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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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Comfort义齿粘附剂的体外细胞毒性评价 被引量:4
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作者 赵克 程祥荣 +1 位作者 高燕 韩光丽 《华西口腔医学杂志》 CAS CSCD 北大核心 2004年第2期162-164,共3页
目的 评价作者自行研制的新型Comfort义齿粘附剂 (Comfort_DA)的体外细胞毒性。方法 Comfort_DA置于细胞培养液 72h制备出材料的浸提液 ,用同一培养液再稀释为 5 0 %、75 %浓度后分别加入含人口腔成纤维细胞悬浮液的培养板中 ,其中空... 目的 评价作者自行研制的新型Comfort义齿粘附剂 (Comfort_DA)的体外细胞毒性。方法 Comfort_DA置于细胞培养液 72h制备出材料的浸提液 ,用同一培养液再稀释为 5 0 %、75 %浓度后分别加入含人口腔成纤维细胞悬浮液的培养板中 ,其中空白对照组仅加入新鲜培养液。 3块培养板分别继续在 5 %CO2 、37℃培养箱内开放培养2d、3d和 4d后 ,四唑盐比色法观察细胞的活性以研究细胞增殖率 ,用分光光度计以 4 90nm波长测光密度值 (OD) ,组间方差分析并评定该材料的毒性级。结果 空白对照组、Comfort_DA的 5 0 %和 75 %浓度组间OD值的差别有显著性意义 (P <0 0 5 ) ;各组浓度Comfort_DA的毒性程度为“0~ 2”级。结论 作者所研制的新型Comfort_DA仅有较轻微的细胞毒性。 展开更多
关键词 comfort义齿粘附剂 体外细胞毒性 comfort-DA 四唑盐比色法 DA 牙周膜
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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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Evaluation model of individual thermal comfort based on mean skin temperature 被引量:10
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作者 刘蔚巍 连之伟 邓启红 《Journal of Southeast University(English Edition)》 EI CAS 2010年第2期254-257,共4页
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
关键词 thermal comfort mean skin temperature Mahalanobis distance discrimination method THERMOREGULATION
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Field survey of indoor thermal comfort in rural housing of northern China in heating season 被引量:3
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作者 黄莉 朱颖心 +1 位作者 欧阳沁 曹彬 《Journal of Southeast University(English Edition)》 EI CAS 2010年第2期169-172,共4页
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
关键词 rural housing thermal comfort field survey space heating
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Comfort义齿粘附剂抑制白色念珠菌生长的实验研究 被引量:2
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作者 赵克 程祥荣 李颖 《华西口腔医学杂志》 CAS CSCD 北大核心 2005年第2期177-177,共1页
关键词 comfort义齿粘附剂 抑制白色念珠菌生长 实验研究 真菌感染 西地碘
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Field measurements on thermal comfort of a building with double-skin faade in winter 被引量:1
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作者 王芳 张小松 +2 位作者 李舒宏 朱文运 胡渠 《Journal of Southeast University(English Edition)》 EI CAS 2010年第2期292-296,共5页
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
关键词 thermal comfort field measurement double-skin faade
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