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Article Citation - WoS: 2Citation - Scopus: 2Performance of Ge-Sandwiched Gase Layers(Springer, 2018) Qasrawi, A. F.; Qasrawı, Atef Fayez Hasan; Abdallah, Maisam M. A.; Qasrawı, Atef Fayez Hasan; Department of Electrical & Electronics Engineering; Department of Electrical & Electronics EngineeringIn the current work, we report the effect of sandwiching Ge between two stacked layers of GaSe. The GaSe and Ge-sandwiched GaSe were subjected to x-ray diffraction, optical spectrophotometry and impedance spectroscopy measurement and analysis. The presence of a Ge layer between two layers of GaSe was observed to cause uniform deformation and increase the absorption of light by GaSe. The response of the dielectric constant to incident light was also significantly enhanced by Ge sandwiching. In addition, Drude-Lorentz modeling of the imaginary part of the dielectric constant revealed that the layer of Ge layer between GaSe layers increased the drift mobility from 30.76 cm(2)/Vs to 52.49 cm(2)/Vs. It also enhanced the plasmon frequency without altering the free carrier density. Moreover, Ge improved the band filtering features of GaSe. In particular, it enhanced the sensitivity of the impedance response to the incident signal and increased the return loss factor of GaSe when it was used as a high band pass filter.Article Citation - WoS: 2Citation - Scopus: 4State-Based Conceptual Design in Mechatronics Via Petri Nets: a Case Study for an Educational Robot(Romanian Soc Control Tech informatics, 2011) Erden, Zuhal; Mechatronics EngineeringUse of state-based models to represent artifact behaviors at conceptual design is a challenging area for design research. Conceptual design of mechatronic systems needs a multi-domain approach in which the "logical behavior" of a mechatronic design artifact is described without any physical realization. This paper presents a case study on state-based representation for the intended behavior of a non-existent robot at early conceptual level. The behavior is defined through a demonstrative scenario and represented as states and state transitions independent of any physical embodiment. Discrete Event System Specification (DEVS) and Petri Net formalism are used for the model. This representational model is first step towards the development of a virtual prototype for the logical behavior of robot design.Article Citation - WoS: 27Citation - Scopus: 28Polycrystalline Diamond End Mill Cutting Edge Design To Improve Ductile-Mode Machining of Silicon(Elsevier Science inc, 2018) Oliaei, S. N. B.; Karpat, Y.Silicon is a commonly used material in optoelectronics and micro fluidics devices. Micro mechanical milling of silicon with polycrystalline diamond (PCD) tools has the potential to produce three-dimensional surfaces with good surface finish and an increased material removal rate. PCD micro end mill geometry is known to influence process outputs yet its effect has not been studied in detail. In this study, a PCD end mill with a hexagonal geometry has been considered, and its micro cutting geometry has been modified to have a parallelogram shape featuring a large negative rake angle on the bottom of the tool. The proposed micro geometry also reduces the contact area between the tool and the work material. The proposed geometry was fabricated using wire electric discharge machining (WEDM). Ductile-to-brittle transition conditions and areal surface roughness have been investigated as a function of tool geometry and feed during micro milling of silicon. A significant improvement in material removal rate and surface roughness has been obtained compared to a commercially available PCD end mill having hexagonal geometry with flat bottom. The results show that PCD micro end mill geometry significantly affects the process outputs.Article Dance of the Corporate Veils: Shareholder Liability in the United States of America and in the Republic of Turkey(2008) Davıs, B. E. Wendy; Hızır, SerdarThe foundation of corporate law is the existence of a legal entity separate from its shareholders, thus shielding shareholders from liability for corporate obligations. Courts have rarely, and with trepidation, pierced through this corporate veil to impose liability on shareholders for corporate malfeasance. These instances have become more common in recent decades, suggesting that corporate investors and parent corporations acquiring subsidiaries need to be diligent to minimize their risk. In this article two academicians discuss the consequences of wrongdoing and mismanagement underlying the pros and cons of the systems adapted by both countries.Article Patient Safety in Healthcare: A Proposal for Ensuring the Use of Regulation-Compliant Safety Devices(Springer Heidelberg, 2025) Bayrak, TuncayMedical devices used in health care should fulfill the requirements of the technical regulations to protect patient health. Difficulties in enforcing stricter rules in the new medical device regulations may negatively affect the continuity of care. This study examines the status of manufacturers' compliance with medical device regulations, based on predefined criteria, and proposes a collaborative action plan and an approach to verify regulatory compliance. We conducted a nationwide survey comprising questions grouped by criteria to understand the status of the manufacturers in terms of compliance with the Medical Device Regulation. Four hundred sixty-seven manufacturers participated in the survey. We achieved a Cronbach's alpha of 0.77, which indicates that the survey is statistically reliable. We applied the independent samples t-test to the responses to determine significant features per question and employed factor analysis to investigate the relationships of the questions. The results of independent samples t-tests showed statistically significant differences across groups in replies to several survey items (p < 0.05), indicating that participants' opinions varied based on their demographic characteristics. We applied Exploratory Factor Analysis to introduce the relationships between the questions. The analysis revealed that manufacturers continue to face substantial challenges in acquiring sufficient knowledge and operational capability to meet MDR requirements. In light of these findings, we focused on the person responsible for regulatory compliance, who plays a central role in maintaining regulatory compliance within manufacturing organizations. We proposed an action plan at the macro level to introduce more effective action plans in cooperation with other stakeholders, including healthcare providers, and a verification approach for regulatory compliance to enhance the Person Responsible for Regulatory Compliance's competence. Manufacturers should implement effective postmarketing clinical follow-up plans involving device-oriented parameters for monitoring in the healthcare system, especially in collaboration with health professionals.Article A New Model for Customer Equity(2017) Özgen, PelinIn this study, the fundamental model of customer equity is studied and an alternative model is tested where attitudinal and behavioral customer loyalty are treated as two additional individual components of customer equity. In gathering required data, survey method is used with 377 respondents based on judgement sampling. In order to test the proposed model, a different calculation for customer equity is applied. In model testing, LISREL package program is used and structural equation modelling (SEM) is applied. Results indicate that the proposed model stating that customer equity, has two more components, namely attitudinal loyalty and behavioral loyalty, is significant at 95% confidence level, has a high goodness of fit (GFI = .93) and has an acceptable level of root mean square error (RMSEA= .07). However, results also show a correlation between value equity and brand equity terms, which can be tested with different products or sample in future studiesArticle Citation - WoS: 56Citation - Scopus: 64Development of 500 W Pem Fuel Cell Stack for Portable Power Generators(Pergamon-elsevier Science Ltd, 2015) Devrim, Yilser; Devrim, Huseyin; Eroglu, InciPolymer Electrolyte Membrane Fuel Cell (PEMFC) portable power generators are gaining importance in emergency applications. In this study, an air-cooled PEMFC stack was designed and fabricated for net 500 W power output. Gas Diffusion Electrodes (GDE's) were manufactured by ultrasonic spray coating technique. Stack design was based on electrochemical data obtained at 0.60 V was 0.5 A/cm(2) from performance tests of a single cell having the same membrane electrode assemblies (MEA) that had an active area of 100 cm(2). Graphite bipolar plates were designed and machined by serpentines type flow. The stack comprising of 24 cells was assembled with external fixing plates. The stack temperature was effectively regulated by the cooling fan based on on-off control system. A maximum power of 647 W was obtained from the stack. The PEMFC stack was stable during start-up and shutdown cycling testing for 7 days at 65 degrees C in H-2/air at a constant cell voltage. Copyright (c) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.Article Yeni-osmanlıcılığın Ekonomi Politiğinin Bir Eleştirisi: Ulusötesi Bir Hegemonya Projesinin Yükseliş ve Düşüşü(2017) Şenalp, Mehmet GürsanBu çalışma 2000'lerin ilk on yılında \"Yeni Türkiye\"nin dış ilişkilerinin ekonomi-politiğine odaklanıyor. İlk kısımda son yıllarda öne çıkan ve dış politikaya politik ekonomi perspektifinden yaklaşan bazı ana akım çalışmalar eleştirel bir değerlendirmeye tabi tutuluyor. İkinci kısımdaki kuramsal tartışma ise Marksist uluslararası (veya küresel) politik ekonomi (UPE) yazınında \"Amsterdam Okulu\" olarak bilinen çevrenin katkılarına dayanıyor. Analiz Van der Pijl'i izleyerek Yeni-Osmanlıcılığı, ulusötesi bir kontrol kavramı (hegemonya projesi) olarak sistem kaynaklı neoliberalizme belirli şartlarda eklemlenmek üzere dizayn edilen bir sınıf projesi olarak okuyor. Buna göre bölgesel düzeyde bir kontrol kavramı olarak Erdoğan ve Davutoğlu tarafından pazarlığa sürülen söz konusu stratejinin kaderi sistemik ve ulusötesi mücadeleler diyalektiğince çizilmiştir. Bu mücadeleler dünyayı yıkıma sürükleyen para ticareti yapan (money-dealing) ulusötesi sermaye fraksiyonunun küresel liderliğine karşı ve ondan yana olan sermaye fraksiyonları ve işçi sınıfları arasında; ulusal, bölgesel ve uluslararası seviyelerde bir çok devlet bağlamında aynı anda cereyan etmektedirArticle Minorities and Minority Rights in Europe(Ankara Univ European Union Research Centre, 2015) Yilmaz, GozdeEurope has been the home for various ethnic, linguistic and religious minority groups for decades and it is almost impossible to find an European country with ethnic, linguistic and religious homegeneity. Notably, conflicts in Europe after the Cold War demonstrated the importance of minority issues and minority rights for Europe. In this respect, the European organizations like the European Union or the Council of Europe actively seek to promote minority rights in Europe. Especially through the enlargement of these organizations, the promotion of minority rights widened its sphere in Europe by minority conditions required to be fulfilled by the candidate countries are for membership. However, there is still no minority standard in Europe like the one in human rights. In contrast, minority rights have still been held by sovereign European states rather than through a common platform.Article Epistemic Extraction Zones in Migration Studies: Rethinking Over-Research and Research Fatigue Among Syrian Refugees in Turkey(Wiley, 2025) Ozdemir, ZelalThis paper explores the phenomenon of over-research among Syrian refugees in Turkey, highlighting how sustained and repetitive research attention has created research saturation zones that shape both refugee experiences and knowledge production. Drawing on unstructured conversations with six Syrian refugees in Ankara, the study examines how research fatigue manifests not only as reluctance to participate but also as strategic responses through which refugees navigate frequent encounters with researchers. While existing literature has addressed research fatigue and ethics in refugee studies, less attention has been given to how academic incentives, humanitarian logics, and policy imperatives intersect to produce systematic inequalities in knowledge production. To address this gap, the paper advances the concept of epistemic extraction zones, referring to contexts where knowledge is persistently mined from marginalized communities to satisfy institutional demands with limited reciprocity or epistemic agency. This conceptual lens shifts the debate from individual withdrawal to the structural political economy of knowledge production. The analysis identifies three key dynamics. First, the emergence of research saturation zones in contexts of protracted displacement, where the same communities are repeatedly targeted for study; second, refugees' strategic yet ambivalent engagement with research, combining pragmatic hope with critical awareness of its limited effects; and third, the paradoxical consequences of over-research, where intensified attention produces epistemic extraction that narrows the circulation of knowledge and reinforces hierarchies. The article also reflects critically on the researcher's own position within these dynamics. By theorizing epistemic extraction zones, the paper contributes not only to refugee studies but also to broader sociological debates on power, inequality, and the ethics of knowledge production, highlighting the need for more reflexive and politically accountable research practices.
