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The purpose of this paper is to analyse the dynamics of a thermal field generated in a tubular bus with rated current by using two models of electrical resistivity of copper.

The boundary-initial problem of the modified heat equation was formulated for the tubular bus. Analytical solutions were obtained by means of Green’s functions as the kernels of the integral operator inverse to the corresponding differential operator. The results were presented graphically and verified using the finite element method. The calculations were made by considering the example of the Storm Power Components tubular bus (USA).

Analytical field models were used to determine time- and space-variable heating curves, time constants and steady-state current ratings.

This paper is related to the structure of a hollow cylinder. Other bus sections can be taken into account by using the coordinate systems of different curvilinear orthogonal symmetry.

Using the analytical method, the influence of the variable (temperature dependent) electrical resistivity on some important parameters and characteristics of the tubular bus was investigated. The system was considered as an element with distributed parameters.

A UK manufacturer of tubular steel chairs is operating a robot welding cell that has increased its productivity by 30%. Also, product changeover times can be accomplished in two to three minutes.

This paper describes models of micro‐turbines and fuel cells, which can be used in stability studies.

The plants models derived are based on the main equations. These models are developed in the Laplace domain and transient simulation is done using a software developed based on the MATLAB package.

The micro‐source is capable of providing effective load‐following service in the distribution system. However, the results also show that the micro‐source is not an uninterruptible power supply and does not protect the load from voltage instability while in grid‐connect mode. When a micro‐turbine plant is connected to a point where it gives support to a load in fault conditions, the lower the inertia of micro‐turbine plant, the greater is the destabilizing tendency for faults in the distribution system. On the other hand, transient stability is enhanced with aid of the SOFC inverter.

The effects of these micro‐sources on the network performance are shown and a distribution system embedded with the micro‐sources is used as an example. Finally, transient stability and voltage stability of the system are investigated.

The purpose of this paper is to obtain a better insight into the impact of atmospheric corrosion in Mauritius by investigating the corrosion prevention strategies used in the country and determining the related costs.

Companies and organizations, in various industrial sectors, affected by atmospheric corrosion were selected. They were inspected and surveys were performed in order to fulfill the aim of the study.

It has been observed that extensive atmospheric corrosion problems have been encountered in the capital city, leading to the use of a range of corrosion prevention methods. However, carbon steel, which corrodes easily, is very commonly used in the country. This leads to the wide use of alkyd‐based barrier coatings. The cost of atmospheric corrosion has been found to be equal to 0.38 per cent of the GDP.

This study is expected to raise concern on the problem of atmospheric corrosion in Mauritius and the related waste in materials.

This study is expected to help in adopting corrosion prevention policies and strategies in Mauritius.

THE Trident IE fuel system, designed to operate on cither kerosene or JP.4, has a straightforward layout with few controls. Five integral tanks (FIG. 1), comprising four in the wings and one in the centre section, give a total of 5,880 Imp. gall, of which 2,000 Imp. gall, are contained in the centre tank. (Total fuel capacity of the Trident 1C is 4,960 Imp. gall, with 1,160 Imp. gall, in the centre tank.) Each wing inner tank has slightly more than twice the capacity of the outer.

The ecological footprint represents a simple way to assess the amount of materials consumed and waste produced by a given entity. The approach has been applied to countries, towns, households, and more recently university campuses. One of the challenges of using the ecological footprint at a university is the difficulty of determining how large the footprint should be. The authors have developed a calculator specific to the needs of a university campus, and applied it to the University of Toronto at Mississauga (UTM). Rather than focus on the overall size, the purpose of this paper is to instead create several scenarios to help communicate the relative impacts of alternative actions.

An ecological footprint calculator appropriate to the campus was developed and applied to UTM. Three scenarios were then created: on‐campus electricity generation versus electricity purchased from the grid, current commuting patterns versus those expected if a student bus pass is adopted, and use of virgin office paper versus recycled office paper.

The results of the calculator suggest that energy consumption represents the largest component of UTM's footprint, followed by commuting to campus.

The relative benefits of on‐campus electricity generation, increasing public transit use, and the adoption of recycled paper are all highlighted through the scenario calculations.

This paper presents a way to avoid the difficulty of determining how large a university's footprint should be through the use of an alternative scenario method, which provides an easy way to communicate the impacts of consumption decisions to a campus' community.

In this article the requirement leading to the design is discussed and this is followed by a general description of the aircraft and its operating efficiency. The accommodation is described, with particular reference to the flight deck and equipment. The various systems and installations are next reviewed; followed by a detailed description of the various structural components, which, in many cases, have been designed round these systems. The development work that has been done in order to allow design and construction to be completed will be described in some detail in a later article.

October 11, 1967 Negligence — Electricity — Unguarded electric wires — Electrician required to tighten wires — Mobile electric crane in course of construction — Not practice to guard wires — Whether absence of guard negligence — Electrician requiring to remove any guard to carry out work — Statutory duty — Duty to safeguard electric conductor — Fall while descending scaffolding — Whether “reasonably practicable” to guard wires — Whether employers in breach of statutory duty — Electricity Regulations, 1908 (S.R.&O. 1908, No. 1312), reg.2.

THE work described in this paper is part of a programme concerned with the plastic, creep, and relaxation properties of metals under complex stress systems at elevated temperatures.which is being carried out in the Engineering Division of the N.P.L. It comprises data on the criterion of departure from elastic behaviour, of a low carbon steel over the temperature range 20–550 deg. C, and of an aluminium alloy over the temperature range 20–200 deg. C, and the creep properties under complex stress systems of the low carbon steel at 350 deg. C, and of the aluminium alloy at 150 and 200 deg. C.

This comprises a pump on each engine either of which draws air through the gyro‐operated instruments via a change‐over cock (dash‐starboard) and Plessey 215B adjustable relief valves, set to 5 in. Hg. on forward face of each firewall. The suction gauge is on the port side of the dash. If an automatic pilot is fitted, it is connected to the discharge from the port pump, otherwise the pumps exhaust into an oil drain collector box at the bottom of each firewall.