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Recent studies have found that the high demand for air-conditioning usage in tropical countries has affected the thermal adaptability of building occupants to hot weather, and increased building energy consumption. This pilot study aims to investigate the effects of transient thermal environment changes on participants' sensory and physiological responses.

The change of thermal perceptions, skin temperatures and core temperatures when exposed to transient thermal environments (cool-warm-cool) from 10 college-aged female participants during a simulated daily commute by foot to class in a tropical university campus were investigated. Subjective measurements were collected in real-time every 5 min.

The main finding suggests that participants were acclimatised to cool air-conditioned indoor environments, despite exhibiting significant mean skin temperature differences (p < 0.05). In addition, exposure to uniform air conditioning from 17 to 18°C for 20 min was thermally unacceptable and reduced concentration during given tasks.

The study focused on thermal comfort conditions in a uniform air-conditioned lecture hall, and the findings may not be applicable for residential and other private building spaces. The distinct temperature difference between indoor and outdoor in the tropical built environment resulted in high dependence on air-conditioning usage. The building occupants' well-being and energy conservation implications of the findings are discussed.

This study provides the platform for discussion on the dynamics of occupants' comfort level and adopting a more variable thermal environment in tropical spatial transient thermal environments among architects and building management system managers. The findings from this study may contribute to the Malaysian Standards for Energy Efficiency and Use of Renewable Energy for Non-Residential Buildings (MS1525).

A knowledge gap in adaptive thermal comfort due to exposure from transient conditions in tropical university campus for energy efficiency revision has been investigated.

The physical environment comfort in a workplace is claimed to be vital, as it will encourage healthier, more productive and lower absenteeism rate among employees. The purpose of this paper is to investigate the importance of physical environment comfort and establish its relationship with employees’ performance and productivity.

Evaluation for the selected case studies is made in the aspects of employee’s comfort perceive health and absenteeism rate by wielding the elements of physical comfort consisting room temperature, relative humidity and illuminance level. Field study and questionnaire survey were carried out for three institutional building particularly management department. Spearman’s correlation analysis was conducted to establish the relationship between the physical environment comfort and health symptoms faced by the employees.

Correlations were found between room temperature, lighting and relative humidity with health-related issues such as feeling stuffy, getting tired easily and facing difficulty in concentration which affect employees’ productivity and work performances. In addition, it was proven that the overall physical environment comfort factors have an impact on employees’ health which indirectly affects their absenteeism rate. The average absenteeism rate was compared between the case studies as well.

Performance and productivity for universities’ office employees are very essential in ensuring that the universities run smoothly and support teaching, innovation, learning and research activities. This study attempts to establish the relationship between physical environment comfort and universities’ office employees’ performance and productivity.

Maintaining a comfortable physical environment in the workplace is claimed to be vital as it will create a “healthier” building with optimum environmental conditions, which enable employees to be healthier and have a lower absenteeism rate, and hence be more productive. Thus, the purpose of this paper is to deal with the importance of physical environment comfort in the office workplace. Evaluation was made of the office workers’ performance that is mainly affected by levels of comfort in the office.

Three selected case studies were evaluated based on aspects of employees’ comfort, perceived health and absenteeism rate, by considering the elements of physical comfort that consist of room temperature, relative humidity and luminance level. The selected case studies were the Department of Development and Estate Maintenance of three research universities in Malaysia. Field studies were carried out using hygrometers and lux meters in measuring the said elements as well as post-occupancy evaluation, which involved 30 respondents for each case (total 90 respondents), to determine their perception of comfort and its effect on their health and absenteeism rate. Data collected were analysed using Statistical Package for the Social Sciences.

The results suggest that employees did not find luminance level uncomfortable, when compared with room temperature, thus proving that employees are more sensitive to room temperature comfort. Furthermore, when the room temperature comfort was low, significant correlations were found with health-related issues such as feeling “stuffy”, being easily tired and having difficulty concentrating.

This paper investigates the relationship between employee performance and a comfortable workplace environment. It could be concluded that an uncomfortable environment in an office workplace leads to health-related issues as well as increasing the absenteeism rate. High levels of employee absenteeism lead to decreased employee productivity, therefore affecting their work performance.

Heat gain in buildings occurs due to heat transfer through the building fabric or envelope, especially the walls and roof. The purpose of this paper is to identify and recommend the suitable wall materials for better thermal performance in buildings in warm and hot climatic zones of India. As India lies between the tropic of cancer and the equator, the solar radiation from the sun falls more on the walls than the roofs of the buildings. Thus, it is imperative to protect the walls from heat gain to promote thermal comfort in naturally ventilated buildings and reduce the energy loads due to artificial cooling systems in air-conditioned buildings.

In this paper, an investigation of heat flow characteristics in steady-state and the transient state for five different uninsulated wall structures using computational fluid dynamics (CFD) software has been carried out. The climate conditions at Madurai, India have been considered for this study.

The findings of the study revealed that aerated autoclaved concrete (AAC) and hollow clay blocks (HCB) for external walls in naturally ventilated buildings in warm climatic regions could improve the building’s thermal performance index and reduce peak indoor operative temperature by about 6°C–7°C. The results of steady-state and transient state analysis were found to be in good agreement with the results of the reviewed literature.

Over the past few decades, only very few architects and builders have been successful in influencing their clients to accept alternate materials such as AAC blocks, HCB, stabilized earth blocks, adobe blocks, fly-ash bricks as an alternate to conventional bricks in an attempt of highlighting their benefits, such as; materials that are easily available, more energy-efficient, can withstand the extreme weather conditions, promote thermal comfort and cost-effective. This paper provides strong evidence that AAC and HCB blocks are the most appropriate materials for improving the thermal performance of envelope walls in regions where the outdoor temperatures are above 40°C.

This paper has made an attempt to identify the appropriate wall materials for effective thermal performance in warm and hot climates. A comparative analysis between five different wall types under the existing solar conditions has been analyzed using CFD simulation study in steady-state and transient conditions under summer conditions and the appropriate wall materials have been suggested. There has been no attempt carried out so far to analyze the thermal performance of different walls using 24 h transient approach in CFD.

The purpose of this paper is to quantify occupant satisfaction levels within Leadership in Energy and Environmental Design (LEED)-certified higher education buildings and determine the extent to which this certification helps designers to deliver successful interior environments.

A web-based adaptation of the Center for the Built Environment's (CBE) Occupant indoor environmental quality Survey was distributed within two LEED-certified higher education buildings at a public university. Occupants were then asked to participate in interviews designed to contextualize survey results and further understand issues identified by building users. Descriptive statistics and a content analysis were utilized to determine satisfaction levels in each building.

In general, LEED certification may be used as an aid for delivering successful interior environments, however, opportunities for enhancing the reliability of this tool were identified. For example, while Building A and Building B exceeded the CBE standards, neither met the 80 percent thermal comfort satisfaction rating recommended in the LEED system. Interviewees identified thermal set points, lack of thermal controls, and cold material finishes as the culprits. Based on study findings and supporting literature, suggestions are made for improving the LEED certification process and integrating post-occupancy evaluations (POEs) into the development of higher education buildings.

This study's findings may shed some light on how LEED certification and POEs aid in the production of exemplary higher education facilities. This study helps to inform sustainable practices in higher education settings and serve as a foundation for continued research in the field of sustainable design.

In this paper, the thermal contact comfort of a suddenly wetted shirt and some selected mechanical parameters of ten various woven shirt fabrics were measured with the aim of determining the effect of their composition on their complex quality level. In order to explain the thermal contact comfort of superficially wetted shirts, a new parameter called moisture absorptivity was introduced and a simple equation of the moisture transfer between the fabric and skin was derived. Since the direct measurement of the moisture absorptivity is complicated, an indirect method for its experimental determination was described and used for evaluation of thermal comfort. As regards the final complex evaluation of the measured shirt fabrics, it was found that shirts containing 25‐40 per cent of classical PES fibres blended with cotton, compared with non‐treated pure cotton shirts, have shown similar or even better water vapour permeability, fairly warmer feeling in dry state, better shear, fairly better ability to keep the form and a bit lower moisture absorptivity (worse thermal contact comfort feeling in the case of superficial wetting). Moreover, thermal comfort properties may be still improved by the application of special modified PES fibres.

This paper traces the evolution of objective measurement of textile hand and comfort from Pierce through modern methodology and approaches. Special emphasis is given to discuss the contribution of the Kawabata Evaluation System (KES) towards advancing the state of objective measurement. Laboratory case studies are used to show how data generated by the KES and other instruments can be integrated into a comprehensive approach that attempts to explain human comfort response to garment wear in terms of fabric mechanical, surface and heat and moisture transfer properties.

The purpose of this paper is to investigate the heat transfer on an alpine‐climbing mitt featuring an electrical heating multilayer, in order to provide information for the optimization of its thermal performance.

A numerical model was developed to simulate the heat transfer across an electrical‐heated alpine mitt. The model was used to study the heat losses as a function of the environmental conditions, to optimise the positioning of the heating elements, to determine the optimal power input to the heating system, to estimate the battery capacity requirements and to assess the effect of low‐emissivity surfaces.

The results show that: the heating elements assure approximately constant temperatures across the skin provided they are not more than 6‐7 mm apart; the use of low‐emissivity surfaces facing the skin can reduce the total heat loss by 8‐36 per cent (for air layer thicknesses in the range 10⁻³ to 10⁻² m) and to increase the skin temperature during the transient operation of the heating multilayer; the heat losses from the mitt are practically independent of the chosen heating power; and a battery capacity of 4 A h assures active temperature regulation for more than 18‐23 h.

By enhancing the thermal performance of an electrical heating mitt, the use of low‐emissivity surfaces (facing the skin) can favour the thermal comfort perception of its user.

The influence of several parameters on the thermal performance of an electrical‐heated mitt is analysed and discussed. The findings are relevant for improving the performance of existing electrical heating garments.

To examine the role of predicted mean vote (PMV) in air‐conditioned environments by conducting a thermal comfort study.

A formal statistical approach was adopted for the credibility of the study. Thermal measurements and questionnaire filling were carried out in commercial offices to collect the required data. Statistical analysis on the collected data and logical reasoning were then employed to derive the conclusions.

Provide an evidence to support PMV to be an appropriate thermal comfort index in air‐conditioned environments. Guarantee high productivity of occupants by using PMV in air‐conditioning control.

Future research work should be carried out to investigate any significant relationship between improvement in PMV and the profits gained by occupants inside an air‐conditioned space. With such relationship, it is possible to develop an intelligent air‐conditioning control to yield the most cost‐effective thermal environments for commercial offices.

Air‐conditioning engineers are highly recommended to employ PMV to assess the thermal comfort environment in air‐conditioned offices.

This paper highlights the importance aspect on choosing a thermal comfort index for comfort assessment in air‐conditioned offices. The index itself should not consider adaptive actions. Otherwise, the productivity of occupants would be severely deteriorated. It is well known that PMV is the thermal comfort index that can fulfill this requirement.

In experiments utilising sweat solution and distilled water, seamed ensembles performed less thermally efficiently than unseamed fabrics.

Water may not accurately reflect perspiration when testing multi-layered clothes for thermal comfort in wet state. Most researchers used water or sodium chloride (NaCl) to measure wet state thermal comfort. However, human perspiration is an extremely complex mixture of aqueous chemicals, including minerals, salts, lipids, urea and lactic acid. This study compares the effects of simulated sweat solution to distilled water on the thermal behaviour of a multi-layered fabric assembly with different seam patterns.

Experiment results show that stitching decreases thermal resistance and thermal conductivity. Seam pattern of 10 cm diagonal spacing is more thermally resistant than 2.5 cm diagonal spacing. In comparison to that of simulated sweat, fabric that has been moistened with distilled water exhibits increased thermal conductivity. Hollow polyester wadding or micro polyester wadding as the intermediate layer exhibits greater thermal resistance than multi-layered construction with spacer fabric as middle layer.

This study considers human perspiration while designing protective clothing for wet thermal comfort.