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One fundamental problem in cellular manufacturing is the formation of product families and machine cells. Many solution methods have been developed for the cell formation problem. Since efficient grouping is the prerequisite of a successful Cellular Manufacturing installation the research in this area will likely be continued. In this paper, we consider the problem of cell formation in cellular manufacturing systems with the objective of maximizing the grouping efficacy. We propose a Genetic Algorithm (GA) to obtain machine-cells and part-families. Developed GA has three different selection and crossover operators. The proper operators and parameters of the GA were determined by design of experiments. A set of 15 test problems with various sizes drawn from the literature is used to test the performance of the proposed algorithm. The corresponding results are compared to several well-known algorithms published. The comparative study shows that the proposed GA improves the grouping efficacy for 40% of the test problems.

Volatile market conditions have made classical production organizations obsolete in the 1990s. Therefore, new means such as holonic, fractal and multi-channel production systems are investigated to enhance manufacturers' dynamic response ability and competitiveness. Amongst these, newly suggested multi-channel manufacturing (MCM) systems compromise compatibility and specialization to produce a certain range of products. This study proposes a new approach based on genetic algorithms to devise such production channels. Feasible solutions corresponding to machine sequences for channels are coded as chromosome structures. Applying genetic operations to these chromosomes created improved arrangements regarding a problem given in the literature. Furthermore, an effective and realistic solution for a real life problem was found by making use of the multi-objective fitness function developed.

Patients are getting in trouble with care processes due to waste and diversity in health care services. Although patients feel uncomfortable with these problems, service providers do not deal with their complaints promptly due to excessive workload and organizational disorder. The aim of this study is to implement lean techniques to solve the operational problems of a public hospital physical therapy and rehabilitation service in Eskisehir, Turkey. The process is analyzed both from the patient and service provider perspectives simultaneously in lean consumption context. Genchi gembutsu, value stream mapping (VSM), integrated consumption and provision map, A3 and heijunka were the lean techniques used. Mapping of the system gives the opportunity to relax the organizational complexity. Consequently, cognitive load of nurses is decreased with daily and weekly assignment algorithms designed as part of heijunka implementation. Also 26.84% of patient flow time and 14.28% of process step reduction are recorded as a result of realized improvements. Hastalar sağlık hizmetlerindeki israf ve değişkenlik nedeniyle bakım süreçlerinde sorunlar yaşamaktadır. Hastaların bu problemler nedeniyle yaşadıkları rahatsızlığa rağmen, hizmet sağlayıcılar aşırı işyükü ve örgütsel kargaşa nedeniyle şikayetler ile ivedilikle ilgilenememektedir. Bu çalışmanın amacı Türkiye'de Eskişehir ilinde hizmet veren bir kamu hastanesinin Fizik Tedavi ve Rehabilitasyon servisinde yaşanan operasyonel problemlerin çözümünde yalın tekniklerin uygulanmasıdır. Süreç, yalın tüketim bağlamında hem hasta hem de hizmet sağlayıcı bakış açısından eş zamanlı olarak analiz edilmiştir. Genchi gembutsu, değer akış haritalama (DAH), bütünleşik tüketim ve tedarik haritası, A3 ve heijunka bu çalışma kapsamında kullanılan yalın tekniklerdir. Sistemin haritalandırılması örgütsel karmaşıklığın çözülmesi için fırsat sunmaktadır. Sonuç olarak, heijunka uygulaması kapsamında tasarlanan günlük ve haftalık atama algoritmaları ile hemşirelerin bilişsel yükü azaltılmıştır. Ayrıca gerçekleştirilen iyileştirmeler sonucunda hasta akış süresinde %26.84, süreç adımlarında ise %14.28 azalma kaydedilmiştir.