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As aircraft become more dependent on a great variety of electronic equipment, now many times greater than the cabin load, is a growing problem. NGL has investigated a variety of ways of overcoming these problems and has evolved a range of equipment to suit various applications. C. Rootes, Engineering Group Manager—Environmental Control Systems, describes them.

The purpose of this note is to demonstrate, from the aircraft designer's point of view, the difficulties and penalties involved in blast cooling electrical machinery and to discuss briefly methods by which they may be reduced or eliminated.

The purpose of this paper is to study how cryogenic CO₂ cooling during the welding process affects corrosion behaviour of friction stir welding (FSW) AA7010‐T7651.

Friction stir welded AA7010‐T7651 was produced with a rotation speed of 288 rpm and a travel speed of 58 mm/min. The liquid CO₂ was sprayed onto the weld centre line immediately after the toolpiece. The microstructures of welds in different regions were observed using Field Emission Gun Scanning Electron Microscope (FEG‐SEM). The effect on the corrosion susceptibility was investigated using a gel visualisation test and potentiodynamic polarisation measurements using a micro‐electrochemical technique.

The main corrosion region for both FSWs AA7010‐T7651 produced with and without cryogenic CO₂ cooling is in the HAZ region, which exhibited intergranular attack. Cryogenic cooling does not show any influence on anodic reactivity of the weld region (both nugget and HAZ) compared to uncooled weld metal. However, the width of the reactive HAZ is reduced after cooling, as compared to the uncooled weld. The cooled welds show higher cathodic reactivity in the nugget region than does the nugget region of uncooled welds.

There has been no previous work to investigate the effect of cryogenic CO₂ cooling on the corrosion behaviour of FSW AA7010‐T7651. The paper relates the microstructures of both uncooled and cooled welds to their anodic and cathodic reactivities using a micro‐electrochemical technique.

Examines the hazard analysis critical control point system (HACCP) for maintaining the microbiological quality of foods. In particular, it deals with the cooling of foods and uses the Heisler model to predict the cooling effects of various types of cooling equipment on different types of food.

The Hong Kong government agencies launched a “Cooling Vest Promotion Pilot Scheme” across four industries, namely, construction, horticulture and cleaning, airport apron services, and kitchen and catering industries in 2013. A follow-up questionnaire survey regarding this innovative heat stress controlling measure was administered to evaluate its applicability to these industries. The paper aims to discuss these issues.

The questionnaire surveys were separately administered to frontline workers and management staff. A total of 232 workers from the four industries participated in the full-scale questionnaire survey (A), which aimed to evaluate the perceived effectiveness of cooling vests, worker satisfaction, and willingness to wear cooling vests. The survey was also geared toward eliciting the comments of the workers regarding logistics-related issues. A total of 100 members of the management staff across the four industries participated in the questionnaire survey (B), which aimed to solicit their feedback about the Pilot Scheme and the logistic arrangements for using cooling vests.

On the basis of the survey results, a systems model was established. The model revealed that the applicability of cooling vests mainly depends on the perceived benefits (i.e. worker satisfaction) and logistic costs. The results implied that the existing personal cooling vest failed to satisfy the workers’ needs and incurred potential logistic costs, which likely limited the broad application of cooling vests.

The current study employed a systematics thinking approach and provided practical recommendations that could benefit industrial practitioners in the extensive application of an innovative heat stress precautionary measure.

The design of wing lower tension surfaces is considered as an illustration of the general principles.

The single-supplier multi-retailer cold chain is a widely adopted type of supply chain in the real-world food industry. This paper aims to consider the problem of effectively designing and managing a single-supplier multi-retailer cold chain for fresh produce with deterministic demand to minimize the total cost, which includes cooling, loss of value and carbon emission costs.

The global stability index (GSI) method and the non-Arrhenius model are integrated to describe the behavior of food quality degradation. The power-of-two (PoT) policy is adopted in determining the coordinated replenishment policies for the suppliers and retailers, and an appropriate wholesale price structure that can achieve the coordination of the chain is presented.

The properties of the cold chain are uncovered, and an appropriate wholesale price scheme that achieves chain coordination with the optimal PoT decision is provided. In the numerical examples, different scenarios are investigated, and it is found that the cold chain parameters influence the optimal decisions in certain ways.

The PoT policy – an efficient policy to determine the replenishment strategy – has not been adopted in finding the solution of a single-supplier multi-retailer cold chain in the literature. Also, no study has compared the uncoordinated and coordinated cold chain. Moreover, in the existing literature, the wholesale price is usually a constant rather than having a coordinated scheme. This research aims to fill these research gaps.

This study aims to deal the numerical simulation on buoyant convection and energy transport in an inclined cubic box with diverse locations of the heater and coolers.

The left/right walls are cooled partially whereas the other walls are kept adiabatic. In the left/right walls, three different locations of the cooler are examined, whereas heater moves in three locations in the middle of the enclosed box. The governing models are numerically solved using the finite-element method.

The simulations are done on several values of the Rayleigh number and cavity inclination angles and different locations of the heater and coolers. The results are presented in the form of streamlines, isosurfaces and Nusselt numbers for different values of parameter involved here. It is recognized that the inclination of the box and the locations of the coolers strongly influence the stream and energy transport inside the enclosed domain.

The present investigation is conducted for steady, laminar, three-dimensional natural convective flow in a box for different locations of cooler and tilting angles of a cavity. The study might be useful to the design of solar collectors, room ventilation systems and electronic cooling systems.

This work examines the effects of different locations of cooler and tilting angles of a cavity on convective heat transfer in a 3D cavity. The study is useful for thermal engineering applications.

The US Environmental Protection Agency’s (EPA’s) ENERGY STAR Buildings Program was established in the early 1990s as a means for building owners and managers to improve the energy performance of their facilities, while simultaneously reducing the amount of pollution emitted into the atmosphere from power plants. The programme outlines a five‐stage approach to improving the energy efficiency of existing buildings to help control rising energy costs. The five stages include lighting upgrades, building tune‐up, load reductions, air distribution system upgrades and HVAC plant upgrades. Each stage is designed to build on the success of the previous stages. Today, the EPA recognises buildings that perform in the top 25 per cent in terms of energy efficiency through the ENERGY STAR Label for Buildings. This paper describes the five‐stage ENERGY STAR Buildings strategy as well as how a building achieves the status of being ENERGY STAR labelled. Furthermore, this paper demonstrates the potential of the ENERGY STAR Buildings Program through a case study of four office buildings, owned and operated by the Ohio Building Authority. These buildings have each been upgraded, following the EPA’s five‐stage strategy, and each has received the ENERGY STAR Label for Buildings.

THE problem of the dissipation and transfer of heat is one that is becoming of increasing importance in aircraft with the introduction of gas‐turbines and jet propulsion as well as in view of the prospects of flight at high altitudes. We are therefore printing below summaries of all the papers read at the recent Anglo‐American conference on the subject, although some of them are not directly concerned with aeronautical applications.