BACKGROUND The efficacy and safety of proprotein convertase subtilisin/kexin type 9(PCSK-9) inhibitors were confirmed by several clinical trials, but its effectiveness in routine clinical practice in China has not bee...BACKGROUND The efficacy and safety of proprotein convertase subtilisin/kexin type 9(PCSK-9) inhibitors were confirmed by several clinical trials, but its effectiveness in routine clinical practice in China has not been evaluated. This study aims to describe the real world effectiveness of PCSK-9 inhibitors combined with statins compared with statins-based therapy among patients with very high risk of atherosclerotic cardiovascular disease(ASCVD).METHODS This is a multi-center observational study, enrolled patients from 32 hospitals who underwent percutaneous coronary intervention(PCI) from January to June in 2019. There are 453 patients treated with PCSK-9 inhibitors combined with statins in PCSK-9 inhibitor group and 2,610 patients treated with statins-based lipid lowering therapies in statins-based group. The lipid control rate and incidence of major adverse cardiovascular events(MACE) over six months were compared between two groups.A propensity score-matched(PSM) analysis was used to balance two groups on confounding factors. Survival analysis using Kaplan-Meier methods was applied for MACE.RESULTS In a total of 3,063 patients, 89.91% of patients had received moderate or high-intensity statins-based therapy before PCI, but only 9.47% of patients had low-density lipoprotein cholesterol(LDL-C) levels below 1.4 mmol/L at baseline. In the PSM selected patients, LDL-C level was reduced by 42.57% in PCSK-9 inhibitor group and 30.81%(P < 0.001) in statins-based group after six months. The proportion of LDL-C ≤ 1.0 mmol/L increased from 5.29% to 29.26% in PCSK-9 inhibitor group and 0.23% to 6.11% in statins-based group, and the proportion of LDL-C ≤ 1.4 mmol/L increased from 10.36% to 47.69% in PCSK-9 inhibitor group and 2.99% to 18.43% in statins-based group(P < 0.001 for both). There was no significant difference between PCSK-9 inhibitor and statins-based treatment in reducing the risk of MACE(hazard ratio = 2.52, 95% CI: 0.49-12.97, P = 0.250).CONCLUSIONS In the real world, PCSK-9 inhibitors combined with statins could significantly reduce LDL-C levels among patients with very high risk of ASCVD in China. The long-term clinical benefits for patients received PCSK-9 inhibitor to reduce the risk of MACE is still unclear and requires further study.展开更多
The high pressure pneumatic system has been applied to special industries. It may cause errors when we analyze high pressure pneumatics under ideal gas assumption. However, the real gas effect on the performances of h...The high pressure pneumatic system has been applied to special industries. It may cause errors when we analyze high pressure pneumatics under ideal gas assumption. However, the real gas effect on the performances of high pressure pneumatics is seldom investigated. In this paper, the real gas effects on air enthalpy and internal energy are estimated firstly to study the real gas effect on the energy conversion. Under ideal gas assumption, enthalpy and internal energy are solely related to air temperature. The estimation result indicates that the pressure enthalpy and pressure internal energy of real pneumatic air obviously decrease the values of enthalpy and internal energy for high pressure pneumatics, and the values of pressure enthalpy and pressure internal energy are close. Based on the relationship among pressure, enthalpy and internal energy, the real gas effects on charging and discharging processes of high pressure pneumatics are estimated, which indicates that the real gas effect accelerates the temperature and pressure decreasing rates during discharging process, and decelerates their increasing rates during charging process. According to the above analysis, and for the inconvenience in building the simulation model for real gas and the difficulty of measuring the detail thermal capacities of pneumatics, a method to compensate the real gas effect under ideal gas assumption is proposed by modulating the thermal capacity of the pneumatic container in simulation. The experiments of switching expansion reduction (SER) for high pressure pneumatics are used to verify this compensating method. SER includes the discharging process of supply tanks and the charging process of expansion tank. The simulated and experimental results of SER are highly consistent. The proposed compensation method provides a convenient way to obtain more realistic simulation results for high pressure pneumatics.展开更多
Switching expansion reduction(SER)uses a switch valve instead of the throttle valve to realize electronically controlled pressure reduction for high pressure pneumatics.A comprehensive and interactive pneumatic simula...Switching expansion reduction(SER)uses a switch valve instead of the throttle valve to realize electronically controlled pressure reduction for high pressure pneumatics.A comprehensive and interactive pneumatic simulation model according to the experimental setup of SER has been built.The mathematical model considers heat exchanges,source air pressure and temperature,environmental temperatures and heat transfer coefficients variations.In addition,the compensation for real gas effect is used in the model building.The comparison between experiments and simulations of SER indicates that,to compensate the real gas effect in high pressure discharging process,the thermal capacity of air supply container in simulation should be less than the actual value.The higher the pressure range,the greater the deviation.Simulated and experimental results are highly consistent within pressure reduction ratios ranging from 1.4 to 20 and output air mass flow rates ranging from 3.5 to 132 g/s,which verifies the high adaptability of SER and the validity of the mathematic model and the compensation method.展开更多
In recent years, the Shanghai Institute of Organic Chemistry under the CAS has freed itself from the stereotyped rut of conventional forms in its external intercourse while still sticking fast to upholding its strateg...In recent years, the Shanghai Institute of Organic Chemistry under the CAS has freed itself from the stereotyped rut of conventional forms in its external intercourse while still sticking fast to upholding its strategic goal of disciplinary development. Our stress in this aspect has shifted to the pursuit of real effects and diversified forms in international S&T exchange. Our exploration features the following four characteristics:展开更多
This study investigates the valuation and real effects of the mandatory disclosure of greenhouse gas(GHG)emission costs from the perspective of“double materiality.”We consider a firm with a Cobb-Douglas production ...This study investigates the valuation and real effects of the mandatory disclosure of greenhouse gas(GHG)emission costs from the perspective of“double materiality.”We consider a firm with a Cobb-Douglas production function that combines GHG-related and non-GHG-related investments to produce short-term and long-term returns.In particular,the GHG-related investment entails short-term and long-term social costs of GHG emissions,including corporate costs and negative externalities.We demonstrate how the mandatory disclosure of the long-term costs of GHG emissions affects capital market valuations and corporate investment decisions relative to a non-disclosure regime.The social welfare in an accounting regime hinges on three parameters:the persistence of the short-term investment return,the ratio of the productivity of GHG-related investment to that of non-GHG-related investment,and the social cost parameter for GHG emissions.Our findings suggest that disclosing the long-term costs of GHG emissions may be detrimental to social welfare.Specifically,the non-disclosure regime results in higher social welfare than the disclosure regime for high values of these parameters.展开更多
This paper examines the Granger causal relationship between capital flows and economic growth in China over the period 1998Q1–2019Q2,allowing for real effective exchange rate(REER)effects.As parameter instability tes...This paper examines the Granger causal relationship between capital flows and economic growth in China over the period 1998Q1–2019Q2,allowing for real effective exchange rate(REER)effects.As parameter instability tests indicate structural changes,we use bootstrap rolling window causality tests,which suggest that the causal nexus between capital flows and GDP growth is time-varying.We find that the causal links between foreign direct investments(FDIs)and GDP growth are hardly affected by the REER,whereas the REER plays a more important role in affecting the causal connections between portfolio investments and other investments and GDP growth.Our results suggest that cumulative portfolio inflows and cumulative other investment inflows harm GDP growth,whereas cumulative portfolio outflows and cumula-tive other investment outflows positively affect GDP growth.展开更多
An important limitation of the research literatures which study the effect on the export of the real effective exchange rates is the lack of application of interaction or moderator effect among the independent variabl...An important limitation of the research literatures which study the effect on the export of the real effective exchange rates is the lack of application of interaction or moderator effect among the independent variables. To remedy this lacuna, the authors developed a model in which real effective exchange rate moderated the effect of import and utilization of foreign capital on export. The sample comprised 11 years' data in Guangdong China. The result showed that real effective exchange rate of RMB affected the export by interacting with utilization of foreign capital. Moreover, to some degree, the real effective exchange rate can also act as moderator between import and export.展开更多
Using data for the period 2000-2011, we construct province-level real effective exchange rate (REER) indices for China and test the effect of REER depreciation on regional economic growth in a generalized method of ...Using data for the period 2000-2011, we construct province-level real effective exchange rate (REER) indices for China and test the effect of REER depreciation on regional economic growth in a generalized method of moments regression framework. Our results show that REER depreciation, in general, promotes regional economic growth, through increasing net exports and lowering FDI costs. After dividing the full sample into coastal and inland subsamples, we find that REER depreciation influences economic growth in inland areas but not in coastal areas. This is due to the fact that the inland areas have more surplus labor or other resources to expand their production capacity when REER depreciation leads to increased worm demand. Furthermore, compared to inland areas, processing-and-assembly trade comprises a larger share of trade in the coastal areas, where traders import more raw materials and intermediate goods to process and assemble goods. When the exchange rate depreciates, the costs of imported materials and immediate goods increase. In this case, the benefits from REER depreciation in coastal areas are offset to some extent and are thus lower than in inland areas.展开更多
The regenerative refrigeration is an important reverse work-heat conversion cycle with a theoretical coefficient of performance(COP)identical to the Carnot efficiency.Practical regenerative refrigerators are capable o...The regenerative refrigeration is an important reverse work-heat conversion cycle with a theoretical coefficient of performance(COP)identical to the Carnot efficiency.Practical regenerative refrigerators are capable of working down to 4 K and largely fulfill the refrigeration requirement of modern technologies in many fields,especially for space applications.However,the enthalpy flow associated with the pressure dependence,abbreviated as pressure-induced enthalpy flow,brought about by real gas effects degrades the theoretical COP of the refrigerator to below about 30% of the Carnot efficiency at the temperatures of below the critical point.This paper reviews the long history of exploring the real gas effects which dates back to the 1970 s and continues to now.Important explorations of uncovering the loss mechanism and reducing such losses are summarized.The theories that are in accordance with experimental results and simulation results are expounded.We further carry out analyses on the expansion components,including the pulse tube and the clearance gap.Several inferences are made in order to explore the long-lasting puzzles about real gas effects.It is emphasized that the underlying cause of the loss in the regenerator is an indirect effect of the real gas properties.Further study about carrying out a direct verification of the theory is proposed.展开更多
This paper measures the industry-specific real effective exchange rate (REER) for China by matching domestic and foreign industry-level price and trade data series. We find that after 2005 the REER appreciates more ...This paper measures the industry-specific real effective exchange rate (REER) for China by matching domestic and foreign industry-level price and trade data series. We find that after 2005 the REER appreciates more in the "chemical, plastics, rubber and fuels industry" and the "'machinery and equipment industry," but remains roughly constant or even depreciates in other industries. The nominal exchange rate generally accounts for over 50 percent of the aggregate real effective exchange rate JTuetuations, but this conclusion does not apply to three of nine industries. We apply the industry-specific REER to re-examine the relationship between the exchange rate and trade, and find that the industry-specific REER index performs better than the traditional aggregate REER index. We recommend that the Chinese Government officially adopt industry-specific exchange rates instead of using the aggregate effective exchange rates to evaluate the competitiveness of Chinese industries in the international market.展开更多
In the press conference held by the News Office,theState Council on September 17,1993,Mr Hou Jie,Ministerof Construction,told Chinese and foreign journalists thatthe macro control measures put over the real estate had...In the press conference held by the News Office,theState Council on September 17,1993,Mr Hou Jie,Ministerof Construction,told Chinese and foreign journalists thatthe macro control measures put over the real estate hadtaken effect.He also welcomed friends from all over theworld to come and invest in real estate development inChina.When requested about the results of a series of meas-ures over real estate development,Mr Hou Jie said that展开更多
The sky-high house prices are nothing new in China, especially in metropolitan areas like Beijing, Shanghai and Shenzhen, where houses in prime locations can fetch prices as high as those in London, New York and Tokyo...The sky-high house prices are nothing new in China, especially in metropolitan areas like Beijing, Shanghai and Shenzhen, where houses in prime locations can fetch prices as high as those in London, New York and Tokyo. People with an average monthly salary of between $400 and $500, the group most affected, face enormous pressure, both psychologically and financially, when required to repay bank loans on their new home. This has led to a new relationship where home-展开更多
This paper examines how the China-bound exports of Japan and Korea are related to exchange rates, motivated by the fact that processing trade makes up a large proportion of China's trade, and that Japan and Korea are...This paper examines how the China-bound exports of Japan and Korea are related to exchange rates, motivated by the fact that processing trade makes up a large proportion of China's trade, and that Japan and Korea are the leading source countries for processing imports. Because processing imports are inputs for exports, the link between such imports and China's exchange rates are ambiguous. We estimate export functions that include China's RMB real effective exchauge rates (REER) along with bilateral real exchange rates (B RER) using Johausen 's cointegration method aud find that the RMB REER significantly affects Japanese and Korean exports to China, even more so than BRER in most cases examined. These two exchange rates appear in the export equations with opposite signs. Subsequently, we use the estimated model to illustrate the importance of accounting for a concurrent change in B RER when analyzing the effects of a hypothetical RMB revaluation on China's trade balances despite the apparently weak imports-B RER linkage.展开更多
The free piston shock tunnel is a type of shock tunnel with high performance. For this type of tunnel, the influence mechanism of shock wave attenuation on tailored operation is explored by numerical simulation and th...The free piston shock tunnel is a type of shock tunnel with high performance. For this type of tunnel, the influence mechanism of shock wave attenuation on tailored operation is explored by numerical simulation and theoretical analysis. By introducing the normalized velocity, the simple constraint equation for shock wave under the tailored operation is deduced. Moreover, the real gas effect is also taken into account in this equation. Based on the equation, the tailored operation of shock tunnels can be predicted with very few calculations. The present study shows that the change rate of the thermodynamic state of the gas behind the shock wave is inconsistent with the attenuation rate of the shock wave, which is the fundamental reason why the wind tunnel achieves tailored operation at a lower Mach number of shock waves. This lower Mach number of shock waves differs from the corresponding ideal value by a factor, which is about the square root of shock attenuation rate.展开更多
The mass flow rate measurement using a critical nozzle shows the validity of the inviscid theory, indicating that the discharge coefficient increases and approaches unity as the Reynolds number increases under the ide...The mass flow rate measurement using a critical nozzle shows the validity of the inviscid theory, indicating that the discharge coefficient increases and approaches unity as the Reynolds number increases under the ideal gas law However, when the critical nozzle measures the mass flow rate of a real gas such as hydrogen at a pressure of hundreds bar, the discharge coefficient exceeds unity, and the real gas effects should be taken into account. The present study aims at investigating the flow features of the critical nozzle using high-pressured hydrogen gas. The axisymmetric, compressible Navier-Stokes computation is employed to simulate the critical nozzle flow, and a fully implicit finite volume method is used to discretize the governing equation system. The real gas effects are simulated to consider the intermolecular forces, which account for the possibility of liquefying hydrogen gas. The computational results are compared with past experimental data. It has been found that the coefficient of discharge for real gas can be corrected properly below unity adopting the real gas assumption.展开更多
Based on the matched data of China’s tax survey and customs from 2007 to 2011,this paper studies the differential impact of exchange rate changes on the performance of companies by region from the perspective of fact...Based on the matched data of China’s tax survey and customs from 2007 to 2011,this paper studies the differential impact of exchange rate changes on the performance of companies by region from the perspective of factor market distortion.The results show that for import companies,the RMB appreciation significantly contributes to improving their performance and this phenomenon is more pronounced in areas with high factor market distortions.Channel tests show that the proportion of intermediate goods imported by final producers increases with regional factor market distortions.Therefore,the appreciation of the national currency is more favorable for areas with high factor market distortions(companies with high proportion of imported intermediate goods).In addition,the appreciation of the national currency will promote the production of China’s upstream intermediate goods producers by expanding the output of downstream enterprises.This paper complements previous studies on the differential impact of RMB exchange rate changes on regional economic growth from a micro perspective.展开更多
基金supported by the China Cardiovascular Health Alliance-Advanced Fund (2019CCA-ACCESS-054)the Beijing Lisheng Cardiovascular Health Foundation Pilot Fund Key Projects。
文摘BACKGROUND The efficacy and safety of proprotein convertase subtilisin/kexin type 9(PCSK-9) inhibitors were confirmed by several clinical trials, but its effectiveness in routine clinical practice in China has not been evaluated. This study aims to describe the real world effectiveness of PCSK-9 inhibitors combined with statins compared with statins-based therapy among patients with very high risk of atherosclerotic cardiovascular disease(ASCVD).METHODS This is a multi-center observational study, enrolled patients from 32 hospitals who underwent percutaneous coronary intervention(PCI) from January to June in 2019. There are 453 patients treated with PCSK-9 inhibitors combined with statins in PCSK-9 inhibitor group and 2,610 patients treated with statins-based lipid lowering therapies in statins-based group. The lipid control rate and incidence of major adverse cardiovascular events(MACE) over six months were compared between two groups.A propensity score-matched(PSM) analysis was used to balance two groups on confounding factors. Survival analysis using Kaplan-Meier methods was applied for MACE.RESULTS In a total of 3,063 patients, 89.91% of patients had received moderate or high-intensity statins-based therapy before PCI, but only 9.47% of patients had low-density lipoprotein cholesterol(LDL-C) levels below 1.4 mmol/L at baseline. In the PSM selected patients, LDL-C level was reduced by 42.57% in PCSK-9 inhibitor group and 30.81%(P < 0.001) in statins-based group after six months. The proportion of LDL-C ≤ 1.0 mmol/L increased from 5.29% to 29.26% in PCSK-9 inhibitor group and 0.23% to 6.11% in statins-based group, and the proportion of LDL-C ≤ 1.4 mmol/L increased from 10.36% to 47.69% in PCSK-9 inhibitor group and 2.99% to 18.43% in statins-based group(P < 0.001 for both). There was no significant difference between PCSK-9 inhibitor and statins-based treatment in reducing the risk of MACE(hazard ratio = 2.52, 95% CI: 0.49-12.97, P = 0.250).CONCLUSIONS In the real world, PCSK-9 inhibitors combined with statins could significantly reduce LDL-C levels among patients with very high risk of ASCVD in China. The long-term clinical benefits for patients received PCSK-9 inhibitor to reduce the risk of MACE is still unclear and requires further study.
基金supported by National Natural Science Foundation of China (Grant No. 50575202)
文摘The high pressure pneumatic system has been applied to special industries. It may cause errors when we analyze high pressure pneumatics under ideal gas assumption. However, the real gas effect on the performances of high pressure pneumatics is seldom investigated. In this paper, the real gas effects on air enthalpy and internal energy are estimated firstly to study the real gas effect on the energy conversion. Under ideal gas assumption, enthalpy and internal energy are solely related to air temperature. The estimation result indicates that the pressure enthalpy and pressure internal energy of real pneumatic air obviously decrease the values of enthalpy and internal energy for high pressure pneumatics, and the values of pressure enthalpy and pressure internal energy are close. Based on the relationship among pressure, enthalpy and internal energy, the real gas effects on charging and discharging processes of high pressure pneumatics are estimated, which indicates that the real gas effect accelerates the temperature and pressure decreasing rates during discharging process, and decelerates their increasing rates during charging process. According to the above analysis, and for the inconvenience in building the simulation model for real gas and the difficulty of measuring the detail thermal capacities of pneumatics, a method to compensate the real gas effect under ideal gas assumption is proposed by modulating the thermal capacity of the pneumatic container in simulation. The experiments of switching expansion reduction (SER) for high pressure pneumatics are used to verify this compensating method. SER includes the discharging process of supply tanks and the charging process of expansion tank. The simulated and experimental results of SER are highly consistent. The proposed compensation method provides a convenient way to obtain more realistic simulation results for high pressure pneumatics.
基金Project(51205421)supported by the National Natural Science Foundation of ChinaProject(2012M521647)supported by the Postdoctoral Science Foundation of China
文摘Switching expansion reduction(SER)uses a switch valve instead of the throttle valve to realize electronically controlled pressure reduction for high pressure pneumatics.A comprehensive and interactive pneumatic simulation model according to the experimental setup of SER has been built.The mathematical model considers heat exchanges,source air pressure and temperature,environmental temperatures and heat transfer coefficients variations.In addition,the compensation for real gas effect is used in the model building.The comparison between experiments and simulations of SER indicates that,to compensate the real gas effect in high pressure discharging process,the thermal capacity of air supply container in simulation should be less than the actual value.The higher the pressure range,the greater the deviation.Simulated and experimental results are highly consistent within pressure reduction ratios ranging from 1.4 to 20 and output air mass flow rates ranging from 3.5 to 132 g/s,which verifies the high adaptability of SER and the validity of the mathematic model and the compensation method.
文摘In recent years, the Shanghai Institute of Organic Chemistry under the CAS has freed itself from the stereotyped rut of conventional forms in its external intercourse while still sticking fast to upholding its strategic goal of disciplinary development. Our stress in this aspect has shifted to the pursuit of real effects and diversified forms in international S&T exchange. Our exploration features the following four characteristics:
文摘This study investigates the valuation and real effects of the mandatory disclosure of greenhouse gas(GHG)emission costs from the perspective of“double materiality.”We consider a firm with a Cobb-Douglas production function that combines GHG-related and non-GHG-related investments to produce short-term and long-term returns.In particular,the GHG-related investment entails short-term and long-term social costs of GHG emissions,including corporate costs and negative externalities.We demonstrate how the mandatory disclosure of the long-term costs of GHG emissions affects capital market valuations and corporate investment decisions relative to a non-disclosure regime.The social welfare in an accounting regime hinges on three parameters:the persistence of the short-term investment return,the ratio of the productivity of GHG-related investment to that of non-GHG-related investment,and the social cost parameter for GHG emissions.Our findings suggest that disclosing the long-term costs of GHG emissions may be detrimental to social welfare.Specifically,the non-disclosure regime results in higher social welfare than the disclosure regime for high values of these parameters.
文摘This paper examines the Granger causal relationship between capital flows and economic growth in China over the period 1998Q1–2019Q2,allowing for real effective exchange rate(REER)effects.As parameter instability tests indicate structural changes,we use bootstrap rolling window causality tests,which suggest that the causal nexus between capital flows and GDP growth is time-varying.We find that the causal links between foreign direct investments(FDIs)and GDP growth are hardly affected by the REER,whereas the REER plays a more important role in affecting the causal connections between portfolio investments and other investments and GDP growth.Our results suggest that cumulative portfolio inflows and cumulative other investment inflows harm GDP growth,whereas cumulative portfolio outflows and cumula-tive other investment outflows positively affect GDP growth.
文摘An important limitation of the research literatures which study the effect on the export of the real effective exchange rates is the lack of application of interaction or moderator effect among the independent variables. To remedy this lacuna, the authors developed a model in which real effective exchange rate moderated the effect of import and utilization of foreign capital on export. The sample comprised 11 years' data in Guangdong China. The result showed that real effective exchange rate of RMB affected the export by interacting with utilization of foreign capital. Moreover, to some degree, the real effective exchange rate can also act as moderator between import and export.
文摘Using data for the period 2000-2011, we construct province-level real effective exchange rate (REER) indices for China and test the effect of REER depreciation on regional economic growth in a generalized method of moments regression framework. Our results show that REER depreciation, in general, promotes regional economic growth, through increasing net exports and lowering FDI costs. After dividing the full sample into coastal and inland subsamples, we find that REER depreciation influences economic growth in inland areas but not in coastal areas. This is due to the fact that the inland areas have more surplus labor or other resources to expand their production capacity when REER depreciation leads to increased worm demand. Furthermore, compared to inland areas, processing-and-assembly trade comprises a larger share of trade in the coastal areas, where traders import more raw materials and intermediate goods to process and assemble goods. When the exchange rate depreciates, the costs of imported materials and immediate goods increase. In this case, the benefits from REER depreciation in coastal areas are offset to some extent and are thus lower than in inland areas.
基金supported by National Natural Science Foundation of China(No.51506152 and No.51777141)the Fundamental Research Funds for the Central Universities(inter-disciplinary program)under the contract No.kx0080020173427。
文摘The regenerative refrigeration is an important reverse work-heat conversion cycle with a theoretical coefficient of performance(COP)identical to the Carnot efficiency.Practical regenerative refrigerators are capable of working down to 4 K and largely fulfill the refrigeration requirement of modern technologies in many fields,especially for space applications.However,the enthalpy flow associated with the pressure dependence,abbreviated as pressure-induced enthalpy flow,brought about by real gas effects degrades the theoretical COP of the refrigerator to below about 30% of the Carnot efficiency at the temperatures of below the critical point.This paper reviews the long history of exploring the real gas effects which dates back to the 1970 s and continues to now.Important explorations of uncovering the loss mechanism and reducing such losses are summarized.The theories that are in accordance with experimental results and simulation results are expounded.We further carry out analyses on the expansion components,including the pulse tube and the clearance gap.Several inferences are made in order to explore the long-lasting puzzles about real gas effects.It is emphasized that the underlying cause of the loss in the regenerator is an indirect effect of the real gas properties.Further study about carrying out a direct verification of the theory is proposed.
基金supported by the Fundamental Research Funds for the Central Universities(No.2012WYB34)from Beijing Normal University
文摘This paper measures the industry-specific real effective exchange rate (REER) for China by matching domestic and foreign industry-level price and trade data series. We find that after 2005 the REER appreciates more in the "chemical, plastics, rubber and fuels industry" and the "'machinery and equipment industry," but remains roughly constant or even depreciates in other industries. The nominal exchange rate generally accounts for over 50 percent of the aggregate real effective exchange rate JTuetuations, but this conclusion does not apply to three of nine industries. We apply the industry-specific REER to re-examine the relationship between the exchange rate and trade, and find that the industry-specific REER index performs better than the traditional aggregate REER index. We recommend that the Chinese Government officially adopt industry-specific exchange rates instead of using the aggregate effective exchange rates to evaluate the competitiveness of Chinese industries in the international market.
基金the National Natural Science Foundation of China(No.51205421)the Fund of the Key Laboratory of Sensing Technology and Biomedical Instruments of Guangdong Province(No.2011A060901013)
文摘In the press conference held by the News Office,theState Council on September 17,1993,Mr Hou Jie,Ministerof Construction,told Chinese and foreign journalists thatthe macro control measures put over the real estate hadtaken effect.He also welcomed friends from all over theworld to come and invest in real estate development inChina.When requested about the results of a series of meas-ures over real estate development,Mr Hou Jie said that
文摘The sky-high house prices are nothing new in China, especially in metropolitan areas like Beijing, Shanghai and Shenzhen, where houses in prime locations can fetch prices as high as those in London, New York and Tokyo. People with an average monthly salary of between $400 and $500, the group most affected, face enormous pressure, both psychologically and financially, when required to repay bank loans on their new home. This has led to a new relationship where home-
基金financially supported by the research fund of Chungnam National University
文摘This paper examines how the China-bound exports of Japan and Korea are related to exchange rates, motivated by the fact that processing trade makes up a large proportion of China's trade, and that Japan and Korea are the leading source countries for processing imports. Because processing imports are inputs for exports, the link between such imports and China's exchange rates are ambiguous. We estimate export functions that include China's RMB real effective exchauge rates (REER) along with bilateral real exchange rates (B RER) using Johausen 's cointegration method aud find that the RMB REER significantly affects Japanese and Korean exports to China, even more so than BRER in most cases examined. These two exchange rates appear in the export equations with opposite signs. Subsequently, we use the estimated model to illustrate the importance of accounting for a concurrent change in B RER when analyzing the effects of a hypothetical RMB revaluation on China's trade balances despite the apparently weak imports-B RER linkage.
基金supported by the National Natural Science Foundation of China (No. 11572303)。
文摘The free piston shock tunnel is a type of shock tunnel with high performance. For this type of tunnel, the influence mechanism of shock wave attenuation on tailored operation is explored by numerical simulation and theoretical analysis. By introducing the normalized velocity, the simple constraint equation for shock wave under the tailored operation is deduced. Moreover, the real gas effect is also taken into account in this equation. Based on the equation, the tailored operation of shock tunnels can be predicted with very few calculations. The present study shows that the change rate of the thermodynamic state of the gas behind the shock wave is inconsistent with the attenuation rate of the shock wave, which is the fundamental reason why the wind tunnel achieves tailored operation at a lower Mach number of shock waves. This lower Mach number of shock waves differs from the corresponding ideal value by a factor, which is about the square root of shock attenuation rate.
文摘The mass flow rate measurement using a critical nozzle shows the validity of the inviscid theory, indicating that the discharge coefficient increases and approaches unity as the Reynolds number increases under the ideal gas law However, when the critical nozzle measures the mass flow rate of a real gas such as hydrogen at a pressure of hundreds bar, the discharge coefficient exceeds unity, and the real gas effects should be taken into account. The present study aims at investigating the flow features of the critical nozzle using high-pressured hydrogen gas. The axisymmetric, compressible Navier-Stokes computation is employed to simulate the critical nozzle flow, and a fully implicit finite volume method is used to discretize the governing equation system. The real gas effects are simulated to consider the intermolecular forces, which account for the possibility of liquefying hydrogen gas. The computational results are compared with past experimental data. It has been found that the coefficient of discharge for real gas can be corrected properly below unity adopting the real gas assumption.
文摘Based on the matched data of China’s tax survey and customs from 2007 to 2011,this paper studies the differential impact of exchange rate changes on the performance of companies by region from the perspective of factor market distortion.The results show that for import companies,the RMB appreciation significantly contributes to improving their performance and this phenomenon is more pronounced in areas with high factor market distortions.Channel tests show that the proportion of intermediate goods imported by final producers increases with regional factor market distortions.Therefore,the appreciation of the national currency is more favorable for areas with high factor market distortions(companies with high proportion of imported intermediate goods).In addition,the appreciation of the national currency will promote the production of China’s upstream intermediate goods producers by expanding the output of downstream enterprises.This paper complements previous studies on the differential impact of RMB exchange rate changes on regional economic growth from a micro perspective.