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Permanent URI for this collectionhttps://hdl.handle.net/20.500.14365/4772

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Impact location effects on ballistic performance of checkerboard-formation ceramic sphere armor
(ITU Press - International Congress on New Trends in Mechanics, 2025) Aktaş, Latif Tibet; Çevik, Mehmet
This study explores the influence of localized impact positions on the ballistic performance of modular ceramic armor systems. Utilizing a previously validated finite element model based on experimental data, simulations were conducted on an armor panel composed of alumina ceramic spheres arranged in a checkerboard configuration. The selected sphere diameter and layout had been previously identified as optimal for energy dissipation in high-velocity projectile impacts. In this extended analysis, the effect of varying projectile impact locations across the ceramic surface was evaluated. Rather than assuming central impacts, the study considered more realistic scenarios where projectiles may strike the edges of ceramic elements, vertical and horizontal locations between them, or the interstitial voids that naturally occur in such configurations. The findings indicate that the location of impact significantly alters the armor’s ability to absorb and dissipate kinetic energy. Certain locations were found to enhance resistance, while others allowed more efficient projectile penetration. These results underscore the importance of incorporating spatial variability into the design of advanced ceramic-based protective structures and highlight the need for optimizing geometric configurations not only by material and layout, but also by accounting for the probabilistic nature of real-world ballistic interactions.
Diameter and pattern effects of Al₂O₃ balls on ballistic strength of metal–ceramic composites
(İzmir Katip Çelebi Üniversitesi Yayınları - 6th International Students Science Congress, 2022) Aktaş, Latif Tibet; Çevik, Mehmet
In composite materials made from metals and ceramics, a metallic substrate material is reinforced with ceramic hardened particles. This combination makes it possible to combine the low weightiness of the metal with the resistance of ceramics. Used metals in those types of composites have greater density than the ceramics, so relatively, metals are heavier than ceramics, but in metal-ceramic composite applications, the metal parts are used in small quantities as in thin slices. These types of composites can combine attractive properties of both a ceramic, such as high temperature resistance and hardness, and those of a metal, such as the ability to undergo plastic deformation. Metal-ceramic armors are used in the fields where the weight factor is not crucial yet important for mobilization. Metal-ceramic composites show their unique values in armor technologies especially in vehicle protection applications. Ceramic balls offer advantages such as being lightweight, lower friction resistance, high temperature resistance, higher rigidity, higher hardness, and higher corrosion resistance than metallic composite core, but these properties belong to the material nature. In ballistic applications like high velocity impact situations, spherical shape, theoretically must have an effect on bullet trajectory. Because of the curved surface of a sphere, chances are a projectile hits any spherical surface obliquely. That means the projectile loses some of its kinetic energy by transferring it into the sphere and changing course into another trajectory axis. Shao et al. showed this trajectory deflection effect vividly.
Optimization study of ballistic impact tests on carbon–carbon composites
(İzmir Katip Çelebi Üniversitesi Yayınları - 4th International Students Science Congress, 2020) Aktaş, Latif Tibet; Aydın, Levent
In this study it is intended to optimize a high velocity impact case of a composite plate. The case is selected from the literature based on its dataset properties (e.g. amount of inputs and outputs, number of tests, physical relations with real life situations and relations between the properties studied on). The base study focused on failure response of advanced carbon-carbon composites under high velocity impacts. In the present study, two unique models are introduced within the scope of the present study as dimensionless damage areas of front and back sides of the composite plate. Multiple nonlinear regression method is used for objective functions of the optimization problem. The prediction models found in the present study are in first order trigonometric multiple nonlinear regression form; thus, these models can be considered as the basic prediction functions of high velocity impact response of carboncarbon composites under high temperatures, in processing power terms. Since the determination coefficient values have been found quite similar with the ones in the base study, the presented models in this study can be considered successful to predict the results.
Finite element analysis of material and parameter effects in ballistic armors
(İzmir International Student Association - 2nd International Students Science Congress, 2018) Aktaş, Latif Tibet; Çevik, Mehmet
The literature about the ballistic armors are mostly focused on 2 or 3 different parameter effects. The aim of this study, differently, is to find and compare the effects of specific materials on protection of composite ballistic armor plates against high-velocity projectile impact. The effects of stacking sequence for different materials, projectile type, target plate shape and impact obliquity are investigated individually. It is shown that the proposed stacking sequence decelerates the residual velocity of the projectile better than the other considered arrangements. The average percentage of kinetic energy absorption of rectangular shaped Kevlar 29/epoxy plate is considerably higher than that of circular shaped Kevlar 29/epoxy plate.
Designing for Social Innovation: Apps as a Tool for CoCreation
(Pensoft Publishers - 10th World Summit: Civil Engineering-Architecture-Urban Planning Congress (CAUSummit 2025), 2025-10-17) Ercan, İrem; Kan, Didem; Mengi, Onur
A shared understanding of active participation of many urban actors is necessary for a socially sustainable urban environment. This study explores how various urban stakeholders including government agencies, city collectives, citizens, academic institutions, and businesses co-create by leveraging their unique skills and exchanging work and knowledge via an online platform in order to foster social innovation at urban scale. The present research hypothesizes that establishing a participatory mobile application enabling city inhabitants to actively engage and assume shared responsibilities in urban processes can strengthen the sense of belonging of citizens. The design research methodology employed in this study is rooted in the context of co-creation and participatory design. The study is structured around the hypothetical development of the Give a Hand mobile application, a participatory platform designed to make education, health, culture, and art services more accessible for everyone. By enabling participation and co-creation among city inhabitants, the platform aims to optimize public service delivery, saving both time and resources as well as to achieve more inclusive urban environments. More importantly, this platform facilitates urban value creation through mechanisms of volunteering and donations, contributing to the enhancement of the public services. This conceptual framework also helps us understand how designers serve as social innovation facilitators by developing community-driven, inclusive platforms for public service delivery and engagement. The practical implications of this study provides a sustainable network, fostering a stronger sense of belonging among the citizens. By incorporating social networking features, the app facilitates communication, collaboration, and the creation of new community networks, thereby enhancing active participation and contributing to the overall social fabric of the city. The results show that digital platforms can serve as scalable instruments for participatory governance when they are created using the concepts of social innovation and co-creation. The conceptual mobile app provides a flexible and transparent framework for cooperation between corporations, colleges, citizens, and public agencies
Biodegradation in Design Process: Digital building catalog for bio-inspired design proposals
(Education and Research in Computer Aided Architectural Design in Europe (eCAADe) Conference 43rd, 2025) Ercan, İrem; Özbengi Uslu, Filiz; Kayabaş, Mehmet Ali
Through the incorporation of fungal biodegradation processes into architectural design, a novel approach to sustainability is possible, which goes beyond the selection of materials and growth processes and enables insights from natural decomposition. While biodegradable materials are increasingly studied, the potential of biodegradation itself to shape design remains largely unexplored. Although the biodegradation process is seen as the final stage of design, the existing knowledge of structural deformation in nature could be an inspiration for the design process in the early stages. This study analyzes the structural transformations of five fungal species during biodegradation in mesh-like frameworks as a basis for future research. This research involves a literature review, experimental analysis, and digital catalog development, resulting in MyCo-Design, a platform that documents species-specific biodegradation data. Structural changes such as shrinkage, curvature, stiffness reduction, and volume decrease were captured through photography and 3D scanning techniques, providing a resource for bio-inspired designs. MyCo-Design platform provides designers with information by species, structural forms, and degradation parameters to use as inspiration in the early stages of their design process. This platform features an AI-powered interface component that enables users to generate visuals based on design prompts inspired by experimental observation data. During the testing process, the platform showed potential in inspiring structural solutions based on biodegradation observation. The findings of the study highlight the potential to generate circular inspiration in the early stages of design through a tool created at the intersection of nature, humans, and artificial intelligence
Exploring Bio-Actors of the Cities through Serious Games
(SIGraDi 2024 Proceedings of the XXVIII Conference of the Iberoamerican Society of Digital Graphics, 2024) Ercan, İrem; Oguz, Kaya
This study focuses on the importance of biodiversity in protecting the urban ecosystem in urban planning. Considering cities as an ecosystem, city actors should communicate collaboratively within this ecosystem. Urban actors include not only humans but also other bio-based creatures. For the communication in the city through design, collecting information about bio-actors with their habitats, serious games can play an important role. Since serious games are useful for educating players, city inhabitants can be informed through these games. It was chosen as a method that provides a space to players for learning by entertaining. Therefore, the game 'My City Mate: Exploring Bio-actors of the City', developed on the Twine platform, offers players the opportunity to get to know the bio-actors of a fictional city environment with the visual, audio and text-based information it provides. Lastly, this research analyzes players' learning and interaction levels with this game through surveys.
Time-Varying Correlations and Volatility Spillovers Between Cryptocurrencies and Islamic Equity Indices: Indonesia, Pakistan and India
(Dumlupınar Üniversitesi Sosyal Bilimler Dergisi, 0029-01-26) Balcı, Nehir; Gürel, Beyza
This study investigates the co-movements and volatility spillover dynamics between cryptocurrencies and Islamic equity indices in Indonesia, Pakistan and India addresses the scarcity of comparative evidence for these major developing economies. The study examines volatility spillovers and dynamic correlations across markets based on return series from January 4, 2017, to January 4, 2025, employing BEKK-GARCH and DCC-GARCH models. Empirical results reveal a unidirectional transmission of volatility from cryptocurrencies to Islamic equities, except for Ethereum and Pakistan, where a weak bidirectional spillover is observed. The analysis uncovers a time-horizon dichotomy. Short-term spillovers remain limited. Dynamic correlations intensify significantly over the long run. This suggests a growing integration between cryptocurrency assets and Islamic stock markets indices. Cryptocurrencies act as diversifiers in the short run and their role as hedges weakens over the long term. This deeper integration increases the exposure of Islamic financial systems to cryptocurrency-induced risks and may affect overall financial stability. These results highlight the need for regulators and policymakers to closely monitor volatility transmission channels and enhance oversight mechanisms. A clear understanding of these dynamics is essential to mitigate the risk of systemic disruptions and ensure the resilience of Islamic financial markets amid the growing influence of digital assets
Unraveling bortezomib resistance in multiple myeloma: insights from RNA-Seq and PI3K/mTOR pathway analysis
(Journal of Biological Research - Bollettino della Società Italiana di Biologia Sperimentale, 2026-01-04) Ates, Onur; Kiraz, Yagmur
Multiple Myeloma (MM), characterized by abnormal plasma cell proliferation, lacks curative treatment due to drug resistance, notably against Bortezomib, a critical proteasome inhibitor. To elucidate resistance mechanisms, we conducted RNA sequencing on Bortezomib-sensitive and resistant RPMI-8226 MM cells, comparing them to healthy B-cells. Differential expression analysis highlighted significant alterations in immune signaling, proteasome function, and metabolism. Resistant MM cells exhibited decreased antigen-presentation genes (HLA-DRA, HLA-DPA1, CD74), indicating immune evasion. Downregulation of metabolic regulators like GLUL and MDK suggested a glycolytic metabolic shift, whereas enhanced proteasome activities and nucleocytoplasmic transport represented adaptive strategies against proteotoxic stress. Importantly, resistant cells showed notable upregulation of PRAME and FAF1 genes, as oncogenes and apoptosis-related genes linked to therapy resistance. Pathway analysis revealed enrichment in neurodegenerative disease-related pathways, suggesting common protein misfolding mechanisms in MM progression. Additionally, resistant cells displayed cross-resistance to the dual protein kinase B (AKT)/mammalian target of rapamycin (mTOR) BEZ235, with a four-fold increase in IC₅₀ values, reflecting enhanced survival signaling and metabolic flexibility. These findings underscore the multifaceted nature of Bortezomib resistance, driven by metabolic reprogramming, immune modulation, and translational regulation. Targeting these adaptive pathways through combination therapies involving proteasome inhibitors, metabolic modulators, and autophagy inhibitors may present novel strategies to overcome drug resistance in MM.
A Scalability Assessment of Biofabrics as an Alternative Architectural Construction Material
(Sociedad Iberoamericana de Gráfica Digital (SIGraDi), 2024-11-15) Gözde Damla Turhan Haskara; Filiz Özbengi Uslu; Selen Çiçek; Anıl Dinç Demirbilek
This research explores the scalability of biopolymer applications in recent biobased textile design applications for architectural construction. It particularly focuses on the transition from laboratory experimentation to architectural construction practice with the aid of computational design and digital fabrication. The research aims at harvesting spatial structures through the re-characterization processes for desired material properties. The methodology is divided into four steps: Modification of the biofabric formulation derived from bacterial cellulose (BC); tensile strength tests; computational design and digital fabrication of a catenary geometry as a scaffold; bioassembly process; and observations at different environmental conditions after the removal of the scaffold. The results have shown that the material properties, such as the tensile strength, structural integrity, high capacity of water detention, and heat insulation, differentiate bacterial cellulose-based biopolymers as circular alternatives to the current conventional architectural construction materials and processes, having us reevaluate our connection with nature through architecture.
Economic Ideas Across Borders (Building Bridges Through Football: Migration, Identity, and German Influence in Turkish Football)
(Routledge, 2025) Genç, Tolga
Exploring the cross-cultural exchange of ideas between German and Turkish scholars, policymakers, and institutions, this book sheds light on how German theories were interpreted and applied in Turkey during the nineteenth and twentieth centuries. Situating the flow of ideas within broader patterns of economic globalization, the contributors to this edited volume explore historical, economic, and ideological developments in Turkey and Germany. Within economic thought, there is a particular focus on the influence of the German Historical School in Turkish economic thought; the contributions of German refugee scholars in the 1930s, through their publications, courses they offered, and their relations with the other members of academia; and Marxian Asiatic Mode of Production debates of the 1960s. In terms of economic policy, the book also discusses agrarian populism in the 1930s, German soft power in interwar Turkey, the first Gastarbeiter Agreement and its effects, German investments in Turkey after the World War II, and the role of sports in shaping relations between Germany and Turkey. The book will be of great interest to readers in the history of economic thought, intellectual history, economic history, and the histories of Germany and Turkey more broadly.
Analyzing the Amplified Revisionist Voice of Sexton in the Turkish Translation of Live or Die
(2025) Yetkin Karakoç, Nihal
Çeviri ve Diplomasi
(2022) Yetkin Karakoç, Nihal
Rhizomic Affect & Digital Labor: Embodied Creativity in Marvel Fan Videos on YouTube
(2025) Kaya Kitınur, Sevda
Women on the Edge: Gender Representation in Mare of Easttown
(2025) Bolat, İdil; Keleş, Semra
Perceived person-group alignment and collective action intentions in environmental movements
(2025) Ergiyen, Tolga; Serap Akfırat
Mobilizing Nature-Based Solutions Through Temporary Urban Interventions: A Civic Guide to Ephemeral Landscapes
(2025) Doğu, Tuba; Hande Atmaca; Doğu, Tuba; Çetın, Hande Atmaca
The potential of permeable urban landscapes has gained increasing attention in contemporary academic scholarship on nature-based solutions (Nbs). The common thread of these solutions is related to pressing issues arising from responses to climate change caused by urban densification, necessitating innovative strategies for enhancing environmental resilience. However, these strategies often require extensive timeframes and large-scale implementation. In contrast, temporary approaches to urbanism have the potential to provide answers to these strategies by focusing on citizen-engaged, small-scale, low-cost and low-tech actions. This study engages these two planning approaches in dialogue by focusing on overlooked urban interstices—small and unnoticed impervious spaces that have significant potential to become permeable. Developing a conceptual framework, the research explores how ephemeral installations can transform these interstices into nature-based, scalable and socially engaged landscapes. Applying this framework, the study adopts prototyping as an experimental research method, structured around three phases: (1) experimentation: incorporating nature-based aggregates, (2) fabrication: forming scalable and modular tiles, and (3) dissemination: creating social value with workshops. Building over the findings of these phases, the paper concludes with a proposal for a civic urban guide that outlines all these practical strategies for activating underutilized spaces through accessible and low-maintenance interventions. The guide aims to inspire civic engagement and environmental awareness, offering a model for small-scale, bottom-up interventions in line with broader Nbs objectives. In doing so, the research proposes a comprehensive approach to urban resilience that bridges planning theories, material experimentation, and public engagement.
Towards a Sensorial Approach to Inclusive Urban Policy Making: Narrated Walks in Izmir's Cittaslow Neighborhood Program
(Pergamon-Elsevier Science Ltd, 2025) Gökçe Sanul; Doğu, Tuba; Sanul, Gokce; Dogu, Tuba
With the rise of the information society and rapid advancements in technology, policy makers increasingly adopt data-driven approaches to understand and respond to complex urban challenges. In this context, the use walking for quantitative measures have become prominent, often guiding the agenda of local governments through metrics for urban policy making. However, this paper argues that sensory experiences captured through qualitative walking methods offer a valuable source of data for urban policy making. Incorporating sensory data presents an inclusive understanding of both physical and socio-cultural dynamics of urban space. Drawing on the methodology and findings of the walking method used in the Cittaslow Metropolis research project based in Izmir, Turkey, the paper demonstrates how spatially evoked sensorial experiences can inform and enrich inclusive urban policy development. The paper introduces a novel 'sensorial approach to urban policy making', locating sensorial experiences as a central analytical category that emphasize the integration of embodied, place-based knowledge. While critiquing the overreliance on standard quantitative methods, this paper also articulates the need for further interdisciplinary research combining qualitative and quantitative techniques of sensorial analysis, thereby supporting more inclusive urban policy making.
Jury Casting in Sing! China: Validity of Group Celebrity Persona in the Study of Comradery Capital Across China
(Bloomsbury Publishing Plc., 2025) Kaya Kitınur, Sevda; Kitinur, S.K.
Taking root in cracks: Junk ecologies of the urban
(2025) Doğu, Tuba; Melis Baloğlu

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