The use of management accounting systems in manufacturing

Many authors have expressed concern about the negative influence of accounting systems on operational decision making. Accounting systems take two forms, management accounting and financial accounting, and can be tightly linked through the use of standard costing common to both. However, the functions of these two forms of accounting are quite different: management accounting is focused on monitoring and analysing the effect of management decisions, financial accounting is focused on short-term, external reporting. The concern is that this linkage is drawing operating decision making into a short-term, narrow focus not supportive of the most effective operations. Since there has been very little work on how standard costing systems are actually used in operations, this work is an exploratory look at practice. This study explores whether the use of standard costing systems is actually contingent on environment, as may be appropriate, and whether its use affects decision making in operations. Results of a survey of 110 manufacturing companies suggest that at least some firms use standard cost systems in environments where they may not be suited and that their use may not be consistent with the manufacturing strategy. Also, results indicate that some operations managers base decisions on external financal reporting rather than internal criteria such as inventory turnover, number of defects, or customer delivery. Further, significant differences in report usage are associated with whether or not a firm uses standard costing systems. Overall, these results suggest that financial accounting and standard costing systems are influencing operations decision making and that far better understanding of this potentially wide-ranging influence is needed.     

Integrated scheduling and tool management in flexible manufacturing systems

A multistage algorithm is proposed that will solve the scheduling problem in a flexible manufacturing system by considering the interrelated subproblems of processing time control, tool allocation and machining conditions optimization. The main objective of the proposed algorithm is to minimize total production cost consisting of tooling, operational and tardiness costs. The proposed integrated approach recognizes an important trade-off in automated manufacturing systems that has been largely unrecognized, and which is believed can be effectively exploited to improve production efficiency and lead to substantial cost reductions.     

Multi-agent systems applications in manufacturing systems and supply chain management: a review paper

This paper offers a review of the development and use of multi-agent modelling techniques and simulations in the context of manufacturing systems and supply chain management (SCM). The objective of the paper is twofold. First, it presents a comprehensive literature review of current multi-agent systems (MAS) research applications in the field of manufacturing systems and SCM. Second, it aims to identify and evaluate some key issues involved in using MAS methods to model and simulate manufacturing systems. A variety of different MAS applications are reviewed in three different classified research areas: production design and development, production planning and control, and SCM. In presenting a detailed taxonomy of MAS applications, the paper describes MAS application domains from five different perspectives. The review suggests the MAS approach represents a feasible framework for designing and analysing real-time manufacturing operations, since the approach is capable of modelling different levels of agent behaviour and dynamical interactions. The paper also highlights a number of key issues which have to be taken into account in attempting to design MAS-based research paradigms for future applications in manufacturing systems.     

The design of business processes within manufacturing systems management

Manufacturing organizations are currently being subjected to increased business, regulatory and legislative pressures that require them to regularly re-engineer themselves. To be able to effectively manage such activities, a manufacturing systems management (MSM) framework is required, which helps to define the necessary activities needed to regulate and optimize a manufacturing system as it progresses through its life cycle. The current merging of automotive manufacturers highlights the need for such a framework. Maximizing the benefits of such mergers requires the effective convergence of the organizations' processes, which is a complex undertaking that requires a structured approach. Through an approach known as Business Process Development (BPD), as used in the case of the design of BMW's new UK engine factory, this paper describes how a MSM framework can be applied in practice to deal with a range of issues related to the analysis, design and implementation of a new manufacturing system.     

Machine cell formation for production management in cellular manufacturing systems

The formation of machine-part families is an important task in the design of cellular manufacturing systems. Manufacturing cell grouping has the effect of reducing material handing cost and work in process. Among the many methods utilized in machine cells formation, the similarity coefficient method is most widely used. Production sequence and product volumes, if incorporated properly in determining the machine cells, can enhance the quality of solutions and reduce the number of intercellular movements. Measures for cell formation based on operations sequence utilizing ordinal production data are few and have many limitations, such as counting the number of the trips for each individual part instead of counting the weights of the batches. A new ordinal production data similarity coefficient based on the sequence of operations and the batch size of the parts is introduced. Furthermore, a new clustering algorithm for machine cell formation is proposed. The new similarity measure showed more sensitivity to the intercellular movements and the clustering algorithm showed better machine grouping.     

Tool management in flexible manufacturing systems with network part program

Recent technological developments have allowed a new concept of a part program to execute the machining operations that remove the software constraints introduced by the numerical control of machining centres. This change allows machines executing a part program to be structured as a net of operations and not linearly as normally happens in shop floors. The main advantage of using the network part program in numerically controlled machines is that it gives the system more flexibility by increasing the number of alternatives that machines can follow during work. In such a way, machines select their path in the network part program taking into account the dynamic state of resources (e.g. spindles, tools, carriers, pallets, etc.). The paper contains a study on the flexibility related to network part program exploitation in numerically controlled machines. Easy-to-calculate indicators are also defined. They estimate the potential flexibility of a network part program related to a particular product. The study has allowed the definition of a new tool management rule to be used in a flexible manufacturing system where the tools are shared dynamically among machines. The numerical results carried out on two different real cases demonstrate the validity of the new concept by quantifying the advantages in terms of throughput increment and machine idle-time reduction.     

Variety and volume dynamic management for value creation in changeable manufacturing systems

In today’s uncertain market and continuously evolving technology, managing manufacturing systems are more complex than ever. This paper studies the dynamics of managing variety and volume to enhance value creation in manufacturers implementing system-level advanced and automated manufacturing technology (AAMT). The demand is composed of heterogeneous customers who make purchasing decisions depending on the variety levels and lead times of the firm’s product offerings. The cost structure adopted calculates profit as the difference between customer value creation rate (VCR) and costs associated with the process of creating this value. Reported results contribute to the variety and volume management literature by offering analytical clarity of factors affecting product platforms and capacity scalability management for systems with AAMT. In addition, insightful answers to the trade-offs between profit maximising market coverage and investments, smoothing demand policies and system stability for this type of environment are presented. Furthermore, the value of market information in deciding the industrial technology investment and also the impact of product life cycle on the same investment is captured.     

Ageing workforce management in manufacturing systems: state of the art and future research agenda

The workforce ageing phenomenon is recently affecting most of the Organisation for Economic Co-operation and Development (OECD) member countries, due to a general ageing of their populations and a higher average retirement age of the workforce. In this paper, the topic of ageing workforce management is addressed from a production research standpoint, with the aim of understanding how older workers can be supported and involved in a manufacturing system. First, the current state of the art related to the ageing workforce in production systems is presented. This is structured according to four main topics: (1) analysis and evaluation of ageing workers’ functional capacities, (2) consideration of ageing workers’ capacities in industrial system modelling and management, (3) analysis and exploitation of ageing workers’ expertise, (4) acknowledgement, analysis, design and integration of supporting technologies. Next, the discussion on the impact of the ageing workforce on manufacturing systems’ performances leads to the comparison of some technological advances that are related to the Industry 4.0 paradigms. Finally, a future research agenda on this topic is proposed, based on the same topics classification proposed for the literature analysis. Five different research areas are derived, suggesting future directions for appropriate research concerning the employ of older workers in production environments.     

A queueing network model for flexible manufacturing systems with tool management

The analytical model in this paper allows the evaluation of the performance of a flexible manufacturing system (FMS) with a tool management system. Design parameters such as the transportation time for tools to machines, as well as the number of transportation vehicles for tools, are explicitly considered. The part and the tool transportation system are modeled as two interacting closed queueing networks. The classical convolution algorithm is used to evaluate the part transportation system and mean value analysis approximation is applied to evaluate the tool transportation system. The resulting set of nonlinear equations allows then to estimate important system parameters such as the throughput of parts, the utilization of the tool transportation vehicles and the service interruptions caused by a tool supply order.     

Theory and practice of manufacturing strategy

This paper first proposes a methodology for manufacturing strategy development based on a critical review of the theory of manufacturing strategy. The methodology captures the essential factors that must be considered, and the steps that must be taken, by a firm attempting to design a viable manufacturing strategy. An exploratory study of the process of formulating and implementing manufacturing strategy practised by three firms is conducted. Their experiences in the manufacturing strategy process are reported and analysed. While the practice of each firm is different, the process of manufacturing strategy formulation seems to be in line with the conceptual models discussed in the literature. Our findings offer some evidence that manufacturing is slowly shedding its image as the ‘missing link’ in corporate strategy. While managers of the studied firms are fully aware of the competitive advantages that manufacturing can provide, they are not totally committed to articulating a manufacturing strategy because of concerns about its successful implementation. It is proposed that further research on manufacturing strategy focus on such implementation issues as the infrastructure, corporate culture, performance measurements, decision-making and managerial styles.     

准时生产方式的学习与实践

从准时化生产方式的基本原理出发，论述了在实际生产中为了适应市场经济多品种，小批量和短交货期的要求，企业构筑柔性生产体制的做法和实施要点。并用实践的效果说明准时生产方式对提高企业综合效益的积极作用。     

Scheduling manufacturing systems for delayed product differentiation in agile manufacturing

Production of customized products to respond to changing markets in a short time and at a low cost for agile manufacturing can be implemented with delayed product differentiation in a manufacturing system. The successful implementation of delayed product differentiation lies in efficient scheduling of the manufacturing system. Scheduling problems in implementing delayed product differentiation in a general flexible manufacturing system are defined, formulated and solved here. The manufacturing system consists of two stages: machining and assembly. At the machining stage, a single machine is used to produce standard component parts for assembly products. These parts are then assembled at the assembly stage by multiple identical assembly stations to form customized products. The products to be produced in the system are characterized by their assembly sequences represented by digraphs. The scheduling problem is to determine the sequence of products to be produced in the system so that the maximum completion time (makespan) is minimized for any given number of assembly stations at the assembly stage. Based on the representation of assembly sequence of the products, three production modes are defined: production of a single product with a simple assembly sequence ; production of a single product with a complex assembly sequence ; and production of N products . According to the three defined production modes, the associated scheduling problems are defined as G s scheduling problems, G c scheduling problems and N-product scheduling problems, respectively. Optimal and heuristic methods for solving the scheduling problems are developed. The computational experiment shows that the heuristics provide good solutions to the scheduling problems.     

Risk-based analysis of manufacturing systems

A manufacturing system considered here consists of a machine that processes parts and an automatic conveyor that transports immediately a finished part to an assembly cell (i.e. a single workstation facility is examined). The system can hold a maximum number of processed parts on the conveyor, which determines its size. Modelling the system as a family of Birth–Death Processes with finite size in equilibrium, indexed by the system utilisation parameter, and depending on the concepts of system information and system entropy (i.e. mean information), we promote a risk-based analysis of manufacturing systems. The current number of processed parts on the conveyor determines the system particular states. The performance measures of a system are: risk (i.e. uncertainty) of the system (represented by system entropy), throughput of the system, utilisation of the machine, utilisation of the conveyor, and information range of the system. They are simultaneously investigated with respect to the system utilisation parameter, in order for an optimal trade-off among them to be established. This analysis is illustrated on the information linear, Erlang, Binomial and Pascal held manufacturing systems. Regarding the managerial insights, a use case of a system target output is considered, comparing the above system types. This approach can also be used for analysis of an assembly line consisting of multiple machines that have different operation times and buffers between them.     

Optimum design of structures by accounting for the manufacturing process

A mathematical statement of the problem of optimum design of structures by accounting for the manufacturing process, called a problem of bioptimum design, is examined. It is shown that solution of this problem reduces to successive solution of the problem of optimum design and optimization of the manufacturing process. To this end, a special minimizing sequence has been constructed. A problem of bioptimum design of hydraulic cylinders is discussed as an example. Four manufacturing process alternatives, including the following finishing operations, are presented: machining, autofretting with internal pressure; shaping on a mandrel; drawing with thinning. As the solution of the problem showed, drawing is the most effective process from the viewpoint of strength of hydraulic cylinders. It provides for a favorable residual stress field and best strengthening of the cylinder material.Translated from Problemy Prochnosti, No. 5, pp. 64–68, May, 1991.     

Ordering scheduling problem in manufacturing systems

The problem of scheduling customer orders in the management of a large multi-product warehouse is addressed under realistic assumptions including rapidly changing data, uncertainties and unforeseen events. Simple flexible solution strategies are sought, in the sense that the scheduling problem should not be solved again from the beginning every time new information becomes available. Among the solution strategies, one is based on a few statistical assumptions about the random variables involved in the process: it exploits a stochastic version of the well-known duality principle for nonlinear programming and yields a number of interesting features.     

Production reliability in flexible manufacturing systems

A typical flexible manufacturing system, Westland Helicopters' sheet metal detail manufacturing complex, has been analysed for reliability. The techniques of fault tree analysis and event tree analysis are presented and their applicability to this study investigated. Event tree analysis has been found to be a more effective method for analysing manufacturing systems. The failure states of the system have been identified from the construction of an event tree which considers random hardware faults that influence production. Failure rate data have been used to quantify the critical production failure states in terms of machine failures. Estimates are made of the system's MTTF and percentage availability using typical MTTR figures. The probability that a selected production route fails to complete the manufacture of a set of parts is also evaluated. A dependency of systems reliability on the production demand has been discovered, and a possible method for modelling and assessing the reliability of systems capable of producing several products is proposed.     

Tooling economics in integrated manufacturing systems

Two alternative objectives when analysing machining rates are to produce components at maximum production rate or at minimum cost. Tn this psiper, a procedure is introduced in which selected jobs, initially programmed in a schedule at maximum production rates, hare their machining rates reviewed in order to reduce costs. An integrated manufacturing system with a job shop work pattern is assumed and in which due date criteria are applied to finished jobs. The cost reduction procedure is designed to operate while maintaining the original schedule performance.     

Influencing factors of synchronization in manufacturing systems

Manufacturing systems exhibit two types of synchronisation phenomena: logistics and physics. Previous research has established synchronisation measures for both types and has shown that they are related to the due date performance. However, there is a lack of knowledge about the factors triggering synchronisation emergence as well as a holistic understanding of synchronisation effects on logistics performance. Thus, this research aims to further explore the relation between synchronisation, its influencing factors and its effect on logistics performance. Based on a profound literature review, we derive first hypotheses on the cause-and-effect-relationships between structural and dynamic properties of a manufacturing system and the emergence of logistics and physics synchronisation as well as logistics performance. By conducting a discrete-event simulation study on diverse manufacturing system types (line, flow shop and job shop production), we are able to test these hypotheses. We conclude that manufacturing network architecture as a structural property as well as processing time variability and system workload as dynamic properties may be exploited for an advanced and synchronisation-oriented manufacturing system design.