TR-Dizin İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://gcris.yasar.edu.tr/handle/123456789/11291
Browse
Browsing TR-Dizin İndeksli Yayınlar Koleksiyonu by Language "İngilizce"
Now showing 1 - 20 of 241
- Results Per Page
- Sort Options
Article -(2019) ahmet goncu; Tolga Umut Kuzubaş; Mehmet Oğuz KARAHANBu çalışmada mesken ve ticari doğal gaz tüketimini bir stokastik sıcaklık modelini temel alan doğal gaz talep tahmini ile birlikte tahmin eden bir yöntem öne sürülmektedir. Talep ve sıcaklık süreçleri ayrı ayrı modellenip doğal gaz tüketiminin sıcaklığa şartlı dağılımı türetilmektedir. Doğal tüketim ve yerel sıcaklık süreçleri İstanbul’un günlük doğal gaz tüketim ve sıcaklık verileri kullanılarak tahmin edilmiştir. İlk olarak doğal gaz tüketiminin şartlı dağılımı kullanılarak nokta tahmincilerinin güven aralıkları oluşturulmuştur. Sonrasında doğal gaz tüketimi Monte Carlo simülasyonları ile oluşturulan sıcaklık ve tüketim patikaları kullanılarak tahmin edilmiştir. Farklı modellerin tahmin performansları geriye dönük test yöntemiyle gerçek tüketim değerleriyle karşılaştırılmıştır. Ayrıca analitik çözüm kullanılarak doğal tüketimi ile sıcaklık türev ürünleri arasında bir ilişki ortaya konulmuştur. Bu ilişki doğal gaz tedarikçilerinin sıcaklık türevleri kullanarak talep risklerinden kısmen korunmasına imkan sağlamaktadır.Article -(2020) ahmet goncu; MEHMET OGUZ KARAHAN; Tolga Umut KuzubaşBu çalışmada mesken ve ticari doğal gaz tüketimini bir stokastik sıcaklık modelini temel alan doğal gaz talep tahmini ile birlikte tahmin eden bir yöntem öne sürülmektedir. Talep ve sıcaklık süreçleri ayrı ayrı modellenip doğal gaz tüketiminin sıcaklığa şartlı dağılımı türetilmektedir. Doğal tüketim ve yerel sıcaklık süreçleri İstanbul’un günlük doğal gaz tüketim ve sıcaklık verileri kullanılarak tahmin edilmiştir. İlk olarak doğal gaz tüketiminin şartlı dağılımı kullanılarak nokta tahmincilerinin güven aralıkları oluşturulmuştur. Sonrasında doğal gaz tüketimi Monte Carlo simülasyonları ile oluşturulan sıcaklık ve tüketim patikaları kullanılarak tahmin edilmiştir. Farklı modellerin tahmin performansları geriye dönük test yöntemiyle gerçek tüketim değerleriyle karşılaştırılmıştır. Ayrıca analitik çözüm kullanılarak doğal tüketimi ile sıcaklık türev ürünleri arasında bir ilişki ortaya konulmuştur. Bu ilişki doğal gaz tedarikçilerinin sıcaklık türevleri kullanarak talep risklerinden kısmen korunmasına imkan sağlamaktadır.Article -(2018) Knud Erik JørgensenBu makale kuramsal bilginin değerli olduğu varsayımına dayanmakla beraber böyle bir varsayımın kendiliğinden kabul edilmesi doğru değildir. Gerçekten de makalenin ilk hedefi kuramsal bilginin karşılaştırmalı üstünlüğünü incelemektir. İkincisi ise şu soruya cevap vermektir: eğer kuram inşa etmek üzerine yapılan 100 çalıştay bir farklılık yaratacak olursa bu farklılık tam olarak ne olacaktır? Nihayetinde Bollywood Hollywood’dan daha fazla film üretmesine rağmen film yapımında dünya pazarı Hollywood’un hâkimiyeti altındadır. Bu nedenle akademik pazarlar arasında yurtiçi ve küresel olarak bir ayrım yapılacak olursa birtakım yurtiçi ve bölgesel pazarlara yönelik yapılan kuram inşası yurtiçi ve bölgesel marketlerdeki ‘tüketim’ kalıplarını etkileyebilir ama dünya marketi için aynı şeyin olacağı kesin değildir. Buna ek olarak 100 çalıştaya olan görünürdeki gereklilik Uluslararası İlişkiler disiplininin Amerikan hegemonyası altında olduğu varsayımına dayanmaktadır ancak bu varsayım Amerikan hegemonyasının kurumsal anlamda bir gerçek olmaya devam ettiği ancak dünyanın geri kalanında takip edilen kuramsal modalar ve tartışmalara bakıldığında durumun böyle olmadığını gösteren ampirik araştırmalarla sarsılmıştır. Kısacası entelektüel küresel hegemonya büyük ölçüde bir kuruntudur. Son olarak makale 100 çalıştayın gerekli olabileceği ancak iki neden yüzünden zaman kaybına dönüşebileceğini tartışmaktadır. Geçmişteki dünyayı kuramlaştırmakta bir sorun bulunmamaktadır ancak çalıştaylar güncel sorunlara hitap etmeli ve gelecek odaklı olmalıdır. Ayrıca çalıştaylar disiplinin (tartışmaya açık) çekirdeğinin yeniden tanımlanmasına katkıda bulunmalıdır.Article Article Citation - WoS: 1A bibliometric analysis of extended reality research trends in communication studies written in English: Mapping the increasing adoption of extended reality technologies(Istanbul Univ, FAC Communication, 2024) Simge Uğurluer; Mert SEVEN; Seven, Mert; Ugurluer, Simgeİletişim teknolojilerinin gelişimiyle birlikte genişletilmiş gerçeklik teknolojisi ve uygulamaları etkileşimli dijital deneyimlere katkı sağlama potansiyelleri nedeniyle giderek daha çok tercih edilmektedir. Genişletilmiş gerçekliğin entegrasyonu nesneler hakkında bilgi sağlamanın yanı sıra sanal bir katman aracılığıyla zenginleştirilmiş ve çeşitli etkileşimleri içeren bir deneyim sunmaktadır. Bu çalışma İngilizce dilinde gerçekleştirilmiş iletişim çalışmalarında 1992 ile 2023 yılları arasında genişletilmiş gerçeklik (extended reality) teknolojisi konusunda Web of Science Science Citation Index Expanded (SCI-EXPANDED) Social Sciences Citation Index (SSCI) Emerging Sources Citation Index (ESCI) ve Arts & Humanities Citation Index (AHCI) dizinlerinde yayımlanmış çalışmaların nicel ve sistematik bir incelemesini sunmaktadır. Araştırma kapsamında WOS veri tabanında endekslenen dergilerde karma gerçeklik artırılmış gerçeklik sanal gerçeklik ve genişletilmiş gerçeklik kavramları ile ilgili çalışmalar taranmıştır. Yayım tipi dili açık erişim kategorisi ve konu filtreleri ile ulaşılan 209 yayın bibliyometrik analiz kapsamına dahil edilmiştir. Bibliyometrik araçlar genişletilmiş gerçeklik ve iletişim çalışmalarındaki eğilimleri belirlemek amacıyla temel araştırma konuları ve kümeleri alanlar arası dağılım ülkeler bazında üretkenlik ve iş birliği anahtar kelime ve alıntı ağı ve eşdizim ağlarını belirlemek için kullanılmıştır. Bulgular genişletilmiş gerçeklik araştırmalarının iletişim çalışmalarındaki evrimini anlamaya katkıda bulunmuş ve gelecekteki araştırma çabaları için temel oluşturmuştur.Article A Canonical 3-D P53 Network Model that Determines Cell Fate by Counting Pulses(2018) Gökhan Demirkıran; Güleser Kalaycı Demir; Cüneyt GÜZELİŞFrom a system theory perspective p53 network dynamics is interesting since it can exhibit three dynamical modes of p53 namely low-level equilibrium oscillation and high-level equilibrium. Each of these modes are associated with different cell fate outcomes: cell survival cell cycle arrest and apoptosis.The literature reveals that a high level (apoptosis) is seen only after ending the oscillation phase so called two-phase dynamics which provides thedecision of apoptosis depending on the oscillation duration. This paper proposes that a negative feedback can keep time by counting the pulses ofoscillation to take the decision of apoptosis or cell survival. P53DINP1 which is the mediator of this feedback is added as a variable to a 2-D oscillatormodel of the p53 network. The resulting canonical 3-D model successfully replicates the two-phase dynamics. That is it possesses temporary oscillatorybehavior in which first oscillations (first phase) and then high level state (second phase) are observed. By introducing a new variable to the core oscillatorin the p53 network this study demonstrates that p53 network can be considered a modular structure which consists of an oscillator and other variablesthat control this oscillator to contribute to cell fate determination.Article A comparative study of Black-Scholes equation(2009) REFET POLATIn this paper we analyzed Options and Black -Scholes Models for the valuing and pricing of commodities. In particular we examined the numerical solution techniques of American Option Problems. For the comparison of the results pertaining to different methods we used classical methods utilizing chronological order. Then we compared the results of these methods and tried to determine the most efficient method.Article A Comprehensive Evaluation of Yacht Charter Service Concept: Influence of Voyager-to-Voyager Interaction on Service Satisfaction(2021) Neslihan Paker; Osman GökThe study attempts to evaluate yacht charter service attributes considering the service quality customer satisfaction and loyalty three-leg framework. Besides visited destinations the service concept is enlarged with social servicescape dimensions of interaction quality and customer similarity for a holistic approach. A self-administered questionnaire was provided to 359 customers and the relationships in the research model were tested via structural equation modeling. The results showed that satisfaction depends on the interaction quality which is strongly related to the similarity between other customers as well as the quality of the service elements and the attractiveness of the visited destination. This study presents a pioneering research attempt focusing on the influence of customer-to-customer interaction and customer similarity on yacht charter services. Findings of the study provide a theoretical contribution highlighting the importance of customer-to-customer interaction for service appraisals of customers. Theoretical and practical implications for interaction-dominant services are discussed.Article A Comprehensive Review of Feature Selection and Feature Selection Stability in Machine Learning(2023) Mustafa Büyükkeçeci; mehmet okurFeature selection is a dimension reduction technique used to select features that are relevant to machine learning tasks. Reducing the dataset size by eliminating redundant and irrelevant features plays a pivotal role in increasing the performance of machine learning algorithms speeding up the learning process and building simple models. The apparent need for feature selection has aroused considerable interest amongst researchers and has caused feature selection to find a wide range of application domains including text mining pattern recognition cybersecurity bioinformatics and big data. As a result over the years a substantial amount of literature has been published on feature selection and a wide variety of feature selection methods have been proposed. The quality of feature selection algorithms is measured not only by evaluating the quality of the models built using the features they select or by the clustering tendencies of the features they select but also by their stability. Therefore this study focused on feature selection and feature selection stability. In the pages that follow general concepts and methods of feature selection feature selection stability stability measures and reasons and solutions for instability are discussed.Article A Different Approach to Nurse Scheduling Problem: Lagrangian Relaxation(2020) Yucel Ozturkoglu; Ozturkoglu, YucelThe problem of nurse scheduling is categorized in an Np-Hard complexity as it is inherently composed of many limitations and assumptions. As the number of nurses and the number of days increase finding the solution of the problem becomes quite difficult. Therefore this paper propose both an integer-programming model and a Lagrangian relaxation approach for solving nurse-scheduling problem. Numerical results show that while the developed mathematical model works on small-scale problems Lagrangian relaxation method finds better results for large scale scheduling problem with much smaller duality gap in a reasonable computational time.Article A GENETIC ALGORITHM TO SOLVE THE MULTIDIMENSIONAL KNAPSACK PROBLEM(2013) MURAT ERSEN BERBERLER; Urfat G. NURİYEV; Aslı GÜLERIn this paper The Multidimensional Knapsack Problem (MKP) which occurs in many different applications is studied and a genetic algorithm to solve the MKP is proposed. Unlike the technique of the classical genetic algorithm initial population is not randomly generated in the proposed algorithm thus the solution space is scanned more efficiently. Moreover the algorithm is written in C programming language and is tested on randomly generated instances. It is seen that the algorithm yields optimal solutions for all instances.Article A New Genetic Algorithm for the 0-1 Knapsack Problem(2016) MURAT ERSEN BERBERLER; Urfat G. NURİYEV; Aslı GÜLER; Berberler, Murat Ersen; Güler, Aslı; Nuriyev, Urfat G.In this paper the 0-1 Knapsack Problem (KP) which occurs in many different applications is studied and a new genetic algorithm to solve the KP is proposed. In our methodology n items are represented by n genes on a bit array that compactly stores the values 0 or 1. When calculating fitness values of items coefficients of items whose values are 1 in the bit array are summed. Roulette wheel method is used for choosing parents, in this way it is provided that strong individuals produce more children. Crossover is applied in such a way that roulette wheel is rotated on genes with the same index of parents that the dominant parent can transfer its genes to the child. Mutation is applied for randomly chosen 25% genes and this process is repeated for the number of individuals. The algorithm is written in C programming language and is tested on randomly generated instances. In order to find the optimal solutions of these problems a program that has been written by dynamic programming technique is used. It is seen that the algorithm yields optimal solutions for all instances.Article A new model for minimizing the electric vehicle battery capacity in electric\rtravelling salesman problem with time windows(Tubitak Scientific & Technological Research Council Turkey, 2021) Kazım Erdoğdu; KORHAN KARABULUT; Erdoğdu, Kazım; Karabulut, KorhanThe growing pollution in the environment and the negative shift in the global climate compel authorities\rto take action to protect the environment and human health. Transportation is one of the major contributors to this\renvironmental decay. The harmful gases released to the air by the vehicles using petroleum fuel increase each day. One\rof the solutions is to make a gradual transition to electric vehicles. A major part of manufacturing an electric vehicle\ris to produce an efficient electric motor and battery for it. Reducing the manufacturing and operating costs of these\rcomponents will result in reducing the overall costs of electric vehicles. In this study a new variant of the electric\rtravelling salesman problem with time windows (E-TSPTW) was proposed. The objective function of the problem is to\rminimize the required initial battery capacity of the electric vehicle. For this goal a new energy consumption model\rconsidering the load of the vehicle was proposed with three scenarios. The proposed model was solved with a hybrid\rsimulated annealing algorithm for all these scenarios. The performance of the proposed method was compared to the\rsolutions found by a mixed integer linear programming model. The experimental results on the benchmark instances\rshow that up to a 35% reduction in initial battery capacity hence reduction in its cost is possible.\rArticle A Novel Clustering-based Forecast Framework: The Clusters with Competing Configurations Approach(2023) Gökhan Demirkıran; Miray Alp; Alp, Miray; Demirkıran, GökhanAccurate aggregate (total) short-term load forecasting of Smart Homes (SHs) is essential in planning and management of power utilities. The baseline approach consists of simply designing and training predictors for the aggregated consumption data. Nevertheless better performance can be achieved by using a clustering-based forecasting strategy. In such strategy the SHs are grouped according to some metric and the forecast of each group's total consumption are summed to reach the forecast of aggregate consumption of all SHs. Although the idea is simple its implementation requires fine-detailed steps. This paper proposes a novel clustering-based aggregate-level forecast framework so called Clusters with Competing Configurations (CwCC) approach and then compares its performance to the baseline strategy namely Clusters with the Same Configurations (CwSC) approach. The Configurations in the name refers to the configurations of ARIMA Multi-Layer Perceptron (MLP) and Long Short-Term Memory (LSTM) forecasting methods which the CwCC approach uses. We test the CwCC approach on Smart Grid Smart City Dataset. The results show that better performance can be achieved using the CwCC approach for each of the three forecast methods and LSTM outperforms other methods in each scenario.Article Citation - WoS: 9Citation - Scopus: 9A novel square-root domain realization of first order all-pass filter(Tubitak Scientific & Technological Research Council Turkey, 2010) Sinem ÖLMEZ; Uğur ÇAM; Çam, Uğur; Ölmez, SinemIn this paper a new square-root domain first order all-pass filter based on the MOSFET square law is presented. The proposed filter is designed by using nonlinear mapping on the state variables of a state space description of the transfer function. To the best knowledge of the authors the filter is the first square-root domain first order all-pass structure designed by using state space synthesis method in the literature. The center frequency of the all-pass filter is not only attainable at megahertz frequencies but also tunable by an external bias current. The proposed filter operated 2.5 V supply voltage is constructed by current mirrors geometric mean circuits a linear transconductor circuit and a capacitor. SPICE simulations are given to approve the theoretical analysis.Article Citation - Scopus: 1A proposed model for candidate selection process in political parties based on fuzzy logic methodology(Association for Scientific Research, 2012) METE EMİNAĞAOĞLU; Yılmaz GÖKŞEN; ONUR DOĞAN; Eminağaoğlu, Mete; Gökşen, Yılmaz; Doğan, OnurClassical logic and classical set theorems are not sufficient enough when it isnecessary to deal with complex decision making problems which also involve humanexperiences. Some researches suggest that senior management usually makes intuitivedecisions in the process of selecting the candidates in political parties which brings outthe need to derive a new efficient robust and applicable method.In this study the qualitative characteristics and their significance level which could beused for the candidate selection process in political parties are determined. Thecandidate selection process consisting vague inputs is analyzed by fuzzy logicmethodology and a quantitative final score has been determined for the candidate. It hasbeen shown that the model provided some realistic and promising results which couldenable further studies to derive more optimized and enhanced models for similarpurposes.Article A Proposed New Approach for The Single Machine Scheduling Problem: Dynamic Programming(2024) Yucel Ozturkoglu; OMER OZTURKOGLU; Yeşim Deniz Özkan Özen; Özen, Yeşim Deniz Özkan; Ozturkoglu, Yucel; Ozturkoglu, OmerA traditional scheduling problem is one of the optimization problems that assign tasks to humans and machines in an optimal order. In real applications many jobs do not have a fixed processing time. During production some machines need to be cooled due to overheating. This activity which takes place outside periodic maintenance is called rate-modifying. During this time the job times increase with each passing second as Jobs wait to be assigned. The rate of deterioration due to this increase is called deteriorating jobs. This paper considers scheduling a set of deteriorating jobs with rate-modifying activity with a single processor. During the speed change activity the production process is halted resulting in increased completion times of jobs. The problem arose from the problem of a machine and an automatic production line. This problem is classified as an NP-Hard problem. The problem addressed by the study has been tried to obtain optimal results with different methods by considering different factors by many authors. When a detailed literature review is made it has been seen that no author has developed a dynamic programming model until today. The most significant advantage of dynamic programming models is that they provide solutions with the closest optimal result faster especially in solving problems classified as Np-Hard. Therefore a dynamic programming algorithm was developed for the first time for large job numbers of the focused problem. Therefore this study presents a dynamic programming algorithm to calculate the optimal solution. The algorithm's efficiency is proven on an extensive randomly generated sample data set. The results prove that the proposed algorithm provides the optimal solution with much less effort than the mathematical model.Article A real-time accurate positioning system using BLE and wireless mesh network in a shipyard environment(2022) Hilal KILINÇ; EKREM ÖZGÜRBÜZ; NALAN OZKURT; HASAN HUSEYIN ERKAN; Kılınç, Hilal; Özgürbüz, Ekrem; Ozkurt, Nalan; Erkan, Hasan HuseyınDigitalization of the shipyard environment is a challenging problem and also it is necessary for competing the international ship manufacturers. Thus this study introduced a real-time accurate positioning system that is an indispensable part of a digital manufacturing system. The system implementation and measurements took place in Sedef Shipyard the largest shipbuilding facility in Turkey. Since the shipyard includes indoor and outdoor environments Bluetooth Low Energy (BLE) systems provide the best solution for locating the staff. The most challenging problem is to determine the positions in the metallic surroundings. The constructed system solves this problem by placing gateways and sensors at essential locations and using a mesh network. With the designed user interface the position of the staff can be monitored accurately in real time and reports can be generated.Article A Sustainability Comparison of Traditional Supply Chains and Physical Internet Supply Chains Using Simulation(2019) Nazlıcan GÖZAÇAN; Özgür KABADURMUŞ; Kabadurmuş, Özgür; Gözaçan, NazlıcanSustainability is one of the most important topics that should be considered by every sector because ithelps to reduce the harmful environmental effects of operations. Supply chain operations have significantimpacts on environmental social and economic issues and therefore sustainable supply chains havebecome an important issue for the companies. Also Physical Internet (PI) is one of the recent researchtopics in supply chain literature and it helps to provide sustainability. The contribution of this study to theliterature is the comparison of traditional supply chain and PI structures with simulation in terms ofsustainability. The simulation models are tested on realistic but hypothetical case studies. Each simulationmodel consists of three echelons (supplier distribution center and retailer) and is developed by usingARENA 14.0 software. The PI and the traditional are compared according to carbon emissions and theresults are discussed in detail. The results show that the emission level of PI is significantly lower than theemission level of traditional supply chain structures. Also larger vehicle capacity reduces the total carbonemissions in both traditional supply chains and PI due to the reduced number of trips.Article Citation - WoS: 1Citation - Scopus: 2A Symmetrical-Asymmetrical Fault Characteristics Analysis within Cogeneration Power Plant in Izmir Turkey: An Experimental Assessment(Gazi Univ, 2022) hacer sekerci oztura; sezai polat; Polat, Sezai; Oztura, Hacer Sekerci; Sekerci Oztura, HacerThe analysis of the short circuit should be understood very well in order to make correct designs in the power systems such as the safety of the personnel and the equipment the selection of the safety relays the circuit breaker selection and the selection of the appropriate conductor section. In this study the parameters about the short circuit and the techniques of calculating the faults in system and the necessary theoretical knowledge for the short circuit fault to be understood better have been given. The effect on the distributed generation and the grid which is caused by the possible short circuit faults have been simulated by being modeled in PSS/Sincal and by using the real grid parameters with cogeneration power plant in Izmir Turkey. The real short circuit fault results measured from the power plant and the grid and the results obtained from the software program have been compared and it has been determined that there is not a significant difference between them. Thus it has been emphasized that it is correct to simulate before investing in a power system in for the purpose of restrain the faults during the designing and working before the application. It allows the designer to design new power plant as good as plan expansion of existing power plants with higher degree of precision. Considering the prices of protection equipment which has a large part in system design this way would allow designer to reduce the cost of the protective equipment and remaining stability.
