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A FREQUENTLY recurring problem, more particularly in the sphere of electrical engineering practice, is the determination of the equivalent rating of a machine or piece of apparatus under conditions of intermittent loading. By equivalent rating is to be understood the value of the continuous load, whether expressed in terms of current or power, which will produce the same final temperature rise as is actually produced by the given intermittent load.

Light-Gauge Steel Frame (LSF) structures are popular in building construction due to their lightweight, easy erecting and constructability characteristics. However, due to steel lipped channel sections negative fire performance, cavity insulation materials are utilized in the LSF configuration to enhance its fire performance. The applicability of lightweight concrete filling as cavity insulation in LSF and its effect on the fire performance of LSF are investigated under realistic design fire exposure, and results are compared with standard fire exposure.

A Finite Element model (FEM) was developed to simulate the fire performance of Light Gauge Steel Frame (LSF) walls exposed to realistic design fires. The model was developed utilising Abaqus subroutine to incorporate temperature-dependent properties of the material based on the heating and cooling phases of the realistic design fire temperature. The developed model was validated with the available experimental results and incorporated into a parametric study to evaluate the fire performance of conventional LSF walls compared to LSF walls with lightweight concrete filling under standard and realistic fire exposures.

Novel FEM was developed incorporating temperature and phase (heating and cooling) dependent material properties in simulating the fire performance of structures exposed to realistic design fires. The validated FEM was utilised in the parametric study, and results exhibited that the LSF walls with lightweight concrete have shown better fire performance under insulation and load-bearing criteria in Eurocode parametric fire exposure. Foamed Concrete (FC) of 1,000 kg/m3 density showed best fire performance among lightweight concrete filling, followed by FC of 650 kg/m3 and Autoclaved Aerated Concrete (AAC) 600 kg/m3.

The developed FEM is capable of investigating the insulation and load-bearing fire ratings of LSF walls. However, with the availability of the elevated temperature mechanical properties of the LSF wall, materials developed model could be further extended to simulate the complete fire behaviour.

LSF structures are popular in building construction due to their lightweight, easy erecting and constructability characteristics. However, due to steel-lipped channel sections negative fire performance, cavity insulation materials are utilised in the LSF configuration to enhance its fire performance. The lightweight concrete filling in LSF is a novel idea that could be practically implemented in the construction, which would enhance both fire performance and the mechanical performance of LSF walls.

Limited studies have investigated the fire performance of structural elements exposed to realistic design fires. Numerical models developed in those studies have considered a similar approach as models developed to simulate standard fire exposure. However, due to the heating phase and the cooling phase of the realistic design fires, the numerical model should incorporate both temperature and phase (heating and cooling phase) dependent properties, which was incorporated in this study and validated with the experimental results. Further lightweight concrete filling in LSF is a novel technique in which fire performance was investigated in this study.

This study aims to investigate the heat transfer mechanism of the uniforms used by people working in hot, humid and windy environments. Furthermore, the effectiveness of an opening structure added to the armpit of the uniforms in improving thermal comfort was comparatively examined.

A set of uniforms was tested with the opening at the armpit alternatively zipped or unzipped. Thermal manikin and human tests were performed in a climatic chamber simulating the specific environmental conditions, including wind speeds at four levels (0.15, 0.5, 2, 4 m/s) and relative humidities at two levels (50 and 85%). Static and dynamic thermal insulations of clothing (I_T) were examined by the thermal manikin tests. The human bodies' thermal responses, including heart rates (HR), eardrum temperatures (T_e), skin temperatures (T_sk) and subjective perceptions, were given by the human tests.

Special mechanisms of heat transfer in the specific uniforms used in tropical monsoon climates were revealed. Reductions on I_T were caused by the movement of the human body and the environmental wind, and the empirical equations would underestimate this reduction. The opening at the armpit was able to prompt more heat transfer under dynamic condition, with reducing the I_T by 11.8%, lowering the mean T_sk by 0.92°C, and significantly improving the subjective perceptions (p < 0.05). The heat exhaustion was alleviated with lowering the T_e by 0.32°C.

This study managed to improve the thermal performance of uniforms for workers under unforgiving conditions. The evaluation and design methods introduced by this study provided practical guidance for similar products with strict dress codes and cost control requirements based on the findings from thorough product tests and analysis.

The purpose of this paper is to present the effect of damaged fireproofing on structural steel members. This study will show that a minor damage in fireproofing will reduce the fire rating of members significantly. Damaged fireproofing happens in structures due to various reasons, and the question is always how effective is this fireproofing? This paper presents the results of one type of fireproofing and presents a parametric study on the size of damage and its effect on fire resistance of structural steel members.

The study has been performed using numerical methods, thermal and structural finite element analysis. The analysis method has been verified by experimental results.

Small fire protection damage or loss leads to significant rise of temperature at the damaged parts and causes severe fire resistance reduction of beams. The higher fire protection damage’s extension at the bottom flange of the steel beams does not have any major influence on the rate of reduction of fire resistance of the beams. Steel beams experience greater fire resistance reduction at higher load levels because of the existing of higher stresses and loads within the steel beam section.

The study has been performed using finite element analysis, and it covers a wide range of practical sizes. However, experimental work will be performed by the researchers when funding is granted.

The study provides researchers and practitioners with an estimate on the effect of damaged fireproofing on fire resistance of structural steel beams.

Understanding the effect of the effect of damaged fireproofing helps in estimating the fire resistance of structural steel members, which may protect collapses and disasters.

The research is original; extensive literature review has been performed, and this research is original.

The purpose of this paper is to evaluate the indoor environmental quality among residential buildings in dense urban living environment, after the outbreak of Severe Acute Respiratory Syndrome (SARS), which called for a review on the relationship between health issues and the authors' built facilities.

Environmental tests include thermal comfort, noise, daylight and air quality inside the residence of typical housing units were carried out. Based on inferences drawn from test results, the paper developed systematic conclusions.

It was observed that most of the occupants (over 70 per cent of 125 households) were tolerating the higher air temperature and dimmer daylight inside their residence, which was proven to fall behind Hong Kong Standard. On the contrary, people reflected that they were also trying to abate noise and dust concentration in their daily life.

Owing to the flat occupants' exclusive property rights in law, there were limited access to the residents' flats and only 32 occupants out of 125 allowed us to conduct the survey. Yet, the data set was justified.

The results provides practical guidance for the design of future housing to enhance health and comfort of occupants.

Originality of the findings is based on on‐site data collected in dense urban housing condition. Rating data were also collected from the occupants concerned about their habituation conditions in Hong Kong after the outbreak of SARS, which was a major crisis that called for fundamental review of the authors' built facilities.

To evaluate the effectiveness of ventilation systems in outdoor jackets, two jackets were purchased and modified, one made of PTFE laminated fabric and the other made of polyurethane coated fabric. Six male subjects undertook exercise routines simulating fell walking while wearing these jackets. The skin temperature at four different locations and the amount of perspiration generated during exercise were recorded for analysis. The experimental results were analysed using two‐ way analysis of variance. From the analysis it was found that during the exercise the design of the pit zip openings, especially with pit zip openings at both sleeve and side seams, in a jacket has an effect on thermal regulation, limiting the rate of temperature increase; however, during rest it is the fabric that plays the more important role. The results for the period of exercise suggest that the provision of ventilation at appropriate positions in the jacket could contribute considerably to heat loss irrespective of the use of breathable fabrics.

The purpose of this paper is to ascertain the current affordable apartment dwelling quality attributes, and the preferences of eastern Michigan's urban young and poor, with a view to making recommendations for improvement based on findings.

Data were collected through the questionnaire instrument administered to a representative sample of 32 apartment dwellers. Some ordinal ranking scales were developed and treated in a quantitative manner by assigning ordered Likert scores to them, while others were measured using ratio scales. Spearman rho's correlation and Kruskal–Wallis H test were conducted on the data.

Among the key conclusions, it was observed that the choice to dwell in an apartment may be simply deliberate and a real preference, and not necessarily connected with income, gender or age. The overwhelmingly majority of apartment occupants rejected to pay more for environmentally sustainable apartments.

It is acknowledged that the design of the study, the sample size and statistical methodologies will necessarily limit the accuracy of the results and conclusions based on them. However, they are appropriate and adequate for this level of study. Besides increasing the sample size, further analysis and interpretation of the results are required in future explorations of this research in order to achieve focused and definitive conclusions.

The findings have practical implications for future choices while designing and building apartments that satisfy the health, safety and welfare (HSW) needs of the occupants. Overall, this understanding if implemented may help reduce the rate of turnover among apartment dwellers engendered by dissatisfaction occupants have towards their apartments. At the basic level, this research can initiate a re‐think that would encourage stakeholders to embrace the concept of more suitable, HSW quality‐focused apartments, on realizing and recognizing apartment aspects that most appeal to the urban young and poor who make up a significant proportion of the US population and workforce. This research has the potential to make a significant national impact on the US HSW debate, as it addresses a key stipulation of the Federal housing policy objectives – the Cranston‐Gonzalez National Affordable Housing Act (1990/1998).

This research uncovers salient aspects of apartment that influence the rate of turnover among dwellers engendered by their dissatisfaction with certain apartment features. It reveals apartment aspects that appeal to its urban young and poor occupants.

WHAT a wonderful lady is Dr. Lillian Gilbreth. Whatever her age it can be discounted since years have little or no effect on one so youthful in spirit.

The aim of this paper is to demonstrate the use of historical building performance data to identify potential issues with the build quality and operation of a building, as a means of narrowing the scope of in-depth further review.

The response of a room to the difference between internal and external temperatures is used to demonstrate patterns in thermal response across monitored rooms in a single building, to clearly show where rooms are under-performing in terms of their ability to retain heat during unconditioned hours. This procedure is applied to three buildings of different types, identifying the scope and limitation of this method and indicating areas of building performance deficiency.

The response of a single space to changing internal and external temperatures can be used to determine whether it responds differently to other monitored buildings. Spaces where thermal bridging and changes in use from design were encountered exhibit noticeably different responses.

Application of this methodology is limited to buildings where temperature monitoring is undertaken both internally for a variety of spaces, and externally, and where knowledge of the uses of monitored spaces is available. Naturally ventilated buildings would be more suitable for analysis using this method.

This paper contributes to the understanding of building energy performance from a data-driven perspective, to the knowledge on the disparity between building design intent and reality, and to the use of basic commonly recorded performance metrics for analysis of potentially detrimental building performance issues.

The application of new technologies requires, however, modern rolling mills. Indeed, in manufacturing plants of older types, strict compliance with the developed rolling regimes is not always feasible. Improving the mechanical properties in such cases is possible only by means of cooling. Compressive deformation behavior of carbon–manganese (C-Mn) grade has been investigated at temperatures ranging from 800-900°C and strain rate from 0.01-50 s−1 on Gleeble-3800, a thermo-mechanical simulator. Simulation studies have been conducted mainly to observe the microstructural changes for various strain rate and deformation temperatures at a constant strain of 0.5 and a cooling rate of 20°C s−1.

The project begins with simulation of a hot rolling condition using the thermo-mechanical simulator; this was followed by microstructural examination and identification of phases present by using an optical microscope for hot-rolled coil and simulated samples; grain size measurement and size distribution studies; and optimization of finishing temperature, coiling temperature and cooling rate by mimicking plant processing parameters to improve the mechanical properties.

As the strain rate and temperature increase, pearlite banding decreases gradually and finally gets completely eliminated, thereby improving the mechanical properties. True stress–strain curves were plotted to extrapolate the effect of strain-hardening and strain rate sensitivity on austenite (γ) and austenite–ferrite (γ-a) regions. To validate the effect of strain rate and temperature over the grain size, the hardness of simulated samples was measured using the universal hardness tester and the corresponding tensile strength was found from the standard hardness chart.

The results of the study carried out have projected a new technology of thermo-mechanical simulation for the studied C-Mn grade. These results were used to optimize the plant processing parameter like finishing and coiling temperature and finishing stands strain rate.

By controlling the hot rolling conditions like finishing, coiling temperature and cooling rate, structures differing in mechanical properties can be obtained for the same material. Accurate understanding of a structure being formed when different temperatures are applied enables the control of the process that assures intended structures and mechanical properties are achieved.