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Comparing the Shielding Features of Graphene and Impregnated Activated Carbon with Selected Traditional Shielding Materials For Gamma-Rays
No full textGraphene and carbon-based materials are widely used in daily life applications. The richness of optical and electronic properties has made them rapidly rising materials on the horizon of material science and condensed matter physics. Having the sheets of atoms stacked in disorganized manner makes activated carbon different from other forms of graphitic structures. The research about the shielding properties of reduced graphene oxide (RGO) and activated carbon for gamma-rays are very rare and active domain of study. Since the use of radioactive sources in different fields (nuclear industry, shielding materials, radiation biophysics and space research application, etc.) has been increasing expeditiously, the photon interactions with matter have gained importance in the world of material science technology. In this work, we review the basics of the impregnated activated carbon (AC) and RGO, as well as the relationship between the structures and the gamma shielding properties in terms of both quality and efficiency. XCom software and EGSnrc simulation code were used to obtain the theoretical values of various shielding parameters which are significantly important to be able to understand the shielding properties of AC and RGO for gamma-rays. We report the mass attenuation coefficients (?m), the half value layer (HVL), the tenth value layer (TVL), and the mean free path (MFP) values and compare them with other commonly used shielding materials like lead, borosilicate, concrete, and vermiculite. The calculated data showed that AC is very appropriate and consistent to be one of the candidates for shielding materials of gamma-rays even though the graphene is seen as inconsistent for such purpose
Current practices, potentials, challenges, future opportunities, environmental and economic assumptions for Turkiye's clean and sustainable energy policy: A comprehensive assessment
No full textIn today's world, most countries including Turkiye have met their electricity demand at a dominant rate by burning fossil-based fuels in thermal power plants. However, fossil-fuel reserves have been rapidly depleted, resulting in high volatility in these fuels' markets, as well as alarming environmental, and economic problems for the governments. In recent years, many governments have started to face these problems and have rapidly transitioned to renewable and alternative carbon-free energy sources in their electricity production variety. However, these belated steps have failed to mitigate the increment in global greenhouse gas emissions against the rapid growth of population and energy demand. In recent years, Turkiye has put a noteworthy challenge to mitigate its dominant use of fossil fuels, reducing its energy dependence, sustaining its economic development, and mitigating the carbon footprint. From this point of view, it is witnessed that many power plants have been established, many of them are currently under construction, especially to produce more electricity in a sus-tainable way. Accordingly, the present study aims to comprehensively discuss Turkiye's energy production policy, energy potential and reserves, challenges, future opportunities, and the impacts of the energy sector on the economic and environmental issues for the country. In this framework, it is well-noticed that the country's future energy production policy has been reasonably changed in order to achieve positive economic and envi-ronmental outcomes in the medium and long term
BANKA RİSKLERİNİN TÜREV FİNANSAL ARAÇLARLA YÖNETİMİ
No full textFinansal piyasaların genişlemesi ve serbestleşmesi, finansal hizmet verirken bankaların karşı karşıya kaldıkları risklerini de artırmıştır. Bankalar, bu süreçte, risklerindeki artışları türev finansal araç kullanımı ile yönetmeye çalışmıştır. Çalışmada, Türk bankacılık sektörü için piyasa riski, operasyonel risk ve kredi riskinin türev finansal araç kullanımına etkisi test edilmiş ve böylelikle söz konusu risklerin türevler yardımı ile ne ölçüde yönetildiğinin belirlenmesi amaçlanmıştır. Sınamada, Bankacılık Düzenleme ve Denetleme Kurumundan temin edilen, 2016:M01-2022:M10 dönemine ait aylık veriler kullanılmıştır. Serilerin durağanlık sınaması için Augmented Dickey–Fuller ve Philips-Perron birim kök testlerinden faydalanılmıştır. Uzun ve kısa dönem etkilerinin tahmini için ise Gecikmesi Dağıtılmış Otoregresif (Autoregressive Distributed Lag-ARDL) Modeli kullanılmıştır. Analizden elde edilen bulgular, bankacılık sektörüne ait piyasa ve kredi riskinin hem uzun hem de kısa dönemde, sektörün operasyonel riskinin ise uzun dönemde, sektörün türev araç kullanımına istatistiksel olarak anlamlı etkide bulunduğunu göstermiştir. Analiz sonuçları, uzun dönemde, tüm açıklayıcı değişkenlerin türev araçlarla doğru yönlü bir ilişkisi olduğuna işaret etmesinin yanı sıra Türkiye'de bankaların özellikle operasyonel ve piyasa risklerinin yönetiminde türev finansal araçlara daha yoğun bir şekilde başvurduğunu ortaya koymuştur
SOSYAL SERMAYE VE BİLGİ PAYLAŞMA NİYETİ İLİŞKİSİNDE BİREYSEL MOTİVASYONUN ARACI ROLÜ
No full textİşgörenlerin belirli bir bilgiye sahip olması işletmeler açısından tek başına yeterli değildir. İşgörenlerin içinde bulunduğu ortam, işyerindeki bağlar, ortak dil kullanımı, işgörenlerin motivasyonları işgörenlerin bilgi paylaşma niyetini etkileyen önemli unsurlar olarak karşımıza çıkmaktadır. İşletme literatüründeki sosyal sermaye çalışmalarına bakıldığında daha çok bilgi paylaşımı ile olan ilişkiye odaklanıldığı görülmektedir. Çok az araştırma sosyal sermayenin motivasyonu nasıl etkilediğini ve sosyal sermaye ile paylaşma niyeti arasındaki ilişkide bireysel motivasyonun rol oynayıp oynamadığını incelemiştir. Bu çalışmanın amacı, sosyal sermayenin bilgi paylaşma niyeti üzerindeki etkisinde bireysel motivasyonun aracılık rolünün araştırılmasıdır. Araştırmadaki veriler, İstanbul’da hizmet sektöründeki işletmelerde çalışan toplam 262 beyaz yakalı çalışandan elde edilmiştir. Nicel araştırma yöntemi uygulanmış ve veriler yüz yüze ve e-posta anket teknikleri ile elde edilmiştir. Araştırmada korelasyon analizinden ve regresyon testlerinden yararlanılmıştır. Yapılan analizler sonucunda sosyal sermayenin bilgi paylaşma niyetini ve bireysel motivasyonu pozitif ve anlamlı olarak etkilediği sonucuna ulaşılmıştır. Aracılık rolüne dair analiz neticesinde bireysel motivasyonun sosyal sermaye ve bilgi paylaşma niyeti arasındaki ilişkide kısmi aracılık rolü olduğu tespit edilmiştir. Diğer bir deyişle çalışanların sosyal sermayeleri ve bilgi paylaşma niyetleri arasındaki ilişkiyi açıklamada bireysel motivasyon faktörlerinin de iyi anlaşılması gerekmektedir
A novel optimal power flow model for efficient operation of hybrid power networks
No full textIn the power industry, the design of an efficient optimal power flow (OPF) model is one of the important research challenges. This study presents the formulation and solution of the OPF problem in the presence of RESs, VSC-MTDC transmission lines, and FACTS devices, simultaneously. Fuel cost, voltage deviation, and power loss were selected as OPF objectives and optimized with state-of-the-art metaheuristic algorithms such as MFO, BSA, COA, MRFO, TLABC, and FDB-TLABC. Based on the optimization results, FDB-TLABC has obtained the best fuel cost results of 785.5850 /h, and 820.3022 $/h on the IEEE 30-bus power network. Besides, the algorithm reduced voltage deviation and active power loss by 11.76% and 0.52% compared to TLABC which second most successful algorithm, respectively. The experimental results are statistically analyzed using Wilcoxon signed-rank test. The analysis results show that the FDB-TLABC is a robust and powerful method to solve the introduced OPF problem
Intelligent Metasurface Layer for Direct Antenna Amplitude Modulation Scheme
No full textThis paper proposes a transmitter system based on direct antenna amplitude-shift keying modulation for point-to-point microwave link. The proposed system is formed from a conventional microstrip antenna and a novel reconfigurable metasurface layer (RMSL). The proposed RMSL has two states: OFF (or Logic-0) and ON (or Logic-1) where each switching scenario provides a certain gain level. This is achieved through controlling the proposed RMSL switching configuration to control the amplitude of the transmitted signal. Results show that such a system can modulate electromagnetic signals directly by varying the antenna's gain from about 2 dBi for Logic-0 to 13.8 dBi for Logic-1. An analytical model-based ray-tracing technique is invoked to explain the operation of the proposed antenna system. To demonstrate the operation of the proposed system, both the antenna and the RMSL structures were fabricated, assembled and tested. Measurements show good agreement with the theoretical model and numerical simulations obtained using CST Microwave Studio software package. The overall system has dimensions of 25 x 25 x 7.3 cm(3)
Fractional-order inverse filters revisited: Equivalence with fractional-order controllers
No full textThe equivalence of fractional-order inverse filters with fractional-order controllers is demonstrated in this work. This is achieved by appropriately rewriting the filters transfer functions in order to clarify the correspondence between the gain and time-constant of the filters and the scaling factor and differentiation/integration constant of the controllers. Possible implementations of fractional-order inverse filters using second generation voltage conveyors are presented and an application example, related to the control of a motion system, is demonstrated for evaluating the behavior of the introduced structures
A single CCII-based high-precision voltage-mode full-wave rectifier suitable for low-level signals
No full textA new second-generation current conveyor-based full-wave rectifier (FWR) is proposed in this work. The proposed voltage-mode FWR comprises a single active building block, four diodes, and three grounded resistors without needing any passive element matching problems. It does not suffer from any bias voltages and/or currents; therefore, it does not need extra circuitry. It can simultaneously provide positive and negative rectifications; thus, it is flexible. The proposed FWR has high input impedance; accordingly, it can be easily cascadable. Several simulations via the SPICE program and some experiments by using the AD844s are achieved. 0.18-mu m TSMC CMOS technology parameters are used in the simulations.Pamukkale University [2023UBD_I P001]Pamukkale University, Grant/Award Number: 2023UBD_I P00
The effect of acceptance commitment therapy-based group psychoeducation on neurocognitive functions in individuals with somatization symptoms
No full textLisansüstü Eğitim Enstitüsü, Psikoloji Ana Bilim DalıSomatizasyon, ruhsal sıkıntıların ve stresin bedensel belirtilerle ifade edilmesidir. Depresyon, kaygı bozukları gibi birçok başka psikolojik belirti ile ilişkisi bulunan, yaşam kalitesini olumsuz etkileyen somatizasyon nörokognitif işlevler üzerinde de olumsuz etkilere yol açmaktadır. Kabul ve kararlılık terapisinin somatizasyon üzerinde bir etkisi olduğu yapılmış birçok bilimsel araştırma ile gösterilmiştir. Ancak kabul ve kararlılık terapisini içeren bir müdahalenin somatizasyon belirtileri gösteren kişilerin nörokognitif süreçlerinde nasıl bir etkisi olacağını araştıran çalışma bildiğimiz kadarıyla henüz bulunmamaktadır. Araştırmada Psikolojik Belirti Tarama Ölçeği (SCL90)'ne göre somatizasyon belirtileri gösteren katılımcılar deney ve kontrol gruplarına rastlantısal olarak atanmış ve deney grubuna 8 haftalık kabul kararlılık terapisi temelli grup psikoeğitimi uygulanmıştır. Uygulama öncesi ve sonrası değerlendirmeler için SCL90, Perth Aleksitimi Ölçeği, Ağrı Felaketleştirme Ölçeği, Kabul ve Eylem Formu ve nöropsikolojik değerlendirmeler için de Wisconsin Kart Eşleme Testi, Stroop Testi, İz Sürme Testi ve Öktem Sözel Bellek Süreçleri Testi uygulanmıştır. Analizlerde SPSS 20 sürümü kullanılmıştır. Araştırma sonucunda, SCL90'ın somatizasyon, depresyon, obsesif belirtiler, kişiler arası duyarlılık, psikotizm, paranoid düşünce, fobik anksiyete ve toplam puanlarında, Perth Aleksitimi Ölçeği'nin tüm alt ölçek puanlarında, Ağrı Felaketleştirme puanlarında ve Kabul ve Eylem puanlarında deney grubu lehine anlamlı farklılıklar bulunmuştur. Nöropsikolojik testler için yapılan analizlerde ise Wisconsin Kart Eşleme Testi'nin toplam doğru sayısı ve perseverasyon alt ölçeklerinde anlamlı farklılık bulunurken, Stroop, İz Sürme ve Öktem Sözel Bellek Süreçleri testlerinde anlamlı farklılıklar bulunmamıştır.Somatization is the expression of mental distress and stress through physical symptoms. Somatization, which is associated with many other psychological symptoms such as depression and anxiety disorders and negatively affects quality of life, also has negative effects on neurocognitive functions. Many scientific studies have shown that acceptance and commitment therapy has an effect on somatization. However, as far as we know, there is no study investigating how an intervention involving acceptance and commitment therapy will have an effect on the neurocognitive processes of people with somatization symptoms. In this study, participants with somatization symptoms according to the Psychological Symptom Screening Scale (SCL90) were randomly assigned to the experimental and control groups, and an 8-week acceptance and commitment therapy-based group psychoeducation was applied to the experimental group. SCL90, Perth Alexithymia Scale, Pain Catastrophizing Scale, Acceptance and Action Form were used for pre- and post-application assessments and Wisconsin Card Sorting Test, Stroop Test, Trail Making Test and Öktem Verbal Memory Processes Test were used for neuropsychological assessments. SPSS version 20 was used in the analyses. The research findings indicate significant differences favoring the experimental group in SCL90 scores related to somatization, depression, obsessive symptoms, interpersonal sensitivity, psychoticism, paranoid ideation, phobic anxiety, and total scores, as well as in all sub-scale scores of the Perth Alexithymia Scale, Pain Catastrophizing scores, and Acceptance and Action scores. In the analysis of neuropsychological tests, significant differences were found in the total correct responses and perseveration sub-scores of the Wisconsin Card Sorting Test, whereas no significant differences were observed in the Stroop, Trail Making, and Öktem Verbal Memory Processes tests
Re-thinking group work in basic design education: A quantitative analysis of adapting exquisite corpse and decision tree approaches
No full textIn design education, especially in the first-year design studio, different approaches ranging from artistic to analytical and abstract to concrete have been used. This paper attempts to study one of those approaches namely Exquisite Corpse (EC), which is an art-stemmed approach, employed in the architecture's first-year design studio. In addition, decision-tree (DT) approach was used, which like EC, requires dialogue among students and helps foster problem-solving abilities by giving more structure to the educational medium as well. This paper uses quantitative methods to analyse the design process in the search for distinct methodologies in design research. The main purpose of this article is hence to evaluate the use of EC and DT in basic design education and to provide empirical implications for the development of the basic design teaching methodology. Descriptive statistics and a Pearson's chi-square test of independence were performed to examine the relationship between students' use of the exquisite corpse approach and their grades. The paper highlights the need for distinct methods for the scientific analysis of design research. The analysis used in this paper provides scholarly information to other design educators in higher education. The initial aim is to incorporate EC and DT in the final project were to help novice designers in guiding their design processes better. The research model of this study can help exemplify analytic research for design-related disciplines for future research studies