WoS İndeksli Yayınlar / WoS Indexed Publications

Permanent URI for this collectionhttps://hdl.handle.net/11413/6359

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4-Hydroxyquinolin-2(1H)-One Isolated in Cryogenic Argon and Xenon Matrices: Tautomers and Photochemistry
(Elsevier, 2024) Secrieru, A.; Lopes, S.; Nikitin, T.; Cristiano, Maria L. S.; FAUSTO, RUI
4-Hydroxyquinolin-2(1H)-one (4HQ2O) was synthesized, isolated in cryogenic matrices (argon and xenon), and studied by infrared spectroscopy. Quantum chemical calculations carried out at the DFT(B3LYP)/6-311++G (3df,3pd) level of theory were used to determine the conformational and tautomeric properties of the molecule. Two tautomeric forms were identified in the as-deposited matrices with the help of the theoretical data. To investigate the photochemistry of the compound, in situ broadband ultraviolet (lambda > 283 nm) irradiation of the asdeposited argon matrix was performed. This irradiation led to the generation of an additional tautomer, together with the products of fragmentation of the heterocyclic ring of the molecule, specifically isocyanic acid and carbon monoxide. Photoproducts such as 1,3-dihydro-2H-indol-2-one and cyclohepta-1,2,4,6-tetraene were also observed in the photolyzed argon matrix. A comprehensive assignment of the infrared spectra of all the species observed experimentally is presented.
Open Access
A Bayesian Deep Neural Network Approach to Seven-Point Thermal Sensation Perception
(IEEE-Inst Electrical Electronics Engineers Inc., 2022) ÇAKIR, MUSTAFA; AKBULUT, AKHAN
To create and maintain comfortable indoor environments, predicting occupant thermal sensation is an important goal for architects, engineers, and facility managers. The link between thermal comfort, productivity, and health is common knowledge, and researchers have developed many state-of-the-art thermal-sensation models from dozens of research projects over the last 50 years. In addition to these, the use of intelligent data-analysis techniques, such as black-box artificial neural networks (ANNs), is receiving research attention with the aim of designing building thermal-behavior models from collected data. With the convergence of the internet of things (IoT), cloud computing, and artificial intelligence (AI), smart buildings now protect us and keep us comfortable while saving energy and cutting emissions. These types of smart buildings play a vital role in building smart cities of the future. The aim of this study is to help facility managers predict the thermal sensation of the occupants under the given circumstances. To achieve this, we applied a data-driven approach to predict the thermal sensation of occupants of an indoor environment using previously collected data. Our main contribution is to design and evaluate a deep neural network (DNN) for predicting thermal sensations with a high degree of accuracy regardless of building type, climate zone, or a building's heating and/or ventilation methods. We used the second version of the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Global Thermal Comfort Database to train our model. The hyperparameter-tuning process of the proposed model is optimized using the Bayesian strategy and predicts the thermal sensation of occupants with 78% accuracy, which is much higher than the traditional predicted mean vote (PMV) model and the other shallow and deep networks compared.
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Adaptive Direction-Guided Structure Tensor Total Variation
(Elsevier, 2021) Kamasak, Mustafa E.; TÜREYEN, EZGİ DEMİRCAN
Direction-guided structure tensor total variation (DSTV) is a recently proposed regularization term that aims at increasing the sensitivity of the structure tensor total variation (STV) to the changes towards a predetermined direction. Despite of the plausible results obtained on the uni-directional images, the DSTV model is not applicable to the arbitrary (multi-directional and/or partly nondirectional) images. In this study, we build a two-stage denoising framework that brings adaptivity to the DSTV based denoising. We design a DSTV-like alternative to STV, which encodes the first-order information within a local neighborhood under the guidance of spatially varying directional descriptors (i.e., orientation and the dose of anisotropy). In order to estimate those descriptors, we propose an efficient preprocessor that captures the local geometry based on the structure tensor. Through the extensive experiments, we demonstrate how beneficial the involvement of the directional information in STV is, by comparing the proposed method with the state-of-the-art analysis-based denoising models, both in terms of quality and computational efficiency.
Open Access
Adoption of Lean Construction and AI/IoT Technologies in Iran's Public Construction Sector: A Mixed-Methods Approach Using Fuzzy Logic
(Multidisciplinary Digital Publishing Institute (MDPI), 2024) UĞURAL, MEHMET NURETTİN; AGHILI, SEYEDARASH; Burgan, Halil Ibrahim
The construction sector in Iran faces substantial inefficiencies, including high material wastage, posing environmental and economic risks. This study investigated the adoption of Lean Construction (LC) practices and AI/IoT technologies in Iran's public construction sector using a mixed-methods approach. This research examined the organizational, technical, and infrastructural factors across four key provinces-Tehran, Isfahan, Khorasan Razavi, and Fars-and employed fuzzy logic to address the uncertainties in adoption decisions. Data from 28 key stakeholder interviews were analyzed using Python 3.9, with libraries such as Pandas 1.3.3, NumPy 1.21.2, and skfuzzy 0.4.2 for the statistical analysis and NVivo 12 for the thematic coding. The analysis revealed that organizational readiness and leadership support were the critical drivers of adoption, particularly in Isfahan and Khorasan Razavi, which exhibited the highest adoption likelihood scores (0.5000). Tehran and Fars showed slightly lower scores due to regulatory barriers and financial limitations. The findings highlight the need for targeted leadership training, regulatory reforms, and infrastructure investments to accelerate the adoption of these technologies. This study aligned with the Sustainable Development Goals (SDG 9: Industry, Innovation, and Infrastructure and SDG 11: Sustainable Cities and Communities) by offering practical recommendations for advancing sustainable practices in Iran's construction sector. The insights provided have broader implications for other developing economies facing similar challenges, contributing to global efforts toward sustainable development.
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After the Protest: Istanbul Park Forums and People's Engagement in Political Action
(Routledge Journals, Taylor & Francis Ltd., 2022) RAMAZANOĞULLARI, HANDE
This article presents an overview of the Istanbul park forums that emerged in parallel with the Gezi events - social protest movements that took place in summer 2013. Despite the criticism that Gezi events were short-lived, impulsive, and ineffectual I argue that they have a long-lasting influence on democratic consciousness and new forms of political action. Istanbul park forums, the street and urban squares have become an important link between those who wish to transform the qualities of both democracy and the regime at large with efforts to create influence over local and national policy-making processes through engagement in political action. Drawing from the political theory of Hannah Arendt, this study assigns the capacities of 'deed and speech' to redefine 'politics'. Analyzing the politics of the park forum process through the lens and concepts of Arendt's political theory suggests an alternative way of evaluating the eventual dissolution of the Gezi events: rather than suffering from the inability to organize themselves within the conventional format of party politics, I show that the Gezi community deliberately created a new manner of engagement through political action, and thereby cast its influence as a historic landmark in the future of Turkish politics.
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Agent-Based Modelling of Interstellar Contacts Using Rumour Spread Models
(Cambridge University Press, 2020) Uyar, Tevfik; Özel, Mehmet Emin
Some stochastic model of rumours asserts that even an advanced communication network does not guarantee every agent hears certain news because they predict that rumour spreaders convert to stifflers when contacted with an informed agent. In this study, we adapted two rumour spread models to interstellar communication by developing an agent-based model (ABM) for exploring the issue more rigorously. We enhanced the spread models by adding two additional parameters called conversion probability and stop-criterion, which represent the eagerness and persistency of civilizations to establish new contacts. Results of the ABM under several settings suggest that limited SETI searches lead to undiscovered civilizations. Earth may be one of these undiscovered civilizations although an advanced communication network might already be set up. Hence, we speculate that rumour spread models can propose another solution to Fermi's Paradox.
Open Access
An Analysis of Differential Bundle Functioning in Multidimensional Tests Using the SIBTEST Procedure
(Jate-Int Journal Assessment Tools Education, 2022) ÖZDOĞAN, DİDEM; Kelecioğlu, Hülya
This study aims to analyze the differential bundle functioning in multi-dimensional tests with a specific purpose to detect this effect through differentiating the location of the item with dif in the test, the correlation between the dimensions, the sample size, and the ratio of reference to focal group size. The first 10 items of the test that is comprised of 30 items were acknowledged as the bundle. The data in line with the parameters were generated via sas program as two categories (1-0) and multidimensional through an extended 2pl model. Differential bundle functioning was detected via the sibtest procedure. The results of the study were interpreted according to the criteria of the power rate and the type I error. When the results were reviewed, the analysis of the bundle revealed that the more the correlation between the two dimensions increased, relatively the less the power rates became. It was observed that the power rates, which were obtained according to two different sample sizes in the study, increased as the sample size increased. Another result as to the sibtest's power for detecting dif was the highest when the ratio of reference to focal group size was equal. According to the results of the type I error rate, the error rate was observed to be relatively decreasing as the correlation between the dimensions increased and it was observed to be increasing as the sample size increased. Also, the highest error rate was obtained when the ratio of the samples was equal.
Open Access
An Efficient Generation and Security Analysis of Substitution Box Using Fingerprint Patterns
(IEEE, 2020) ŞENGEL, ÖZNUR; Aydın, Muhammed Ali; Sertbaş, Ahmet
Information and its security have attracted the research community in recent years with increasing usage of mobile applications. Mobile devices have different security options in data transmission such as reading some biometric values. The keystone of the modern block and stream ciphers is the use of a substitution box (s-box) that obscures correlation between plaintext and ciphertext. In this study, we proposed a novel s-box generation algorithm by using the fingerprint pattern of the person who transfers information to the target. We generated several s-boxes by using bifurcation and ridge ending features of the fingerprint. Proposed s-boxes are compared with several known s-boxes over nonlinearity, bijectiveness, strict avalanche criterion, bit independence criterion, linear probability, and differential probability. Along with these properties, we analyzed confidence interval and randomness properties of new s-boxes as well. Also, the execution time of the proposed s-box generation algorithm is calculated and examined. The results of the cryptographic properties have shown that the proposed s-boxes by using ridge ending of the fingerprint performs better. The performances analysis show that the proposed s-box has satisfactory results according to the results of chaotic-based s-boxes. On the other hand, the fingerprint s-boxes are much better than the existing biometric s-boxes according to the s-box security metrics. The results have shown that the execution time of the proposed s-box generation algorithm is more minimum than the existing biometric s-box generation algorithms. Resulting from applying fingerprint biometric data to generate an s-box, such a successful algorithm is promising to be used in mobile devices.
Open Access
An Evaluation of Liminality in Nadine Gordimer's July's People
(2020-03) KABAK, MURAT
Set during a civil war in the apartheid South Africa, Nadine Gordimer's July's People is centred around the relationship between the Smales family and their former servant July. As the communal ties disintegrate in the novel, three objects play a vital role in our understanding of the characters. For the purposes of this study, these symbols not only help us to reveal the nature of spatial-temporal dislocation but also reveal Gordimer's commentary on the apartheid South Africa. This study aims to contribute the existing scholarship by focusing on the liminal/in-between experience in July's People through analyzing the novel's preoccupation with subject-object relationship.
Open Access
Analysis of a Prefabricated Vertical Drain (PVD) Soil Improvement Project
(Turkish Chamber Civil Engineers, 2022) MERT, AHMET CAN; AREL, ERSİN; ÖNALP, AKIN
A settlement analysis has been carried out for several sectors of a rail station yard improved with prefabricated vertical drains (PVD) in Istanbul, that exhibited prolonged consolidation beyond the predicted values in certain sectors of the treated zone. Final settlement and End of Primary (EOP) settlement times have been estimated theoretically as well as using the Asaoka graphical procedure. The compliance of settlement-time curves with in-situ measurements and Asaoka solution has been investigated. A geotechnical model was developed for finite element and three-dimensional consolidation analyses. The settlement curves obtained by varying horizontal-vertical permeability coefficient ratio (k(h)/k(v)) and in-situ measurements have been compared, and k(h)/k(v) values corresponding to 90% degree of consolidation has been computed for all sectors. The effect of drain spacing (S-drain) as well as drain length (L-drain) on the rate of consolidation have been evaluated for each sector, keeping the specified ratios constant. The times corresponding to 95% degree of consolidation (t(95)) have been calculated using the theoretical solution and compared to in-situ measurements. Calculated t(95)'s has also been compared to their estimated values by varying the spacing (S-drain) and the length (L-drain). Additionally, the required intervals of S-drain and L-drain have been obtained corresponding to the calculated t(95) times. The analyses suggest that the main reason for prolonged consolidation was the horizontal to vertical permeability coefficient ratio. According to the analysis results, PVD implementation was not efficient in clays having k(h)/k(v) of approximately unity. The main conclusion of this study was to discover the necessity for optimizing the variables in any such project. The efficacy of the works can be significantly enhanced if simultaneous evaluation of the parameters S-drain and L-drain and the permeability ratio k(h)/k(v) is carried out prior to field work. Otherwise, "accidents" may emerge as found out in this project.
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Analytic Functions With Conic Domains Associated With Certain Generalized q-integral Operator
(Korean Mathematical Society, 2023) Ahuja, Om P.; ÇETİNKAYA, ASENA; Jain, Naveen Kumar
In this paper, we define a new subclass of k-uniformly starlike functions of order-gamma (0 <= gamma < 1) by using certain generalized q integral operator. We explore geometric interpretation of the functions in this class by connecting it with conic domains. We also investigate q sufficient coefficient condition, q-Fekete-Szego inequalities, q-Bieberbach De Branges type coefficient estimates and radius problem for functions in this class. We conclude this paper by introducing an analogous subclass of k-uniformly convex functions of order-gamma by using the generalized q-integral operator. We omit the results for this new class because they can be directly translated from the corresponding results of our main class.
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An Analytical Approach to Machine Layout Design at a High-Pressure Die Casting Manufacturer
(Springer-Verlag Singapore Pte Ltd., 2022) EMİR, OĞUZ; AKTİN, AYŞE TÜLİN
Sahin Metal was founded in 1975 on a 7500 m(2) area in.Istanbul to supply high-pressure aluminum casting parts to a variety of industries, especially automotive manufacturers. 64 different products are produced with various routings through 14 workstations in the plant. Being a Tier 2 company, these products are then sent to Tier 1 firms and finally reach the leading vehicle manufacturers. Nowadays, increasing competition, changing customer demands, and quality targets bring the necessity of restructuring internal processes. In this regard, Sahin Metal plans to rearrange the existing machine layout to minimize the distance traveled between departments by taking into account the material flow. This study aims to determine an efficient machine layout design by implementing analytical approaches. The study is started by visiting the production facility and meeting with the company's engineers to determine the project roadmap. Following that, the data collection process is initiated, and ABC analysis is performed to define product classes. After this identification, two approaches are utilized simultaneously. The Hollier method is employed to find a logical machine arrangement. In addition, a mathematical model based on the Quadratic Assignment Problem (QAP) is developed to obtain the optimum machine layout. The developed integer nonlinear model is solved by CONOPT using GAMS software under various scenarios. Finally, these results are compared with the existing system, and a convenient layout design is proposed to the company.
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Analyzing the Wastewater Treatment Facility Location/Network Design Problem via System Dynamics: Antalya, Turkey Case
(Academic Press Ltd. - Elsevier Science Ltd., 2022) DEMİREL, DUYGUN FATİH; Gönül-Sezer, Eylül Damla; Pehlivan, Seyda Alperen
Wastewater treatment facility location selection and network design issues have become attractive topics in the field of wastewater management due to increasing human population, resource scarcity, environmental concerns, and rise of necessity for sustainable solutions for future policy designs. Especially in areas where the demand for wastewater treatment increases dramatically over the years because of reasons such as high migration levels, rapid industrialization, and tourism activities, the problem turns out to be more critical and dynamic. The existing studies try to deal with the issue through mathematical modeling approaches based on optimization perspectives, which require significant computational effort. In this study, an alternative approach based on system dynamics (SD) method is proposed to examine the complex dynamic and nonlinear structure of waste-water treatment facility location selection and network design problems. The proposed SD simulation model is designed for a densely populated industrial and tourism spot, the city of Antalya, located on the Mediterranean coast of Turkey. The model is capable of determining where and when to build a new wastewater treatment facility as well as generating the generic wastewater network structure to be built for the five districts situated in the city center based on cost issues for 2015-2040 period. In addition, the impacts of demand level changes for wastewater treatment due to population variations are analyzed via several scenarios to help decision makers to develop sustainable and cost-efficient management policies. Although SD is a frequently utilized approach in the water/wastewater management arena, to the best of our knowledge, this study is the first attempt to examine the complex and dynamic nature of wastewater treatment facility location selection and network design problems through SD approach.
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Anxiolytic-Like Effects of Extremely Low Frequency Electric Field in Stressed Rats: Involvement of 5-HT2C Receptors
(Taylor & Francis Ltd., 2022) Kantar, Deniz; Acun, Alev Duygu; AFŞAR, EBRU; Yargıçoğlu, Piraye
Background Possible modulatory effects of noninvasive brain stimulation have gained interest recently. In our study, the effect of low frequency electric fields (LF-EF) on stress-induced electrophysiological, behavioral changes and the possible involvement of serotonergic 5-HT2C receptors were investigated. Materials and methods A total of eight groups including the control groups were formed by applying LF-EF with or without a 5-HT2C receptor agonist to naive or acute stress exposed rats to demonstrate the effects of LF-EF. LF-EF administration at 10 kV/m was started 30 min before acute stress application and lasted for 1 h in total. Anxiety levels and social interaction were evaluated using the elevated plus maze test and social interaction test, respectively. Auditory evoked potentials (AEP) were recorded by using ascending loudness paradigms. Loudness dependence AEP (LDAEP) was calculated by using amplitude values to analyze serotonergic transmission. Serotonin and glucocorticoid levels were measured in the frontal cortex and hippocampus. Results It was observed that the applied LF-EF reduced the anxiety behavior, and attenuated the LDAEP responses in stress and/or 5-HT2C receptor agonist applied groups. In parallel, an increase in serotonin levels and a decrease in glucocorticoid levels were observed. However, LF-EF exposure was ineffective in impaired social interaction. Conclusions Our findings show that 10 kV/m LF-EF administration may modulate the neural network and physiological responses associated with mild acute stress. 5-HT2C receptor dependent functions are thought to play a role in the anxiolytic effect of LF-EF.
Open Access
Are There Any Changes in Mothers' Attitudes? Analysis of the Impact of the Covid-19 Quarantine on Child-Rearing Attitudes
(Pergamon-Elsevier Science Ltd., 2022) TORAN, MEHMET; Özden, Bülent
The present study aims to examine the impact of the time spent by mothers at home with their children during the quarantine period that was implemented due to the COVID-19 pandemic on the mothers' child-rearing attitudes, taking into consideration some variables and the experiences of mothers. The study was designed using embedded mixed design, in which qualitative and quantitative research methods were used together. The quantitative research group consisted of 673 mothers and the qualitative research group consisted of 16 mothers. The research data was gathered online using the Lime Survey platform, and the interviews with the mothers were also held online. Demographic information form, the Child Rearing Attitude Scale, and a semi-structured interview form were used as data collection tools. Moderator variable analysis was used for the quantitative research data and descriptive analysis was used for the qualitative research data in support of the quantitative data. The findings revealed that the mothers' child-rearing attitudes changed depending on the variables concerning the children; however, the quarantine period instituted due to COVID-19 had an impact on the mothers' child-rearing attitudes depending on the variables of age and number of children. The qualitative findings obtained from the interviews supported the quantitative findings. However, it was revealed that the mothers' attitudes towards their children underwent changes during the quarantine period under COVID-19.
Open Access
Are Time Management and Cyberloafing Related? Investigating Employees’ Attitudes
(2020) Ötken, A. Begüm; Bayram, Ayhan; Göl Beşer, Senem; KAYA, ÇİĞDEM; 246912; 108211; 18140
Time is a critical commodity both for individuals and companies because it is not possible to substitute or purchase it. The concept of time management, therefore, attracted the attention of both academicians and practitioners. Companies started to question behaviour of employees using their companies’ Internet access for non-work-related purposes during work hours. These activities constitute an unproductive use of time and detract employees from completing their work demands. In this framework, the purpose of this study is to understand whether time management and cyberloafing are related. Data were collected from 300 employees working in Istanbul, Turkey. Results show that the time wasters dimension negatively explained the variance in serious cyberloafing. Results also show that time planning and time attitude dimensions positively explained the variance in minor cyberloafing. Understanding the relationship between time management and cyberloafing provides fruitful results for companies and individuals in terms of productivity and achieving goals at work.
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Arteriovenous Fistula Self-Care Behaviors in Patients Receiving Hemodialysis Treatment: Association With Health Literacy and Self-Care Agency
(Sage Publications Ltd., 2022) Bülbül, Elif; Ayvaz, Meryem Yıldız; Yeni, Tuğba; TÜREN, SEVDA; Efil, Sevda
Background: Arteriovenous fistula-related self-care behaviors, self-care agency and health literacy are important for vascular access patency, which is vital in the continuation of hemodialysis treatment. The purpose of this study was to determine the arteriovenous fistula-related self-care behaviors of patients receiving chronic hemodialysis treatment and the relationship between these behaviors and their health literacy and self-care agency levels. Methods: In this descriptive correlational study, the data were collected from 216 chronic hemodialysis patients. Results: The rate of the patients who had good self-care behaviors levels was 83.96%. The sociodemographic variables that were significantly related to AVF-related self-care behaviors were education, employment status and age. It was found that the patients who had had AVF for a longer time had better self-care behaviors regarding their management of symptoms and findings (p < 0.05). As the self-care agency of the patients (r = 0.612, p < 0.001) and their health literacy (r = 0.421, p < 0.001) increased, their AVF-related self-care behaviors also increased. Conclusion: Age, education status, health literacy and self-care agency were identified to affect AVF-related self-care behaviors.
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Assessment of Nutritional Status, Body Composition and Blood Biochemical Parameters of Patients Following Sleeve Gastrectomy: 6 Months Follow Up
(Elsevier, 2021) BATAR, NAZLI; Demir, Halime Pulat; Bayram, Hatice Merve
Background and aims: Today, Sleeve gastrectomy (SG) has recently become the most common bariatric procedure among various bariatric surgical procedures due to its advantages. The aim of this study is to investigate nutritional status, body composition and biochemical parameters following SG. Methods: This was a prospective study, the subjects were patients who underwent SG at a special obesity clinic in Istanbul, Turkey, between 01.05.2017 and 01.11.2017. The mean body mass index (BMI) of the participants was 42.15 +/- 4.84 kg/m(2) for men and 41.44 +/- 4.34 kg/m(2) for women, preoperatively. Nutritional status, some anthropometric measurements and blood sampling were taken at each visit. Data were collected and analyzed for the present study at the following periods: pre-operation (pre-op), 1 month, 3 months and 6 months after surgery. Results: A total of 47 SG patients (20 men, 27 women) were evaluated. The mean BMI was 30.23 +/- 3.56 kg/m(2) for men and 30.35 +/- 4.36 kg/m(2) for women after 6 months and the amount of excess weight loss (EWL) increased in the 3 months (p <.001). Mean energy, fiber, vitamin A, vitamin C, vitamin B-1, niacin, vitamin B-12, folate, calcium, magnesium, iron, zinc, phosphorus and iodine were above the Dietary Reference Intake (DRI) recommendations. A significant association was found between protein intake and fat free mass loss in both genders after SG at 6 months (p <.05). Conclusion: Nutrition deficiencies are common for patients after SG. Therefore, it is important to routinely monitor these patients with a professional team. (C) 2021 European Society for Clinical Nutrition and Metabolism. Published by Elsevier Ltd. All rights reserved.
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Assessment of Psychometric Characteristics of the Coronavirus Anxiety Scale in Patients with Preexisting Psychiatric Disorders
(Taylor & Francis, 2022) Karahamet, Elif; Angın, Ülkem; Yılmaz, Onat; DENİZ, DERYA; Konuk, Numan
This study aimed to evaluate the psychometric characteristics of the Turkish version of the CAS in a Turkish psychiatric outpatient setting. A total of 198 patients with a preexisting psychiatric disorder completed the CAS scale. The scale's validity and reliability were evaluated using convergent and concurrent validity, internal consistency, exploratory and confirmatory factor analyses, and ROC analysis. The Turkish version of CAS might help physicians assess the COVID-19 associated anxiety in patients with psychiatric comorbidities.
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Assessment of Seismic Demand and Damping of a Reinforced Concrete Building After CFRP Jacketing of Columns
(Techno-Press, 2022) KOÇAK, PINAR İNCİ; Göksu, Çağier; Töre, Erkan; Binbir, Ergun; Ateş, Ali Osman; İlki, Alper
While the lateral confinement provided by an FRP jacket to a concrete column is passive in nature, confinement is activated when the concrete expands due to additional compression stresses or significant shear deformations. This characteristic of FRP jacketing theoretically leads to similar initial stiffness properties of FRP retrofitted buildings as the buildings without retrofit. In the current study, to validate this theoretical assumption, the initial stiffness characteristics, and thus, the potential seismic demands were investigated through forced vibration tests on two identical full-scale substandard reinforced concrete buildings with or without FRP retrofit. Power spectral density functions obtained using the acceleration response data captured through forced vibration tests were used to estimate the modal characteristics of these buildings. The test results clearly showed that the natural frequencies and the mode shapes of the buildings are quite similar. Since the seismic demand is controlled by the fundamental vibration modes, it is confirmed using vibration-based full-scale tests that the seismic demands of RC buildings remain unchanged after CFRP jacketing of columns. Furthermore, the damping characteristics were also found similar for both structures.

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