The present study focuses on the formulation of new composite consisting of plaster and raffia vinifera particle (RVP) with the purpose to reducing energy consumption. The aim of this study is to test this new compoun...The present study focuses on the formulation of new composite consisting of plaster and raffia vinifera particle (RVP) with the purpose to reducing energy consumption. The aim of this study is to test this new compound as an insulating eco-material in building in a tropical climate. The composites samples were developed by mixing plaster with raffia vinifera particles (RVP) using three different sizes (1.6 mm, 2.5 mm and 4 mm). The effects of four different RVP incorporations rates (i.e., 0wt%, 5wt%;10wt%;15wt%) on physical, thermal, mechanicals properties of the composites were investigated. In addition, the use of the raffia vinifera particles and plaster based composite material as building envelopes thermal insulation material is studied by the habitable cell thermal behavior instrumentation. The results indicate that the incorporation of raffia vinifera particle leads to improve the new composite physical, mechanical and thermal properties. And the parametric analysis reveals that the sampling rate and the size of raffia vinifera particles are the most decisive factor to impact these properties, and to decreases in the thermal conductivity which leads to an improvement to the thermal resistance and energy savings. The best improvement of plaster composite was obtained at the raffia vinifera particles size between 2.5 and 4.0 mm loading of 5wt% (C95P5R) with a good ratio of thermo-physical-mechanical properties. Additionally, the habitable cell experimental thermal behavior, with the new raffia vinifera particles and plaster-based composite as thermal insulating material for building walls, gives an average damping of 4°C and 5.8°C in the insulated house interior environment respectively for cold and hot cases compared to the outside environment and the uninsulated house interior environment. The current study highlights that this mixture gives the new composite thermal insulation properties applicable in the eco-construction of habitats in tropical environments.展开更多
In order to study the indoor thermal environments in university classrooms in Tianjin,a field study and a questionnaire survey for a main teaching building are carried out.First,the thermal sensations of participants ...In order to study the indoor thermal environments in university classrooms in Tianjin,a field study and a questionnaire survey for a main teaching building are carried out.First,the thermal sensations of participants in the typical classrooms are studied by 180 questionnaires.Then,based on the measured data,the temperature changes in the classrooms during a year are simulated by the DeST software.The results show that the indoor thermal environments in the northern classrooms on the first floor are better than those in other classrooms.And the measurement results accord with the simulation results.These results can be used as a reference for the study of the indoor thermal environments in other seasons.展开更多
To explore the thermal responses under the non-thermal equilibrium cold environmental conditions,a laboratory study was conducted in climate chamber.The local skin temperatures and thermal sensation of 20 subjects wer...To explore the thermal responses under the non-thermal equilibrium cold environmental conditions,a laboratory study was conducted in climate chamber.The local skin temperatures and thermal sensation of 20 subjects were recorded at 10 min intervals for 90 min under air temperatures of 7.4,9.1,11 and 15 °C.The results show that both local skin temperatures and mean skin temperature decrease not only with the drop of ambient air temperature but also with the exposure time.Local thermal sensation and overall the thermal sensation have the similar temperature-varying and time-varying characteristics.Predicted mean vote(PMV) model cannot correctly predict the thermal sensation under non-thermal equilibrium cold environment.The correlation between local thermal sensation and local skin temperatures shows that thermal sensation is closely related to skin temperature.Skin temperature is an effective indicator of thermal sensation.A linear relationship model between overall thermal sensation and mean skin temperature,considering both ambient temperature and exposure time,was established in the non-thermal equilibrium cold environment,which makes the evaluation of thermal sensation more objective.展开更多
Low Resolution Thermal Array Sensors are widely used in several applications in indoor environments. In particular, one of these cheap, small and unobtrusive sensors provides a low-resolution thermal image of the envi...Low Resolution Thermal Array Sensors are widely used in several applications in indoor environments. In particular, one of these cheap, small and unobtrusive sensors provides a low-resolution thermal image of the environment and, unlike cameras;it is capable to detect human heat emission even in dark rooms. The obtained thermal data can be used to monitor older seniors while they are performing daily activities at home, to detect critical situations such as falls. Most of the studies in activity recognition using Thermal Array Sensors require human detection techniques to recognize humans passing in the sensor field of view. This paper aims to improve the accuracy of the algorithms used so far by considering the temperature environment variation. This method leverages an adaptive background estimation and a noise removal technique based on Kalman Filter. In order to properly validate the system, a novel installation of a single sensor has been implemented in a smart environment: the obtained results show an improvement in human detection accuracy with respect to the state of the art, especially in case of disturbed environments.展开更多
To analyze the thermal comfort and indoor air quality (IAQ) in a medium-sized mechanically ventilated gymnasium in Beijing,a field study was carried out. PHOENICS,one of the CFD software,was chosen to simulate the dis...To analyze the thermal comfort and indoor air quality (IAQ) in a medium-sized mechanically ventilated gymnasium in Beijing,a field study was carried out. PHOENICS,one of the CFD software,was chosen to simulate the distribution of the indicators of indoor air in the gymnasium to check the air-conditioning parameters reasonable or not. And there was a questionnaire for audiences and staff about the acceptance and satisfaction of the thermal comfort,simultaneously,some environmental parameters were monitored. Then an experiment was carried out in gymnasium with the plate sedimentation to the biological aerosol in the air. Finally,the thermal comfort and IAQ in the gymnasium were assessed based on the results of above questionnaire survey and measurements. The results show that most parameters of the environmental are within the standard limits of thermal comfort and IAQ in the monitored period,and the biological contaminants initially come from human beings. The main species in the gymnasium are streptobacillus,coccus,cladosporium,penicillium and neurospora.展开更多
With the living standards gradually improved,the buildings with safe,comfortable,healthy indoor thermal environment would be the ideal pursuit. But to create the preferable indoor thermal environment,it is necessary t...With the living standards gradually improved,the buildings with safe,comfortable,healthy indoor thermal environment would be the ideal pursuit. But to create the preferable indoor thermal environment,it is necessary to research physiological influence of indoor thermal environment on human body. So a typical region of hot-humid climate in Chongqing,China,was considered as the object to study physiological indexes of human body. And the indoor thermal environment parameters and physiological indexes of human body were the main measurements. 20 volunteer students were organized to take part in the experiments in the laboratory during this summer. And two methods,physical measuring and questionnaire investigation,were used in the experiments. The results show that the increase in indoor air temperature reduces the uncomfortable feeling of air draft. Indoor air temperature has visible effects on MCS (motor nerve conduction speed),SCS (sensory nerve conduction speed),HR (heart rate),the ECG (electrocardiogram)-QT segment and SSEP (short somatosensory evoked potential)-latent period of N9. Therefore,a safe,comfortable and healthful indoor environment can be created by considering these factors.展开更多
For the rural housing in Yanbian region in winter,the indoor thermal environment is bad but the energy consumption is high.And in order to solve the problem,the life particularities of the local residents,such as the ...For the rural housing in Yanbian region in winter,the indoor thermal environment is bad but the energy consumption is high.And in order to solve the problem,the life particularities of the local residents,such as the inhabitation custom and the different living ways,were analyzed.The comfortable temperature felt by the local residents was surveyed and summarized according to different age's stage.The subjective comfortable temperature was calculated by using the thermal comfort formula set up by D.A.Mcintyre.The result shows that the comfortable temperature between the survey and the calculation is different.After analyzing the survey and the result calculations,the range of local indoor comfortable temperature was given,which provides a reference basis for calculating the thermal comfort and energy efficiency as well as designing green rural houses.展开更多
In order to implement the optimal design of the indoor thermal comfort based on the numerical modeling method, the numerical calculation platform is combined seamlessly with the data-processing platform, and an intera...In order to implement the optimal design of the indoor thermal comfort based on the numerical modeling method, the numerical calculation platform is combined seamlessly with the data-processing platform, and an interactive numerical calculation platform which includes the functions of numerical simulation and optimization is established. The artificial neural network (ANN) and the greedy strategy are introduced into the hill-climbing pattern heuristic search process, and the optimizing search direction can be predicted by using small samples; when searching along the direction using the greedy strategy, the optimal values can be quickly approached. Therefore, excessive external calling of the numerical modeling process can be avoided, and the optimization time is decreased obviously. The experimental results indicate that the satisfied output parameters of air conditioning can be quickly given out based on the interactive numerical calculation platform and the improved search method, and the optimization for indoor thermal comfort can be completed.展开更多
There are a large number of wooden-plank wall dwellings, a kind of traditional house with regional characteristics, existing in Chongqing area. We chose a typical house in Chongqing as the subject and measured it duri...There are a large number of wooden-plank wall dwellings, a kind of traditional house with regional characteristics, existing in Chongqing area. We chose a typical house in Chongqing as the subject and measured it during summer to research the situation of the indoor thermal comfort of wooden-plank wall dwellings. Based on the particularity of local residents' living habit and the characteristics of the local buildings, we analyzed the data of the field measurement and evaluated the thermal environment with APMV. The results show that the indoor thermal comfort of wooden-plank wall dwellings in summer is improved mainly by natural ventilation.展开更多
Latvian children under the age of 7 can spend up to 60 hours per week in daycare centers and therefore it is very important to establish a healthy and comfortable daycare environment that children will find pleasant a...Latvian children under the age of 7 can spend up to 60 hours per week in daycare centers and therefore it is very important to establish a healthy and comfortable daycare environment that children will find pleasant and stimulating to stay in. This study investigates indoor air quality and thermal comfort within six daycare centers (old, renovated and new-built) in moderate climate zone of Latvia. Measurements of carbon dioxide, air temperature and relative humidity were carried out, and data regarding daycare center characteristics and maintenance activities was collected via combination of field visits, record analysis and interviews. It was found that carbon dioxide concentrations exceeded 1000 ppm in 75% of daycare centers studied, with the highest (1356 ppm) measured in a renovated facility with the natural ventilation system. Thus installation of more efficient ventilation system (mechanical) is recommended to provide acceptable indoor air quality, since opening of windows itself cannot provide the optimal conditions indoors. In all facilities the temperature was kept above 20℃ and the average relative humidity was 40±35%, creating comfortable thermal environment for children.展开更多
文摘The present study focuses on the formulation of new composite consisting of plaster and raffia vinifera particle (RVP) with the purpose to reducing energy consumption. The aim of this study is to test this new compound as an insulating eco-material in building in a tropical climate. The composites samples were developed by mixing plaster with raffia vinifera particles (RVP) using three different sizes (1.6 mm, 2.5 mm and 4 mm). The effects of four different RVP incorporations rates (i.e., 0wt%, 5wt%;10wt%;15wt%) on physical, thermal, mechanicals properties of the composites were investigated. In addition, the use of the raffia vinifera particles and plaster based composite material as building envelopes thermal insulation material is studied by the habitable cell thermal behavior instrumentation. The results indicate that the incorporation of raffia vinifera particle leads to improve the new composite physical, mechanical and thermal properties. And the parametric analysis reveals that the sampling rate and the size of raffia vinifera particles are the most decisive factor to impact these properties, and to decreases in the thermal conductivity which leads to an improvement to the thermal resistance and energy savings. The best improvement of plaster composite was obtained at the raffia vinifera particles size between 2.5 and 4.0 mm loading of 5wt% (C95P5R) with a good ratio of thermo-physical-mechanical properties. Additionally, the habitable cell experimental thermal behavior, with the new raffia vinifera particles and plaster-based composite as thermal insulating material for building walls, gives an average damping of 4°C and 5.8°C in the insulated house interior environment respectively for cold and hot cases compared to the outside environment and the uninsulated house interior environment. The current study highlights that this mixture gives the new composite thermal insulation properties applicable in the eco-construction of habitats in tropical environments.
文摘In order to study the indoor thermal environments in university classrooms in Tianjin,a field study and a questionnaire survey for a main teaching building are carried out.First,the thermal sensations of participants in the typical classrooms are studied by 180 questionnaires.Then,based on the measured data,the temperature changes in the classrooms during a year are simulated by the DeST software.The results show that the indoor thermal environments in the northern classrooms on the first floor are better than those in other classrooms.And the measurement results accord with the simulation results.These results can be used as a reference for the study of the indoor thermal environments in other seasons.
基金Project(50838009) supported by the National Natural Science Foundation of China
文摘To explore the thermal responses under the non-thermal equilibrium cold environmental conditions,a laboratory study was conducted in climate chamber.The local skin temperatures and thermal sensation of 20 subjects were recorded at 10 min intervals for 90 min under air temperatures of 7.4,9.1,11 and 15 °C.The results show that both local skin temperatures and mean skin temperature decrease not only with the drop of ambient air temperature but also with the exposure time.Local thermal sensation and overall the thermal sensation have the similar temperature-varying and time-varying characteristics.Predicted mean vote(PMV) model cannot correctly predict the thermal sensation under non-thermal equilibrium cold environment.The correlation between local thermal sensation and local skin temperatures shows that thermal sensation is closely related to skin temperature.Skin temperature is an effective indicator of thermal sensation.A linear relationship model between overall thermal sensation and mean skin temperature,considering both ambient temperature and exposure time,was established in the non-thermal equilibrium cold environment,which makes the evaluation of thermal sensation more objective.
文摘Low Resolution Thermal Array Sensors are widely used in several applications in indoor environments. In particular, one of these cheap, small and unobtrusive sensors provides a low-resolution thermal image of the environment and, unlike cameras;it is capable to detect human heat emission even in dark rooms. The obtained thermal data can be used to monitor older seniors while they are performing daily activities at home, to detect critical situations such as falls. Most of the studies in activity recognition using Thermal Array Sensors require human detection techniques to recognize humans passing in the sensor field of view. This paper aims to improve the accuracy of the algorithms used so far by considering the temperature environment variation. This method leverages an adaptive background estimation and a noise removal technique based on Kalman Filter. In order to properly validate the system, a novel installation of a single sensor has been implemented in a smart environment: the obtained results show an improvement in human detection accuracy with respect to the state of the art, especially in case of disturbed environments.
基金Project(2006BAJ02A10) supported by the National Key Technologies R & D Program of China
文摘To analyze the thermal comfort and indoor air quality (IAQ) in a medium-sized mechanically ventilated gymnasium in Beijing,a field study was carried out. PHOENICS,one of the CFD software,was chosen to simulate the distribution of the indicators of indoor air in the gymnasium to check the air-conditioning parameters reasonable or not. And there was a questionnaire for audiences and staff about the acceptance and satisfaction of the thermal comfort,simultaneously,some environmental parameters were monitored. Then an experiment was carried out in gymnasium with the plate sedimentation to the biological aerosol in the air. Finally,the thermal comfort and IAQ in the gymnasium were assessed based on the results of above questionnaire survey and measurements. The results show that most parameters of the environmental are within the standard limits of thermal comfort and IAQ in the monitored period,and the biological contaminants initially come from human beings. The main species in the gymnasium are streptobacillus,coccus,cladosporium,penicillium and neurospora.
基金Projects(50838009, 50678179) supported by the National Natural Science Foundation of ChinaProject(2006BAJ02A09) supported by the National Key Technologies R & D Program of China
文摘With the living standards gradually improved,the buildings with safe,comfortable,healthy indoor thermal environment would be the ideal pursuit. But to create the preferable indoor thermal environment,it is necessary to research physiological influence of indoor thermal environment on human body. So a typical region of hot-humid climate in Chongqing,China,was considered as the object to study physiological indexes of human body. And the indoor thermal environment parameters and physiological indexes of human body were the main measurements. 20 volunteer students were organized to take part in the experiments in the laboratory during this summer. And two methods,physical measuring and questionnaire investigation,were used in the experiments. The results show that the increase in indoor air temperature reduces the uncomfortable feeling of air draft. Indoor air temperature has visible effects on MCS (motor nerve conduction speed),SCS (sensory nerve conduction speed),HR (heart rate),the ECG (electrocardiogram)-QT segment and SSEP (short somatosensory evoked potential)-latent period of N9. Therefore,a safe,comfortable and healthful indoor environment can be created by considering these factors.
基金Supported by National Natural Science Foundation of China(50378023)
文摘For the rural housing in Yanbian region in winter,the indoor thermal environment is bad but the energy consumption is high.And in order to solve the problem,the life particularities of the local residents,such as the inhabitation custom and the different living ways,were analyzed.The comfortable temperature felt by the local residents was surveyed and summarized according to different age's stage.The subjective comfortable temperature was calculated by using the thermal comfort formula set up by D.A.Mcintyre.The result shows that the comfortable temperature between the survey and the calculation is different.After analyzing the survey and the result calculations,the range of local indoor comfortable temperature was given,which provides a reference basis for calculating the thermal comfort and energy efficiency as well as designing green rural houses.
基金Sponsored by the National Program"973"Project (2005CB623906)
文摘In order to implement the optimal design of the indoor thermal comfort based on the numerical modeling method, the numerical calculation platform is combined seamlessly with the data-processing platform, and an interactive numerical calculation platform which includes the functions of numerical simulation and optimization is established. The artificial neural network (ANN) and the greedy strategy are introduced into the hill-climbing pattern heuristic search process, and the optimizing search direction can be predicted by using small samples; when searching along the direction using the greedy strategy, the optimal values can be quickly approached. Therefore, excessive external calling of the numerical modeling process can be avoided, and the optimization time is decreased obviously. The experimental results indicate that the satisfied output parameters of air conditioning can be quickly given out based on the interactive numerical calculation platform and the improved search method, and the optimization for indoor thermal comfort can be completed.
基金Funded by National Key Technology Research and Development Program of the Ministry of Science and Technology of China During the“12th Five Year Plan”(2013BAJ11B04)Funding Project for fundamental and Frontier Science of the Chongqing Science&Technology Commission(cstc2014jcyj A90024)
文摘There are a large number of wooden-plank wall dwellings, a kind of traditional house with regional characteristics, existing in Chongqing area. We chose a typical house in Chongqing as the subject and measured it during summer to research the situation of the indoor thermal comfort of wooden-plank wall dwellings. Based on the particularity of local residents' living habit and the characteristics of the local buildings, we analyzed the data of the field measurement and evaluated the thermal environment with APMV. The results show that the indoor thermal comfort of wooden-plank wall dwellings in summer is improved mainly by natural ventilation.
文摘Latvian children under the age of 7 can spend up to 60 hours per week in daycare centers and therefore it is very important to establish a healthy and comfortable daycare environment that children will find pleasant and stimulating to stay in. This study investigates indoor air quality and thermal comfort within six daycare centers (old, renovated and new-built) in moderate climate zone of Latvia. Measurements of carbon dioxide, air temperature and relative humidity were carried out, and data regarding daycare center characteristics and maintenance activities was collected via combination of field visits, record analysis and interviews. It was found that carbon dioxide concentrations exceeded 1000 ppm in 75% of daycare centers studied, with the highest (1356 ppm) measured in a renovated facility with the natural ventilation system. Thus installation of more efficient ventilation system (mechanical) is recommended to provide acceptable indoor air quality, since opening of windows itself cannot provide the optimal conditions indoors. In all facilities the temperature was kept above 20℃ and the average relative humidity was 40±35%, creating comfortable thermal environment for children.