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Oxford Intersections: Borders
No full textThrough its unilateral military operations between 2016 and 2020, Türkiye carved out non-contiguous territories in northern Syria, referred to in this article as the Turkish-controlled ‘safe zone’. The official reasons for these operations and the safe zone policy were cited as the maintenance of border security, the prevention of Islamic State of Iraq and Syria and Kurdish groups from expanding their territories in Syria, and the facilitation of the return of Syrian refugees. This article examines the psycho-political driving forces behind the creation of the Turkish-controlled ‘safe zone’ in northern Syria, arguing that it fulfils multifaceted functions beyond military and refugee-related objectives. By combining ontological security theory, Ejdus’ concept of ontic space, and Foucault’s notion of panopticism at the theoretical level, and by empirically analysing the zone’s creation, governance practices, and processes of institutional and cultural restructuring, this article argues that the safe zone operates as an inter-jurisdictional ontic space, fulfilling myriad material and symbolic functions. This article thus interprets the safe zone in relation to Türkiye’s status-related ontological insecurities and anxieties deriving from crises and conflicts near its contiguous territory, its desired political imaginary shaped by its neo-Ottomanist codes. Importantly, functioning as a spatial extension of Türkiye, the safe zone operates as a self-constructed buffer that mirrors the historical role Europe imposed upon Türkiye, thereby reproducing and inverting these self–other dynamics on foreign terrain. This article sheds new light on the literature by advancing a new conceptualization of the politics of spatialization beyond borders.</p
Micro- and nanoplastic pollution in urban influenced aquatic environments: Sources, pathways, and remediation strategies
No full textPlastic pollution, particularly microplastics (MPs) and nanoplastics (NPs), is increasingly threatening urban aquatic environments. These particles (25–1000 μm) originate from diverse sources and exhibit complex environmental behavior depending on their physicochemical characteristics and interactions with organic matter. Wastewater treatment plants (WWTPs), though designed to mitigate various contaminants, have demonstrated limited efficiency in removing micro and nanoplastics (MNPs), with effluent concentrations ranging from 0.2 to 180 × 10^6 MPs L−1 and removal rates 40–95 % for MPs, and lower for NPs depending on the treatment process and particle properties. This inefficiency contributes to the persistent dissemination of MNPs into rivers, lakes, and coastal areas. Moreover, ecotoxicological evidence, although limited, indicates oxidative stress and physiological impairments in fish, highlighting substantial knowledge gaps. To address these knowledge gaps, recent scientific efforts have focused on understanding the occurrence, sources, and behavior of MNPs across urban water systems, along with assessing the effectiveness of physical separation and chemical/biological degradation technologies. While methods such as coagulation, filtration, adsorption, and advanced oxidation processes show promise, each presents limitations in terms of operational cost, energy demand, and the potential generation of toxic by-products. Emerging strategies such as upcycling plastic waste and employing nature-based solutions (e.g., riparian vegetation restoration, constructed wetlands) offer complementary benefits but require further investigation and investment. This review critically summarizes current knowledge on the sources, fate, ecological impacts, and management strategies of MNPs in urban waters, identifies region-specific challenges and research gaps, and provides guidance for future monitoring, technological innovation, and policy interventions
Examination of the earthquake-induced failure mechanism of intentionally damaged rammed earth walls via shaking table experiments
No full textRammed earth structures represent sustainable construction systems that provide thermal and acoustic efficiency while utilizing locally available, environmentally friendly materials. Despite their extensive historical and contemporary applications, a significant research gap remains regarding their seismic performance. Addressing this gap, the present study introduces a novel experimental investigation on the dynamic behavior of an intentionally damaged rammed earth wall specimen. The wall was designed in an L-shaped configuration, intentionally incorporating pre-existing damage to explore the seismic performance of rammed earth structures. The experimental program employed a shaking table to subject the wall to a series of strong ground motion inputs, enabling detailed monitoring of its dynamic response. Crack patterns and failure mechanisms, displacement profiles, and acceleration histories were systematically analyzed. The results of the study can be evaluated both in terms of structures that were deliberately damaged to investigate to earthquake response and in terms of the seismic behavior of existing damaged structures. It can be stated that; by integrating intentional design modifications with experimental testing, the research contributes to the broader objective of developing sustainable, earthquake-resistant earthen construction techniques suitable for both heritage preservation and contemporary applications
KENT KİMLİĞİNİ YANSITACAK VE İKLİM DEĞİŞİKLİĞİNE UYUM SAĞLAYABİLECEK ODUNSU BİTKİLER: BURSA
No full textKENT KİMLİĞİNİ YANSITACAK VE İKLİM DEĞİŞİKLİĞİNE UYUM SAĞLAYABİLECEK ODUNSU BİTKİLER: AĞRI
No full textKENT KİMLİĞİNİ YANSITACAK VE İKLİM DEĞİŞİKLİĞİNE UYUM SAĞLAYABİLECEK ODUNSU BİTKİLER : ADANA
No full textHollow Glass Sphere Modification Effect on Mechanical Properties of Powder Bed Fusion Processed Polyamide 12 Parts
No full textThis study investigates the effects of modifying PA12 powder with a low concentration of surface-functionalized hollow glass spheres on powder characteristics and the mechanical properties of the Powder Bed Fusion–Laser Beam (PBF-LB) produced parts. A novel and scalable feedstock formulation was developed using a dissolution-precipitation method followed by dry mixing, which enabled the uniform incorporation of hollow glass spheres (Glass Beads (GBs)) while preserving the powder's flowability and thermal behavior. The powders were characterized by morphology, particle size distribution, flowability, melt behavior, and sintering window. After PBF-LB processing, the as-built parts were analyzed for part density, surface roughness, tensile, flexural, and impact properties. Results indicate that GB modification did not adversely affect powder quality but altered the mechanical performance of printed parts. 1 wt.% glass bead modified PA12 parts exhibited lower relative density and tensile strength compared to virgin PA12, but showed significantly enhanced impact resistance. This improvement is attributed to energy-absorbing mechanisms enabled by strong interfacial bonding between the glass beads and the PA12 matrix. This work introduces a novel toughening strategy for PBF-LB polymers, contributing a new material design pathway for producing lightweight, impact-resistant components in additive manufacturing for aerospace, automotive, and consumer applications using PBF-LB processes
Assessing the performance of IRI-2020 using GPS-TEC measurements in Türkiye under low solar activity conditions
No full textIonosphere is one of the major error sources for GPS since it is dispersive. TEC, which is an indicator of the state of ionosphere, can be determined by GPS. The global ionosphere models also provide TEC. IRI-2020 is one of the widely used empirical models to obtain ionospheric parameters. In this study, 92 GPS stations were analysed using GPS-TEC analysis software for three years (2019-2021). According to the results, the highest TEC values were obtained in 2021. Moreover, the largest RMSE values were generally obtained at the boundaries of the study area and the RMSE values in 2021 are larger than in other years
Design and implementation of PIλDμ controller for ROVs: Thruster modeling, controller parameter optimization, and FPGA realization
No full textRemotely operated and autonomous underwater vehicles (ROVs/AUVs) operate in a harsh environment dominated by nonlinear hydrodynamics, strong coupling, and wave–current disturbances. In most of the existing literature, surge-axis motion is still regulated by integer-order PID controllers that are tuned either heuristically or via single-scenario optimization. Such designs often exhibit limited robustness: their performance degrades significantly under severe noise, targeted wave excitation, or time-varying operational profiles. These limitations motivate the use of fractional-order control and more systematic tuning procedures. This paper investigates fractional-order PIλDμ (FOPID) controllers for surge control and compares two popular meta-heuristics, Particle Swarm Optimization (PSO) and Differential Evolution Algorithm (DEA), in comparison with classical PID. A fourth-order surge plant model is first obtained via system identification of experimental data from a BlueRobotics T200 thruster. Then, PSO and DEA are used to tune both PID and PIλDμ parameters over a multi-scenario cost function that combines step-response quality, disturbance rejection, and control effort. The resulting controllers are evaluated under four increasingly demanding tests: noiseless step tracking, severe white-noise excitation, sinusoidal “storm” disturbance, and a final scenario with time-varying set-points under the same storm condition. Across all 16 scalar performance metrics (IAE, ISE, and, ITAE over four tests), the DEA-tuned PIλDμ achieves the best value in 12 cases, consistently outperforming both PID designs and the PSO-based PIλDμ. In the most demanding final test (multi-level reference + storm), it reduces the integral time-weighted absolute error ITAE from 0.1065 (best PID) to 0.0893, i.e., by approximately 16%, while preserving competitive control effort. These results provide quantitative evidence that DEA-tuned PIλDμ offers a more robust and energy-aware solution for single-axis surge control in ROV/AUV applications
A bibliometric study on architectural education and participation (2000-2024)
No full textThis research presents a systematic literature analysis based on bibliometric data regarding the evolving key concepts of participation in the context of architectural education and environmental crises. The aim of the research is to identify potential research opportunities in the area of participatory architectural education. The Web of Science (WOS) database was opted for the bibliometric analysis process due to its access to multidisciplinary sources and compatible file formats as the analysis software. In this context, articles published between 2000 and 2024 were screened, and a comprehensive filtering was conducted in accordance with the established inclusion and exclusion criteria. As a result, a total of 256 articles were selected. The selected articles were recorded based on bibliographic data such as publication year, language, journal, title, author, institution, keywords, document type, abstract, and citation count. Vosviewer (version 1.6.20) software was used for the bibliometric analysis. The findings show that more research and documents are needed from different countries, sources and authors on participatory architectural education. This research provides a reference for future studies by revealing current concepts, prominent keywords, important authors, documents, sources, institutions, and references on participatory architectural education