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Wind⁃resistant fuzzy comfortability assessment for a super⁃high tower crane based on the PDEM 被引量:2
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作者 LIU Yun WANG Hao +2 位作者 LI Bing XU Zidong MAO Jianxiao 《Journal of Southeast University(English Edition)》 2025年第1期51-57,共7页
The fuzzy comfortability of a wind-sensitive super-high tower crane is critical to guarantee occupant health and improve construction efficiency.Therefore,the wind-resistant fuzzy comfortability of a super-high tower ... The fuzzy comfortability of a wind-sensitive super-high tower crane is critical to guarantee occupant health and improve construction efficiency.Therefore,the wind-resistant fuzzy comfortability of a super-high tower crane in the Ma’anshan Yangtze River(MYR)Bridge site is analyzed in this paper.First,the membership function model that represents fuzzy comfortability is introduced in the probability density evolution method(PDEM).Second,based on Fechner’s law,the membership function curves are constructed according to three acceleration thresholds in ISO 2631.Then,the fuzzy comfortability for the super-high tower crane under stochastic wind loads is assessed on the basis of different cut-set levelsλ.Results show that the comfortability is over 0.9 under the required maximum operating wind velocity.The low sensitivity toλcan be observed in the reliability curves of ISOⅡandⅢmembership functions.The reliability of the ISOⅠmembership function is not sensitive toλwhenλ<0.7,whereas it becomes sensitive toλwhenλ>0.7. 展开更多
关键词 comfort reliability probability density evolution method fuzzy theory membership function tower crane long-span bridge
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Impact of Duty Cycling HVAC Systems on Thermal Comfort,Energy Consumption,and Operational Costs
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作者 Alya Penta Agharid Indra Permana +2 位作者 Linlan Chang Yi-Han Luo Fujen Wang 《Energy Engineering》 2025年第9期3839-3866,共28页
Air conditioning(AC)is essential for maintaining indoor comfort during Taiwan region’s hot and humid summers but significantly contributes to increased energy consumption.This study evaluates the effects of AC dutycy... Air conditioning(AC)is essential for maintaining indoor comfort during Taiwan region’s hot and humid summers but significantly contributes to increased energy consumption.This study evaluates the effects of AC dutycycling strategies on energy performance,thermal comfort,and operational costs in office environments.Duty-cycling was implemented using a building energy management system(BEMS),which remotely controlled the ON/OFF cycles of AC units.Five duty-cycling modes were tested,with some modes incorporating air circulation during OFF periods.Field measurements of energy consumption,temperature,humidity,and air velocity were conducted and integrated with thermal comfort analysis tools to calculate predictedmean vote(PMV)and percentage of dissatisfied(PPD)values.The objective was to achieve energy savings while maintaining acceptable thermal comfort levels.Results show that Mode A achieved the highest energy savings,reducing monthly consumption by 40.79%;however,it slightly exceeded the PMV threshold(+0.5)and recorded a PPD greater than 10%,indicating reduced occupant comfort.In contrast,Mode C provided a better balance,achieving a 27.61%reduction in energy consumption while maintaining a PMV of+0.28 and a PPD of 7.49%,both within acceptable comfort limits.Despite the energy-saving benefits,not all dutycycling modes ensured satisfactory thermal comfort.Additionally,the cost analysis revealed thatMode A achieved the lowest monthly electricity cost(NTD 8476.18/USD 263.38),whileMode C incurred a higher cost(NTD 10,363.00/USD 322.01),highlighting the trade-off between energy savings,comfort,and economic impact. 展开更多
关键词 Air conditioning duty cycle ENERGY-SAVING thermal comfort field measurement
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Effect of comprehensive perioperative nursing on pain intensity,complication rates,and comfort levels in patients undergoing gallstone surgery
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作者 Chen-Yan Bao Xiao-Kun Ding +2 位作者 Qiao-Fei Qi Peng Ye Ze-Jun Fang 《World Journal of Gastrointestinal Surgery》 2025年第2期111-119,共9页
BACKGROUND Surgery is the gold standard for gallstone treatment.Nevertheless,the complications associated with the surgical procedure can exert diverse and adverse impacts on patients’health and quality of life to va... BACKGROUND Surgery is the gold standard for gallstone treatment.Nevertheless,the complications associated with the surgical procedure can exert diverse and adverse impacts on patients’health and quality of life to varying extents.Hence,it is essential to offer perioperative care to patients undergoing gallstone surgery.AIM To examine the impact of perioperative comprehensive nursing on pain intensity,complication rates,and patient comfort in individuals undergoing gallstone surgery.METHODS From February 2022 to February 2024,195 patients who underwent gallstone surgery at Sanmen People’s Hospital were selected and divided into two groups:A control group receiving routine nursing care(95 patients)and a research group receiving perioperative comprehensive nursing(100 patients).Key postoperative recovery indicators,including time to first postoperative anal exhaust,oral food intake,and ambulation,were observed,along with pain intensity(measured by the numeric rating scale),complication rate(bleeding,incision infection,recurrence),patient comfort(assessed using the visual analogue scale),and quality of life(measured by the World Health Organization Quality of Life-BREF).RESULTS The research group showed significantly shorter times to first postoperative anal exhaust,oral intake,and ambulation.Moreover,numeric rating scale pain scores in the research group were markedly lower post-nursing,and the total complication rate was significantly reduced compared to the control group.Furthermore,comfort levels improved considerably in the research group,and World Health Organization Quality of Life-BREF scores across the physical,psychological,social,and environmental domains were significantly higher compared to the control group following nursing care.CONCLUSION Perioperative comprehensive nursing effectively enhances postoperative recovery in patients undergoing gallstone surgery,reducing pain,lowering complications,and improving patient comfort and quality of life,which deserves clinical application. 展开更多
关键词 Perioperative comprehensive nursing Gallstone surgery Pain intensity Complication rate comfort
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Passenger Comfort Assessment via Motion Complexity Analysis for Autonomous Vehicles
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作者 Titong Jiang Jingyuan Li +2 位作者 Liang Ma Xuewu Ji Yahui Liu 《Chinese Journal of Mechanical Engineering》 2025年第5期258-274,共17页
Traditionally,passenger comfort in vehicles is perceived as being most influenced by acceleration and jerk.Consequently,the current research primarily focuses on developing control algorithms to limit the maximum acce... Traditionally,passenger comfort in vehicles is perceived as being most influenced by acceleration and jerk.Consequently,the current research primarily focuses on developing control algorithms to limit the maximum acceleration and jerk of the vehicle in order to improve passenger comfort.However,naturalistic driving studies demonstrate that such simple characteristics are insufficient for accurately evaluating passenger comfort.This study identifies motion complexity as a key factor of passenger comfort.A series of naturalistic driving studies are conducted,during which passenger comfort is assessed using a 5-point Likert scale.Moreover,a real-time passenger comfort measurement based on electromyography(EMG)and stepwise regression is proposed to facilitate seamless data collection.Time-series features representing motion complexity are then introduced to better describe passenger comfort.Hierarchical regression confirms that simple characteristics of motion are insufficient to explain passenger comfort,and shows that the proposed motion complexity features have a substantial effect on passenger comfort.Finally,a machine learning-based real-time passenger comfort estimation method is developed according to the foregoing findings.Experimental results show that the proposed method can accurately estimate passenger comfort in real-time using only vehicle motion information.The findings of this study suggest that vehicle motion complexity should be considered in future passenger comfort studies. 展开更多
关键词 Autonomous driving Passenger comfort Motion complexity Regression analysis Machine learning
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Brutal Truth or a Comforting Lie?
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《ChinAfrica》 2025年第2期60-61,共2页
The Double Take column looks at a single topic from an African and Chinese perspective.This month,we delve into the dilemma of choosing between telling the harsh truth and offering a wellintentioned lie.
关键词 offering comfort COLUMN
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Impact of Window-to-Wall Ratio on Thermal Comfort and Energy Performance of Hybrid Cooling Systems
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作者 Dong Liu Runze Zhang +4 位作者 Anjie Hu Na Liu Liu Tang Xiaozhou Wu Jun Wang 《Fluid Dynamics & Materials Processing》 2025年第10期2579-2612,共34页
This study compares two end-cooling systems,convective-radiant combined cooling(FR+FC)and fan coil convection(FC),through continuous experimental investigations,focusing on the impact of window-to-wall ratio(WWR)on in... This study compares two end-cooling systems,convective-radiant combined cooling(FR+FC)and fan coil convection(FC),through continuous experimental investigations,focusing on the impact of window-to-wall ratio(WWR)on indoor thermal comfort,temperature distribution,humidity,and energy consumption.Results show that increasing WWR amplifies indoor temperature fluctuations.While the overall predicted mean vote(PMV)remains within the Level-II comfort range(−1.0 to+1.0),the FC system exhibits pronounced local PMV gradients near west-facing windows,especially at 80%WWR,where transient PMV reaches 1.26 close to the window,0.89 higher than at the room center.In contrast,the FR+FC system significantly reduces spatial PMV variations,maintaining local PMV within acceptable limits for most of the day.Energy analysis reveals that FC energy consumption rises with WWR,increasing by 7.11%from 40%to 80%WWR,whereas FR+FC energy use decreases by 29.26%over the same range,demonstrating its superior handling of radiant loads.Furthermore,the convective-radiant system exhibits a high average hourly cooling performance coefficient.These findings indicate that FR+FC systems provide better thermal comfort and energy efficiency in high-WWR spaces,making them particularly suitable for summer operation in window-intensive buildings. 展开更多
关键词 Window-to-wall ratio solar radiation thermal comfort energy consumption
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Enhancing Transcranial Magnetic Stimulation Comfort:The Role of Electrical Stimulation in Pain Reduction
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作者 Zihui Qi Zhengyi Yang +3 位作者 Hao Liu Lingzhong Fan Nianming Zuo Tianzi Jiang 《Neuroscience Bulletin》 2025年第1期155-158,共4页
Dear Editor,Transcranial Magnetic Stimulation(TMS)has emerged as a promising therapeutic tool for various neurological and psychiatric conditions[1-3].However,despite its potential benefits,TMS is not without its disc... Dear Editor,Transcranial Magnetic Stimulation(TMS)has emerged as a promising therapeutic tool for various neurological and psychiatric conditions[1-3].However,despite its potential benefits,TMS is not without its discomfort issues[4,5],which are mainly related to target location,stimulus intensity,and treatment duration.The discomfort associated with TMS arises from several factors,including the physical sensations experienced during the procedure and potential adverse effects on the scalp and surrounding tissues. 展开更多
关键词 comfort SENSATION STIMULATION
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Energy-Efficient Air Conditioning System with Combined a Ceiling Fan for Thermal Comfort in an Office
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作者 Linlan Chang Win-Jet Luo +3 位作者 Indra Permana Bowo Yuli Prasetyo Alya Penta Agharid Fujen Wang 《Energy Engineering》 2025年第5期1771-1787,共17页
Heating,Ventilation,andAir Conditioning(HVAC)systems are critical formaintaining thermal comfort in office environments which also crucial for occupant well-being and productivity.This study investigates the impact of... Heating,Ventilation,andAir Conditioning(HVAC)systems are critical formaintaining thermal comfort in office environments which also crucial for occupant well-being and productivity.This study investigates the impact of integrating ceiling fans with higher air conditioning setpoints on thermal comfort and energy efficiency in office environments.Field measurements and questionnaire surveys were conducted to evaluate thermal comfort and energysaving potential under varying conditions.Results show that increasing the AC setpoint from 25○C to 27○C,combined with ceiling fan operation,reduced power consumption by 10%,achieving significant energy savings.Survey data confirmed that 85%of participants reported consistent thermal sensations across all conditions,with ceiling fans effectively compensating for higher setpoints through enhanced air circulation.CFDsimulations revealed that mediumspeed ceiling fan operation produced the most uniformairflowdistribution,with an average air velocity of 0.45 m/s,and minimized temperature variations,ensuring balanced thermal conditions.Temperature analysis showed a reduction in hotspots and cold zones,maintaining an average temperature deviation of less than±0.5○C.Predicted Mean Vote(PMV)evaluations at a 27○C setpoint indicated improved thermal comfort,with average PMV values around−0.3,corresponding to a“neutral”thermal sensation.These findings demonstrate the effectiveness of integrating ceiling fans with HVAC systems in achieving energy efficiency and occupant comfort,offering a sustainable approach to reducing AC energy consumption in office environments. 展开更多
关键词 Thermal comfort ceiling fan field measurement questionnaire survey numerical simulation
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Design Optimization with Building Forms and Their Effects on Outdoor Thermal Comfort:The Case of Composite Climate of Lucknow,India
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作者 Swetika Porwal Shailendra K.Mandal Subhrajit Banerjee 《Journal of Environmental & Earth Sciences》 2025年第4期339-350,共12页
The recent development in Lucknow shows that the amount of built mass may increase significantly soon,which may affect outdoor thermal comfort.This study aims to achieve a better alternative to the geometrical configu... The recent development in Lucknow shows that the amount of built mass may increase significantly soon,which may affect outdoor thermal comfort.This study aims to achieve a better alternative to the geometrical configuration of vertical surfaces that helps improve the outdoor thermal comfort level.The study primarily deals with the exploration of built forms by altering the planar forms,heights,and orientations to arrive at a better composition of vertical surfaces.144 typologies were finally generated,which were then simulated in ENVI-met.The results show that,with the I-shaped typology it is difficult to reduce solar access,whereas in terms of ventilation,the typology performed better than L-shaped and C-shaped typologies.For this reason,the hours of solar access,as well as wind speed,should be seen together while developing the built-form typology.Urban neighborhoods can be designed with streets and open spaces oriented primarily to northeast-southwest and northwest-southeast directions which allow the open spaces to be thermally more comfortable than the rest of the orientation.This research highlights the importance of varying building heights to enhance thermal comfort.The findings provide valuable insights for composite climate cities like lucknow and can serve as a framework for future design strategies aimed at mitigating outdoor thermal discomfort.It is therefore important for planners,urban designers,and architects to design considering the minimal impact of the upcoming development on the thermal comfort level. 展开更多
关键词 Outdoor Thermal comfort Composite Climate Design Optimization Physiological Equivalent Temperature Vertical Surfaces
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Comfort nursing intervention prevents incontinence-associated dermatitis in critically ill patients
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作者 Linlin Zou Siting Jiang +1 位作者 Ron Jiang Lin Cai 《Precision Nursing》 2025年第1期11-17,共7页
Objective:To evaluate the clinical effect of comfort nursing intervention in preventing incontinent-associated dermatitis(IAD)and related complications in critically ill patients.Methods:This study enrolled critically... Objective:To evaluate the clinical effect of comfort nursing intervention in preventing incontinent-associated dermatitis(IAD)and related complications in critically ill patients.Methods:This study enrolled critically ill patients from the Intensive Care Unit at Ningxiang People’s Hospital between June 2020 and June 2024.Patients were randomly assigned to a comfort nursing group(n=51)and a routine nursing group(n=53).The comfort nursing group received comprehensive comfort nursing,while the routine nursing group received standard care.The incidence,classification and area of IAD as well as the incidence of complications and patient/family satisfaction with nursing care,were assessed.Results:The incidence of IAD was significantly lower in the comfort nursing group(8 patients)compared to the routine nursing group(21 patients)(P<0.05).Additionally,the incidences of wound infection and muscle soreness were notably lower in the comfort nursing group(both P<0.05).Patient and family satisfaction in the comfort nursing group was significantly higher than in the routine nursing group(both P<0.05).Conclusion:Comfort nursing intervention is effective in preventing IAD and reducing associated complications in critically ill patients,thereby improving patient and family satisfaction with treatment. 展开更多
关键词 comfort nursing incontinence-associated dermatitis critically ill patients SATISFACTION
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Designing Temporary Installations beneath Toronto’s Gardiner Expressway to Enhance Thermal Comfort during Shoulder Seasons
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作者 Niloufar Mohsenivafa Afshin Ashari Nadia Amoroso 《Journal of Environmental Science and Engineering(B)》 2025年第3期103-122,共20页
Urban underutilized spaces,often the secondary by-products of large infrastructure projects,are often overlooked,despite their potential to enhance city life.With meaningful design interventions,these neglected areas ... Urban underutilized spaces,often the secondary by-products of large infrastructure projects,are often overlooked,despite their potential to enhance city life.With meaningful design interventions,these neglected areas can be transformed into inclusive public environments that offer social,environmental,and cultural value.This research investigates how modular,temporary installations beneath Toronto’s Gardiner Expressway,in Canada,can enhance thermal comfort and foster community engagement during the shoulder seasons.Using a multi-step methodology,including literature review,thermal comfort guidelines,site-specific climate analysis,and precedent studies,the research identifies key design strategies tailored to the unique microclimatic and social conditions of under-bridge spaces.The study culminates in the proposal of a flexible system of movable panels that provide wind protection,solar control,and opportunities for gathering,interaction,and rest.By reimagining these unnoticed infrastructure zones as adaptable,climate-responsive public spaces,this research contributes to sustainable urban design and highlights the importance of design strategies that address the challenges of a warming and increasingly variable climate. 展开更多
关键词 Thermal comfort under bridge public space temporary installation climate adaptation modular design MICROCLIMATE seasonal design.
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Review of Works on Comparison of Old Indigenous Residences with Modern Houses in India on Non-Subjective Indices of Thermal Comfort
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作者 Sanmarga Mitra Shailendra Kr.Mandal 《Journal of Environmental & Earth Sciences》 2025年第3期329-340,共12页
During the past few decades,we have witnessed the phenomenon of constant warming occurring everywhere on the globe.Cities have suffered from urban warming to a greater extent than any other part of the world,and Kolka... During the past few decades,we have witnessed the phenomenon of constant warming occurring everywhere on the globe.Cities have suffered from urban warming to a greater extent than any other part of the world,and Kolkata has one of the highest levels of urban warming of any city around the world.In Kolkata,73%of the buildings are residential,and it is this type of building that contributes to a significant amount of this warming.With the city of Kolkata as the case study,this paper aims at understanding the multiple domains of urban heat islands and thermal comfort within the context of the city,from a macro perspective of an urban heat island down to a micro perspective of a building level,with the ultimate aim of mitigating global warming through this study.Various research works have been undertaken in India and abroad to understand the individual as well as composite effect of various building components on the indoor thermal comfort.Researches have also been undertaken to compare and comprehend the differential thermal comfort of old indigenous residences with that of the new residential buildings.Hence,this paper discusses methods that have been applied in past works to evaluate the thermal comfort of old and new residential buildings in a non-subjective manner,without having recourse to user feedback,in the final segment that views the process of learning from comparing old and new residential buildings. 展开更多
关键词 Review of Works Global Warming Urban Heat Island Thermal comfort
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Multi-model Switching Control Study of a Full-Car Suspension System for Balancing Ride Comfort and Handling Stability
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作者 Fubao Xu Xiangjun Xia +3 位作者 Jing Cao Pengfei Liu Donghong Ning Haiping Du 《Chinese Journal of Mechanical Engineering》 2025年第5期83-100,共18页
The cooperative control of ride comfort and handling stability in automobile suspension systems presents a significant challenge in intelligent chassis system design.This complexity arises from the high degrees of fre... The cooperative control of ride comfort and handling stability in automobile suspension systems presents a significant challenge in intelligent chassis system design.This complexity arises from the high degrees of freedom,diverse operating conditions,and inherent trade-offs between performance metrics in full-car suspension systems.In this paper,a novel switching control strategy is proposed to better balance ride comfort and handling stability for a full-car suspension system.The system integrates a ride comfort controller and an anti-rollover controller,guided by a new rollover risk assessment indicator that requires fewer state variables.First,a vehicle suspension simplification model approach is introduced,reducing the fourteen-degree-of-freedom full-car suspension model to three two-degree-of-freedom models:vertical,pitch and roll.Based on these simplified models,vertical,roll,and pitch controllers are designed,simplifying the controller design process for full-car suspension systems.The ride comfort controller is constructed using the modal energy method in conjunction with the simplified model controllers,while the roll controller functions as the anti-rollover controller.The proposed rollover risk assessment indicator serves as the switching criterion between handling stability and ride comfort control.Experimental results demonstrate that the proposed switching control strategy effectively adapts to various road conditions,enabling the semi-active variable damping suspension system to perform multi-modal switching.Compared to a well-tuned passive suspension,vertical,roll,and pitch accelerations are reduced by 14.13%,13.02%and 13.08%,respectively,significantly improving ride comfort.Additionally,the system effectively mitigates rollover risk,achieving reductions in roll angle,roll speed,and roll acceleration by 19.69%,16.40%,and 29.96%,respectively,thereby greatly enhancing vehicle safety.Overall,the proposed switching control strategy achieves a successful balance between ride comfort and handling stability,enhancing overall driving performance. 展开更多
关键词 Full-car suspension Ride comfort Handling stability Modal energy method Rollover risk indicators
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Analysis of Daily Life,Spiritual Comfort,and Fall Safety Care Needs of Elderly People in Urban and Rural Areas
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作者 Fang Zheng Xiaojing Tang Xinyue Zhang 《Journal of Clinical and Nursing Research》 2025年第1期157-163,共7页
Objective: To examine the daily life care, spiritual comfort, and fall safety care needs of the elderly in urban and rural areas of Tangshan, along with their influencing factors. Methods: From August 2022 to April 20... Objective: To examine the daily life care, spiritual comfort, and fall safety care needs of the elderly in urban and rural areas of Tangshan, along with their influencing factors. Methods: From August 2022 to April 2023, an investigation was conducted among urban and rural elderly individuals aged over 75 years in Tangshan City using the Activities of Daily Living Scale, the Revised Community Elderly Fall Risk Assessment Tool, and the Loneliness Scale. Results: The study included 750 urban and 740 rural elderly individuals aged over 75 years. Matrix analysis revealed a significant proportion of fall safety care needs across various daily life and spiritual care requirements. Multiple factor analysis indicated that advanced age, lower education levels, a greater number of chronic diseases, and lower levels of family and social support were associated with higher care demands among the elderly in both urban and rural areas. These differences were statistically significant (P < 0.05). Conclusion: The elderly in urban and rural areas demonstrate a high demand for fall safety care. Particular attention should be given to individuals with lower education levels, those who are widowed, those with multiple chronic diseases, and those with low levels of family and social support to better meet the diverse care needs of this population. 展开更多
关键词 Elderly people Daily life care needs Spiritual comfort needs Fall safety care needs Matrix analysis
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Dynamic Modeling of the Three-Dimensional Seated Human Body for High-Speed Train Ride Comfort Analysis
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作者 Hanwen Xu Xinbiao Xiao +4 位作者 Xiaoqing Dong Jian Han Peng Chen Qin Hu Xuesong Jin 《Chinese Journal of Mechanical Engineering》 2025年第5期478-507,共30页
Typically,seat or floor acceleration is used to evaluate the ride comfort of a high-speed train.However,the dynamic performance of the human body significantly differs from that of the floor.Therefore,using the car bo... Typically,seat or floor acceleration is used to evaluate the ride comfort of a high-speed train.However,the dynamic performance of the human body significantly differs from that of the floor.Therefore,using the car body floor and seat accelerations to calculate the ride comfort index of a high-speed train may not reflect the true feelings of passengers.In this study,a 3D human-seat-vehicle-track coupling model was established to investigate the ride comfort of highspeed train passengers.The seated human model,which considers the longitudinal,lateral,vertical,pitching,yawing,and rolling motions,comprises the head,upper torso,lower torso,pelvis,thighs,and shanks.The model parameters were determined using multi-axis excitation measurement data based on a genetic algorithm.Subsequently,the applicability of the small-angle assumption and natural modes of the human model is analyzed.Using the coupling system model,the vibration characteristics of the human-seat interaction surface were analyzed.The ride comfort of the high-speed train and human body dynamic performance were analyzed under normal conditions,track geometric irregularities and train meeting conditions.The results showed that the passenger seats in the front and rear rows adjacent to the window had a higher acceleration value than the others.The human backrest and seat pad connection points have higher vibration amplitudes than the car body floor in the human-sensitive frequency range,indicating that using the acceleration values on the floor may underestimate the discomfort of passengers.The ride comfort of high-speed trains diminishes in the presence of track geometric irregularities and when trains pass each other.When the excitation frequency of track geometry irregularities approached the natural frequency of the human-seat-vehicle system,ride comfort in high-speed trains decreased significantly.Moreover,using seat acceleration to evaluate passenger ride comfort overlooks the vibration characteristics of the human body.The transient aerodynamic force generated when the train meets can cause a larger car body roll and lateral motion at 2 Hz,which,in turn,decreases the passenger ride comfort.This study presents a detailed human-seat-vehicle-track coupling system that can reflect a passenger’s dynamic performance under complex operating conditions. 展开更多
关键词 Seated human body High-speed train Ride comfort 3D Human body-seat-vehicle-track coupling coupled model
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Changing Characteristics of Comfort Index of Human Body in Bengbu City in the Past 40 Years under the Background of Climate Change
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作者 Lei SHAN Xian ZHANG +2 位作者 Lei TIAN Ranran HE Jingyang CHEN 《Meteorological and Environmental Research》 2024年第2期40-43,共4页
Based on the daily meteorological data of Bengbu City during 1981-2020,the changing characteristics of three elements needed for the calculation of the comfort index of human body(CIHB)were discussed,and daily CIHB wa... Based on the daily meteorological data of Bengbu City during 1981-2020,the changing characteristics of three elements needed for the calculation of the comfort index of human body(CIHB)were discussed,and daily CIHB was classified and discussed.The results show that from 1981 to 2020,annual average temperature tended to increase significantly.Annual average wind speed and relative humidity showed a decreasing trend before 2011 but an increasing trend after 2011.The duration of the four seasons in Bengbu City mainly rose in spring,reduced in winter,declined first and then increased in summer,and rose first and then decreased in autumn.As CIHB was at grades 1 and 9(the most uncomfortable),the three factors had different effects on them.For cold weather,the influence of relative humidity and wind speed on CIHB can not be ignored besides temperature.In hot weather,the influence of temperature was dominant,and the change of annual average temperature could well correspond to the change in the number of very hot days.In the context of climate warming,the number of cold days tended to decline generally,but it was larger in the years with fewer very cold days.Under the background of climate warming,there was no obvious change in the number of days of the overall comfort of human body.The number of hot days was closely related to the duration of summer,and the number of days of grade 8 rose significantly in the years with an increase in the duration of summer. 展开更多
关键词 Climate change Human comfort comfort index of human body(CIHB)
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A utility and easily fabricated dual-mode fiber film for efficient and comfortable thermal management
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作者 Jiyuan Yu Jian Zheng +3 位作者 Wei Wang Zhijia Zhu Chunyan Hu Baojiang Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期394-405,共12页
Nowadays, the global climate is constantly being destroyed and the fluctuations in ambient temperature are becoming more frequent. However, conventional single-mode thermal management strategies(heating or cooling) fa... Nowadays, the global climate is constantly being destroyed and the fluctuations in ambient temperature are becoming more frequent. However, conventional single-mode thermal management strategies(heating or cooling) failed to resolve such dynamic temperature changes. Moreover, developing thermal management devices capable of accommodating these temperature variations while remaining simple to fabricate and durable has remained a formidable obstacle. To address these bottlenecks, we design and successfully fabricate a novel dual-mode hierarchical(DMH) composite film featuring a micronanofiber network structure, achieved through a straightforward two-step continuous electrospinning process. In cooling mode, it presents a high solar reflectivity of up to 97.7% and an excellent atmospheric transparent window(ATW) infrared emissivity of up to 98.9%. Noted that this DMH film could realize a cooling of 8.1 ℃ compared to the ambient temperature outdoors. In heating mode, it also exhibits a high solar absorptivity of 94.7% and heats up to 11.9 ℃ higher than black cotton fabric when utilized by individuals. In practical application scenarios, a seamless transition between efficient cooling and heating is achieved by simply flipping the film. More importantly, the DMH film combining the benefits of composites demonstrates portability, durability, and easy-cleaning, promising to achieve large-scale production and use of thermally managed textiles in the future. The energy savings offered by film applications provide a viable solution for the early realization of carbon neutrality. 展开更多
关键词 Micro-nanofiber film DUAL-MODE comfortable thermal management Simplified production UTILITY Energy saving
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Numerical Prediction of Ride Comfort of Tracked Vehicle Equipped with Novel Flexible Road Wheels
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作者 Yaoji Deng Zhiyue Wang +3 位作者 Youqun Zhao Junjie Gong Hui Shen Fen Lin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第4期277-289,共13页
Enhancing ride comfort has always constituted a crucial focus in the design and research of modern tracked vehicles,heavily reliant on the driving system's performance.While the road wheel is a key component of th... Enhancing ride comfort has always constituted a crucial focus in the design and research of modern tracked vehicles,heavily reliant on the driving system's performance.While the road wheel is a key component of the driving system,traditional road wheels predominantly adopt a solid structure,exhibiting subpar adhesion performance and damping effects,thereby falling short of meeting the demands for high-speed,stable,and long-distance driving in tracked vehicles.Addressing this issue,this paper proposes a novel type of flexible road wheel(FRW)characterized by a catenary construction.The study investigates the ride comfort of tracked vehicles equipped with flexible road wheels by integrating finite element and vehicle dynamic.First,three-dimensional(3D)finite element(FE)models of both flexible and rigid road wheels are established,considering material and contact nonlinearities.These models are validated through a wheel radial loading test.Based on the validated FE model,the paper uncovers the relationship between load and radial deformation of the road wheel,forming the basis for a nonlinear mathematical model.Subsequently,a half-car model of a tracked vehicle with seven degrees of freedom is established using Newton's second law.A random road model,considering the track effect and employing white noise,is constructed.The study concludes by examining the ride comfort of tracked vehicles equipped with flexible and rigid road wheels under various speeds and road grades.The results demonstrate that,in comparison to the rigid road wheel(RRW),the flexible road wheel enhances the ride comfort of tracked vehicles on randomly uneven roads.This research provides a theoretical foundation for the implementation of flexible road wheels in tracked vehicles. 展开更多
关键词 Ride comfort Flexible road wheel Finite element model Dynamic model Tracked vehicle
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Impact of Varying Blower Opening Degrees on Indoor Environment and Thermal Comfort
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作者 Shengqiang Shi Abdelatif Merabtine +1 位作者 Rachid Bennacer Julien Kauffmann 《Fluid Dynamics & Materials Processing》 EI 2024年第8期1703-1716,共14页
At present,air handling units are usually used indoors to improve the indoor environment quality.However,while introducing fresh air to improve air quality,air velocity has a certain impact on the occupants’thermal c... At present,air handling units are usually used indoors to improve the indoor environment quality.However,while introducing fresh air to improve air quality,air velocity has a certain impact on the occupants’thermal comfort.Therefore,it is necessary to explore the optimization of air-fluid-body interaction dynamics.In this study,the indoor air flow was changed by changing the opening and closing degree of the blower,and the thermal manikin is introduced to objectively evaluate the human thermal comfort under different air velocities.The main experimental results show that the air change rate increases with the increase of the opening and closing degree of the blower considering an ACH(air changes per hour)range between 3.8 and 10.For a better prediction,a linear correlation with a coefficient of 0.995 is proposed.As the blower’s opening is adjusted to 20%,25%,30%,35%,and 40%,the air velocity sensor positioned directly beneath the air inlet records average velocities of 0.19,0.20,0.21,0.28,and 0.34 m/s over four hours,respectively.Observations on thermal comfort and the average sensation experienced by individuals indicate an initial increase followed by a decline when the blower’s operation begins,with optimal conditions achieved at a 35%opening.These findings offer valuable insights for future indoor air ventilation and heat transfer design strategies. 展开更多
关键词 Air handle unit air velocity thermal comfort thermal sensation
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Reinforcement Learning Model for Energy System Management to Ensure Energy Efficiency and Comfort in Buildings
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作者 Inna Bilous Dmytro Biriukov +3 位作者 Dmytro Karpenko Tatiana Eutukhova Oleksandr Novoseltsev Volodymyr Voloshchuk 《Energy Engineering》 EI 2024年第12期3617-3634,共18页
This article focuses on the challenges ofmodeling energy supply systems for buildings,encompassing both methods and tools for simulating thermal regimes and engineering systems within buildings.Enhancing the comfort o... This article focuses on the challenges ofmodeling energy supply systems for buildings,encompassing both methods and tools for simulating thermal regimes and engineering systems within buildings.Enhancing the comfort of living or working in buildings often necessitates increased consumption of energy and material,such as for thermal upgrades,which consequently incurs additional economic costs.It is crucial to acknowledge that such improvements do not always lead to a decrease in total pollutant emissions,considering emissions across all stages of production and usage of energy and materials aimed at boosting energy efficiency and comfort in buildings.In addition,it explores the methods and mechanisms for modeling the operating modes of electric boilers used to collectively improve energy efficiency and indoor climatic conditions.Using the developed mathematical models,the study examines the dynamic states of building energy supply systems and provides recommendations for improving their efficiency.These dynamic models are executed in software environments such as MATLAB/Simscape and Python,where the component detailing schemes for various types of controllers are demonstrated.Additionally,controllers based on reinforcement learning(RL)displayed more adaptive load level management.These RL-based controllers can lower instantaneous power usage by up to 35%,reduce absolute deviations from a comfortable temperature nearly by half,and cut down energy consumption by approximately 1%while maintaining comfort.When the energy source produces a constant energy amount,the RL-based heat controllermore effectively maintains the temperature within the set range,preventing overheating.In conclusion,the introduced energydynamic building model and its software implementation offer a versatile tool for researchers,enabling the simulation of various energy supply systems to achieve optimal energy efficiency and indoor climate control in buildings. 展开更多
关键词 Building energy management building heating system dynamic modeling reinforcement learning energy efficiency comfortable temperature
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