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© 2022 Hydrogen Energy Publications LLCMetal hydride (MH) storage is known as a safe storage method because it does not require complex processes like high pressure or very low temperature. However, it is necessary to use a heat exchanger due to the endothermic and exothermic reactions occurring during the charging and discharging processes of the MH tanks. The performance of the MH is adversely affected by the lack of a heat exchanger or a suitable temperature range and it causes non-stable hydrogen supply to the fuel cell systems. In this study, effect of the tank surface temperature on hydrogen flow and hydrogen consumption performance were investigated for the MH hydrogen storage system of a hydrogen Fuel Cell Electric Vehicle (FCEV). Different temperature values were arranged using an external heat circulator device and a heat exchanger inside the MH tank. The fuel cell (FC) was operated at three different power levels (200 W, 400 W, and 600 W) and its performance was determined depending on the temperature and discharge flow rate of the MH tank. When the heat exchanger temperature (HET) was set to 40 °C, the discharge performance of the MH tank increased compared to lower temperatures. For example, when the FC power was set to 200 W and the HET of the system was at 40 °C, 1600 L hydrogen was supplied to the FC and 2000 Wh electrical energy was obtained. The results show that the amount of hydrogen supplied from the MH tank decreases significantly by increasing the flow rate in the system and rapid temperature changes occur in the MH tank.

© 2022 Elsevier LtdTürkiye is the fastest-growing energy market among the OECD members, and it is among the world's top 20 energy-consuming countries. The existing electricity generation capacity of Türkiye has doubled in the last decade. Planning the electricity generation portfolio is an important problem for the decision and policymakers, especially in terms of sustainable development, and it is crucial for Türkiye's economic growth. In this paper, we study the long-term electricity generation portfolio optimization while considering the uncertainties. An optimization algorithm is modeled and solved while integrating uncertainty information as part of the Pareto concept. The results of three scenarios are presented and policy implications are discussed and compared with similar Turkish case studies and government projections. The results suggest that it is less risky to minimize emissions, thus, more likely to be sustainable than to minimize costs. Comparisons among solutions show that nuclear is a substitute for renewable resources and comparisons among other studies show that natural gas and hydro are substitutes for each other. Multi-objective formulation reveals that the government's scenario provides favorable results in business-as-usual conditions; however, nuclear and renewable investments that the government has planned are too ambitious to keep costs lower while decreasing emissions.

New technologies have been developed and adopted to generate energy from renewable sources to satisfy the increasing demand without causing environmental damage. However, estimating the power output of inherently intermittent, weather-driven, and non-dispatchable renewable energy sources is a major scientific and societal concern. In this study, a neural network model to enable short-to-middle term forecasts of a photovoltaic (PV) power system is provided. Using historical weather and power generation data, a non-linear autoregressive network with exogenous input (NARX) model is built to forecast the non-linear photovoltaic system output. The performance of the model is then analyzed by different statistical evaluation parameters. It is shown that the PV system power output estimation method can be successfully employed.

© 2021 Elsevier LtdElectricity consumption and generation are vital elements of a country's economic sustainability and growth. The United Nations proposes 17 sustainable development goals to achieve a better and more sustainable future. Four of these goals are related to affordable and clean energy, decent work and economic growth, sustainable energy infrastructure, and climate action. Aligned with these goals, we examine long-term power system capacity and generation expansion strategies where minimization of costs and greenhouse gas emissions and maximization of economic growth and employment strategies are considered. The optimization model is formulated as a large-scale, multi-period, mixed-integer linear program (MILP). We apply our model to Turkey which seeks to grow its economy using the energy sector in the face of a looming economic crisis while achieving emissions reduction targets. Additionally, we share key insights and policy implications resulting from the proposed plans. The results show that there is a conflict between traditional strategies and other sustainability measures such as pollutant emissions, economic growth, and employment rates. The cost minimization scenario yields significant investments in renewable energy sources with nearly equivalent investments in fossil fuel energy sources. Upon minimizing emissions, over half of the fossil fuel investments from the cost minimization case are displaced by investments in nuclear capacity. Similar investments in nuclear capacity are realized in the employment maximization and GDP maximization case, however, these cases yield relatively elevated fossil fuel investments and significantly reduced renewable investments.

Sosyal etkileşimi tanımlamada kullanılan konuşma çözümlemesi yöntemine olan ilgi son dönemde Türkiye’de artmaya başlamış ve bu yöntem, diğer sosyal bilimler alanlarında olduğu gibi eğitim araştırmalarında da sıklıkla kullanılmaya başlanmıştır. Ancak Türkçe alan yazında konuşma çözümlemesi yöntemini ayrıntılı olarak ele alan ve tartışan çalışmaların sayısının oldukça az olduğu görülmüştür. Bu çalışmanın amacı; konuşma çözümlemesinin ilkelerini tanıtmak, geçerli ve güvenilir bulgular elde edebilmek için veri toplama ve etkileşim çözümleme süreçlerine yönelik ayrıntılı bilgiler sunmak ve bu süreçlerde dikkat edilmesi gereken etik hususları tartışmaktır. Bu çalışmada konuşma çözümlemesinde geçerlik, güvenirlik ve etik konularına odaklanılarak Türkiye’de görece yeni oluşan alan yazına katkıda bulunulması ve bu yöntemle ilgilenen araştırmacıların bilgilendirilmesi de hedeflenmiştir.

© 2022.Lymphomas are the rare causes in the differential diagnosis of pituitary masses. While pituitary infiltration by lymphomas is relatively more frequent, isolated lymphoma associated with the pituitary gland is much rarer. We presented a case of a 64-year-old female patient who was admitted to the hospital due to headache, diplopia and decreased visual acuity. Although the stated preoperative diagnosis was pa-rasellar meningioma, the pathological diagnosis was given as isolated primary pituitary lymphoma after ruling out any other foci. After the definitive diagnosis, the patient under-went chemoradiotherapy. However, despite treatment, the patient died due to pulmonary sepsis. Primary pituitary lymphoma is an extremely rare condition generally seen in elderly and/or immunosuppressive patients. In order to es-tablish an effective therapeutic strategy, it is extremely cru-cial to distinguish between primary and secondary lymphomas. However, the recent evidence for a standardi-zed treatment protocol is still limited due to the small num-ber of cases reported to date.

In many countries, the electricity industry went through a deregulation process that changed it from a regulated and monopolistic/oligopolistic system to a liberal one. The new system allows independent producers to join the electricity market and sell electricity through bidding. In some markets, consumers can also bid to demand electricity. The characteristics of the liberalized electricity market in addition to its never-ending evolution make it difficult for students and young professionals to comprehend its structure and functioning. This manuscript sets out to achieve two goals. First, we will present a new web-based electricity trading simulation program that simulates the dynamics of the electricity market including investment and trading. Secondly, we compare classical classroom teaching methods against the simulation game teaching method to demonstrate the superiority of the latter in explaining the workings of the complex liberalized electricity market. Questionnaire results show that student’s knowledge increased by approximately 94%. Test results exhibit an average success rate of 80% for the game-related questions. The average success rate for subjects taught by classical methods is approximately 70%. The results show that the simulation game proves to be a better teaching method for complex subjects such as the liberalized electricity market.

In this research, it is aimed to determine the status of the preschool manipulative story books containing the activities which are placed before the stories, inside of the stories or after the stories, in terms of date of publications, subject of the stories and kind of the activities in the story. For this purpose, 188 books were investigated for sale in the bookstores of Ankara and Istanbul published between the years of 2005- 2015. Data were analyzed by using a statistical analysis program and findings were presented with frequency tables. The findings of the present study indicated that in the recent years the publication of the manipulative story books has increased. The present study also showed that the place of the activities in the books, the materials of the activities, and durability of the books are appropriate. But it has been determined that the age group of the book, the development area of the activities in the book and directives such as application period of the activites are incomplete in the books.

Yüksek Lisans Tezi, Bugün yaşam koşulları gözden geçirildiğinde, öğretim yöntemlerinin modern gereksinimler doğrultusunda, bireyleri eğitmek için yetersiz olduğu gerçektir. Çağcıl bireylerin yaşaml arı boyunca başarılı olmaları için kısa sürede ulaşılan bilgiyi uygulamaya dönüştürme yeteneğine sahip olmaları gerekmektedir Yapılandırmacılık, felsefe, psikoloji ve sibernetik alanlarında köklü bir bilgi teorisidir. Bilişsel gelişim ve öğrenme çalışmalarının yanı sıra genel olarak öğretme, psikoterapi ve kişilerarası yönetim uygulamaları için uygulaması geniş kapsamlı sonuçlara sahip olan iki ana prensibi ortaya koyar. Bunlardan ilki bilgi pasif bir şekilde alınmaz, fakat bilişsel konu tarafından aktif olarak oluşturulur; ikincisi ise bilişin işlevi uyarlayıcıdır ve ontolojik gerçekliğin keşfedilmesine değil, deneysel dünyanın örgütlenmesine hizmet eder. Sadece ilk prensibi kabul etmek, her ikisini de kabul edenler tarafından önemsiz yapılandırmacılık olarak kabul edilir. Çünkü bu prensip Sokrates'ten beri bilinen ve ikincisinin yardımı olmadan Batı epistemolojisinin tüm çok yıllık sorunlarına rastlamaktadır. Bu araştırma göreve yeni başlayan öğretmenlerin yapılandırmacı öğretime yönelik tutumlarını incelemeyi amaçlamıştır. Çalışma grubunu 2018-2019 öğretim yılı Ümraniye'de bulunan 20 resmi ilkokul ve ortaokuldan seçilen 250 öğretmen oluşturmaktadır. Araştırma sonuçları alanyazında incelenen diğer çalışmalarla benzerlik göstermektedir., Today, when living conditions are reviewed, it is the fact that teaching methods are insufficient to educate individuals in accordance with modern requirements. In order to be successful throughout their lives, contemporary individuals need to have the ability to convert the information reached in a short time into practice. Constructivism, philosophy, psychology and cybernetics. In addition to cognitive development and learning studies, the practice of teaching, psychotherapy and interpersonal management practices in general provides two main principles with broad conclusions. First, the information is not taken passively, but it is actively created by the cognitive subject; second, the function of cognition is adaptive and serves not to discover ontological reality, but to the organization of the experimental world. Only accepting the first principle is regarded as insignificant by those who accept both. Because this principle has been known since Socrates, and without the help of the latter, it has coincided with all the perennial problems of Western epistemology. This study aimed to investigate the attitudes of new teachers to constructivist teaching. The study group consisted of 250 teachers selected from 20 primary and secondary schools in Ümraniye, 2018-2019 academic year. The results of the research are similar to the other studies examined in the literature.