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Bu çalışma, 1990-2016 döneminde koordineli piyasa ekonomileri için tarımsal katma değerin, orman alanlarının, ekonomik büyümenin ve yenilenebilir ve yenilenemez enerji tüketiminin çevresel kalite üzerindeki etkisini panel Common Corelated Effects (CCE) modelini kullanarak incelemeyi amaçlamaktadır. Panel CCE modelinden elde edilen uzun dönem katsayılara göre orman alanlarının çevre kalitesini arttırdığı, başka bir ifadeyle karbondioksit emisyonunu azalttığı, yenilenemez enerji tüketiminin ve ekonomik büyümenin ise çevre kalitesi üzerinde negatif bir etki oluşturduğu tespit edilmiştir. Ayrıca, incelenen dönemde tarımsal katma değerin ve yenilenebilir enerji tüketiminin çevre kalitesi üzerinde bir etki oluşturmadığı görülmüştür. Son olarak değişkenler arasındaki nedensellik ilişkisi Dumitrescu–Hurlin testi ile araştırılmıştır. Uygulanan nedensellik testi ile tarım ile karbondioksit emisyonları, tarım ile yenilenemez enerji tüketimi, yenilenebilir enerji tüketimi ile yenilenemez enerji tüketimi arasında çift yönlü nedensellik ilişkisi elde edilmiştir.

AbstractThis study analyzes oil price exposure of the oil–gas sector stock returns for the fragile five countries based on a multi-factor asset pricing model using daily data from 29 May 1996 to 27 January 2020. The endogenous structural break test suggests the presence of serious parameter instabilities due to fluctuations in the oil and stock markets over the period under study. Moreover, the time-varying estimates indicate that the oil–gas sectors of these countries are riskier than the overall stock market. The results further suggest that, except for Indonesia, oil prices have a positive impact on the sectoral returns of all markets, whereas the impact of the exchange rates on the oil–gas sector returns varies across time and countries.

После завоевания Крыма и Черноморского побережья Россия начинает экспансию на Кавказ. Покорение кавказских народов было доверено генералу А. Ермолову, жестокому, деспотичному, часто сравниваемому с Кромвелем. С 1830 по 1859 гг. местные народы оказывали стойкое сопротивление царской армии, однако в конце концов Шейх Шамиль сложил оружие. Наступил один из самых мрачных периодов российского империализма, многие оказались в изгнании и эмиграции в Турции. Цель нашего исследования заключается в изучении поливариантности кавказского текста русской литературы на примере рассказа А. Бестужева-Марлинского “Аммалат-бек”. Задачи статьи предполагают раскрытие мотивной структуры произведения, демонстрацию его антиколониальной направленности. В статье рассмотрен чрезвычайно знаковый рассказ А. Бестужева-Марлинского “Аммалат-бек” с точки зрения национальных стереотипов, имагологии, образов колонизации на Кавказе, местной экзотики и колорита. Анализ этнических стереотипов и имиджей способствует более глубокому пониманию сюжета, композиционной структуры повествования, символического пласта текста. Немаловажное значение принадлежит батальным сценам, их роли в формировании традиции дальнейшей русской литературы. Жанровая специфика произведения также проливает свет на особенности художественного синтеза в рассказе Бестужева-Марлинского. Романтизация повествования свидетельствует о том повышенном авторском внимании, которое автор придавал изображению азиатских народов. Подчеркнута связь кавказских мотивов в данном рассказе с историческим процессом, личной судьбой, биографическими перипетиями самого писателя. Интерпретация учитывает теоретические достижения постколониальной критики, возможность амбивалентной оценки географических и ментальных границ, стереотипов, образов и концептов национальной картины мира. Особое внимание уделено этническим стереотипам, антропологическим кодам, национальной специфике предмета отображения. Выявлены различия между западным и восточным мировосприятием, имперским и колониальным, историей государства и локальной историей. Акцентированы индивидуальные особенности психологии героя, его поведения, связи с этническим коллективом, нацией. Прослежена художественная динамика характера, трансформация его внутреннего мира, диалектика связей с другими персонажами.

Beyond the anticipated experience associated with tourism destinations, the United Nations World Tourism Organization (UNWTO) has further tasked (especially the destination countries) on the importance of tourism to achieving the 2030 Sustainable Development Goals (SDGs). From this dimension, this study employed the ecological footprint of the 10 most visited countries (France, Spain, United States, China, Italy, Mexico, United Kingdom, Turkey, Germany, and Thailand) over the period 1995-2016. Specifically, the study employed an econometric approach and found that increase in tourism arrivals and globalization is detrimental to the attainment of sustainable environmental quality in a long term. Precisely, a 1% increase in international arrivals and globalization is responsible for a 0.18 and 0.89% increase in ecological footprint in the long-run. These impacts of tourism activities and globalization are detrimental to the environmental quality of the destination countries. Meanwhile, the real income per capita and biocapacity in the destination countries improve the environmental quality of the panel of destination countries in the long-run. In addition, the study found significant evidence of Granger causality from tourism and real income to ecological footprint without feedback, the globalization-ecological footprint Granger causality nexus is with feedback. Moreover, potentially effective policies for government and other stakeholders especially toward attaining Global goals were proffered in the study.

Çalışmada, mevcut durumda elektrik anahtarlarında kullanılan bakır ve pirinç hammaddelere göre daha uygun maliyetli bir alternatif olacağı düşünülen Al-Cu bimetalik hammaddesinin elektrik anahtarlarında kullanımının IEC standartları açısından uygunluğu araştırılmıştır. IEC 60669-1 elektrik anahtarları standardının en belirleyici testi olan aşırı akım testinde, iletkenlerin artan ısınma miktarları incelenmektedir. Anahtarın iletkenlerinden ürünün beyan akımının (In:10A) 1,35 katı aşırı akım geçirilerek iletkenlerdeki maksimum sıcaklık artış miktarının (ΔT) 45°C altında olması istenmektedir. Araştırmada, üç farklı hammadde (Al-Cu, pirinç ve bakır) ile oluşturulmuş ürün dataları, standartta belirtilen sınır şartları dahilinde multi-fizik simülasyonlara tabi tutulmuş ve laboratuvar testleri yapılmadan önce sıcaklık artışı ile alakalı teorik sonuçlara ulaşılmıştır. Simülasyona göre en yüksek sıcaklık artışı 20,5°C ile pirinç, en düşük sıcaklık artışı 17,25°C ile bakır numunede gözlemlenmiştir. Al-Cu numunede ise 19,9°C sıcaklık artışı gözlemlenmiştir. Simülasyonlardan sonra yapılan laboratuvar testlerinde simülasyon verilerine yakın sonuçlar alınmıştır. Test sonuçlarına göre en yüksek sıcaklık artışı meydana gelen pirinç numunede 22,63°C, en düşük sıcaklık artışı meydana gelen bakır numunede 19,14°C ve Al-Cu numunede ise 20,72°C sıcaklık artışı gözlemlenmiştir. Sırasıyla pirinç, Al-Cu ve bakır için analiz-deneysel veri sapma miktarları şu şekildedir; %10,37, %4,10 ve %10,95. Bu verilere göre hiçbir numune maksimum 45°C miktarını aşmamıştır ve numunelerin tamamı standart açısından uygundur. Direncin ısınma ile doğru, iletkenlik ile ters orantılı olduğu bilinmektedir. Bu bilgiler ve test sonuçlarından yola çıkılarak hammaddelerin iletkenlik miktarları için bakır>Al-Cu>pirinç sıralaması yapılabilir. Simülasyon ve deneysel doğrulama sonuç verileri incelendiğinde Al-Cu bimetal hammaddesinin, uluslararası elektrik anahtarları standardındaki aşırı akım testlerini geçerek elektrik anahtarlarında pirinç ve bakır iletkenlere alternatif olarak kullanılabileceği sonucuna ulaşılmıştır.

Buildings consume more than a third of the world's energy demand, and painstaking adjusting the insulation thickness of external walls is an effective way to save energy. Thermal insulation plays an important role by reducing the heat transfer rate to save energy, and it is important to determine the thickness of the appropriate insulation material in the walls. In this research, considering only the heating factor, four different building materials (Pumice, Hollow concrete block - HCB, Hollow red clay block - HRCB and Reinforced concrete - RC) and eight different insulation materials (Extruded polystyrene - XPS, Expanded polystyrene - EPS, Expanded polyurethane - PUR, Wood fiber - WF, Hemp fiber - HF, Linen fiber - LF, Fiber glass - FG and Sheep wool - SW) are investigated on the exterior of a building in Sivas province of Türkiye. To reach more accurate results, life cycle cost analysis is taken as a basis, and the optimal insulation thicknesses, payback periods and energy savings of 32 different wall + insulation combinations with solar radiation (SR) are estimated using heating degree-hours. The heating requirement of a building covers more than three quarters of the year in Sivas, depending on different facing walls. These rates are calculated as 85 % (without SR), 80 % (North), 78 % (West), 77 % (East) and 75 % (South). Results also showed that the total minimum heating cost, the total maximum energy saving cost and the shorthest payback period are obtained HRCB + FG + South with 14.19 €/m2, RC + FG + solar radiation free with 72.76 €/m2 and RC + LF + solar radiation free with 1.60 year.

Abstract Conventional room air conditioners consume a significant amount of energy, and thereby negatively affect the environment. In this perspective, passive air conditioning systems using phase change material (PCM) are very promising and widely investigated recently. In this study, influence of a PCM-based passive air conditioner on temperature distribution was experimentally studied in a test room under the local tropical climatic conditions. Coconut oil and water were used for latent heat storage and sensible heat storage, respectively. A storage panel was constructed with two openings—an outlet for conditioned air and an inlet for indoor air, then filled with coconut oil or water to create an additional internal thermal mass (ITM) in the room. The storage material was discharged at night in the indoor or outdoor, and stratum air circulation was utilized to provide the conditioned air into the room during diurnal period. Temperature measurements were conducted at five vertical and five horizontal points. The gained results showed that employing ITM heat storage panel in the room reduced peak temperatures and enhanced the thermal environment. Coconut oil ITM provided 0.5 °C lower peak temperature in the occupant zone while greater temperature reductions were observed in the upper zone compared to the reference case. In addition, ITM panel significantly decreased the observed temperature fluctuations throughout a day. This study revealed that ITM-based stratum air circulation can be a profound solution to the existing high energy consumption problem of conventional air conditioners used in the small urban houses under tropical climate.

This study focuses on applying machine learning (ML) techniques to fluid mechanics problems. Various ML techniques were used to create a series of case studies, where their accuracy and computational costs were compared, and behavior patterns in different problem types were analyzed. The goal is to evaluate the effectiveness and efficiency of ML techniques in fluid mechanics and to contribute to the field by comparing them with traditional methods. Case studies were also conducted using Computational Fluid Dynamics (CFD), and the results were compared with those from ML techniques in terms of accuracy and computational cost. For Case 1, after optimizing relevant parameters, the Artificial Neural Network (ANN), Random Forest (RF), and Support Vector Machine (SVM) models all achieved an R² value above 0.9. However, in Case 2, only the ANN method surpassed this threshold, likely due to the limited data available. In Case 3, all models except for Linear Regression (LR) demonstrated predictive abilities above the 0.9 threshold after parameter optimization. The LR method was found to have low applicability to fluid mechanics problems, while SVM and ANN methods proved to be particularly effective tools after grid search optimization.