Industrial Engineering

Methods. -Plasma levels of IFN-c were assayed in 29 FMF patients in attack-free period (mean age: 32, min-max: 17-48; male/female: 10/19), 18 FMF patients with acute FMF attack (mean age: 32, min-max: 19-50; male/female: 8/10), and 19 healthy controls (mean age: 31.94 ± 1.50, min-max: 23-42; male/female: 11/8). IFN-c levels were also compared among colchicine treated and untreated groups.

A completely safe engineering solution to the automotive assembly line knuckle ball-joint pull-out problem is achieved using failure analysis based on the “Design of Experiment” (DOE) method. During use, some ball-joints move in their housings or come loose under heavy loads. The purpose of this study is to determine critical production parameters that will eliminate this failure. In this research, the knuckle-ball-joint pull-out problem is examined, and knuckle housing and ball-joint outer diameter limits are re-defined. Four levels of interference between knuckle and ball-joint diameters and 2 levels of knuckle thickness are specified. Experiments are repeated five times using General Variance Analysis. Required pull-out force is determined, and necessary interference is found. New knuckle housing and ball-joint diameters, based on recommended interference values, are determined. It is also found that thickness of knuckle boss does not affect the results. Therefore, the design is unchanged in this region and this reduces costs.

Taguchi method is one of the most frequently used tools for improving quality. However, most published applications have been concerned with the optimization of a single performance characteristic. In this study, three different methods are used to improve a production prosess with multiple performance characteristics and results are evaluated.

— Because of the phenomenal rise in information, future forecasting systems about strategy development were needed in each area. Therefore, data mining techniques are used extensively in banking area such as many areas. In this study, conducted in banking sector, it was aimed to reduce the rate of risk in decision making to a minimum via analysis of existing personal loan customers and estimate potential customers' payment performances with k-means method is one of the clustering techniques and the decision trees method which is one of the models of classification in data mining. In the study, SPSS Clementine was used as a software of data mining and an application was done for evaluation of personal loan customers.

Induction hardening is often used in the automotive sector to give steel superior mechanical properties. Compared to steel, induction-hardened AISI 1040 steel has higher hardness and better toughness. In the hardening process, various operating variables (e.g., power supply, scan rate, distance between work-piece and coil) are considered and optimized using the Taguchi approach. An L27 orthogonal array is chosen for the experimental design based on the operating variables and their levels. These optimized operating variables improved surface hardness and core toughness under industrial conditions. The formation of martensite is expected for suitable operating parameters. Due to the transformed/developed structure of the AISI 1040 steel, the response variables (i.e., surface hardness, case depth) are measured following the induction hardening process. Signal-to-noise (S/N) ratios and analysis of variance (ANOVA) were employed to determine the optimal process conditions and significant operating variables, respectively. As a result of the analyses, the optimization of the operating variables for induction-hardened AISI 1040 steel is investigated. The results from using the optimal operating variables changed from 55 HRc to 18 HRc on the surface of the steel compared to the core. As a consequence of the optimization, light and scanning electron microscopy are performed to determine the effects of the hardness from the outer surface to the center. Transformations associated with structural changes are investigated, and the results are discussed.

The performance evaluation of companies is an important issue. Balanced Scorecard (BSC) and Six Sigma approaches are widely in use in business in this context. In this study, BSC and Six Sigma performance management systems have been elaborated, their strengths, which can be used in practice by a number of enterprises in a variety of sizes, have been identified; and a new hybrid model of performance measurement system has been developed by merging together the aspects of both management systems that complement each other. The hybrid system can be expressed in terms of operational availability data, and can compare performance qualifications. In practice, performance measurement results obtained for five critical branch offices of a logistics business, by applying the model for operations/processes from the perspectives of Costs, Internal Processes, Customer and System Development and Assessment have been compared by model performance and model efficiency, and the results achieved have been scrutinized.

In this article, the strategy followed by an automobile company for detecting the root causes of groan complaints related to rear drum brakes in commercial vehicles is presented using data collected from the sold troubled vehicles and from new vehicles from the production line, as well as the drum-brake test rig at the laboratory. Drum brake groan is often very intense and can cause large numbers of customer complaints. During a groan noise event, vehicle structure and suspension components are excited by the brake system and result in a violent event that can be heard and felt during brake application. This paper condenses experimental studies on a low frequency drum brake groan problem that has caused high warranty costs. First, the environmental conditions causing the groan were identified and the groan was reproduced. Vehicle tests were performed both at the factory and in traffic. To conclude the planned study, TVA (Total Value Analysis) and FMEA (Failure Mode and Effects Analysis) methods were used effectively. A strategy to determine the root causes was planned and implemented systematically to eliminate the secondary and tertiary effects of brake groan problems. In order to ge to the root causes, vibration and groan measurements were executed and interpreted according to TVA and FMEA charts. The sensitivity of the lining material of the brake shoes to different environmental conditions was investigated. Finally, the groan mechanism of the drum brake system is discussed and the solution to the low frequency drum brake groan problem is evaluated in detail.

Öz
Türkiye'de son 10 yılda inşaat sektörü hızlı bir gelişme göstermiştir. Artan kâr oranları yatırımcıların bu sektöre olan ilgisini yükseltmiştir. Hatta sanayi sektöründe faaliyet gösteren pek çok firma inşaat sektöründeki pastadan pay almak için büyük projelere ve ortaklıklara dâhil olmuşlardır. Kapitalist sistemde, yüksek karlar kısa vadede çekici bir unsur gibi görünmekle birlikte uzun vadede geri dönüşü olmayan bir hasara neden olacaktır. Bunların başında tarım arazilerinin kaybı ve yeşil alanların beton ormanlarına dönüştürülmesi, İstanbul gibi bir şehrin siluetinin bozulması düşünülebilir. Bu çalışmada, Türkiye'de farklı illerde doğayla bütünleşmiş düşük katlı binalar/villalar inşa eden bir firma incelenmiştir. Firma, ankastre serisine buzdolabı da ilave ederek, sektörde rekabet avantajı elde etmeyi ve müşteri taleplerini artırmayı amaçlamaktadır. Ancak firma bunu yaparken kâr oranını düşürmek istememekte, hedef kitlesi olan müşterilerinin dikkatini çekecek bir tercih yapmayı arzu etmektedir. Çok sayıda artan ve azalan kriterin bir arada değerlendirilmesi için çok kriterli karar verme tekniklerinden biri olan VİKOR metodunun kullanılması uygun görülmüştür. Kriter ağırlıklarının sübjektifliğinin azaltılması amacıyla da AHP tekniği kullanılmıştır. Sonuçlar yönetim kurulu başkanı, mimarlar, satış müdürü, muhasebe müdürü ve pazarlama koordinatörü tarafından değerlendirilerek, uzlaşık bir karara ulaşılmıştır.
Abstract In the last 10 years in Turkey, the construction sector has shown a rapid development. Increasing profit rates have raised the interest of investors in this sector. In fact, many companies operating in the industrial sector have been involved in major projects and partnerships to obtain a share of the pie in the construction sector. In capitalist system while

One of the best methods of waste recycling in the construction sector is to employ it in concrete or mortar preparation. In this study, recycled concrete aggregate and bottom ash were used as aggregates in the mortar. Additionaly, expanded perlite which is a material providing lightness, heat insulation and fire resistance, was also used as aggregate. Calcium aluminate cement was preferred as binder to improve fire resistance. Results were obtained and evaluated in terms of flexural and compressive strength, dry unit weight, water absorption, capillarity, thermal conductivity, thermal resistance and cost by following a Taguchi method to internal curing, cement quantity and aggregate ratio as parameters.

İşletmeler, olağanüstü rekabetin yaşandığı günümüz piyasa şartlarında, maliyetleri minimize, kârı maksimize edecek etkin stok politikalarını geliştirmek ve uygulamak zorundadır. Stoklar, üretim işletmelerinin toplam varlıklarının içinde önemli bir yere sahiptir. Bu önemli kalem için etkin stok kontrol ve yönetim politikalarının uygulanması, işletmenin geleceği için büyük önem taşımaktadır. Bu çalışma kapsamında, büyük bir holdingin kimyasallar grubunda faaliyet gösteren bir işletmesinde öncelikle stok kontrol yöntemlerinden ABC analizi uygulanmıştır. İkinci olarak stokların çok kriterli olarak sınıflandırılması için öncelikle Bulanık Analitik Hiyerarşi Prosesi (BAHP) yöntemi ile kriter ağırlıkları belirlenmiş ve İdeal Çözüme Yakınlığa Göre Tercih Sıralama Tekniği (TOPSIS) yöntemi kullanılarak stok kalemleri önem derecelerine göre sıralanmıştır. Çalışmanın sonunda stokların sınıflandırılmasında klasik ABC analizi ve BAHP-TOPSIS yöntemlerinin sonuçları arasındaki farklılıklar ortaya konmuştur. In today's competitive market conditions, organizations have to develop and implement effective inventory policies to minimize their costs, and maximize profit. Inventories have an important place in the total assets of production enterprises. Applying efficient inventory control and management policies for this significant item is very important for the future of the organizations. In this paper, initially an ABC analysis method had been applied to a firm operating at the chemical group of a conglomerate. Then, to classify the inventory as multi criteria; primarily criteria weights are determined by the fuzzy analytic hierarchy process (FAHP) and then stock keeping units are ranked according to their significances with Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method. Finally, the differences are presented between classical ABC analysis and FAHP-TOPSIS results for classifying the inventories.

This paper deals with the application of six sigma methodology for optimization of a cardan shaft. The aim of this optimization is to reduce vibration of the drive shaft and consequently improve vibration noise harshness of the vehicle. The six sigma methodology has been applied to a light truck, which has received excessive vibration and noise complaints. The define-measure-analyze-improve-control approach has been followed to enhance the vibration noise harshness statistics. The result shows that all expected vibration noise harshness performance targets have been dramatically improved when compared to the initial values. As a conclusion, the case study on a light truck is a useful reference to improve vehicle performance for vibration noise harshness.