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To investigate the fluid structure of gravity current in backdraft consisted of the hot gas and the ambient air, to predict the ignition time for backdraft and to study the effect of opening geometries on the ignition time.

Numerical models based on large eddy simulation in fire dynamics simulator are adopted to study the ignition time.

The density (temperature) profiles and velocity fields from the numerical simulation show the typical fluid structure of gravity current, i.e. the slightly raised head, the billows formed behind the head and the lobes and clefts at the leading edge. The increased mixing of gravity current by the ceiling opening geometries comparing to the mixing by the end opening geometries is a result of the three‐dimensional flow. The non‐dimensional velocity presented here is independent of the different normalized density differences, and only depends on the different opening geometries. From this result, it is feasible to predict the ignition time for backdraft in a compartment.

This paper provides a method for predicting the ignition time for backdraft, and offers helps for people, especially firefighters, avoid the hazard from backdraft.

The purpose of this paper is to study the combined effects of moisture and radiation on thermal protective performance of protective clothing exposed to low level radiation.

Using a sweating manikin, the effect of radiation and moisture on heat and moisture transfer was initially analyzed under the dry manikin with sweating rate of 100 g/(m2h) exposed to 2.5 kW/m2, and then studied at 200 and 300 g/(m2h) exposed to 2 and 3 kW/m2, respectively. Finally, the combined effects of thermal radiation and moisture were predicted by fitting the relationships among heat loss and wet skin surface temperature, with the sweating rate and radiation intensity.

The results show that the heat loss and the wet skin surface temperature are affected by the combined effects of moisture and radiation, with two distinctly different trends. Heat loss from the manikin is increasing with the sweating rate, and decreasing with thermal radiation intensity. However, the wet skin surface temperature has an opposite situation.

Two filling equations are given to present the relationships among heat loss and wet skin surface temperature, with the sweating rate and radiation intensity. With these two equations, the heat loss and the wet skin surface temperature when exposed to radiation can be predicted by only measuring the mean radiant and ambient temperatures and controlling the sweating rate.

In this issue of the Journal a new series begins which deals with the functions and activities of world‐wide Associations involved in printed circuits. To start the series, an article has been prepared which describes the activities of the European Institute of Printed Circuits (EIPC), and is based on information furnished by that organisation. Due acknowledgement is hereby made to their Executive Director, Dr. Fassini, for his co‐operation and assistance in the production of this article.

The paper aims at the bi‐objective optimization of a two‐echelon distribution network model for facility location and capacity allocation where in a set of customer locations with demands and a set of candidate facility locations will be known in advance. The problem is to find the locations of the facilities and the shipment pattern between the facilities and the distribution centers (DCs) to minimize the combined facility location and shipment costs subject to a requirement that maximum customer demands be met.

To optimize the two objectives simultaneously, the location and distribution two‐echelon network model is mathematically represented in this paper considering the associated constraints, capacity, production and shipment costs and solved using hybrid multi‐objective particle swarm optimization (MOPSO) algorithm.

This paper shows that the heuristic based hybrid MOPSO algorithm can be used as an optimizer for characterizing the Pareto optimal front by computing well‐distributed non‐dominated solutions. These aolutions represent trade‐off solutions out of which an appropriate solution can be chosen according to industrial requirement.

Very few applications of hybrid MOPSO are mentioned in literature in the area of supply chain management. This paper addresses one of such applications.

The purpose of this paper is to analyze the influence of underwear on the microenvironment of human clothing.

Based on the basic laws of energy and mass conservation, the paper combined the theory of heat and mass transfer to establish the simulation of the influence of underwear on human thermal reaction in microclimate and prediction model of human thermal reaction law.

The impact on the microenvironment affected by tighter underwear is less than the effect of loose underwear and computational flow dynamics (CFD) can accurately predict the thermal reaction parameters’ values of the human body.

It can be effectively used for the prediction of heat exchange between human body and environment in high-temperature environment and human thermophysiological parameters, and overcomes the individual differences of human experiments and the danger and repeatability of high-temperature environmental experiments.

This paper aims to investigate the application of unsupervised machine learning in the international location decision (ILD). This paper addresses the need for a fast, quantitative and dynamic location decision framework.

Unsupervised machine learning technique, i.e. k-means clustering, is used to carry out the analysis. In total, 24 different indicators of 94 countries, categorized into five groups, have been used in the analysis. After the clustering, the clusters have been compared and scored to select the feasible countries.

A new framework is developed based on k-means clustering that can be used in ILD. This method provides a quantitative output without personal subjectivity. The indicators can be easily added or extracted based on the preferences of the decision-makers. Hence, it was found out that the unsupervised machine learning, i.e. k-means clustering, is a fast and flexible decision support framework that can be used in ILD.

Limitations include the generality of selected indicators and clustering algorithm used. The use of other methods and parameters may lead to alternate results.

The framework developed through the research intends to assist the decision-makers in deciding on the facility locations. The framework can be used in international and national domains. It provides a quantitative, fast and flexible way to shortlist the potential locations. Other methods can also be used to further decide on the specific location.

This study aims to identify and rank the operational and financial risks causing a delay in the commencement of the city gas distribution project in India.

This study reviews the literature to identify operational and financial risks variables associated with infrastructure projects. Followed by a survey to isolate and assess the critical risk factors for city gas distribution network project in India. The survey data is evaluated using factor analysis to understand the latent structure of the critical risk factors. Second, the author ranks the identified variables as per significance by using the mean score method.

Five critical risk factors with 20 variables were extracted and assessed to build more understanding of their significance and impact on city gas distribution network project.

This study is the first attempt to follow the management approach to identify and rank operational and financial risks impacting city gas distribution project.

This study aims to identify the operational and financial risks associated with the city gas distribution project in India and suggest appropriate strategies to mitigate them.

This study aims to identify the operational and financial risks associated with the city gas distribution project in India and suggest appropriate strategies to mitigate them. The survey data is evaluated using factor analysis to understand the latent structure of the critical risk factors. Second, the author uses Situation, Actor and Process–Learning, Action and Performance framework to suggest the mitigation strategies for the identified operational and financial risk factors.

The research identified five critical risk factors and suggested 39 mitigation strategies to address operational and risk factors impacting CGD projects. The findings of this research will enable the CGD companies to formulate long-term strategies for their business and adopt proactive measures to mitigate the operational and financial risks causing delay and increasing project costs. This study also highlights the importance of government support in developing a conducive environment for CGD industry to thrive.

The CGD projects are critical for natural gas growth in India’s energy mix. The project delay leads to a rise in the total cost involved and increases the payback period for the CGD companies. To the best of authors’ knowledge, this research is first of its kind that identifies the critical operational and financial risks affecting CGD projects in India and suggests the mitigating strategies for them.

The purpose of this paper is to provide the details of developments to researchers in test apparatus and evaluation methods to rate the thermal protective performance (TPP) of firefighters’ clothing under high-temperature and high-humidity condition.

This review paper describes the influence laws of moisture on thermal protection and the moisture distribution in actual fire environment. Different evaluation methods used for assessing the effect of moisture on the TPP were investigated, with an emphasis on test devices, evaluation indexes as well as their relationship and limitations.

The moisture from the ambient, clothing and human perspiration plays an important role in determining the TPP of firefighter protective clothing. It is obvious that research on moisture-driven heat transfer in firefighter’s clothing system are comparatively little, primarily focussing on pre-wetted methods of multi-layer fabric. Further studies should be conducted to develop more standardized moistening systems and improve the current calculation methods for evaluating the performance of protective clothing. New explorations for heat and moisture transfer mechanism in protective clothing should be investigated.

Protective clothing is the efficient way to provide fire-fighting occupational safety. To accurately evaluate the TPP of protective clothing under high-temperature and high-humidity condition will help to optimize the clothing performance and choose the proper clothing for providing firefighters with the best protection under multiple thermal hazards.

This paper is offered as a concise reference for scientific community further research in the area of the TPP evaluation methods under high-temperature and high-humidity condition.

The purpose of this paper is to study heat and steam transfer in a vertical air gap and improve thermal protective performance of protective clothing under thermal radiation and hot steam.

An experiment-based model was introduced to analyze heat and moisture transfer in the vertical air gap between the protective clothing and human body. A developed test apparatus was used to simulate different air gap sizes (3, 6, 9, 12, 15, 18, 21 and 24 mm). The protective clothing with different air gap sizes was subjected to dry and wet heat exposures.

The increase of the air gap size reduced the heat and moisture transfer from the protective clothing to the skin surface under both heat exposures. The minimum air gap size for the initiation of natural convection in the dry heat exposure was between 6 and 9 mm, while the air gap size for the occurrence of natural convection was increased in the wet heat exposure. In addition, the steam mass flux presented a sharp decrease with the rising of the air gap size, followed by a stable state, mainly depending on the molecular diffusion and the convection mass transfer.

This research provides a better understanding of the optimum air gap under the protective clothing, which contributes to the design of optimum air gap size that provided higher thermal protection against dry and wet heat exposures.