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Article Citation - Scopus: 9Multipath Exploitation in Emitter Localization for Irregular Terrains(Czech Technical University, 2019) Dalveren,Y.; Kara,A.Electronic Support Measures (ESM) systems have many operational challenges while locating radar emitter's position around irregular terrains such as islands due to multipath scattering. To overcome these challenges, this paper addresses exploiting multipath scattering in passive localization of radar emitters around irregular terrains. The idea is based on the use of multipath scattered signals as virtual sensor through Geographical Information System (GIS). In this way, it is presented that single receiver (ESM receiver) passive localization can be achieved for radar emitters. The study is initiated with estimating candidate multipath scattering centers over irregular terrain. To do this, ESM receivers' Angle of Arrival (AOA) and Time of Arrival (TOA) information are required for directly received radar pulses along with multipath scattered pulses. The problem then turns out to be multiple-sensor localization problem for which Time Difference of Arrival (TDOA)-based techniques can easily be applied. However, there is high degree of uncertainty in location of candidate multipath scattering centers as the multipath scattering involves diffuse components over irregular terrain. Apparently, this causes large localization errors in TDOA. To reduce this error, a reliability based weighting method is proposed. Simulation results regarding with a simplified 3D model are also presented. © 2019 RADIOENGINEERING.Article Citation - WoS: 11Citation - Scopus: 20The Taylor Series Method and Trapezoidal Rule on Time Scales(Elsevier Science inc, 2020) Georgiev, Svetlin G.; Erhan, Inci M.The Taylor series method for initial value problems associated with dynamic equations of first order on time scales with delta differentiable graininess function is introduced. The trapezoidal rule for the same types of problems is derived and applied to specific examples. Numerical results are presented and discussed. (c) 2020 Elsevier Inc. All rights reserved.Article Citation - WoS: 11Citation - Scopus: 11Higher Rates of Cefiderocol Resistance Among Ndm Producing klebsiella Bloodstream Isolates Applying Eucast Over Clsi Breakpoints(Taylor & Francis Ltd, 2023) Isler, Burcu; Vatansever, Cansel; Ozer, Berna; Cinar, Gule; Aslan, Abdullah Tarik; Falconer, Caitlin; Harris, Patrick N. A.BackgroundCefiderocol is generally active against carbapenem-resistant Klebsiella spp. (CRK) with higher MICs against metallo-beta-lactamase producers. There is a variation in cefiderocol interpretive criteria determined by EUCAST and CLSI. Our objective was to test CRK isolates against cefiderocol and compare cefiderocol susceptibilities using EUCAST and CLSI interpretive criteria.MethodsA unique collection (n = 254) of mainly OXA-48-like- or NDM-producing CRK bloodstream isolates were tested against cefiderocol with disc diffusion (Mast Diagnostics, UK). Beta-lactam resistance genes and multilocus sequence types were identified using bioinformatics analyses on complete bacterial genomes.ResultsMedian cefiderocol inhibition zone diameter was 24 mm (interquartile range [IQR] 24-26 mm) for all isolates and 18 mm (IQR 15-21 mm) for NDM producers. We observed significant variability between cefiderocol susceptibilities using EUCAST and CLSI breakpoints, such that 26% and 2% of all isolates, and 81% and 12% of the NDM producers were resistant to cefiderocol using EUCAST and CLSI interpretive criteria, respectively.ConclusionsCefiderocol resistance rates among NDM producers are high using EUCAST criteria. Breakpoint variability may have significant implications on patient outcomes. Until more clinical outcome data are available, we suggest using EUCAST interpretive criteria for cefiderocol susceptibility testing.Article Citation - WoS: 11Citation - Scopus: 15A Study on the Performance Evaluation of Wavelet Decomposition in Transient-Based Radio Frequency Fingerprinting of Bluetooth Devices(Wiley, 2022) Almashaqbeh, Hemam; Dalveren, Yaser; Kara, AliRadio frequency fingerprinting (RFF) is used as a physical-layer security method to provide security in wireless networks. Basically, it exploits the distinctive features (fingerprints) extracted from the physical waveforms emitted from radio devices in the network. One of the major challenges in RFF is to create robust features forming the fingerprints of radio devices. Here, dual-tree complex wavelet transform (DT-CWT) provides an accurate way of extracting those robust features. However, its performance on the RFF of Bluetooth transients which fall into narrowband signaling has not been reported yet. Therefore, this study examines the performance of DT-CWT features on the use of transient-based RFF of Bluetooth devices. Initially, experimentally collected Bluetooth transients from different smartphones are decomposed by DT-CWT. Then, the characteristics and statistics of the wavelet domain signal are exploited to create robust features. Next, the support vector machine (SVM) is used to classify the smartphones. The classification accuracy is demonstrated by varying channel signal-to-noise ratio (SNR) and the size of transient duration. Results show that reasonable accuracy can be achieved (lower bound of 88%) even with short transient duration (1024 samples) at low SNRs (0-5 dB).Article Citation - WoS: 5Citation - Scopus: 6Photoelectronic and Electrical Properties of Tl2ingas4< Layered Crystals(Pergamon-elsevier Science Ltd, 2007) Qasrawi, A. F.; Gasanly, N. M.Tl2InGaS4 layered crystals are studied through the dark electrical conductivity, space charge limited current and illumination- and temperature-dependent photoconductivity measurements in the temperature regions of 220-350 K, 300-400 K and 200-350 K, respectively. The space charge limited current measurements revealed the existence of a single discrete trapping level located at 0.44 eV. The dark electrical conductivity showed the existence of two energy levels of 0.32 eV and 0.60 eV being dominant above and below 300 K, respectively. The photoconductivity measurements reflected the existence of two other energy levels located at 0.28 eV and 0.19 eV at high and low temperatures, respectively. The photocurrent is observed to increase with increasing temperature up to a maximum temperature of 330 K. The illumination dependence of photoconductivity is found to exhibit supralinear recombination in all the studied temperature ranges. The change in recombination mechanism is attributed to exchange in the behavior of sensitizing and recombination centers. (C) 2006 Elsevier Ltd. All rights reserved.Article KAHRAMANMARAŞ ÇOCUK ABALARINDA NAZARLIK(2016) Kuru, Songül; Kırkıncıoğlu, Zeynepİnanç sistemine bağlı olarak gelişen toplumlarda, sembolik ifadeler, kişisellikten öte, toplumca kabul gören ortak değerleri yansıtmışlardır. Semboller, bir arada yaşayan insanların ortak özelliklerini, inançlarını, göreneklerini temsil ederek ve onların diğerlerinden ayrılmasını sağlamaktadır. Yaşam, doğum, üreme, korunma vb. gibi insanlığın ortak döngüleri üzerine kurgulanan semboller, önceleri mağara duvarlarında ve mitolojilerde yer alırken, daha sonra dokuma ve desenleme tekniklerinin geliştirilmesiyle, bu görevi dokumalar üstlenmiştir. Dokuma ürünlerine uygulanan desenlerle; doğum, bereket, beslenme, ölüm, korunma ile ilgili birçok anlam yüklemiştir. Korunma ile ilgili motiflerin başında nazar, nazarlıklar gelmektedir. Anadolu'da önemli inançlardan birisi de nazar inancıdır. Arapça bakış anlamına gelen nazar, Türkçede de aynı manada kullanılır. Çalışmanın amacı; Türk kültüründe önemli yeri olan nazar konusu hakkında bilgi vermek ve Kahramanmaraş çocuk abalarında bulunan nazar ve koruma ile ilgili motifler ve süslemeleri fotoğraf ve çizimlerle irdeleyerek değerlendirmektir. Betimsel yöntemin kullanıldığı araştırmada, Anadolu gelenek ve göreneklerine göre çocukları nazardan korumayla ilgili inançlardan bahsedilmiştir. Kahramanmaraş çocuk abalarında geleneksel öğeler içeren nazara karşı koruyucu motifler, çeşitli malzeme ve objelerden yapılan süslemeler ve ifade ettiği sembolik anlamlar yorumlanarak öneriler getirilmiştirArticle Citation - Scopus: 3Complete Characterization of a Class of Permutation Trinomials in Characteristic Five(Springer, 2024) Grassl,M.; Özbudak,F.; Özkaya,B.; Temür,B.G.In this paper, we address an open problem posed by Bai and Xia in [2]. We study polynomials of the form f(x)=x4q+1+λ1x5q+λ2xq+4 over the finite field F5k, which are not quasi-multiplicative equivalent to any of the known permutation polynomials in the literature. We find necessary and sufficient conditions on λ1,λ2∈F5k so that f(x) is a permutation monomial, binomial, or trinomial of F52k. © The Author(s) 2024.Article Citation - WoS: 15Contractive Multivalued Maps in Terms of q-functions on Complete Quasimetric Spaces(Springer international Publishing Ag, 2014) Karapinar, Erdal; Romaguera, Salvador; Tirado, PedroIn this paper we prove the existence of a fixed point for multivalued maps satisfying a contraction condition in terms of Q-functions, and via Bianchini-Grandolfi gauge functions, for complete T-0-quasipseudometric spaces. Our results extend, improve, and generalize some recent results in the literature. We present some examples to validate and illustrate our results.Article Sürdürülebilir Girişimci Ağına Kavramsal ve Makroekonomik Yaklaşım:\ramerika Özelinde Bir Endeks Çalışması(2021) Benli, Hande EminLiteratürde, girişimci ağı kavramının salt “ağ/network” kavramı ile ilişkilendirilmesinden kaynaklı\rboşluk kavramın somut şekilde anlaşılmasını güçleştirmektedir. Bu çalışmanın amacı, “sürdürülebilir\rgirişimci ağı” kavramını literatüre katmak için tanımsal bir çerçeve çizmek, bu kavramı formüller\rkullanarak ölçülebilir hale getirmek, örnek ülke özelinde endeks oluşturmak ve kavramın\rmakroekonomi ile ilişkisini ortaya koymaktır. Yöntemsel olarak sürdürülebilir girişimci ağı girişimcilik\rkültürü, girişimci ağı ve evrimsel döngü unsurları çerçevesinde tanımlanmaktadır. Teorik arka planda\rliteratürde yer alan Network Teorisi ve Ürün Yaşam Döngüsü Yaklaşımlarından esinlenilmiştir.\rSürdürülebilir girişimci ağı tanımsal çerçeveden yola çıkarak dört evrede matematiksel formüllerle\rölçülmüştür. Elde edilen göstergeler alt endekse dönüştürülmüş ve HDI metodolojisi kullanılarak\rSürdürülebilir Girişimci Ağı Endeksi (SGAE) elde edilmiştir. Çoklu doğrusal bağlantı problemini\rortadan kaldırmak amacıyla SGAE hem aritmetik ortalama (ağırlıklandırılmamış- AO) hem de Temel\rBileşenler Analizi (ağırlıklandırılmış- PCA) yöntemleriyle hesaplanmıştır. 0-1 aralığında hesaplanan\rendeks değerlerine göre 1980-2014 dönemi içerisinde sürdürülebilir girişimci ağı endeksinde ağırlıklı\rolarak istikrar gözlenmiştir. En yüksek düzeyde olduğu yıl 0,73’lük oranla 1997 yılı olmuştur. 1980 yılı\rise sürdürülebilir girişimci ağının 0.27’lik oranla en düşük olduğu yıldır. Sürdürülebilir girişimci ağının\rmakroekonomi ile olan ilişkisi literatürden faydalanarak teorik bir çerçevede açıklanmıştır. Kavramın\rmakroekonomiyle olan ilişkisi dört evreden oluşan kurumsal etki aracılığı ile açık şekilde\rkurulabilmiştir.Article Citation - WoS: 15Fixed Point Results for Various Α-Admissible Contractive Mappings on Metric-Like Spaces(Hindawi Ltd, 2014) Al-Mezel, Saleh A.; Chen, Chi-Ming; Karapinar, Erdal; Rakocevic, VladimirWe establish some fixed point theorems for alpha-admissible mappings in the context of metric-like space via various auxiliary functions. In particular, we prove the existence of a fixed point of the generalized Meir-Keeler type alpha-phi-contractive self-mapping.. defined on a metric- like space X. The given results generalize, improve, and unify several fixed point theorems for the generalized cyclic contractive mappings that have appeared recently in the literature.
