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Investigation Procedure for the Diagnosis of Historical Minarets: Inclined Minaret of Sivas Ulu Cami (Mosque)
No full textThe inclined minaret of Sivas Ulu Cami (Mosque) from the 13th century Danishmend Period is one of the most invaluable architectural heritages in Turkey. The extent of inclination of the minaret towards the North-West direction, the seismicity of the region, and structural damages that occurred in time have emphasized the need for comprehensive structural and geotechnical investigations. Accordingly, a rehabilitation project is currently going on under the coordination of the General Directorate of Foundations of Turkey. Within the scope of the project, first, a series of field surveys have been conducted to obtain the current features of the minaret including the characteristics of the structural system, damages, deviation from the vertical axis, ground conditions and foundation details. In addition to that, a monitoring system including inclinometers, linear potentiometers and accelerometers has been mounted for tracking the evolution of deformations and damages in time under environmental influences and extracting the dynamic properties of the minaret. Findings from the field survey and monitoring system were used for constructing an analytical model of the structural system of the minaret. Then nonlinear time history analyses were conducted under various strong ground motion records to estimate the seismic performance of the minaret when subjected to earthquakes of different characteristics. The results showed that the tensile stresses that occurred due to seismic actions exceeded the tensile strength of the brick masonry at the region of the transition segment and the cylindrical body (top level of the boot). © Tongji University Press 2024.Directorate General of Foundations; Ministry of Culture and Tourism of Turkey; Rise Engineering & Consultancy Compan
Impact of the Covid-19 Market Turmoil on Investor Behavior: a Panel Var Study of Bank Stocks in Borsa Istanbul
No full textEkinci, Cumhur/0000-0002-0475-2272Assuming that investors can be foreign or local, do high-frequency trading (HFT) or not, and submit orders through a bank-owned or non-bank-owned broker, we associated trades to various investors. Then, building a panel vector autoregressive model, we analyzed the dynamic relation of these investors with returns and among each other before and during the COVID-19 market crash. Results show that investor groups have influence on each other. Their net purchases also interact with returns. Moreover, during the turmoil caused by the pandemic, except foreign investors not involved in HFT, the response of any investor group (retail/institutional, domestic investors doing HFT and those not doing HFT, and foreign investors doing HFT) significantly altered. This shows that the interrelation among investor groups is dynamic and sensitive to market conditions.Istanbul Technical University; ITU Finance LabWe acknowledge the assistance of Mehmet Bodur and the data support by ITU Finance Lab
A Wearable Touch-Activated Device Integrated with Hollow Microneedles for Continuous Sampling and Sensing of Dermal Interstitial Fluid (Adv. Mater. 2/2024)
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A Cost- and Energy-Efficient Sram Design Based on a New 5 I-P Majority Gate in Qca Nanotechnology
No full textMisra, Neeraj Kumar/0000-0002-7907-0276; Ahmadpour, Seyed-Sajad/0000-0003-2462-8030Quantum-dot Cellular Automata (QCA) is a revolutionary paradigm in the Nano-scale VLSI market with the potential to replace the traditional Complementary Metal Oxide Semiconductor system. To demonstrate its usefulness, this article provides a QCA-based innovation structure comprising a 5-input (i-p) Majority Gate, which is one of the basic gates in QCA, and a Static Random Access Memory (SRAM) cell with set and reset functionalities. The suggested design, with nominal clock zones, provides a reliable, compact, efficient, and durable configuration that helps achieve the optimal size and latency while decreasing power consumption. Based on the suggested 5 i-p majority gate, the realized SRAM architecture improves energy dissipation by 33.95 %, cell count by 31.34 %, and area by 33.33 % when compared to the most recent design designs. Both the time and the cost have been decreased by 30 % and 53.95 %, respectively
X-Ray Spectroscopy of the Dwarf Nova Z Chamaeleontis in Quiescence and Outburst Using the Xmm-Newton Observatory
No full textWe present X-ray spectroscopy of the SU UMa-type dwarf nova Z Chamaeleontis using the European Photon Imaging Camera and reflection grating spectrometer (RGS) instruments on board the XMM-Newton observatory. The quiescent system can be modeled by collisional equilibrium (CIE) or nonequilibrium plasma models, yielding a kT of 8.2-13.0 keV at a luminosity of (5.0-6.0) x 10(30) erg s(-1). The spectra yield better chi(nu)2 using partially covering absorbers of cold and/or photoionized nature. The ionized absorber has an equivalent N-H = (3.4-5.9) x 10(22) cm(-2) and a log(xi) = 3.5-3.7 with a (50-60)% covering fraction when the VNEI model (XSPEC) is used. The line diagnosis in quiescence shows no resonance lines, with only the forbidden lines of Ne, Mg, and Si detected. The H-like C, O, Ne, and Mg are detected. The strongest line is O viii, with (2.7-4.6) x 10(-14) erg s(-1) cm(-2). The quiescent X-ray-emitting plasma is not collisional and not in ionization equilibrium, which is consistent with hot ADAF-like accretion flows. The line diagnosis in the outburst shows He-like O and Ne, with intercombination lines being the strongest, along with weaker resonance lines. This indicates the plasma is more collisional and denser, but not yet in CIE, revealing ionization timescales of (0.97-1.4) x 10(11) s cm(-3). The R ratios in the outburst yield electron densities of (7-90) x 10(11) cm(-3) and the G ratios yield electron temperatures of (2-3) x 10(6) K. The outburst luminosity is (1.4-2.5) x 10(30) erg s(-1). The flow is inhomogeneous in density. All detected lines are narrow, with widths limited by the resolution of RGS, yielding Keplerian rotational velocities <1000 km s(-1). This is too low for boundary layers, consistent with the nature of ADAF-like hot flows.Scientific Research Projects Coordination Unit of Istanbul University [40017]; ESA Member States; NASAThe authors thank M. Mendez and J. P. Lasota for useful discussions and/or comments on the manuscript. S.B. acknowledges a grant from the Scientific Research Projects Coordination Unit of Istanbul University through BAP Project No. 40017. This research is based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. This work has made use of data and software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC) maintained by NASA/GSFC.Science Citation Index Expande
Mathematical Foundations and Implementation of Coniks Key Transparency
No full textMOLLAKUQE, Elissa/0000-0003-0508-105XThis research paper explores the CONIKS key management system's security and efficiency, a system designed to ensure transparency and privacy in cryptographic operations. We conducted a comprehensive analysis of the underlying mathematical principles, focusing on cryptographic hash functions and digital signature schemes, and their implementation in the CONIKS model. Through the use of Merkle trees, we verified the integrity of the system, while zero-knowledge proofs were utilized to ensure the confidentiality of key bindings. We conducted experimental evaluations to measure the performance of cryptographic operations like key generation, signing, and verification with varying key sizes and compared the results against theoretical expectations. Our findings demonstrate that the system performs as predicted by cryptographic theory, with only minor deviations in computational time complexities. The analysis also reveals significant trade-offs between security and efficiency, particularly when larger key sizes are used. These results confirm that the CONIKS system offers a robust framework for secure and efficient key management, highlighting its potential for real-world applications in secure communication systems.European Union in the Framework of ERASMUS MUNDUS Project CyberMASC; [101082683]This research was suppored partially by the European Union in the Framework of ERASMUS MUNDUS Project CyberMASC, (Project#101082683) (https://cybermacs.eu/ accessed on: 12 August 2024).Science Citation Index Expande
Foreign Land Acquisition in Turkey: Neocolonial Tendencies or Neoliberal Economic Growth?
No full text2008 Finansal krizinden sonra, ''toprak kapma'' olarak da bilinen ''yabancı arazi edini-mi''olgusu tüm dünyada benzeri görülmemiş bir şekilde artmıştır. Küresel Güney ülkele-rinin topraklarının özellikle Afrika'da büyük oranlarda ele geçirilmesinden sonra bu eğili-min son zamanlarda gelişmekte olan ülkelere de yayıldığı görülmüştür. Türkiye hem yatı-rımcı hem de hedef ülke olması nedeniyle arazi kapma trendinde karmaşık bir görünüme sahip ülkelerden biridir. Son zamanlarda Türkiye'de başta tarım arazileri olmak üzere ya-bancı toprak ediniminin hızla artması, Türkiye kamuoyunda bazı tartışmaların kapısını aralamıştır. Türkiye'nin tarım topraklarındaki bu yabancı yatırımcılar kimler ve bu yaban-cılara toprak satışı neokolonyalizm mi yoksa neoliberal bir ekonomik kalkınma fırsatı mı? Bu soruları cevaplamak amacıyla Türkiye'deki 11 tarımsal yatırım şirketi ile yarı yapılan-dırılmış görüşmeler yapılmıştır. Elde edilen sonuçlara göre, Türkiye'deki yabancı arazi alımlarında yatırımcı olarak Körfez ülkeleri en üst sıralarda yer alıyor. Bu toprak edinimle-rinin arkasında Körfez ülkelerinin 2008 sonrası yaşanan gıda krizi nedeniyle gıda güvenli-ğini sağlama çabaları yer almaktadır. Öte yandan, Türkiye'de yabancıların toprak edinme-sinin neo-sömürgeci eğilimler taşıdığı ve aynı zamanda neoliberal ekonomik kalkınma için bir fırsat olabileceği gözlemlenmiştir. Bu durum, Türkiye'nin kendi topraklarındaki yaban-cı toprak ediniminde bir çıkmazda olduğunu göstermektedir. Bu koşullarda çıkış kapısı, tarım sektörüne uygun, doğru ve etkin yasal prosedür ve politikaların oluşturulmasıdır.After 2008 Financial crisis, ''foreign land acquisition (FLAs)''phenomenon which is also known ''land grabbing'' has unprecented accelerated all over the world. After the acquisi-tion of the territory of the Global South countries in large proportions, especially in Afri-ca, it has been seen that this trend has recently spread to developing countries as well. Turkey is one of the countries with a complex outlook on the land grabbing trend due to the fact that it is both an investor and a target country. Recently, the rapid increase of fore-ign land acquisition, especially agricultural land, in Turkey has opened some discussions door in the Turkish public opinion. Who are the foreign investors in Turkey's agricultural land, and is the sale of land to these foreigners neocolonialism or a neoliberal economic development opportunity? Semi-structured interviews were conducted with 11 agricultural investment companies in Turkey in order to clarify those questions. According to the re-sults, the Gulf countries as investors are at top of the foreign land acquisitions in Turkey. Behind these territorial acquisitions is the effort of the Gulf countries to ensure food secu-rity due to the food crisis experienced after 2008. On the other hand, it has been observed that the acquisition of land by foreigners in Turkey carries neocolonial tendencies and may be an opportunity for neoliberal economic development at the same time. This situation indicates that Turkey is at a deadlock in the foreign land acqusition in their lands. In these circumstances, the exit door is in it is the creation of correct and effective legal procedures and policies appropriate for the agri-business sector
The Impact of Response Type on Affordance and Spatial Compatibility Effects in Human and Object Interactions
No full textSoyman, Efe/0000-0003-0192-1541; Demir, Pinar/0000-0002-9734-2677Everyday social interactions or goal-directed actions towards objects activate action plans appropriate to their affordances. The spatial compatibility of a stimulus and a response might interfere with the activation of these action plans. In the present study, we examined how framing of interactions affects the interplay between affordance and spatial compatibility effects towards humans and objects in two separate experiments. In a motor priming task designed to simultaneously assess these two effects, participants were presented with interactive hand gestures and objects with a single handle. Participants responded either with their left or right hand according to the colour mask of the stimulus, regardless of the spatial position or the affordance-related orientation of the stimulus. In Experiment 1, when responses were given by keypresses, we found independent affordance and spatial compatibility effects towards objects. Surprisingly, interactive hand gestures induced a reversed affordance effect, that is, imitative action tendencies. Changing the responses from keypresses to the performance of grasping actions in Experiment 2 drastically altered these findings, resulting in the enhancement of affordance and the elimination of spatial compatibility effects for both human and object interactions. These findings highlight the importance of contextual influences on the emergence of automatic action tendencies.We would like to thank the staff of Bahceehir University Global Online (BAUGO) for their technical assistance in the preparation of the stimulus set.Social Science Citation Inde
Uncommon Hla Alleles Observed in a Population of Istanbul Province
No full textogret, yeliz/0000-0001-9732-5474Objective: New polymorphisms are formed in human leucocyte antigen (HLA) genes with point mutations, gene conversions, and duplication, and the diversity continues to increase. Various new HLA alleles have significant roles in transplantation, and epidemiologic and population studies. The aim of our study was to determine the status of HLA alleles in the Turkish population, which is uncommon, well-defined, and non-defined in the world population according to the international ImMunoGeneTics information system® (IMGT) database. Methods: We performed HLA-A, -B, -C, -DQB1, and DRB1 loci at the four-field resolution level, using Sanger- sequence-based typing (SBT) for 5592 healthy, unrelated bone marrow donor volunteers from Istanbul Province. The uncommon alleles were also confirmed using high-throughput next-generation sequencing (NGS). Results: Uncommon alleles were determined at five loci as follows: HLA-A*01:155, 02:66, 02:90, 02:110, 02:343, 03:82, 24:28, 24:146, 24:276, 24:356, 31:23,33:33, 68:38; HLA-B *07:240, 18:19, 35:193, 40:303, 51:69, 51:169; HLA-C*04:39, 06:40, 07:93, 12:149, 15:73; HLA-DRB1*11:149, 13:14:02 and HLA-DQB1*03:27. All alleles were arranged according to the common and well documented (CWD) 3.0.0 catalog. Conclusion: This is the first study to show uncommon alleles in our population. These reported data increase the knowledge of HLA polymorphisms in the Turkish population and provide a basis for further studies in population genetics. This information may also be useful in determining whether a matched, unrelated donor is unlikely to be found so that a mismatch strategy, an extended family search, or alternate therapy, can be pursued, thus saving time and cost for patients.Emerging Sources Citation Inde
Encounters With Isis-Affiliated Women: Radicalisation Process, Motivations, and Their Journey
No full textWomen from European countries have joined ISIS in considerable numbers, whether as perpetrators or passive attendants. Possible reasons for Western recruits have included seeking an identity, searching for excitement, and the romantic aspect of a new life. Despite the unknown numbers, many ISIS-affiliated from different nationalities are currently held in Turkish prisons. This article aims to contribute to women's radicalization and a gap in knowledge of ISIS women. Drawing on first-person 8 interviews at the Istanbul Repatriation Center in October 2020, the study indicates that the romantic aspect works as a catalyzer. The topic would be better elaborated by leaning on personal reasons. Key findings aim to demystify the assumptions of gendered radicalization. Further, discussions emerge from these findings, which have implications for methodology, theory, and policy and open prospects to generate avenues for future research.Emerging Sources Citation Inde