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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.

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.

The purpose of this study is to determine the temperature ratings of infant bedding.

Mathematical models were developed for predicting temperature ratings of infant bedding for all age groups based on the thermal balance equation. These models were validated by the published physiological data and the baby manikin tests. The air temperature was compared with the predicted temperature rating, and the skin temperature of infant or baby manikin was used to explain the validation results.

The models had higher prediction accuracy, especially for the infant bedding with uniformly distributed thermal insulation. The results showed that an increase of 1 clo in thermal insulation caused a decrease of 4.2–6.0 °C in temperature rating. The slope of the model reduced with the increasing month-age, indicating that an older infant had a lower temperature rating than a younger infant.

Suggestions were given for caregivers that younger infants ought to be covered with more bedding than adults; however, older infants were expected to require less bedding.

The outcomes provided scientific guidelines on the selection of bedding for infants at a particular room temperature to ensure the health and safety of infants.

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.

Fire safety of a building is becoming a prominent consideration due to the recent fire accidents and the consequences in terms of loss of life and property damage. ISO 834 standard fire test regulation and simulation cannot be applied to assess the fire performance of 3D printed concrete (3DPC) walls as the real fire time-temperature curves could be more severe, compared to standard fire curve, in terms of the maximum temperature and the time to reach that maximum temperature. Therefore, this paper aims to describe an investigation on the fire performance of 3DPC composite wall panels subjected to different fire scenarios.

The fire performance of 3DPC wall was traced through developing an appropriate heat transfer numerical model. The validity of the developed numerical model was confirmed by comparing the time-temperature profiles with available fire test results of 3DPC walls. A detailed parametric study of 140 numerical models were, subsequently, conducted covering different 3DPC wall configurations (i.e. solid, cavity and rockwool infilled cavity), five varying densities and consideration of four fire curves (i.e. standard, hydrocarbon fire, rapid and prolong).

3DPC walls and Rockwool infilled cavity walls showed superior fire performance. Furthermore, the study indicates that the thermal responses of 3DPC walls exposed to rapid-fire is crucial compared to other fire scenarios.

To investigate the thermal behaviour, ABAQUS allows performing uncoupled and coupled thermal analysis. Coupled analysis is typically used to investigate combined mechanical-thermal behaviour. Since, considered 3DPC wall configurations are non-load bearing, uncouple heat transfer analysis was performed. Time-temperature variations can be obtained to study the thermal response of 3DPC walls.

At present, there is limited study to analyse the behaviour of 3DPC composite wall panels in real fire scenarios. Hence, this paper presents an investigation on the fire performance of 3DPC composite wall panels subjected to different fire scenarios. This research is the first attempt to extensively study the fire performance of non-load bearing 3DPC walls.

This paper was read before the World Petroleum Congress on July 19, 1933. Mr. Pye acted as chairman of a committee set up by the Institution of Petroleum Technologists to investigate the corelation of knock‐rating as determined in a test engine with the results obtained using aero‐engine cylinders. This paper prepared by him summarises the results of the committee's investigations

The paper presents an alternative solution to address part obsolescence. This paper discusses approaches to solve part obsolescence including an uprating approach. This paper also describes the methods to uprate parts, and demonstrates the practical application of the uprating approach in the form of a case study.

This paper has been written to provide an understanding of the uprating approach to mitigate the problems caused by part obsolescence. The paper discusses the challenge faced due to part obsolescence, the temperature ratings for electronic parts, the uprating methods and finally explains the use of uprating to mitigate part obsolescence in the form of a case study. The part being uprated is a microcontroller unit used in many avionics applications. The case study describes a particular use of uprating and the return on investment.

Based on the uprating approach, it was discovered that for the particular application, the commercially available plastic quad flat pack microcontroller could be used as a substitute for the “military” ceramic BGA version, which was discontinued by the manufacturer. It was discovered that there would be no problem with the commercial part's quality or reliability for the particular application. Parametric tests showed no evidence of instability of electrical characteristics over the uprated temperature range. There was substantial return on investment due to the use of uprated parts.

This paper can help electronics manufactures deal with part obsolescence. This paper demonstrates the practicality of uprating parts. Uprating can save companies money by reducing the need for life‐time buys, substitution of parts and even redesign.

The paper provides an alternative approach to address the problem of part obsolescence. This paper shows that proper uprating leads to cost saving while continuing to provide reliable service.

The paper aims to present an advanced 2 D transient heat transfer analysis capable of accounting for the effect of spalling in terms of amount, location and time. The model accounts for moving thermal boundary conditions to comply with the changing member cross section. The discussed numerical model provides a tool to quantify the effect of spalling on the flexural capacity of reinforced concrete beams.

The implementation of the presented numerical model in an in-house code and its validation has been discussed. The thermal subroutine has been sequentially coupled with the mechanical subroutine (sectional-analysis) to compute the variation of sectional moment carrying capacity with exposure time.

The temperatures predicted while considering spalling were in good agreement with experiments available in literature. The presented results also emphasise the importance of considering the time of spalling. The results also show that the fire rating of simply supported beams is also affected by spalling in the compression zone.

It should be acknowledged that the model does not predict spalling, rather is developed as a tool to study the effect of spalling. The model takes the information related to spalling in terms of the location, amount and time, as user input.

The paper quantitatively presents the effect of spalling on the predicted temperature variation across the beam cross section and the moment carrying capacity.

The purpose of this paper was to investigate whether small holes in an impermeable patch at the wrist improve perceived comfort during exercise.

Nine male participants participated in this study. During the experiment, participants cycled 60 W in a hot room (35°C, 30 percent relative humidity) while an impermeable 20 cm² patch was located on the ventral side of one wrist and at the same time a patch of identical shape with 5 mm diameter holes (17.7 percent uncovered) on the other wrist. The participants could not see the patches. Participants were forced to choose which patch they perceived as more comfortable. Chest and arm skin temperature, thermal comfort, thermal sensation and wetness perception were assessed.

Participants preferred 5 mm holes over no holes (p=0.017). Chest skin temperature (p=0.018) but not arm skin temperature correlates with this preference. Thermal comfort, thermal sensation and wetness perception did not differ significantly between patches. It is concluded that patches with 5 mm holes are preferred over impermeable patches during work in the heat in particular when the torso skin is warm.

The wrist is a preferred location for smart wearables. Generally, wrist bands are made of air-impermeable materials leading to sensation of wetness and discomfort. This study has shown that manufacturers should consider to make small holes in their wrist bands to optimize wearing comfort.