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Intelligent Control of a New High Voltage Gain Interleaved DC-DC Converter for Fuel Cell Applications
Get PDFAs important elements of the hydrogen economy, fuel cells (FCs) require high step-up DC-DC converters. To this end, a new high voltage gain interleaved DC-DC converter benefiting from expandable quadratic-boost and switched-capacitor networks is proposed in this paper. A switching model shows that the proposed converter reaches a voltage gain of about 10, semiconductor voltage stresses are half of the output voltage or less, and current stresses are cut in half when compared to the non-interleaved version. Besides, according to a dynamic simulation study, the newly proposed single-input fuzzy-logic controller-based control method allows less than half the settling time and 5% less voltage overshoot than the current mode control; moreover, it attains a perfect current sharing while voltage mode control fails by having a current unbalance factor of up to 0.33. Finally, an average model demonstrates the accomplished operation of the offered system under an office block power demand
The relationship between secondary traumatic stress and mindfulness levels of nurses working in intensive care units: A City Hospital example
Get PDFBu çalışmada yoğun bakım ünitelerinde çalışmakta olan hemşirelerin ikincil travmatik stresleri ve mindfulness düzeyleri arasındaki ilişkinin belirlenmesi amaçlanmıştır. Tanımlayıcı ve ilişkisel tipte planlanan bu araştırma Aralık 2023-Haziran 2024 tarihleri arasında İstanbul Başakşehir Çam ve Sakura Şehir Hastanesi Yoğun Bakım Ünitelerinde en az 6 aydır çalışan ve çalışmaya katılmayı kabul eden 265 hemşire ile yürütülmüştür. Veriler "Kişisel Bilgi Formu", "İkincil Travmatik Stres Ölçeği", "Bilinçli Farkındalık Ölçeği" aracılığıyla toplanmıştır. Verilerin analizi SPSS (Statistical Package for Social Sciences) for Windows 25.0 programı kullanılarak yapılmıştır. Çalışmaya katılan hemşirelerin %53.6'sı 29 yaş altı, %46.4'ü 29 yaş üzeri, %44.9'u 3 yıl ve altında yoğun bakımda çalışmakta olup, %38.1'i 4-5 yıl, %17'si ise 6 yıl ve üzerinde yoğun bakımda çalıştığı görülmüştür. Bilinçli farkındalık ölçeği ile duygusal ihlal (r=-0.464, p<.05), kaçınma (r=-0.506, p<.05), uyarılmışlık boyutları (r=-0.468, p<.05) ile ikincil travmatik stres ölçeği arasında (r=-0.519, p<.05) istatistiksel olarak anlamlı ve negatif düzeyde bir ilişki olduğu tespit edilmiştir. Regresyon analizinde, Bilinçli farkındalıktaki 1 birimlik artışın duygusal ihlal üzerinde 0.400'lük (β=-0.400), kaçınma üzerinde 0.458'lik (β=-0.458), uyarılmışlık üzerinde 0.454'lük (β=-0.454) ve ikincil travmatik stres üzerinde 0.440'lık (β=-0.440) azalışa sebep olduğu görülmüştür. Bu çalışmada ulaşılan sonuçlara göre yoğun bakım ünitelerinde çalışmakta olan hemşirelerin ikincil travmatik stres düzeyleri ile mindfulness düzeyleri arasında anlamlı ve negatif düzeyde bir ilişki bulunmuştur. Bu araştırmanın sonuçlarına dayanarak, hemşirelerin ikincil travmatik stresle etkili şekilde başa çıkabilmeleri için mindfulness becerilerinin geliştirilmesi, bu bağlamda mindfulness temelli eğitim programlarının uygulanması ve etkinliklerini inceleyen deneysel araştırmaların sayısının artırılması önerilmektedir.This study aimed to determine the relationship between secondary traumatic stress and mindfulness levels among nurses working in intensive care units. Designed as a descriptive and correlational study, the research was conducted between December 2023 and June 2024 at the Başakşehir Çam and Sakura City Hospital in Istanbul. A total of 265 nurses who had been working in intensive care units for at least six months and consented to participate were included. Data were collected using the "Personal Information Form," the "Secondary Traumatic Stress Scale," and the "Mindfulness Attention Awareness Scale." Data analysis was performed using the SPSS (Statistical Package for Social Sciences) for Windows 25.0 software. Among the participating nurses, 53.6% were under the age of 29, 46.4% were 29 or older, 44.9% had been working in intensive care for three years or less, 38.1% for 4–5 years, and 17% for six years or more. Statistically significant and negative correlations were found between the mindfulness scale and the intrusion (r = -0.464, p < .05), the avoidance (r = -0.506, p < .05), the arousal subdimension (r = -0.468, p < .05), and the overall secondary traumatic stress scale (r = -0.519, p < .05). Regression analysis indicated that a one-unit increase in mindfulness resulted in decreases of 0.400 units (β = -0.400) in intrusion, 0.458 units (β = -0.458) in avoidance, 0.454 units (β = -0.454) in arousal, and 0.440 units (β = -0.440) in secondary traumatic stress. The findings of this study demonstrated a significant negative relationship between secondary traumatic stress levels and mindfulness levels among nurses working in intensive care units. Based on these results, it is recommended to enhance nurses' mindfulness skills to effectively cope with secondary traumatic stress. Implementing mindfulness-based training programs and conducting further experimental studies to evaluate their effectiveness are also suggested
The effect of leadership style on employees & organizational silence and cyberloafing behavior in tourism enterprises
Get PDFAraştırmanın temel amacı, liderlik tarzlarının çalışanların örgütsel sessizlik ve sanal kaytarma davranışı üzerindeki etkisini belirlemektir. Ayrıca çalışmanın alt amacı olarak çalışanların demografik özellikleri doğrultusunda liderlik tarzlarını algılama düzeyleri, örgütsel sessizlik ve sanal kaytarma davranışları arasında farklılık olup olmadığını belirlemektir. Araştırma İstanbul'da bulunan 5 yıldızlı otel işletmelerinde çalışan 390 katılımcı ile gerçekleştirilmiştir. Nicel araştırma yönteminin kullanıldığı araştırmada verilerin toplanması için anket tekniğinden yararlanılmıştır. Araştırmada liderlik tarzları ölçeği, örgütsel sessizlik ve sanal kaytarma ölçekleri uygulanmıştır. Elde edilen veriler SPSS 27 paket programı ile analiz edilmiştir. Araştırmada elde edilen bulgular liderlik tarzlarının, etkileşimci liderlik ve tam serbestlik tanıyan liderlik boyutları ile örgütsel sessizlik ölçeğinin bireysel sessizlik boyutu arasında istatistiksel olarak anlamlı bir etkinin olduğu ortaya çıkarılmıştır. Ayrıca yapılan analizler sonucu elde edilen bulgular liderlik tarzlarının dönüşümcü liderlik ve etkileşimci liderlik boyutları ile örgütsel sessizlik ölçeğinin ilişkisel sessizlik boyutu arasında istatistiksel olarak anlamlı bir etkinin olduğunu ortaya koymuştur. Tam serbestlik tanıyan liderlik ile sanal kaytarma ölçeğinin majör kaytarma ve minör kaytarma boyutu arasında istatistiksel olarak anlamlı bir etkinin olduğu tespit edilmiştir. Buna karşın sanal kaytarma ölçeğinin majör kaytarma ve minör kaytarma boyutları ile liderlik tarzları ölçeğinin dönüşümcü liderlik, etkileşimci liderlik boyutları arasında istatistiksel olarak anlamlı bir etkinin olmadığı ortaya konulmuştur. Anahtar Sözcükler: Liderlik Tarzları, Örgütsel Sessizlik, Sanal KaytarmaThe main purpose of the study is to determine the effect of leadership styles on employees' organizational silence and cyberloafing behavior. Additionally, as a secondary objective, the study aims to determine whether there are differences in employees' perceptions of leadership styles, organizational silence, and cyberloafing behavior based on their demographic characteristics. The research was conducted with 390 participants working in five-star hotel enterprises in Istanbul. A quantitative research method was used, and data were collected through a survey technique. In the study, the leadership styles scale, organizational silence scale, and cyberloafing scale were applied. The data obtained were analyzed using the SPSS 27 software package. The findings of the study revealed that there is a statistically significant effect between leadership styles, specifically the transactional leadership and laissez-faire leadership dimensions, and the individual silence dimension of the organizational silence scale. Additionally, the findings from the analyses demonstrated a statistically significant effect between the transformational leadership and transactional leadership dimensions and the relational silence dimension of the organizational silence scale. It was determined that there is a statistically significant effect between laissez-faire leadership and both the major cyberloafing and minor cyberloafing dimensions of the cyberloafing scale. However, no statistically significant effect was found between the major and minor cyberloafing dimensions of the cyberloafing scale and the transformational and transactional leadership dimensions of the leadership styles scale
Factors affecting compliance in CPAP device usage for obstructive sleep apnea: a mixed-methods study integrating quantitative and qualitative findings
Get PDFBackgroundThis study aims to identify novel factors influencing adherence to Continuous Positive Airway Pressure (CPAP) devices, the primary treatment for obstructive sleep apnea (OSA), and to compile the most comprehensive list of variables in the literature.MethodsA mixed-methods approach was adopted, analyzing patient records from a sleep center between 2018 and July 1, 2023. Quantitative data were obtained from surveys administered to 449 patients, while qualitative data were collected through in-depth interviews with 30 patients and document reviews of 449 records. Analyses were conducted using FACTORY Analysis, SmartPLS, IBM SPSS, and MAXQDA software.ResultsThe combined analysis of quantitative and qualitative findings identified previously unreported variables affecting CPAP adherence. A comprehensive list of influencing factors was developed, spanning device/accessory-related, psychosocial, environmental, individual, regional, and political domains. Eight novel variables were uncovered, including barriers such as fear of lightning/thunder, fear of earthquakes, relocation, religious practices, air pollution, and long hair, as well as facilitators like the use of automatic devices and rural residency. These findings indicate that existing theories and models are insufficient to fully explain CPAP adherence, highlighting the complexity of the process.ConclusionThis study highlights the complexity of CPAP adherence and calls for new theoretical models. It highlights the importance of geographical, cultural, and religious influences, advocating for further research to address these gaps and improve patient adherence strategies.Clinical trial numberNot applicabl
Cognitive Vehicular Network Based Accident Information System for Sustainable Traffic
Get PDFVehicle Ad Hoc Networks emerge as a new research area. Vehicle ad hoc networks (VANETs) are widely used in intelligent transportation systems to reduce traffic congestion as well as to ensure safety and security by using vehicle-to-vehicle(V2 V) and vehicle-to-roadside(V2R) unit communications. Many people are seriously injured or even die in traffic accidents due to human errors, including driver errors (e.g. driver inattention and distraction, careless driving and poor driving skills) and errors of other road users (e.g. traffic violations). According to T & Uuml;& Idot;K data, the fact that the ratio of driver fault to total fault has never fallen below 88% for decades shows that this problem has become a chronic problem and needs to be thought about and solution(s) produced. The main factor that increases the possibility of drivers making mistakes is the roads they navigate with the help of navigation that they have not experienced before. At this point, a driver traveling on a road he has not experienced before should be warned as he approaches the point where many accidents have occurred on the relevant route before. By warning the driver who is approaching accident black spots, where many accidents have occurred in the past, more attention can be paid to points with high accident risk. Radius information of accident black spots can be estimated using a fuzzy-based model. As a result, the aim is to minimize accidents caused by driver error. This is done with the Accident Information System (KAB & Idot;S) application
A persistent opponent in the late Ottoman period: Abdurrezzak Effendi from Baghdad and the Intikad newspaper
Get PDFStimulating Pro-Environmental Behavior Through Social Media Marketing in Environmental Organizations
Get PDFEnvironmental organizations have increasingly utilized social media platforms to highlight issues related to climate change and environmental challenges, raise public awareness, foster engagement on environmental matters, cultivate a positive corporate image, and promote environmentally sustainable consumption practices. However, there is a lack of empirical evidence regarding the influence of these organizations' social media marketing strategies on their followers. The study aims to investigate the effect of environmental organizations’ social media marketing activities on brand image, online word-of-mouth communications, and the pro-environmental behaviors of followers. A quantitative approach was used in the research, and data were gathered through online questionnaires from 529 users who actively follow ten well-known environmental organizations on Facebook, Instagram, Twitter, and LinkedIn in Türkiye. The theoretical model and hypotheses were tested with Structural Equation Modeling (SEM). The social media marketing components of environmental organizations were defined as awareness, interaction, timeliness, customization, and advertising. As a result of the analysis, it was revealed that the social media marketing components of environmental organizations' awareness, timeliness, and interaction have a positive effect on the pro-environmental behaviors of the followers. At the same time, these components have a significant effect on brand image and online word-of-mouth in environmental organizations. In addition, it has been demonstrated that brand image and online word-of-mouth in environmental organizations significantly affect on the pro-environmental behaviors of the followers. The findings suggest that social media serves as an effective platform for environmental organizations to enhance their brand image and promote pro-environmental behavior. However, these organizations face challenges regarding the effectiveness of advertisements and the personalization of communication on these platforms. © 2025 Elsevier B.V., All rights reserved
EXPLORING THE EFFECTIVENESS OF PRE-TRAINED TRANSFORMER MODELS FOR TURKISH QUESTION ANSWERING
Get PDFRecent advancements in Natural Language Processing (NLP) and Artificial Intelligence (AI) have been propelled by the emergence of Transformer-based Large Language Models (LLMs), which have demonstrated outstanding performance across various tasks, including Question Answering (QA). However, the adoption and performance of these models in low-resource and morphologically rich languages like Turkish remain underexplored. This study addresses this gap by systematically evaluating several state-of-the-art Transformer-based LLMs on a curated, gold-standard Turkish QA dataset. The models evaluated include BERTurk, XLM-RoBERTa, ELECTRA-Turkish, DistilBERT, and T5-Small, with a focus on their ability to handle the unique linguistic challenges posed by Turkish. The experimental results indicate that the BERTurk model outperforms other models, achieving an F1-score of 0.8144, an Exact Match of 0.6351, and a BLEU score of 0.4035. The study highlights the importance of language-specific pre-training and the need for further research to improve the performance of LLMs in low-resource languages. The findings provide valuable insights for future efforts in enhancing Turkish NLP resources and advancing QA systems in underrepresented linguistic contexts
OPTIMIZATION OF WELDING PARAMETERS OF ELECTRICAL RESISTANCE SPOT WELDED 6082-7075 ALUMINIUM JOINTS USING THE TAGUCHI METHOD
Get PDFIn this study, aluminium alloys of AA6082 and AA7075 series were welded with resistance spot welding. Effects of welding current intensity, welding time, and electrode pressure on the tensile strength and microstructure were examined, and their optimized values were determined using the Taguchi method. While performing optimization, the L24 orthogonal array was used with the Taguchi method. With this array, the signal/noise (S/N) ratio became the determining factor in controlling the optimization results. Comparing the experimental procedures and analysis results, the results obtained from the real application and Taguchi analysis were found out to be similar
The relationship between self-efficacy, psychological well-being, dyspnea, and fatigue in patients with chronic obstructive pulmonary disease: A structural equation model
Get PDFBu çalışmada KOAH hastalarının; öz yeterlik, psikolojik iyi oluş, dispne ve yorgunluk arasındaki ilişkiyi bulmak amaçlanmıştır. Araştırma tanımlayıcı ve ilişki arayıcı tiptedir. Örneklemi bir Sağlık Uygulama ve Araştırma Merkezi'nde KOAH tanısı ile yatmakta olan 194 hasta oluşturmuştur. Veriler Kişisel Bilgi Formu, KOAH Öz- etkililik ölçeği, Psikolojik İyi Oluş ölçeği, Dispne-12 ölçeği, KOAH ve Astım Yorgunluk ölçeği kullanılarak toplanmıştır. Yapısal eşitlik modeline göre; dispne ve yorgunluk arasında anlamlı, pozitif yönlü (p<0.05), öz yeterliğin dispne üzerinde anlamlı negatif yönlü (p<0.05), öz yeterliğin psikolojik iyi oluş üzerinde anlamlı pozitif yönlü (p<0.05) ilişkisi olduğu bulunmuştur. Öz yeterliğin dispne üzerindeki etkisinde psikolojik iyi oluşun aracı rolünün istatistiksel olarak anlamlı ve öz yeterliğin yorgunluk üzerindeki etkisinde psikolojik iyi oluşun aracı rolünün istatistiksel olarak anlamlı olduğu bulunmuştur (p<0.05). Çalışmada yer alan modelde psikolojik iyi oluş, öz yeterlik, dispne ve yorgunluk arasındaki ilişkide aracı rolü üstlenmiştir. Bu bağlamda KOAH hastaları ile çalışırken dispne ve yorgunluk şikayetlerinin azaltılması için psikolojik iyi oluşa dair hemşirelik müdahalelerinin kullanılarak, holistik bakıma önem verilmesi önerilebilir. Anahtar Sözcükler: Dispne, KOAH, Öz yeterlik, Psikolojik iyi oluş, YorgunlukThe aim of this study was to find the relationship between self-efficacy, psychological well-being, dyspnea and fatigue in COPD patients. The study is descriptive and correlational. The sample consisted of 194 patients hospitalized with COPD in the Health Application and Research Center. Data were collected using Personal Information Form, COPD Self-Efficacy Scale, Psychological Well-Being Scale, Dyspnea-12 Scale, COPD and Asthma Fatigue Scale. According to the structural equation model, there was a significant positive relationship between dyspnea and fatigue (p<0.05), a significant negative relationship between self-efficacy and dyspnea (p<0.05) and a significant positive relationship between self-efficacy and psychological well-being (p<0.05). It was found that the mediating role of psychological well-being in the effect of self-efficacy on dyspnea was statistically significant, and the mediating role of psychological well-being in the effect of self-efficacy on fatigue was statistically significant (p<0.05). In the model in the study, psychological well-being was found to play a mediating role in the relationship between self-efficacy, dyspnea and fatigue. In this context, it may be recommended to give importance to holistic care by using nursing interventions related to psychological well-being to reduce dyspnea and fatigue complaints while working with COPD patients