WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/20.500.11779/256

Browse

Now showing 1 - 20 of 142

Citation - WoS: 7
Citation - Scopus: 4
2D Modeling Temperature Development of Mass Concrete Structures at Early Age
(FIB. The International Federation for Structural Concrete, 2018) Yikici, T.A.; Chen, R.H.L.
In this paper, a 2D finite volume analysis methodology was used to predict temperature development within three different bridge pier caps. MATLAB® was employed to generate a program that solves the governing heat transfer equation where development of thermo-physical concrete properties was defined as a function of degree of hydration. The rate of heat generation was obtained experimentally via adiabatic calorimetry and the activation energy was determined following the ASTM C 1074 procedure to implement equivalent age concept. 2D finite volume analysis results were presented in comparison with the recorded concrete temperatures from the field. Accordingly, temperature time histories at the center and the side surface of the bridge pier caps were predicted reasonably well using the concrete mixture information and the measured concrete hydration properties. © 2022 Elsevier B.V., All rights reserved.
A Historical Perspective To Fabrication in Architecture for Preserving Heritage
(Education and research in Computer Aided Architectural Design in Europe, 2019) Özgan, Sibel Yasemin; Özkar, Mine; Hamzaoğlu, Begüm
Digital technologies have recently been at the forefront of the causal link between making and design. A growing number of architecture programs of universities incorporates fabrication to the educational environment, and even to the curriculum. Fabrication technology is now considered among the set of tools students are expected to acquire a basic knowledge of and skills in. Nevertheless, the pedagogical potential of fabrication in communicating traditions of making is underused in an oversight of the continuity of the relevant know-how. Our position is that traditions of making can be the subject matter of fabrication with the objective to remedy the role of fabrication tools in architectural history, sustainable architectural production, and in the field of digital heritage. In this paper, we report on two comparative studies that illustrate how the instrumental factors of two historical crafts can be articulated using fabrication. © 2019, Education and research in Computer Aided Architectural Design in Europe. All rights reserved.
Citation - Scopus: 1
A Microwave Imaging Scheme for Detection of Pulmonary Edema and Hemorrhage
(IEEE, 2022) Ertek, Didem; Kucuk, Gokhan; Bilgin, Egemen
The microwave imaging systems have the potential to present a cost effective and less hazardous alternative to conventional medical imaging techniques. In this paper, a Contrast Source Inversion method based microwave imaging scheme is proposed and tested for the detection of pulmonary edema and hemorrhage. To this end, a realistic human torso phantom is used, and the electromagnetic parameters of the human tissues is determined via Cole-Cole model. The scattered field is simulated via Method of Moments at the operating frequency of 350 MHz, and a 50 dB white Gaussian noise is added to model a realistic measurement setup. The numerical tests performed with the proposed technique suggest that the method can be used to locate the pulmonary edema and hemorrhage, and it is capable of distinguishing these two medical conditions successfully.
A Practical PCB-Based Framework for Spiking Neural Networks with a Half-Adder Example
(IEEE, 2025) Cikikci, Sevde Vuslat; Orek, Eren; Aysoy, Ayhan; Ozgen, Ali Kagan; Yavuz, Arda; Ayhan, Tuba
This paper addresses the half-adder problem using Spiking Neural Networks (SNNs). In a previous study, the XOR operation was successfully realized on a breadboard and in this study it is integrated into the half-adder structure. The system uses input signals at frequencies of 50 Hz and 100 Hz and the neurons are generated by the Leaky Integrate and Fire (LIF) model. Unlike other neuron models, the LIF model is less complex. In addition, it was preferred because of its biological meaningfulness compared to the Integrate and Fire model. The network, consisting of 18 neurons in total, shows that basic arithmetic operations can be performed with SNN. Overall, this study demonstrates that basic logic operations can be implemented in neural networks, thus providing new perspectives for digital calculation. The successful solution of the Half Adder problem using SNNs not only proves the calculation capabilities of SNNs, but also opens new perspectives for the development of more complex logical circuits using these biologically inspired neural circuits.
A Strategic Management Approach To Financial Management Practices in Small and Medium Sized Businesses
(Emerald Group Publishing Ltd., 2015) Karadağ, Hande
...
Citation - Scopus: 2
A Visualization Platfom for Disk Failure Analysis
(IEEE, 2018) Arslan, Şuayb Şefik; Yiğit, İbrahim Onuralp; Zeydan, Engin
It has become a norm rather than an exception to observe multiple disks malfunctioning or whole disk failures in places like big data centers where thousands of drives operate simultaneously. Data that resides on these devices is typically protected by replication or erasure coding for long-term durable storage. However, to be able to optimize data protection methods, real life disk failure trends need to be modeled. Modelling helps us build insights while in the design phase and properly optimize protection methods for a given application. In this study, we developed a visualization platform in light of disk failure data provided by BackBlaze, and extracted useful statistical information such as failure rate and model-based time to failure distributions. Finally, simple modeling is performed for disk failure predictions to alarm and take necessary system-wide precautions.
Citation - Scopus: 1
Adaptive Boosting of Dnn Ensembles for Brain-Computer Interface Spellers
(IEEE, 2021) Çatak, Yiğit; Aksoy, Can; Özkan, Hüseyin; Güney, Osman Berke; Koç, Emirhan; Arslan, Şuayb Şefik
Steady-state visual evoked potentials (SSVEP) are commonly used in brain computer interface (BCI) applications such as spelling systems, due to their advantages over other paradigms. In this study, we develop a method for SSVEP-based BCI speller systems, using a known deep neural network (DNN), which includes transfer and ensemble learning techniques. We test performance of our method on publicly available benchmark and BETA datasets with leave-one-subject-out procedure. Our method consists of two stages. In the first stage, a global DNN is trained using data from all subjects except one subject that is excluded for testing. In the second stage, the global model is fine-tuned to each subject whose data are used in the training. Combining the responses of trained DNNs with different weights for each test subject, rather than an equal weight, provide better performance as brain signals may differ significantly between individuals. To this end, weights of DNNs are learnt with SAMME algorithm with using data belonging to the test subject. Our method significantly outperforms canonical correlation analysis (CCA) and filter bank canonical correlation analysis (FBCCA) methods.
Citation - WoS: 2
Citation - Scopus: 10
An Fpga Implementation of a Risc-V Based Soc System for Image Processing Applications
(IEEE, 2021) Gholizadehazari, Erfan; Ayhan, Tuba; Ors, Berna
The Laplacian filter is one of the fundamental applications in image processing. In our work, the Laplacian filter has been applied to an image, and both hardware and software implementation of the filter has been studied. Our system consists of an OV7670 Camera module, Nexys 4 DDR FPGA board and VGA monitor to display the processed video stream. Mentioned process has forwarding tasks: camera module captures raw RGB data and writes to RAM, Laplacian filter IP processes raw image and the results written back to memory. VGA modules show output images to monitor. The Laplacian filter part considered in hardware and software implementation is compared in terms of time and area.
Citation - WoS: 14
Citation - Scopus: 40
An Overview of Blockchain Technologies: Principles, Opportunities and Challenges
(IEEE, 2018) Arslan, Şuayb Şefik; Mermer, Gültekin Berahan; Zeydan, Engin
Blokzincir, toplumumuzun birbiriyle iletişim kurma ve ticaret yapma biçiminde devrim yapma potansiyeline sahip, yakın zamanda ortaya çıkmış olan bir teknolojidir. Bu teknolojinin sağladığı en önemli avantaj aracı gerektiren bir oluşumda güvenilir bir merkezi kuruma ihtiyaç duymadan değer taşıyan işlemleri değiş tokuş edebilmesidir. Ayrıca, veri bütünlüğü, dahili orijinallik ve kullanıcı şeffaflığı sağlayabilir. Blokzincir, birçok yenilikçi uygulamanın temel alınacağı yeni internet olarak görülebilir. Bu çalışmada, genel çalışma prensibi, oluşan fırsatlar ve ileride karşılaşılabilecek zorlukları içerecek şekilde güncel blokzincir teknolojilerinin genel bir görünümünü sunmaktayız.
Citation - Scopus: 3
An Xml Parser for Turkish Wikipedia
(IEEE, 2019) Demir, Şeniz; Vardar, Uluç Furkan; Devran, İlkay Tevfik
Nowadays, visual and written data that can be easily accessed over the internet has enabled the development of research in many different fields. However, the availability of data is not sufficient by itself. It is of great importance that these data can be effectively utilized and interpreted in accordance with the requirements. Access to written content in the Wikipedia encyclopedia, which is becoming increasingly common in Turkish natural language processing, can be done via XML dumps. In this study, our aim is to develop and demonstrate the applicability of an XML parser for the processing of Turkish Wikipedia dumps. The use of the open-source parser, which allows information extraction at different levels of granularity, is reported on pages containing biography infoboxes and textual contents.
Anamorphic Projection as a Novel Game Mechanic for Investigating Impossible Spaces in 3D Puzzle Games
(IEEE Computer Society, 2025) Aydındoğan, Irem; Alaçam, Sema
This study introduces a novel game mechanic for 3D puzzle games based on anamorphic projection to explore impossible spaces. By using perspective-driven spatial interactions, the mechanic creates environments that challenge conventional Euclidean logic. Players advance by aligning their viewpoint with distorted projections, making perception a central element of gameplay. A usability test with 33 participants assessed the mechanic's effectiveness through a structured questionnaire focusing on six dimensions: Ease of Control, Goals and Rules, Challenge, Mastery, Curiosity, and Immersion. Results indicate high engagement and cognitive stimulation, especially in mastery and goal clarity. These findings highlight the potential of anamorphic projection to support perceptually rich and mentally engaging puzzle experiences in future game design. © 2025 Elsevier B.V., All rights reserved.
Citation - WoS: 2
Citation - Scopus: 2
Approximate Closed-Form Solutions for Vibration of Nano-Beams of Local/Non-local Mixture
(Springer, 2022) Ruta, Giuseppe; Eroğlu, Uğurcan
This paper presents an approach to natural vibration of nano-beams by a linear elastic constitutive law based on a mixture of local and non-local contributions, the latter based on Eringen's model. A perturbation in terms of an evolution parameter lets incremental field equations be derived; another perturbation in terms of the non-local volume fraction yields the variation of the natural angular frequencies and modes with the 'small' amount of non-locality. The latter perturbation does not need to comply with the so-called constitutive boundary conditions, the physical interpretation of which is still debated. The possibility to find closed-form solutions is highlighted following a thorough discussion on the compatibility conditions needed to solve the steps of the perturbation hierarchy; some paradigmatic examples are presented and duly commented.
Citation - WoS: 1
Citation - Scopus: 1
Average Bandwidth-Cost Vs. Storage Trade-Off for Bs-Assisted Distributed Storage Networks
(IEEE, 2021) Tengiz, Ayse Ceyda; Haytaoğlu, Elif; Pusane, Ali Emre; Arslan, Şuayb Şefik; Pourmandi, Massoud
In this study, we consider a hierarchically structured base station (BS)-assisted cellular system equipped with a backend distributed data storage in which nodes randomly arrive and depart the cell. We numerically motivate and characterize the fundamental trade-off between the average repair bandwidth cost versus storage space where BS communication cost (higher than that of local) and link capacity constraints exist while the number of failed nodes can vary dynamically. We establish the capacity region that is most relevant to 5G and beyond networks, which are layered by design. We hope that this study shall motivate novel regeneration code constructions that will be able to achieve the presented limits.
Citation - WoS: 58
Bidirectional Recurrent Neural Network Language Models for Automatic Speech Recognition
(2015) Chen, Stanley; Sethy, Abhinav; Ramabhadran, Bhuvana; Arısoy, Ebru
Recurrent neural network language models have enjoyed great success in speech recognition, partially due to their ability to model longer-distance context than word n-gram models. In recurrent neural networks (RNNs), contextual information from past inputs is modeled with the help of recurrent connections at the hidden layer, while Long Short-Term Memory (LSTM) neural networks are RNNs that contain units that can store values for arbitrary amounts of time. While conventional unidirectional networks predict outputs from only past inputs, one can build bidirectional networks that also condition on future inputs. In this paper, we propose applying bidirectional RNNs and LSTM neural networks to language modeling for speech recognition. We discuss issues that arise when utilizing bidirectional models for speech, and compare unidirectional and bidirectional models on an English Broadcast News transcription task. We find that bidirectional RNNs significantly outperform unidirectional RNNs, but bidirectional LSTMs do not provide any further gain over their unidirectional counterparts.
Citation - Scopus: 1
Biology, Real Time and Multimodal Design Cell-Signaling as a Realtime Principle in Multimodal Design
(2015) Teixeira, Frederico Fialho
The common understanding of morphogenesis implies a three-dimensional evolutionary change in form witnessed in the developmental process of an organism. This evolutionary process emerges from cell growth, cellular differentiation and environmental changes that generate specific conditions between genotype and phenotype. The complex nature of these aspects is intrinsic to evolutionary biology, and its accurate implementation in bio-generated architectures potentiates a twofold understanding of different morphogenetic strategies and its spatial consequences. Within this premise the morphogenetic factors of cell-differentiation and cell-signaling become a crucial aspect in a real-time communication system between an archetype and space, thus performing within particular modes in which design correlates to space. The paper hypothesizes and tests the use of Cell-Signaling as system of communication that governs fundamental cellular activities within the process of Gastrulation. This process occurs in early cell-embryo development and where communication between cells is favorably active and cellular the structure is established. The Emosphera project is a technical re-contextualization of this specific morphogenetic process. The principles denote a genetic code of the object can be scripted in a CAD environment and reproduced real-time by means of communication through a multimedia platform, which render form as a consequential aspect.
Citation - WoS: 35
Citation - Scopus: 72
Blockchain Technology and Sustainability in Supply Chains and a Closer Look at Different Industries: a Mixed Method Approach
(MDPI, 2022) Güner, Elif; Ayan, Büsra; Son-Turan, Semen
Background: This study presents a comprehensive review of blockchain technology with a sustainability orientation in supply chains and logistics. Methods: The publications are extracted from the Scopus and Web of Science databases, comprising 552 publications between 2017 and 2022. Several bibliometric laws and techniques, namely three-field analysis, Bradford’s Law, Lotka’s Law, and thematic maps, are applied in R with the bibliometrix package. Content analysis is also carried out based on 185 publications to appreciate the industry-based view of the field. Results: The bibliometric results indicate that this field is on the rise. Authors, sources, affiliations, countries, keywords, and their relationships are also addressed. The findings of the content analysis and thematic maps reveal that some of the most highlighted themes in the literature include traceability, COVID-19, the internet of things, and Industry 4.0. The most popular industry in this field is discovered to be food and agriculture. Conclusions: This paper contributes to the still relatively scarce literature on how blockchain technology fosters sustainable supply chains and logistics, providing a closer look at blockchain use, methodologies, and future directions for different industries concerning food, agriculture, fashion, textile and apparel, manufacturing, automotive, maritime and shipping, healthcare and pharmaceutical, mining and mineral, and energy. © 2022 by the authors.
Çevrim-İçi Matematik Öğretimi Alan Deneyiminde Teori ve Pratik Arasındaki Mesafe Üzerine Bir İnceleme
(Mehmet Tekerek, 2025) Ӧlmez, İbrahim; Pekkan, Zelha Tunc; Birgili, Bengi; Taylan, Rukiye Didem
Geçmiş çalışmalar, öğretmen adaylarının teori ve pratiği birleştirme becerisinin, derste öğrendiklerinipratiğe dökebilmek için artan öneminden bahsetmektedir. Bu çalışma, 23 matematik öğretmenliğiadayının bir matematik öğretmen eğitimi programındaki ders ve çevrim-içi matematik öğretimi alandeneyimlerini birleştirme becerisini incelemiştir. Bu çalışmanın verisini, öğretmen adaylarının birdönem boyu süren çevrim-içi ders verme deneyiminden önce gerçekleşen 24 video-kayıtlı ders planlamatoplantısının transkripleri ve Çevrim-içi Laboratuar Okulu’ndaki çevrim-içi ders anlatımlarından sonragerçekleşen 9 video-kayıtlı tüm sınıfın dahil olduğu tartışma toplantılarının transkripleri kapsamaktadır.Ayrıca, bu çalışmanın verisini öğretmen adaylarının çevrim-içi ders anlatımlarından sonra dersanlatımlarındaki ilginç ve önemli buldukları durumlar üzerine yazdıkları kısa notları da içermektedir.Sonuçlar, öğretmen adaylarının sıklıkla teori ve pratik arasındaki bağlantıları kurmakta zorlandıklarınıgöstermekte ve öğretmen eğitimcilerinin matematik öğretimi alan deneyimleri ödevlerinde daha fazladers entegrasyon fırsatlarını kullanmasını önermektedir. Ders öğretim üyelerinin amaçları, öğretmenadaylarının düşünümleri, ders planları ve tüm sınıfın dahil olduğu tartışma toplantıları gibi birden fazlaveri kaynaklarını kullanan bu çalışma, eğitim araştırması alanındaki var olan mesafenin kapanması içindeğerli bir nitel kanıt sunmaktadır
Citation - WoS: 3
Citation - Scopus: 3
Characterization of Viscoelastic Materials Using Free-Layered and Sandwiched Samples: Assessment and Recommendations
(Polish Physical Society, 2015) Özer, Mehmet Sait; Körük, Hasan; Şanlıtürk, Kenan Yüce
Viscoelastic materials are widely used in many applications in practice. However, determination of the elastic and damping properties of these materials is quite difficult in the sense that the identified results may contain high degree of uncertainty. The characterization of viscoelastic materials using the Oberst beam method, based on non-contact excitation and response measurements, is revisited in this paper. The effects of signal processing parameters such as frequency resolution in Frequency Response Function (FRF) measurements, as well as the effects of various single-degree-of-freedom modal analysis methods, including circle-fit, half-power and line-fit are investigated first. Then, the modal loss factors, Young's modulus and shear modulus of some sample viscoelastic materials are identified using both the free-layered and sandwiched samples. The results obtained from different tests are compared, discussed and some recommendations are made so as to identify the damping and elastic properties of typical viscoelastic materials with better accuracy. Analyses of a large number of FRF measurements show that the selection of the appropriate signal processing parameters and the use of appropriate modal analysis method can be very significant during the identification of viscoelastic materials. By following the approach presented in this paper, the damping and elastic properties of viscoelastic materials can be identified with better accuracy using either free-layered or sandwiched samples. The material properties obtained by this approach can be used for developing valid structural models and/or for damping optimization purposes.
Citation - WoS: 5
Citation - Scopus: 7
Cloud2hdd: Large-Scale Hdd Data Analysis on Cloud for Cloud Datacenters
(IEEE, 2020) Zeydan, Engin; Arslan, Şefik Şuayb
The main focus of this paper is to develop a distributed large scale data analysis platform for the opensource data of Backblaze cloud datacenter which consists of operational hard disk drive (HDD) information collected over an observable period of 2272 days (over 74 months). To carefully analyze the intrinsic characteristics of the hard disk behavior, we have exploited a large bolume of data and the benefits of Hadoop ecosystem as our big data processing engine. In other words, we have utilized a special distributed scheme on cloud for cloud HDD data, which is termed as Cloud2HDD. To classify the remaining lifetime of hard disk drives based on health indicators such as in-built S.M.A.R.T (Self-Monitoring, Analysis, and Reporting Technology) features, we used some of the state-of-the-art classification algorithms and compared their accuracy, precision, and recall rates simultaneously. In addition, importance of various S.M.A.R.T. features in predicting the true remaining lifetime of HDDs are identified. For instance, our analysis results indicate that Random Forest Classifier (RFC) can yield up to 94% accuracy with the highest precision and recall at a reasonable time by classifying the remaining lifetime of drives into one of three different classes, namely critical, high and low ideal states in comparison to other classification approaches based on a specific subset of S.M.A.R.T. features.
Citation - WoS: 2
Comparison of Earliest and Later Autobiographical Memories in Young and Middle-Aged Adults
(İstanbul Üniversitesi Yayınevi, 2019) Öner, Sezgin; Gülgöz, Sami; Demiray, Burcu; Ece, Berivan
The current study examined earliest memories of young and middle-aged adults in comparison to a recent autobiographical memory and a free-report one from any life phase. These three types of memories were compared in terms of their memory characteristics such as vividness, emotionality, importance, confidence, and rehearsal frequency. A total of 319 young (18-30 years) and 112 middle-aged (40-65 years) adults completed the online survey. Results showed that earliest memories were rated either similar to or lower than later memories in their memory characteristics. More specifically, they received lower ratings than freereport memories in all memory characteristics whereas they did not significantly differ from recent memories only in importance and emotionality. In addition, free-report memories were highest in emotionality, importance and rehearsal frequency whereas recent memories were highest in vividness and confidence ratings. Compared to young adults, middle-aged adults provided higher ratings for all memory characteristics in general, and they further recalled earliest memories from an older age. Finally, the order of reporting the three types of memories (earliest memory first versus recent memory first) was examined with respect to its potential influence on memory characteristics and dating of the recalled memories. Results displayed no significant effect of the reporting order on memory characteristics. Dating of the earliest and free-report memories, however, was significantly affected by the reporting order. The mean age for earliest memories was higher when it was retrieved following the recent memory compared to the reporting order in which earliest memories are retrieved and reported first. Overall, results indicated that earliest memories are not particularly special compared to later memories (e.g.,free-report memories) in terms of their memory characteristics, and they are vulnerable to experimental manipulation such as changing the reporting order just like other types of autobiographical memories.

Browse

Browsing WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection by Scopus Q "N/A"