Comfort Evaluation Method Research Articles

A Case Study on Structural Serviceability Subjected to Railway-Induced Vibrations at TOD Developed Metro Depot

As a sustainable mode of metro-development strategy, transit-oriented development (TOD) is rapidly growing to finance the transport infrastructure investment. The main negative consequence of constructing residential buildings directly over metro depots is railway-induced vibration, that may affect structural serviceability. The residents may feel uncomfortable, as the metro trains start running very early in the morning and finish daily operations very late at night. In order to evaluate the level of human comfort subject to the special situation, a case study was provided in this paper. Directed by the academic review, there were four common comfort evaluation methods, with difference indexes to describe the influence of vibrations. Therefore, a measurement campaign was conducted and both acceleration and velocity sensors were simultaneously installed at the same measurement points, to reduce the influence of the conversion accuracy. The results show that there are certain differences between the evaluation methods in assessing the vibration comfort, but considering the most adverse effects together, the over-track building at this particular TOD-developed depot can ensure that 90% of the occupants would not be highly annoyed by the vibrations. The main negative effect on human comfort at the TOD depot is that the high-level vibrations would cause interruptions in sleep. Among them, the vibrations in this case would affect the rest of 17% of the occupants in the bedrooms on the seventh floor, and make it difficult for 9% of the occupants to fall asleep. Therefore, the evaluation index was suggested to consider more factors related to sleep difficulties and awake threshold values.

Thermal response and thermal comfort evaluation of the split air conditioned residential buildings

In China, split air conditioned (SAC) buildings operate in manual changeover mixed-mode (MM) that integrates air conditioned (AC) mode and natural ventilation (NV) mode in summer. In order to understand the thermal response of such buildings and determine the thermal comfort evaluation method, 522 data were collected from residential buildings in Jiaozuo. In summer, occupants in AC mode had a cooler thermal history than in NV mode because the mean operative temperature in AC mode was lower than in NV mode. And the occupants in AC mode felt cooler, drier, windier, more comfortable and had greater acceptability than occupants in NV mode, but the upper limit of 80% acceptable temperature was close, about 30 °C. Short-term indoor thermal history mainly affects thermal sensation and thermal preference, while perceived control mainly influences thermal comfort and thermal acceptability. The different operating modes in summer have no significant influence on the thermal adaptive ability of occupants, so the thermal comfort of SAC buildings could be evaluated as a whole. When the outdoor temperature is below 30 °C, occupants can take advantage of physiological, psychological and behavioral adjustments to improve their thermal comfort, so adopting the adaptive model for evaluation is recommended. However, when the outdoor temperature exceeds 30 °C, the above adaptative opportunities are limited, and the upper limit of acceptable temperature for occupants is 30 °C. This study promotes the understanding of the impacts of different operating modes on thermal response, and provides support for the thermal comfort evaluation of SAC buildings.

Thermoacoustic environment comfort evaluation method based on facial micro-expression recognition

At present, subjective questionnaire surveys and physiological parameters measured are mainly used to collect the comprehensive response of humans to the environment, evaluating the environmental comfort subjectively and objectively. However, some measuring instruments make people feel uncomfortable and interfere with the natural state of the human body. Some measuring instruments are too bulky to carry. In addition, the changes in physiological parameters are not synchronized with the changes in human feeling, and there is a lag phenomenon, which cannot immediately reflect the human body current feeling. This study considers that the facial expression is an expression form of human emotion, psychology, and brain activities. When touch, hearing, vision, taste, and smell are stimulated by external factors, the facial expression will change. In view of this, this study examines the thermoacoustic environmental comfort based on facial micro-expression recognition. Firstly, the facial micro-expression database based on environment comfort (FMEEC) is constructed. Secondly, a convolutional neural network (CNN) is used to build the micro-expression recognition model (MERCNN). Finally, the MERCNN model is trained to converge with training and verification samples. The micro-expression images collected in the artificial climate chamber and classroom environment are used to test the model's performance. The evaluation results of the MERCNN are compared with the results of subjective questionnaires and the predicted mean vote (PMV) model. The results show that the MERCNN can accurately evaluate the thermoacoustic environment comfort through face micro-expression recognition.

Comfort Assessment of Human-Induced Vibration of Pedestrian Bridges Based on Stevens Annoyance Rate Model

In recent years, the continuous innovation in terms of using new materials and structures for pedestrian bridges has led to a significant reduction in the natural frequency of such bridges. Thus, the human-induced vibration comfort of bridges has been increasingly affected. Therefore, this paper introduces the Stevens annoyance rate model (ARM) and proposes a design and evaluation method for human-induced vibration comfort of pedestrian bridges based on this model. In order to verify the effectiveness of the proposed method, a practical pedestrian bridge is used as an example to perform dynamic analysis, comfort evaluation, and vibration reduction design. The results show that the pedestrian bridge comfort evaluation method based on the Stevens-ARM can accurately quantify the vibration comfort of the human body under uncertainties. For comfort control, the new comfort design method and a genetic algorithm (GA) can arrange multiple tuned mass dampers (MTMDs) more reasonably, which can prevent the annoyance rate (AR) and comfort rate under the two-way coupled vibration from exceeding the limit. Moreover, data obtained from 14 pedestrian bridges in China were analyzed to verify the generality and reliability of the findings.

A measurable evaluation method of visual comfort in underground space by intelligent sorting and classification algorithms

Based on human perception and machine learning methods, this study proposes a measurable method for evaluating visual comfort in underground spaces. First, a comfort evaluation index based on the characteristics of human visual perception is proposed, and color features and segmentation extraction methods for intelligent methods are given. Then, using probability statistics and machine learning methods, a multi-class intelligent sorting and classification algorithm for ranking visual comfort levels is constructed and a comparison is made of the suitability of different intelligent methods for evaluating visual comfort. The random forest algorithm is then selected as the most effective measurable intelligent evaluation algorithm for underground spaces. Finally, the proposed method is compared to intelligent methods employed by previous research, and a case study, the Wujiaochang underground space in Shanghai, China, is applied as the background. Results show that the proposed method can effectively improve the quantification and refinement of human perception and evaluation of comfort in underground spaces; this method will also be useful in computer-aided generative design in the future.

Evaluation of tractor driving vibration fatigue based on multiple physiological parameters.

The vibration generated by tractor field operations will seriously affect the comfort and health of the driver. The low frequency vibration generated by the engine and ground excitation is similar to the natural frequency of human organs. Long term operation in this environment will resonate with the organs and affect drivers’ health. To investigate this possibility, in this paper we carried out a collection experiment of human physiological indicators relevant to vibration fatigue. Four physiological signals of surface electromyography, skin electricity, skin temperature, and photoplethysmography signal were collected while the subjects experienced vibration. Several features of physiological signals as well as the law of signal features changing with fatigue are studied. The test results show that with the increase of human fatigue, the overall physiological parameters show the following trends: The median frequency of the human body surface electromyography and the slope of skin surface temperature decreases, the value of skin conductivity and the mean value of the photoplethysmography signal increases. Furthermore, this paper proposes a vibration comfort evaluation method based on multiple physiological parameters of the human body. An artificial neural network model is trained with test samples, and the prediction accuracy rate reaches 88.9%. Finally, the vibration conditions are changed by the shock-absorbing suspension of a tractor, verifying the effectiveness of the physiological signal changing with the vibration of the human body. The established prediction model can also be used to objectively reflect the discomfort of the human body under different working conditions and provide a basis for structural design optimization.

Optimization analysis of dynamic characteristics of a certain car seat with rigid-flexible coupling

Aiming at the problem of the dynamic comfort of a certain car driver’s seat, from the aspect of selecting the dynamic parameters of the seat cushion, a simulation idea for studying the dynamic comfort of the seat has been proposed. The rigid-flexible coupling dynamics model of the human body and the seat is established through the flexible processing of the seat cushion. ADAMS has been used to analyze the dynamics of the model and compare the changes in the human comfort level when the dynamic parameters of the seat cushion are changed. The optimal range for selecting its dynamic parameters has been obtained. ADAMS/Car has been used to establish a virtual model of the vehicle system, and the dynamic comfort of the model has been analyzed to obtain the human body acceleration power spectral density curve. The results indicate that the optimal selection ranges for seat cushion stiffness and damping are 14∼20N/mm and 0.3∼0.6Ns/mm, respectively. In this range, the resonance frequency of the car seat is lower than the most sensitive frequency of the human body. Use the human comfort evaluation method to verify that the result is reliable, it provides a direction for the subsequent design.

Comfort evaluation of bridge based on stochastic process theory

Vehicle or pedestrian loads can cause bridge vibration. The pedestrian load is essentially a stochastic process, and the vibration response of pedestrian bridges is also a stochastic process. In order to evaluate the human comfort of a pedestrian bridge comprehensively, this paper presents a comfort evaluation method based on stochastic process theory. The autocorrelation function of the displacement response of a pedestrian bridge under random pedestrian load is derived in this paper. On this basis, the root mean square (RMS) of acceleration is proposed as the comfort evaluation index. Taking an asymmetric single-tower cable-stayed bridge as an example, the modal analysis of the bridge is proceeded by finite element method (FEM). Then the acceleration time histories of four measuring points are obtained by fi eld experiment. FEM results and fi eld experiment results are used to analyse random vibration of the bridge. Through a fi eld experiment and random vibration analysis of the bridge, the acceleration peak value evaluation index and the RMS of acceleration value evaluation index are compared. The results show that the RMS of acceleration index is more comprehensive and reasonable because it considers the whole-time history of the vibration response. The RMS of acceleration index is based on stochastic process theory, so it is more rigorous in mathematical expression and clearer in physical concept. It provides a reference for the evaluation of pedestrian bridge comfort.

Investigation of outdoor thermal sensation and comfort evaluation methods in severe cold area

Comfortable outdoor environment benefits the health of citizens and reduces energy consumption and pollution. This study discusses different outdoor thermal sensation and comfort evaluation methods in severe cold area. The database was from a year-long outdoor thermal comfort survey conducted in Harbin, China. Thermal sensation evaluation was developed using meteorological parameters and three popular thermal comfort indices including Standard Effective Temperature (SET*), Physiologically Equivalent Temperature (PET) and Universal Thermal Climate Index (UTCI). Thermal comfort prediction was developed by the three thermal comfort indices and acceptability. Original thermal sensation scales of SET* and PET were less applicable to predict thermal sensation vote (TSV). Calibrated scales of the three indices were obtained based on linear regression results and probit analysis. The accuracies of calibrated scales of thermal sensation were all below 32.8%. The comfortable thermal sensation range in severe cold area varied from “slightly cool” to “hot”. This calibrated range improved accuracies of thermal comfort predicting by around 20%. The unacceptability appropriate to define comfortable range was 9% on the cold thermal sensation side and 26% on the hot side. Adaptation and local exposure also acted on thermal sensation and comfort apart from factors included in thermal comfort indices. Our results provide practical thermal sensation and thermal comfort scales for severe cold area. The discussions indicate the significance of considering adaptation and local exposure for further improving thermal sensation and comfort predicting.

Passengers Comfort Perception and Demands on Railway Vehicles: A Review

Trains are becoming a popular way of transportation driven by comfort and ecology reasons. Latest statistics showed an increasing of 40% on the number of passengers in the last decade. The development of new high-speed trains promoted an evolution on the coaches interiors, as to make railway transportation more attractive. To cope this objective, new requirements were set, namely high levels of comfort and safety. In complement, multiple long-term ride comfort evaluation methods have been developed. The aim of this work is to present a review on the passengers’ comfort perception in railway vehicles. The standards ISO 2631, EN 12299 and the Sperling’s method are the most used ones. They refer several factors, as the vibration (level, frequency and duration), temperature, noise and area of the train per capita. Additionally, the perception of reduced accidents delayed the studies of passive security. Therefore, recent works focus on reducing the consequences of the second impact in case of accident and minimize the biomechanics injury criterion, through new interiors design layouts.
 Keywords: Railway vehicles, Passengers comfort, Posture, Ride evaluation, Passive safety

Study on Comfort Evaluation Methods of Different Women’s High-Heeled Shoes Based on Electroencephalograph (EEG) Technology

Study on Comfort Evaluation Methods of Different Women’s High-Heeled Shoes Based on Electroencephalograph (EEG) Technology

Annoyance-rate-and-casualty-reality-based method of comfort evaluation of military ambulance

The objective of this paper is to explore a new comfort evaluation method, which is suitable for studying the comfort of casualty transported by a military ambulance. The paper applies existing vibration evaluation methods to quantitatively obtain comfort of non-ambulatory casualty, stimulates the patients with different vibrational conditions, and analyses the annoyance rates with psychophysics knowledge as well as the ratio of war to disaster injuries and susceptibility of the wounded. The road test proves that this new method is feasible for vibrational comfort evaluation of non-ambulatory casualty and gains quantitative advantages over the traditional methods.…

Research on Comprehensive Evaluation Method of Ride Comfort of Armored Vehicles

Aiming at the poor ride comfort of an armored vehicle when driving on off-road, which affects badly the working efficiency of the crew members, the current standards of the ride comfort evaluation method were analyzed, and a comprehensive ride comfort evaluation method for multiple states was proposed considering different speed and road surface conditions. The experimental study on ride comfort of two vehicles was conducted. The test results show that vehicle #1 has better ride comfort performance compared with vehicle #2, and the proposed method can effectively guide the comprehensive evaluation of the ride comfort of armored vehicles, which is suitable for the comparative test of the ride comfort performance of armored vehicles.

Evaluation of the thermal comfort for its occupants inside a vehicle during summer

Thermal comfort of occupants from the vehicle environment has gained more importance in the last decades because time spent by people in the vehicles is increasing. During each trip, driver’s thermal comfort must to be ensured to reduce both thermal stress (thus reduces the risk of accidents) and for a healthy state of the occupants. Given the fact that the vehicle environment is non-uniform and fast transient, and because the actual standard (ISO 14505) proposes comfort evaluation methods developed for the steady state conditions in buildings, the purpose of the study is to evaluate a vehicle environment using the three standardised method presented in the above standard. All the three standardized evaluation indices were achieved through standardised methods. The equivalent temperature (teq) index was assessed with an advanced thermal manikin and its values were compared with the survey answers given by people in questionnaires (TSV Thermal Sensation Vote index) and with Predicted Mean Vote (PMV) index values calculated with Comfort Sense standardized evaluation equipment. A first conclusion is that the results of the three evaluation indices are different. Air temperature is different from a zone of the car to another and the thermal evaluation must be done in the place of each passenger.

Momentary discomfort of high-speed trains passing through complex terrain sections under strong wind conditions

Momentary discomfort caused by high-speed trains passing through complex terrain sections under strong wind conditions has become an urgent engineering problem in China. However, few scholars or research institutions have focused on this topic, and there are no standards for the evaluation of such discomfort. Therefore, in this study, the suitability of existing vibration comfort-evaluation methods under strong wind conditions was investigated by a full-scale test, and the characteristics of the car-body vibration and momentary discomfort under strong wind conditions were analyzed. It was indicated that low-frequency transient roll motion and transverse motion of the car-body are the main causes of discomfort, and the comfort-assessment methods in European standard (EN-12299) could not be directly used under these conditions. Consequently, an evaluation method for momentary discomfort caused by high-speed trains passing through complex terrain sections under strong wind conditions is suggested.

Development of gripping comfort evaluation method based on finite element analysis

Development of gripping comfort evaluation method based on finite element analysis

Home Network Monitoring System Based on Internet of Things

With the rapid development of urbanization and the continuous improvement of the quality of life, people pay more and more attention to the monitoring of the home environment to the home environment and life safety. In view of the problems and user needs that are easy to exist in the indoor environment, this paper has carried out Design of home environment monitoring system based on Internet of Things. The system is based on the Internet of Things, with remote viewing and remote alarms, making the monitoring system more comprehensive, networked and remote, ensuring the safety, comfort and health of home life. This paper refers to GB/T18883-2002 indoor air quality standards, based on the basic idea of comfortable home, healthy home, and safe home, designed the overall architecture, and completed the hardware circuit design with this framework, and introduced the overall comfort evaluation method of indoor environment. The main design has completed the monitoring of parameters such as methane, water flow, temperature, humidity, air pressure, dust and formaldehyde. The test results show that the Internet-based home environment monitoring system designed in this paper can realize the monitoring of various environmental parameters and basically meet the design index requirements.

Objective visual comfort evaluation method based on disparity information and motion for stereoscopic video.

In this paper, we propose an objective evaluation method which considers three major factors affecting the visual comfort of viewing a stereoscopic video: the horizontal disparity, the vertical disparity, and the motion. Three experiments are conducted which aim to investigate the effect of three factors on visual comfort. The experimental results show that the visual comfort decreases with increasing the disparity magnitude and motion velocity. Both fast planar motion and depth motion have a negative impact on visual comfort. Finally, we verify the performance of the proposed whole evaluation measure. The experimental results show that the proposed objective evaluation method exhibits good consistency with the subjective evaluation results.

A discussion about thermal comfort evaluation in a bus terminal

Transport stations are distributive hubs composed of transient spaces, often not fully indoor, where most users spend time waiting to travel or waiting for travelers. The aim of this article is to present a comparison between thermal comfort evaluation methods applied in a free running bus terminal located in a mild climate country. Data was collected in field measurements and surveys were performed on 240 passengers, focusing warm season operation conditions. The collected information allowed for the analysis of the comfort conditions of the station according to the following comfort models: PMV-PPD, aPMV, and the adaptive models defined in the ASHRAE 55 and EN 15251 standards. A comparison between the results and the thermal preference (MTP) and the thermal sensation (MTS) expressed in the ISO 10551 subjective scales was performed. It could be concluded that the PMV-PPD and aPMV models overestimated the cooling sensation. The ASHRAE 55 and EN 15251 adaptive approach, although more permissive, still was not totally in line with the thermal sensation of the respondents. An alternative approach based on the correlation between SET* and dissatisfied voters established through the thermal preference method provided a wider comfort range that appears, in this case, to be adequate.

Study on the Evaluation Model of Vehicle Comfort Based on the Neural Network

Due to the subjective perception of the driver, the comfort cannot be described by the objective indexes, meanwhile the normal subjective evaluation methods require plenty of human and material resources. Therefore, in this paper, in order to evaluate the comfort when the vehicle occurs low frequency longitudinal vibration during Tipin/out operations, a comfort evaluation method based on the neural network model is developed. First of all, through the mechanism analysis of the low frequency longitudinal vibration, three basic signals of the objective evaluation are determined. During different Tipin/out operations, the basic signals are collected by the experiment instruments and the subjective evaluation grades are determined by professionals. After that, the basic signals are weighted filtered and transformed into three objective evaluation indexes. Finally, the neural network model is trained by a large number of subjective evaluation grades and the objective evaluation indexes. The comfort performance of the vehicle during Tipin/out operations can be evaluated by the evaluation method.