Based on non-commercial forests in Kunming City,this article conducts survey of 506 households in Kunming City to evaluate their willingness to pay ecological benefit of non-commercial forests,using Contingent Valuati...Based on non-commercial forests in Kunming City,this article conducts survey of 506 households in Kunming City to evaluate their willingness to pay ecological benefit of non-commercial forests,using Contingent Valuation Method(CVM);to analyze factors influencing their willingness to compensate for non-commercial forests,using multivariate statistical analysis method.The results show that income,educational level, housing ownership,outdoor exercise time,whether to be concerned about environmental problems,frequency of obtaining forest-related information monthly and whether understanding non-commercial forests or not,are the most principal factors influencing willingness to pay.展开更多
The forest ecological compensation is an important factor to balance the interests of different areas for sustainable development and environment protection. Mudanjiang City in Heilongjiang Province of China is rich o...The forest ecological compensation is an important factor to balance the interests of different areas for sustainable development and environment protection. Mudanjiang City in Heilongjiang Province of China is rich of forest resources. The forestry coverage rate reached 62.3% in 2014, after forestry conservation program from 2002. The authors explored the factors impacted on forest ecological compensation in Mudanjiang City, which was a demonstration as a case study, through experts' evaluation scores and AHP methodology to analyze the forest ecological compensation factors and lay the foundation for the establishment of ecological compensation mechanism. At the same time, we provided an example to explore the effective way and speed up the establishment of ecological compensation mechanism. The study found that the main factors that determined forest ecological compensation in Mudanjiang City were ecology and natural resources. Based on the analyses, some suggestions were put forward to promote the mechanism in a sustainable way.展开更多
In order to minimize the harmonic distortion rate of the current at the common coupling point,this paper proposes a coordinated allocation strategy of harmonic compensation capacity considering the performance of acti...In order to minimize the harmonic distortion rate of the current at the common coupling point,this paper proposes a coordinated allocation strategy of harmonic compensation capacity considering the performance of active power filters(APF).On the premise of proportional distribution of harmonic compensation capacity,the harmonic compensation rate of each APF is considered,and the harmonic current value of each APF to be compensated is obtained.At the same time,the communication topology is introduced.Each APF takes into account the compensation ability of other APFs.Finally,three APFs with different capacity and performance are configured at the harmonic source to suppress the same harmonic source,and the harmonic distortion rate is reduced to 1.73%.The simulation results show that the strategy can effectively improve the compensation capability of the multiple APF cascaded system to the power grid without increasing the installed capacity.展开更多
When wind farms,which is based on double fed induction generator(DFIG),are connected to the series compensation power system,the phenomenon of sub-synchronous oscillation(SSO)may occur.In order to study the sub-synchr...When wind farms,which is based on double fed induction generator(DFIG),are connected to the series compensation power system,the phenomenon of sub-synchronous oscillation(SSO)may occur.In order to study the sub-synchronous oscillation in wind power connected to series compensated power system and its influencing factors,we used RT-LAB to establish a simulation model concerning wind power connected to series-compensation power system.This model take a wind power connected to series compensation power system in north China as prototype.All influence factors of wind power SSO are simulated and analyzed by using time domain analysis method.The simulation results show that the effects of wind speed,series compensation degree and proportional control coefficient of rotor side converter(RSC)are most obvious.展开更多
Combined with the parameters of the production process of a steel factory, numerical simulations for a new ladle from preheating to turnover are conducted using the finite element analysis system software (ANSYS). T...Combined with the parameters of the production process of a steel factory, numerical simulations for a new ladle from preheating to turnover are conducted using the finite element analysis system software (ANSYS). The measured data proved that the simulated results are reliable. The effects of preheating time, thermal cycling times, and empty package time on steel temperature are calculated, an ideal preheating time is provided, besides, based on the analysis of a single factor and use the nonlinear analysis method, a steel temperature compensating model with di- versified coupling factors is proposed, with the largest error of the present coupling model at 1. 462 ~C, and the er- rors between actual and target steel temperature in tundish after the model is applied to practical production are basi- cally controlled within -4-6 ~C, which can meet the accuracy of the manufacturer and has a practical guiding significance for the production in steelmaking workshops.展开更多
A 40 Gb/s high speed optical transmission system is designed, and the different dispersion compensation schemes are adopted to realize the transmission of the optical duo-binary (ODB) signals over 120 km optical fiber...A 40 Gb/s high speed optical transmission system is designed, and the different dispersion compensation schemes are adopted to realize the transmission of the optical duo-binary (ODB) signals over 120 km optical fiber. Optical duo-binary signals are generated by using a precoder, two low- pass filters (LPF) and one mach-zehnder modulator (MZM). Through combination of dispersion compensation fiber (DCF) and single mode fiber (SMF) in the transmission link, four different dispersion compensation schemes (pre-compensation, post-compensation and hybrid compensation (pre+ post) and hybrid compensation (post+ pre)) were compared. Analyzing Q factor, BER, eye diagrams and receiver sensitivity in several dispersion compensation schemes, the simulation results are: the cut-off frequency of LPF affects the transmission performance, and the hybrid compensation (post+ pre) scheme is the optimal dispersion compensation method.展开更多
Many industrial installations in developing countries start-up as small factories, without regard for the need of compensation of reactive power, leading to significant financial losses in the long term. By improving ...Many industrial installations in developing countries start-up as small factories, without regard for the need of compensation of reactive power, leading to significant financial losses in the long term. By improving the power factor, the customer can reduce its power demand and potentially increase efficiency of their equipment. A PIC microcontroller is used to switch capacitor banks to compensate for the reactive power. In order to determine the size of the capacitor bank needed, the microcontroller calculates the phase difference between the voltage and the current. The results obtained based on the lagging power factor for three test loads show an improvement in the power factor from 0.52 to 0.96 under different test load conditions.展开更多
The paper introduces one design idea that making use of SCM to control Real-timely the dynamic compensation of reactive power.Firstly,design one Circuit to Sample the voltage and current,and by these datas we can easi...The paper introduces one design idea that making use of SCM to control Real-timely the dynamic compensation of reactive power.Firstly,design one Circuit to Sample the voltage and current,and by these datas we can easily calculate the power factor,and Voltage controller in the microcontroller to determine whether input the compensation capacitance according to the size of power factor,the paper also analyzes the principle of capacitance compensation and calculation method. Dynamic compensation for the entire process is quick and accurate.展开更多
Compliance,as a very important aspect of corporate governance,has developed earlier in the world,while China's compliance management has developed relatively late and is currently lacking in development.However,ma...Compliance,as a very important aspect of corporate governance,has developed earlier in the world,while China's compliance management has developed relatively late and is currently lacking in development.However,many enterprises suffer serious losses without compliance management,especially import and export enterprises,which are forced to exit the market due to poor compliance management.This article is based on the urgent need of Chinese enterprises for compliance management,but the lack of research by scholars.It summarizes the literature on the factors affecting compliance,hoping to be helpful for the study of compliance management.展开更多
Post-earthquake building reconstruction usually faces challenges such as inadequate preparation and lack of resources,while compensation measures can help alleviate these difficulties.Although various compensation mea...Post-earthquake building reconstruction usually faces challenges such as inadequate preparation and lack of resources,while compensation measures can help alleviate these difficulties.Although various compensation measures have been proposed for accelerating post-earthquake recovery,their effects on building reconstruction are still unclear.This study aimed to analyze and evaluate the effects of compensation measures on post-earthquake building reconstruction.To achieve this objective,this study first identified the post-earthquake building reconstruction goals,21 reconstruction factors across five categories,and four compensation measures,and employed the methods of structural equation modeling,paired-samples t-test,and repeated measures analysis of variance to analyze the effects of reconstruction factors on the reconstruction goals and the effects of compensation measures on the reconstruction factors,respectively.A questionnaire was designed to investigate the post-earthquake building reconstruction projects in China,with 251 respondents participated.The results show that apart from project-specific condition,the other four categories of reconstruction factors,including owner condition,technology condition,resource availability,and contractor management capability,have significant effects on the reconstruction goals.The study also evaluated the extent of the above effects.On the other hand,the results indicate that the affecting extents of various compensation measures on reconstruction factors are significantly different.These findings can provide support and guidance for government management of post-earthquake building reconstruction and the development of compensation measures.They also provide a basis for future research on optimizing compensation measures for post-earthquake building reconstruction.展开更多
Modified mathematical models based on imaginary plane zone method in reheating furnace were developed in which non-gray radiation properties of gas were considered,and the Newton's method and the finite difference me...Modified mathematical models based on imaginary plane zone method in reheating furnace were developed in which non-gray radiation properties of gas were considered,and the Newton's method and the finite difference method were adopted. Effects of productivity,fuel consumption,fuel-air ratio,calorific value of fuel and inserting depth of thermocouple on total heat exchange factor along the length of reheating furnace were investigated. The results show that total heat exchange factor increases with productivity or inserting depth of thermocouple,and it decreases when fuel consumption,fuel-air ratio or calorific value of fuel increases. The results are valuable for dynamical compensation of total heat exchange factor for online control mathematical models in reheating furnace.展开更多
A parameter that allows an evaluation of power quality transmitted, or distributed, between energy source and the final user is electric system power factor. Among other aspects, a bigger power factor, close to unit v...A parameter that allows an evaluation of power quality transmitted, or distributed, between energy source and the final user is electric system power factor. Among other aspects, a bigger power factor, close to unit value, relieves operational conditions of lines and cables, besides, it improves feeder's voltage behavior. Due to load variation along the day, the dynamic compensation of power factor allows maintaining this parameter close to the ideal. This paper brings a study about a reactive dynamic compensator based on the voltage control in a capacitive element, varying the reactive energy in accordance with the system demand, everything from the energy efficiency point of view. In distribution systems, the losses due to this variable compensation can be lower than in other compensation methods and also the voltage presents a better behavior, justifying its application.展开更多
基金Supported by the Project of Yunnan Provincial Department of Scienceand Technology(110705)
文摘Based on non-commercial forests in Kunming City,this article conducts survey of 506 households in Kunming City to evaluate their willingness to pay ecological benefit of non-commercial forests,using Contingent Valuation Method(CVM);to analyze factors influencing their willingness to compensate for non-commercial forests,using multivariate statistical analysis method.The results show that income,educational level, housing ownership,outdoor exercise time,whether to be concerned about environmental problems,frequency of obtaining forest-related information monthly and whether understanding non-commercial forests or not,are the most principal factors influencing willingness to pay.
基金Supported by by the National Social Science(14BGL090)Humanities and Social Science Project of Educational Department in Heilongjiang Province(12542019)
文摘The forest ecological compensation is an important factor to balance the interests of different areas for sustainable development and environment protection. Mudanjiang City in Heilongjiang Province of China is rich of forest resources. The forestry coverage rate reached 62.3% in 2014, after forestry conservation program from 2002. The authors explored the factors impacted on forest ecological compensation in Mudanjiang City, which was a demonstration as a case study, through experts' evaluation scores and AHP methodology to analyze the forest ecological compensation factors and lay the foundation for the establishment of ecological compensation mechanism. At the same time, we provided an example to explore the effective way and speed up the establishment of ecological compensation mechanism. The study found that the main factors that determined forest ecological compensation in Mudanjiang City were ecology and natural resources. Based on the analyses, some suggestions were put forward to promote the mechanism in a sustainable way.
基金This work was supported in part by the National Natural Science Foundation of China(Grant No.61863023).
文摘In order to minimize the harmonic distortion rate of the current at the common coupling point,this paper proposes a coordinated allocation strategy of harmonic compensation capacity considering the performance of active power filters(APF).On the premise of proportional distribution of harmonic compensation capacity,the harmonic compensation rate of each APF is considered,and the harmonic current value of each APF to be compensated is obtained.At the same time,the communication topology is introduced.Each APF takes into account the compensation ability of other APFs.Finally,three APFs with different capacity and performance are configured at the harmonic source to suppress the same harmonic source,and the harmonic distortion rate is reduced to 1.73%.The simulation results show that the strategy can effectively improve the compensation capability of the multiple APF cascaded system to the power grid without increasing the installed capacity.
基金This work was supported by a grant from the science-technology program of China State Grid Corp“Research on the operation and control characteristics when the power sent out through series compensation from large new energy base”(No.52010116000S)。
文摘When wind farms,which is based on double fed induction generator(DFIG),are connected to the series compensation power system,the phenomenon of sub-synchronous oscillation(SSO)may occur.In order to study the sub-synchronous oscillation in wind power connected to series compensated power system and its influencing factors,we used RT-LAB to establish a simulation model concerning wind power connected to series-compensation power system.This model take a wind power connected to series compensation power system in north China as prototype.All influence factors of wind power SSO are simulated and analyzed by using time domain analysis method.The simulation results show that the effects of wind speed,series compensation degree and proportional control coefficient of rotor side converter(RSC)are most obvious.
基金Item Sponsored by Technology Supporting Program During the 11th Five-Year Plan Period(BAE03A07)
文摘Combined with the parameters of the production process of a steel factory, numerical simulations for a new ladle from preheating to turnover are conducted using the finite element analysis system software (ANSYS). The measured data proved that the simulated results are reliable. The effects of preheating time, thermal cycling times, and empty package time on steel temperature are calculated, an ideal preheating time is provided, besides, based on the analysis of a single factor and use the nonlinear analysis method, a steel temperature compensating model with di- versified coupling factors is proposed, with the largest error of the present coupling model at 1. 462 ~C, and the er- rors between actual and target steel temperature in tundish after the model is applied to practical production are basi- cally controlled within -4-6 ~C, which can meet the accuracy of the manufacturer and has a practical guiding significance for the production in steelmaking workshops.
文摘A 40 Gb/s high speed optical transmission system is designed, and the different dispersion compensation schemes are adopted to realize the transmission of the optical duo-binary (ODB) signals over 120 km optical fiber. Optical duo-binary signals are generated by using a precoder, two low- pass filters (LPF) and one mach-zehnder modulator (MZM). Through combination of dispersion compensation fiber (DCF) and single mode fiber (SMF) in the transmission link, four different dispersion compensation schemes (pre-compensation, post-compensation and hybrid compensation (pre+ post) and hybrid compensation (post+ pre)) were compared. Analyzing Q factor, BER, eye diagrams and receiver sensitivity in several dispersion compensation schemes, the simulation results are: the cut-off frequency of LPF affects the transmission performance, and the hybrid compensation (post+ pre) scheme is the optimal dispersion compensation method.
文摘Many industrial installations in developing countries start-up as small factories, without regard for the need of compensation of reactive power, leading to significant financial losses in the long term. By improving the power factor, the customer can reduce its power demand and potentially increase efficiency of their equipment. A PIC microcontroller is used to switch capacitor banks to compensate for the reactive power. In order to determine the size of the capacitor bank needed, the microcontroller calculates the phase difference between the voltage and the current. The results obtained based on the lagging power factor for three test loads show an improvement in the power factor from 0.52 to 0.96 under different test load conditions.
文摘The paper introduces one design idea that making use of SCM to control Real-timely the dynamic compensation of reactive power.Firstly,design one Circuit to Sample the voltage and current,and by these datas we can easily calculate the power factor,and Voltage controller in the microcontroller to determine whether input the compensation capacitance according to the size of power factor,the paper also analyzes the principle of capacitance compensation and calculation method. Dynamic compensation for the entire process is quick and accurate.
文摘Compliance,as a very important aspect of corporate governance,has developed earlier in the world,while China's compliance management has developed relatively late and is currently lacking in development.However,many enterprises suffer serious losses without compliance management,especially import and export enterprises,which are forced to exit the market due to poor compliance management.This article is based on the urgent need of Chinese enterprises for compliance management,but the lack of research by scholars.It summarizes the literature on the factors affecting compliance,hoping to be helpful for the study of compliance management.
基金supported by the National Natural Science Foundation of China(NSFC)(Grant No.72204280)the Research and Innovation Team Support Program Funding Project of Central University of Finance and Economics(CUFE)(Grant No.CUFE-2021-GG-1)The authors are thankful for the support of NSFC and CUFE.
文摘Post-earthquake building reconstruction usually faces challenges such as inadequate preparation and lack of resources,while compensation measures can help alleviate these difficulties.Although various compensation measures have been proposed for accelerating post-earthquake recovery,their effects on building reconstruction are still unclear.This study aimed to analyze and evaluate the effects of compensation measures on post-earthquake building reconstruction.To achieve this objective,this study first identified the post-earthquake building reconstruction goals,21 reconstruction factors across five categories,and four compensation measures,and employed the methods of structural equation modeling,paired-samples t-test,and repeated measures analysis of variance to analyze the effects of reconstruction factors on the reconstruction goals and the effects of compensation measures on the reconstruction factors,respectively.A questionnaire was designed to investigate the post-earthquake building reconstruction projects in China,with 251 respondents participated.The results show that apart from project-specific condition,the other four categories of reconstruction factors,including owner condition,technology condition,resource availability,and contractor management capability,have significant effects on the reconstruction goals.The study also evaluated the extent of the above effects.On the other hand,the results indicate that the affecting extents of various compensation measures on reconstruction factors are significantly different.These findings can provide support and guidance for government management of post-earthquake building reconstruction and the development of compensation measures.They also provide a basis for future research on optimizing compensation measures for post-earthquake building reconstruction.
基金Sponsored by National Basic Research Program of China (2006CB601203)
文摘Modified mathematical models based on imaginary plane zone method in reheating furnace were developed in which non-gray radiation properties of gas were considered,and the Newton's method and the finite difference method were adopted. Effects of productivity,fuel consumption,fuel-air ratio,calorific value of fuel and inserting depth of thermocouple on total heat exchange factor along the length of reheating furnace were investigated. The results show that total heat exchange factor increases with productivity or inserting depth of thermocouple,and it decreases when fuel consumption,fuel-air ratio or calorific value of fuel increases. The results are valuable for dynamical compensation of total heat exchange factor for online control mathematical models in reheating furnace.
文摘A parameter that allows an evaluation of power quality transmitted, or distributed, between energy source and the final user is electric system power factor. Among other aspects, a bigger power factor, close to unit value, relieves operational conditions of lines and cables, besides, it improves feeder's voltage behavior. Due to load variation along the day, the dynamic compensation of power factor allows maintaining this parameter close to the ideal. This paper brings a study about a reactive dynamic compensator based on the voltage control in a capacitive element, varying the reactive energy in accordance with the system demand, everything from the energy efficiency point of view. In distribution systems, the losses due to this variable compensation can be lower than in other compensation methods and also the voltage presents a better behavior, justifying its application.