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The aim of this research is to discuss the benefits of U-shaped layout for production cell operating in variable takt time. Different experiments were conducted using benchmarks to highlight the performance gap between a linear cell and a U-Cell.

The implementation of the production cell, either in a U-shaped or in a straight line layout, is optimized through linear programming based on the number of operators. The two corresponding programs, in Mosel language, use the same approach to not introduce bias in the comparison of results. The study used the authors’ own datasets and other well-known academic benchmarks.

A comparison was conducted between the obtained takt times, with equivalent operating conditions, in both U-Cell and linear cell. A significant increase of the production rate was observed. This increase has often exceeded 10 per cent, reaching 32 per cent. All the experiments show that, with the same number of operators, a cell in a U-shaped layout is always at least as efficient, in terms of attainable production rates, than an equivalent linear cell. Ninety-six per cent of the studied cases give an improvement of production rate. Moreover, the dispersion of the U-Cell results is weaker, which suggests that the U-shaped layout gives better performances in more robust manner.

Results were obtained through a study of various academic benchmarks. The results must be validated on industrial situations.

This paper will be very useful for researchers and practitioners to understand lean implementations and their derived benefits. This paper will allow them to evaluate and analyze the expected benefits of the implementation of the production cell in the U-shaped layout (operating in variable takt time).

U-Cells constitute an appropriate solution for a layout of any kind of production cells with a variable structure (variability of the number of operators, of the organization of the cell, of the takt time […]). When facing a significant variation in the demand, the response consists of adjusting the number of operators assigned to the cell. This study jointly addresses the problem of the U-shaped layout and the operation in variable takt time.

Preface The functions of business divide into several areas and the general focus of this book is on one of the most important although least understood of these—DISTRIBUTION. The particular focus is on reviewing current practice in distribution costing and on attempting to push the frontiers back a little by suggesting some new approaches to overcome previously defined shortcomings.

In the face of growing demand for care and tightening resource constraints, hospitals need to ensure access to care that is affordable and effective. Yet, the multiplicity of objectives is a key challenge in this industry. An understanding of the interrelationships (tradeoffs) between the multiple outcome objectives of care (throughput, experiential and financial performance) and returns to operational inputs (diversification of care) is fundamental to improving access to care that is effective and affordable. This study serves to address this need.

The empirical analysis in the study builds on an output-oriented distance function model and uses a longitudinal panel dataset from 153 hospitals in California.

This study results point to key insights related to output–output tradeoffs along the production frontier. Specifically, the authors find that higher throughput rates may lead to significantly lower levels of experiential quality, and net revenue from operations, accounting for the clinical quality of care. Similarly, the authors’ findings highlight the resource intensity and operational challenges of improving experiential quality of care. In regards to input–output relationships, this study finds diversification of care is associated with increased throughput, improvements in service satisfaction and a corresponding increase in the net revenue from operations.

Highlighting the tradeoffs along the production frontier among the various outcomes of interest (throughput, experiential quality and net revenue from operations), and highlighting the link between diversification of care and care delivery outcomes at the hospital level are key contributions of this study. An understanding of the tradeoffs and returns in healthcare delivery serves to inform policy-making with key managerial implications in the delivery of care.

As the manufacturing activities in today's industries are getting more and more complex, it is required for the manufacturing firm to have a good shop floor production scheduling to plan and schedule their production orders. An accurate scheduling is essential to any manufacturing firm in order to be competitive in global market. The paper aims to discuss these issues.

Two types of shop floors, job shop and cellular layout, were developed by using WITNESS simulation package. Consequently, the performance of forward scheduling and backward scheduling in both job shop and cellular layout was compared using simulation method, and the results were analyzed by using analysis of variance (ANOVA). Through analysis, the best scheduling approach and layout to be used by manufacturing firm in order to achieve the make-to-order (MTO) production and inventory strategy were reported.

The results from simulation show that backward scheduling in job shop layout has the lowest average throughput time, lowest lateness, and highest labour productivity than forward scheduling. While in cellular layout, forward scheduling has the lowest average throughput time, lowest lateness, and highest labour productivity than backward scheduling in all conditions. It shows that the performance of scheduling approach is different in each production layout.

Suitable scheduling approach is needed in manufacturing industry as to maximize production rate and optimize machine and process capability. This paper presents an empirical study about the assembly process of radio cassette player of one manufacturing industry in order to investigate the impact of variety of orders and different number of two workers on the performance of production scheduling approach. Forward scheduling and backward scheduling are used to schedule the production orders.

A number of attempts have been made to develop theories in operations management (OM) (e.g. trade‐off theory by Skinner, customer‐contact model by Chase and Tansik, product‐process matrix by Hayes and Wheelwright). Researchers in OM acknowledge that there is no widely‐accepted theory on which OM rests or which serves as a unified OM theory to integrate existing theory‐like principles or informal theories. Constraints management (CM) has been developed over the past 20 years by consultants and practitioners but has received little attention from OM researchers. The authors believe that constraints management may serve as a broad theory within operations that will allow integration of a great deal of existing OM research. The main objectives of this paper are to propose a construct, throughput orientation, discuss its core dimensions, and develop a theoretical model of CM. The paper also suggests several hypotheses that might be empirically tested to establish CM as a recognized theory in the field of operations management. The paper concludes with suggestions for future research.

This paper aims at analyzing different possible assembly systems, including innovative potential configurations such as the fully flexible assembly systems (FAS), by defining a novel analytical model that focuses on the concept of agility and its impact on the whole system performance, also evaluating the economic convenience in terms of the unit direct production cost.

The authors propose a comparison model derived by Newton’s second law, introducing a quantitative definition of agility (acceleration), resistance of an assembly system to any change of its operative state (inertia) and unit direct production cost (force). Different types of assembly systems (manual, flexible and fully FAS) are analyzed and compared using the proposed model, investigating agility, system inertia and their impact on the unit direct production cost.

The proposed agility definition and the proposed comparison model have been applied considering different sets of parameters as independent variables, such as the number of components to assemble (product model complexity) and the target throughput of the system. The main findings are a series of convenience areas which either, for a given target unit direct production cost (force), defines the most agile system to adopt or, for a given target agility (acceleration), defines the most economical system to adopt, as function of the independent variables.

The novelty of this work is, first, the analytical definition of agility applied to assembly systems and contextualized by means of the definition of the new comparison model. The comparison between different assembly systems on the basis of agility, and by using different sets of independent variables, is a further element of interest. Finally, the resulting convenience areas represent a desirable tool that could be used to optimally choose the most suitable assembly system according to one or more system parameters.

The paper aims to address the modelling and optimization of fully flexible assembly systems (F‐FAS), a new concept in flexible automation recently introduced by the authors.

The paper presents a mathematical model of the F‐FAS, which makes it possible to predict its efficiency, throughput and unit direct production costs, correlating such values with system and production variables. The mathematical model proposed in the paper was derived from experimental and simulation data, which were analysed for a wide range of different productions and system settings.

Correlation analysis revealed that there are three main determinants of the efficiency of the F‐FAS: the number of components (types of parts) used to assemble the models (production variable); the average complexity of the models to be assembled (production variable); the ratio of the average perimeter of components (production variable) over a significant dimension of the working plane (system variable). Such parameters makes it possible to estimate the maximum attainable efficiency of the F‐FAS, and to calculate the optimal setting of the feeder which makes it possible to obtain such efficiency during the execution of the whole production order.

The model presented in the paper makes it possible to quantify in advance the real potential of the F‐FAS, according to the characteristics of the production mix and type of components to be assembled. By using the methodologies presented in the paper, one can first evaluate the convenience of the F‐FAS approach with respect to traditional FAS technology and manual assembly, then identify the optimal design and settings of the F‐FAS, according to the needs of a specific application. As a result, not only can the investment on the automated assembly system be accurately evaluated in advance, but also the return on investment can be maximized.

The purpose of this paper is to analyze the applicability of lean accounting and throughput accounting in a company with considerable investments in advanced manufacturing technology (AMT).

The paper compares lean accounting and throughput accounting with the traditional accounting system the company is using today. The authors investigate the differences between the three alternative approaches and use a case study approach to illustrate the effects of applying different modern accounting approaches in a complex manufacturing setting.

Pair-wise comparisons of the three approaches provide some interesting cost information as to the role of bottlenecks and value streams.

The specific results of this study are limited to the case company, but can hopefully contribute to further research on how to combine lean and throughput accounting for mixed manufacturing environments, involving both value streams and bottlenecks.

Lean and throughput accounting provide other perspectives on cost information to traditional accounting, and can therefore be used in combination. The authors identify some issues and challenges involved in using lean accounting and throughput accounting in an AMT company.

This paper contributes with a comparison of traditional, lean, and throughput accounting in a specific industrial setting characterized by AMT and complex manufacturing.

The purpose of this paper is to investigate the performance of unpaced reliable production lines that are unbalanced in terms of their mean operation times, coefficients of variation and buffer capacities.

Simulations were carried out for five‐ and eight‐station lines with various buffer capacities and degrees of means imbalance. Throughput, idle time and average buffer level performance indicators were generated and statistically analysed.

The results show that an inverted bowl allocation of mean service times, combined with a bowl configuration for coefficients of variation and a decreasing order of buffer sizes results in higher throughput and lower idle times than a balanced line counterpart. In addition, considerable reductions in average inventory levels were consistently obtained when utilizing a configuration of progressively faster stations, coupled with a bowl‐shaped pattern for coefficients of variation and an ascending buffer size order.

The results for these specific experiments imply that resources expended on trying to achieve a balanced line could be better used by seizing upon possible enhanced performance via controlled mean time, variability and buffer imbalance. Results are valid for only the line type and parameter values used (simulation results are specific and not general).

Guidelines are provided on design strategies for allocating labour and capital unevenly in unpaced lines for better performance in terms of increased throughput or lowered idle time or average buffer levels.

This paper might be viewed as one of the first simulation investigations into the performance of unpaced production lines with three sources of imbalance.

The purpose of this paper is to study the various modalities of production outsourcing service and compare three different models, namely: standard accounting, theory of constraints (TOC) and linear programming (LP) enhancement of TOC.

This is a diagnostic study concerned with accurately describing the characteristics of outsourcing phenomenon and defining clearly the objective function and the associated constraints. The optimization models have been constructed and analyzed in a real‐life situation by collecting data with sufficient precision.

This paper brings out distinctively different options for outsourcing services and compares the results with the findings available in literature. The significant finding is that it is an imperative to evaluate the outsourcing approaches from a situational perspective governed by internal and external constraints imposed by competitive forces.

This research does not embrace the sensitivity of various cost parameters as well as the fuzziness of the dynamics of competition.

The models and the analyses would facilitate systemic decision support to production, procurement and marketing managers engaged in the competitive value chain. For successful outsourcing, the business goals must be validated with financial justification. Outsourcing is not only carried out in cases of non‐availability of resources internally, or to meet the peak demand, but also it helps in cash infusion, reduction in operating costs and restructuring of resources.

Manufacturing organizations should not only implement outsourcing in an ad hoc manner but should try to innovate on different outsourcing practices and should make attempts to study and analyze methods that are better and the best to attain competitive advantage.