An investigation on relationship between clothing pressure of men's suit and wearing comfort is conducted. With the pressure measurements at different parts of men's suit under normal standing posture and in m...An investigation on relationship between clothing pressure of men's suit and wearing comfort is conducted. With the pressure measurements at different parts of men's suit under normal standing posture and in motion, the objective assessment of the total comfort are related to the subjective ratings of clothing pressure. There is a common strong sensation of pressure on shoulder with normal standing posture, and a strong relationship between total comfort and clothing pressure in back armhole and the front of upper arm with posture in motion.展开更多
With the global promotion of LED lighting products, the health and safety of LED products has drawn wider attention. This paper systematically introduces the ergonomic evaluation (methods and indicators) svstem for ...With the global promotion of LED lighting products, the health and safety of LED products has drawn wider attention. This paper systematically introduces the ergonomic evaluation (methods and indicators) svstem for heahh and comfort which differs from the traditional manpowered physical detection, and sketches out the evaluation indicators and its industrialization prospect.展开更多
Skin seasitive difference of human body sections under clothing is the theoretic foundation of thermal insulation clothing design. By a new psychological & physical researching method, the subjective psychological pe...Skin seasitive difference of human body sections under clothing is the theoretic foundation of thermal insulation clothing design. By a new psychological & physical researching method, the subjective psychological perception of human body sections affected by the same cold stimulus are studied, and with Thurstone comparative judgement the main human body sections' cold sensitivity sequences are obtained. Furthermore the physiological causes for skin sensitive difference of human body sections under clothing are suggested.展开更多
The local skin temperatures of 22 subjects at air temperatures of 21,24,26,29 ℃ are measured,and the mean skin temperatures are calculated by ten skin temperature measuring points.The thermal comfort levels and the t...The local skin temperatures of 22 subjects at air temperatures of 21,24,26,29 ℃ are measured,and the mean skin temperatures are calculated by ten skin temperature measuring points.The thermal comfort levels and the thermal sensations of these subjects are also investigated by a questionnaire.The Mahalanobis distance discrimination method is applied to establish the evaluation model for the thermal comfort based on the mean skin temperature.The experimental results indicate that the difference of the mean skin temperatures between the comfort level and the discomfort level is significant.Using the evaluation model,the mean skin temperature at the thermal comfort level is 32.6 to 33.7 ℃,and the thermal comfort levels of 72% of the subjects are correctly evaluated.The accuracy of the evaluation model can be improved when the effects of sex of the subject on the mean skin temperature and the thermal comfort are considered.It can be concluded that the mean skin temperature can be used as an effective physiological indicator to evaluate human thermal comfort in a steady thermal environment.展开更多
This paper introduces a field measurement of an indoor thermal environment in rural housing in suburban Beijing from December 2008 to March 2009.The indoor environment parameters such as air temperature,mean radiant t...This paper introduces a field measurement of an indoor thermal environment in rural housing in suburban Beijing from December 2008 to March 2009.The indoor environment parameters such as air temperature,mean radiant temperature(MRT),airflow velocity and relative humidity are measured.A questionnaire survey of the occupants' thermal sensations in these surveyed houses is conducted and their daily activities and clothing conditions are recorded.The results show that the thermal neutral temperature of rural housing is 18.4 ℃,and the lower limit of acceptable temperature range can be extended to 10.9 ℃.The comfortable indoor temperature is affected by the occupants' clothing and lifestyle.Therefore,the indoor temperature standards of space heating for suburban housing cannot be simply duplicated from that for urban housing.Compared with occupants in suburban Beijing,it is found that the occupants in rural Hunan province feel colder at the same operative temperature due to the high relative humidity in Hunan province.展开更多
To improve the accuracy of skin temperature measurements in thermal comfort research,a new measurement method based on a new thermometer is proposed.A platinum film resistance(Pt1000)sensor of the thermometer is wel...To improve the accuracy of skin temperature measurements in thermal comfort research,a new measurement method based on a new thermometer is proposed.A platinum film resistance(Pt1000)sensor of the thermometer is welded on a printed circuit board to eliminate the heat loss from the leads and avoid the influence of the surrounding thermal environment.In order to determine the suitable thickness of the board,a steady heat conduction model is established.The simulation results reveal that when the thickness of the board is 0.2 mm,the influence of the surrounding air can be effectively prevented and the skin temperature does not obviously increase.The experimental results of verification show that the maximum measurement error of the skin temperature measured by the thermometer is 0.24 ℃,and the average measurement error of the skin temperature is 0.04 ℃.The proposed method provides an effective and reliable option for the skin temperature measurement in thermal comfort research.展开更多
The human-induced vertical vibration serviceability of low-frequency and lightweight footbridges is studied based on the moving mass-spring-damper(MMSD) biodynamic model, and the mass damper(TMD) with different op...The human-induced vertical vibration serviceability of low-frequency and lightweight footbridges is studied based on the moving mass-spring-damper(MMSD) biodynamic model, and the mass damper(TMD) with different optimal model parameters being used to control the vertical vibration.First, the MMSD biodynamic model is employed to simulate the pedestrians, and the time-varying control equations of the vertical dynamic coupling system of the pedestrian-bridgeTMD are established with the consideration of pedestrianbridge dynamic interaction; and the equations are solved by using the Runge-Kutta-Felhberg integral method with variable step size. Secondly, the footbridge dynamic response is calculated under the model of pedestrian-structure dynamic interaction and the model of moving load when the pedestrian pace frequency is consistent with the natural frequency of footbridge. Finally, a comparative study and analysis are made on the control effects of the vertical dynamic coupling system in different optimal models of the TMD. The calculation results show that the pedestrian-bridge dynamic interaction cannot be ignored when the vertical human-induced vibration serviceability of low-frequency and light-weight footbridge is evaluated. The TMD can effectively reduce the vibration under the resonance of pedestrian-bridge, and TMD parameters are recommended for the determination by the Warburton optimization model.展开更多
Field measurements on thermal comfort were carried out in a building with double-skin faade from January 14th to 16th,2009.Data are obtained by measurements of physical parameters and a questionnaire survey is conduct...Field measurements on thermal comfort were carried out in a building with double-skin faade from January 14th to 16th,2009.Data are obtained by measurements of physical parameters and a questionnaire survey is conducted at the same time in 27 offices of the building.The subjective survey involves questions on demographic information of the occupants,health status,environmental comfort conditions and acceptance.A total of 150 occupants are investigated and 131 questionnaires are completed.The statistical data presents the distributions of predicted mean vote,mean thermal sensation vote,mean thermal comfort vote,thermal acceptability,etc.The results show that low relative humidity is the main reason causing thermal discomfort.The greatest discomfort is dry mouth and eye dryness which are caused by low relative humidity.The females are verified to be more sensitive than the males.Meanwhile,a double-skin faade represents a good noise insulation effect while the glare problem is still unresolved.展开更多
A new ground source heat pump system combined with radiant heating/cooling is proposed, and the principles and the advantages of the system are analyzed. A demonstration of the system is applied to a rebuilt building...A new ground source heat pump system combined with radiant heating/cooling is proposed, and the principles and the advantages of the system are analyzed. A demonstration of the system is applied to a rebuilt building: Xijindu exhibition hall, which is located in Zhenjiang city in China. Numerical studies on the thermal comfort and energy consumption of the system are carded out by using TRNSYS software. The results indicate that the system with the radiant floor method or the radiant ceiling method shows good thermal comfort without mechanical ventilation in winter. However, the system with either of the methods should add mechanical ventilation to ensure good comfort in summer. At the same level of thermal comfort, it can also be found that the annual energy consumption of the radiant ceiling system is less than that of the radiant floor system.展开更多
A systematic and effective optimization is proposed for the design of a three-dimensional (3-D) vehicle suspension model with eight degrees of freedom (DOF), including vertical seat motion, vehicle suspension, pit...A systematic and effective optimization is proposed for the design of a three-dimensional (3-D) vehicle suspension model with eight degrees of freedom (DOF), including vertical seat motion, vehicle suspension, pitching and rolling motions, and vertical wheel motions using the evolutionary game theory. A new design of the passive suspension is aided by game theory to attain the best compromise between ride quality and suspension deflections. Extensive simulations are performed on three type road surface models A, B, C pavement grades based on the guidelines provided by ISO-2631 with the Matlab/Simulink environment. The preliminary results show that, when the passive suspension is optimized via the proposed approach, a substantial improvement in the vertical ride quality is obtained while keeping the suspension deflections within their allowable clearance when the vehicle moves at a constant velocity v=20 m/s, and the comfort performance of a suspension seat can be enhanced by 20%-30%.展开更多
To study the draft sensation distribution of an air jet supply system in a large space building in summer,experiments are conducted in a large laboratory.The temperature,velocity and draft sensation distributions at a...To study the draft sensation distribution of an air jet supply system in a large space building in summer,experiments are conducted in a large laboratory.The temperature,velocity and draft sensation distributions at a nozzle height of 4 m in the occupied zone are obtained.Then,the numerical simulation under the test condition is carried out by the computational fluid dynamics(CFD)method.The calculation results of the indoor vertical temperature and the draft sensation distribution are validated by the test data.Simulations with different nozzle heights are conducted.The satisfactory air supply condition is determined by analyzing the draft sensations and the temperatures in the occupied zone under three conditions.The simulation results show that the optimal draft sensation distribution and the uniform temperature and velocity fields can be obtained at a nozzle height of 5 m.展开更多
Based on the meteorological data of 12 weather stations in the east section of silk road from 1971 to 2005, such as average monthly temperature, relative humidity, wind speed and sunshine duration, its climatic touris...Based on the meteorological data of 12 weather stations in the east section of silk road from 1971 to 2005, such as average monthly temperature, relative humidity, wind speed and sunshine duration, its climatic tourism comfort was analyzed by adopting temperature-humidity index, wind-chill index and index of cloth. The results showed that the most comfortable month for travelling in this region is May and September. From east to west, the climatic comfort of such a section is decreasing. The most suitable tourism season is summer, followed by autumn and spring, the least suitable season is winter.展开更多
While many harmful algal blooms have been associated with increasing eutrophication, not all species respond similarly and the increasing challenge, especially for resource managers, is to determine which blooms are r...While many harmful algal blooms have been associated with increasing eutrophication, not all species respond similarly and the increasing challenge, especially for resource managers, is to determine which blooms are related to eutrophication and to understand why particular species proliferate under specific nutrient conditions. The overall goal of this brief review is to describe why nutrient loads are not changing in stoichiometric proportion to the "Redfield ratio", and why this has important consequences for algal growth. Many types of harmful algae appear to be able to thrive, and/or increase their production of toxins, when nutrient loads are not in proportion classically identified as Redfield ratios. Here we also describe some of the physiological mechanisms of different species to take up nutrients and to thrive under conditions of nutrient imbalance.展开更多
Vehicle suspension design includes a number of compromises to provide good leveling of stability and ride comfort. Optimization of off-road vehicle suspension system is one of the most effective methods, which could c...Vehicle suspension design includes a number of compromises to provide good leveling of stability and ride comfort. Optimization of off-road vehicle suspension system is one of the most effective methods, which could considerably enhance the vehicle stability and controllability. In this work, a comprehensive optimization of an off-read vehicle suspension system model was carried out using software ADAMS. The geometric parameters of suspension system were optimized using genetic algorithm (GA) in a way that ride comfort, handling and stability of vehicle were improved. The results of optimized suspension system and variations of geometric parameters due to road roughness and different steering angles were presented in ADAMS and the results of optimized and conventional suspension systems during various driving maneuvers were compared. The simulation results indicate that the camber angle variations decrease by the optimized suspension system, resulting in improved handling and ride comfort characteristics.展开更多
AIM:To demonstrate the value of Diosmin(flavonidic fraction)in the management of post-haemorhoidectomic symptoms.METHODS:Eighty-six consecutive patients with grades ⅢandⅣacute mixed hemorrhoids admitted to the Anore...AIM:To demonstrate the value of Diosmin(flavonidic fraction)in the management of post-haemorhoidectomic symptoms.METHODS:Eighty-six consecutive patients with grades ⅢandⅣacute mixed hemorrhoids admitted to the Anorectal Surgical Department of First Affiliated Hospital,Xinjiang Medical University from April 2009 to April 2010,were enrolled in this study.An observerblinded,randomized trial was conducted to compare post-haemorhoidectomic symptoms with use of Diosmin flavonidic fraction vs placebo.Eighty-six patients were randomly allocated to receive Diosmin flavonidic fraction 500 mg for 1 wk(n=43)or placebo(n=43).The Milligan-Morgan open haemorrhoidectomy was performed by a standardized diathermy excision method.Pain,bleeding,heaviness,pruritus,wound edema and mucosal discharge were observed after surgery.The postoperative symptoms and hospitalization time were recorded.RESULTS:The mean age of the Diosmin group and controls was 53.2 and 51.3 years,respectively.In Diosmin group,haemorrhoid piles were of the third degree in 33 patients and the fourth degree in 10;and in the control group,29 were of the third degree and 14 were of the fourth degree.There was no statistically significance in age,gender distribution,degree and number of excised haemorrhoid piles,and the mean duration of haemorrhoidal disease between the two groups.There was a statistically significant improvement in pain,heaviness,bleeding,pruritus from baseline to the 8th week after operation(P<0.05).Patients taking Diosmin had a shorter hospitalization stay after surgery(P< 0.05).There was also a significant improvement on the proctoscopic appearance(P<0.001).However,there was no statistical difference between the two groups in terms of wound mucosal discharge.Two patients experienced minor bleeding at the 8th week in Diosmin group,and underwent surgery.CONCLUSION:Diosmin is effective in alleviating postoperational symptoms of haemorrhoids.Therefore,it should be considered for the initial treatment after haemorrhoid surgery.However,further prospective randomized trials are needed to confirm the findings of this study.展开更多
An active pipe-embedded building envelope, which is an external wall or roof with pipes embedded inside, was presented. This structure may utilize the circulating water in the pipe to transfer heat or coolth inside di...An active pipe-embedded building envelope, which is an external wall or roof with pipes embedded inside, was presented. This structure may utilize the circulating water in the pipe to transfer heat or coolth inside directly. This kind of structure is named "active pipe-embedded building envelope" due to dealing with the thermal energy actively inside the structure mass by circulating water. This structure not only deals with thermal energy before the external disturbance becomes cooling/heating load by using the circulating water, but also may use low-grade energy sources such as evaporative cooling, solar energy, and geothermal energy. In the meantime, this structure can also improve the indoor thermal comfort by tempering the internal wall surface temperature variation due to the thermal removal in the mass. This work further presents the thermal performance of this structure under a typical hot summer weather condition by comparing it with that of the conventional external wall/roof with numerical simulation. The results show that this pipe-embedded structure may reduce the external heat transfer significantly and reduce the internal wall surface temperature for improving thermal comfort. This work also presents the effects of the water temperature and the pipe spacing on the heat transfer of this structure. The internal surface heat transfer may reduce by about 2.6 W/mE when the water temperature reduces by 1℃ as far as a brick wall with pipes embedded inside is concerned. When the pipe spacing reduces by 50 mm, the internal wall surface heat flux can also reduce by about 2.3 W/m2.展开更多
Combining two non-contact testing instruments of a three-dimensional body measure system and an infrared camera, the entrapped air gap under clothing and the clothing surface temperature distribution were measured wit...Combining two non-contact testing instruments of a three-dimensional body measure system and an infrared camera, the entrapped air gap under clothing and the clothing surface temperature distribution were measured without interfering the air gap state. It was discussed the effect of different air gap size on subjective clothing sensation. At the same time, taken the subjective sensations of moisture, adhesiveness and mugginess from the lower back as example, the relationship among the subjective evaluation, the air gap size and the clothing surface temperature were analyzed.展开更多
The safety and the fatigue comfort were compared between a domestic and a Japanese postal bicycle. Firstly, the fatigue comfort of these two kinds of bicycles was evaluated by surface electromyographic signal (sEMG) e...The safety and the fatigue comfort were compared between a domestic and a Japanese postal bicycle. Firstly, the fatigue comfort of these two kinds of bicycles was evaluated by surface electromyographic signal (sEMG) experiment, in which human lower limb muscle groups were research objects, and the average EMG (AEMG) index and median frequency (MF) were chosen as the evaluation indexes. Secondly, the safety of these two kinds of bicycle frames was analyzed and compared by using the finite element analysis. The results show that the riding fatigue comfort of the Japanese postal bicycle is better, and the Japanese postal bicycle frame is more safe and reasonable although both the postal bicycles meet the requirement for strength. Finally, based on the above analysis, the frame structure and related parameters of the domestic postal bicycle were improved with reference to the Japanese postal bicycle and biomechanics theory.展开更多
The study aims to investigate the thermal comfort requirements in residential buildings and to establish an adaptive thermal comfort model in the cold zone of China.A year-long field study was conducted in residential...The study aims to investigate the thermal comfort requirements in residential buildings and to establish an adaptive thermal comfort model in the cold zone of China.A year-long field study was conducted in residential buildings in Xi’an,China.A total of 2069 valid questionnaires,along with indoor environmental parameters were obtained.The results indicated occupants’thermal comfort requirements varied with seasons.The neutral temperatures were 17.9,26.1(highest),25.2,and 17.4℃(lowest),and preferred temperatures were 23.2,25.6(highest),24.8,and 22.4℃(lowest),respectively for spring,summer,autumn,and winter.The neutral temperature and preferred temperature in autumn are close to the neutral temperature in summer,while the neutral temperature and preferred temperature in spring are close to that in winter.Besides,the 80%and 90%acceptable temperature ranges,adaptive thermal comfort models,and thermal comfort zones for each season were established.Human’s adaptability is related to his/her thermal experience of the current season and the previous season.Therefore,compared with the traditional year-round adaptive thermal comfort model,seasonal models can better reflect seasonal variations of human adaptation.This study provides fundamental knowledge of the thermal comfort demand for people in this region.展开更多
文摘An investigation on relationship between clothing pressure of men's suit and wearing comfort is conducted. With the pressure measurements at different parts of men's suit under normal standing posture and in motion, the objective assessment of the total comfort are related to the subjective ratings of clothing pressure. There is a common strong sensation of pressure on shoulder with normal standing posture, and a strong relationship between total comfort and clothing pressure in back armhole and the front of upper arm with posture in motion.
文摘With the global promotion of LED lighting products, the health and safety of LED products has drawn wider attention. This paper systematically introduces the ergonomic evaluation (methods and indicators) svstem for heahh and comfort which differs from the traditional manpowered physical detection, and sketches out the evaluation indicators and its industrialization prospect.
文摘Skin seasitive difference of human body sections under clothing is the theoretic foundation of thermal insulation clothing design. By a new psychological & physical researching method, the subjective psychological perception of human body sections affected by the same cold stimulus are studied, and with Thurstone comparative judgement the main human body sections' cold sensitivity sequences are obtained. Furthermore the physiological causes for skin sensitive difference of human body sections under clothing are suggested.
基金The National Natural Science Foundation of China(No.5087125)
文摘The local skin temperatures of 22 subjects at air temperatures of 21,24,26,29 ℃ are measured,and the mean skin temperatures are calculated by ten skin temperature measuring points.The thermal comfort levels and the thermal sensations of these subjects are also investigated by a questionnaire.The Mahalanobis distance discrimination method is applied to establish the evaluation model for the thermal comfort based on the mean skin temperature.The experimental results indicate that the difference of the mean skin temperatures between the comfort level and the discomfort level is significant.Using the evaluation model,the mean skin temperature at the thermal comfort level is 32.6 to 33.7 ℃,and the thermal comfort levels of 72% of the subjects are correctly evaluated.The accuracy of the evaluation model can be improved when the effects of sex of the subject on the mean skin temperature and the thermal comfort are considered.It can be concluded that the mean skin temperature can be used as an effective physiological indicator to evaluate human thermal comfort in a steady thermal environment.
基金The National Natural Science Foundation of China(No.50838003)the National Key Technology R&D Program of China during the 11th Five-Year Plan Period(No.2006BAJ02A06)
文摘This paper introduces a field measurement of an indoor thermal environment in rural housing in suburban Beijing from December 2008 to March 2009.The indoor environment parameters such as air temperature,mean radiant temperature(MRT),airflow velocity and relative humidity are measured.A questionnaire survey of the occupants' thermal sensations in these surveyed houses is conducted and their daily activities and clothing conditions are recorded.The results show that the thermal neutral temperature of rural housing is 18.4 ℃,and the lower limit of acceptable temperature range can be extended to 10.9 ℃.The comfortable indoor temperature is affected by the occupants' clothing and lifestyle.Therefore,the indoor temperature standards of space heating for suburban housing cannot be simply duplicated from that for urban housing.Compared with occupants in suburban Beijing,it is found that the occupants in rural Hunan province feel colder at the same operative temperature due to the high relative humidity in Hunan province.
基金The National Natural Science Foundation of China(No.50878125)
文摘To improve the accuracy of skin temperature measurements in thermal comfort research,a new measurement method based on a new thermometer is proposed.A platinum film resistance(Pt1000)sensor of the thermometer is welded on a printed circuit board to eliminate the heat loss from the leads and avoid the influence of the surrounding thermal environment.In order to determine the suitable thickness of the board,a steady heat conduction model is established.The simulation results reveal that when the thickness of the board is 0.2 mm,the influence of the surrounding air can be effectively prevented and the skin temperature does not obviously increase.The experimental results of verification show that the maximum measurement error of the skin temperature measured by the thermometer is 0.24 ℃,and the average measurement error of the skin temperature is 0.04 ℃.The proposed method provides an effective and reliable option for the skin temperature measurement in thermal comfort research.
基金The National Natural Science Foundation of China(No.51508257,51668042,51578274)the Yangtze River Scholar and the Innovation Team of M inistry of Education(No.IRT13068)the Scientific Research Project of Gansu Higher Education(No.2015B-34)
文摘The human-induced vertical vibration serviceability of low-frequency and lightweight footbridges is studied based on the moving mass-spring-damper(MMSD) biodynamic model, and the mass damper(TMD) with different optimal model parameters being used to control the vertical vibration.First, the MMSD biodynamic model is employed to simulate the pedestrians, and the time-varying control equations of the vertical dynamic coupling system of the pedestrian-bridgeTMD are established with the consideration of pedestrianbridge dynamic interaction; and the equations are solved by using the Runge-Kutta-Felhberg integral method with variable step size. Secondly, the footbridge dynamic response is calculated under the model of pedestrian-structure dynamic interaction and the model of moving load when the pedestrian pace frequency is consistent with the natural frequency of footbridge. Finally, a comparative study and analysis are made on the control effects of the vertical dynamic coupling system in different optimal models of the TMD. The calculation results show that the pedestrian-bridge dynamic interaction cannot be ignored when the vertical human-induced vibration serviceability of low-frequency and light-weight footbridge is evaluated. The TMD can effectively reduce the vibration under the resonance of pedestrian-bridge, and TMD parameters are recommended for the determination by the Warburton optimization model.
基金The National Key Technology R&D Program of Chinaduring the 11th Five-Year Plan Period(No.2008BAJ12B05)
文摘Field measurements on thermal comfort were carried out in a building with double-skin faade from January 14th to 16th,2009.Data are obtained by measurements of physical parameters and a questionnaire survey is conducted at the same time in 27 offices of the building.The subjective survey involves questions on demographic information of the occupants,health status,environmental comfort conditions and acceptance.A total of 150 occupants are investigated and 131 questionnaires are completed.The statistical data presents the distributions of predicted mean vote,mean thermal sensation vote,mean thermal comfort vote,thermal acceptability,etc.The results show that low relative humidity is the main reason causing thermal discomfort.The greatest discomfort is dry mouth and eye dryness which are caused by low relative humidity.The females are verified to be more sensitive than the males.Meanwhile,a double-skin faade represents a good noise insulation effect while the glare problem is still unresolved.
基金The National Natural Science Foundation of China(No. 51036001 )the Natural Science Foundation of Jiangsu Province(No. BK2010043)
文摘A new ground source heat pump system combined with radiant heating/cooling is proposed, and the principles and the advantages of the system are analyzed. A demonstration of the system is applied to a rebuilt building: Xijindu exhibition hall, which is located in Zhenjiang city in China. Numerical studies on the thermal comfort and energy consumption of the system are carded out by using TRNSYS software. The results indicate that the system with the radiant floor method or the radiant ceiling method shows good thermal comfort without mechanical ventilation in winter. However, the system with either of the methods should add mechanical ventilation to ensure good comfort in summer. At the same level of thermal comfort, it can also be found that the annual energy consumption of the radiant ceiling system is less than that of the radiant floor system.
基金Supported by Program for New Century Excellent Talents in University (070003)the Natural Science Foundation of Anhui Province (070414154)~~
文摘A systematic and effective optimization is proposed for the design of a three-dimensional (3-D) vehicle suspension model with eight degrees of freedom (DOF), including vertical seat motion, vehicle suspension, pitching and rolling motions, and vertical wheel motions using the evolutionary game theory. A new design of the passive suspension is aided by game theory to attain the best compromise between ride quality and suspension deflections. Extensive simulations are performed on three type road surface models A, B, C pavement grades based on the guidelines provided by ISO-2631 with the Matlab/Simulink environment. The preliminary results show that, when the passive suspension is optimized via the proposed approach, a substantial improvement in the vertical ride quality is obtained while keeping the suspension deflections within their allowable clearance when the vehicle moves at a constant velocity v=20 m/s, and the comfort performance of a suspension seat can be enhanced by 20%-30%.
基金The National Natural Science Foundation of China(No.50478113)the Leading Academic Discipline Project of Shanghai Municipal Education Commission(No.J50502)
文摘To study the draft sensation distribution of an air jet supply system in a large space building in summer,experiments are conducted in a large laboratory.The temperature,velocity and draft sensation distributions at a nozzle height of 4 m in the occupied zone are obtained.Then,the numerical simulation under the test condition is carried out by the computational fluid dynamics(CFD)method.The calculation results of the indoor vertical temperature and the draft sensation distribution are validated by the test data.Simulations with different nozzle heights are conducted.The satisfactory air supply condition is determined by analyzing the draft sensations and the temperatures in the occupied zone under three conditions.The simulation results show that the optimal draft sensation distribution and the uniform temperature and velocity fields can be obtained at a nozzle height of 5 m.
基金Supported by"10-people Program"of Gansu Meteorological BureauSocial Welfare Study Program of Special Industry (GYHY200806021)Launched by the Ministry of Science and Technology~~
文摘Based on the meteorological data of 12 weather stations in the east section of silk road from 1971 to 2005, such as average monthly temperature, relative humidity, wind speed and sunshine duration, its climatic tourism comfort was analyzed by adopting temperature-humidity index, wind-chill index and index of cloth. The results showed that the most comfortable month for travelling in this region is May and September. From east to west, the climatic comfort of such a section is decreasing. The most suitable tourism season is summer, followed by autumn and spring, the least suitable season is winter.
文摘While many harmful algal blooms have been associated with increasing eutrophication, not all species respond similarly and the increasing challenge, especially for resource managers, is to determine which blooms are related to eutrophication and to understand why particular species proliferate under specific nutrient conditions. The overall goal of this brief review is to describe why nutrient loads are not changing in stoichiometric proportion to the "Redfield ratio", and why this has important consequences for algal growth. Many types of harmful algae appear to be able to thrive, and/or increase their production of toxins, when nutrient loads are not in proportion classically identified as Redfield ratios. Here we also describe some of the physiological mechanisms of different species to take up nutrients and to thrive under conditions of nutrient imbalance.
文摘Vehicle suspension design includes a number of compromises to provide good leveling of stability and ride comfort. Optimization of off-road vehicle suspension system is one of the most effective methods, which could considerably enhance the vehicle stability and controllability. In this work, a comprehensive optimization of an off-read vehicle suspension system model was carried out using software ADAMS. The geometric parameters of suspension system were optimized using genetic algorithm (GA) in a way that ride comfort, handling and stability of vehicle were improved. The results of optimized suspension system and variations of geometric parameters due to road roughness and different steering angles were presented in ADAMS and the results of optimized and conventional suspension systems during various driving maneuvers were compared. The simulation results indicate that the camber angle variations decrease by the optimized suspension system, resulting in improved handling and ride comfort characteristics.
基金Supported by The Biological Medical Engineering Foundation of First Affiliated Hospital of Xinjiang Medical University
文摘AIM:To demonstrate the value of Diosmin(flavonidic fraction)in the management of post-haemorhoidectomic symptoms.METHODS:Eighty-six consecutive patients with grades ⅢandⅣacute mixed hemorrhoids admitted to the Anorectal Surgical Department of First Affiliated Hospital,Xinjiang Medical University from April 2009 to April 2010,were enrolled in this study.An observerblinded,randomized trial was conducted to compare post-haemorhoidectomic symptoms with use of Diosmin flavonidic fraction vs placebo.Eighty-six patients were randomly allocated to receive Diosmin flavonidic fraction 500 mg for 1 wk(n=43)or placebo(n=43).The Milligan-Morgan open haemorrhoidectomy was performed by a standardized diathermy excision method.Pain,bleeding,heaviness,pruritus,wound edema and mucosal discharge were observed after surgery.The postoperative symptoms and hospitalization time were recorded.RESULTS:The mean age of the Diosmin group and controls was 53.2 and 51.3 years,respectively.In Diosmin group,haemorrhoid piles were of the third degree in 33 patients and the fourth degree in 10;and in the control group,29 were of the third degree and 14 were of the fourth degree.There was no statistically significance in age,gender distribution,degree and number of excised haemorrhoid piles,and the mean duration of haemorrhoidal disease between the two groups.There was a statistically significant improvement in pain,heaviness,bleeding,pruritus from baseline to the 8th week after operation(P<0.05).Patients taking Diosmin had a shorter hospitalization stay after surgery(P< 0.05).There was also a significant improvement on the proctoscopic appearance(P<0.001).However,there was no statistical difference between the two groups in terms of wound mucosal discharge.Two patients experienced minor bleeding at the 8th week in Diosmin group,and underwent surgery.CONCLUSION:Diosmin is effective in alleviating postoperational symptoms of haemorrhoids.Therefore,it should be considered for the initial treatment after haemorrhoid surgery.However,further prospective randomized trials are needed to confirm the findings of this study.
基金Project(51178201) supported by the National Natural Science Foundation of China Project(2011CDB292) supported by the Natural Science Foundation of Hubei Province,China
文摘An active pipe-embedded building envelope, which is an external wall or roof with pipes embedded inside, was presented. This structure may utilize the circulating water in the pipe to transfer heat or coolth inside directly. This kind of structure is named "active pipe-embedded building envelope" due to dealing with the thermal energy actively inside the structure mass by circulating water. This structure not only deals with thermal energy before the external disturbance becomes cooling/heating load by using the circulating water, but also may use low-grade energy sources such as evaporative cooling, solar energy, and geothermal energy. In the meantime, this structure can also improve the indoor thermal comfort by tempering the internal wall surface temperature variation due to the thermal removal in the mass. This work further presents the thermal performance of this structure under a typical hot summer weather condition by comparing it with that of the conventional external wall/roof with numerical simulation. The results show that this pipe-embedded structure may reduce the external heat transfer significantly and reduce the internal wall surface temperature for improving thermal comfort. This work also presents the effects of the water temperature and the pipe spacing on the heat transfer of this structure. The internal surface heat transfer may reduce by about 2.6 W/mE when the water temperature reduces by 1℃ as far as a brick wall with pipes embedded inside is concerned. When the pipe spacing reduces by 50 mm, the internal wall surface heat flux can also reduce by about 2.3 W/m2.
基金Supported by Shanghai Science and Technology Ministry Phosphor Project (No.05QMX1402)
文摘Combining two non-contact testing instruments of a three-dimensional body measure system and an infrared camera, the entrapped air gap under clothing and the clothing surface temperature distribution were measured without interfering the air gap state. It was discussed the effect of different air gap size on subjective clothing sensation. At the same time, taken the subjective sensations of moisture, adhesiveness and mugginess from the lower back as example, the relationship among the subjective evaluation, the air gap size and the clothing surface temperature were analyzed.
基金Supported by Special Fund Project for Technology Innovation of Tianjin (No.10FDZDGX00500)Tianjin Product Quality Inspection Technology Research Institute
文摘The safety and the fatigue comfort were compared between a domestic and a Japanese postal bicycle. Firstly, the fatigue comfort of these two kinds of bicycles was evaluated by surface electromyographic signal (sEMG) experiment, in which human lower limb muscle groups were research objects, and the average EMG (AEMG) index and median frequency (MF) were chosen as the evaluation indexes. Secondly, the safety of these two kinds of bicycle frames was analyzed and compared by using the finite element analysis. The results show that the riding fatigue comfort of the Japanese postal bicycle is better, and the Japanese postal bicycle frame is more safe and reasonable although both the postal bicycles meet the requirement for strength. Finally, based on the above analysis, the frame structure and related parameters of the domestic postal bicycle were improved with reference to the Japanese postal bicycle and biomechanics theory.
基金Project(51325803)supported by the National Science Foundation for Distinguished Young Scholars of ChinaProject(2020M673489)supported by China Postdoctoral Science FoundationProject(2020-K-196)supported by the Science and Technology Project of Ministry of Housing and Urban-Rural Development,China。
文摘The study aims to investigate the thermal comfort requirements in residential buildings and to establish an adaptive thermal comfort model in the cold zone of China.A year-long field study was conducted in residential buildings in Xi’an,China.A total of 2069 valid questionnaires,along with indoor environmental parameters were obtained.The results indicated occupants’thermal comfort requirements varied with seasons.The neutral temperatures were 17.9,26.1(highest),25.2,and 17.4℃(lowest),and preferred temperatures were 23.2,25.6(highest),24.8,and 22.4℃(lowest),respectively for spring,summer,autumn,and winter.The neutral temperature and preferred temperature in autumn are close to the neutral temperature in summer,while the neutral temperature and preferred temperature in spring are close to that in winter.Besides,the 80%and 90%acceptable temperature ranges,adaptive thermal comfort models,and thermal comfort zones for each season were established.Human’s adaptability is related to his/her thermal experience of the current season and the previous season.Therefore,compared with the traditional year-round adaptive thermal comfort model,seasonal models can better reflect seasonal variations of human adaptation.This study provides fundamental knowledge of the thermal comfort demand for people in this region.