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To have a better understanding of the heat transfer mechanisms in a sleeping bag and to investigate the factors influencing thermal resistance of a down sleeping bag.

The mechanism of heat transfer in a sleeping bag was discussed in this paper. The thermal resistances of 24 samples were investigated. Besides, the relation between fill weight and thermal resistance, and that between the air permeability of fabric and thermal resistance, as well as that between down filling rate and thermal resistance were analyzed.

The results showed that thermal resistances of samples varied from 0.35 to 0.8 m² K/W. The fill weight was the most important factor of thermal resistance of sleeping bag and the relation between fill weight and thermal resistance matched well with cubic function. A multiple regression formula was proposed, which with thermal resistance as a dependent variable and with air permeability of fabric, down filling rate, fill weight as independent variables.

Thermal properties of a sleeping bag were analyzed through simplified basic unit under simplified environment conditions, which was necessary for building the first stage of systematic study of thermal performance of a sleeping bag.

As document supply grows in volume and importance it becomes more necessary to measure its performance. Nearly all measures are relative — over time, across countries, and between systems; they should therefore be consistent and comparable. The main measures are: fill rate (broken down by subject, form and date); speed (broken down into the various processes involved in document supply); user satisfaction (because users' needs may not be articulated); and costs. There may be trade‐offs between different measures (eg speed and costs). Any measurement system must be practical. Most data will be collected by sampling, but well designed automated systems in future should enable better measures to be calculated with less effort.

A comprehensive survey of the Southern African Interlending Scheme was undertaken from January 1985 to February 1986. After a brief overview of the scheme and the survey, estimates of the total volume of requests, broken down by countries and types of library, are presented, together with findings relating to fill rates, turnaround times, and the distribution of the interlending volume among member libraries. It was found that interlending traffic was of the order of 300,000 requests in 1985, with a fill rate of 80% and a median turnaround time of 10 days for first requests. University libraries and those in the Pretoria—Witwatersrand—Vereeniging region dominate the traffic, and the concentration of demand on a small number of libraries is cause for concern.

The purpose of this paper is to examine the thermal insulation and water vapor transmission rate (WVTR) according to the type of the filling material, and compared the thermal insulation in the dynamic state considering actual wearing conditions.

The thermal insulation and WVTR were evaluated in a standard state depending on the type of filling material (goose down (GD), duck down (DD), Thinsulate700 (T700), Thinsulate600 (T600) and Polyester (PET)), and the changes in thermal insulation were examined by measuring the microclimate in the case of an environmental change from a high temperature to a low temperature. In addition, the clumping of filling material and the changes in the thickness/weight depending on the laundry process were observed, and the relationships with the thermal insulation were analyzed.

The results showed that for natural filling materials (GD and DD), the thermal insulation deteriorated significantly due to changes in the thickness/weight after laundering ten times, and water washing was more appropriate than the dry cleaning. On the other hand, the artificial filling materials (T700, T600 and PET) showed a relatively smaller difference, except for clumping, when they went through more dry cleaning or water washing cycles compared to the natural filling materials.

The results showed that the laundry methods have different effects on the damage to the filling material, the change in thermal insulation, and the change in the comfort-related physical property. Therefore, it is important to select the optimal laundry method depending on the filling material.

The purpose of this paper is to present models and practical procedures for the analysis of maintenance operations and development of maintenance policies in the context of an oil filling factory. Basic maintenance models, maintenance policy selection and optimum spare part quantity determination procedures are illustrated with a specific case application in a factory.

Maintenance formulas are constructed and applied in a factory to determine down time due to various types of failures and maintenance practices in the system. Based on the analysis of the current system, a new preventive maintenance policy is proposed and its effect on reducing down time due to random failures is estimated by using the formulation developed. Procedures for spare part requirements and optimum order quantities with respect to total costs are outlined for critical spares.

Models and case study results presented in this paper demonstrate that selection of appropriate maintenance policy and optimum spare part order quantities should be based on scientific procedures since the results can significantly affect system performance.

The results obtained in this paper are specific to the case application. However, the models and procedures presented are general and can be applied to any similar problems.

Formulations and procedures outlined in this paper can be used to determine effects of various types of maintenance activities and related policies on system performance. They can be valuable tools for maintenance engineers and operational managers in improving system productivity.

The paper considers a management problem related to maintenance policy selection and spare part order quantity determination in a factory. Detailed procedures outlined in this paper can be highly valuable tools for maintenance managers.

Whereas the Minister of Labour (hereafter in this Order referred to as “the Minister”) has received from the Boot and Shoe Repairing Wages Council (Great Britain) the wages regulation proposals set out in the Schedule hereto;

The purpose of this paper is to show how particle scale simulation of industrial particle flows using DEM (discrete element method) offers the opportunity for better understanding of the flow dynamics leading to improvements in equipment design and operation.

The paper explores the breadth of industrial applications that are now possible with a series of case studies.

The paper finds that the inclusion of cohesion, coupling to other physics such fluids, and its use in bubbly and reacting flows are becoming increasingly viable. Challenges remain in developing models that balance the depth of the physics with the computational expense that is affordable and in the development of measurement and characterization processes to provide this expanding array of input data required. Steadily increasing computer power has seen model sizes grow from thousands of particles to many millions over the last decade, which steadily increases the range of applications that can be modelled and the complexity of the physics that can be well represented.

The paper shows how better understanding of the flow dynamics leading to improvements in equipment design and operation can potentially lead to large increases in equipment and process efficiency, throughput and/or product quality. Industrial applications can be characterised as large, involving complex particulate behaviour in typically complex geometries. The critical importance of particle shape on the behaviour of granular systems is demonstrated. Shape needs to be adequately represented in order to obtain quantitative predictive accuracy for these systems.

A distinction must be drawn between a dismissal on the one hand, and on the other a repudiation of a contract of employment as a result of a breach of a fundamental term of that contract. When such a repudiation has been accepted by the innocent party then a termination of employment takes place. Such termination does not constitute dismissal (see London v. James Laidlaw & Sons Ltd (1974) IRLR 136 and Gannon v. J. C. Firth (1976) IRLR 415 EAT).

The Equal Pay Act 1970 (which came into operation on 29 December 1975) provides for an “equality clause” to be written into all contracts of employment. S.1(2) (a) of the 1970 Act (which has been amended by the Sex Discrimination Act 1975) provides:

IN recent issues we have had contributionsion the future of Work Study as seen by Council members of the Institute of Industrial Technicians, the Society of Industrial Engineers and the Work Study Society.