Based on the characteristics of urban-rural dual economic structure in China,we build a dynamic endogenous urban-rural dual economic model closely linked to China's reality,and carry out mathematical economics ana...Based on the characteristics of urban-rural dual economic structure in China,we build a dynamic endogenous urban-rural dual economic model closely linked to China's reality,and carry out mathematical economics analysis of optimized conditions for urban and rural sectors. The main results show that:(i) The labor growth rate of urban-rural sectors must be greater than the time discount rate,or else there would be a vicious cycle of diminishing returns in the sectors;(ii) The accumulation rate of physical capital and human capital of urban-rural sectors,and the rate of technological progress,need to be greater than the corresponding depreciation rate plus the time discount rate,otherwise there would be a vicious cycle of diminishing returns in the sectors;(iii) The low accumulation rate in the rural sector,and the occurrence of labor outflow,human capital loss and lack of investment,will expand income gap between urban and rural areas,which is a reason for solidification of urban-rural dual economic structure.展开更多
Firstly,this paper reviews and analyzes historic background of urban-rural integration of Chongqing,and the evolution and trend of urban and rural dual economic structure.On the basis of previous researches,it selects...Firstly,this paper reviews and analyzes historic background of urban-rural integration of Chongqing,and the evolution and trend of urban and rural dual economic structure.On the basis of previous researches,it selects factors and variables influencing urban and rural dual economic structure,and establishes an econometric model.By state space Kalman filtering method,it analyzes dynamic influence of factors upon urban-rural dual economic intensity.According to empirical conclusion,it puts forward corresponding policy recommendations for promoting integrated urban and rural economic development of Chongqing.展开更多
The gross output value of township enterprises(XGDP)is used as a variable of township enterprises development.And CXEY is a variable of urban-rural dual economic structure.According to the 1986-2006 Statistical Yearbo...The gross output value of township enterprises(XGDP)is used as a variable of township enterprises development.And CXEY is a variable of urban-rural dual economic structure.According to the 1986-2006 Statistical Yearbook of Chinese Township Enterprises and the 2006 China Statistical Yearbook,effects of the development of township enterprises on the urban-rural dual economic structure are studied by the cointegration analysis.Result shows that without considering other influencing factors,township enterprise development in the years 1979-2005 is the key factor to improve the dual economic structure in urban and rural areas in China.展开更多
More and more empty nest has become a social problem that couldn't ignore. The problem of empty nester is the essence of urban and rural dual structure social changing. The emergence of empty-nesters is a serious pro...More and more empty nest has become a social problem that couldn't ignore. The problem of empty nester is the essence of urban and rural dual structure social changing. The emergence of empty-nesters is a serious problem in China's social development process, with the aging of the population increasing, urban-rural divide more and more obvious. The condition of the human society has gradually formed the rural and the division of labor and the dual structure of the city. This paper expounds the connotation, significance and characteristics of empty nest elderly, analyzes on the problems existing in current urban and rural society and the problem of empty nest elderly in the new situation puts forward the suggestions and countermeasures.展开更多
Taking northern Jiangsu area as an example,economic disparity between urban and rural areas is described according to the data in 2000-2009 Jiangsu Statistical Yearbook.Result shows that there are significant differen...Taking northern Jiangsu area as an example,economic disparity between urban and rural areas is described according to the data in 2000-2009 Jiangsu Statistical Yearbook.Result shows that there are significant differences in the rural and urban economic development in less developed areas,which are mainly reflected in the differences in per capita income,living standard,and Engel coefficient.Reasons for urban and rural economic disparity in less developed areas are analyzed.The asymmetry and immobility of rural and urban resources have objectively caused the income gap between urban and rural residents;urban industrial development,which is faster than agricultural development,has widened the income gap between urban and rural residents;and the differences in comparative labor productivity in rural and urban areas have enlarged their income gap.Countermeasures to minimize the urban and rural economic development gap are put forward,such as deepening the reform,realizing the free flow of economic resources between urban and rural areas,developing rural areas through urban development,exerting the function of urban areas in the coordinated development of urban and rural areas,paying attention to the agriculture and rural areas,and improving the comparative labor productivity of agriculture.展开更多
With rapid urbanization process, the pace of urban sprawl has been quickened and most metropolises have ex-perienced expansions in leaps and bounds in suburbanization, which has greatly changed the urban and rural spa...With rapid urbanization process, the pace of urban sprawl has been quickened and most metropolises have ex-perienced expansions in leaps and bounds in suburbanization, which has greatly changed the urban and rural spatial struc-ture of the metropolis fringe area. In this paper, Shuangliu County is taken as a case, since it is a typical fringe area of Chengdu Metropolis. Based on Landsat TM images of Chengdu City and Shuangliu County obtained in 1985, 2000 and 2004, characteristics of urban and rural spatial structure in Shuangliu County were analyzed, such as core-periphery spa-tial structure and some obvious integration trends. Then the influencing factors for the formation of urban and rural spatial structure were identified, including some natural, social, economic and political factors. According to the discussion of this paper, Shuangliu County is undergoing a key transition and reform period. Its formation of urban and rural spatial structure was affected not only by such common factors as the location, natural background, industrial transition, migra-tion, etc., but also by some unique factors such as city planning and policy guidance, which played an important role in accelerating its uneven spatial structure. The understanding of the role of the influencing factors would be useful for car-rying out spatial management and development planning of metropolis fringe area.展开更多
The relationship between urban-rural integration and regional economic integration is summarized in the paper.Based on the fact,it expressed the necessity and realistic meaning of pushing forward the urban-rural integ...The relationship between urban-rural integration and regional economic integration is summarized in the paper.Based on the fact,it expressed the necessity and realistic meaning of pushing forward the urban-rural integration process synchronously during Jiuquan-Jia yuguan (abbreviate:Jiu-Jia) areas economic integration.The current degree of the urban-rural integration of Jiu-Jia was analyzed by index calculation,and the related conclusions were obtained.Besides,the development concepts and the key works to accelerate the process of Jiu-Jia urban-rural integration were suggested.The results show that the overall level of urban-rural integration in Jiuquan and Jiayuguan is higher than the average level of Gansu Province,but the urban-rural economic development and social development lose the balance and the dual structure is prominent.In the end,three developmental patterns for accelerating the developmental process of urban-rural integration are put forward.Firstly,the government should find the key of the current work and coordinate the construction of infrastructure.Secondly,rural economic industrialization should be promoted.Thirdly,the urbanized social management should be promoted.展开更多
Urbanization is one of the driving forces for the land use change in type and structure, and its prominent effect is to convert rural land to urban land. This paper takes Shan-dong Province as an example to analyze th...Urbanization is one of the driving forces for the land use change in type and structure, and its prominent effect is to convert rural land to urban land. This paper takes Shan-dong Province as an example to analyze the current situation of the mutual conversion between the urban and rural areas from the aspects of the structure of land use, the decreasing tendency of the cultivated land, the changes of land use in urban and rural residential areas. It points out that cultivated land is converted to residential area land, industrial and/or mining area land. The relationship between the urban area land and the cultivated land is more direct; meanwhile, the changes of rural residential area lag behind obviously. The decrease of the cultivated land and the decline of soil quality will be the two difficult problems in the process of urbanization.展开更多
In this paper, the effect of the mediation effect is mainly used to test and analyze the regression model, and most scholars have studied the impact of the modernization of the industrial structure on the income gap. ...In this paper, the effect of the mediation effect is mainly used to test and analyze the regression model, and most scholars have studied the impact of the modernization of the industrial structure on the income gap. However, this paper is from another perspective, based on the social background of high-quality development, the main study is the impact mechanism of urban and rural income gap on the industrial structure, taking the Yangtze River Delta as the main research object, and specifically selecting 22 central cities in the Yangtze River Delta region, which is also one of the highlights of this study. The regression model is constructed by using the intermediary effect, and the four intermediary variables of fiscal expenditure (M<sub>1</sub>), fixed asset investment (M<sub>2</sub>), number of patent applications (M<sub>3</sub>), and total import and export (M<sub>4</sub>) are selected, which represent the role of the government, fixed asset investment, scientific and technological level and opening-up level, and study and analyze the inherent influence mechanism between each variable. Before doing specific research, I consulted the papers and literature of many other outstanding scholars, among which Cheng Yuhong and Cheng Chi’s “The Influence Mechanism of industrial structure of urban and rural income gap” [1] has great reference value for this paper. According to the research results, under the background of high-quality development in the Yangtze River Delta region, the expansion of the income gap between urban and rural areas will inhibit the upgrading of the industrial structure, so it is necessary to focus on building a new type of urbanization, accelerating the construction of an urban innovation system, optimizing the rural employment structure to narrow the income gap between urban and rural areas, and providing impetus for the continuous upgrading of the industrial structure.展开更多
As the gap in income between urban and rural residents bigger and bigger,based on the data from 1978 to 2007,this paper makes an empirical study of the dynamic relation between the fixed assets investment and the diff...As the gap in income between urban and rural residents bigger and bigger,based on the data from 1978 to 2007,this paper makes an empirical study of the dynamic relation between the fixed assets investment and the difference in income between urban and rural residents. The outcome from the study indicates a long-term balance exists between the investment rate of the fixed assets and the difference in income between urban and rural residents. A short-term deviation from the balance can be adjusted through long time. To a certain extent,city-oriented fixed assets investment policy is the main cause of the big gap in income between urban and rural residents. The big gap in income between urban and rural residents in turn reinforces their social status,thus further strengthening the city-oriented instead of countryside-oriented fixed assets investment policy. Based on that,this paper puts forward some suggestions on adjusting the fixed assets investment policy so as to shorten the difference in income between urban and rural residents and realize the goal of harmonious development between city and countryside.展开更多
The urban and rural areas are regarded as two major components of the regional economic system. Only through joint balanced development of the two can we achieve overall economic optimization and social welfare maximi...The urban and rural areas are regarded as two major components of the regional economic system. Only through joint balanced development of the two can we achieve overall economic optimization and social welfare maximization. But the great social division of labor has separated urban areas from rural areas,which casts the shadow of city-oriented theory on cooperative relations between urban and rural areas. Mutual separation between urban and rural settlements and independent development trigger off a range of social problems. We must undertake guidance through rational development path of urban-rural integration,to eliminate the phenomenon of urban-rural dual structure,and promote the sustainable development of population,resources and environment in urban and rural areas as soon as possible.展开更多
Urban and rural dual structure in Western China is obvious.The economic development of the central cities is relatively quick while that of the rural areas is lagging behind.The speeding up of urbanization contributes...Urban and rural dual structure in Western China is obvious.The economic development of the central cities is relatively quick while that of the rural areas is lagging behind.The speeding up of urbanization contributes to the intensively uncoordinated development of urban and rural areas.Besides,the eco-fragile environment,shortage of available water resources,adverse geographic location,and relatively backward social economy restrict the development of urbanization in Western China.However,Western China also has the advantages of backwardness.This paper analyzes the present situation and development trend of urbanization in Western China.The results show that Western China has basically formed a development pattern with"industry promotes agriculture and urban leads to village".Therefore,combined with the present situation of Western China,this paper describes and analyzes the opportunities and challenges that may appear in the process of urbanization in Western China,puts forward the development pattern in which urban and rural areas can gain mutual support and co-development,and provides related recommendations.展开更多
On the basis of introducing relevant theories of Engel's coefficient,this paper analyzes the limitation of these theories in practical application currently in China,for example,continuing to use original theory,n...On the basis of introducing relevant theories of Engel's coefficient,this paper analyzes the limitation of these theories in practical application currently in China,for example,continuing to use original theory,not in line with reality of China;comparison invalidity in length and breadth,is not conducive to relevant analysis;culling out the special factors easily causes distortion of conclusion.Taking rural areas in Hebei Province as an example,this paper analyzes the limitation of Engel's coefficient in analyzing the gap of rural economy:in terms of region horizontally,Engel's coefficient neglects the difference of consumption structure among regions,and difference of economic stages among regions;in terms of time vertically,Engel's coefficient neglects the periodic change of consumption structure and the ratio change of different families in different periods.According to the reality of China's rural areas,the correction model of Engel's coefficient is established as follows.Firstly,Engel's coefficient=Percentage of expenditure variation(food+ education+ medical service) /Percentage of total expenditure variation;Engel's coefficient=Percentage of expenditure variation(food+ education+ medical service) /Percentage of income variation.Secondly,Engel's coefficient=Percentage of expenditure variation of food/Percentage of variation of(total expenditure educational expenditure-medical expenditure.Thirdly,Engel's coefficient=Percentage of expenditure variation of food/Percentage of total expenditure variation.展开更多
In this paper, we have shown that Africa has an enormous wealth of renewable energy resources among the most important in the world such as the strong sunshine, Congo and Nile Rivers respectively among the most powerf...In this paper, we have shown that Africa has an enormous wealth of renewable energy resources among the most important in the world such as the strong sunshine, Congo and Nile Rivers respectively among the most powerful and the longest in the world. We have underlined the presence of important forests, rich subsoil in mineral elements, and strong winds. In addition to a rapidly growing human capital, Africa, therefore, has at its disposal all the factors enabling it to initiate sustainable and inclusive socio-economic development. We have shown that the transformation of these renewable energies is an opportunity for Africa to reach its socio-economic challenges. The development of renewable energies in Africa will be a source of many financial benefits and advantages both in terms of improving living conditions and carrying out activities. The electrical supply of rural areas of Africa represents a considerable issue, which can be a propellant factor in long-term socio-economic development if the conditions of use of clean fuel and cooking technologies, especially sanitary are taken into account. The provision of modern energy services can contribute to the creation of jobs for young people upstream. Among other things, we can note the development of local skills, the creation of income-generating activities, and the improvement of hygiene and health measures which are necessary conditions for family and social well-being. This requires a policy focused, on research in general and in particular on semiconductors that participate in the transformation of photovoltaic solar energy. We have stressed that Africa which is currently experiencing a period of economic growth and sustained transformation must be very looking at in its energy policy and give pride of place to renewable energies to initiate sustainable socio-economic development, equitable and inclusive different social strata both in rural areas and urban areas.展开更多
基金Supported by Chongqing Social Science Planning Project(2010YBJJ13)the Fundamental Research Funds for the Central Universities(XDJK2010C103)+1 种基金Humanities and Social Sciences Youth Project,the Ministry of Education(10YJC630205)Chongqing Key Humanities and Social Sciences Project(SWU 0810026)
文摘Based on the characteristics of urban-rural dual economic structure in China,we build a dynamic endogenous urban-rural dual economic model closely linked to China's reality,and carry out mathematical economics analysis of optimized conditions for urban and rural sectors. The main results show that:(i) The labor growth rate of urban-rural sectors must be greater than the time discount rate,or else there would be a vicious cycle of diminishing returns in the sectors;(ii) The accumulation rate of physical capital and human capital of urban-rural sectors,and the rate of technological progress,need to be greater than the corresponding depreciation rate plus the time discount rate,otherwise there would be a vicious cycle of diminishing returns in the sectors;(iii) The low accumulation rate in the rural sector,and the occurrence of labor outflow,human capital loss and lack of investment,will expand income gap between urban and rural areas,which is a reason for solidification of urban-rural dual economic structure.
基金Supported by Social Science Planning Project of Chongqing(2010YBJJ13)the Fundamental Research Funds for the Central Universities(XDJK2010C103)Ph.D Foundation Project of Southwest University(SWU1209303)
文摘Firstly,this paper reviews and analyzes historic background of urban-rural integration of Chongqing,and the evolution and trend of urban and rural dual economic structure.On the basis of previous researches,it selects factors and variables influencing urban and rural dual economic structure,and establishes an econometric model.By state space Kalman filtering method,it analyzes dynamic influence of factors upon urban-rural dual economic intensity.According to empirical conclusion,it puts forward corresponding policy recommendations for promoting integrated urban and rural economic development of Chongqing.
文摘The gross output value of township enterprises(XGDP)is used as a variable of township enterprises development.And CXEY is a variable of urban-rural dual economic structure.According to the 1986-2006 Statistical Yearbook of Chinese Township Enterprises and the 2006 China Statistical Yearbook,effects of the development of township enterprises on the urban-rural dual economic structure are studied by the cointegration analysis.Result shows that without considering other influencing factors,township enterprise development in the years 1979-2005 is the key factor to improve the dual economic structure in urban and rural areas in China.
文摘More and more empty nest has become a social problem that couldn't ignore. The problem of empty nester is the essence of urban and rural dual structure social changing. The emergence of empty-nesters is a serious problem in China's social development process, with the aging of the population increasing, urban-rural divide more and more obvious. The condition of the human society has gradually formed the rural and the division of labor and the dual structure of the city. This paper expounds the connotation, significance and characteristics of empty nest elderly, analyzes on the problems existing in current urban and rural society and the problem of empty nest elderly in the new situation puts forward the suggestions and countermeasures.
文摘Taking northern Jiangsu area as an example,economic disparity between urban and rural areas is described according to the data in 2000-2009 Jiangsu Statistical Yearbook.Result shows that there are significant differences in the rural and urban economic development in less developed areas,which are mainly reflected in the differences in per capita income,living standard,and Engel coefficient.Reasons for urban and rural economic disparity in less developed areas are analyzed.The asymmetry and immobility of rural and urban resources have objectively caused the income gap between urban and rural residents;urban industrial development,which is faster than agricultural development,has widened the income gap between urban and rural residents;and the differences in comparative labor productivity in rural and urban areas have enlarged their income gap.Countermeasures to minimize the urban and rural economic development gap are put forward,such as deepening the reform,realizing the free flow of economic resources between urban and rural areas,developing rural areas through urban development,exerting the function of urban areas in the coordinated development of urban and rural areas,paying attention to the agriculture and rural areas,and improving the comparative labor productivity of agriculture.
基金Under the auspices of National Natural Science Foundation of China (No 40571056)
文摘With rapid urbanization process, the pace of urban sprawl has been quickened and most metropolises have ex-perienced expansions in leaps and bounds in suburbanization, which has greatly changed the urban and rural spatial struc-ture of the metropolis fringe area. In this paper, Shuangliu County is taken as a case, since it is a typical fringe area of Chengdu Metropolis. Based on Landsat TM images of Chengdu City and Shuangliu County obtained in 1985, 2000 and 2004, characteristics of urban and rural spatial structure in Shuangliu County were analyzed, such as core-periphery spa-tial structure and some obvious integration trends. Then the influencing factors for the formation of urban and rural spatial structure were identified, including some natural, social, economic and political factors. According to the discussion of this paper, Shuangliu County is undergoing a key transition and reform period. Its formation of urban and rural spatial structure was affected not only by such common factors as the location, natural background, industrial transition, migra-tion, etc., but also by some unique factors such as city planning and policy guidance, which played an important role in accelerating its uneven spatial structure. The understanding of the role of the influencing factors would be useful for car-rying out spatial management and development planning of metropolis fringe area.
基金Supported by Development and Reform Commission of Gansu Province
文摘The relationship between urban-rural integration and regional economic integration is summarized in the paper.Based on the fact,it expressed the necessity and realistic meaning of pushing forward the urban-rural integration process synchronously during Jiuquan-Jia yuguan (abbreviate:Jiu-Jia) areas economic integration.The current degree of the urban-rural integration of Jiu-Jia was analyzed by index calculation,and the related conclusions were obtained.Besides,the development concepts and the key works to accelerate the process of Jiu-Jia urban-rural integration were suggested.The results show that the overall level of urban-rural integration in Jiuquan and Jiayuguan is higher than the average level of Gansu Province,but the urban-rural economic development and social development lose the balance and the dual structure is prominent.In the end,three developmental patterns for accelerating the developmental process of urban-rural integration are put forward.Firstly,the government should find the key of the current work and coordinate the construction of infrastructure.Secondly,rural economic industrialization should be promoted.Thirdly,the urbanized social management should be promoted.
文摘Urbanization is one of the driving forces for the land use change in type and structure, and its prominent effect is to convert rural land to urban land. This paper takes Shan-dong Province as an example to analyze the current situation of the mutual conversion between the urban and rural areas from the aspects of the structure of land use, the decreasing tendency of the cultivated land, the changes of land use in urban and rural residential areas. It points out that cultivated land is converted to residential area land, industrial and/or mining area land. The relationship between the urban area land and the cultivated land is more direct; meanwhile, the changes of rural residential area lag behind obviously. The decrease of the cultivated land and the decline of soil quality will be the two difficult problems in the process of urbanization.
文摘In this paper, the effect of the mediation effect is mainly used to test and analyze the regression model, and most scholars have studied the impact of the modernization of the industrial structure on the income gap. However, this paper is from another perspective, based on the social background of high-quality development, the main study is the impact mechanism of urban and rural income gap on the industrial structure, taking the Yangtze River Delta as the main research object, and specifically selecting 22 central cities in the Yangtze River Delta region, which is also one of the highlights of this study. The regression model is constructed by using the intermediary effect, and the four intermediary variables of fiscal expenditure (M<sub>1</sub>), fixed asset investment (M<sub>2</sub>), number of patent applications (M<sub>3</sub>), and total import and export (M<sub>4</sub>) are selected, which represent the role of the government, fixed asset investment, scientific and technological level and opening-up level, and study and analyze the inherent influence mechanism between each variable. Before doing specific research, I consulted the papers and literature of many other outstanding scholars, among which Cheng Yuhong and Cheng Chi’s “The Influence Mechanism of industrial structure of urban and rural income gap” [1] has great reference value for this paper. According to the research results, under the background of high-quality development in the Yangtze River Delta region, the expansion of the income gap between urban and rural areas will inhibit the upgrading of the industrial structure, so it is necessary to focus on building a new type of urbanization, accelerating the construction of an urban innovation system, optimizing the rural employment structure to narrow the income gap between urban and rural areas, and providing impetus for the continuous upgrading of the industrial structure.
基金Supported by Major Humanities and Social Sciences Project of Southwest University(12XDSK002)Key Humanities and Social Sciences Project in Chongqing City(13SKB002)Fundamental Research Funds for the Central Universities in 2014(SWU1409321)
文摘As the gap in income between urban and rural residents bigger and bigger,based on the data from 1978 to 2007,this paper makes an empirical study of the dynamic relation between the fixed assets investment and the difference in income between urban and rural residents. The outcome from the study indicates a long-term balance exists between the investment rate of the fixed assets and the difference in income between urban and rural residents. A short-term deviation from the balance can be adjusted through long time. To a certain extent,city-oriented fixed assets investment policy is the main cause of the big gap in income between urban and rural residents. The big gap in income between urban and rural residents in turn reinforces their social status,thus further strengthening the city-oriented instead of countryside-oriented fixed assets investment policy. Based on that,this paper puts forward some suggestions on adjusting the fixed assets investment policy so as to shorten the difference in income between urban and rural residents and realize the goal of harmonious development between city and countryside.
基金Supported by Key Research Base Foundation of Research Center for Information Industry Development of Shaanxi ProvinceProject of Shaanxi Provincial Department of Education ( 11JK0053)
文摘The urban and rural areas are regarded as two major components of the regional economic system. Only through joint balanced development of the two can we achieve overall economic optimization and social welfare maximization. But the great social division of labor has separated urban areas from rural areas,which casts the shadow of city-oriented theory on cooperative relations between urban and rural areas. Mutual separation between urban and rural settlements and independent development trigger off a range of social problems. We must undertake guidance through rational development path of urban-rural integration,to eliminate the phenomenon of urban-rural dual structure,and promote the sustainable development of population,resources and environment in urban and rural areas as soon as possible.
基金financially supported by the"Strategy and Policies on Environment and Development in Western China" project of "China Council for International Cooperation on Environment and Development(CCICED)"
文摘Urban and rural dual structure in Western China is obvious.The economic development of the central cities is relatively quick while that of the rural areas is lagging behind.The speeding up of urbanization contributes to the intensively uncoordinated development of urban and rural areas.Besides,the eco-fragile environment,shortage of available water resources,adverse geographic location,and relatively backward social economy restrict the development of urbanization in Western China.However,Western China also has the advantages of backwardness.This paper analyzes the present situation and development trend of urbanization in Western China.The results show that Western China has basically formed a development pattern with"industry promotes agriculture and urban leads to village".Therefore,combined with the present situation of Western China,this paper describes and analyzes the opportunities and challenges that may appear in the process of urbanization in Western China,puts forward the development pattern in which urban and rural areas can gain mutual support and co-development,and provides related recommendations.
文摘On the basis of introducing relevant theories of Engel's coefficient,this paper analyzes the limitation of these theories in practical application currently in China,for example,continuing to use original theory,not in line with reality of China;comparison invalidity in length and breadth,is not conducive to relevant analysis;culling out the special factors easily causes distortion of conclusion.Taking rural areas in Hebei Province as an example,this paper analyzes the limitation of Engel's coefficient in analyzing the gap of rural economy:in terms of region horizontally,Engel's coefficient neglects the difference of consumption structure among regions,and difference of economic stages among regions;in terms of time vertically,Engel's coefficient neglects the periodic change of consumption structure and the ratio change of different families in different periods.According to the reality of China's rural areas,the correction model of Engel's coefficient is established as follows.Firstly,Engel's coefficient=Percentage of expenditure variation(food+ education+ medical service) /Percentage of total expenditure variation;Engel's coefficient=Percentage of expenditure variation(food+ education+ medical service) /Percentage of income variation.Secondly,Engel's coefficient=Percentage of expenditure variation of food/Percentage of variation of(total expenditure educational expenditure-medical expenditure.Thirdly,Engel's coefficient=Percentage of expenditure variation of food/Percentage of total expenditure variation.
文摘In this paper, we have shown that Africa has an enormous wealth of renewable energy resources among the most important in the world such as the strong sunshine, Congo and Nile Rivers respectively among the most powerful and the longest in the world. We have underlined the presence of important forests, rich subsoil in mineral elements, and strong winds. In addition to a rapidly growing human capital, Africa, therefore, has at its disposal all the factors enabling it to initiate sustainable and inclusive socio-economic development. We have shown that the transformation of these renewable energies is an opportunity for Africa to reach its socio-economic challenges. The development of renewable energies in Africa will be a source of many financial benefits and advantages both in terms of improving living conditions and carrying out activities. The electrical supply of rural areas of Africa represents a considerable issue, which can be a propellant factor in long-term socio-economic development if the conditions of use of clean fuel and cooking technologies, especially sanitary are taken into account. The provision of modern energy services can contribute to the creation of jobs for young people upstream. Among other things, we can note the development of local skills, the creation of income-generating activities, and the improvement of hygiene and health measures which are necessary conditions for family and social well-being. This requires a policy focused, on research in general and in particular on semiconductors that participate in the transformation of photovoltaic solar energy. We have stressed that Africa which is currently experiencing a period of economic growth and sustained transformation must be very looking at in its energy policy and give pride of place to renewable energies to initiate sustainable socio-economic development, equitable and inclusive different social strata both in rural areas and urban areas.