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Item 10. KALKINMA PLANI HEDEFLERİ VE NÜKLEER SANTRALLER(Bilim ve Teknoloji, 2013-09-06) BALKU, ŞaziyeTürkiye Cumhuriyeti 10. Beş Yıllık Kalkınma Planı (2014-2018) resmi hazırlık süreci 5 Haziran 2012 tarihli 14 sayılı Başbakanlık Genelgesiyle başlatılmış ve kurulan Özel İhtisas Komisyonları arasında Enerji Güvenliği ve Verimliliği de yer almıştır. Komisyonu oluşturan akademisyenler, kamu kurum ve kuruluşları ile özel sektör ve sivil toplum kuruluşlarının temsilcileri enerji arz güvenliği, fiyatlarının yüksekliği ve belirsizliği, çevresel sorunlar, iklim değişikliği, yüksek yatırımda finansman ihtiyacı, enerjinin verimsiz kullanılması, dışa bağımlılığı gibi temel sorunlar ve gelişmeler göz önünde tutularak, ülkemiz enerji sektörü için durum analizi yapmak, bir vizyon geliştirmek ve yol haritası oluşturmak üzere çalışmalarını sürdürmüşler ve mevcut durumun değerlendirmesi, sektördeki gelişme eğilimleri ve muhtemel yansımaları, geleceğe dönük beklentiler, güçlü ve zayıf taraflar, fırsatlar-tehditler, sorunlar ve çözüm önerileri, politika ve strateji önerileri ile plana katkıda bulunmuşlardır.Item A CALCULATION METHOD FOR A SHOVEL-TRUCK SYSTEM WITH AN INCLINED HOIST OF TRUCKLIFT TYPE(The International Journal of Mineral Resources Engineering, 2008-07-21) CZAPLICKI, Jacek M.The proposal to apply an inclined hoist of the Trucklift type in open pit mining hung in mid-air. Although this suggestion is quite interesting, no mine around the world was interested in such an installation. It appears that one of the main reasons for which the proposal missed its aim was the lack of the method of analysis and calculation of shovel-truck systems including such a type of hoist to allow an assessment of what kind of improvement might be expected if the hoist is employed in the system. This paper shows the method of analysis and calculation of shovel-truck systems with a hoist, considering the majority of the important compenents that have an influence on the course of the operation/exploitation process of the machinery system. An example is given to add to the communicativeness of the considerations and conclusions drawn.Article A Close Examination of Ankara’s Reinforced Concrete Buildings Designed and Constructed between 1923 and 1938(Buildings, 2023-01) Tunç, Gökhan; Tunç, Tanfer EminThe Republic of Turkey was established in 1923 out of the remains of the Ottoman Empire. Between 1923 and 1938, the Turkish republic underwent fifteen years of rapid expansion and growth, with Ankara as its new capital and Mustafa Kemal Atatürk (1881–1938) as its first president. During this period, reinforced concrete (RC) played a significant role in the construction of Ankara’s public-use buildings. This study focuses on 57 of these structures, built either partially, or entirely, out of RC. The buildings are classified with respect to their duration, soil properties, foundation types, structural design details, construction types, materials and overall costs. In order to provide a better picture of the time period in which these buildings were designed and constructed, the technical, financial and political aspects of the projects, and the difficulties and challenges involved in their design and construction, are also discussed. Furthermore, this study outlines the impact of foreign engineers, construction workers, firms and the educational system on the development of civil engineering and use of RC in Turkey.Item A COMPANY-PERSPECTIVE COST ANALYSIS OF THE PERSONAL DUST MONITOR (PDM)(The International Journal of Mineral Resources Engineering, 2007-07-20) REED, W.R.; VOLKWEIN, J.C.; JOY, G.J.The personal dust monitor (PDM) is a new coal mine respirable dust sampling instrument that has the ability to provide accurate end-of-shift and real-time respirable dust exposure data. A hypothetical cost comparison analysis of the PDM with the current MSHA-required coal mine dust personal sampling unit (CMDPSU) was conducted. Some simplifying assumptions were made to create hypothetical cases for analysis. This analysis was limited to respirable dust sampling of the one designated operator (DO) and one designated area (DA) for one mechanized mining unit (MMU) which operated one shift per day. Only sampling intervals of the minimum sampling as required by federal regulations and continuous sampling were analyzed. This cost analysis from the company perspective is only one part of an overall cost/benefit analysis that should be conducted at a later date. In this analysis, company-associated costs were examined for both sampling systems. Results show that the PDM, while it has high initial costs of approximately $ 12,600, may be a cost-effective sampling system for measuring coal mine respirable dust. The estimated present worth cost of conducting the minimum requried dust sampling over a five-year life ranges from $5,850 to $19,000 for the CMDPSU, with the higher present worth cost including costs of potential violations incurred. For the PDM, the comparable present worth cost is $14,900 to $19,300, with the lower present worth cost representing a lower capital cost of $8,150 per unit if more than 850 units are produced per year, while the higher present worth cost reflects the results with the higher $12,600 capital cost.Article A Comparative Analysis of the Criteria for Choosing Sustainable Materials for Façades in Turkey and the European Union(Sustainability, 2024-02-11) Daşkın, Haney Başak; Bărbulescu, Alina; Muntean, Radu; Akçay, Emre CanerOne of the primary contributors to energy consumption is the construction industry. To address the urgent demand for eco-friendly approaches in this field, this study conducted an investigation on Scopus and Web of Science databases to identify the criteria for selecting sustainable materials for façades. Three groups of criteria were derived after a systematic review: Environmental, Social/economic and Technical. The main goal of the research was to answer the question of whether there are differences in these materials’ selection between Turkey and European Union countries. After applying statistical tests, it was found that there are significant differences in selecting eco-friendly material only from the social/economic perspective. The most important sub-criterion is the economic cost. Comparisons with results from China and US confirm this finding.Item A Comprehensive Assessment Plan for Accreditation in Engineering Education: A Case Study in Turkey(International Journal of Engineering Education, 2015-08-02) TURHAN, Çiğdem; ŞENGÜL, Gökhan; KOYUNCU, MuratThis paper describes the procedure followed by Computer Engineering and Software Engineering programs at Atilim University, Ankara, Turkey, which led to the granting of five years of accreditation by MUDEK, the local accreditation body authorized by The European Network for Accreditation of Engineering Education (ENAEE) to award the EUR ACE label, and a full member signatory ofWashington Accord of International Engineering Alliance (IEA). It explains the organizational structure established for preparation, determination and measurement of the educational objectives, program outcomes, course outcomes, and the continuous improvement cycle carried out during the preparation period. The aim of the paper is to share methods and experiences which may be beneficial for the other programs that are intended for accreditation.Article A comprehensive characterization of the effect of spatter powder on IN939 parts fabricated by laser powder bed fusion(Materials and Design, 2023-10-15) Doğu, Merve Nur; Özer, Seren; Mussatto, Andre; Yalçın, Mustafa Alp; Davut, Kemal; Obeidi, Muhannad Ahmed; Kumar, Ajay; Hudson, Sarah; O'Neill, Darragh; O'Connor, Robert; Gu, Hengfeng; Brabazon, DermotThis study is focused on a comprehensive characterization of virgin and spatter IN939 powders and the effects of a certain amount of spatter powder on the part quality of IN939 fabricated by the L-PBF process. A brown tint coloration formed Al2O3 oxide, pores, a 124.4% increase in the average particle size, a 10.2% decrease in the powder circularity, and a 7.5% decrease in the powder aspect ratio were observed in the spatter powder. Additionally, higher average grain size and lower nanohardness were obtained for the spatter powder. In order to understand the effect of a certain amount of spatter powder on the part quality, 10 wt.% spatter powder was mixed with the virgin powder. This addition was found to decrease the flowability of the powder. Moreover, this addition decreased relative density by around 0.3% and increased surface roughness by around 80.8% in the fabricated samples (termed as V and SV). On the other hand, there was no considerable microstructural, texture, microhardness, and nanohardness difference between V and SV samples, although the spatter powder addition caused a 30.2% increase in the average grain size of SV. The overall texture for both V and SV samples exhibit (001)//BD.Item A computational study on 4,7-di(furan-2-yl)benzo[c][1,2,5] thiadiazole monomer and its oligomers(Journal of Molecular Modeling, 2014-04-23) KAYI, HakanThe energy gap, Eg, between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molec ular orbital (LUMO) energy levels that determines the elec tronic and optical properties of 4,7-di(furan-2- yl)benzo[c][1,2,5]thiadiazole (FSF) polymer is calculated by performing quantum chemical calculations. First, we theoret ically investigated the most stable conformers of FSF mono mer and its corresponding oligomers at the B3LYP/6-31G(d) and B3LYP/LANL2DZ levels of theory. We reveal the theoret ical molecular structure of this very recently synthesized novel monomer and its oligomers for the first time in the literature. Our results from the B3LYP/6-31G(d) calculations indicated that FSF polymer has a low HOMO-LUMO gap of 1.55 eV to be in good agreement with the experiments. Experimental design and synthesis of novel conjugated polymers require time-consuming and expensive procedures. The findings from this study are promising for the use of computational methods in the design of the novel conjugated polymers, and help to narrow the materials to be used in design and synthesis of conjugated polymers with desired properties.Item A Concept Map Approach for Introduction to Computer Engineering Course Curriculum(IEEE EDUCON Education Engineering 2010, 2010-04-16) TOKDEMİR, Gül; ÇAĞILTAY, NergizAs in any discipline, in Computer Engineering, students start learning the basic concepts of the discipline in their first year through an Introduction to Computer Engineering course. The topics toughed in this course can be grouped into two. The first group includes simple concepts like binary numbering system, hard disk, memory, and I/O devices. In the second group, and introduction to the courses that they will take in the next semesters of the program which includes programming, networking, software engineering, artificial intelligence and database systems. The main objective of this course is to give an introduction about the general concepts of the field to the first year Computer Engineering students and prepare them to understand the connections between them for their future studies. However, students and instructors face with many problems in this course. First, because of the diversity of the concepts given in the course, it is very diffucult for the students to see the big picture of the Computer Engineering domain. Similarly, it is diffucult for the instructors to prepare the course content in an integrated manner at the students' level. Additionally, the perception of the theory and practice behind the hardware and software topics and their connections is not an easy task for the beginners. Moreover, the topics are mostly abstract topics, which do not allow application of any laboratory sessions. Students usually find this course diffucult to understand, which decreases their motivation about the department and success of the course. This study is established to propose a concept map approach to better visualize and discover all the connections between the concepts of Computer Engineering field which can be used in the curriculum of the programs and introductory courses of the field addressing the above problems. The proposed concept map helps to visualize the general picture of the field.Article A DFT study of TiC3 as anode material for Li-ion batteries(Applied Surface Science, 2023-07-13) Park, Jongee; Fatima, Syeda AfrinishTwo-dimensional monolayer titanium carbide (TiC3) was used to study as a suitable electrode material for lithium-ion batteries with first principles calculation. The monolayer TiC3 showed excellent structural stability, high mechanical stiffness and good electronic conductance behaviour. The adsorption of Li on the carbon rich composition of titanium carbide monolayer is predicted to be favourable. TiC3 structure has remained the same, preserving its metallicity after Li adsorption with attaining high electrical conductivity during lithiation/delithiation process. Especially, the theoretical specific capacity of TiC3 monolayer is high, up to 1916 mAh/g, which is five times higher than the practical graphite. The low open circuit voltage (0.26 V) and diffusion energy barrier (0.25 eV) are also beneficial for overall performance of LIBs. Importantly, during lithiation the change in area is very small and reaches only 8.1 % for full lithiation indicating that it can avoid the large volume expansion during charge/discharge cycles. Its excellent performance, including high melting temperature, dynamical and mechanical stability, can be credited to the rigidness of the TiC3. Given these advantages, that is, high specific capacity, low Li diffusion energy barrier, low open circuit voltage and high in-plane stiffness, TiC3 monolayer can be a promising anode material for lithium-ion batteries.Item A GENETIC ALGORITHM BASED COURSE SCHEDULING SYSTEM(Ulusal Bilişim Kurultayı, 2008-08-04) AYDIN, Cansu Çiğdem; ÇAĞILTAY, Nergiz; BİROĞUL, SerdarCourse scheduling problem is assigning of courses into specific time slots and located in suitable rooms. The manual solution of this problem by considering all constraints usually requires a long time and a hard work in order to provide an appropriate solution. In addition, the obtained solution usually is unsatisfactory due to limited human oversight. In this study, Genetic Algorithm (GA) is presented for solving the constraint-based university timetabling problem. The developed system includes flexible and intelligent software that automate the course scheduling task and addresses all special features found in Atilim University’s Engineering Faculty.Article A Hybrid-Flipped Classroom Approach: Students’ Perception and Performance Assessment(Ingeniería e Investigación, 2023-08-04) Yalçınkaya Gökdoğan, Bengisu; Çoruk, Remziye Büşra; Benzaghta, Mohamed; Kara, AliThis study presents an improved hybrid-flipped classroom (hybrid-FC) education method based on technology-enhanced learning (TEL) along with diluted classes for a course on probability and random processes in engineering. The proposed system was implemented with the participation of two student groups who alternated weekly between attending face-to-face activities and fully online classes as a sanitary measure during the pandemic. The education model was combined with the flipped classroom (FC) approach in order to improve the quality of learning and address the negative effects of remote education. Before the lessons, the students studied the course material, filled a question form, and then took a low-stake online quiz. Then, the students attended a session where the questions reported in the forms were discussed, and they took an online problem-solving session followed by an individual quiz. Class sessions were available to both online and face-to-face students, as well as in the form of video recordings for anyone who missed lessons. Qualitatively and quantitatively, the proposed education method proved to be more effective and comprehensive than conventional online methodologies. The students' performances were evaluated via quizzes and exams measuring the achievement of the course learning outcomes (CLOs). Weekly pre/post-tests were applied to examine the students’ progress in each topic. Midterm and final exams were planned to measure the level of success for all course topics. Additionally, the students' perception was assessed with questionnaires and face-to-face interviews. A performance assessment showed an apparent increase in the success rate, and the students' perception was found to be positive. Este estudio presenta un método educativo mejorado de aula invertida híbrida (hybrid-FC) basado en el aprendizaje mejorado por tecnología (TEL) junto con clases diluidas para un curso sobre probabilidad y procesos aleatorios. El sistema propuesto se implementó con la participación de dos grupos de estudiantes que alternaban semanalmente entre asistir a actividades presenciales y totalmente en línea como una medida sanitaria durante la pandemia. El modelo educativo se combinó con el enfoque de aula invertida (FC) para mejorar la calidad del aprendizaje y hacer frente a los efectos negativos de la educación a distancia. Antes de asistir a clase, los estudiantes estudiaban el material del curso, completaban un formulario de preguntas y luego tomaban un quiz en línea de bajo impacto. Luego, los estudiantes asistían a una sesión en la que se discutían las respuestas en los formularios, y tomaban una sesión en línea de resolución de problemas, seguida de un cuestionario individual. Las clases estaban disponibles tanto para los estudiantes en línea como para aquellos que asistían de forma presencial; también había grabaciones de video para quien faltara a clases. Cualitativa y cuantitativamente, el método educativo propuesto demostró ser más efectivo y completo que los métodos online convencionales. El desempeño de los estudiantes se evaluó mediante cuestionarios y exámenes que medían el logro de los resultados de aprendizaje del curso (CLO). Se realizaron exámenes previos y posteriores semanales para examinar el progreso de los estudiantes en cada tema. Se planificaron exámenes parciales y finales para medir el nivel de éxito de todos los temas del curso. Además, la percepción de los estudiantes se evaluó con cuestionarios y entrevistas presenciales. La evaluación del desempeño mostró un aumento aparente en la tasa de éxito, y se encontró que la opinión de los estudiantes era positiva.Item A Magnetic Measurement System and Identification Method for Buried Magnetic Materials Within Wet and Dry Soils(IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, 2016-03-04) EGE, Yavuz; NAZLIBİLEK, Sedat; KAKİLLİ, Adnan; ÇITAK, Hakan; KALENDER, Osman; ERTÜRK, Korhan Levent; ŞENGÜL, Gökhan; KARAÇOR, Deniz—In this paper, a new magnetic measurement system is developed to determine upper surfaces of buried magnetic materials, particularly land mines. This measurement system uses the magnetic-anomaly-detection method. It also has intelligent identification software based on an image matching algorithm. It is aimed to determine and identify the buried ferromagnetic materials with minimum energy consumption. It is concentrated on the detection and identification of the shapes of upper sur faces of buried magnetic materials in dry and wet conditions. The effect of humidity in the detection process for detection is tested. In this paper, we used sensor images to identify various ferromagnetic materials and similar objects. Sensor images of soils at various humidities covering the objects were obtained. We used the speeded-up-feature-transform algorithm in the comparison process of the images. Dry soil sample images match with the corresponding wet soil samples with the highest matching rate. The images for different objects can easily be distinguished by the matching process.Item A Mobile Application Flow Representation for Mutual Understanding of IT and Healthcare Professionals(2013-08-08) ERTURAN, Yusuf Nasuh; BİLGEN, Semih; TOKDEMİR, Gül; ÇAĞILTAY, Nergiz; YILDIZ, Ekrem; ÖZCEBE, EsraEver since mobile applications were developed and became popular, they have started to take part in almost every field of our lives. Healthcare is one of the most popular fields that mobile applications have become a part of. However, development of mobile healthcare applications requires an inter disciplinary work on which people from different domains should communi cate. To do so efficiently, mobile application instructions should be provided as clearly as possible so that mutual understanding can be achieved. This study, aims to provide a methodology to provide the common grounds for healthcare and IT specialists so that to improve the satisfaction level of all the stakeholders of the system from the provided IT services and the end-user interfaces. In other words, by providing a better communication medium for the stakeholders dur ing the design phase, we believe that software development process will be improved, so do their satisfaction from the developed system.Item A new extended δ-shock model with the consideration of shock magnitude(Applied Stochastic Models in Business and Industry, 2024-07-14) Lorvand, Hamed; Eryılmaz, SerkanIn this article, a new -shock model that takes into account the magnitude of shocks is introduced and studied from reliability perspective. According to the new model, the system breaks down if either a shock after non-critical shock occurs in a time length less than or a shock after a critical shock occurs in a time length less than where . The distribution of the system's lifetime is studied for both discrete and continuous intershock time distributions. It is shown that a new model is useful to describe a certain cold standby repairable system.Article A new generalized 𝜹-shock model and its application to 1-out-of-(m + 1):G cold standby system(Reliability Engineering and System Safety, 2023-02-28) Eryılmaz, Serkan; Ünlü, Kamil DemirberkAccording to the classical 𝜹-shock model, the system failure occurs upon the occurrence of a new shock that arrives in a time length less than 𝜹; a given positive value. In this paper, a new generalized version of the 𝜹-shock model is introduced. Under the proposed model, the system fails if there are m shocks that arrive in a time length less than 𝜹 after a previous shock, m 1. The mean time to failure of the system is approximated for both discretely and continuously distributed intershock time distributions. The usefulness of the model is also shown to study 1-out-of-(m + 1):G cold standby system. Illustrative numerical results are presented for geometric, exponential, discrete and continuous phase-type intershock time distributions.Article A new method to determine the continuous refractive index of an absorbing film by Generalized Stockwell Transform(Optics and Laser Technology, 2023-12) Coşkun, Emre; Emir, Cansu; Selamet, Semanur; Parlak, Mehmet; Özder, SerhatGeneralized Stockwell Transform (GST) was adapted to analyze a transmittance signal to continuously determine the refractive index and extinction coefficient. The process is built by analyzing oscillation frequencies of the transmission signal where oscillations exist. The simulation studies clearly show the advantage of the locally referenced phase property of the presented method. The validity of the method was checked for a CdS thin film. The results determined by the GST method are consistent with the results determined by envelope and other signal analyzing methods, and the literature. The noise and relative error analysis of the method was also discussed.Item A New RF and Microwave Engineering Course Enriched With Advanced Technologies(2010-02-08) AYDIN, Elif; ÇAĞILTAY, NergizIn this study, a curriculum model including recent developments and technologies in the Radio Frequency (RF) and Microwave Engineering field by using a blended approach is proposed. This study covers the description of the content of theoretical and hands on applications, the integration model of the technological tools into the proposed curriculum, and the instructional approaches used in the new course design. The main goal of the course is to prepare students for future professional careers in RF and Microwave Engineering by supporting them with new instructional technologies. The secondary goal of the course is to better prepare the students for the sequence of senior courses in the Electrical and Electronics Engineering program of Atilim University. The course is structured with a balance between theory and laboratory, including remote and in lab measurement experiments as well as modeling and designing microwave components by means of computer tools and design fabrication. The newly designed course is implemented at the Atilim University. The study also reports the first semester implementation.Article A novel comfort temperature determination model based on psychology of the participants for educational buildings in a temperate climate zone(Journal of Building Engineering, 2023-10-01) Özbey, Mehmet Furkan; Turhan, CihanMaintaining thermal comfort in the educational buildings is vital due to the impacts on learning effectiveness of students. Therefore, development of a proper comfort temperature in educational buildings is a must. In naturally ventilated and mixed-mode buildings, the adaptive thermal comfort model, which considers additively psychological, and behavioural factors to the Fanger's PMV/PPD model, is commonly applied based on regression analyses. However, the psychological adjustments based on current mood state are very limited in these adaptive thermal comfort models. Therefore, this study focuses on the psychological adjustments in terms of Profile of Mood States in order to predict comfort temperature of students in a case building. The experiments are conducted in a university on a temperate climate zone for a long period-data including both heating and cooling seasons. In this study, the comfort temperatures for each student are determined via Griffith method for the case building. Moreover, the current mood states of students are assessed utilizing the Profile of Mood States survey, which are collected via a developed mobile application. As a conclusion, the relation between the current mood state of the students and comfort temperature are statistically investigated. The results show that a Griffith constant are found as 0.332/K and mean annual comfort temperature is found as 21.32 °C in the case building. Additionally, a significant difference is found in the comfort temperatures among the students who have more, or fewer concerns than typically reported. The novelty of the study is to present a comfort temperature determination model which considers human psychology as a starter study in the literature.Article A Novel Data Encryption Method Using an Interlaced Chaotic Transform(Expert Systems with Applications, 2024-03-01) Gökçay, Erhan; Tora, HakanWe present a novel data encryption approach that utilizes a cascaded chaotic map application. The chaotic map used in both permutation and diffusion is Arnold’s Cat Map (ACM), where the transformation is periodic and the encrypted data can be recovered. The original format of ACM is a two-dimensional mapping, and therefore it is suitable to randomize the pixel locations in an image. Since the values of pixels stay intact during the transformation, the process cannot encrypt an image, and known-text attacks can be used to get back the transformation matrix. The proposed approach uses ACM to shuffle the positions and values of two-dimensional data in an interlaced and nested process. This combination extends the period of the transformation, which is significantly longer than the period of the initial transformation. Furthermore, the nested process's possible combinations vastly expand the key space. At the same time, the interlaced pixel and value transformation makes the encryption highly resistant to any known-text attacks. The encrypted data passes all random-data tests proposed by the National Institute of Standards and Technology. Any type of data, including ASCII text, can be encrypted so long as it can be rearranged into a two-dimensional format.