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The purpose of this study was to investigate the psychological response to changes in temperature and humidity near the skin, and the psychological factors of thermal discomfort.

The experiments involved changing the temperature and humidity from a neutral to a hot-humid environment, and vice versa, every 30 min. The psychological response to temperature (which ranged from 24 to 40°C) and humidity (which ranged from 30 to 80% relative humidity) was investigated.

The sensory scores shifted according to the direction of the change in temperature and humidity. The environment seemed to be evaluated relatively, whereby the sensory perception was dependent on the prior thermal environment. The psychological response to changes in temperature and humidity near the skin tended to shift from simple situational perceptions, such as feeling hot, to stifling and uncomfortable perceptions, and finally to the perception of dullness. Examining the psychological components revealed that the uncomfortable feeling was affected by “stifling” and “sweaty” perceptions with increasing temperature, by “stifling”, “sweaty”, and “sticky” perceptions with decreasing temperature, by “stifling”, “dull”, “sticky”, and “hot” perceptions with increasing humidity, and by “sweaty”, “dull”, and “humid” perceptions with decreasing humidity.

This study identified the psychological response that accompanies changes in temperature and humidity near the skin, as well as the psychological components of discomfort associated with changes in temperature and humidity. These results provide insights into the microclimate and thermal comfort of clothing.

The purpose of this paper is to evaluate the corrosion of silver due to hydrogen sulphide pollutant in indoor conditions at a microelectronics plant located in Mexicali, Baja California, a semi‐arid zone in the northwest of Mexico.

Silver coupons and silver plated on to copper‐lead frames are exposed in the assembly process building of a microelectronics company during a period of 60 days and also in a sheltered test chamber that simulates indoor conditions with ambient concentrations of atmospheric pollutants, temperature and relative humidity (rH). Other exposures are made in the test chamber to study the corrosion behaviour of silver coupons over a duration of 24 months. The corrosion products were analysed using the Scanning Electron Microscope (SEM) and Energy Dispersive X‐ray Spectroscopy (EDS). Corrosion rates were measured by Quartz Crystal Microbalance (QCM) under laboratory‐controlled conditions.

The presence of silver sulphide corrosion products, dendrites and whiskers is observed on the exposed samples using SEM and EDS analysis.

The paper is designed to establish whether the company, where the exposure is taking place, constituted an indoor environment with outdoor hydrogen sulphide pollutant in sufficient concentration to induce silver corrosion.

The methodology used in this work can be applied to study the indoor corrosion behaviour of other metals, which will be of interest to the microelectronics industry.

The remarkably wide field of current corrosion research in the United States was strikingly shown at the recent annual meeting of the National Association of Corrosion Engineers in Chicago. Over 40 papers were given on such topics as corrosion principles, underground corrosion, protective coatings, cathodic protection, resistant metals, plastics, plant, etc. Symposia were arranged on such subjects as pipeline coatings, corrosion by water, the refinery industry, elevated temperature corrosion, oil and gas production, and protective coatings. Here are summaries of the papers presented.

Solder has been the primary method of component attachment since the early days of radio. This tradition carries with it an overhead which becomes increasingly expensive as the degree of miniaturisation increases. Solderless interconnect methods, however, are often overlooked or unfairly discounted as unreliable. Surprisingly, solderless connections can be mechanically superior to and environmentally more robust than their soldered peers. This paper reviews various solderless interconnect techniques for surface mount applications and discusses their relative merits.

The purpose of this paper is to investigate the influence and relationship of segment area and opening area in segmented protective pad in comparison to non-segmented pad to the energy absorption and performance attributes relevant to thermophysiological wear comfort.

The compressive stress-strain curves were obtained using Instron Tester and were used to analyse the energy absorption of the pads and the segmented pad assemblies. The dry thermal resistance and evaporative resistance of the non-segmented and segmented protective pads were obtained using MTNW Sweating Guarded Hot Plate.

The compression test results and performance attributes relevant to thermophysiological wear comfort test result demonstrated that the area segment and opening area of segmented pad influenced their energy absorption value, dry thermal resistance value and evaporative resistance value (permeability index value).

The results are expected to be useful for design and engineering of hip impact protective garments. Hip impact protective pads are used to prevent hip fractures in elderly people as a result of fall.

The mechanical and tribological properties of polymers and polymer composites vary with different environmental conditions. This paper aims to review the influence of humidity/water conditions on various polymers and polymer composites' mechanical properties and tribological behaviors.

The influence of humidity and water absorption on mechanical and tribological properties of various polymers, fillers and composites has been discussed in this paper. Tensile strength, modulus, yield strength, impact strength, COF and wear rates of polymer composites are compared for different environmental conditions. The interaction between the water molecules and hydrophobic polymers is also represented.

Pure polymer matrices show somewhat mixed behavior in humid environments. Absorbed moisture generally plasticizes the epoxies and polyamides and lowers the tensile strength, yield strength and modulus. Wear rates of PVC generally decrease in humid environments, while for polyamides, it increases. Fillers like graphite and boron-based compounds exhibit low COF, while MoS2 particulate fillers exhibit higher COF at high humidity and water conditions. The mechanical properties of fiber-reinforced polymer composites tend to decrease as the rate of humidity increases while the wear rates of fiber-reinforced polymer composites show somewhat mixed behavior. Particulate fillers like metals and advanced ceramics reinforced polymer composites exhibit low COF and wear rates as the rate of humidity increases.

The mechanical and tribological properties of polymers and polymer composites vary with the humidity value present in the environment. In dry conditions, wear loss is determined by the hardness of the contacting surfaces, which may not effectively work for high humid environments. The tribological performance of composite constituents, i.e. matrix and fillers in humid environments, defines the overall performance of polymer composite in said environments.

The purpose of this paper was to study the relationship between safe storage life and storage mode of hot-rolled sheet (Q235, X70) in humid environment, and a prediction model of safe storage life under different storage modes was established.

The corrosion behavior of hot-rolled sheets under different storage conditions was studied with immersion experiment and morphology observation.

The results show that pitting occurs on the hot-rolled sheets in humid environment, and the corrosion behavior is strongly related with the storage mode. When they are stored separately, the number and depth of pits first increase and then decrease as the Cl⁻ concentration rises, while for the stack storage, pit depth increases with increasing Cl⁻ concentration. The safe storage time of separate storage is longer than that of stack storage. Based on this, a model of chloride ion concentration and storage life was established.

A storage safe life model of hot-rolled sheet in humid environment is proposed.

The purpose of this paper is to focus on the ongoing discourse centred on enhancing building performance to provide an interpretation of life cycle cost (LCC) analysis, directly applicable to building construction in coastal areas located in tropical wet–humid settings.

A survey of 50 buildings based on physical observation is carried out to identify typical failure patterns in wet‒humid environment. Further, a comparative initial construction cost and LCC analysis is computed for two alternative building schemes with identical floor plans: Scheme A using sound construction and detailing to guard against future maintenance problems and Scheme B adopting the typical designs evident in the study area.

The result of the analysis shows that in the long-run scheme, A is an economically more viable option than B, as the increased initial costs are entirely offset by the reduced running cost.

The contextual nature of LCC analysis poses difficulties in applying the evidence provided in this study to provide a generalisable financial justification to buildings clients.

The outcome of the study provides analytical validation to overcome resistances and enables informed decision making by clients, which is necessary to promote transition from conventional to environmentally responsive design choices suitable to wet–humid conditions.

The study provides an interpretation of LCC analysis, directly applicable to building construction in the tropical wet–humid setting of coastal areas against the backdrop of inconsistencies in the practical application of the theory of LCC.

The paper aims to determine the thermal comfort perception of schoolchildren from a warm and humid environment. There is a concern about the effect of high temperature on the health and academic performance of schoolchildren.

Objective and subjective methodological approaches were adopted to collect data during the fieldwork in the selected primary schools. ASHRAE adaptive comfort model was adopted to analyze the data.

The paper provided empirical results about the comfort requirements of schoolchildren from the warm and humid environment. During the occupied school time, the studied schoolchildren were found to tolerate temperatures higher than the upper limit temperature recommended by ASHRAE Standard 55. The paper recommends that the studied children may not need any active ventilator to be thermally comfortable during the occupied school hours

The paper found the range of temperatures that schoolchildren from the warm and humid environment can adapt to. The information may be useful to architects, engineers and facility managers