The central air conditioning system in an intelligent building (IB) was analyzed and modeled in order to perform the optimization scheduling strategy of the central air conditioning system. A set of models proposed ...The central air conditioning system in an intelligent building (IB) was analyzed and modeled in order to perform the optimization scheduling strategy of the central air conditioning system. A set of models proposed and a type of periodically autoregressive model (PAR) based on the improved genetic algorithms (IGA) were used to perform the optimum energy saving scheduling. The example of the Liangmahe Plaza was taken to show the effectiveness of the methods.展开更多
A water loop variable refrigerant flow（WLVRF）air-conditioning system is designed to be applied in large-scale buildings in northern China.The system is energy saving and it is an integrated system consisting of a va...A water loop variable refrigerant flow（WLVRF）air-conditioning system is designed to be applied in large-scale buildings in northern China.The system is energy saving and it is an integrated system consisting of a variable refrigerant flow（VRF）air-conditioning unit,a water loop and an air source heat pump.The water loop transports energy among different regions in the buildings instead of refrigerant pipes,decreasing the scale of the VRF air-conditioning unit and improving the performance.Previous models for refrigerants and building loads are cited in this investigation.Mathematical models of major equipment and other elements of the system are established using the lumped parameter method based on the DATAFIT software and the MATLAB software.The performance of the WLVRF system is simulated.The initial investments and the running costs are calculated based on the results of market research.Finally,a contrast is carried out between the WLVRF system and the traditional VRF system.The results show that the WLVRF system has a better working condition and lower running costs than the traditional VRF system.展开更多
In this paper, we prove the existence in H＋^2, an incomplete metric subspace of H^2×H^2×H^2, of global solutions to the system for a one-dimensional non-monotone fluid in bounded domainΩ=（0,1）. The resul...In this paper, we prove the existence in H＋^2, an incomplete metric subspace of H^2×H^2×H^2, of global solutions to the system for a one-dimensional non-monotone fluid in bounded domainΩ=（0,1）. The results in this paper have improved those previously related results.展开更多
An aircraft cabin is a narrow,closed-space environment.To keep the air quality in cabin healthy for passengers,especially during an epidemic such as SARS-CoV-2(or 2019-nCoV)in 2020,a novel aircraft air conditioning sy...An aircraft cabin is a narrow,closed-space environment.To keep the air quality in cabin healthy for passengers,especially during an epidemic such as SARS-CoV-2(or 2019-nCoV)in 2020,a novel aircraft air conditioning system,called the ultra-high-temperature instantaneous sterilization air conditioning system(UHTACS),is proposed.Based on the proposed system,a simulation of the UHT-ACS is analysed in various flight states.In the UHT-ACS,the mixing air temperature of return and bleed air can reach temperature up to 148.8°C,which is high enough to kill bacilli and viruses in 2一8 s.The supply air temperature of the UHT-ACS in a mixing cavity is about 12 C in cooling mode both on the ground and in the air.The supply air temperature is about 42 C in heating mode.Compared with the air conditioning systems(ACS)of traditional aircraft the supply air temperatures of the UHT-ACS in the mixing cavity are in good agreement with those of a traditional ACS with 60%fresh air and 40%return air.Furthermore the air temperature at the turbine outlet of the UHT-ACS is higher than that of a traditional ACS which will help to reduce the risk of icing at the outlet.Therefore the UHT-ACS can operate normally in various flight states.展开更多
Abstract： In this paper, we propose a mecha- nism for multicast data transmission in IEEE 802.16 mesh networks aimed at increasing the throughput by incorporating mini-slot spatial reuse. The proposed mechanism inclu...Abstract： In this paper, we propose a mecha- nism for multicast data transmission in IEEE 802.16 mesh networks aimed at increasing the throughput by incorporating mini-slot spatial reuse. The proposed mechanism includes two novel algorithms： a source-based multicast tree topology construction algorithm followed by an interference-aware multieast scheduling algorithm. The proposed multicast interfer- ence-aware scheduling algorithm can be ap- plied to both source-based and rendez- vous-based multicast tree topologies. Results of our simulation study show that in compari- son to the mechanism used for the IEEE 802.16＇s standard, the proposed multicast tree generation algorithm reduces the number of consumed mini-slots by 64% on average. Moreover, using the proposed interfer- ence-aware scheduling algorithm decreases the number of required mini-slots by a further 22% on average. Therefore, the proposed mul- ticast scheduling mechanism shows a higher throughput than the previous approaches and it is more scalable with respect to increasing the number of multicast groups as well as in- creasing the number of members inside each multicast group.展开更多
Refrigerant is a medium used in refrigeration cycle. Until now in thermodynamic models calculations of refrigerant is not considered with lubricant and moist air but as an ideal pure gas （without any contaminants）. ...Refrigerant is a medium used in refrigeration cycle. Until now in thermodynamic models calculations of refrigerant is not considered with lubricant and moist air but as an ideal pure gas （without any contaminants）. This is also the case in refrigeration cycle where the refrigerant is very often considered as an ideal one. Lubricant, air and water vapour are not considered in thermodynamic calculations in spite of their existence. The problems in the existing research are summarized. A further study is suggested on refrigerant systems. This circulation of such calculations is at the origin of a deviation from a theoretical behaviour. This article aims at reviewing the researches of oil-refrigerant, air-refrigerant, moist air-refrigerant or oil-moist air-refrigerant mixtures and focuses particularly on mixture enthalpy calculation. This paper deals with the description of the real mixture of refrigerant and contaminants （lubricant, water, moist air and other remains of refrigerants at elevated pressures and temperatures） which flow in a refrigerating cycle and the main point of this paper is to appoint thermodynamic parameters of such a mixture using the thermodynamic formulas.展开更多
In order to make maximum use of the EV （electric vehicle） battery, evaluating the remaining battery capacity and the power consumption is important. Evaluation method of the remaining battery capacity with accuracy ...In order to make maximum use of the EV （electric vehicle） battery, evaluating the remaining battery capacity and the power consumption is important. Evaluation method of the remaining battery capacity with accuracy has been proposed. Moreover, the evaluation method of the power consumption for traveling has been proposed. However, the power consumption for vehicle-mounted air-conditioner is 30%. It is necessary to calculate the power consumption for both traveling and air-conditioning. In this paper, the authors have constructed a mathematical model which calculates the EV power consumption for both traveling and air-conditioning. The calculated results of this model have been compared to actual traveling data. In addition, factors which have a impact on the EV power consumption have been studied. As a result, the EV power consumption is greately varied by slope resistance, acceleration resistance and required air-conditioning load. Moreover, it is clarified that the air-conditioner consumes approximately 25% to 50% of the total power consumption in a hot summer day. In addition, the acceleration and the air-conditioning load differ depending on each vehicle driver. Therefore, in order to evaluate the EV power consumption practically, it is necessary to reflect the characteristics of each vehicle driver.展开更多
With the development of manned spaceflight, more and more researches are involved in the area of gravitation physiology. When astronauts are exposed to microgravity, a series of special physiological or pathological c...With the development of manned spaceflight, more and more researches are involved in the area of gravitation physiology. When astronauts are exposed to microgravity, a series of special physiological or pathological changes will occur, which will start self-regulation mechanisms to reduce abnormalities and help the organism to better adapt to microgravity. However, these adaptive changes may also induce degradation or damage to physiological functions. This paper summarizes the physiological effects of microgravity on the human body from the aspects of skeletal and mineral metabolism, muscle structure and function, vestibular functions, cardiovascular function and pulmonary function, as well as expounds some commonly used ground-based space analogies. The paper will provide a reference for further study on the physiological effects of microgravity.展开更多
文摘The central air conditioning system in an intelligent building (IB) was analyzed and modeled in order to perform the optimization scheduling strategy of the central air conditioning system. A set of models proposed and a type of periodically autoregressive model (PAR) based on the improved genetic algorithms (IGA) were used to perform the optimum energy saving scheduling. The example of the Liangmahe Plaza was taken to show the effectiveness of the methods.
文摘A water loop variable refrigerant flow（WLVRF）air-conditioning system is designed to be applied in large-scale buildings in northern China.The system is energy saving and it is an integrated system consisting of a variable refrigerant flow（VRF）air-conditioning unit,a water loop and an air source heat pump.The water loop transports energy among different regions in the buildings instead of refrigerant pipes,decreasing the scale of the VRF air-conditioning unit and improving the performance.Previous models for refrigerants and building loads are cited in this investigation.Mathematical models of major equipment and other elements of the system are established using the lumped parameter method based on the DATAFIT software and the MATLAB software.The performance of the WLVRF system is simulated.The initial investments and the running costs are calculated based on the results of market research.Finally,a contrast is carried out between the WLVRF system and the traditional VRF system.The results show that the WLVRF system has a better working condition and lower running costs than the traditional VRF system.
文摘In this paper, we prove the existence in H＋^2, an incomplete metric subspace of H^2×H^2×H^2, of global solutions to the system for a one-dimensional non-monotone fluid in bounded domainΩ=（0,1）. The results in this paper have improved those previously related results.
基金the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)and the Foundation of Jiangsu Postdoctoral(No.2019K126)。
文摘An aircraft cabin is a narrow,closed-space environment.To keep the air quality in cabin healthy for passengers,especially during an epidemic such as SARS-CoV-2(or 2019-nCoV)in 2020,a novel aircraft air conditioning system,called the ultra-high-temperature instantaneous sterilization air conditioning system(UHTACS),is proposed.Based on the proposed system,a simulation of the UHT-ACS is analysed in various flight states.In the UHT-ACS,the mixing air temperature of return and bleed air can reach temperature up to 148.8°C,which is high enough to kill bacilli and viruses in 2一8 s.The supply air temperature of the UHT-ACS in a mixing cavity is about 12 C in cooling mode both on the ground and in the air.The supply air temperature is about 42 C in heating mode.Compared with the air conditioning systems(ACS)of traditional aircraft the supply air temperatures of the UHT-ACS in the mixing cavity are in good agreement with those of a traditional ACS with 60%fresh air and 40%return air.Furthermore the air temperature at the turbine outlet of the UHT-ACS is higher than that of a traditional ACS which will help to reduce the risk of icing at the outlet.Therefore the UHT-ACS can operate normally in various flight states.
文摘Abstract： In this paper, we propose a mecha- nism for multicast data transmission in IEEE 802.16 mesh networks aimed at increasing the throughput by incorporating mini-slot spatial reuse. The proposed mechanism includes two novel algorithms： a source-based multicast tree topology construction algorithm followed by an interference-aware multieast scheduling algorithm. The proposed multicast interfer- ence-aware scheduling algorithm can be ap- plied to both source-based and rendez- vous-based multicast tree topologies. Results of our simulation study show that in compari- son to the mechanism used for the IEEE 802.16＇s standard, the proposed multicast tree generation algorithm reduces the number of consumed mini-slots by 64% on average. Moreover, using the proposed interfer- ence-aware scheduling algorithm decreases the number of required mini-slots by a further 22% on average. Therefore, the proposed mul- ticast scheduling mechanism shows a higher throughput than the previous approaches and it is more scalable with respect to increasing the number of multicast groups as well as in- creasing the number of members inside each multicast group.
文摘Refrigerant is a medium used in refrigeration cycle. Until now in thermodynamic models calculations of refrigerant is not considered with lubricant and moist air but as an ideal pure gas （without any contaminants）. This is also the case in refrigeration cycle where the refrigerant is very often considered as an ideal one. Lubricant, air and water vapour are not considered in thermodynamic calculations in spite of their existence. The problems in the existing research are summarized. A further study is suggested on refrigerant systems. This circulation of such calculations is at the origin of a deviation from a theoretical behaviour. This article aims at reviewing the researches of oil-refrigerant, air-refrigerant, moist air-refrigerant or oil-moist air-refrigerant mixtures and focuses particularly on mixture enthalpy calculation. This paper deals with the description of the real mixture of refrigerant and contaminants （lubricant, water, moist air and other remains of refrigerants at elevated pressures and temperatures） which flow in a refrigerating cycle and the main point of this paper is to appoint thermodynamic parameters of such a mixture using the thermodynamic formulas.
文摘In order to make maximum use of the EV （electric vehicle） battery, evaluating the remaining battery capacity and the power consumption is important. Evaluation method of the remaining battery capacity with accuracy has been proposed. Moreover, the evaluation method of the power consumption for traveling has been proposed. However, the power consumption for vehicle-mounted air-conditioner is 30%. It is necessary to calculate the power consumption for both traveling and air-conditioning. In this paper, the authors have constructed a mathematical model which calculates the EV power consumption for both traveling and air-conditioning. The calculated results of this model have been compared to actual traveling data. In addition, factors which have a impact on the EV power consumption have been studied. As a result, the EV power consumption is greately varied by slope resistance, acceleration resistance and required air-conditioning load. Moreover, it is clarified that the air-conditioner consumes approximately 25% to 50% of the total power consumption in a hot summer day. In addition, the acceleration and the air-conditioning load differ depending on each vehicle driver. Therefore, in order to evaluate the EV power consumption practically, it is necessary to reflect the characteristics of each vehicle driver.
文摘With the development of manned spaceflight, more and more researches are involved in the area of gravitation physiology. When astronauts are exposed to microgravity, a series of special physiological or pathological changes will occur, which will start self-regulation mechanisms to reduce abnormalities and help the organism to better adapt to microgravity. However, these adaptive changes may also induce degradation or damage to physiological functions. This paper summarizes the physiological effects of microgravity on the human body from the aspects of skeletal and mineral metabolism, muscle structure and function, vestibular functions, cardiovascular function and pulmonary function, as well as expounds some commonly used ground-based space analogies. The paper will provide a reference for further study on the physiological effects of microgravity.
