TR Dizin
Permanent URI for this collectionhttps://acikarsiv.thk.edu.tr/handle/123456789/2551
Browse
Publication 2014-2020 Yılları Arasında Muhasebe Ve Finansman Dergisi’nde Yayınlanan Makalelerin Bibliyometrik Profilinin İncelenmesi(2021) Funda KARAASLANOĞLU Elif Tuğba ŞAHİN; Şahin, Elif Tuğba; Karaaslanoğlu, Funda; Türk Hava Kurumu Üniversitesi, İşletme Fakültesi, Ankara, Türkiye Türk Hava Kurumu Üniversitesi, İşletme Fakültesi, Ankara, TürkiyeBu çalışmada, 2014-2020 yılları arasında muhasebe ve finans alanının öncül dergilerinden Muhasebe ve Finansman Dergisi’nde yer alan makalelerin, çeşitli parametreler çerçevesinde bibliyometrik özelliklerinin belirlenmesi amaçlanmaktadır. Çalışmada, içerik analizi yöntemi ile 370 makale incelenerek mevcut durum ortaya konulmuştur. Araştırma bulgularına göre, en çok makalenin 2020 yılı, en az makalenin 2014 yılında yayınlandığı; makalelerde nitel araştırma yöntemlerinin nicel araştırma yöntemlerine oranla daha fazla kullanıldığı tespit edilmiştir. İçerik Analizi ve Örnek Olay Analizi, makalelerde en çok kullanılan analiz teknikleridir. Yayınlanan makalelerin sayfa sayılarının en az 12, en çok 32 olduğu, makalelerde yerli kaynaklardan daha fazla yabancı kaynaklardan yararlanıldığı tespit edilmiştir. Makalelerin en çok Uludağ Üniversitesi, Dokuz Eylül Üniversitesi ve Burdur Mehmet Akif Ersoy Üniversitesi’nde çalışan yazarlar tarafından hazırlandığı, yayınlanan 370 makale içinde en az 2014 yılında 136 ve en fazla 2020 yılında 250 anahtar kelime olmak üzere toplamda 1.393 anahtar kelime kullanıldığı belirlenmiştir. En fazla çalışmanın Doktor Öğretim Üyeleri tarafından yazıldığı belirlenmiştir.Publication A GENERIC STRATEGIC SUPPLIER SELECTION MODEL IN INFORMATION AND COMMUNICATION TECHNOLOGIES(2019) Ali Emre KARAÖZ Kemal TEKİN Göknur Arzu AKYÜZ; Türk Hava Kurumu Üniversitesi Diğer Türk Hava Kurumu ÜniversitesiThe topic of supplier rating and selection has gained strategic importance in supply chain management,and supplier selection process is considered as a multi-criteria decision-making issue in the literature. This studyfocuses on the strategic supplier selection for the suppliers providing goods and services in information andcommunication technologies (ICT) sector. A comparative analysis is made in the case company. During theanalysis, a mapping of the criteria used in the case company onto the criteria existing in the literature is made,and the comparative study is performed with two different weight sets. It is revealed that the results from theproposed integrated TOPSIS – [ANP-TOPSIS] approach resulted in more discriminatory results. Based on thecomparative approach used and the need for a decision support system, a generic model for supplier selection anda conceptual design of a decision support system in connection with this generic model are suggested.Publication A MIXED-INTEGER PROGRAMMING MODEL FOR THE JOB SCHEDULING PROBLEM IN A PRODUCTION COMPANY(2022) Durdu Hakan UTKU Karanfil ÖZYİĞİT Esra Yağmur FARİZOĞLU; Türk Hava Kurumu Üniversitesi, Mühendislik Fakültesi, Endüstri Mühendisliği Bölümü, Ankara, Türkiye Türk Hava Kurumu Üniversitesi, Mühendislik Fakültesi, Endüstri Mühendisliği Bölümü, Ankara, Türkiye Türk Hava Kurumu Üniversitesi, Mühendislik Fakültesi, Endüstri Mühendisliği Bölümü, Ankara, TürkiyePurpose: In this study, a mixed-integer programming model is developed to minimize the total lateness and total completion time of the jobs in an automotive company. In order to respond rapidly to the continuous customer demand through the production, the work schedule of engineers in the research and development department is considered flexibly. Methodology: In the study, the mixed-integer programming model is supported by the analytical hierarchy process model to determine the weighted values of total tardiness and total completion times. The developed model is applied to the automotive company using the real data and the problem is solved using the GAMS CPLEX 24.1.3 software. Findings: In this job scheduling problem, the total completion time is decreased to 622 hours from 10149 hours, maximum tardiness is decreased to 9 hours from 104 hours and total tardiness is decreased to 13 hours from 860 hours by using the proposed model. Originality: The proposed model is used for the job scheduling purpose in compliance with the structure of the automotive industry company using the machine scheduling modeling principles and Analytical Hierarchy Process together. Keywords: Parallel Machine Scheduling, Optimization, Mixed Integer Programming, Analytical Hierarchical Process.Publication A Monte Carlo-based Poisson's equation solver parallelized with Coarray Fortran(The Scientific and Technological Research Council of Turkey (TUBITAK-ULAKBIM) - DIGITAL COMMONS JOURNALS, 2016) Nevsan ŞENGİL; Özgür TÜMÜKLÜ; Mehmet Cevdet ÇELENLİGİL; Şengil, NevsanPublication A New Bat Optimization Algorithm to Solve EPD Problem Solving with Transmission Loss(2020) Javad RAHEBI MOHAMMED AL-JUMAILI; Altınbaş Üniversitesi, Elektrik ve Elektronik Mühendisliği Bölümü, İstanbul, Türkiye Türk Hava Kurumu Üniversitesi, Elektrik Elektronik Mühendisliği Bölümü, Ankara, TürkiyeWhile, researchers work to make the systems operate economically and reduce operational cost, in this study, we work to reduce the fuel costs to make the power station running economically as much as possible by utilizing the Economic Power Dispatch (EPD) and the optimization algorithms. The economic power dispatch (EPD) is an integral part of the power system, The major roles and the purpose of its use are for achieving a reliable and efficient operation out of power system generation networks, and this operation should be obtained by minimizing the generator fuel cost. Getting optimal solutions to EPD problem requires efficient optimization algorithms. Novel Bat Algorithm (NBA) is one of the most recent methods and it has already proven its efficiency and reliability for solving the EPD problem. This paper proposes Novel Bat Algorithm (NBA) in order to solve the EPD problem based on the large scale power system. The NBA has proved its efficiency and it gave a perfect performance for small-scale systems compared with the original Bat algorithm (BA), because of considering the Doppler Effect and assumed that bat can move between various habitats. The study of the EPD for large-scale power systems is more important than study it for small ones, because all power systems in countries are considered large networks. This is why all modern studies focus on the study of EPD for large systems. To test the performance of NBA during small and large scale power system, we have applied it to many systems, including 3-thermal units, 6-thermal units, 31-Iraqi thermal units and IEEE 40-thermal units respectively, with transmission losses and generator limits, and we have made a comparison of the obtained results of NBA with other optimization methods. The Iraqi thermal units have been utilized as a new data.Publication A novel hybrid teaching-learning-based optimization algorithm for the classification of data by using extreme learning machines(2019) Ender SEVİNÇ Tansel DÖKEROĞLU; Türk Hava Kurumu Üniversitesi TED ÜniversitesiData classification is the process of organizing data by relevant categories. In this way, the data can beunderstood and used more efficiently by scientists. Numerous studies have been proposed in the literature for the problem of data classification. However, with recently introduced metaheuristics, it has continued to be riveting to revisit this classical problem and investigate the efficiency of new techniques. Teaching-learning-based optimization (TLBO) is a recent metaheuristic that has been reported to be very effective for combinatorial optimization problems. In this study, we propose a novel hybrid TLBO algorithm with extreme learning machines (ELM) for the solution of data classification problems. The proposed algorithm (TLBO-ELM) is tested on a set of UCI benchmark datasets. The performance of TLBO-ELM is observed to be competitive for both binary and multiclass data classification problems compared with state-of-the-art algorithms.Publication A numerical study on influence of strain gradientson lattice rotation in micro-machining of a single crystal(2021) Murat DEMİRAL Anish ROY Vadim V. SILBERSCHMIDT; Türk Hava Kurumu Üniversitesi, Makina Mühendisliği Bölümü, Ankara, Türkiye Loughborough Üniversitesi, Wolfson Makine, Elektrik ve İmalat Mühendisliği Okulu, Birleşik Krallık Loughborough Üniversitesi, Wolfson Makine, Elektrik ve İmalat Mühendisliği Okulu, Birleşik KrallıkIn latest years small scale machining has been widely used in advanced engineeringapplications such as medical and optical devices, micro- and nano-electro-mechani cal systems. In micromachining of metals, a depth of cut becomes usually smallerthan an average crystal size of a polycrystalline structure; thus, the cutting processzone can be localized fully indoors of a single grain. Due to the crystallographic ani sotropy, development of small scale machining models accounting for crystal plastic ity are essential for a precise calculation of material removal under such circum stances. For this purpose, a 3D finite-element model of micro-cutting of a single grainwas developed. A crystal-plasticity theory accounting for gradients of strain, imple mented in ABAQUS/Explicit via a user-defined material subroutine VUMAT, was usedin the computations. The deformation-induced lattice rotations in micro-cutting of asingle crystal were analyzed extensively.Publication A Vibrational Spectroscopic Investigation of 2,2'-Bithiophene Using Experimental and DFT Methods(2023) Ebru KARAKAŞ SARIKAYA Ömer DERELİ Semiha BAHÇELİ Feride Pınar ÖZTURAN; Necmettin Erbakan Üniversitesi, Mühendislik Fakültesi, Temel Bilimler Bölümü, Konya, Türkiye Necmettin Erbakan Üniversitesi, Ahmet Keleşoğlu Eğitim Fakültesi, Fizik Bölümü, Konya, Türkiye Türk Hava Kurumu Üniversitesi, Havacılık ve Uzay Bilimleri Fakültesi, Uzay Mühendisliği Bölümü, Ankara, Türkiye Necmettin Erbakan Üniversitesi, Fen Bilimleri Enstitüsü, Nanobilim ve Nanomühendislik Anabilim Dalı, Konya, TürkiyeOrganic compounds like 2,2’-Bithiophene (with a synonym. 2,2'-bithienyl, 2,2'-dithienyl)-containing bis(dioxaborin) have drawn significant concern in the area of materials science because of their electron affinity and luminescent properties. With this motivation, we have been concentrating on the properties and functions of 2,2'-Bithiophene. The vibrational frequencies of the molecule 2,2'-Bithiophene in the solid phase were recorded using the Fourier Transformed-Infrared (FT-IR) and FT-Raman spectrometers. Meanwhile, the molecular geometric parameters, the spectral wavenumbers, HOMO-LUMO analysis and the molecular electrostatic potential (MEP) of the 2,2'-Bithiophene molecule were computed at the B3LYP/ 6-311++G (d,p) level of the theory. Furthermore, a comparison between experimental and calculated values for the vibrational frequencies of the 2,2'-Bithiophene molecule exhibits a good agreement.Publication Aerodynamic Performance Losses due to Ice Formation on the UAV’s Wings(2020) Özcan YIRTICI Durmuş Sinan KÖRPE Serkan ÖZGEN; Osmaniye Korkut Ata Üniversitesi, Osmaniye, Türkiye Türk Hava Kurumu Üniversitesi, Ankara, Türkiye Orta Doğu Teknik Üniversitesi, Ankara, TürkiyeIce accretion on unmanned air vehicle’s wing modifies the initial airfoilcontour and changes the aerodynamic characteristic of the wing. The aimof this research is to calculate performance losses on a wing due to theaccretion of rime ice. In this study, ice formation on NREL S826 airfoil ispredicted by using ice accretion tool. The computed aerodynamic loads arecompared for clean wings and iced wings with different aspect ratios. Thecomputations are based on the lifting-line method. According to the results,predicted aerodynamic performance loss is higher for small aspect ratiothan that of the bigger for the rime ice.Publication Aircraft Selection Decision Support Model for Fleet Planning of the Low Cost Airlines(Eskisehir Osmangazi University Journal of Economics and Administrative Sciences, 2023-08-01) Cem GÜNTUT; Meriç GÖKDALAY; Gökdalay, Meriç HaticeIn this study, a decision support model was created for the aircraft type selection in the fleet planning decision of a low-cost airline and 21 sub criteria were determined for the model in five main groups as technical, economic, environmental, political and other criteria. In this decision support model, the Fuzzy TOPSIS and Fuzzy MOORA Multi Criteria Decision methods were applied, and 17 different narrow body aircraft types produced by Airbus, Boeing, Embraer, and Airbus/Bombardier aircraft manufacturers were evaluated. In the evaluation, it was found that Airbus A321NEO was the most preferable aircraft for the low-cost airline business model among the aircraft types.Publication Airport terminal flow simulation: impact analysis of self-service check-in technologies usage past and during the Covid-19 pandemic(2022) Niyazi Cem GÜRSOY SAVAŞ SELAHATTİN ATEŞ; Türk Hava Kurumu Üniversitesi, Hava Ulaştırma Fakültesi, Pilotaj Bölümü, Ankara, Türkiye Eskişehir Teknik Üniversitesi, Ulaştırma Meslek Yüksekokulu, Havacılık İşletmeciliği Bölümü, Eskişehir, TürkiyeCheck-in is the process that passengers wait for the most before their flight. Waiting times of passengers will vary depending on the number of counters at the airport, the number of self-service facilities, and whether passengers benefit from online/mobile check-in technologies. As a result of the measures taken at airports with the Covid-19 pandemic, check-in processing times have been prolonged. In this study, Esenboğa airport domestic departure check-in operations are simulated with the ARENA-TRIAL simulation program. The developed scenarios were simulated at peak hours. Initially, it was determined that the number of employees and facilities should be increased to keep the service level at standards during the Covid-19 pandemic thanks to the optimum number of facilities obtained. Secondly, it was determined that the time spent by passengers for check-in processes increased significantly during the Covid-19 pandemic. In addition, it has been observed that the placement of the optimum number of self-bag drop facilities at the airport reduced the average waiting time required for the check-in processes of passengers in the period before and during Covid 19. Finally, during the Covid-19 pandemic, the airport queue density has increased dramatically.Publication Alkalin Fosfataz Benzeri Peptit Nanokatalizörler(2014) Mustafa Özgür GÜLER Emine Deniz TEKİN Ayşe Begüm TEKİNAY; Bilkent Üniversitesi, Malzeme Bilimi ve Nanoteknoloji Enstitüsü, Ankara, Türkiye Türk Hava Kurumu Üniversitesi, Hava Ulaştırma Fakültesi, Pilotaj Bölümü Bilkent Üniversitesi, Ulusal Nanoteknoloji Araştırma Merkezi, Ankara, TürkiyeEnzimler, reaksiyonların gerçekleşmesi için gerekli aktivasyon enerjisini düşürmeleri sebebiyle yaşam bilimlerinde önemli bir yere sahiptir. Bu özellikleri sayesinde reaksiyonların hızı milyonlarca ya da milyarlarca kat artabilmektedir. Reaksiyon hızını arttırmalarının yanı sıra, seçici reaksiyon gerçekleştirme özelliğine de sahiptirlerdir. Böylece sentez sonrası ürünlerin ayrılması gibi fazladan işlemlere gerek kalmadan daha az maliyetli reaksiyonlar gerçekleştirilebilmektedir. Günümüzde bilinen enzimlerin yaklaşık üçte birini metallerle koordine olan enzimler oluşturmaktadır. Bu tip enzimler, solunum, fotosentez, azot fikslenmesi, hidroliz kimyası gibi biyolojik sistemlerde hayati önem taşıyan mekanizmaların gerçekleşmesinde görev almaktadır. Metal iyonları, bir ya da daha fazla parçayla koordine olarak yapısal, katalitik ve elektron transferi gibi görevleri üstlenmektedir. Alkalin fosfataz (ALP) enzimi, nükleotitler ve alkaloidler gibi moleküllerdeki fosfat grubunun hidrolizinde görev alan bir enzimdir. Bu enzimin çinko varlığında aktivitesinin arttığı in vitro ve in vivo çalışmalarda gözlemlenmiştir. Bu enzim, aynı zamanda biyomineralizasyon için gerekli olan fosfat üretimine yardımcı olduğundan kemik dokuda yer alan hidroksiapatit üretimini hızlandırır. Bu projede, ALP aktivitesini taklit edebilen peptit nanofiber sistemleri geliştirilmiştir. Kendiliğinden düzenlenerek nonkovalent etkileşimler sayesinde multivalent aktif yüzey oluşturan peptit molekülleri, ALP’nin aktif bölgesindekine benzer şekilde çinkoya bağlanan amino asitler ile aktifleştirilerek hidroksiapatit üretilmesini sağlamıştır. Peptit nanosistemlerinin kararlılığı, hem hidrofilik hem de hidrofobik kısımlardan oluşmasından ileri gelmektedir. Hidrofobik kısma eklenen, beta yaprak oluşturma özelliğine sahip amino asitler sayesinde üç boyutlu bir yapı oluşturulabilmektedir. Bu özelliğe sahip amino asit dizininden sonra da, istenilen fonksiyona sahip amino asitler eklenebilmektedir. Bu projede, aynı stratejiyi kullanarak farklı yapısal özellikteki peptit moleküllerinin sentezlenmesi ve bu yapısal özelliklerin katalitik aktiviteye etkisinin araştırılması amaçlanmıştır. Böylelikle, yapay enzim yapımına, nanosistemlerle çözüm adımları ileri vadede sağlanacaktır. Sentezlenen yeni peptit nanoyapıların katalitik aktivitelerinin, canlı organizmalar üzerindeki etkisi de hücre üzerinde yapılacak in vitro deneyler ile gösterilmiştir. Ayrıca, sentezlenen yeni peptitler ve bu peptitlerin metal iyonlarıyla koordinasyonu sonucu oluşan üç boyutlu yapıların modellemeleri de desteklenmiştir. Bu tür teorik çalışmalar, sonraki supramoleküler yapıların tasarımında örnek teşkil edecektir.Publication An Analysis of the Impact of the Syrian Crisis on Turkey’s Politic-Military, Social and Economic Security(2020) Sertif DEMİR Muzaffer ERCAN; Türk Hava Kurumu Üniversitesi, İşletme Fakültesi, Ankara, Türkiye Bursa Uludağ Üniversitesi, İktisadi ve İdari Bilimler Fakültesi, Uluslararası İlişkiler Bölümü, Bursa, TürkiyeThis study analyzes how the ongoing Syrian Crisis has affected Turkey’s security. It starts with an overview of recent developments in the Middle East in general and in Syria specifically. It then examines the political, military, social, and economic effects of the Syrian Crisis for Turkey’s security. It concludes that the Syrian Crisis represents Turkey’s most challenging security problem since the end of the Second World War as it has had many profound impacts on the country.Publication An Application of an (R, S) Inventory Management Model for a Construction Materials Manufacturing Company by Using Simulation(2023) Durdu Hakan UTKU; Türk Hava Kurumu Üniversitesi, Endüstri Mühendisliği Bölümü, Ankara, TürkiyeGlobalization has motivated companies to develop competitive strategies in today's business environment. In this context, they lead them to review their costs. When the cost items are analyzed, the most critical point that will give an advantage to companies in terms of cost is that companies healthily manage their inventory. Inventory management is of vital importance as the companies have a significant percentage in terms of cost and ensure that the customer demands are met in a timely and sufficient manner. This study focuses on the problems of the company's inventory control decisions that ensure balanced and minimum costs through effective inventory management. In this study, one-year data on demand, consumption, and inventory of a company that uses traditional methods including semi-finished products are considered. Since the demand is not known precisely and it is probabilistic, we apply the (R, S) inventory control model. We use simulation as a stochastic methodology to determine the inventory level of the construction company under consideration. As a result of the study, after comparing the actual data in the current system with the developed model we apply, it is observed that the cost reduction and its use provided additional benefits to the company.Publication An Application: A Model with Sequence Dependent Setup Times for Parallel Machines for the Die House Station in a White Goods Manufacturing Company(2021) Selin KASIMOĞLU Gülce DEMİR Berrak Pınar YAZ Durdu Hakan UTKU; Türk Hava Kurumu Üniversitesi, Mühendislik Fakültesi, Endüstri Mühendisliği Bölümü, Ankara, Türkiye Türk Hava Kurumu Üniversitesi, Mühendislik Fakültesi, Endüstri Mühendisliği Bölümü, Ankara, Türkiye Türk Hava Kurumu Üniversitesi, Mühendislik Fakültesi, Endüstri Mühendisliği Bölümü, Ankara, Türkiye Türk Hava Kurumu Üniversitesi, Mühendislik Fakültesi, Endüstri Mühendisliği Bölümü, Ankara, TürkiyeExcessive buffer inventory may disrupt production and constitute one of the mainproblems. One of the ways of coping with the inventory problems in the massproduction lines is to achieve and implement a detailed production schedule. Inthis study, a company with a mass production line in the die house station of awhite goods sector is in consideration. A mixed-integer programming model withsequence-dependent setup times has been developed to solve the excessive work inprocess problems for the dye house station. The developed model has been appliedto the company to test the model by using real data and the problem has beensolved by using the General Algebraic Modeling System (GAMS) CPLEX 24,1solver. The optimal solution is obtained in 10 hours and 3 minutes. In the solution,the total earliness and tardiness time for 30 jobs is 4299 minutes.Publication An Approach to Customer Lifetime Value Modeling for Service Firms1(2017) Hüseyin Erbil ÖZYÖRÜK Bahtışen KAVAK; Öğr. Gör. Dr., Türk Hava Kurumu Üniversitesi İşletme Fakültesi, Prof. Dr., Hacettepe Üniversitesi İşletme Fakültesi,Bu çalışmada, müşteri yaşam boyu değerinin hesaplanmasına ilişkin bir yaklaşım geliştirilmeye çalışılmış ve bu bağlamda bireysel marka değiştirme matrisleri oluşturulmuştur. Model hizmet firmalarına yönelik olup havayolu sektörü çalışmanın uygulama alanı olarak seçilmiştir. Pazarlama karması kullanılarak bireysel marka değiştirme matrislerinin oluşturulabilmesi için, havayolu sektörünün pazarlama karmasını oluşturan bileşenler belirlenmeye çalışılmıştır. Çalışmada ortaya konan fayda fonksiyonuna göre, pazarlama karmasının "dağıtım" öğesinin uçuş rotası ve internet üzerinden bilet satışı bileşenleri ile "tutundurma" öğesinin marka imajı bileşeninin müşteri faydasına olan katkılarının diğer bileşenlerden fazla olduğu görülmüştürPublication An Economic Analysis on the Use of Resources Allocated for Defense: An Empirical Study on Turkey(2023) Ceyda AKTAN Yaşar KÖSE Emre YILMAZ; Türk Hava Kurumu Üniversitesi, Ankara, Türkiye Türk Hava Kurumu Üniversitesi, Ankara, Türkiye Türk Hava Kurumu Üniversitesi, Ankara, TürkiyeIn this study, the relationship between Turkey's defense expenditures and the independent variables selected as gross domestic product, foreign debt, and unemployment, in a 33-year period between 1998 and 2020, were examined using the Toda-Yamamoto causality test. According to the findings, it has been observed that there is causality from defense expenditures to gross domestic product, that is, the change in defense expenditures affects gross domestic product. Similarly, causality has been determined from defense expenditures to external debt. Therefore, it is possible to state that the change in defense expenditures will have an impact on foreign debt. In this respect, the findings are in agreement with the literature. The increase in defense expenditures will increase the production of the defense industry, the export of this production will result in a resource inflow to the country and the gross domestic product will increase. On the other hand, in some countries, defense expenditures will be financed by debt from foreign sources, which will increase foreign debt.Publication An Empirical Research on The Factors Affecting Profitability in Air Transportation(2023) Emre YILMAZ Yaşar KÖSE; THK Üniversitesi, Ankara, Türkiye THK Üniversitesi, Ankara, TürkiyeThis study aims to analyse the impact of traditional airline companies' internal and external environmental factors on profitability. In total, 17 airlines operating in different regions were included in the study. Passenger load factor, cargo ton-km and the number of destinations were chosen as internal factors affecting the profitability of airlines. GDP, oil prices and exchange rate figures were external environmental factors affecting profitability. Panel ARDL analysis method was used in the study. In the model of the study, all variables were analysed together without division. All selected variables have been observed to affect airline profitability, and the effect of external environmental factors on profitability is more significant.Publication AN ERGONOMIC CLASSROOM DESIGN APPLICATION at a UNIVERSITY in TURKEY(2021) Durdu Hakan UTKU Gürkan Güven GÜNER Göktuğ ALTUĞ Anıl GÜNEY; Türk Hava Kurumu Üniversitesi, Endüstri Mühendisliği Bölümü, Ankara, Türkiye Türk Hava Kurumu Üniversitesi, Endüstri Mühendisliği Bölümü, Ankara, Türkiye Türk Hava Kurumu Üniversitesi, Endüstri Mühendisliği Bölümü, Ankara, Türkiye Türk Hava Kurumu Üniversitesi, Endüstri Mühendisliği Bölümü, Ankara, TürkiyePurpose: Ergonomics is a branch of science that uses scientific methods to improve the workplaces and environments to maximize the comfort and safety of humans. In this study, we suggest new classroom furniture dimensions defining the problems about environmental factors in the classrooms such as noise, light, air conditioning, or temperature by considering the real data obtained from a university. Methodology: A questionnaire is prepared to determine the most complained problems by the students about the classroom furniture and environment. A total of 219 students participate in the questionnaire at a university in Ankara, Turkey. The dissatisfaction scores are evaluated for each question to define the most complained problems. Findings: The results show that most of the students are not satisfied with the use of tablet-armed chairs due to different reasons. To solve the problems, the anthropometric measurements of the students are evaluated. Based on these measurements, new furniture dimensions are suggested and compared with the existing ones. Originality: The ergonomic classroom design in this study is an original work that is designed according to the data obtained from the university in concern. It is aimed that the implemented methodology and the comprehensive literature review for the ergonomic classroom design in this study can be a source of inspiration for the educational institutions.Publication An Inventory Optimization Model for a Textile Manufacturing Company(2022) Adem PINAR Durdu Hakan UTKU Fatih Kasimoglu; Türk Hava Kurumu Üniversitesi, İşletme Fakültesi, Lojistik Yönetimi Bölümü, Ankara, Türkiye Türk Hava Kurumu Üniversitesi, Mühendislik Fakültesi, Endüstri Mühendisliği Bölümü, Ankara, Türkiye Türk Hava Kurumu Üniversitesi, Mühendislik Fakültesi, Endüstri Mühendisliği Bölümü, Ankara, TürkiyeInventory management is a crucial issue in most businesses from factories in industry to small and large organizations in the production or service sector. A company should determine an optimum inventory level between excessive inventory that takes up physical space, costs much, and lack of inventory which disrupts the supply chain causing unavailability of the product that makes customers change their idea and buy from another supplier. In this study, we first classify the items that the company manufactures by using ABC analysis and develop a mathematical model to minimize total cost to enable a better inventory management. We use ABC analysis method to evaluate products in a textile company in terms of importance and to track these products according to their priorities. Accordingly, we propose a mixed integer programming model to determine production quantities and inventory levels with minimum cost. The results shows that the company in concern can improve its total production and inventory costs by 3.8 percent.