Endüstri Mühendisliği Bölümü Yayın Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/279

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  • Conference Object
    Forecasting Day of Week Volume Fluctuations in the Intermodal Freight Transportation
    (Institute of Industrial Engineers, 2011) Ertem, M.A.; Ertem, Mustafa Alp; Endüstri Mühendisliği
    Average daily volume fluctuates intensely based on the day of week in the intermodal freight transportation. Shippers tend to peak around Thursdays and receivers tend to peak around Mondays. These fluctuations bring challenges to the industry in terms of capacity management and getting reliable service from the railroad companies. The purpose of this study is to forecast J. B. Hunt Transport Services, Inc.'s load volume on railroads. Load is meant to be the number of containers that will arrive at a rail ramp during a 24hrs time window. The end in mind is to have better service from the railroad companies and to manage the company owned equipment better. The forecasting model applied to tackle this problem is a multiple linear regression model and is based on the historical in-gate numbers. It uses the previous two year's data and day of week information as independent variables, and current year's data as the response variable. The results indicate better accuracy levels for the model when compared to the two week moving average.
  • Article
    Citation - WoS: 7
    Citation - Scopus: 11
    A Warehouse Design With Containers for Humanitarian Logistics: A Real-Life Implementation From Turkey
    (Univ Cincinnati industrial Engineering, 2019) Sahin-Arslan, Aysenur; Ertem, Mustafa Alp; Ertem, Mustafa Alp; Endüstri Mühendisliği
    The purpose of this study is to investigate how and at what cost freight containers could be used as an inventory holding mechanism for humanitarian logistics. The layout and cost comparison of two alternatives are performed-stocking in a warehouse and material storage in containers. An optimum layout for storage in containers is proposed. It was found that container stockpiling uses the available area and space better than the warehouse option to stock the same number of material pallets. Leasing and purchasing costs of these alternatives are compared using present worth analysis. The results revealed that the container leasing option is not cost effective when land cost is included. Warehouse leasing results in the least setup cost, however, it incurs more operating costs, including lighting, ventilation, and maintenance as well as handling of the pallets. A real-life implementation of the proposed container stockpiling idea is presented for Turkey.
  • Conference Object
    Citation - Scopus: 1
    Multi-Manned Assembly Line Balancing Problems With Sequence-Dependent Setup Times
    (Curran Associates Inc., 2017) Güner, F.; Güner, Funda; Kellegöz, T.; Toklu, B.; Çankaya Meslek Yüksekokulu
    In the production of large-size products (such as automobiles, buses, trucks etc.), designing assembly lines with multi-manned workstations may provide decreasing number of total workstations, requirement of large plant area and product flow time. Depending on the characteristics of the tasks about to be started and the one just completed on the same worker, setup times may be significant. Therefore, in some real life situations, it is possible to see setup times between tasks processed successively. In this study, assembly line balancing problems with multi-manned workstations and sequence dependent setup times are addressed. The formal definition of the problem is firstly presented. Then, its mixed integer programming formulation and is developed. In the computational study, by using these formulations, a set of test instances is solved, and results are provided.
  • Article
    Kamu Kurumlarında Risk Değerlendirmesi İçin Karar Destek Sistemi Önerisi
    (2018) Tok, Elif Gülce; Satır, Benhür
    6331 Sayılı İş Sağlığı ve Güvenliği (İSG) Kanunu’nun 31.12.2012’de yürürlüğegirmesinden itibaren risk değerlendirmesi bütün işyerlerinde zorunlu halegelmiştir. Bu çalışmada iş sağlığı ve güvenliğinin önemli bir öğesi olan riskdeğerlendirmesinin kamu kurumlarında yapılmasını daha sağlıklı hale getirecekve kolaylaştıracak bir rehber hazırlanmıştır. Bu rehber bir kontrol listesi ve ilgilirisk tablosundan oluşmaktadır. Gerek ülkemizdeki 6331 Sayılı İSG Kanununda veilgili yönetmeliklerde, gerekse de OHSAS 18001 İSG Yönetim Sisteminde, sürekliiyileştirmenin önemi açıkça görülmektedir. Bu çalışmada hazırlanan rehberinuygulanmasında riskin kabul edilebilir seviyeye inene kadar risk değerlendirmesiniizlemeyi sistemli ve kolay hale getirerek sürekli iyileştirmenin gereklerini sağlamaküzere bir Karar Destek Sistemi önerilmiştir. Birim, kaynak ve tehlike parametreleribir bütün olarak ele alınarak BKT olarak değerlendirilmiş ve sistemin veri tabanıaltyapısı bunun üzerine kurulmuştur. Risk değerlendirmesinin ana öğeleri olan BKT,risk ve önlem ilişkilerinin Varlık-İlişki Çiziti hazırlanarak en büyük ve en küçükkardinallik oranları her ilişki arasında tanımlanmıştır. Fikir vermesi açısından bazı kullanıcı arayüzleri tasarlanmış ve önerilmiştir. Farklı sektörlerde yapılmış benzerçalışmalar mevcuttur ancak gerek kamu kurumları düşünüldüğünde gerekse deuygulama için önerilen karar destek sistemi düşünüldüğünde bu çalışma bilgimizdahilinde literatürdeki ilk çalışmadır.
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    Modeling Dry and Wet Spells of Central Anatolia Region of Turkey
    (2011) Yıldırım, Fetih; Bayrak, Özlem Türker
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  • Conference Object
    Improving Evaluation System of Program Educational Objectives and Outcomes based on MÜDEK Criteria Using Fuzzy Approach
    (2015) Başkır, Mükerrem Bahar; Yıldırım, Gonca; Yıldırım, Fetih
  • Conference Object
    An optimization model for worker assignment of a mixed model vehicle production assembly line under worker mobility
    (2011) Karabak, Funda; Güner, Nizamettin Doğan; Satır, Benhür; Kandiller, Levent; Gürsoy, I.
    In this study, we consider the problem of worker assignment in a mixed model vehicle production assembly line. In particular, we focus on large size vehicles like busses and trucks that have multi zones in which workers can perform their assigned tasks simultaneously. This situation requires balancing the workloads of workers assigned in a certain set of workstations. Over the assembly line, it is allowed that workers may change their workstations during the same cycle. Moreover, each worker has a certain skill level which configures the possible set of tasks to be undertaken. Scale of the product, worker mobility and skill differences make the studied problem complicated. We propose a worker assignment model and develop a heuristic algorithm whose performance is to be evaluated against the optimal seeking methods in terms of small sized problems. We report on the validation of our heuristic algorithm in real …
  • Article
    Broiler House Performance Analysis and Chick Entrance Planning for a Broiler Chicken Integration
    (2012) Satır, Benhür; Yıldırım, Gonca; Kırca, Ömer
    Increasing rates of chicken meat production has a substantial impact on the Turkish economy. Per capita production in Turkey is close to the average production of the top 20 countries in the world. The production is done by integrated organizations, incorporating an integrator chicken company affiliated with all aspects of the production in an organization. There are many complicated processes, stages and parties involved in a typical integration, bringing with them many interesting problems. In this paper, we focus on tactical and operational decisions required during the broiler growing stage, motivated by the requirements of a moderate-sized integrator in the Marmara Region of Turkey. We use analysis of variance to compare the performances of available broiler houses, and to find the factors effecting the performance measures. Then, we present a mixed-integer linear program which uses the results of our performance analysis to find the least costly set of broiler houses with which the integrator should work, and the chick entrance times into these houses over a planning period.