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This paper deals with a theoretical programming method for determining conditions of unit cost reductions of dynamic technological processes. The mathematical model has been adopted for use as a dynamic programming procedure. The necessary assumptions needed to use the procedure have been formulated.
The more important part of the work is the optimum principle, enabling the solution of a wider class of problems than is possible with the commonly applied R. Bellman's Principle. In place of the assumptions on critical functional additivity (i.e. the additive nature of costs) due to several trajectory elements (e.g. technological operations), more general moments were introduced. These can be stated as 'the costs of the functional value of the first part of the trajectory causes an increase of the functional value for the entire trajectory, regardless of its second part' and 'each intermediate state required in reaching the optimum of the whole process, is to be reached in an optimal manner'. [ABSTRACT FROM AUTHOR]

This paper is concerned with the organizational problems associated with housing maintenance in the public sector. It is based on a number of studies carried out by the Unit in Government and Local Authority Organizations.
The main problem areas investigated so far include: (a) The fragmentation of responsibility between the different people in housing maintenance systems. (b) The variable obligations of occupants for the initiation of and participation in maintenance work. (c) The nature of the supervisor's role and the job satisfaction of operatives. As a result of these studies, two types of goals have been isolated which can be used to determine the characteristics of maintenance systems: 1. The Demand Goal--The degree of occupant influence on the type of work provided. 2. The Supply Goal--The speed of response of the organization to maintenance demands. It is suggested that the way in which these two goals are reconciled allow four 'ideal types' of system to be identified: (a) An occupant based system. (b) An insurance based system. (c) An owner based system. (d) A work force based system.
The separate interest groups discernable in a system tend to prefer different 'ideal types' and, where any one of these is developed to a pathological extent, the overall satisfaction and standard of maintenance tends to decline. A case study is used to illustrate some of these problems in detail.
Finally, the possibilities of stimulating change in the organizational behaviour of maintenance systems are discussed. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to present a generalized and a special purpose method for the evaluation of throughput time. The general method presented represents a modification of Mason's Rule to a special ease of flow evaluation encountered in production operations. The algorithm presented is for the special model wherein there is a single output and wherein all possible feedbacks are permissible. It is anticipated that the methods presented will aid greatly in the evaluation and understanding of throughput time. The methods should be equally applicable to normal manufacturing operations and to special major project type activities. Clearly the application of the methods is limited only by one's ability to establish the flow graph, the times for the operations and the yields for the various flows. [ABSTRACT FROM AUTHOR]

This paper studies two major problems of development, i.e., making equipment perform satisfactorily after it has been completely assembled: (1) the estimation of actual time spent on development work, and (2) the content and magnitude of the delays occurring during development work. A multi-variate analysis approach is introduced for relating the actual development time with the complexity characteristics of the equipment. On the basis of an extensive survey, significant causes of development delays and their time distribution are established. Although this work concentrates on the development process of special purpose machines used in metal-working industries, it is emphasized that the same methodology can be used for any other types of special purpose machines if the corresponding complexity variables are known. [ABSTRACT FROM AUTHOR]

Reliability has always been one of the most important criteria for designing any type of system. Unfortunately, increase in reliability may produce a design which, once broken down, will take a long time to repair, thus reducing the total time for which the system is available for use. The relatively new concept of availability accounts for this trade-off. This paper investigates the problem of optimal availability allocation in a multi-component system. Two methods are considered, namely dynamic programming and the discrete maximum principle. Numerical examples are presented to illustrate these concepts. [ABSTRACT FROM AUTHOR]

This paper deals with the development of a mathematical model for controlling inventory in a real-life situation. The wide gap between mathematical theory and the building of an actual model is stressed, particularly the necessary, and often difficult, task of adapting known theoretical results to a specific problem. The inventory model chosen is one which approximates optimality and has been modified to accept, as input, demand forecasts from a forecasting model. The inventory-control procedure utilized is of the continuous-review trigger-point order-quantity type, where the trigger point and order quantity 'float', that is, are adjusted periodically depending on the demand forecasts issued. Simulations are performed comparing the proposed inventory and forecasting models with current operating procedures to determine an estimate of the magnitude of the savings possible under the new system. Finally, discussion on how the new system can be implemented is presented. [ABSTRACT FROM AUTHOR]

Traditionally, the human factors evaluation of displays is focused on input aspects (e.g. ratio of line width to height, use of colour, visibility, etc.). Acquisition measures (e.g. reaction-time, reading speed, etc.) have typically been chosen as dependent variables. However, many displays of interest (e.g. those for Command and Control) require the observer not only to acquire information but also to manipulate the displayed data and derive a decision that is judicious as well as timely. This paper will summarize a series of studies in which a decision adequacy metric was applied to the evaluation of displays. It will be shown that several of the relationships previously found (using acquisition variables) are either modified or reversed when we focus on the goodness of display based decisions. A programme of research expanding on these studies will also be described. [ABSTRACT FROM AUTHOR]

This paper presents a review of the exact formulae for control limits for P charts and C charts. Also presented are appropriate graphical methods so that these limits may be easily evaluated. The use of the exact methods, given appropriate tables and/or curves, is no more difficult than the approximate methods which are prevalent in the literature. This note is not intended to criticize the approximate techniques which have been used; rather it is intended to illustrate the use of existing theory whereby the errors of approximation may be eliminated. [ABSTRACT FROM AUTHOR]

Automatic transfer lines are playing an increasingly important role in production. As production rates and capital investment increase, the cost of line stoppages also increases. A line stoppage of an automatic transfer line occurs every time any of the machines stop, unless there is a sufficient buffer stock between each machine in the line. Thus there arises the question of how much buffer stock between each machine is required to optimize line operation in accordance with some criterion such as maximum output or minimum cost.
This paper describes in the first part, one such solution for the case of an automatic bottling plant in a brewery. As a bottling line is a prime example of an automatic transfer line, we believe that the method here described can be applied to all similar problems.
In the second part, an analysis of the theoretical structure of the most common form of automatic transfer line is given, and the practical consequences of this analysis are discussed. [ABSTRACT FROM AUTHOR]

Biomechanical modelling, just as physiological systems modelling, has become quite popular. Biomechanical analysis, and models investigating man's activities while in motion, require records of motion of the entire body and/or its segments. Therefore, it is quite important to devise methods and techniques to record and quantify human movement. This paper will shrew several different techniques, attempted by the author, and their evaluation. Research leading to the development of equations describing human upper extremity movement is presented. Finally, possible applications and new techniques in human movement recording are discussed. [ABSTRACT FROM AUTHOR]

The paper describes work done by the White Fish Authority's Industrial Development Unit to exploit a method of transferring fish at sea between a fleet of trawlers. Both the operations research study and subsequent implementation are described. [ABSTRACT FROM AUTHOR]

This paper describes a project that was performed to maximize profit from the manufacture of a particular type of fork lift truck, with consideration given to manufacturing quantity, range of sizes and sales price. Sales revenue and manufacturing costs were evaluated for each size of truck at different sales levels. The optimal range of sizes was then determined using a dynamic programming approach. The results of the study together with an outline of how the work may be extended in the fixture are discussed. [ABSTRACT FROM AUTHOR]

This paper considers the modelling of an actual batch/flow environment and discusses in detail the basic production system used in this study and its associated sequencing problem. The approach adopted for this problem is outlined and the concept behind the use of a simulation model as a day-to-day tool for production control is discussed. Finally, the limitations of such an approach for a large but fairly stable production unit are presented. [ABSTRACT FROM AUTHOR]

The paper gives a qualitative treatment of a new approach to the synthesis of sequential control systems. Complex sequential control systems can be assembled from a relatively small number of standard sequence packages. These have useful sequential properties in their own right, but the methods for coupling them together to form larger sequential systems are described by the authors. Additional benefit is gained by using the machine actuators alone as memory devices. This removes any possibility of unintentional disturbance of the state of the memory function in the control system. Three examples are chosen to illustrate the design process. [ABSTRACT FROM AUTHOR]

The expansion and contraction of product lines in a company is a decision which affects marketing, production, and distribution staff collectively. This paper establishes a model for a multi-factory company which markets a variety of products in different market sectors with different distribution costs. The problem is to determine how much of each product to manufacture at each factory, whether overtime should be used, how much expenditure to put into selling the product, and how it should be priced. Linear programming has already been used to tackle the product mix problem and this model extends it to include the marketing variables and the possible use of extra capacity. The objective is to make the annual product line plans to maximize total variable profit. The model is illustrated on a simple example. It, is organized into a computer programme for accepting files of typical accounting data and providing a variety of management reports. [ABSTRACT FROM AUTHOR]

The paper describes experimental investigation into the internal broaching process and deals with three related sections. (i) The tendency of a broach to correct misalignments and surface irregularities of the pilot hole. Split workpieces, clamped in a special fixture for machining, enabled measurements and surface traces to be taken after drilling and after broaching. The effect of hole axis inclination, deliberately introduced at the time of drilling was examined. (ii) The tendency of a broach to drift in a transverse direction was studied by the use of composite workpieces built up of similar and dissimilar materials. (iii) Work on section (ii) showed that when broaching a composite workpiece of steel and brass more material was removed from the steel than the brass, i.e. the broach drifted, transversely, towards the steel. To study this effect further, a broaching dynamometer was used to measure tangential and normal forces during the broaching of composite specimens. [ABSTRACT FROM AUTHOR]

Mathematicians have long amused themselves with very difficult problems that are treated as puzzles. One of the more recent of these is the travelling-salesman problem. During last two decades several methods have been developed for solving the travelling-salesman problem, which is akin to many other important problems. The problem of determining a manufacturing schedule, when a number of products are to be manufactured over a production facility, is identical to the travelling-salesman problem. This paper discusses a simple approach to the solution of such production scheduling problems. [ABSTRACT FROM AUTHOR]

This paper describes a general model for planning work flow through a multi-process production system and proposes a new practical scheme of control for scheduling. The features of the model are based on experience of a wide variety of industries and a means is considered for resolving the conflicts between different objectives such as meeting due dates and reducing work in progress. The control system presumes that only the inlet times of the jobs into the production system can actually be decided and managed by a production planner, and not the subsequent internal operation start times, as previous studies have often assumed. A method for optimizing the schedule is developed on the basis of this form of control and it is illustrated on a small example. Finally implementation factors and extensions are discussed. [ABSTRACT FROM AUTHOR]

This paper deals with analysis of man-machine systems by asking for the essential task done by the subsystem 'operator'. By using the method of black-box analysis static and dynamic characteristics of the subsystem can be found.
Different research methods are discussed. Practicable methods should not influence the work situation, therefore a telemetric registration should be preferred.
Examples for analysis of heavy work load, senso-motoric and mental task are given. [ABSTRACT FROM AUTHOR]

The paper indicates the limitations on improved performance arising from physical effort and from information handling and outlines the role of training in improving job performance. Changes in jobs indicate that physical limitations will play less and less part but that other areas of job knowledge will be needed. In particular, the development in job design may call for radically different areas of training than formerly. [ABSTRACT FROM AUTHOR]

Optimization techniques are widely used in many areas and frequently developments of a technique in one area open up opportunity for its use in other areas. This paper presents examples of how the newer techniques have contributed to the improvement in technological processes.
After a brief discussion of optimization, available optimization techniques are classified and the principles of constraint and uncertainty programming outlined.
The application of current techniques to design problems in various production disciplines are then discussed and the Appendix presents some problem solutions. [ABSTRACT FROM AUTHOR]

The paper discusses a deductive strategy for the design of systems in contrast to the more conventional inductive strategy, and indicates the improvements which may be achieved by the use of the Ideals Concept. Practical examples are quoted indicating the effectiveness of the strategy. [ABSTRACT FROM AUTHOR]

This paper examines a special class of behaviour in organizations, namely, social relations between managers of functionally interdependent departments. It is organized around three topics: (1) A discussion of the problem of interdepartmental relations. (2) An overview of theoretical and applied findings on this problem. (3) Some views on the form of future research on this problem. [ABSTRACT FROM AUTHOR]

The purpose of this paper has been to present and exemplify a new and alternate method of return assessment. The method does have computational and mathematical advantage. It is also believed to have analytic advantage in that it is less susceptible to manipulation by base selection and more closely associated with performance measures which are relatively well defined. [ABSTRACT FROM AUTHOR]

A questionnaire was designed to give seven subjective degrees of monotony with other data concerning objective characteristics of the work. The questionnaire was used in plants with similar technology. It could be shown that the criterion of duration of the operation itself is not sufficient for classification of degrees of monotony. It is necessary to add data concerning the structure of operation. Non-technical and organisational factors in production--age, length of time on job, etc.--can affect the degree of monotony, but are not of primary importance. The paper also deals with the subjective aspects of monotony and the opportunity for the employee to change operations. [ABSTRACT FROM AUTHOR]

This paper discusses the use of the geometric programming technique to determine the cutting speed and feed which yield minimum production cost. The method provides for simultaneous determination of the cost optimum values of speed and feed and allows for the incorporation of restrictions on the allowable levels of the machining variables. [ABSTRACT FROM AUTHOR]

In this part of the paper, a method is given for allocating least-cost component tolerances to engineering designs whose functional requirements lead to systems of simultaneous tolerance equations, having one or more component tolerances occurring in more than one tolerance equation. These least-cost tolerances are obtained by minimising the total cost of achieving them, using the method of Lagrange's undetermined multipliers. Methods of solving the resulting non-linear equations in Lagrange's multipliers are given. A notation for the treatment of simultaneous tolerance equations is developed. The procedure is illustrated by examples. [ABSTRACT FROM AUTHOR]

This paper presents a number of results relating to the theory and estimation of improvement curves and to some of the consequences of the improvement phenomenon, such as the importance of labour turnover, the effect on costs of breaking production runs and the need to modify the traditional optimum lot size formula. [ABSTRACT FROM AUTHOR]

The purpose of this paper is two fold: first to provide a method for evaluating projects which have an income pattern describable by a polynomial function of time, and to provide a means for evaluating projects which exhibit a yearly growth or decline in earnings while maintaining the ability to account for the time pattern of earnings, and second to bring forth ah assessment technique which will reflect the possibility of attaining various levels of income for each of the periods of interest. Methods utilized in developing the various models are based on the concept of dynamic return. The future and present worth of a project are calculated for the case in which the earnings follow a pattern of the form given by either Ct[m] or C(1 - t)m. Two types of growth patterns, geometric, in which earnings increase or decline by a fixed percentage each year, and arithmetic, in which earnings increase or decrease by a fixed amount each year, are analyzed. Finally, an income model based on the binomial distribution is developed for evaluating projects which could have two income levels, each having an associated probability. Upper and lower confidence limits for the present and future worths of the project are calculated. Extensions are noted which will permit the inclusion of any of a number of levels of profit for each year of the project. [ABSTRACT FROM AUTHOR]

This paper is concerned with the optimal production planning and inventory control. The first problem is a multiperiod production scheduling problem in which the objective is to minimize the operating cost for a planning period. This cost is composed principally of the sum of the production cost and inventory carrying cost. The second problem considers an inventory system with two decision variables in each planning period. These are the production schedule and work force which are to be determined so as to minimize the operating cost which includes the costs of changing the production rate, of changing the work force and of carrying the inventory. The maximum principle in the discrete form is used to reduce both t he first problem which has N decision variables and the second problem which has 2N decision variables respectively to a series of two decision variables problems. The so-called sequential simplex pattern search technique is used to determine the optimal values of these two decision variables. Numerical examples are given to demonstrate the method. [ABSTRACT FROM AUTHOR]

This paper presents a method of assigning tolerances to components so that (a) assemblies composed of the components meet specified functional requirements and (b) the cost of manufacturing all the components to their respective tolerance is minimised. Methods of obtaining tolerance equations from functional equations are briefly reviewed; the "method of extremes" is explained in detail. A relationship between cost and tolerance is derived, based upon published data.
A method of assigning least-cost tolerances to a single tolerance equation is then developed. [ABSTRACT FROM AUTHOR]

According to standard handbooks and inspection practice, screw thread roll gauges are set by employing special master set plugs. In the present paper, formulae are developed to enable thread wires and gauge blocks to serve the same purpose. The appropriate exact formulae, as well as approximate, easily applicable ones, are derived for symmetrical triangular and trapezoidal threads and the non-symmetric case deduced from the previous results. [ABSTRACT FROM AUTHOR]

Earlier investigation has shown that, from the point of view of flank wear, tool-life can be predicted by the initial cutting temperature. This paper presents a correlation between the drill temperature with cutting speed and feed while drilling cast iron and derives the tool-life equation on the basis of temperature data. The equation obtained agrees well with that obtained by conventional test. [ABSTRACT FROM AUTHOR]

This paper treats work variety as a subjective variable rather than an objective attribute of work. The results of several industrial experiments are outlined in presenting a method for measuring perceived variety in terms of a psycho-physical function. A null finding is reported concerning the relationship between variety and work performance. [ABSTRACT FROM AUTHOR]

This paper reports the use of two techniques which were used to evaluate the important design parameters in a cranking type task. Namely, electromyography served as an indicator of physiological costs for the task, and biomechanical analysis provided quantitative data concerning the mechanical costs for the task. Both these measures were shown to support the importance of handle radius, torque, and working height as critical criteria in design of a cranking task. [ABSTRACT FROM AUTHOR]

In research studies of conveyor-based work, the work-task is often chosen on the basis of experimental convenience. This paper, however, shows that the task itself could be an important parameter in such studies. It is shown that if a work-task is split into two smaller tasks, the relative variability of at least one of the sub-groups must be greater than that of the parent group. This is likely to lead to a decrease in the overall performance of the system. SUMMARY. [ABSTRACT FROM AUTHOR]

It has been assumed in recent research that the distribution of units on conveyors is a stationary Bernoulli distribution. This paper presents a technique which is used to test the validity of this assumption.
The system was simulated using the GPSS III language. A statistical run test is used to test the Bernoulli assumption. From the results of this study, the general assumption that the distribution of units on the conveyor is stationary Bernoulli cannot be supported. SUMMARY. [ABSTRACT FROM AUTHOR]

The paper summarises theoretical and experimental studies of some problems concerning the realisation of broaching of ring thrust faces. It presents descriptions of devices and investigations into the limits of application of this technology such as tool life, the deformation of rings under cutting forces and the stability of rings under clamping forces. The objectives of this project were to increase the productivity rate and continuity of production and to facilitate automation. SUMMARY. [ABSTRACT FROM AUTHOR]

This paper is concerned with the efficiency of the branch-and-bound technique for solving the production scheduling problem. Since the efficiency of this technique depends on a powerful lower bound, five promising bounding procedures are studied and investigated empirically. This investigation is based on the number of nodes explored and the computational time involved. Several computational experiments are conducted and results reported. [ABSTRACT FROM AUTHOR]

This paper develops a method for computing the optimal division of a container into any number (N) of compartments when each compartment contains an item which is subjected to an independent demand over some time period. Each of the N compartments is filled at the beginning of the period and the objective is to minimise total runout cost during the demand period. [ABSTRACT FROM AUTHOR]

This paper examines the problem of optimally locating a main facility with respect to located ancillary facilities when unit transportation costs between the main facility and ancillaries are known. Problems of location both in the planar and spatial states are examined, and an electrical analogue solution is proposed and verified. Solutions to problems with non-linear transportation cost functions are discussed and a worked example is included to illustrate the technique. [ABSTRACT FROM AUTHOR]

This paper develops a method for computing a return ratio which can be of use in investment analysis. Definitions of some of the conventional return on assets calculations are given and the advantages of the proposed method are discussed, especially in regard to comparison of competing investments which involve different time periods.
In the proposed method, an instantaneous return ratio is calculated. As a result, the return ratio becomes a function of time from which an average return is derived.
Finally, comparisons of this method with those usually used are made, and the mathematical consistency of the method is established. [ABSTRACT FROM AUTHOR]

A job shop is defined as a production centre consisting of several machines, each of which may be required for processing jobs of different makeups. The scheduling problem is concerned with determining the sequence in which these jobs should be processed on each machine, and this has led to several studies of alternative loading or priority rules. One rule, which has been found to be effective in reducing the average throughput time of jobs, is thc SI rule, which can be described as follows: of jobs waiting in a queue to be processed on any given machine, select first the one with the shortest imminent processing time.
The study described in this paper involved a simulation of a hypothetical shop with several machines. A number of alternative rules and variations on the SI rule were investigated. One modification or the SI rule called for the creation of two queues, one having a priority over the other and each queue involving an SI discipline. The decision as to which queue a job should belong to is determined by its float, which is defined as the difference between the time available until the prescribed due-date of thc job and the time required for operations still outstanding. The effectiveness of this rule is investigated. [ABSTRACT FROM AUTHOR]

During the last ten years the measurement of production efficiency has attracted increasing interest. In this paper a method for the calculation of an efficiency index has been developed, which takes into consideration changes in product assortment and in production and capital factor inputs. The method was applied, in different parts of Europe, at five subsidiaries belonging to a major Swedish manufacturing company. [ABSTRACT FROM AUTHOR]

This paper extends existing quantitative methods for the economic evaluation of alternative investment proposals to the arena of decision-making within economies characterized by inflationary trends. The models developed may be used in transactions involving one or several countries each having a differing rate of inflation. [ABSTRACT FROM AUTHOR]

The work summarised in this paper has been directed to examine the basic requirements of warehouse layouts. Two simple types of layout have been examined and equations derived for the dimensioning of these, given such information as total volume of stock and number of stock lines. A sketch of the layouts is given.
Ten factors have been considered in arriving at the theoretical layouts and it is shown that different types of layout are affected by different factors, some layouts being independent of factors to which others are sensitive.
Dimensions of a layout can be calculated to minimise handling distance, handling time or space utilisation. Where cost functions are available for these parameters, total cost can also be minimised. The formulae lend themselves readily to computer manipulation, enabling an optimum layout to be determined given only the number of stock lines and volumes stored. [ABSTRACT FROM AUTHOR]

The design of mechanical feeders is very much a matter for experience. This paper illustrates that by experiment and synthesis better understanding of the behaviour of such devices can be achieved. Although the work specifically relates to a particular feeder handling simple cylinders, the exercise is capable of wider interpretation and the techniques evaluated could be applied in a wider sense. [ABSTRACT FROM AUTHOR]

The use of many published indices as aids for decision-making is demonstrated to be largely unsubstantiated in theory and of only limited value in practice. This paper attempts to define the useful areas of applications of indices in the decision-making process. A technique is postulated whereby indices are used as a measure of the state of the system, and a decision-rule, which is compatible with some real objective, is determined. In this way the value of an index can prescribe what action is necessary rather than just indicate that some action is necessary. The arguments are developed in the context of the maintenance function, but the general conclusions can be applied equally well to other indices irrespective of their field of application. [ABSTRACT FROM AUTHOR]

The calculation of economic lot sizes with more than one constraint on the system is a recognized problem in inventory control theory. This paper presents a simplex like solution procedure. The algorithm as presented can be readily adapted to other constraints which may arise in a specific application. The essential conditions for application are that the non-linear constraints and/or objective function be differentiable, convex functions. [ABSTRACT FROM AUTHOR]

This paper is concerned with the evaluation of tool stresses in the orthogonal cutting process. Theory and elasticity methods are applied to determine these stresses within the elastic region. In this analysis the tool is considered as a wedge with the normal and frictional loading on the rake face. For general conditions of loading it has been found that the equivalent stresses are of the order of a hundred thousand pounds per square inch. It has also been found that tine equivalent stresses decrease with positive rake and increase with negative rake. [ABSTRACT FROM AUTHOR]