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Heat stress, having caused preventable and lamentable deaths, is hazardous to construction workers in the hot and humid summers of Hong Kong. The purpose of this paper is to develop a heat stress model, based on the Wet Bulb Globe Temperature (WBGT) index.

Field studies were conducted during the summer time in Hong Kong (July to September 2010). Based upon 281 sets of synchronized meteorological and physiological data collected from construction workers in four different construction sites between July and September 2010, physiological, work‐related, environmental and personal parameters were measured to construct and verify the heat stress model.

It is found that drinking habit, age and work duration are the top three significant predictors to determine construction workers' physiological responses. Other predictors include percentage of body fat, resting heart rate, air pollution index, WBGT, smoking habit, energy consumption, and respiratory exchange rate. The accuracy of the model is verified against data which have not been used in developing the model. The accuracy of the heat stress model is found to be statistically acceptable (Mean Absolute Percentage Error=5.6 percent, Theil's U inequality coefficients=0.003).

Based on these findings, appropriate work‐rest pattern can be designed to safeguard the well being of workers when working in a hot and humid environment.

The model reported in this paper provides a more scientific and reliable prediction of the reality which may benefit the industry to produce solid guidelines for working in hot weather.

Raise in temperatures due to climate change is likely to increase the heat stress in occupations that are physically exerting and performed outdoors which might potentially have adverse health and productivity consequences. The purpose of this paper is to estimate the productivities in construction work under the influence of heat stress using the predicted mean vote (PMV) index.

Field studies were conducted during May 2014 which is summer time in Chennai. Continuous heart rate of workers and wet bulb globe temperature measurements are conducted for workers engaged in different jobs in construction. Metabolic rates and the workload of the workers from heart rate were calculated using the ISO method 8996 and the PMV values are calculated using the tool developed by Malchaire based on the method ISO 7730. Direct observations and personal interviews were conducted to substantiate the productivity estimations.

The results showed that workers working outdoors with moderate and heavy workload exceeded the threshold limit value of 28°C and had adverse productivity impacts (18-35 per cent productivity loss), whereas the workers engaged in light indoor work was not affected by heat stress and consequent productivity losses. The productivity estimations using the PMV index is found to be statistically significant for three types of construction works (Pearson correlation coefficient value of −0.78) and also correlated well with the observations and self-reported productivities of the workers.

The method used in this paper provides a scientific and reliable estimation of the productivities which may benefit the industry to set realistic project completion goals in hot weather and also implement interventions and policies to protect workers’ health. Developing adaptive strategies and implementing control measures are the need of the hour to protect worker’s health and economic losses in the face of climate change.

The purpose of this paper is to outline some key aspects such as material systems used, phenomenological and statistical process modeling, techniques applied to monitor the process and optimization approaches reported. All these need to be taken into account for the ongoing development of the SLM technique, particularly in health care applications. The outcomes from this review allow not only to summarize the main features of the process but also to collect a considerable amount of investigation effort so far achieved by the researcher community.

This paper reviews four significant areas of the selective laser melting (SLM) process of metallic systems within the scope of medical devices as follows: established and novel materials used, process modeling, process tracking and quality evaluation, and finally, the attempts for optimizing some process features such as surface roughness, porosity and mechanical properties. All the consulted literature has been highly detailed and discussed to understand the current and existing research gaps.

With this review, there is a prevailing need for further investigation on copper alloys, particularly when conformal cooling, antibacterial and antiviral properties are sought after. Moreover, artificial intelligence techniques for modeling and optimizing the SLM process parameters are still at a poor application level in this field. Furthermore, plenty of research work needs to be done to improve the existent online monitoring techniques.

This review is limited only to the materials, models, monitoring methods, and optimization approaches reported on the SLM process for metallic systems, particularly those found in the health care arena.

SLM is a widely used metal additive manufacturing process due to the possibility of elaborating complex and customized tridimensional parts or components. It is corroborated that SLM produces minimal amounts of waste and enables optimal designs that allow considerable environmental advantages and promotes sustainability.

The key perspectives about the applications of novel materials in the field of medicine are proposed.

The investigations about SLM contain an increasing amount of knowledge, motivated by the growing interest of the scientific community in this relatively young manufacturing process. This study can be seen as a compilation of relevant researches and findings in the field of the metal printing process.

A theoretical study is performed to investigate transport phenomena in channel flows under uniform heating from either both side walls or a single side. The anisotropic t^2¯− ε_t heat‐transfer model is employed to determine thermal eddy diffusivity. The governing boundary‐layer equations are discretized by means of a control volume finite‐difference technique and numerically solved using a marching procedure. It is found that under strong heating from both walls, laminarization occurs as in the circular tube flow case; during the laminarization process, both the velocity and temperature gradients in the vicinity of the heated walls decrease along the flow, resulting in a substantial attenuation in both the turbulent kinetic energy and the temperature variance over the entire channel cross section; both decrease causes a deterioration in heat transfer performance; and in contrast, laminarization is suppressed in the presence of one‐side‐heating, because turbulent kinetic energy is produced in the vicinity of the other insulated wall.

Personal protective clothing (PPC) enables people to work in hazardous environments, but PPC can have a detrimental effect on worker performance. Predicting garment effects on worker performance is difficult because quantitative relationships among garment properties and human responses are not known. Presents a systematic structure for studying the relationships among garment properties and their immediate effects on the worker. Using a survey of 118 studies, previous work was categorized according to garment parameters and dependent measures. Except for studies of heat stress, most of these studies compared competing garments or simply measured physiological response, rather than relating these effects to garment attributes. Such results are seldom transferable to other clothing systems or tasks. Proposes a conceptual model based on this systematic structure. Introduces garment impediment indices (GIIs) as response functions of garment attributes, and offers an approach for developing quantitative models of PPC effects on worker performance.

Hot and humid climates (HHCs) are potential environmental hazards that directly affect construction workers' health and safety (HS) and negatively impact workers' productivity. Extensive research efforts have addressed the effects of HHCs. However, these efforts have been inconsistent in their approach for selecting factors influencing workers in such conditions. There are also increasing concerns about the drop-off in research interest to follow through intrusive and non-real-time measurements. This review aims to identify the major research gaps in measurements applied in previous research with careful attention paid to the factors that influence the intrusiveness and selection of the applied data collection methods.

This research integrates a manual subjective discussion with a thematic analysis of Leximancer software and an elaborating chronological, geographical and methodological review that yielded 701 articles and 76 peer-reviewed most related articles.

The literature included the physiological parameters as influencing factors and useful indicators for HHC effects and identified site activity intensity as the most influencing work-related factor. In total, three main gaps were identified: (1) the role of substantial individual and work-related factors; (2) managerial interventions and the application of the right time against the right symptoms, sample size and measurement intervals and (3) applied methods of data collection; particularly, the intrusiveness of the utilised sensors.

The focus of researchers and practitioners should be in applying nonintrusive, innovative and real-time methods that can provide crew-level measurements. In particular, methods that can represent the actual effects of allocated tasks are aligned with real-time weather measurements, so proactive HHC-related preventions can be enforced on time.

This review contributes to the field of construction workers' safety in HHCs and enables researchers and practitioners to identify the most influential individual and work-related factors in HHCs. This review also proposes a framework for future research with suggestions to cover the highlighted research gaps and contributes to a critical research area in the construction industry.

Extreme hot environments are prevalent in many occupational settings, and facilities management workers are no exception. Wearing suitable cooling garment is a useful means to alleviate heat strain and improving performance at heat exposure. This paper aims to evaluate the effectiveness and applicability of the cooling vest across four selected fields (i.e. construction, outdoor cleaning and horticulture, kitchen work and work involved manual handling at the airport) and identify the shortcomings of the cooling vest used by the participating workers.

This study adopted a two-phase design: a quantitative questionnaire survey followed by qualitative in-depth interviews.

A remarkable physical strain alleviation (PSA) of 21.1 per cent (14.8 per cent in construction, 18.8 per cent in horticulture and cleaning, 27.4 per cent in kitchen and catering and 26.5 per cent in airport apron service) is achieved by the use of cooling vest in four industries. Despite the success of PSA, several shortcomings of the cooling vest were identified: easily stained color, heavy weight, short cooling time, inflexibility that presents a hazard around moving equipment, lack of industry-specific design, nondurable and thick fabric with poor permeability.

The findings of the current study do not only confirm the effectiveness of the cooling vest in alleviating heat strain and physical strain but also identify the major shortcomings upon which further improvements can be made.

The problem of stress is increasingly gaining attention in the construction industry in recent years. This study is aimed at examining the causes, effects and possible alleviation of stress of project management (PM) practitioners so that their stress could be appropriately managed and reduced, which would contribute to improved mental health.

Primary data were collected in an online questionnaire survey via Qualtrics. Questions ranged from PM practitioners’ stressors, stress and performance under stress to stress alleviation tools and techniques. One hundred and five PM practitioners completed the questionnaire. Their responses were compiled and analyzed using descriptive statistics, correlation and regression.

The results confirmed that the identified stressors tended to increase stress of PM practitioners. All stressors tested in this study were found to have negative impact on the performance of PM practitioners. In particular, the burnout stressors were seen as the key stressors that influence the performance of PM practitioners and have a strong correlation with all the other stressors. It was also found that a number of tools and techniques can reduce the impact of stressors on PM practitioners.

This study has taken a specific focus on stress-related issues of PM practitioners in the construction industry due to their critical role in this project-dominated industry. Using the Job Demand-Resource theory, a holistic examination was not only conducted on stress and stressors but also on alleviation tools and techniques. This study has thus made significant contribution to the ongoing research aimed at finding solutions to mental health-related problems in the project-dominated construction industry, thereby achieving the United Nations’ social sustainability development goals.

Video is an increasingly important medium for the communication of ideas in academia. It has high potential as a tool in instruction and is valuable for the visual portrayal of the outcomes of large‐scale mathematical models and simulations. A major problem for conventional video is that it is a passive medium, moving linearly at a fixed pace regardless of the viewer. This problem is overcome when video documents are made interactive so that the viewer can affect the pace and order of viewing. Video controlled by computer software permits the user to select video segments for viewing in any order and see video segments in the context of text, computer graphics, and sound. In effect, one can read a book (on screen) where the photographs are video segments, and one can branch from any page to any other as interest dictates. We might call such materials compound documents and the method of delivering them a multimedia presentation. Libraries have begun to collect interactive video materials and to sustain the equipment necessary to make the documents useful to readers. The challenge to library managers is making sensible decisions about investments in this arena.

The purpose of this paper is to compare the evaporative resistance and thermal insulation of clothing measured by thermal manikin “Walter” using uniform and non-uniform skin.

The non-uniform skin with different perspiration rates was made by laminating a silicone layer on the inner side of a uniform skin. The thermal manikin was then covered with prepared non-uniform skin as well as uniform one. Four types of clothing ensembles were tested.

The relative intensity of perspiration rate was realized in different part of “Walter” skin, which was close to the perspiration rate of human being. There was a strong correlation between uniform skin and non-uniform skin. The thermal insulation and evaporative resistance of clothing measured on the non-uniform skin were higher than the ones determined on the uniform skin. However, their moisture permeability index showed the reversed tendency.

The implication of the research is to investigate the differences between uniform skin and non-uniform skin for manikin “Walter.” This is possibly useful in correcting and predicting more accurate thermal insulation and evaporative resistance of clothing measured by “Walter” with a uniform skin in future.

It was more accurate using non-uniform skin in evaluating thermal and wet comfort comparing to uniform skin.