link-based subproblems,which can solve large-scale problems with small storage space.In addition,to enhance the efficiency of our algorithm,the parallel computing technology with optimal parallel computing schedule is implemented to solve the link-based subproblems.Numerical experiments are performed to validate the computation efficiency of the proposed parallel algorithm.展开更多
This paper presents a network equilibrium formulation for modeling commuters' travel choices in a bimodal transport system with park-and-ride (P&R) trips while the total demand is elastic to the congestion level o...This paper presents a network equilibrium formulation for modeling commuters' travel choices in a bimodal transport system with park-and-ride (P&R) trips while the total demand is elastic to the congestion level of the network. A super-network approach is adopted in the proposed model. It is assumed that commuters' trips are categorized into two types, auto mode only and a combined mode with both auto and transit modes. The former is referred to as the pure mode trip and the latter as the P&R mode trip. The proposed model simultaneously considers the commuter's choice of the pure mode versus the P&R mode, the choice of parking location for the pure mode, the choice of transfer point for the P&R mode, as well as the route choice for each mode. The demand elasticity of transport system, the capacity constraints of transport facilities, and the congestion interaction throughout the super-network are also explicitly incorporated into the proposed model. The results of the numerical experiment show the following key findings: (i) traditional parking/P&R models may overestimate or underestimate travel demand distribution over network; (ii) parking/P&R, transit scheduling, and carpooling schemes bring significant impacts on commuters' travel behavior and network performance; and (iii) different transport policies may be to some extent mutually substituted .展开更多
How to effectively use the multi-energy demand elasticity of users to bid in the multi-energy market and formulate multi-energy retail packages is an urgent problem which needs to be solved by integrated energy servic...How to effectively use the multi-energy demand elasticity of users to bid in the multi-energy market and formulate multi-energy retail packages is an urgent problem which needs to be solved by integrated energy service providers(IESPs)to attract more users and reduce operating costs.This paper presents a unified clearing of electricity and natural gas based on a bi-level bidding and multi-energy retail price formulation method for IESPs considering multi-energy demand elasticity.First,we propose an operating structure of IESPs in the wholesale and retail energy markets.The multi-energy demand elasticity model of retail-side users and a retail price model for electricity,gas,heat and cooling are established.Secondly,a bi-level bidding model for IESPs considering multi-energy demand elasticity is established to provide IESPs with wholesale-side bidding decisions and retail-side energy retail price decisions.Finally,an example is given to verify the proposed method.The results show that the method improves the total social welfare of the electricity and natural gas markets by 7.99%and the profit of IESPs by 1.40%.It can reduce the variance of the electricity,gas,and cooling load curves,especially the reduction of the variance of the electricity load curve can which reach 79.90%.It can be seen that the research in this paper has a positive effect on repairing the limitations of integrated energy trading research and improving the economics of the operation of IESPs.展开更多
The growing penetration of electric vehicles(EVs)and the popularity of fast charging stations(FCSs)have greatly strengthened the coupling of the urban power network(PN)and traffic network(TN).In this paper,a potential...The growing penetration of electric vehicles(EVs)and the popularity of fast charging stations(FCSs)have greatly strengthened the coupling of the urban power network(PN)and traffic network(TN).In this paper,a potential security threat of the PN-TN coupling is revealed.Different from traditional loads,a regional FCS outage can lead to both the spatial and temporal redistribution of EV charging loads due to EV mobility,which further leads to a power flow redistribution.To assess the resulting potential threats,an integrated PN-TN modeling framework is developed,where the PN is described by a direct current optimal power flow model,and the TN is depicted by an energy-constraint traffic assignment problem.To protect the privacy of the two networks,an FCS outage distribution factor is proposed to describe the spatial-temporal redistribution ratio of the charging load among the remaining I FCSs.Moreover,to protect the security of the coupled networks,a price-based preventive regulation method,based on the spatial demand elasticity of the EV charging load,is developed to reallocate the charging load as a solution for insecure situations.Numerical simulation results validate the existence of the PN-TN coupling threat and demonstrate the effectiveness of the regulation method to exploit the spatial flexibility of EV loads.展开更多
China is believed to have gained immensely from its admission into to the World Trade Organization (WTO) in 2001. One of the direct gains comes from the lessening of deadweight loss (DWL) due to tariff reduction. ...China is believed to have gained immensely from its admission into to the World Trade Organization (WTO) in 2001. One of the direct gains comes from the lessening of deadweight loss (DWL) due to tariff reduction. Conventional measures for DWL, however, are too aggregate to capture the trade policies, which are determined at a much higher disaggregated level, and ignore the interactions between tariff and corresponding import demand as suggested by theories. In this paper, we first systematically estimate the import demand elasticities at a highly disaggregated level and then match them with the most detailed lines of the applied tariff for the most favored nations as reported by the WTO. Using the detailed matching data, we construct Feenstra's (1995) simplified trade restrictiveness index (TRI), which captures the covariance of tariff and the corresponding demand elasticity. Finally, we use the TRI to compute the DWL from1997 to 2008 and find that the DWL due to the tariff barrier was reduced to 0.73% of GNI in 2008, noticeably lower than the highest previous mark of 4.58% of GNI in 2001.展开更多
基金Supported by the Earmarked Fund for China Agriculture Research System(CARS-22)
文摘Do China's silk products only have advantage in number but no pricing power in international market? In this paper, we used the residual demand elasticity model to estimate the international market power of China's silk products. The empirical results revealed that China's raw material products such as natural silk products and semi-finished products such as satin products had certain market power in the main export markets, but the finished silk products such as woman's blouse or shirts and shawls had no market power in the target markets including USA and Germany. The scale economy from resource endowment and great market share are the base of the international market power of natural silk products. The advantage from industry agglomeration and great market share are the source of the international market power of satin products. Technical bottlenecks and inefficiency in brand building are the cause of unobvious international market power of China's finished silk products, and the competition from Italy and France has increased the difficulty to enhance market power. In order to consolidate and improve the international market power of China's silk products, it is suggested to stabilize the production scale and strengthen industrial base, to speed up the resources integration and optimize the industrial distribution, to strengthen science and technology innovation and adjust product structure, to speed up the brand construction and enhance the influence of brand, and to enlarge the scale of organization and achieve scale economies.
文摘Express Mail Service (EMS) is the most competitive one of the post services. Price competition is the core of market competition and so for EMS. In this paper, we calculate the coefficient of demand elasticity and then put forward the price strategy for EMS to increase its competitive power.
基金the funding from the National Natural Science Foundation of China (No. 40671076)CAS western Action Plan (2),"Strategy Research on Basin Integrated Water Resources Management" (KZCX2-XB2-04-04)
文摘Demand for food plays an important role in the adjustment of prices for agricultural products and for adjusting agricultural structure.By using the extended linear expenditure system(ELES),we analyzed the food consumption structure of rural residents in the Ganzhou district of Zhangye city,and determined the basic food-consumption demand,the marginal propensity of consumption,the income elasticities of demand,and the own-price and cross-price elasticities of local rural residents,all of which illustrate the influencing factors on food consumption of rural residents and for forecasting the food-consumption structure.Those analyses show the following:the rural residents’ expenditure on household basic food consumption reaches about 7,050.35 Yuan;the marginal propensities of consumption of fruits and vegetables are relatively high(0.062 and 0.106,respectively),followed by meat(0.044);the demands for various foods are increasing as income increases,with the largest income elasticity of demand corresponding to fruits(1.354) and the lowest to cereal(0.310);fruits and vegetables have relatively high own-price elasticities(respectively-0.879 and-0.442),with the cereal having the lowest one(-0.184).An increase in cereal prices would greatly affect demand for other products;with the rising size of rural households,the consumption for meat is decreasing whereas it is increasing for cereal.The improvement of household education levels will lead to the increase of fruit consumption(E = 0.297),which indicates that people will pay more attention to diet and nutrition structure with the improvement of education.Further,although the amount of cereal expenditure is continually growing,the share will be declining with the increase of household income in 2006-2012.For all these reasons,therefore,the government should encourage the cultivation of economic crops and guide the development of stockbreeding to ensure the stability of cereal output.In order to attain the balance between supply and demand,it is important to rationally adjust the prices of fruits and vegetables on the basis of the stable price of cereal.
文摘“Low profit and high sales” is a strategy to increase sales volume by reducing the profit of unit goods, so that businesses can gain more profits. For flexible goods, price reduction can increase the total revenue, but when the goods are lack of flexibility, price reduction will reduce the total revenue. In this paper, according to the sales data provided by a supermarket, we preprocess the data, establish appropriate indicators to measure the daily discount strength of the mall, and establish a mathematical model between the discount strength, sales and profit margin. Through these models, we found that meager profits do bring up sales, but too low discounts can also hurt total profits. In addition, when shopping malls implement discount promotions, they will also bring some negative effects, and we give some suggestions for this.
基金supported by the National Natural Science Foundation of China(Nos.52302391,5202375,and 52131203)the Natural Science Foundation of Jiangsu Province,China(No.BK20210247)the Fundamental Research Funds for the Central Universities,China(No.2242022R40025).
文摘Efficiently solving the user equilibrium traffic assignment problem with elastic demand(UE-TAPED)for transportation networks is a critical problem for transportation studies.Most existing UE-TAPED algorithms are designed using a sequential computing scheme,which cannot take advantage of advanced parallel computing power.Therefore,this study focuses on model decomposition and parallelization,proposing an origin-based formulation for UE-TAPED and proving an equivalent reformulation of the original problem.Furthermore,the alternative direction method of multipliers(ADMM)is employed to decompose the original problem into independent link-based subproblems,which can solve large-scale problems with small storage space.In addition,to enhance the efficiency of our algorithm,the parallel computing technology with optimal parallel computing schedule is implemented to solve the link-based subproblems.Numerical experiments are performed to validate the computation efficiency of the proposed parallel algorithm.
基金Supported by the Research Grants Council of the Hong Kong Special Administrative Region (No. PolyU 5084/05E, PolyU 5143/03E, and HKU 7126/04E)the China Postdoctoral Science Foundation (No. 20060400573)
文摘This paper presents a network equilibrium formulation for modeling commuters' travel choices in a bimodal transport system with park-and-ride (P&R) trips while the total demand is elastic to the congestion level of the network. A super-network approach is adopted in the proposed model. It is assumed that commuters' trips are categorized into two types, auto mode only and a combined mode with both auto and transit modes. The former is referred to as the pure mode trip and the latter as the P&R mode trip. The proposed model simultaneously considers the commuter's choice of the pure mode versus the P&R mode, the choice of parking location for the pure mode, the choice of transfer point for the P&R mode, as well as the route choice for each mode. The demand elasticity of transport system, the capacity constraints of transport facilities, and the congestion interaction throughout the super-network are also explicitly incorporated into the proposed model. The results of the numerical experiment show the following key findings: (i) traditional parking/P&R models may overestimate or underestimate travel demand distribution over network; (ii) parking/P&R, transit scheduling, and carpooling schemes bring significant impacts on commuters' travel behavior and network performance; and (iii) different transport policies may be to some extent mutually substituted .
基金supported in part by the National Key R&D Program of China(2018YFB0905000)the Science and Technology Project of the State Grid Corporation of China(SGTJDK 00DWJS1800232)。
文摘How to effectively use the multi-energy demand elasticity of users to bid in the multi-energy market and formulate multi-energy retail packages is an urgent problem which needs to be solved by integrated energy service providers(IESPs)to attract more users and reduce operating costs.This paper presents a unified clearing of electricity and natural gas based on a bi-level bidding and multi-energy retail price formulation method for IESPs considering multi-energy demand elasticity.First,we propose an operating structure of IESPs in the wholesale and retail energy markets.The multi-energy demand elasticity model of retail-side users and a retail price model for electricity,gas,heat and cooling are established.Secondly,a bi-level bidding model for IESPs considering multi-energy demand elasticity is established to provide IESPs with wholesale-side bidding decisions and retail-side energy retail price decisions.Finally,an example is given to verify the proposed method.The results show that the method improves the total social welfare of the electricity and natural gas markets by 7.99%and the profit of IESPs by 1.40%.It can reduce the variance of the electricity,gas,and cooling load curves,especially the reduction of the variance of the electricity load curve can which reach 79.90%.It can be seen that the research in this paper has a positive effect on repairing the limitations of integrated energy trading research and improving the economics of the operation of IESPs.
基金supported by Beijing Natural Science Foundation(No.JQ18008).
文摘The growing penetration of electric vehicles(EVs)and the popularity of fast charging stations(FCSs)have greatly strengthened the coupling of the urban power network(PN)and traffic network(TN).In this paper,a potential security threat of the PN-TN coupling is revealed.Different from traditional loads,a regional FCS outage can lead to both the spatial and temporal redistribution of EV charging loads due to EV mobility,which further leads to a power flow redistribution.To assess the resulting potential threats,an integrated PN-TN modeling framework is developed,where the PN is described by a direct current optimal power flow model,and the TN is depicted by an energy-constraint traffic assignment problem.To protect the privacy of the two networks,an FCS outage distribution factor is proposed to describe the spatial-temporal redistribution ratio of the charging load among the remaining I FCSs.Moreover,to protect the security of the coupled networks,a price-based preventive regulation method,based on the spatial demand elasticity of the EV charging load,is developed to reallocate the charging load as a solution for insecure situations.Numerical simulation results validate the existence of the PN-TN coupling threat and demonstrate the effectiveness of the regulation method to exploit the spatial flexibility of EV loads.
基金Acknowledgements We are grateful to the participants at CESifo Venice Summer Institute workshop on "China and the Global Economy Post Crisis" for their invaluable comments. All errors in this paper are ours. Bo Chen acknowledges the financial support of the Ministry of Education of China (No. 09YJC790180) and of the Natural Science Foundation of China (No. 71103116).
文摘China is believed to have gained immensely from its admission into to the World Trade Organization (WTO) in 2001. One of the direct gains comes from the lessening of deadweight loss (DWL) due to tariff reduction. Conventional measures for DWL, however, are too aggregate to capture the trade policies, which are determined at a much higher disaggregated level, and ignore the interactions between tariff and corresponding import demand as suggested by theories. In this paper, we first systematically estimate the import demand elasticities at a highly disaggregated level and then match them with the most detailed lines of the applied tariff for the most favored nations as reported by the WTO. Using the detailed matching data, we construct Feenstra's (1995) simplified trade restrictiveness index (TRI), which captures the covariance of tariff and the corresponding demand elasticity. Finally, we use the TRI to compute the DWL from1997 to 2008 and find that the DWL due to the tariff barrier was reduced to 0.73% of GNI in 2008, noticeably lower than the highest previous mark of 4.58% of GNI in 2001.