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Modern production concepts can be considered as an essential field of economics nowadays. They help to give valuable insights and thus provide important competitive advantages. There is a broad variety of new approaches to Production Planning and Control (PPC), Just-in-Time (JIT), Flexible Manufacturing Systems (FMS), Flexible Automation (FA), Automated Guided Vehicle Systems (AGVS), Total Quality Control (TQC), and Computer Integrated Manufacturing (CIM), all of which are indispensable cornerstones in this context. This book presents in a condensed and easy-to-comprehend form the different contributions of a group of internationally recommended scientists. The varied approaches to modern production concepts are not only based on theoretical foundations but also go one step further in that they present the implementation of these concepts and methods in detail. This close link with practical aspects will help to illuminate the theoretical material for researchers and students in universities. The book will be of major importance for practitioners involved in solving everyday industrial problems. The interdisciplinary nature of these contributions will help to create a new and valuable perspective on the field of production concepts.



Production Planning and Control


Constitutive Aspects

A Theoretical Basis for the Rational Formation of Production Planning and Control (PPC) Systems

The analytic importance of the economic theory for the area of production management can be shown by many references. From the methodical-theoretical point of view, however, production management and production theory have experienced the most fruitful prospects for expansion through the activity analysis developed by KOOPMANS (1951) which has gradually been introduced into the considerations of business management (WITTMANN 1968, FANDEL 1987, DYCKHOFF 1988). The efficiency of the activity analysis as an examination instrument and modelling concept is founded on many circumstances and advantages.

Günter Fandel

Comparison of Two Production Logistics Concepts

Logistical problems arise when departments confine themselves to considering the material-flows only in their own functional areas (purchasing, production and marketing) and ignore the effects of their decisions upon the enterprise as a whole (figure 1).

Günther Zäpfel

Multi-Period Production Planning and Managerial Accounting

Profits and costs are important objectives in production planning. Therefore many production models involve cost parameters. Their values must be calculated within the system of cost accounting.

Hans-Ulrich Küpper

Flexibility of Production Control Systems

Recently, manufacturing flexibility becomes a topic to be researched all over the world. The production systems with flexibility, such as FMS or CIM, have been developed, and a lot of studies with respect to the flexible systems have been researched. In addition, the flexibility of production systems itself has been also researched.

Katsuhiko Takahashi, Shusaku Hiraki, Michio Soshiroda

A Quantitative Measure for Flexibility

During the last decade flexibility has become a key notion of modern life and sciences. Especially for management science dealing with the dynamics of systems, flexibility turns out to be of particular importance. Expressions like flexible manufacturing, flexible workforce, and flexible market behaviour indicate its popularity.

Christoph Schneeweiss, Martin Kühn

Applications of Operations Research in Hierarchical Production Planning

Production is one of the traditional fields of application of operations research. The following examples may indicate that decision models describing problems of production planning and control and deriving optimal solutions or good approximations have been developed quite early.

Klaus-Peter Kistner, Marion Steven

Aspects and Elements of Production Planning and Control (PPC)-Systems

Hierarchical Approach to Production Planning and Scheduling: The Case of a Mosaic Tile Plant

This paper describes a production planning and scheduling model developed for a large mosaic tile plant. The company has over 20 overseas customers. In the ordering process, the company gives a monthly production quota for each customer. The order in which each customer uses his quota is called “fixed date order” because the customer can determine the delivery date by himself. The order that does not use the quota system is called “tentative order” because the customer can only determine the delivery month. The delivery date of this order type will still have to be confirmed by the company.

Mario Tabucanon, Anukul Kongrit

Operational Control of Automated PCB Assembly Lines

The rapidly changing market demand characteristics, the increased pace of technological developments and fiercer competition has forced almost any industrial company to fundamentally rethink its manufacturing strategy (cf. Hayes and Wheelwright[1984], Skinner[1985]). In gaining competitive advantage quality, flexibility and speed of innovation have become important performance measures, next to being efficient (Bolwijn et al.[1986], Buzacott[1982], Solberg et al.[1985], Bullinger et al.[1986]). These changes have affected industrial organisations at almost every level: in logistics (MRP, DRP), marketing and product development (DFA, DFM) as well as in operations on the shopfloor itself, by the introduction of CNC machining centres and, finally, of Flexible Manufacturing Systems (FMS) and Flexible Assembly Systems (FAS).

Henk Zijm

A Framework for Developing Production Control Systems: A Case in Coffee Roasting/Distributing

Production situations are unique. The way to control production has to be matched to its characteristics. The term production control concept stands for the heart of such a way of control. It is something like a proper view of the production situation; proper in the sense that on one hand the characteristics of the situation, as far as relevant for production control, are sufficiently taken into account, and on the other hand that it is suitable as a basis for developing rules, procedures, performance measures and information systems. A production control concept is the way production control is stratified. To develop a production control concept requires care. Meal [1984] in his plea for a hierarchical approach of production planning and control stressed already the difficulty of the idiosyncracy of production situations. A too standard approach has to be avoided indeed. But by stressing the uniqueness of the situation too much it may get difficult to apply available general production control principles.

Jacob Wijngaard, John Miltenburg

The Impact of Forecast Errors in Multistage Production Systems

In their pioneering work on aggregate production planning, Holt, Modigliani, and Simon (1955) and Bowman (1963) demonstrated that forecast errors can significantly increase manufacturing costs. Without having a perfect forecast, total costs increased by 10 percent. More recent work on the cost of forecast errors goes beyond the simplifying assumptions of a single product and single homogeneous work force. Forecast errors are being studied in the more realistic multistage manufacturing setting where parent-component relationships exist and there are capacitated work stations. However, the results to date imply that the impact of forecast errors depends on the manufacturing environment. The purpose of this paper is to find out more about these contingencies in realistic manufacturing settings, thereby adding to the growing literature base on how forecast errors affect manufacturing performance.

Larry Ritzman, Barry King

Integrated Manufacturing Planning

This paper will develop the formal structure of hierarchical manufacturing planning and present an integrated example. Management control of the planning process can be achieved by a formal development of the production plan and the master production schedule (MPS). A production plan sets the annual commodity plan for capacity, inventory and workforce units. The capacity and inventory data are passed to the capacity-constrained master production schedule which determines the lot sizing and timing of family/product production. The MPS data will “drive” the detailed material plan.

Lawrence Vitt

Alternatives for MRP

Material coördination is the activity, which coördinates the order release decisions for successive stages in a multi-echelon production/inventory system. A well-known concept for material coördination is MRP I. See Orlicky (1975). Unfortunately, MRP I is not a very suitable concept in a stochastic environment.

Karel V. Donselaar

A Widely Acclaimed Method of Load-Oriented Job Release and its Conceptual Deficiencies

In the last decade, a heuristic method of load-oriented job release, commonly referred to as “Belastungsorientierte Auftragsfreigabe” (BORA), has been developed (cf. e.g. (4); (53)) and very successfully promoted throughout industry. Several standalone software packages with BORA-implementations appeared in the market and BORA-modules have been added to widely used MRP II-systems like COPICS, RM-PPS, PSK2000 and INTEPS (cf. (14), p.24; (59), p. 259). The main goals pursued in connection with BORA are: Reduction of lead time and lead time variability by reducing work-in-processReduction of inventory to reduce holding costReduction of lot sizes to smooth production flow, to prevent unpredictable machine idleness, and to avoid changing bottlenecks in the manufacturing system.

Gerhard Knolmayer

Just-in-Time (JIT)

JIT in a Low Volume, Hi-Tech Production Environment

The implementation of JIT in medical instrument production presents a significant challenge because the devices manufactured are used in life support and critical care environments. Thus quality and reliability cannot be compromised by any change in manufacturing strategy. An additional challenge is brought about because the volume of the hi-tech, hi-cost instruments is relatively low and the cycle time per operator is relatively long, averaging approximately 30 minutes.

John Carlson, William Osgood, Nick Konovalov

A Study of JIT Application under Stochastic Demand and Supply Arrival

A simulation and analysis of variance study was conducted of a production line system operating in a near Just-In-Time (JIT) mode. The objective was to investigate the effect of four system parameters on the production line idle time and the carrying time of inventory. The system consisted of a production line producing one unit of product each production cycle to a JIT demand, each cycle was defined as one unit of time. The demand arrived stochastically during each cycle. The system was supplied by a supplier delivering materials with a stochastic arrival time of up to two cycles. The four system parameters were (1) operating inventory order quantity, representing a policy of ordering which permitted supply arrival for more than one cycle of production requirement, (2) stochastic demand arrival of up to one cycle, (3) safety stock of up to 3 units (Kanbans) of production, and (4) stochastic arrival of supply of up to three cycles.

Mohammad Jalali, Rafael Moras, Richard Dudek

A Comprehensive Study of Quality Management Practices in JIT and Non-JIT Firms

In recent years, there have been numerous books and articles on the subject of JIT production system. These works cover many aspects of JIT such as its philosophy, definition, benefits, and requirement for successful implementation. These publications vary from descriptive, to survey, to simulation, and to actual case studies. The concept of just-in-time (JIT) production system requires continuous improvement via waste elimination throughout the organization. The concept of continuous quality improvement in a JIT environment covers all aspects of production from raw materials to finished goods and after sales services. The quality factor and its importance as an essential element for the success of JIT manufacturing system has been discussed in several books and numerous published articles. However, most studies related to JIT system treat the concept of quality lightly and do not examine it in great detail. This paper provides a detailed examination of the role of quality in the JIT environment by identifying a set of characteristics which are necessary to implement a continuous quality improvement system in an organization. This quality system should, in turn, pave the way for the successful implementation of the JIT system.

Maling Ebrahimpour

Trade-off between Production and Inventory Costs with Respect to a Given Demand Situation

Modern concepts in production management argue that it would be possibly preferable to instal a production rate which is fully synchronized with those rates of other production stages in the same firm or other firms. Thus, between the supplier and the customer of a finished or semi-finished product no inventory costs have to be taken into account, if the coordination will be perfect and JIT(Just-In-Time)-production takes place. Within a firm the synchronization may be a matter of planning and organization, and the kanban-principle is one possible result, though inventory is not really zero, but there exists always a buffer stock. As soon as two different firms are concerned, there are also different planning processes, and the advantage of the customer may become simultaneously the disadvantage of the supplier.

Joachim Reese

Inventory Problems

Combined Optimization of Safety Stocks and Processing Lead Times in Multi-Stage Production Systems

Production planning in a multi-stage environment usually is performed with MRP systems using inputs in form of known and constant processing lead times, yields, and product demands. In practical problems one often is faced with the problem of appropriate integration of demand uncertainty and lead time variability in a MRP planning process.

Karl Inderfurth

On the Commonality Problem in Multi-Stage Inventory Control Systems

This paper addresses a so-called assemble-to-order environment. There are a number of end items each of which requires an assembly of several components. Some of the components are unique to specific end items while others are common to two or more final products. Components must, due to their long leadtimes, be ordered prior to knowing the end item demand levels, but final assemblies can be quickly completed after knowing the demands.

Henrik Jönsson, Edward Silver

Effect of the Standardization of the Hierarchy Parts Structure of a Product (SHPSP) on Production Ordering and Inventory Levels

In recent years, changes in users’ values have diversified and complicated users1 needs. This diversity of needs has made the market more segmented and has led to an increase in the number of items produced by each manufacturer as well as to increased fluctuations in product demand. Companies must continue to improve product quality and reduce lead times and costs to succeed in severe competition for sales.

Kazuyoshi Ishii, Toshihiko Suminokura

A Stochastic Model for In-Process Inventory

The problems of In-process Inventory can be successfully formulated in terms of the Inventory levels which allow the maximum production or the lowest per unit cost. In this paper a reliability - theoretic approach to solve In-process Inventory problem in a Concrete Brick Manufacturing Plant is proposed. The model deals with stock out probability of the bunker of rated capacity assuming that the depletions of the stock from the bunker is linear with respect to the failure rate of the bunker.

Sankaran Ramani

An Inventory Model with Lateral Transshipments

In practice it is quite common to have several parallel regional warehouses when distributing products over a large geographical area. Each warehouse is then providing service to a certain local market. The regional warehouses normally replenish their stocks from a common supplier. In the event of a stockout at a warehouse it may be advantageous, however, to replenish from a nearby parallel warehouse instead of from the common supplier. Such lateral transshipments may improve the service-performance of the total system considerably. Therefore, many companies use lateral transshipments systematically. It is, in general, quite difficult, though, to model lateral transshipments in inventory systems, and most inventory models assume that such transshipments are not allowed.

Sven Axsäter

Scheduling Problems

A Flexible Decision Support Framework for Production Scheduling

Momentarily decision support systems (DSSs) can roughly be categorized in two groups. DSSs in the first group are designed for a single decision situation and are mostly hard to adapt for other decision situations. DSSs in the second group can be considered as DSS generators. A broad range of decision situations can be defined by these systems but they are difficult to manage. Often these DSS generators require extensive programming experience to be able to construct a DSS for a particular decision situation. Furthermore, variations in the decision situation usually imply that a completely new DSS has to be generated. Neither of the two groups possess adequate flexibility. They either cannot be extended or are hard to adapt for a particular decision situation.

Auke Woerlee

The Leitstand — A New Tool for Decentral Production Control

Current applications for production planning and control (PPC) lack adequate support for shop-floor control functionalities. In an environment of changing markets and fierce competition this becomes increasingly disturbant as demands for short delivery times, low batch sizes in production down to a batch size of one, holding of promised delivery dates and flexibility in production increase significantly.

August-Wilhelm Scheer, Alexander Hars

Scheduling with Alternative Process Plans

Automated manufacturing systems may require a considerable capital investment. The key to success in implementation of automated manufacturing systems is effective utilization of manufacturing resources through application of efficient scheduling algorithms.

Jaekyoung Ahn, Andrew Kusiak

Scheduling and Resource Allocation Problems in Some Flow Type Manufacturing Processes

Many manufacturing processes characterize by a flow of works (jobs) through successive machines (processors, devices) in a given technological order. The classical multi-machine flow-shop problems have traditionally been considered in many papers (e.g. in [11]) under the assumption that work processing times are-constant parameters, However, in many manufacturing processes work processing times may vary over the ranges of durations bounded by the maximum (normal) and minimum (crash) value of duration. In other words in such situations a scheduler (an algorithm) may have at its disposal certain continuously - divisible limited resources, such as financial outlay, energy, gas, fuel, catalyzer, raw materials, power, which may be applied to reduce effectively the processing times of individual works. Such problems require a more general approach to scheduling, one that determines not only the order in which works should be processed, but also the distribution of limited resources to individual works or to machines on which they are processed.

Adam Janiak

Intelligent Control of Flexible Manufacturing Systems

Computer Integrated Manufacturing (CIM) has existed, in concept, for several years. While it is still generally believed that CIM can have a major positive impact on productivity, it is far from commonplace in today’s factories. The high costs of software development, maintenance, and integration are among the most prominent reasons for our slow evolution to CIM. More specifically, many computer packages have been developed to address specific manufacturing tasks like scheduling or process planning. Unfortunately, these software systems fail to provide the “hooks” needed for total Manufacturing System integration. This happens because these programs are: 1) developed by different vendors, on different hardware platforms, 2) not meant to be integrated with programs from other vendors, and 3) not part of a overall CIM architecture.

Sanjay Joshi, Richard Wysk

Event Graphs for Modeling and Evaluating Modern Production Systems

In this paper, the performance problem of job-shop and assembly systems with deterministic manufacturing times under cyclic production process is addressed. In both types of systems, the ratios of the various product types to manufacture are given. The set of the ratios is known as the product mix. The control of a production system in order to meet the given ratios is obtained by associating a machine sequence to each machine. Such a sequence defines the sequencing of the product types (or the sequencing of the components of the products types, in the case of an assembly system) on a machine. The proportion of a product type (or a component) in a machine sequence tally with the related ratio. If one of the machine sequences does not reflect the corresponding ratio, it has been proved in [1] that the system blocks after a finite period of time.

George Harhalakis, Said Laftit, Jean-Marie Proth

Scheduling a Work Conserving Queue with Deadlines: Minimizing the Cost of Getting the Work Done on Time

The literature on job-shop scheduling with deadlines has been shaped by this paradigm: Paradigm 1 (1)Jobs are processed over a fixed number of hours per day, and overtime is unavailable;(2)Some jobs will inevitably be tardy; and(3)The performance of a scheduling system should be measured on the basis of job tardiness (or earliness).

Randolph Hall

Analytical and Simulation Techniques Used to Gain Insight into Multi Product Machine Shop Control

Traditional classical control theory has been well established in the design techniques developed in hardware applications such as machine tool drivers, aircraft autoland systems [1] etc. Equivalent modern control theory which yields similar results has been applied to manufacturing systems [2]. In both cases, we can therefore apply the principles learnt in “hard” systems to “soft” and organisational systems [3].

Preetinder Cheema, Denis Towill

Production as a Competitive Weapon


General Concepts

World Class Manufacturing in the 1990s: Integrating JIT, TQC, FA, and TPM with Worker Participation

In the 1980s, we have witnessed revolutionary changes in the concepts and practices of the management of manufacturing systems. Numerous unconventional production management techniques, mostly tributed to such well respected Japanese production management pioneers as Taiichi Ohno and Shigeo Shingo, have been not only taught but also applied in many American firms. Technical terms originated in Japan such as JIT (Just-in-Time), Kanban, SMED (Single-Minute Exchange of Die), and Poka-yoke have already become terms frequently used in the United States by practitioners in industries and faculty and students in academic institutes as well. There is no doubt that Japanese production management experts and their innovative concepts and techniques have greatly facilitated productivity improvements in many American plants. However, the most important lesson we can learn from Japan, in our opinion, is their attitude of “never satisfying with the status quo”. We believe that “continuous improvement” is the real key to gain competitiveness in the 1990s. American companies should not simply dwell on what they have learned from their Japanese competitors and be content with the productivity improvements they have managed to gain so far. Facing an increasingly dynamic international markets, American firms cannot afford to overlook any potential means for “continuous improvement” [21].

Philip Huang

Time-Based Competition: Speeding New Product Development

The emergence in an industry of a firm with a significant time advantage in delivering a product to market fundamentally changes the nature of competition from a cost basis to response time. How to compress time in all phases of the product delivery cycle and turn it into a competitive weapon is the essence of time-based competition.

Joseph Blackburn

Concurrent Life-Cycle Engineering for the Optimization of Products, Systems, and Structures

Production is not an end in itself. It is a means for delivering superior product attributes to meet customer expectations. Superior product attributes are quality “effects” resulting from design “causes”. This paper addresses concurrent life-cycle engineering methodology for bringing quality products, systems, and structures into being.

Wolter Fabrycky

Designing New Production Systems

Strategic Formation of Manufacturing Cells

Achieving the status of a world-class manufacturer requires a direct linkage between the needs of the marketplace and the manufacturing process needed to produce the products. Companies seek market niches by emphasizing certain characteristics of their products or manufacturing systems such as low cost, high quality, fast delivery speed, or volume flexibility. We call these characteristics competitive priorities. However, many firms find themselves in the position of producing products with differing subsets of these competitive priorities on the same manufacturing processes. This can happen when new products are introduced or the firm enters new markets over time. This often causes difficulties for managers because of the conflicting manufacturing tasks that are implied [10]. For example, achieving low costs might require large batch runs or dedicated equipment utilizing low-skilled workers, while providing product flexibility might require low-volume runs on general purpose machinery utilizing skilled workers. In addition to differences in resource needs, there may be differences in infrastructure needs such as reward/incentive systems, inventory control systems, or vendor contracts [11].

Chwen Sheu, Lee Krajewski

Scale, Scope or Division of Labour: Coping with Volume, Variety and Variability in Manufacturing

We are all familiar with Adam Smith’s description in “The Wealth of Nations” of the organization of the manufacture of pins based on the principle of the division of labour. Ever since, conventional wisdom has held up the desirability of using this principle of dividing up the work required in manufacture into a number of steps performed in series. It is only when demand is insufficient to keep more than one person busy that division of labour would not be used. Yet, when one looks at current developments in manufacturing, it is surprising the extent to which there is a general trend away from the organization of manufacture around simple series flow with considerable division of labour. Nor does there seem to be much of a place for the individual craftsman, capable of making a very wide variety of products, with whom Adam Smith contrasted the, to him new, form of organization around coordinated series flow. Rather there seems to be several, perhaps converging, trends in manufacturing organization. One is the development of cooperatives of crafts people who share accounting and marketing services and who agree amongst themselves about how work should be shared. This form of organization seems to be most developed in Northern Italy but it can be found wherever adequate communication facilities for both information and goods exist and perhaps also where relatively inexpensive computer controlled manufacturing equipment can be used. Another trend evident in the Eurpean and North American automobile industry is the abandonment of the use of the traditional moving belt assembly line, with its rigid work pacing and tight linking of work tasks, for those manufacturing operations that still require people to perform the production tasks (see Buzacott 1990).

John Buzacott

Performance Evaluation of Flexible Manufacturing Systems with Starving

Real-life flexible manufacturing systems (FMS) often suffer to a considerable extent under utilization losses which are due to limited local and/or central buffer space and the limited velocity of the material handling system (MHS). In particular two forms of performance deterioration are distinguished: blocking and starving. A workstation is blocked if it cannot dispose of a finished piece because there is no buffer space — neither local nor in the central buffer. Blocking has been studied by several researchers (Akyildiz 1988a, 1988b, Altiok and Perros 1986, Suri and Diehl 1986, Gershwin and Schick 1983, Perros 1984, Yao and Buzacott 1985, 1986). In an earlier paper, the authors have made a proposal to estimate the influence of blocking on the performance of an FMS (Tempelmeier, Kuhn and Tetzlaff 1989) using standard closed queueing network algorithms. According to our experience, in industrial practice blocking often does not seem to be a severe problem during the configuration phase of an FMS, because in many cases it is possible to allow for enough central buffer space at moderate costs to prevent blocking. However even if the central buffer space is large enough, the limited velocity of the material handling system (MHS) in combination with limited local buffer space may lead to a form of reduction of machine utilization that is known as starving.

Horst Tempelmeier, Heinrich Kuhn, Ulrich Tetzlaff

Non Delay — Revisited

A Flexible Manufacturing System (FMS) is capable of simultaneous production of a medium sized volume of a variety of products. This production system is an integrated Computer Controlled system composed of CNC machine tools / centers and automated devices for workpiece manipulation and control.

Janez Dekleva

A Heuristic Approach to FMS Process Planning

A flexible manufacturing system (FMS) is an integrated system of numerically-controlled machine tools and an automated material handling system under the supervision and control of an on-line host computer (Draper, 1984). An FMS can simultaneously process a number of different part-types of medium batch sizes in a random manner. FMS is fast becoming an appropriate production method for mid-volume batch manufacturing. This is due to the fact that FMS has dual advantages over conventional production methods, especially the job shop production system. The advantages are, namely, higher production efficiency and greater flexibility with regard to part-type variety and production.

Edwin Cheng

A Review of Research on AGVS Vehicle Management

There are various interacting elements that affect the performance of an AGVS. Because the effectiveness of an AGVS is very sensitive to operational design parameters, several researchers have addressed issues related to network layout [Gaskins and Tanchoco 1987, Gaskins et al. 1989, Kaspi and Tanchoco 1989, Bozer and Srinivasan 1989], location of pick-up/delivery stations [Usher et al. 1988, Rabeneck et al. 1989], fleet sizing [Egbelu 1987, Leung et al. 1987, Tanchoco et al. 1987], unit load sizing [Egbelu 1987, Steudel and Moon 1987], and vehicle management. This paper outlines the vehicle management control strategies discussed in previous studies on AGVS.

C. G. Co, Jose Tanchoco

Flexible Assembly and Shortest Queue Problems

For the design of flexible assembly systems an iterative approach seems advisable. Such an approach would require the evaluation of several alternative designs. Therefore it is necessary that individual designs can be evaluated very efficiently. In this paper it is argued that extended shortest queue models can play an important role in designing flexible assembly systems. Consequently, it would be essential to have efficient methods to evaluate shortest queue models. The paper presents a new approach for shortest queue models and shows how this approach can be used for several variants. The approach uses mixtures of product forms as approximative solutions for the equilibrium distribution of the Markov chain. Although no rigorous proofs are presented in this paper, it is indicated that the exact solution can be approximated deliberately good in this way with the particular property that the approach also generates upper and lower bounds.

Ivo Adan, Jaap Wessels, Henk Zijm

A Quantitative Model for the Analysis of Distribution Network Scenario‘s

Multi-echelon distribution networks exist to support customer service and to provide transportation economics. For an overview of the managerial problems and possible solutions see for example Tersine [1] and Vollmann, Berry and Whybark [2]. For an introduction to the mathematical analysis of multi-echelon network models and solution techniques we refer to Schwarz [3] and Axsäter, Schneeweiss and Silver [4] and Silver and Peterson [5]. In this paper we discuss managerial and inventory control problems starting from the description of a real-life problem.

Jan v. Doremalen, Hein Fleuren

Computer Integrated Manufacturing (CIM)

Systematic Development and Implementation of CIM Systems

Until a few years ago only specialists used to know the term and the meaning of ‘Computer Integrated Manufacturing’ (CIM), now it is known widely. This is because further development in this area has wide-ranging effects not only on the manufacturing industry, but also on the future sociological and political conditions of the human society in general. Therefore the industrial enterprises all over the world realize that it is of primary importance for them to implement CIM. However, as this involves extraordinarily extensive and complex efforts, implementing CIM is a big challenge for each enterprise.

Günter Groditzki

New Approaches to CIM Specification

In the past there have been many examples of both computer systems and manufacturing systems which have delivered less than they promised. Frequently, the fault is due to inadequate specification of the system at the outset (Carrie, 1990). Too often aspects of the system, which it is known will need to be addressed at some time have been left over until later. At the commissioning stage it may be found that they are critical to the specification and efficient operation of the system. The result is that either the efficiency of the system is compromised throughout its life, or can only be achieved through additional expenditure which was not budgeted for at the start of the project.

Allan Carrie

New Looks on CIMS Modelling

Computerised Production Management Systems (PMS) bear the form of Decision - Support Systems (DSS). For the DSS-design, modelling is essential. It has two major roles: (a) It must help the understanding (and the structuring) of the PMS - problems, and (b) It must facilitate the DSS-design tasks. The INTEGRATION aspect in the framework of Computer Integrated Manufacturing Systems (CIMS) involves a much higher degree of complexity (Hordeski 1988, Browne et al 1988). It calls for new approaches to modelling problems. In this paper, we present the basis of an INtegrated COnceptual REference MOdel (INCOREMO). It is: (a)integrated, because it must cover all types of system structures and activities;(b)conceptual, because it must be generic to cover large classes of problems;(c)reference, because it must show typical ways to establish models of specific applications;(d)model, in the sense of organising and structuring the reality.

Lucas Pun

Design of Interfactory Computer Network Interconnection

During the last decade, the expansion of local area computer networks has been impressive, regarding industrial applications as well as office implementation. This developping trades do not seem to stop in the near future [1]. On the other hand, the public data and telephone networks are continuously changing from amalog to digiatal techniques, reinforcing their reliability, ensuring the transimission of any kind of information (voice, data, image) over large distances with very low transmission error probabilities. New kinds of telecommunications networks have been appeared, for example, Metropolitan Area Networks (MANs), Cable Television Networks, Videotex Networks et.c. As a result, the necessity to interconnect all these telecommunications facilities into one integrated network has become apparent. This enormous ability of information transfer angments the productivity and the automation of any job giving to people the possibility to be supervisors rather and not hardworkers.

Niovi-Fotini Pavlidou, Byron Papathanassiu


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