Numerical simulation study is conducted for a pressurized spouted fluidized bed coal carbonizer, in which hydrodynamics of pressurized spouted fluidized bed, chemical reactions and energy balance are taken into accoun...Numerical simulation study is conducted for a pressurized spouted fluidized bed coal carbonizer, in which hydrodynamics of pressurized spouted fluidized bed, chemical reactions and energy balance are taken into account. The effect of operating conditions such as bed pressure, air and steam mass flow ratio, temperature on product compositions in the bed is investigated. According to the calculated results, bed pressure and bed temperature have the key effects on coal semi gasification.展开更多
Using the data of China's listed companies during 2010-2014 as samples, this paper employs the PSM and DID methods to respectively investigate the effects of BTto-VAT reform on the turnover tax burden for companie...Using the data of China's listed companies during 2010-2014 as samples, this paper employs the PSM and DID methods to respectively investigate the effects of BTto-VAT reform on the turnover tax burden for companies in pilot regions(Shanghai and eight other provinces and municipalities) and the rest of China. Our study arrived at the following findings: Compared with pilot sectors in non-pilot regions, BT-to-VAT reform has no significant effect on the turnover tax burden of pilot companies in pilot regions; compared with non-pilot companies, BT-to-VAT reform slightly increased the turnover tax burden in the short run and somewhat reduced the turnover tax burden for pilot companies in the long run. Further differentiation of ownership nature led to the discovery that BT-toVAT reform somewhat reduced the turnover tax burden of SOEs and central SOEs, slightly increased the turnover tax burden for non-SOEs and local SOEs in pilot regions, slightly increased the turnover tax burden in the short run and somewhat reduced the turnover tax burden in the long run after nationwide pilot programs were introduced; BT-to-VAT reform has more significant effects on non-SOEs and local SOEs. In general, BT-to-VAT reform has no significant effects on the turnover tax burden of companies and after differentiating pilot regions, pilot sectors and ownership nature, we did not discover any significant effect, which is generally consistent with policy expectations.展开更多
Seoul metropolitan subway network is known to be the one of the most heavily used transportation means in the world. The subway cabins are naturally ventilated when the cabin doors are opened and through the gaps caus...Seoul metropolitan subway network is known to be the one of the most heavily used transportation means in the world. The subway cabins are naturally ventilated when the cabin doors are opened and through the gaps caused by the incomplete air-tightening of cabin bodies. Although, subway trains are equipped with a mechanical exhaust fan, the apparatus is rarely operated due to the problem of heating/cooling efficiency especially in the summer and winter seasons. In this study, we analyzed the transient CO2 （carbon dioxide） concentration level during the journey of a subway cabin when a heavy load of passengers of up to 200% of designed capacity using a CFD （computational fluid dynamics） analysis. With an increased journey time, the CO2 concentration increased by up to 5,000 ppm depending on passenger load. Through the operation of a mechanical exhaust fan, the high concentration of CO2 decreased down to 1,500 ppm. The effect of the exhaust fan operating on the dilution of indoor air was estimated by comparison with a closed cabin. In addition, the energy consumption for cooling in summer time was assessed for exhaust fan operations.展开更多
文摘Numerical simulation study is conducted for a pressurized spouted fluidized bed coal carbonizer, in which hydrodynamics of pressurized spouted fluidized bed, chemical reactions and energy balance are taken into account. The effect of operating conditions such as bed pressure, air and steam mass flow ratio, temperature on product compositions in the bed is investigated. According to the calculated results, bed pressure and bed temperature have the key effects on coal semi gasification.
基金National Accounting Research Key Project of the Ministry of Finance"A study on the Supervision and Governance Functions,Implementing Pathway and Promotion Mechanism of Audits(Grant No.2015KJA017)"General Project of Hunan Provincial Foundation for Philosophical,Social and Scientific Research"Study on the Supervision and Governance Functions of Audits in the New Normal"(Grant No.l5YBA079)Social Sciences Foundation of China(SSFC)"A study on the Supervision of Asset Mispricing,the Mitigation of Systematic Financial Risks and Dynamic Supervision"(Grant No.l6BGL050)
文摘Using the data of China's listed companies during 2010-2014 as samples, this paper employs the PSM and DID methods to respectively investigate the effects of BTto-VAT reform on the turnover tax burden for companies in pilot regions(Shanghai and eight other provinces and municipalities) and the rest of China. Our study arrived at the following findings: Compared with pilot sectors in non-pilot regions, BT-to-VAT reform has no significant effect on the turnover tax burden of pilot companies in pilot regions; compared with non-pilot companies, BT-to-VAT reform slightly increased the turnover tax burden in the short run and somewhat reduced the turnover tax burden for pilot companies in the long run. Further differentiation of ownership nature led to the discovery that BT-toVAT reform somewhat reduced the turnover tax burden of SOEs and central SOEs, slightly increased the turnover tax burden for non-SOEs and local SOEs in pilot regions, slightly increased the turnover tax burden in the short run and somewhat reduced the turnover tax burden in the long run after nationwide pilot programs were introduced; BT-to-VAT reform has more significant effects on non-SOEs and local SOEs. In general, BT-to-VAT reform has no significant effects on the turnover tax burden of companies and after differentiating pilot regions, pilot sectors and ownership nature, we did not discover any significant effect, which is generally consistent with policy expectations.
文摘Seoul metropolitan subway network is known to be the one of the most heavily used transportation means in the world. The subway cabins are naturally ventilated when the cabin doors are opened and through the gaps caused by the incomplete air-tightening of cabin bodies. Although, subway trains are equipped with a mechanical exhaust fan, the apparatus is rarely operated due to the problem of heating/cooling efficiency especially in the summer and winter seasons. In this study, we analyzed the transient CO2 （carbon dioxide） concentration level during the journey of a subway cabin when a heavy load of passengers of up to 200% of designed capacity using a CFD （computational fluid dynamics） analysis. With an increased journey time, the CO2 concentration increased by up to 5,000 ppm depending on passenger load. Through the operation of a mechanical exhaust fan, the high concentration of CO2 decreased down to 1,500 ppm. The effect of the exhaust fan operating on the dilution of indoor air was estimated by comparison with a closed cabin. In addition, the energy consumption for cooling in summer time was assessed for exhaust fan operations.
