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To compare the performance of a new hybrid manufacturing system (HMS) with a conventional cellular manufacturing system (CMS). The hybrid system is a combination of the cellular manufacturing and job shop.

A hypothetical manufacturing facility with eight machines and 20 parts is used as a case. Simulation models are developed for two manufacturing systems. A multi‐factor comparison is carried out to test the performance of the systems under different scenarios.

It was found that group scheduling rules (GSR) and the manufacturing system design factors have significant impact on the performance of the system. In particular, the hybrid system shows its best performance when the MSSPT GSR is applied, whereas the cellular system is superior when DDSI is implemented. The results also demonstrate that, by adding non‐family parts to the production schedule of the HMS, significant benefits in the performance measures can be attained.

The conclusion cannot be generalized, as the result is dependent upon the input data and the size of the problem.

The application may be limited to certain industry sectors. Further studies may be needed to identify the appropriate industry.

While the majority of the literature focuses on either a job shop or a pure CMS, this paper has a distinctive approach that allows the combined use of both systems. This could be a useful transitional approach from one system to the other.

Reconfigurable machines tools (RMTs) are gaining momentum as the new solutions to customised products in the manufacturing world. The driving force, among others, behind these machines is the part envelope and the part family of products that they can produce. The purpose of this paper is to propose a new class of RMT known as a reconfigurable guillotine shear and bending press machine (RGS&BPM). A part family of products that this machine can produce is developed using hierarchical clustering methodologies. The development of these part families is guided by the relationship of the parts in the family in terms of complexity and geometry.

Part families cannot be developed in isolation, but that process has to incorporate the machine modules used in the reconfiguration process for producing the parts. Literature was reviewed, and group technology principles explored, to develop a concept that can be used to develop the part families. Matrices were manipulated to generate part families, and this resulted in the development of a dendrogram of six possible part families. A software with a graphic user interface for manipulation was also developed to help generate part families and machine modules. The developed concept will assist in the development of a machine by first developing the part family of products and machine modules required in the variable production process.

The developed concepts assist in the development of a machine by first developing the part family of products and machine modules required in the variable production process. The development of part families for the RGS&BPM is key to developing the machine work envelope and modules to carry out the work. This work has been presented to demonstrate the importance of machine development in conjunction with a part family of products that the machine will produce. The paper develops an approach to manufacturing where part families of products are developed prior to developing the machine. The families of products are then used to develop modules that enable the manufacture of the parts and subsequently the size of the machine.

The research was limited to the development of part families for a new RGS&BPM, which is still under development.

The study reflects the development of reconfigurable machines as a solution to manufacturing challenges in terms of group technology approaches adopted in the design phase. It also highlights the significance of the concepts in the reconfigurable machine tool design. The part families define the machine work envelop and its reconfiguration capability.

The success of the research will usher an alternative to smaller players in sheet metal work. It will contribute to the easy development of the machine that will bridge the high cost of machine tools.

The study contributes to the new approach in sheet metal manufacturing where dedicated machines may be substituted by a highly flexible reconfigurable machine that has a dual operation, making the investment for small to medium enterprises affordable. It also contributes to the body of knowledge in reconfigurable machine development and the framework for such activities, especially in developing countries.

Provide a new technique for forecasting parts usage in remanufacturing operations and describe its application to oil field equipment operations.

New “correlated forecasting preprocessing” equations were derived for extracting additional information from a matrix of historical parts usage data. They were applied to both synthetic data and actual data from a large oil field remanufacturer.

The new equations were effective in extracting the necessary pre‐forecasting data from both synthetic and actual data sets. The key to effective preprocessing is using the correlation information from the entire parts usage matrix rather than just rely on bill of materials relationships.

Accurate forecasting is vital to manufacturing at all levels of aggregation from the smallest part to the entire facility and for all planning horizons from days to years. Forecasting is an operations manager's first line of defense in inventory control. The addition of a preprocessing step makes the application of traditional forecasting methods yield significantly better results.

The concept of using the partial correlations present in a parts usage matrix, instead of attempting to apply bill of material relationships, is new. The resulting preprocessing equations are new. The value of improved forecasting is that it directly impacts manufacturing profitability.

The purpose of this paper is to develop the methodology which can facilitate the concept of reconfiguration in the manufacturing system.

Design methodology includes the calculation of similarity matrix, formation of part family, and selection of part family. ALC algorithm has been used for part family formation and three criteria have been considered for the selection of part family. These criteria are reconfiguration effort, under-utilization cost, and floor space cost. AHP has been used to calculate the weights of criteria and reference ideal method has been used for the selection of alternatives.

In the manufacturing system, machines should be grouped on the basis of reconfiguration cost. When the time period is less, light machines and Group 1 machines are added and removed. In the case study, the concept of reconfiguration is useful for families (A, B, C, D). Machines can be reused by adding/removing some modules of machines. The concept of reconfiguration becomes more useful when it is implemented with lean manufacturing. Lean manufacturing techniques Jidoka and Poka-yoke are used to increase the diagnosability of the system.

Industrial case study has been considered.

Market competition is increasing rapidly and it increases the demand and variety of products, due to which manufacturing enterprises are forced to adapt a manufacturing system which can adjust its capacity and functionality quickly at low cost. To reconfigure manufacturing system from one product/product family to another product/product family, changes can be done in hardware and/or software components in response to sudden changes in the market or in regulatory requirements.

An integrated approach for reconfiguration has been proposed considering the industrial application. It includes weighted Jaccard function, ALCA, AHP, RIM. The methodology for calculation of reconfiguration effort, under-utilization cost, and floor space cost has been presented for industrial case.

The formation of machine‐part families is an important task in the design of cellular and flexible manufacturing systems. The formation results in the creation of many benefits for manufacturing systems. Among the many methods utilized in machine‐cells formation, the similarity coefficient method (SCM) is most widely used. When SCM is used, the rearrangement of machine and part components is required to form machine‐part families. This process of rearrangement has been considered as being subjective and difficult and may result in improper assignments to parts families, resulting in a negation of benefits promised. This paper presents an effective algorithm to identify part‐families and bottleneck‐parts, given machine groupings, rather than addressing the machine grouping problem in general.

In spite of numerous political initiatives, the proportion of self-employed women in Germany has stagnated. This paper aims to offer a new perspective on this problem. The investigation and data gathered about job and life satisfaction of women with families can provide information on the reasons for starting a business, and the low participation of women in entrepreneurial activity.

After a literature review, representative German panel data is analysed to investigate the job and life satisfaction of full- and part-time self-employed women with a family.

Self-employed women with families who work full-time are more satisfied with their jobs than those who work part-time. There is no statistically significant difference between these two groups with respect to their life satisfaction.

An implication of the results suggests new ideas and a new focus by policy makers and politicians when trying to increase the quantity of women with families engaging in self-employment. A limitation is that a lack of “within” variation in the data means that the panel nature of the survey cannot be usefully incorporated into the investigation.

Until now, there is limited research about the work and life satisfaction of women with a family comparing full- and part-time self-employment. This analysis is potentially valuable because the number of part-time self-employed women is substantially higher than the number of full-time self-employed women. We find evidence that such women may instead prefer full-time self-employment.

The grouping of parts and machines for design of cellular manufacturing systems is carried out by clustering analysis. Two major drawbacks of some clustering algorithms have been identified in handling bottleneck machines for forming machine cells. These drawbacks include solution inconsistency and possible misclustering which result in unnecessary bottleneck machines required. Presents a more robust clustering algorithm to overcome these drawbacks. The algorithm consists of four stages: selection of initial cluster centres; cluster‐seeking analysis; eliminating unnecessary bottleneck machines; and new parts assignments. The decision functions based on the formed machine cells are defined to assign new parts to the machine cells. The algorithm is capable of selecting an ideal set of initial cluster centres, and minimizing the number of bottleneck machines required for forming the desired number of machine cells. It can also provide alternative design of machine cells to accommodate the existing production environment.

The purpose of this paper is twofold. In view of the importance of process platform‐based production configuration (PPbPC) in sustaining product family production efficiency, it is to study the underlying logic for configuring production processes for a product family based on a process platform. Second, it is to apply the Petri nets (PNs) techniques to model PPbPC, in attempting to shed light on the underlying logic.

The authors first identify the fundamental issues in PPbPC, including variety handling, process variation accommodation, configuration at different abstraction levels, and constraint satisfaction. To accommodate the corresponding modelling difficulties, the authors develop a formalism of hierarchical colored timed PNs (HCTPNs) based on the principles of hierarchical PNs, timed PNs, and colored PNs. In the formalism, three types of nets together with a system of HCTPNs are defined to address the modelling of PPbPC.

Applying HCTPNs to vibration motors' case has revealed the logic of specifying complete production processes of final products at different levels of abstraction to achieve production configuration. The preliminary results also further demonstrate the feasibility of modelling PPbPC based on HCTPNs.

Traditional approaches to planning production processes for individual products may limit production performance improvement when companies need to timely produce a high variety of customized products. Systematic methods should be developed to plan production processes for product families so as to achieve production efficiency while utilizing the existing manufacturing resources.

By integrating the advantages of existing PN techniques, the HCTPNs formalism is developed to shed light on planning production processes for product families. The resulting production configuration model can facilitate practitioners to achieve production efficiency in producing large numbers of customized products.

Cellular and functional layouts were investigated under a variety of real‐world conditions via a two‐stage computer simulation study. In the first stage, simulation models were developed for three actual companies. Six different cell formation procedures were used to develop the cellular layouts and CRAFT was used to develop the functional layout. The following six variables were used to measure shop performance: average flow time, maximum flow time, average distance travelled by a batch, average work‐in‐process level, the maximum level of work‐in‐process, and the longest average queue. Factors observed in the first stage of the study that appear to make cellular manufacturing less beneficial than might otherwise be expected were found to be small batch sizes, a small number of different machines the parts require in their processing, short processing times per part, the existence of bottleneck machines (i.e. machines with insufficient capacity), and the absence of natural part families (i.e. sets of parts with similar processing requirements). In the second stage of this study, earlier assumptions associated with sequence‐dependent setup times and move time delays were relaxed. These two parameters were identified as important factors as well.

Presents the similarity coefficient method for group technology to alleviate the part family formation problem in flexible manufacturing systems (FMS). Part families are formed in FMS in order to take advantage of part similarities in design and manufacture. Parts coding and classification analysis (PCA) has constituted the bulk of part family formation techniques in practice. Using shape‐based features for grouping is very labour intensive at the coding and classification stages. As a means of alleviating the latter problem, presents an approach for converting the weighted codes of the PCA to similarity coefficient measures. Uses a clustering algorithm to identify the part families. Presents a numerical example that compares the single and average linkage clustering technologies. An experimental investigation of the two methods showed that the average linkage clustering (ALC) performs better than the single linkage clustering (SLC) technology in minimizing intercellular materials handling costs.