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Energy based on renewable energy sources continues to meet the increasing need of growing population. In renewable energy production, not only energy production but also efficient using is crucial. In recent years, photovoltaic panels, which are increasingly used and highly important, have warmed on the surface due to the radiation energy emitted by the sun, and this warmth reduces the efficiency of the panel. In this study, it is aimed to reduce this efficiency loss by using phase changing material with latent heat which is one of the thermal energy storage methods. One of the two solar panels placed parallel to the ground was filled with phase changing material. With this, it is aimed to cool photovoltaic panel by using calcium chloride hexahydrate phase changing material; and radiations air temperature, current, voltage, power, surface temperature, efficiency graphs were obtained. As a result of simultaneous measurements, the increase in yield was 2.95%.

We researched China's climate and sustainable development goal with relevant and susceptible instruments capable of inducing and mitigating carbon emissions. Amidst the contributor to the global carbon emissions, China is caught in between mitigating its carbon emission and aiming towards placing its national contribution of emissions to the acceptable levels of 1.5 °C and below 2 °C. Following the intricacies surrounding China's sustainable development as it contains its economic and environmental performance, we adopt China's data of 1980 and 2018 with different scientific approaches (nonlinear autoregressive distributed lag (NARDL), dynamic ordinary least square test, and bootstrap Granger causality) with different instruments (such as economic growth, financial development, renewable energy, and innovation policies) to research China's sustainable development. For clear exposition and insight into our findings with policies attached, we draw a conclusion from the outcomes of the mentioned approaches. From NARDL and dynamic ordinary least squares (DOLS), we find that economic growth through economic activities is statistically significant in determining the trend (increase) of carbon emissions in China in both periods (short run and long run). However, other selected instruments (financial, renewable, and innovation policies) tend towards controlling and moderating the carbon emissions in China. Thus, China has good prospects to mitigate its carbon emissions if considered tailoring its policies towards favorable instruments. From bootstrap Granger causality, we find similar inferential results that support previous findings thereby confirming the positive implication of the selected instruments to China's sustainable development. Hence, the nexus that is established among the selected instruments clearly show the importance of technological innovation and renewable energy in mitigating carbon emissions.

The construction industry is considered as one of the least productive, highest energy consuming, and least digitized industries. The Lean Management (LM) philosophy became a significant way for eliminating non-value-added activities and wastes during a building’s lifecycle. However, studies have shown that philosophies are not efficient by themselves to solve the issues of the construction industry. They need to be supported with the appropriate technologies and tools. Therefore, the integrated use of Building Information Modelling (BIM) with LM or Value Engineering (VE) were proposed in the literature. Nonetheless, it was also seen that BIM can provide more insights and improvements when BIM is integrated with data analysis tools to analyze BIM data. In the literature, the synergies between these concepts are generally addressed pairwise, and there is no comprehensive framework which identifies their relationships. Therefore, this study aims to develop a maturity framework that facilitates the adoption of LM, VE, BIM, and Big Data Analytic (BDA) concepts to address long-standing productivity and digitalization issues in the Architecture, Engineering, and Construction (AEC) industry. Design Science Research (DSR) methodology and its three-cycle view (relevance, rigor, and design cycle) were applied to build the proposed maturity framework. Two interviews were performed to identify and observe research problem in relevance cycle. In the rigor cycle, a comprehensive literature review was performed to create a base for the development of the maturity framework. In addition to the developed base of the framework, lean processes were added to this cycle. In the design cycle, the developed framework was evaluated and validated by five experts through face-to-face interviews. The importance of employer’s requirements to adopt the proposed methodologies, the negative impact of change orders, the importance of pre-construction phases to facilitate value creation and waste elimination, and the usage of common data environment with BIM were identified as the prominent application and adaptation issues.

Fars dilinde t- ile başlayan birkaç sözcük, anlam değişikliğine uğramadan Türkçede k- ile başlar. Yine Farsçada k- ile başlayan birkaç sözcüğün herhangi bir anlam değişikliğine uğramadan Türkçede t- ile başladığı görülür. Bilindiği üzere t ile k ünsüzlerinin ses değerleri birbirinden farklıdır. Bu incelemede Türkçe-Farsça sözcüklerde görülen söz başı t-/k- sorunu ele alınmıştır. Söz başı t-/k- denkliği Türkçenin kendi içinde saptanmış bir denkliktir. Ancak iki farklı dil ailesinden olan Türkçe ile Farsçada görülen söz başı t-/k- denkliği daha önce ele alınmamıştır. Bu nedenle Türkçe ile Farsçada görülen söz konusu denkliği taşıyan sözcüklerin kökeni mercek altına alındı. İncelemede, Türkçe ile Farsçada t-/k- denkliği bulunan kırık “kırık” / terek “çatlak”, / kabar “kabarmış yara” / tāvel “kabarmış yara”, kırış- “kırışmak” / terenc- “kırışmak” gibi sözcüklerin hangi dile ait olduğu sorununa açıklık getirilmek istenmiştir. Bu doğrultuda söz konusu sözcüklerin kökeni dil aileleri düzeyinde ele alındı. Öncelikle t- ve k- denkliği bulunan sözcüklerin eski Türkçe ile eski İranî dillerdeki kullanımı araştırıldı. Daha sonra çalışmaya dâhil edilen Farsça sözcüklerin Hint-Avrupa kökenli olup olmadığı mercek altına alındı. Son aşamada Altay dillerinden Moğol, Tunguz, Japon ve Kore dillerinde, üzerinde durduğumuz Türkçe sözcüklerin kökteşlerinin kullanılıp kullanılmadığı araştırıldı. Böylece karşılaştırmalı yöntemin kullanıldığı bu incelemede sözcüklerin kökeniyle ilgili sonuç çıkarmamızda Altay dil ailesiyle Hint-Avrupa dil ailesi belirleyici oldu. 

In this paper, the effect of nanoparticles with different fractions on fiber, matrix and void volume fraction was investigated. Vacuum assisted resin transfer molding (VARTM) method was used to manufacture the carbon fiber/epoxy nanocomposite laminates. Before manufacturing, nanoparticles were added to epoxy with different fractions. Manufactured nanocomposites were applied to burning test after they cut into the size referred in standards. When fraction of nanoparticles increased, both the viscosity of epoxy and agglomeration of nanoparticles in epoxy increased. As a result, vacuuming of epoxy under pressure and wetting the fibers get hard while manufacturing. After burning test, it was found that adding 5% nanoparticles would increase void volume fraction by %221.

Bu çalışmada, Elazığ yakın çevresinde üç farklı bölgede bulunan volkanik kayaçların jeokimyasal ve Sr-Nd izotop verilerine dayalı olarak deneştirilmeleri yapılmıştır. Bölgedeki volkanizma, esas olarak bazaltik lav akıntıları ile daha az yayılımlı bazik cüruf konileri ve piroklastik kayaçlardan oluşmuştur. Kuvaterner yaşlı bu bazaltik lavların jeokimyasal verileri, kayaçların silise doymamış alkali ve yüksek K’lu özellikte; potasik trakibazalt, hawaiit ve bazanit bileşiminde olduğunu gösterir. Volkanitlerin ana ve iz elementlerinin SiO2 ile değişimleri ve element içerikleri, genelde birbirleriyle uyumlu olarak bulunur. Benzer dağılım kondrit ve ilksel mantoya göre normalize edilmiş çoklu element değişim diyagramlarında da görülmektedir. Örneklerde büyük iyon litofil elementlerin zenginleşmesine karşın yüksek alan kuvvetine sahip elementlerin tükenmesi, düşük 87Sr/86Sr(i) (0.7034988-0.7039231) ve yüksek 143Nd/144Nd(i) (0.512829-0.512884) izotop içerikleri ve pozitif ɛNd (3.76-4.84) değerleri ile jeokimyasal verilerin değerlendirilmesi sonucunda, bu volkanitlerin tüketilmiş mantodan türemiş, kalınlaşan kıtasal kabuğa bağlı kirlenmeyle beraber yitime bağlı olarak yitim ergiyiklerinin neden olduğu metasomatizmadan da etkilendiğini göstermektedir.

Abstract This article discusses the analysis and study of the energy efficiency of the operation of a voltage stabilizer using a non-contact voltage relay. In addition, the calculation of the energy efficiency from the use of the stabilizer is presented on the example of the enterprise of the Baysun district power supply of the Surkhandarya region. Summarizing the results of the analyzed and investigated energy efficiency of the prototype of the stabilizer, it can be stated that it fully meets the requirements for such devices and can ensure reliable operation of the power supply network of household electrical receivers with a voltage of 0.4 kV.