In this paper,the experimental investigation on the performance improvement of conventional stepped solar still is conducted.The steps are covered by the porous material to improve the performance of the conventional ...In this paper,the experimental investigation on the performance improvement of conventional stepped solar still is conducted.The steps are covered by the porous material to improve the performance of the conventional device and increase the evaporation rate.All the parameters,including the temperature on the glass surface,the water temperature inside the evaporation zone,and the amount of water produced in both conventional and modified stepped solar stills are measured and compared.The efficiency of two devices and their exergy efficiency have been calculated.Finally,the economic analysis of both devices has been done to check the economic feasibility of the modified device.The amount of freshwater generated during one day was 2244.4 and 3076.2 mL/m^(2),respectively for the conventional and modified stepped solar stills.As a result,the amount of water produced in one day by modified stepped solar still is 35.5% more than the conventional one.Also,the costs for the conventional and modified stepped solar stills have been calculated as 0.0359 and 0.029$/(L·m^(-2)),respectively.展开更多
The global financial and economic crisis has negatively affected all business units. Tough fight for the market position results in effort to create efficient methods to maintain company＇s competitiveness. Some of sm...The global financial and economic crisis has negatively affected all business units. Tough fight for the market position results in effort to create efficient methods to maintain company＇s competitiveness. Some of small and medium entrepreneurs have started to search the business allies. As an example of such possibility of cooperation the formation of clusters should be mention. The main intention of this paper is to demonstrate possibility for small and medium-sized enterprises （SMEs） to cooperatively penetrate new markets. Attention is focused mainly on a real export-oriented cluster. Ambition is to use costs and benefits analysis to test ability of the cluster to improve chances of companies to penetrate new markets. In order to link this analysis to real life as much as possible, existing cluster was used and on its accomplishments and failures costs and benefits of clustering are demonstrated.展开更多
This study provides basis information for estimating the feasibility of the environmental and ecological forestry construction project in the area. Through the survey in Miyun watershed, the economical benefits of car...This study provides basis information for estimating the feasibility of the environmental and ecological forestry construction project in the area. Through the survey in Miyun watershed, the economical benefits of carbon sequestration in five typical forest types have been studied by calculating the biomass from the timber accumulation data and converting to the money value. The results show that: in the duration of 100 years, at a discount rate of 5%, and 197 RMB yuan/t as the price of the carbon sequestration, the present value (PV) of the carbon sequestration in different forests are: 6900-9300 yuan/ha in Chinese pine forest,6100-8200 yuan/ha in oak forest, 4500-6100 yuan/ha in other broadleaf forests, 2300-3200 yuan/ha in shrubs and 1300-1800 yuan/ha in cypress forest. The annual mean economic benefit of carbon sequestration is 770-1040 yuan/ha. The pine forest has the highest carbon sequestration benefit, followed by oak forest, other broadleaf forest, shrubs, and cypress forest. If the land is suitable for all forests, pine forest and oak forest should be planted in order to sequestrate more carbon.展开更多
文摘In this paper,the experimental investigation on the performance improvement of conventional stepped solar still is conducted.The steps are covered by the porous material to improve the performance of the conventional device and increase the evaporation rate.All the parameters,including the temperature on the glass surface,the water temperature inside the evaporation zone,and the amount of water produced in both conventional and modified stepped solar stills are measured and compared.The efficiency of two devices and their exergy efficiency have been calculated.Finally,the economic analysis of both devices has been done to check the economic feasibility of the modified device.The amount of freshwater generated during one day was 2244.4 and 3076.2 mL/m^(2),respectively for the conventional and modified stepped solar stills.As a result,the amount of water produced in one day by modified stepped solar still is 35.5% more than the conventional one.Also,the costs for the conventional and modified stepped solar stills have been calculated as 0.0359 and 0.029$/(L·m^(-2)),respectively.
文摘The global financial and economic crisis has negatively affected all business units. Tough fight for the market position results in effort to create efficient methods to maintain company＇s competitiveness. Some of small and medium entrepreneurs have started to search the business allies. As an example of such possibility of cooperation the formation of clusters should be mention. The main intention of this paper is to demonstrate possibility for small and medium-sized enterprises （SMEs） to cooperatively penetrate new markets. Attention is focused mainly on a real export-oriented cluster. Ambition is to use costs and benefits analysis to test ability of the cluster to improve chances of companies to penetrate new markets. In order to link this analysis to real life as much as possible, existing cluster was used and on its accomplishments and failures costs and benefits of clustering are demonstrated.
文摘This study provides basis information for estimating the feasibility of the environmental and ecological forestry construction project in the area. Through the survey in Miyun watershed, the economical benefits of carbon sequestration in five typical forest types have been studied by calculating the biomass from the timber accumulation data and converting to the money value. The results show that: in the duration of 100 years, at a discount rate of 5%, and 197 RMB yuan/t as the price of the carbon sequestration, the present value (PV) of the carbon sequestration in different forests are: 6900-9300 yuan/ha in Chinese pine forest,6100-8200 yuan/ha in oak forest, 4500-6100 yuan/ha in other broadleaf forests, 2300-3200 yuan/ha in shrubs and 1300-1800 yuan/ha in cypress forest. The annual mean economic benefit of carbon sequestration is 770-1040 yuan/ha. The pine forest has the highest carbon sequestration benefit, followed by oak forest, other broadleaf forest, shrubs, and cypress forest. If the land is suitable for all forests, pine forest and oak forest should be planted in order to sequestrate more carbon.
