Scopus İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12469/1248

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Citation - WoS: 7
Citation - Scopus: 11
A 1-kW wireless power transfer system for electric vehicle charging with hexagonal flat spiral coil
(Tubitak Scientific & Technical Research Council Turkey, 2021) Aydin, Emrullah; AydemIr, M. Timur
Wireless power transfer (WPT) technology is getting more attention in these days as a clean, safe, and easy alternative to charging batteries in several power levels. Different coil types and system structures have been proposed in the literature. Hexagonal coils, which have a common usage for low power applications, have not been well studied for high and mid power applications such as in electric vehicle (EV) battery charging. In order to fill this knowledge gap, the self and mutual inductance equations of a hexagonal coil are obtained, and these equations have been used to design a 1 kW WPT system with hexagonal coils for a mid-power stage EV charging. The theoretical and simulation results have been validated with an implementation in the laboratory and a DC-to-DC power efficiency of 85% is achieved across a 10 cm air gap between the perfect aligned coils. The misalignment performance of the system was observed for different positioning of the secondary coil, and the output power variation is given. In addition, the effect of shielding on magnetic field exposition of a driver sitting in an EV was obtained, and these simulation results were compared in order to check the compliance with international health standards.
2nd tourism and hospitality networking conference | RESNET’22
(Routledge, 2023) Serra, J.
[No abstract available]
Citation - WoS: 2
Citation - Scopus: 1
3D self-assemble formation of molybdenum disulfide (MoS2)-doped polyacrylamide (PAAm) composite hydrogels
(Tubitak Scientific & Technological Research Council Turkey, 2022) Durmaz, Sumeyye; Yildiz, Ekrem; Uysal, Bengu Ozugur; Pekcan, Onder
Polyacrylamide (PAAm), a renowned member of the hydrogel class, has many uses throughout a wide range of industrial processes, including water absorbed diapers, contact lenses, wastewater treatment, biomedical applications such as drug delivery vehicles and tissue engineering because of its physical stability, durability, flexibility easier shaping, and so on. PAAm also provides new functionalities after the incorporation of inorganic structures such as molybdenum disulfide (MoS2). During the copolymerization process, the transmittance of all samples reduced significantly after a particular time, referred to as the gel point. Microgels form a tree above the gel point as projected by Flory-Stockmayer classical theory. Because of microgels positioned at the junction points of the Cayley tree, the addition of MoS2 results in strong intramolecular crosslinking and looser composites. Moreover, fractal geometry provides a quantitative measure of randomness and thus permits characterization of random systems such as polymers. Fractal dimension of these polymer composites is calculated from power-law-dependent scattered intensity. It was also confirmed that a hydrogel rapidly formed within a few seconds, indicating a 3D network formation inside the gel. These materials may have a great potential for application in wearable and implantable electronics due to this highly desired 3D self-assemble feature.
Citation - WoS: 2
Citation - Scopus: 3
3d-Printed Actuator-Based Beam-Steering Approach for Improved Physical Layer Security in Visible Light Communication
(Optica Publishing Group, 2022) Erdem, Mehmet Can; Gurcuoglu, Oguz; Panayırcı, Erdal; Kurt, Gunes Karabulut; Ferhanoglu, Onur
In this study, we present the design, manufacture, and implementation of a 3D-printed lens scanner-based beam steering for use in visible light communication (VLC) applications. The 5 cm x 5 cm scanner is designed for low-cost 3D printing with fused deposition modeling using polylactic acid. Scanning is facilitated through electromagnetic actuation of the lens frame, carrying a conventional 25 mm lens, from two nearly orthogonal directions. The serpentine spring that connects the lens frame to the external frame is tailored to offer similar spring constants in the directions of actuation and has minimal (<1.5 mm) sag due to the mass of the lens. The manufactured actuator was integrated on a miniaturized VLC test bed (70 cm x 40 cm x 40 cm). Using the test bed, we characterized the applied voltage versus beam displacement behavior of the actuator in the lateral plane and demonstrated beam steering on amoving target with face-recognition feedback. The proposed scheme was targeted to offer an improved security measure in VLC through tracking the legitimate receiver (i.e., via face recognition) and uses the feedback to steer the focused light onto the targeted device. The joint use of focusing and steering features allows for the legitimate receiver to roam within the room while enjoying the improved secrecy due to the focused light. We calculate the secrecy capacity for the demonstrated approach, which compares favorably with a number of jamming, spatial modulation, and beam-forming counterparts. The presented actuator can be used with larger room dimensions, yet upscaling to larger illumination units will require the use of a lens having smaller focus to address a larger total steering angle. (C) 2022 Optica Publishing Group
Citation - Scopus: 2
Accented Essays: Documentary as Artistic Practice in Contemporary Audiovisual Works From Turkey
(Routledge, 2019) Akçalı,E.
This article looks at the use of documentary filmmaking in contemporary artistic practices in Turkey, specifically focusing on three works that adopt a first-person, subjective viewpoint: Didem Pekün’s Of Dice and Men (2016), Şener Özmen’s How to Tell of Peace to a Living Dove? (2015), and Aykan Safoğlu’s Off-White Tulips (2013). Made by artists in transition, these films tackle themes of belonging and identity through stylistic choices proper to essayistic filmmaking, which allow these works to be regarded as accented essays. The personal questions raised through the aesthetics they employ become relevant to collective issues of culture, history, and memory, offering an alternative understanding of the social context, which was largely affected by the political events during the period in which they were made. © 2019, © 2019 Critical Arts.
Citation - WoS: 4
Citation - Scopus: 8
Accurate Indoor Positioning With Ultra-Wide Band Sensors
(Tubitak, 2020) Arsan, Taner
Ultra-wide band is one of the emerging indoor positioning technologies. In the application phase, accuracy and interference are important criteria of indoor positioning systems. Not only the method used in positioning, but also the algorithms used in improving the accuracy is a key factor. In this paper, we tried to eliminate the effects of off-set and noise in the data of the ultra-wide band sensor-based indoor positioning system. For this purpose, optimization algorithms and filters have been applied to the raw data, and the accuracy has been improved. A test bed with the dimensions of 7.35 m x 5.41 m and 50 cm x 50 cm grids has been selected, and a total of 27,000 measurements have been collected from 180 test points. The average positioning error of this test bed is calculated as 16.34 cm. Then, several combinations of algorithms are applied to raw data. The combination of Big Bang-Big Crunch algorithm for optimization, and then the Kalman Filter have yielded the most accurate results. Briefly, the average positioning error has been reduced from 16.34 cm to 7.43 cm.
Citation - Scopus: 5
Acute Myeloblastic Leukemia Achieving Complete Remission With Amifostine Alone
(2002) Öztürk, Ahmet Kutlu; Orhan, Bülent; Türken, Orhan; Etiz, Durmuş; Yaylacı, Mustafa; Üskent, Necdet
Amifostine, a phosphorylated thiol-amine, is known as a cytoprotective agent especially for cisplatin containing chemotherapies. Apart from the cytoprotective role, Amifostine could also be used in the treatment of hematologic malignancies such as myelodysplastic syndrome (MDS) and acute myeloblastic leukemia (AML), as a treatment option or for potentiating the effects of cytotoxic agents. We tried to use Amifostine in a patient with AML, which did not respond to conventional cytotoxic chemotherapy and aimed to publish the results. The patient was a 77-year-old male patient, he was diagnosed as AML by peripheral blood smear and bone marrow aspiration. Treatment commenced with low dose cytosine arabinoside (Ara-C) but the therapy should have ceased due to patient intolerance. The patient refused further therapy and he was offered to have Amifostine treatment. Amifostine was administered 200 mg/m2 three times a week, with ciprofloxacin, pentoxifyllin and dexamethasone. Dramatic response was obtained after 8 weeks of administration. Blast rate was reduced from 35 to 7% in bone marrow aspiration; pancytopenia was restored to normal levels. This remission was maintained through 8 more weeks. Amifostine treatment was restarted after he relapsed but this time he did not respond to the treatment and died of gastrointestinal bleeding on the 8th week of treatment.
Citation - WoS: 23
Citation - Scopus: 35
An advanced Grey Wolf Optimization Algorithm and its application to planning problem in smart grids
(Springer, 2022) Ahmadi, Bahman; Younesi, Soheil; Ceylan, Oguzhan; Ozdemir, Aydogan
Due to the complex mathematical structures of the models in engineering, heuristic methods which do not require derivative are developed. This paper improves recently developed Grey Wolf Optimization Algorithm by extending it with three new features: namely presenting a new formulation for evaluating the positions of search agents, applying mirroring distance to the variables violating the limits, and proposing a dynamic decision approach for each agent either in exploration or exploitation phases. The performance of Advanced Grey Wolf Optimization (AGWO) method is tested using several optimization test functions and compared to several heuristic algorithms. Moreover, a planning problem in smart grids is solved by considering different objective functions using 33 and 141 bus distribution test systems. From the numerical simulation results, we observe that, AGWO is able to find the best results compared to other methods from 10 and 9 out of 13 test functions for 30 and 60 variables, respectively. Similar to this, it finds best function values for 5 out of 10 fixed number of variable test functions. Also, the result of the CEC-C06 2019 benchmark functions shows that AGWO outperforms 8 for optimization problems from 10. In power distribution system planning problem, better objective function values were determined by using AGWO, resulting a better voltage profile, less losses, and less emission costs compared to solutions obtained by Grey Wolf Optimization (GWO) and Particle Swarm Optimization (PSO) algorithms.
Amplitude and Frequency Modulations With Cellular Neural Networks
(Springer, 2015) Tander, Baran; Özmen, Atilla
Amplitude and frequency modulations are still the most popular modulation techniques in data transmission at telecommunication systems such as radio and television broadcasting gsm etc. However the architectures of these individual systems are totally different. In this paper it is shown that a cellular neural network with an opposite-sign template can behave either as an amplitude or a frequency modulator. Firstly a brief information about these networks is given and then the amplitude and frequency surfaces of the generated quasi-sine oscillations are sketched with respect to various values of their cloning templates. Secondly it is proved that any of these types of modulations can be performed by only varying the template components without ever changing their structure. Finally a circuit is designed simulations are presented and performance of the proposed system is evaluated. The main contribution of this work is to show that both amplitude and frequency modulations can be realized under the same architecture with a simple technique specifically by treating the input signals as template components.
Citation - Scopus: 10
An Analysis of International Relations Academics in Turkey and Their Approaches To the Field: Trip 2014 Faculty Survey Results;
(International Relations Council of Turkey, 2016) Aydin,M.; Hisarlioğlu,F.; Yazgan,K.
Despite the increasing interest in the studies inquiring the limits, autonomous character of and the interactions between the International Relations (IR) discipline and other academic fields, the scope and scale of empirical research on these issues are relatively small. In order to contribute to the discussion on the limits and peculiarities of the IR discipline and to shed light on the development, current status and major characteristics of the IR studies in Turkey, its place in the global IR discipline and the views of IR scholars on major issues on the global, regional and national agenda, two surveys were conducted by the International Relations Council of Turkey (IRCT) in 2007 and 2009. Later on, the IRTC collaborated with the Institute for the Theory and Practice of International Relations at the College of William and Mary to conduct further surveys in 2011 and 2014. This paper presents findings of the last survey on Turkey, based on the worldwide research simultaneously conducted in 31 different countries in September 2014. © 2016, International Relations Council of Turkey. All rights reserved.
Citation - WoS: 2
Citation - Scopus: 2
Anatolia - Unveiling Its Multidisciplinary Landscape and Future Orientations
(Routledge Journals, Taylor & Francis Ltd, 2024) Kaurav, Rahul Pratap Singh; Singhania, Shubham; Kozak, Metin
Using methods such as Latent Dirichlet Allocation (LDA) and content analysis, this paper does a comprehensive analysis of Anatolia's contributions to tourism and hospitality research over the last 27 years, analyzing publishing trends, regional distribution, and topic evolution. The results show a significant increase in worldwide contributions, covering 92 nations, and an interdisciplinary strategy in line with the UN Sustainable Development Goal (UNSDG) 11. Important subject clusters are identified by the study, underscoring the journal's growing influence and its part in determining the course of future research. Through the identification of emergent topics, the study highlights Anatolia's engagement in varied topics and offers a strategic framework for future research.
Citation - WoS: 8
Citation - Scopus: 9
Apolipoprotein B Gene Variants Are Involved in the Determination of Blood Glucose and Lipid Levels in Patients With Non-Insulin Dependent Diabetes Mellitus
(Wiley, 2006) Duman, Belgin Süsleyici; Öztürk, Melek; Yilmazer, Selma; Çağatay, Penbe; Hatemi, Hüsrev
We have examined the frequency of the EcoRI XbaI and MspI RFLPs of the apolipoprotein B (apo 13) gene in I 10 type 2 diabetic patients and 9 1 healthy control subjects in order to ascertain whether variation in this gene may influence the development of non-insulin dependent diabetes mellitus (type 2 diabetes). Serum lipids including total-cholesterol (T-Chol) triacylglycerol (TAG) apolipoprotein E (apo E) apolipoprotein Al (apo Al) apolipoprotein B and lipoprotein (a) (Lp(a)) were analysed. Genomic DNA was extracted and the apo B polymorphic regions amplified by the polymerase chain reaction. Regions carrying EcoRI XbaI and MspI restriction sites present in the apo B gene were amplified and digested separately by the respective enzymes. No significant difference for genotypic frequencies was observed for the EcoRI XbaI and MspI restriction sites in type 2 diabetic patients as compared to controls. Type 2 diabetic patients and controls with EcoRI +/+ and XbaI +/+ genotypes had higher apo E levels. The MspI +/+ genotype is more frequent in the patient and control groups With elevated T-Chol. Furthermore the EcoRI -/- XbaI -/- and MspI +/+ genotypes were found to be significantly more frequent in type 2 diabetic patients with higher blood glucose levels. This study identifies the apo B gene polymorphisms in modulating plasma lipid/lipoprotein and glucose levels in patients with type 2 diabetes. Copyright 0 2005 John Wiley & Sons Ltd.
Citation - WoS: 11
Citation - Scopus: 11
Application of Epidemic Models To Phase Transitions
(Taylor & Francis Ltd, 2012) Bilge, Ayşe Hümeyra; Pekcan, Önder; Gürol, M. V.
The Susceptible-Infected-Recovered (SIR) and Susceptible-Exposed-Infected-Recovered (SEIR) models describe the spread of epidemics in a society. In the typical case, the ratio of the susceptible individuals fall from a value S-0 close to 1 to a final value S-f, while the ratio of recovered individuals rise from 0 to R-f = 1 - S-f. The sharp passage from the level zero to the level R-f allows also the modeling of phase transitions by the number of "recovered" individuals R(t) of the SIR or SEIR model. In this article, we model the sol-gel transition for polyacrylamide-sodium alginate (SA) composite with different concentrations of SA as SIR and SEIR dynamical systems by solving the corresponding differential equations numerically and we show that the phase transitions of "classical" and "percolation" types are represented, respectively, by the SEIR and SIR models.
Citation - WoS: 72
Citation - Scopus: 83
The Applications of Nature-Inspired Algorithms in Internet of Things-Based Healthcare Service: a Systematic Literature Review
(Wiley, 2024) Amiri, Zahra; Heidari, Arash; Zavvar, Mohammad; Navimipour, Nima Jafari; Esmaeilpour, Mansour
Nature-inspired algorithms revolve around the intersection of nature-inspired algorithms and the IoT within the healthcare domain. This domain addresses the emerging trends and potential synergies between nature-inspired computational approaches and IoT technologies for advancing healthcare services. Our research aims to fill gaps in addressing algorithmic integration challenges, real-world implementation issues, and the efficacy of nature-inspired algorithms in IoT-based healthcare. We provide insights into the practical aspects and limitations of such applications through a systematic literature review. Specifically, we address the need for a comprehensive understanding of the applications of nature-inspired algorithms in IoT-based healthcare, identifying gaps such as the lack of standardized evaluation metrics and studies on integration challenges and security considerations. By bridging these gaps, our paper offers insights and directions for future research in this domain, exploring the diverse landscape of nature-inspired algorithms in healthcare. Our chosen methodology is a Systematic Literature Review (SLR) to investigate related papers rigorously. Categorizing these algorithms into groups such as genetic algorithms, particle swarm optimization, cuckoo algorithms, ant colony optimization, other approaches, and hybrid methods, we employ meticulous classification based on critical criteria. MATLAB emerges as the predominant programming language, constituting 37.9% of cases, showcasing a prevalent choice among researchers. Our evaluation emphasizes adaptability as the paramount parameter, accounting for 18.4% of considerations. By shedding light on attributes, limitations, and potential directions for future research and development, this review aims to contribute to a comprehensive understanding of nature-inspired algorithms in the dynamic landscape of IoT-based healthcare services. Providing a complete overview of the current issues associated with nature-inspired algorithms in IoT-based healthcare services. Providing a thorough overview of present methodologies for IoT-based healthcare services in research studies; Evaluating each region that tailored nature-inspired algorithms with many perspectives such as advantages, restrictions, datasets, security involvement, and simulation stings; Outlining the critical aspects that motivate the cited approaches to enhance future research; Illustrating descriptions of certain IoT-based healthcare services used in various studies. image
Citation - Scopus: 13
The Applications of the Routing Protocol for Low-Power and Lossy Networks (rpl) on the Internet of Mobile Things
(John Wiley and Sons Ltd, 2022) Ghanbari, Z.; Navimipour, N.J.; Hosseinzadeh, M.; Shakeri, H.; Darwesh, A.
Internet of Mobile Things (IoMT) have become very popular recently. The routing protocol for low power and lossy networks (RPL) is standardized for static topologies. However, mobility is the nature of IoT. Mobility serves as a promising candidate to harness hand-off time issues, delay in data transmission, overhead, and low packet delivery rate (PDR) effectively. This study presents a comprehensive account of the mobility-aware RPL-based routing protocols to validate and compare the experimental results. Remarkably, classification methods are used in many articles. The aim is to introduce significant research efforts to improve RPL objective functions (OF) performance in hand-off time, PDR, delay, overhead, and so forth. In this regard, a complete analysis of the existing routing protocols in IoMT has been presented to compare the results. The main focus of this study is on approaches that proposed new OFs for supporting mobility in RPL. Two main categories are considered to study RPL-based routing protocol mechanisms: The mobile and static sink. The related studies on the mobile sink are divided into three groups: Single metric-based OF, composite metric OF, and hybrid routing protocols. Also, the related works based on the static sink are categorized into four groups: Fuzzy logic-based OF, trickle timer-based OF, composite metrics-based OF, and modification control messages-based OF approach. This paper presents a detailed comparison of mechanisms in each category. It also highlights the pros, cons, open issues, and evaluated metrics of each paper. Besides, challenges of mobility in the RPL-based routing protocol mechanism in IoMT for future studies. © 2022 John Wiley & Sons Ltd.
Citation - WoS: 7
Citation - Scopus: 10
Artificial Neural Network Based Estimation of Sparse Multipath Channels in Ofdm Systems
(SPRINGER, VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS, 2021-01) Şenol, Habib; Abdur Rehman Bin, Tahir; Özmen, Atilla
In order to increase the transceiver performance in frequency selective fading channel environment, orthogonal frequency division multiplexing (OFDM) system is used to combat inter-symbol-interference. In this work, a channel estimation scheme for an OFDM system in the presence of sparse multipath channel is studied using the artificial neural networks (ANN). By means of ANN's learning capability, it is shown that how to model and obtain a channel estimate and how it allows the proposed technique to give a better system throughput. The performance of proposed method is compared with the Matching Pursuit (MP) and Orthogonal MP (OMP) algorithms that are commonly used in compressed sensing literature in order to estimate delay locations and tap coefficients of a sparse multipath channel. In this work, we propose a performance- efficient ANN based sparse channel estimator with lower computational cost than that of MP and OMP based channel estimators. Even though there is a slight performance lost in a few simulation scenarios in which we have lower computational complexity advantage, in most scenarios, our computer simulations corroborate that our low complexity ANN based channel estimator has better mean squared error and the corresponding symbol error rate performances comparing with MP and OMP algorithms.
Citation - WoS: 2
Citation - Scopus: 3
Aryl Butenoic Acid Derivatives as a New Class of Histone Deacetylase Inhibitors: Synthesis in Vitro Evaluation and Molecular Docking Studies
(Scientific Technical Research Council Turkey-Tubitak, 2014) Esiyok, Peruze Ayhan; Seven, özlem; Eymur, Guluzar; Tatar, Gamze Bora; Erden, Didem Dayangaç; Yelekçi, Kemal; Yurter, Hayat; Demir, Ayhan S.
New aryl butenoic acid derivatives have been synthesized by combining hydroxy- or methoxy-substituted phenyl rings as the capping group with a double bond in the short linker as well as metal binding groups enoic ester and salts bearing either methyl or morpholine. These compounds have been shown to possess promising histone deacetylase inhibition activities via in vitro fluorometric assay and molecular docking studies.
Citation - WoS: 1
Citation - Scopus: 1
Assesment of soft error sensitivity of power flow analysis
(Gazi Univ, Fac Engineering Architecture, 2023) Yetkin, Emrullah Fatih
Today's power systems are large and interconnected to each other with many buses, lines, loads, and generators. Even the solution of a single snapshot of the system for specific conditions requires the solution of systems of equations with large sizes. Thus, to obtain the results in a reasonable time for large problems like electrical power flow simulations, modern large computational environments should be employed. However, because of the increasing number of components in the modern computational environment, the possibility of soft errors also increases. Soft errors can be defined as failures arising from several fluctuations due to x-rays, cosmic particle effects, etc. These types of errors usually appear at any time of computation as a bit-flip in any floating-point operations. In this paper, we will investigate the soft-error effects on large-scale power flow simulations. Generally, power flow calculations are performed by using Newton Raphson Method. The system is modeled by nonlinear equations and the solution process requires a linear solver is employed to take the inverse of the Jacobian matrix at each iteration. In this study, the soft-error sensitivity of the numerical methods used in load flow was examined, and the problems that may be encountered were revealed.
Assessing the Impact of Customer Experience Quality on Customer Perceived Value and Marketing Outcomes
(Taylor & Francis Ltd, 2025) Demir, Ozge; Karaosmanoglu, Elif; Uray, Nimet
This research explores the link between customer experience, value, and marketing outcomes, with emphasis on contextual adaptability, employing a multi-group structural equations modeling (SEM) approach. It shows that customer experience quality (CXQ) is invariant across two services, banking and TV broadcasting. SEM results demonstrate that customer loyalty is mainly influenced by functional value-more so than economic or social values. However, what drives functional value differ: For banking, consumers' evaluations of three CXQ dimensions, ease of access, monetary experience, and customer-centric processes predict functional value. In the TV subscription service however, functional value is largely driven by customer-centric processes.
Citation - WoS: 3
Citation - Scopus: 4
Assessing the Impact of Minor Modifications on the Interior Structure of Gru: Gru1 and Gru2
(Wiley, 2022) Yigit, Gulsum; Amasyali, Mehmet Fatih
In this study, two GRU variants named GRU1 and GRU2 are proposed by employing simple changes to the internal structure of the standard GRU, which is one of the popular RNN variants. Comparative experiments are conducted on four problems: language modeling, question answering, addition task, and sentiment analysis. Moreover, in the addition task, curriculum learning and anti-curriculum learning strategies, which extend the training data having examples from easy to hard or from hard to easy, are comparatively evaluated. Accordingly, the GRU1 and GRU2 variants outperformed the standard GRU. In addition, the curriculum learning approach, in which the training data is expanded from easy to difficult, improves the performance considerably.

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