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Article Citation - WoS: 19Citation - Scopus: 19A Study on the Dark and Illuminated Operation of Al/Si3< Schottky Photodiodes: Optoelectronic Insights(Springer Heidelberg, 2024) Surucu, Ozge; Yildiz, Dilber Esra; Yildirim, MuratThis work extensively investigates the operation of an Al/ Si3N4/p-Si Schottky-type photodiode under dark and varying illumination intensities. The photodiode is fabricated by employing the metal-organic chemical vapor deposition (MOCVD) method. A thorough electrical characterization is performed at room temperature, encompassing measurements of current-voltage (I-V), current-time (I-t), capacitance-time (C-t), and conductance time (G-t). The photodiode's rectification factor and reverse bias area increased under illumination. The relationship between light power density, barrier height, and diode ideality factor is found. The study also found a strong correlation between light intensity and applied voltage on series resistance (R-s) and shunt resistance (R-sh). R-s values are calculated using Cheung's functions, revealing the diode's resistance behavior. The study also examines the photodiode's photoconductivity and photoconductance, finding a non-linear relationship between photocurrent and illumination intensity, suggesting bimolecular recombination. Calculated photosensitivity (K), responsivity (R), and detectivity (D*) values show the device's light response effectiveness, but efficiency decreases at higher illumination intensities. Transient experiments indicate stable and reproducible photocurrent characteristics, revealing photogenerated charge temporal evolution. This study provides a complete understanding of the Al/Si3N4/p-Si Schottky photodiode's behavior under different illumination intensities. The findings advance optoelectronic device knowledge and enable their use in advanced technologies.Article Citation - WoS: 27Citation - Scopus: 35A Wavelet-Based Feature Set for Recognizing Pulse Repetition Interval Modulation Patterns(Tubitak Scientific & Technological Research Council Turkey, 2016) Gencol, Kenan; At, Nuray; Kara, AliThis paper presents a new feature set for the problem of recognizing pulse repetition interval (PRI) modulation patterns. The recognition is based upon the features extracted from the multiresolution decomposition of different types of PRI modulated sequences. Special emphasis is placed on the recognition of jittered and stagger type PRI sequences due to the fact that these types of PRI sequences appear predominantly in modern electronic warfare environments for some specific mission requirements and recognition of them is heavily based on histogram features. We test our method with a broad range of PRI modulation parameters. Simulation results show that the proposed feature set is highly robust and separates jittered, stagger, and other modulation patterns very well. Especially for the stagger type of PRI sequences, wavelet-based features outperform conventional histogram-based features. Advantages of the proposed feature set along with its robustness criteria are analyzed in detail.Article Citation - WoS: 13Citation - Scopus: 16An Analytic Network Process Based Risk Assessment Model for Ppp Hydropower Investments(Vilnius Gediminas Tech Univ, 2021) Akcay, Emre CanerThe number of public-private partnership (PPP) projects has gone up especially in developing countries. The risk assessment of PPP projects is essential in ensuring project success. The objective of this study is to develop an Analytic Network Process (ANP) based risk assessment model for hydropower investments, and a tool to facilitate quantification of risk ratings based on this model. The results show that the three most important risk factors that affect the overall risk rating of a PPP hydropower investment are legal risks, contractor/subcontractor risks, and operator risks. In addition, the three most important risk clusters were identified as stakeholders, government requirements, and resources, whereas market was the least important cluster. The tool that measures the risk rating of a PPP of hydropower project was tested on ten real cases, and satisfactory results were obtained in terms of its predictive capability. The contributions of this research include (1) identification of the risk factors and clusters of factors associated with PPP hydropower investments; (2) determination of the priority of each risk factor and cluster; (3) development a tool that guides the investors through the risk assessment of PPP hydropower investments.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 Citation - WoS: 6Citation - Scopus: 6Which Is Better To Predict Erectile Dysfunction and Male Sexual Function in the Context of Metabolic Syndrome: Triglyceride-Glucose Index or Visceral Adiposity Index?: a Retrospective Cross-Sectional Study(Springer, 2024) Bolat, Mustafa Suat; Bolat, Ipek Akalin; Dundar, Cihad; Asci, RamazanPurposeMany factors influence male sexual function, including metabolic disorders such as metabolic syndrome (MetS). We aimed to investigate the effects of two metabolic indices, the triglyceride-glucose (TyG) index and the visceral adiposity index (VAI), on male sexual function.MethodsA total of 400 men having sexual dysfunction were included. Anthropological data, comorbidities were recorded. Serum total testosterone, prolactin, and estradiol levels were recorded. Sex-specific VAI was calculated using the [(WC/39.68) + (1.88xMI)] x (TG/1.03) x (1.31/HDL) formula and using Ln (fasting triglycerides) x (fasting glucose)/2] formula, TyG index was calculated. Turkish-validated 15-item long-form of the International Index of Erectile Dysfunction (IIEF) questionnaire and male sexual health questionnaire (MSHQ) were used for erectile function and ejaculatory function, respectively. The ROC analysis was used to evaluate the predictive abilities of TyG and VAI cut-off values for ED risk.ResultsA higher TyG index and VAI were associated with an increased risk of ED. The presence of MetS further worsened sexual function, with lower scores in sexual satisfaction, orgasm, desire, and general satisfaction. The TyG index and VAI showed similar predictive abilities for ED. Patients with MetS had worse ejaculation quality compared to those without MetS.ConclusionsThese findings highlight the potential of the TyG index and VAI as convenient tools for predicting and assessing sexual dysfunction in men, particularly in the context of metabolic disorders. Early detection and intervention for metabolic syndrome and insulin resistance may help to mitigate their negative impact on male sexual function.Article Citation - WoS: 4Citation - Scopus: 7Clinical Characteristics of Patients With Intraocular Lens Calcification After Pars Plana Vitrectomy(Mdpi, 2023) Bopp, Silvia; Ozdemir, Huseyin Baran; Aktas, Zeynep; Khoramnia, Ramin; Yildirim, Timur M.; Schickhardt, Sonja; Ozdek, SengulAim: To determine the clinical risk factors that may increase the occurrence of intraocular lens (IOL) calcification in patients who had undergone pars plana vitrectomy (PPV). Methods: The medical records of 14 patients who underwent IOL explantation due to clinically significant IOL opacification after PPV were reviewed. The date of primary cataract surgery, technique and implanted IOL characteristics; the time, cause and technique of PPV; tamponade used; additional surgeries; the time of IOL calcification and explantation; and IOL explantation technique were investigated. Results: PPV had been performed as a combined procedure with cataract surgery in eight eyes and solely in six pseudophakic eyes. The IOL material was hydrophilic in six eyes, hydrophilic with a hydrophobic surface in seven eyes and undetermined in one eye. The endotamponades used during primary PPV were C2F6 in eight eyes, C3F8 in one eye, air in two eyes and silicone oil in three eyes. Two of three eyes underwent subsequent silicone oil removal and gas tamponade exchange. Gas in the anterior chamber was detected in six eyes after PPV or silicone oil removal. The mean interval between PPV and IOL opacification was 20.5 +/- 18.6 months. The mean BCVA in logMAR was 0.43 +/- 0.42 after PPV, which significantly decreased to 0.67 +/- 0.68 before IOL explantation for IOL opacification (p = 0.007) and increased to 0.48 +/- 0.59 after the IOL exchange (p = 0.015). Conclusions: PPV with endotamponades in pseudophakic eyes, particularly gas, seems to increase the risk for secondary IOL calcification, especially in hydrophilic IOLs. IOL exchange seems to solve this problem when clinically significant vision loss occurs.Article Citation - WoS: 172Citation - Scopus: 190Interpolative Reich-Rus Type Contractions on Partial Metric Spaces(Mdpi, 2018) Karapinar, Erdal; Agarwal, Ravi; Aydi, HassenBy giving a counter-example, we point out a gap in the paper by Karapinar (Adv. Theory Nonlinear Anal. Its Appl. 2018, 2, 85-87) where the given fixed point may be not unique and we present the corrected version. We also state the celebrated fixed point theorem of Reich-Rus-Ciric in the framework of complete partial metric spaces, by taking the interpolation theory into account. Some examples are provided where the main result in papers by Reich (Can. Math. Bull. 1971, 14, 121-124; Boll. Unione Mat. Ital. 1972, 4, 26-42 and Boll. Unione Mat. Ital. 1971, 4, 1-11.) is not applicable.Article Citation - WoS: 11Citation - Scopus: 13Challenges in Agile Software Maintenance for Local and Global Development: an Empirical Assessment(Mdpi, 2023) Almashhadani, Mohammed; Mishra, Alok; Yazici, Ali; Younas, MuhammadAgile methods have gained wide popularity recently due to their characteristics in software development. Despite the success of agile methods in the software maintenance process, several challenges have been reported. In this study, we investigate the challenges that measure the impact of agile methods in software maintenance in terms of quality factors. A survey was conducted to collect data from agile practitioners to establish their opinions about existing challenges. As a result of the statistical analysis of the data from the survey, it has been observed that there are moderately effective challenges in manageability, scalability, communication, collaboration, and transparency. Further research is required to validate software maintenance challenges in agile methods.Article Translation Movements in the Modernization Processes of Turkey and China(Department of Applied Linguistics, Translators and Interpreters, University of Antwerp, 2022) Bayraktar-Özer,Ö.The migration of knowledge between cultures is ubiquitous, whether it happens naturally on encountering communities or is consciously planned by authorities to learn from one another. As nations constantly share their scientific and philosophical knowledge with others, translation takes on a key role in the transmission of not only knowledge, but also the advancement of all aspects of the source culture. In this respect, the Qing and Ottoman empires, after experiencing military defeats, were able to recognise the progress made by certain nations as a result of the Industrial Revolution. The knowledge transfer from these industrialized countries therefore became part of the attempts by states, private institutions and reformers to catch up with these countries in the area of development through increased translation initiatives. Trends such as these subsequently continued to shape the culture-planning processes in many countries. Against this background, the present study aims to shine a light on the parallel course of translation movements in the modernization processes of China and Turkey from the mid-19th to the mid-20th century. It offers an overview of the translation movements crafted in an analogous pattern that entailed three stages of implementing translation activities in the modernization efforts of the two countries. © 2022 Artesis Hogeschool Antwerpen - Hoger Instituut voor Vertalers en Tolken. All rights reserved.Article Citation - WoS: 14Citation - Scopus: 14On Relations Between Transportation Cost Spaces and l1<(Academic Press inc Elsevier Science, 2020) Ostrovska, Sofiya; Ostrovskii, Mikhail I.The present paper deals with some structural properties of transportation cost spaces, also known as Arens-Eells spaces, Lipschitz-free spaces and Wasserstein spaces. The main results of this work are: (1) A necessary and sufficient condition on an infinite metric space M, under which the transportation cost space on M contains an isometric copy of l(1). The obtained condition is applied to answer the open questions asked by Cuth and Johanis (2017) concerning several specific metric spaces. (2) The description of the transportation cost space of a weighted finite graph G as the quotient l(1) (E(G))/Z(G), where E(G) is the edge set and Z(G) is the cycle space of G. (C) 2020 Elsevier Inc. All rights reserved.
