This paper aims to examine New Economics of Labor Migration (NELM) in the northwestern Guangxi, China and investigate the relationships among rural-urban migration, rural household income and local geographical contex...This paper aims to examine New Economics of Labor Migration (NELM) in the northwestern Guangxi, China and investigate the relationships among rural-urban migration, rural household income and local geographical contexts. Stratified sampling and typical case study were adopted and 236 questionnaires were collected from four vil- lages, Daxin, Lixin, Longhe and Yongchang. We analyzed the rural-urban migration rate, household income and local geographical factors, focusing on the ratio of remittance income to total household income. Data descriptions and sta- tistical methods, such as Pearson Chi-square test, Contingency coefficient, Eta, Pearson correlation coefficient, t-test, multiple comparisons (LSD test, Tamhane T2, Dunnett T3 and Dunnet C test) were used. The results are as follows. Rural households’ income is diversified in survey villages so the motivation of rural-urban migration in the study area can be partly explained by NELM. The migration rate of households (the percentage of households with migrants in survey households) in survey villages varies from 50% to 86%, while the proportion of remittance income to house- hold income is in the range of 30% to 80%. In the village of Yongchang, with the least average arable land area per household, the remittance income plays a vital role in household income (80%). And the statistical findings show that the proportion is significantly and negatively correlated with arable land area per household. The conclusion is that di- rect effect of migration, i.e., the contribution of remittance to household income, is negatively correlated with the con- tribution of resources to local income.展开更多
Urban road traffic noise pollution has always been identified as a severe problem that affects urban populants.In developing nation,road traffic noise pollution depends on the composition of heterogeneous traffic comp...Urban road traffic noise pollution has always been identified as a severe problem that affects urban populants.In developing nation,road traffic noise pollution depends on the composition of heterogeneous traffic composition.These traffic compositions contain vehicles,which have different sizes,speeds variations,a different dimension of vehicles.Environmental noise measurements have been carried out during day-time and night-time in different locations of tier-II city of India.The noise levels have been continuously measured over 24 h periods using kimo DB 300 class-2 noise level meter.The data contained in this research paper represent 768 measurement hours.All the information has been used to investigate the time patterns of the noise levels under a wide range of different conditions and to study the relationships between noise levels and traffic in urban areas.Maximum LAeq was observed 73.3 dB(A)at B_(14) location and the minimum was recorded 65.7 dB(A)at C_(3) location,which was greater than the central pollution control board(CPCB)prescribed limits during night time.A major reason for the generation of road traffic noise is due to the equal composition of 2-wheeler and 4-wheeler on the arterial road and heavy vehicles were recorded during morning peak and evening peak even though they are prohibited during peak hours.展开更多
According to the recent policies regarding energy use in buildings and the need of retrofit strategies,the aim of this work is to support policies concerning the installation of ground source heat exchangers in urban ...According to the recent policies regarding energy use in buildings and the need of retrofit strategies,the aim of this work is to support policies concerning the installation of ground source heat exchangers in urban and historical areas,raising the awareness on the potential energy saving achievable with optimal sizing and limited impact on the urban environment.Archetypes have been developed distinguishing among existing and historic buildings,focusing on single-family terrace houses,which are the typical residential buildings in European historic centres.A methodology for the optimal sizing of ground source heat pumps,eventually considering dual-source system or air system has been developed combining simulations of a photovoltaic system to estimate the self-sufficiency and the self-consumption for five orientations of the building.Extreme results have been obtained for warm cli-mates,with negligible heating energy demand and possibly free cooling systems rather than traditional cooling systems needed in wintertime.Penalty temperature was acceptable despite unbalanced energy demands.With proper inclination,photovoltaic systems could provide up to 40%of self-sufficiency share also in northern cli-mates.An energy-economic analysis was carried out obtaining a variety of cases representing a general overview of the European building stock and the potential benefits achievable in terms of renewable energy share,energy savings and economic investments needed to be extended to simulations at urban scale.展开更多
基金Under the auspices of the Key Project of National Natural Science Foundation of China (No. 40635029)"985" Proje- ct of Central University for Nationalities (No. 985-2-103-1)
文摘This paper aims to examine New Economics of Labor Migration (NELM) in the northwestern Guangxi, China and investigate the relationships among rural-urban migration, rural household income and local geographical contexts. Stratified sampling and typical case study were adopted and 236 questionnaires were collected from four vil- lages, Daxin, Lixin, Longhe and Yongchang. We analyzed the rural-urban migration rate, household income and local geographical factors, focusing on the ratio of remittance income to total household income. Data descriptions and sta- tistical methods, such as Pearson Chi-square test, Contingency coefficient, Eta, Pearson correlation coefficient, t-test, multiple comparisons (LSD test, Tamhane T2, Dunnett T3 and Dunnet C test) were used. The results are as follows. Rural households’ income is diversified in survey villages so the motivation of rural-urban migration in the study area can be partly explained by NELM. The migration rate of households (the percentage of households with migrants in survey households) in survey villages varies from 50% to 86%, while the proportion of remittance income to house- hold income is in the range of 30% to 80%. In the village of Yongchang, with the least average arable land area per household, the remittance income plays a vital role in household income (80%). And the statistical findings show that the proportion is significantly and negatively correlated with arable land area per household. The conclusion is that di- rect effect of migration, i.e., the contribution of remittance to household income, is negatively correlated with the con- tribution of resources to local income.
文摘Urban road traffic noise pollution has always been identified as a severe problem that affects urban populants.In developing nation,road traffic noise pollution depends on the composition of heterogeneous traffic composition.These traffic compositions contain vehicles,which have different sizes,speeds variations,a different dimension of vehicles.Environmental noise measurements have been carried out during day-time and night-time in different locations of tier-II city of India.The noise levels have been continuously measured over 24 h periods using kimo DB 300 class-2 noise level meter.The data contained in this research paper represent 768 measurement hours.All the information has been used to investigate the time patterns of the noise levels under a wide range of different conditions and to study the relationships between noise levels and traffic in urban areas.Maximum LAeq was observed 73.3 dB(A)at B_(14) location and the minimum was recorded 65.7 dB(A)at C_(3) location,which was greater than the central pollution control board(CPCB)prescribed limits during night time.A major reason for the generation of road traffic noise is due to the equal composition of 2-wheeler and 4-wheeler on the arterial road and heavy vehicles were recorded during morning peak and evening peak even though they are prohibited during peak hours.
基金developed as part of the GEO4CIVHIC Project,which has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No.792355.
文摘According to the recent policies regarding energy use in buildings and the need of retrofit strategies,the aim of this work is to support policies concerning the installation of ground source heat exchangers in urban and historical areas,raising the awareness on the potential energy saving achievable with optimal sizing and limited impact on the urban environment.Archetypes have been developed distinguishing among existing and historic buildings,focusing on single-family terrace houses,which are the typical residential buildings in European historic centres.A methodology for the optimal sizing of ground source heat pumps,eventually considering dual-source system or air system has been developed combining simulations of a photovoltaic system to estimate the self-sufficiency and the self-consumption for five orientations of the building.Extreme results have been obtained for warm cli-mates,with negligible heating energy demand and possibly free cooling systems rather than traditional cooling systems needed in wintertime.Penalty temperature was acceptable despite unbalanced energy demands.With proper inclination,photovoltaic systems could provide up to 40%of self-sufficiency share also in northern cli-mates.An energy-economic analysis was carried out obtaining a variety of cases representing a general overview of the European building stock and the potential benefits achievable in terms of renewable energy share,energy savings and economic investments needed to be extended to simulations at urban scale.