Flexible reasoning using sensible agent-based systems: A case study in job flow scheduling

Planning and control systems for highly dynamic and uncertain manufacturing environments require adaptive flexibility and decision-making capabilities. Modern distributed manufacturing systems assess the utility of planning and executing solutions for both system goals (e.g. minimize manufacturing production time for all parts or minimize WIP) and local goals (e.g. expedite part A production schedule or maximize machine X utilization). Sensible Agents have the ability to alter their autonomy levels to choose among a set of decision models in order to handle the differences between local and system goals. In this paper, Sensible Agents are applied to a production planning and control problem in the context of job shop scheduling and decision model theory. Sensible Agents provide for trade-off reasoning mechanisms among system and local utilities that are flexible and responsive to an agent's abilities, situational context and position in the organizational structure of the system.     

CIM implementation for job-shop environments

Abstract

Abstract. The small to medium-sized job-shop manufacturing industry can benefit most from the implementation of computer integrated manufacturing (CIM) technology, to meet the increasing demand for high-quality and economically priced products. The injection mould making industry is a typical representative for this group, where a manufacturer would generally produce moulds which consist of parts that are standard to every mould type or very similar. Thus, manufacturing techniques, such as group technology (GT), and production planning and control (information) management systems could make significant contributions in improving the efficiency of design and production operations.

The objective of the project, presented in this paper, was the development of a GT-based classification and coding (C/C) system for injection mould parts especially for the design and process planning phases, and the development of a production planning and shop-floor control (SFC) information management system.

An extensive investigation was carried out on existing GT-based C/C systems. This investigation, followed by a thorough examination of many injection mould parts for determining geometric similarities, led to the development of part families (classes) required for GT implementation. An OPITZ-type GT system was developed, thereafter, for the C/C of the manufactured parts of the target company.

The production planning and control software that has been developed for the target company utilizes a relational data base management system. It consists of 13 application programs, which provide a tool of organizing information for efficient production planning and SFC. The programs are designed to cover all manufacturing operations of a job from the proposal to the final testing stage. Shop orders and dispatch lists are created using this software for effective and prioritized SFC. Shop status and job status reports are generated based on feedback information received through time card entries.     

Integration of CAD/CAM and production control in sheet metal manufacturing — an application area of operations research

Abstract

This paper describes a process planning system for sheet metal parts. This system has capabilities to deliver process planning data just in time. The change of tools, processes and even machines for manufacturing of the parts is possible at the shop door after design has been finished.

The sequence of the production planning steps carried out can be changed. In this way the system can be adapted to the requirements of different sheet metal manufacturing companies.

More detailed information is given about the methods used for nesting of the workpieces on the sheets to be produced.     

A finite capacity material requirements planning system

In a discrete parts manufacturing environment, material requirement planning (MRP) is carried out without considering the manufacturing resource capacity. As a result, during implementation, adjustments in planned orders may become necessary. This paper presents a finite capacity material requirements planning algorithm (FCMRP) to obtain capacity-based production plans. These plans need no costly adjustments to satisfy the capacity constraints. Performance of the FCMRP system, when studied through a set of test examples, has been found to be superior to the existing MRP system.     

The relative importance of planning and control systems in achieving good delivery performance

Amongst factors such as quick changeovers and workforce flexibility, managers in 533 UK manufacturing plants ranked a responsive planning and control system as the most important facilitator of good delivery performance on products made-to-order or assembled-to-order. The rankings indicate greater importance to companies in the Household and Engineering sectors than in Process and Electronics, where other factors are dominant. These results are combined with data such as customer lead times and item variety, to characterize and explain differences between the plants in these four sectors. Collectively the results indicate considerable differences in the production planning and control tasks. This implies that general statements on the importance of planning and control systems are inadequate. Practitioners need contextual information in order to ascertain when research is applicable to their circumstances.     

Production planning and inventory control in a company manufacturing PC parts: A case study

In this paper, we present a case study on the production planning and inventory system in a company manufacturing personal computer (PC) parts. In the case study, the targets are specified for developing a system for production planning and inventory control. The current state of the company is analysed for clarifying the points necessary to achieve the targets. Also, a system based on the analysis is proposed and its effects are estimated.     

Computational complexity of algorithms for MRP and JIT production planning problems in enterprise resource planning systems

An enterprise resource planning system (ERP) is the information backbone of many manufacturing companies. At the core of ERP is a conventional material requirements planning (MRP) production planning system or a variation of MRP when just-in-time (JIT) principles are used in manufacturing. MRP and JIT both organize production planning into a hierarchy of long-, medium- and short-range problems. In all there are eight different problems. Some are common to MRP and JIT, others are specialized for a particular system. This paper analyses the computational requirements of these problems. This is important for ERP because it plans for large numbers of products (e.g. 50 000 products at 3M Company and 44 000 products at States Industries in Oregon) at large numbers of locations (e.g. 82 locations in 21 countries for Visteon Automotive Systems of Michigan and 19 locations at Boeing). We show that adequate algorithms exist for some problems, but better algorithms are needed for other problems if ERP is to provide useful production plans.     

Shopfloor control practices in three Pacific basin countries: a comparative view of small machine tool industry

The strategic importance of manufacturing decisions to the competitive position of a firm is well known. As the sphere of competition has expanded from regional to national to international, successful manufacturing decisions have become ever more complex. The success of manufacturing strategics ultimately rests on proper tactical implementation at the shopfloor level. In order to explore various operating policies and procedures at a basic level, and to contrast them with some commonly held beliefs, this paper examines and compares the shopfloor practices of companies in the small machines too! industry in selected countries in the Pacific rim, namely; Japan,

China and South Korea. While many popular views on manufacturing practices in these countries are supported by the study, the results challenge other commonly held views.     

Aspects of manufacturing strategy

Abstract

It is becoming increasingly important for manufacturing organizations to articulate clear and coherent manufacturing strategies that support their long term business objectives. In particular, manufacturing strategy should take conscious account of the competitive posture adopted by the organization in each of the product/market segments in which it has decided to participate. This paper discusses the various ways in which a systemic manufacturing strategy can contribute to an organization's competitiveness, and the processes by which such a strategy can be developed. Some important and often neglected issues concerning the development of the individual components of a manufacturing strategy are examined and the problems and issues of strategy implementation are discussed.     

Alternate Routing Strategies in Batch Manufacturing: An Evaluation

Batch manufacturing firms are experiencing significant changes because of technological developments in work center design, such as flexible manufacturing systems (FMS) and planning/control tools like computer-aided process planning (CAPP). These new developments provide production managers with some solutions to a number of complex problems. For example, numerical-controlled (NC) machine center installations are effective in providing quality parts because of tight tolerance specifications built into the equipment. However, these highly efficient centers create bottlenecks that constrain shop throughput, since production planners tend to rely too much on them. To help improve manufacturing planning, we introduce an important element to the batch production scheduling component of CAPP's mission—evaluating possible alternate routes. Production scheduling encompasses job route selection as well as machine center assignment (loading), job releasing, and setting due dates. In this paper, three routing strategies requiring different levels of shop floor information are tested and evaluated using computer simulation. Shop performance is measured by total cost and traditional measures of job flow time, lateness, and tardiness.     

The implications of internationalisation for the management of the vehicle components industry in Britain,Germany, Japan and the U.S.A.

The vehicle components industry, which in recent years has become subject to a more international pattern of competition, provides a good example of how internationalisation forces companies to re-appraise their strategic priorities. The industry's breadth and complexity afford rich international comparisons and suggest conclusions of broader relevance.Thirty British vehicle component manufacturers and thirty from Germany, Japan and the U.S.A. were matched on the basis of six specific components. Field research, entailing discussions with senior executives and factory visits in all four countries, was complemented with desk research analysing the industry more comprehensively.The dramatic decline in company performances, particularly in Britain, reflects over-reliance on higher-level strategies such as diversification, acquisitions, mergers and industrial consolidation, the pursuit of scale economies and the restoration of financial positions through restructuring and retrenchment. Internationalisation calls for competitive strategies that are coherent in the face of powerfully supported international rivals, and generally requires greater market focus. Secondly, basic issues such as manning levels and productivity, quality and flexible manufacturing systems have increased in importance due to radically improved international standards of best practice, established by countries such as Japan.     

Optimal Acquisition of FMS Technology Subject to Technological Progress*

In order to gain competitive advantage, a firm must link its technology choice to its total manufacturing strategy and business unit's goals. A dynamic model is presented to examine the strategic decision concerning the acquisition of flexible manufacturing systems (FMS) technology. A major contribution of this model is its ability to capture the strategic benefits of FMS with respect to economies of scope and technological progress. Decisions such as the timing and size of new technology acquisition and the scrapping of conventional capacity are explored as a firm plans for the upgrading of its facility to meet future dynamic strategic goals. This model may be used to assist with strategic planning because it identifies the critical relationships and trade-offs between various exogenous forces (such as market growth or decay, the cost of acquiring flexible manufacturing systems, and the rate of technological progress) and the decision variables considered.     

MASCOT: An agent-based architecture for dynamic supply chain creation and coordination in the internet economy

The emerging global internet economy will increasingly put a premium on the ability of companies to quickly and accurately evaluate new market opportunities, new product/ subcomponent designs, and other strategic business decisions (e.g. make-or-buy) in coordination with potential supply chain partners. It also requires that companies be able to effectively and efficiently coordinate activities, e.g. production and transportation across supply chains that are dynamically set up in response to constantly changing and increasingly customized market requirements. This paper provides an overview of MASCOT ('multi-agent supply chain cordination tool'), a reconfigurable, multi-level, agent-based planning and scheduling architecture aimed at supporting these functionalities. It reviews key innovative elements of the MASCOT architecture with a special emphasis on its support of realtime mixed-initiative 'what-if' functionalities, enabling endusers at different levels within the architecture to rapidly     

Cost accounting in manufacturing: dawn of a new era

Abstract

Advances in the technology of manufacturing planning, control and operation have made conventional cost accounting practices not only obsolete but dangerous. As a portion of total factory cost, direct labour costs have declined dramatically due to improved quality materials, fewer interruptions, automation and robotics. Overhead costs, conversely, have increased greatly and the fixed components now predominate. Charts of accounts contain many trivial items and lack those now considered very important. This article presents the needed revisions.     

A generic accounting model to support operations management decisions

Information systems are generally unable to generate information about the financial consequences of operations management decisions. This is because the procedures for determining the relevant accounting information for decision support are not formalised in ways that can be implemented in information systems. This paper describes a formalised procedure, which is based on the following theoretical propositions: (i) cost behaviour is described on the basis of a company's contracts for purchasing and selling resources, and (ii) hierarchical relationships between decisions are recognised, because some decisions have to be made earlier than others. Earlier decisions determine the feasible alternatives for later decisions (e.g. through constraints in available production capacity or components), and the plans that supported the earlier decisions serve as instructions for later decisions. The procedure can be implemented in information systems to provide accounting information in case later decisions deviate from these instruc tions (within the limits of the real-world constraints) because new information becomes available.     

Experimental earliness/tardiness production planning with the due window system

In order to use the philosophy of JIT to improve the production planning method of MRP-II, we propose the experimental software system of the earliness/tardiness produc tion planning problem with due window. By means of the approaches and model reported in this paper, the optimal production planning can be achieved. The recommended model extends the problem of due window from the shop scheduling level into the aggregated planning level of mass manufacturing systems. Simulation results have demonstrated that the experimental software is a useful tool for the production management of repetitive manufacturing enterprises.     

Critical success factors of TQM: A select study of Indian organizations

In the context of TQM, it is essential that the organizations identify a few key critical success factors, which should be given special attention for ensuring successful implementation of TQM program. The concept of critical success factors (CSFs) and their use in supporting planning efforts was originated from the approach associated with the development and implementation of management information systems. This paper represents a review of the literature on CSFs and supported by various philosophies of TQM. Such factors are considered as conducive to the success of TQM implementation. Based on an exploratory study of Indian organizations engaged in manufacturing and services, CSFs have been identified.     

Cloud manufacturing system for sheet metal processing

Abstract

Cloud computing is changing the way industries and enterprises run their businesses. Cloud manufacturing is emerging as an approach to transform the traditional manufacturing business model, while helping the manufacturer to align production efficiency with its business strategy, and creating intelligent factory networks that enable collaboration across the whole enterprise. Many production planning and control (PPC) problems are essentially optimisation problems, where the objective is to develop a plan that meets the demand at minimum cost or maximum profit. Because the underlying optimisation problem will vary in the different business and operation phases, it is important to think about optimisation in a dynamic mechanism and in a number of interlinked sub-problems at the same time. Cloud manufacturing has the potential to offer decision support as a service and medium of communication in PPC. To solve these problems and produce collaboration across the supply chain, this paper provides an overview of the state of the art in cloud manufacturing and presents a model of cloud-based production planning and production system for sheet metal processing.     

An approximate summarization method of process data for acquiring knowledge to improve product quality

This paper describes a machine learning approach for a manufacturing database. The method is presented in the Nb-Ti superconducting wire domain. A Nb-Ti superconducting wire is produced by iterating the drawing and heat treatment operations. The purpose is to obtain approximate summarization of process data that describes how a production schedule can be improved for better product quality. The method consists of the following steps: First, define a ranking function for a production schedule. Then, generate 'positive' and 'negative' instances for improving a production schedule by comparing a pair of schedules and their ranking values in the database. Using a machine learning technique, called 'ID3', a 'modification patterns' are obtained that generalize the data for better production quality. The final step is to extract approximate information from the induced patterns, which is both desirable for easier understanding by human experts and necessary to avoid being too much influenced by excessive details or disturbances. Two criteria are proposed, correctness and applicability indices, for this approximation.     

The Tradeoffs of Inclusionary Zoning: What Do We Know and What Do We Need to Know?

Inclusionary zoning (IZ), a controversial planning tool for supplying affordable housing, grew significantly during the 2000s' housing boom in the USA. We review the resultant scholarly literature on IZ. Our key reading is that IZ can include both tradeoffs and practical efforts to address them. There is also a need for additional research. More specifically, we find that IZ programs (i) have many components and vary considerably; (ii) can increase affordable housing production and social integration, but there can be a tradeoff between these goals; and (iii) can have slight adverse market effects, but cost-offsets can help mitigate the outcomes. Finally, we discuss the need for more research, particularly in-depth case studies and make suggestions.