As the international trading system has developed with the division of Global value Chains (GVCS), the export trade of Brazil, Russia, India, China, and South Africa (BRICS) has grown rapidly. The resulting growth of ...As the international trading system has developed with the division of Global value Chains (GVCS), the export trade of Brazil, Russia, India, China, and South Africa (BRICS) has grown rapidly. The resulting growth of carbon emissions has drawn wide attention from the international community, necessitating the comparison of the trade benefits and environmental costs of the BRICS participation in GVCS. Based on the Eora database, this paper constructs a decomposition framework for the calculation of export value-added and embodied carbon, based on a multi-region input-output (MRIO) model. The trade benefits and environmental costs paid by the BRICS’ total exports from 1990 to 2015 were measured and the imbalance was analyzed, along with the causes. The results show that the main value-added and carbon embodied in the BRICS’ exports originate from their own countries, and the domestic value-added content of the BRICS’ exports decreased while the foreign value-added content increased.展开更多
On the basis of measuring the bilateral trade costs between China and 86 trade partners and the aggregate trade costs from 2000 to 2013,this paper takes China’s vertical specialization reality into account,to do an e...On the basis of measuring the bilateral trade costs between China and 86 trade partners and the aggregate trade costs from 2000 to 2013,this paper takes China’s vertical specialization reality into account,to do an empirical study on the impact of China’s aggregate trade costs on comparative advantages and export share of 17 two-digit ISIC manufacturing industries,and to conduct these types of robust tests in order to eliminate endogeneity bias.The results show that China’s aggregate trade costs are declining,but it is still 1/3 higher than that of developed countries of 10 years ago;bilateral trade costs between China and some countries even rise instead;aggregate trade costs are the determinants,not only of‘global’and‘local’comparative advantages,but also of export share of China’s manufacturing products,and its effect is stronger in industries with higher trade cost intensity.Therefore,we should consider the product composition on trade cost intensity and domestic value-added value(DVAR),and reduce trade costs in order to promote the export of products with higher domestic value-added rate,and to realize the substantial transformation of foreign trade growth mode.展开更多
It is very difficult to estimate exact values of time and cost of an activity in project scheduling process because many uncertain factors, such as weather, productivity level, human factors etc. , dynamically affect ...It is very difficult to estimate exact values of time and cost of an activity in project scheduling process because many uncertain factors, such as weather, productivity level, human factors etc. , dynamically affect them during project implementation process. A GAs-based fully fuzzy optimal time-cost trade-off model is presented based on fuzzy sets and genetic algorithms (GAs). In tihs model all parameters and variables are characteristics by fuzzy numbers. And then GAs is adopted to search for the optimal solution to this model. The method solves the time-cost trade-off problems under an uncertain environment and is proved practicable through a giving example in ship building scheduling.展开更多
Time-cost trade off problem (TCTP), known in the literature as project crashing problem (PCP) and project speeding up problem (PSP) is a part of project management in planning phase. In this problem, determining the o...Time-cost trade off problem (TCTP), known in the literature as project crashing problem (PCP) and project speeding up problem (PSP) is a part of project management in planning phase. In this problem, determining the optimal levels of activity durations and activity costs which satisfy the project goal(s), leads to a balance between the project completion time and the project total cost. A large amount of literature has studied this problem under various behavior of cost function. But, in all of them, influence of discount has not been in-vestigated. Hence, in this paper, TCTP would be studied considering the influence of discount on the re-source price, using genetic algorithm (GA). The performance of proposed idea has been tested on a medium scale test problem and several computational experiments have been conducted to investigate the appropriate levels of proposed GA considering accuracy and computational time.展开更多
文摘As the international trading system has developed with the division of Global value Chains (GVCS), the export trade of Brazil, Russia, India, China, and South Africa (BRICS) has grown rapidly. The resulting growth of carbon emissions has drawn wide attention from the international community, necessitating the comparison of the trade benefits and environmental costs of the BRICS participation in GVCS. Based on the Eora database, this paper constructs a decomposition framework for the calculation of export value-added and embodied carbon, based on a multi-region input-output (MRIO) model. The trade benefits and environmental costs paid by the BRICS’ total exports from 1990 to 2015 were measured and the imbalance was analyzed, along with the causes. The results show that the main value-added and carbon embodied in the BRICS’ exports originate from their own countries, and the domestic value-added content of the BRICS’ exports decreased while the foreign value-added content increased.
文摘On the basis of measuring the bilateral trade costs between China and 86 trade partners and the aggregate trade costs from 2000 to 2013,this paper takes China’s vertical specialization reality into account,to do an empirical study on the impact of China’s aggregate trade costs on comparative advantages and export share of 17 two-digit ISIC manufacturing industries,and to conduct these types of robust tests in order to eliminate endogeneity bias.The results show that China’s aggregate trade costs are declining,but it is still 1/3 higher than that of developed countries of 10 years ago;bilateral trade costs between China and some countries even rise instead;aggregate trade costs are the determinants,not only of‘global’and‘local’comparative advantages,but also of export share of China’s manufacturing products,and its effect is stronger in industries with higher trade cost intensity.Therefore,we should consider the product composition on trade cost intensity and domestic value-added value(DVAR),and reduce trade costs in order to promote the export of products with higher domestic value-added rate,and to realize the substantial transformation of foreign trade growth mode.
基金Supported by the National High-Tech. R&D Program for CIMS (NO. 2003AA414060).
文摘It is very difficult to estimate exact values of time and cost of an activity in project scheduling process because many uncertain factors, such as weather, productivity level, human factors etc. , dynamically affect them during project implementation process. A GAs-based fully fuzzy optimal time-cost trade-off model is presented based on fuzzy sets and genetic algorithms (GAs). In tihs model all parameters and variables are characteristics by fuzzy numbers. And then GAs is adopted to search for the optimal solution to this model. The method solves the time-cost trade-off problems under an uncertain environment and is proved practicable through a giving example in ship building scheduling.
文摘Time-cost trade off problem (TCTP), known in the literature as project crashing problem (PCP) and project speeding up problem (PSP) is a part of project management in planning phase. In this problem, determining the optimal levels of activity durations and activity costs which satisfy the project goal(s), leads to a balance between the project completion time and the project total cost. A large amount of literature has studied this problem under various behavior of cost function. But, in all of them, influence of discount has not been in-vestigated. Hence, in this paper, TCTP would be studied considering the influence of discount on the re-source price, using genetic algorithm (GA). The performance of proposed idea has been tested on a medium scale test problem and several computational experiments have been conducted to investigate the appropriate levels of proposed GA considering accuracy and computational time.
