Presently,the environmental pollution problem,especially that of the small and medium-sized enterprises,has become a bottleneck restricting the high-quality development of China’s economy.It is imperative to accelera...Presently,the environmental pollution problem,especially that of the small and medium-sized enterprises,has become a bottleneck restricting the high-quality development of China’s economy.It is imperative to accelerate the construction of a collaborative governance system with multiple subject participation.The behavior modes of Environmental Non-governmental Organizations(ENGOs),a key player in environmental care,in collaborating with core enterprises to control pollution from small and medium-sized suppliers should be explored.Therefore,we constructed a collaborative governance system consisting of ENGOs,focal firms and small and medium-sized suppliers.Then a two-stage game model was established to analyze the strategies of the governance system.Specifically,we studied the collaborative green cooperation strategy and antagonistic pressure supervision strategy between ENGOs and focal firms,analyzed factors influencing the strategic choices of each subject,and gave the advantages of the cooperation strategies through further comparisons.The results showed that:Under the cooperation strategy,ENGOs provided knowledge of environmental protection to the focal firms,then both the audit efforts of focal firms and the environmental protection efforts of small and medium-sized suppliers were effectively improved.Since ENGOs could not fully obtain the pollution information of small and medium-sized suppliers or accurately trace it from their downstream focal firms,it was difficult to drive the supply chain’s endogenous governance by this external monitoring of ENGOs,making the effect of pressure supervision strategy limited.The effectiveness of green cooperation strategy was positively correlated with the knowledge absorption capacity of focal firms,the unit product revenue,and the focal firms'violation penalties for small and medium-sized suppliers.When ENGOs'violation penalties for small and medium-sized suppliers were higher,or the reputation loss of focal firms was higher,more unfavorable conditions of green cooperation strategy could be achieved.Accordingly,ENGOs should choose to cooperate with focal firms with strong knowledge absorption ability and high profit per product;focal firms should learn environmental protection knowledge to improve the screening standards and review capabilities,and promote the achievement of green cooperation strategy conditions by strengthening active information disclosure;the government should promote the collaboration between ENGOs and focal firms by issuing environmental guidelines.展开更多
Based on the characteristics of sewage from beauty salons,a simulation model of a small sewage source heat pump triple supply system that can be applied to such places is established to optimize the operating conditio...Based on the characteristics of sewage from beauty salons,a simulation model of a small sewage source heat pump triple supply system that can be applied to such places is established to optimize the operating conditions of the system.The results show that with the increase of sewage temperature and flow,the performance of the system also increases.In summer conditions,the system provides cooling,recovers waste heat and condensed heat from sewage,with a COP value of 8.97;in winter conditions,the system heats and produces hot water,with a COP value of 2.44;in transitional seasons,only hot water is produced.The COP value is 2.75.Compared with the traditional systems which refers to the air source heat pump and hot water boiler system currently used in beauty salons,this system can save energy by 50.9%.展开更多
Inertial piezoelectric actuators are widely applied in precision devices with simple structure and accurate movement.However,existing inertial piezoelectric actuators still face the challenges of rollback motion and b...Inertial piezoelectric actuators are widely applied in precision devices with simple structure and accurate movement.However,existing inertial piezoelectric actuators still face the challenges of rollback motion and bulky power supply.In this work,an alternate excitation strategy and a customized small power supply for a bimorph rotary piezoelectric actuator(BRPA)are proposed to solve the problems.The BRPA prototype is designed with a bipedal symmetrical structure,measuring 35 mm in height and 32 mm in diameter,which has a maximum rotation velocity of 0.247 rad/s and a resolution of 0.66μrad.Thanks to the bipedal symmetrical structure,the friction directions between the driving feet and the rotor can be coordinated to suppress the rollback.The rollback ratio is almost zero when the phase difference of the exciting signal is set as 180°.The customized power supply is designed and manufactured,whose size is 58 mm×56 mm×46 mm.It can output signals for the single step mode and the continuous mode,and they are adopted to excite BRPA to achieve a small stroke with one single step and a large stroke with continuous step,respectively.Then,an experimental system for optical fiber alignment is developed based on the BRPA and the customized small power supply,the experiment has verified the practicability of this work in the precision fields,especially in the miniaturized precision systems.展开更多
文摘Presently,the environmental pollution problem,especially that of the small and medium-sized enterprises,has become a bottleneck restricting the high-quality development of China’s economy.It is imperative to accelerate the construction of a collaborative governance system with multiple subject participation.The behavior modes of Environmental Non-governmental Organizations(ENGOs),a key player in environmental care,in collaborating with core enterprises to control pollution from small and medium-sized suppliers should be explored.Therefore,we constructed a collaborative governance system consisting of ENGOs,focal firms and small and medium-sized suppliers.Then a two-stage game model was established to analyze the strategies of the governance system.Specifically,we studied the collaborative green cooperation strategy and antagonistic pressure supervision strategy between ENGOs and focal firms,analyzed factors influencing the strategic choices of each subject,and gave the advantages of the cooperation strategies through further comparisons.The results showed that:Under the cooperation strategy,ENGOs provided knowledge of environmental protection to the focal firms,then both the audit efforts of focal firms and the environmental protection efforts of small and medium-sized suppliers were effectively improved.Since ENGOs could not fully obtain the pollution information of small and medium-sized suppliers or accurately trace it from their downstream focal firms,it was difficult to drive the supply chain’s endogenous governance by this external monitoring of ENGOs,making the effect of pressure supervision strategy limited.The effectiveness of green cooperation strategy was positively correlated with the knowledge absorption capacity of focal firms,the unit product revenue,and the focal firms'violation penalties for small and medium-sized suppliers.When ENGOs'violation penalties for small and medium-sized suppliers were higher,or the reputation loss of focal firms was higher,more unfavorable conditions of green cooperation strategy could be achieved.Accordingly,ENGOs should choose to cooperate with focal firms with strong knowledge absorption ability and high profit per product;focal firms should learn environmental protection knowledge to improve the screening standards and review capabilities,and promote the achievement of green cooperation strategy conditions by strengthening active information disclosure;the government should promote the collaboration between ENGOs and focal firms by issuing environmental guidelines.
基金the Science and Technology Program Project of the Ministry of Housing and Urban-Rural Development“Research on Indoor Thermal Environment Based on Zero Energy Building Technology in Hot Summer and Cold Winter Area”(2017-K1-014)Hubei Provincial Natural Fund Youth Fund“Technology and Evaluation of Multi-energy Complementary Energy Supply for Rural Residential Buildings in Hubei”(2017CFB311).
文摘Based on the characteristics of sewage from beauty salons,a simulation model of a small sewage source heat pump triple supply system that can be applied to such places is established to optimize the operating conditions of the system.The results show that with the increase of sewage temperature and flow,the performance of the system also increases.In summer conditions,the system provides cooling,recovers waste heat and condensed heat from sewage,with a COP value of 8.97;in winter conditions,the system heats and produces hot water,with a COP value of 2.44;in transitional seasons,only hot water is produced.The COP value is 2.75.Compared with the traditional systems which refers to the air source heat pump and hot water boiler system currently used in beauty salons,this system can save energy by 50.9%.
基金supported by the National Natural Science Foundation of China(Grant Nos.52105015 and 52225501)the China Postdoctoral Science Foundation(Grant No.2021M690830)the Postdoctoral Science Foundation of Heilongjiang Province,China(Grant No.LBH-Z21018)。
文摘Inertial piezoelectric actuators are widely applied in precision devices with simple structure and accurate movement.However,existing inertial piezoelectric actuators still face the challenges of rollback motion and bulky power supply.In this work,an alternate excitation strategy and a customized small power supply for a bimorph rotary piezoelectric actuator(BRPA)are proposed to solve the problems.The BRPA prototype is designed with a bipedal symmetrical structure,measuring 35 mm in height and 32 mm in diameter,which has a maximum rotation velocity of 0.247 rad/s and a resolution of 0.66μrad.Thanks to the bipedal symmetrical structure,the friction directions between the driving feet and the rotor can be coordinated to suppress the rollback.The rollback ratio is almost zero when the phase difference of the exciting signal is set as 180°.The customized power supply is designed and manufactured,whose size is 58 mm×56 mm×46 mm.It can output signals for the single step mode and the continuous mode,and they are adopted to excite BRPA to achieve a small stroke with one single step and a large stroke with continuous step,respectively.Then,an experimental system for optical fiber alignment is developed based on the BRPA and the customized small power supply,the experiment has verified the practicability of this work in the precision fields,especially in the miniaturized precision systems.
