Experimental Design of a Flexible Manufacturing System

Abstract Flexible Manufacturing Systems (FMS) deal with varied part and product designs, and allows variation in parts' processing sequences and production volume change. Its successful implementation results in improvement of capital utilization, higher profit margins, and increased competitiveness. Today, FMS design is complex, where various layout types and material handling system (MHS) devices exist while part inter-arrival and processing times are stochastic. This paper presents a case study to investigate effects of different input factors, including layout and MHS configuration (number, speed and type) on FMS performance measured by total production cost, total flow time and throughput, using simulation. The investigation includes interactions between input factors and identifies the settings that yield optimal performance. Overall, the paper presents a framework that integrates experimental design, simulation, and multi-criteria decision-making to the design of complex manufacturing systems

Outcome of allogeneic stem cell transplantation with a conditioning regimen of busulfan, cyclophosphamide and low-dose etoposide for children with myelodysplastic syndrome

BACKGROUND AND OBJECTIVESAllogeneic stem cell transplantation (SCT) offers the best chance of cure and long-term survival for children with myelodysplastic syndromes (MDS).DESIGN AND SETTINGRetrospective analysis of pediatric patients with primary MDS treated with allogeneic SCT at a single institution treated between January 1993 and December 2008.PATIENTS AND METHODSOf 16 consecutive children who received allogeneic SCT for treatment of MDS in our center, 14 patients met the criteria of MDS according WHO I and II criteria. The median age was 4.8years (range, 1-14 years) and 64% were male. The median time from diagnosis to transplant was 6 months. MDS stage was refractory cytopenia (RC) in 9, refractory anemia with excess blasts (RAEB) in 5. Monosomy 7 was present in 35% of the patients. The majority of patients (11/14) were conditioned with a busulfan-based myeloablative (MA) regimen with addition of low-dose of etoposide (30mg/kg). All but one received a bone marrow graft.RESULTSNine patients achieved complete remission (CR), and seven remain alive. At a median follow-up of 3 years (range, 2-14 years) the OS and EFS was 57% (95%CI, 0.28-0.78). Cumulative EFS at 1 0 years was 43% (95% CI: 0.14-0.70). Relapse-related mortality was 21.4%; nonrelapse mortality (NRM) was 28.57%. All the survivors had etoposide in their conditioning regimen. Patients younger than 1 0 years had better survival (P=.001).CONCLUSIONChildren with MDS achieve encouraging OS and EFS following allogeneic SCT. A busulfan-based regimen with a lower dose of etoposide is an effective and less toxic regimen. The outcomes are best in younger patients

A New Association Analysis-Based Method for Enhancing Maintenance and Repair in Manufacturing

Maintenance and quality of products are absolutely crucial for any organization to succeed in the industrial and manufacturing engineering. Current research studies have confirmed the presence of a high correlation between these two factors, namely maintenance and quality of products, in industrial organizations. Nevertheless, no extensive research has been conducted in order to study the link between maintenance and the quality of products in manufacturing. In this paper, we conduct a study in this domain and examine the relationship patterns between maintenance and the quality of product using manufacturing data on maintenance and the product quality. Specifically, we employ association analysis and association rule mining with large and extensive sets of product quality, repair, and maintenance data. Our main objective is to discover interesting and non-trivial associations for feature failure resulting in the repair or maintenance of a product with unapproved quality. The results of evaluation are quite interesting. The resulting association rules with high values of confidence and lift suggest some essential associations between the product features and the failure; such findings have not been known and used before. This can help quality engineers and maintenance teams to enhance maintenance and repair operations and lower the overall cost of manufacturing

A Model for Maintenance Planning and Process Quality Control Optimization Based on EWMA and CUSUM Control Charts

The performance of a production system is highly dependent on the smooth operation of various equipment and processes. Thus, reducing failures of the equipment and processes in a cost-effective manner improves overall performance; this is often achieved by carrying out maintenance and quality control policies. In this study, an integrated optimization method that addresses both maintenance strategies and quality control practices is proposed using an exponentially weighted moving average (EWMA) chart, in which both corrective and preventive maintenance policies are considered. The integrated model has been proposed to find optimal decision variables of both the process quality decision parameters and the optimal interval of preventive maintenance (i.e., Ns, Hs, L, λ, and t_PM) to result in overall optimal expected hourly total system costs. A case study is then utilized to investigate the impact of cost criteria on the proposed integrated model and to compare the proposed model with a model using the cumulative sum (CUSUM) control chart. The improved model outputs indicate that there is a reduction of 34.6% in the total expected costs compared with those of the other model using the CUSUM chart. Finally, an analysis of sensitivity to present the effectiveness of the model parameters and the main variables in the overall costs of the system is provided

Is secondary hemophagocytic lymphohistiocytosis behind the high fatality rate in Middle East respiratory syndrome corona virus?

Middle East respiratory syndrome corona virus (MERS-CoV) is becoming a major health concern in Saudi Arabia resulting in an associated high case fatality. The rapid deterioration of vital organs functions and high mortality rate seen in MERS-CoV has been observed previously in Epstein-Barr virus (EBV), severe acute respiratory syndrome caused by a coronavirus (SARS-CoV) and avian and bird flu-related hemophagocytic lymphohistiocytosis (HLH). There are many reports of successful treatments for severe cases of EBV-HLH using HLH-94/2004-type immunochemotherapy with etoposide as a pro-apoptotic agent. The use of immunochemotherapy in severe MERS-CoV-related HLH merits an urgent investigation in a well-designed clinical trial

Methods in Product Design: New Strategies in Reengineering

Karena industri mengadopsi strategi pengembangan produk yang berfokus pada konsumen, mereka harus menawarkan rentang produk yang lebih luas dalam waktu desain yang lebih singkat dan proses yang dapat diproduksi dalam ukuran lot yang sewenang-wenang. Selain itu, mereka perlu menerapkan metode dan alat canggih untuk dengan mudah melakukan desain produk awal dan analisis trade-off pengembangan di antara tujuan yang bersaing. Metode dalam Desain Produk: Strategi Baru dalam Rekayasa Ulang memberikan wawasan tentang metode dan teknik yang memungkinkan penerapan filosofi desain produk yang berfokus pada konsumen dengan mengintegrasikan kemampuan desain dan pengembangan dengan sistem berbasis komputer yang cerdas. Buku ini mendefinisikan desain yang berfokus pada pelanggan dan membahas cara untuk menilai permintaan dan sumber yang berubah, dan menggali apa yang dibutuhkan untuk berhasil memproduksi barang di pasar yang menuntut. Ini meninjau metode yang telah terbukti untuk menilai kebutuhan pelanggan. Kemudian, setelah menunjukkan bagaimana perubahan kebutuhan berdampak pada rekayasa ulang produk, ini menjelaskan bagaimana perubahan dapat dicapai secara efisien. Ini merinci bagaimana kemajuan TI dan teknologi mendukung pengembangan produk yang berfokus pada pelanggan, membahas prinsip kustomisasi massal mutakhir yang memaksimalkan produksi hemat biaya, dan menggambarkan bagaimana menerapkan kebijakan pemeliharaan prediktif yang efektif. Metode dalam Desain Produk: Strategi Baru dalam Rekayasa Ulang menyediakan metode, teknologi mutakhir, dan strategi baru untuk desain dan pengembangan produk yang berfokus pada pelanggan yang memungkinkan organisasi untuk dengan cepat merespons pasar global yang menuntut

Clinical characteristics and treatment outcome of pediatric patients with chronic myeloid leukemia

As chronic myeloid leukemia is rare in children, most data on imatinib mesylate therapy is derived from adult studies. We retrospectively evaluated pediatric (\u3c14 years) patients with Ph+ chronic myeloid leukemia treated with imatinib mesylate, from January 2003 through June 2008. Of the 12 chronic myeloid leukemia patients (2% of all leukemias) 11 were in chronic phase while one had myeloid blast crisis. Six subsequently underwent stem cell transplantation. Five patients had grade 3-4 arthralgia requiring therapy alteration. None achieved complete molecular remission (MR) with imatinib mesylate alone. In contrast 3/6 patients post stem cell transplantation have undetectable BCR-ABL. Three patients relapsed to chronic phase (1 imatinib mesylate; 2 stem cell transplantation). Relapse free survival is 65.6% at four years and all are alive. Imatinib mesylate is effective therapy for children with chronic myeloid leukemia. However, cure probably requires stem cell transplantation. Acute toxicity of imatinib mesylate is tolerable, but long-term effects on growing children are unknown. Pediatric patients with chronic myeloid leukemia should undergo stem cell transplantation when appropriate related donors are available

Clinical characteristics and treatment outcome of pediatric patients with chronic myeloid leukemia

As chronic myeloid leukemia is rare in children, most data on imatinib mesylate therapy is derived from adult studies. We retrospectively evaluated pediatric (<14 years) patients with Ph+ chronic myeloid leukemia treated with imatinib mesylate, from January 2003 through June 2008. Of the 12 chronic myeloid leukemia patients (2% of all leukemias) 11 were in chronic phase while one had myeloid blast crisis. Six subsequently underwent stem cell transplantation. Five patients had grade 3–4 arthralgia requiring therapy alteration. None achieved complete molecular remission (MR) with imatinib mesylate alone. In contrast 3/6 patients post stem cell transplantation have undetectable BCR-ABL. Three patients relapsed to chronic phase (1 imatinib mesylate; 2 stem cell transplantation). Relapse free survival is 65.6% at four years and all are alive. Imatinib mesylate is effective therapy for children with chronic myeloid leukemia. However, cure probably requires stem cell transplantation. Acute toxicity of imatinib mesylate is tolerable, but long-term effects on growing children are unknown. Pediatric patients with chronic myeloid leukemia should undergo stem cell transplantation when appropriate related donors are available