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Life Cycle Assessment of Green Methanol Production Based on Multi-Seasonal Modeling of Hybrid Renewable Energy and Storage Systems
No full textThis study evaluates the environmental implications of green methanol production under seasonal energy variability through a dual-comparative analytical framework. The research employs ReCiPe 2016 Endpoint (H) methodology to assess four seasonal renewable energy configurations (with varying solar–wind ratios across seasons) against conventional grid-based production, utilizing a hybrid battery storage system combining lithium-ion and vanadium redox flow technologies. The findings reveal significant environmental benefits, with seasonal renewable configurations achieving 24.38% to 28.26% reductions in global warming potential compared to conventional methods. Monte Carlo simulation (n = 20,000) confirms these improvements across all impact categories. Our process analysis identifies hydrogen production as the primary environmental impact contributor (74–94%), followed by carbon capture (5–13%) and methanol synthesis (0.5–4.5%). Water consumption impacts show seasonal variation, ranging from 16.55% in summer to 11.62% in winter. There is a strong positive correlation between hydrogen production efficiency and solar energy availability, suggesting that higher solar energy input contributes to improved production outcomes. This research provides a framework for optimizing sustainable methanol production through seasonal renewable energy integration, offering practical insights for industrial implementation while maintaining production stability through effective energy storage solutions
Development of rainfall intensity-duration-frequency curves under nonstationary conditions
No full textIntensity-duration-frequency (IDF) curves, developed conventionally with the assumption of stationarity, for maximum rainfall time series have been used in the design of hydraulic structures for many years. However, recent studies have shown that climate change may violate the stationarity assumption on hydrometeorological time series, thus hindering the reliable use of probability distribution functions and their parameters in practice. Therefore, nonstationary models considering changes in extremes due to changes in climate have gained importance. This study focuses on the frequency analysis of 14 standard duration annual maximum rainfall time series recorded at 20 meteorological stations across the Black Sea Region in northern Türkiye. Intensity-duration-frequency (IDF) curves were developed under both stationary and nonstationary conditions. Generalized Extreme Value (GEV) models were constructed for all stations assuming stationarity, while nonstationary models were developed only for stations with a trend component. Time and climate oscillations, specifically the Arctic Oscillation (AO) and the North Atlantic Oscillation (NAO), were chosen as covariates in nonstationary models based on their significant correlation with annual maximum rainfall. Additionally, this study investigated the 1-, 2-, and 3-month delayed effects of remote teleconnection patterns, which serve as covariates to derive nonstationary IDF curves for stations with temporal trends. The Deviance Information Criterion (DIC) was employed to determine the best-fit GEV model, and parameters were estimated using the Bayesian Markov Chain Monte Carlo (MCMC) simulation technique. The results indicated that stationary models were the best-fit for 10 stations, while nonstationary models were optimal for 10 stations, with the latter often incorporating time or climatic oscillations such as the NAO or AO. Notably, a significant finding was the increase in return levels with the nonstationary model incorporating a time covariate at the Rize station, ranging from 26.4 to 21.5% for durations of 5 min and 24 h, respectively. Furthermore, some stations showed a significant correlation between the maximum precipitation and the AO/NAO indices, either in the current month or with delays. The study emphasizes the importance of considering nonstationarity when developing IDF curves for annual maxima of daily and subdaily rainfall series
The construction of neoliberal subjectivities in graduate education in the context of human capital discourse
No full textAhşap Yapılarda Parametrik Tasarımın Değerlendirilmesi
No full textYapı malzemeleri ve teknolojisindeki gelişmeler, binaların tasarım süreçlerinde önemli bir rol oynamaktadır. Giderek karmaşıklaşan mimari formlar, yapı mühendisliğinin sınırlarını zorlamaktadır. Dijital algoritmalar ve matematiksel modeller kullanılarak belirli parametrelerin değiştirilmesiyle farklı tasarım alternatiflerinin oluşturulmasına olanak tanıyan parametrik tasarım yöntemleri ve bu yöntemlerle uyumlu yapı malzemesi kullanımı her geçen gün daha fazla önem kazanmaktadır. Ahşap, sürdürülebilir ve yenilenebilir bir yapı malzemesi olarak estetik ve teknik özellikleriyle modern mimaride önemsenmektedir. Aynı zamanda, çevresel sürdürülebilirlik ve enerji verimliliği açısından da yapı sektöründe stratejik bir önemi bulunmaktadır. Parametrik tasarımın dijital araçlarla uyumu ise ahşap yapıların tasarım, üretim ve uygulama süreçlerinde büyük avantajlar sağlamaktadır.Bu çalışmada, parametrik tasarımın ahşap yapılarda daha karmaşık, estetik ve yaratıcı formlar oluşturma potansiyelinin belirlenmesi amaçlanmaktadır. Çalışmada, literatür taraması ve örnek ahşap yapı analizleri yoluyla parametrik tasarımın ahşap yapıların üretiminde kullanımı ve yapı endüstrisindeki uygulama potansiyelleri ele alınmakta; ayrıca ahşap yapıların dayanıklılığı, işçilik, süre ve maliyet üzerindeki etkileri tartışılmaktadır. Parametrik tasarımın mimarlıkta tanımı, tasarıma etkileri, tasarım süreçleri ve kullanılan dijital programlar araştırılmaktadır. Ahşabın parametrik tasarımda kullanımı, çok katlı ve geniş açıklıklı sistemlerdeki yeri, yapı bilgi modellemesiyle ilişkisi, üretilebilirlik, uygulanabilirlik ve sürdürülebilirlik açısındandeğerlendirilmektedir.Sonuç olarak bu çalışmada, parametrik tasarımın ahşap yapılarda nasıl daha verimli, estetik ve ekonomik şekilde kullanılabileceği araştırılmaktadır. Ahşap yapı üretim sürecindeki sorunlar ve fırsatlar detaylı bir şekilde değerlendirilerek, parametrik ahşap yapılar üzerinde yapılacak vaka incelemeleri ile ahşap yapıların parametrik tasarım ile nasıl daha yenilikçi, verimli ve sürdürülebilir hale getirilebileceği tartışılmaktadır.</p
The Effect of Pharmaceutical Care Practices on Clinical Problem-Solving Decision-Making Competencies and Students’ Preparedness: A Cross Sectional Study
No full textBackground: As clinical responsibilities continue to grow, it becomes essential for clinical pharmacists to acquire advanced competences, such as patient monitoring, patient-specific drug therapy design and evaluation, and collaboration with healthcare professionals. Pharmacy schools aspire to equip young pharmacists with competencies relevant to their current needs through the clinical practice courses they offer. Therefore, investigating the impact of clinical practice from the students’ perspectives is crucial. Aim: The study aims to explore the influence of experiential learning provided in Pharmaceutical Care (PC) courses on students' level of perceived professional readiness, clinical problem-solving, reasoning, and decision-making skills. Materials and Methods: This study is a cross-sectional survey. Data were collected from a total of 278 students of PC courses using two questionnaires: Perceptions of Preparedness to Provide Pharmaceutical Care (PREP) scale and the Clinical Pharmacist Competencies Self-Evaluation Questionnaire (CPCSE). Results: The reliability coefficients of the PREP and CPCSE questionnaires were calculated as 0.95 and 0.98, respectively. There was a statistically significant difference between the semesters in the students' readiness perceptions, and the students' perceptions were at the highest level at the end of the PC practices (p<0.00). A statistically significant linear relationship was found between the students' perception of readiness at the end of the 9th semester and their problem-solving and decision-making competencies (r = 0.534 p<0.000). Conclusion: The results of the study highlight possible areas for curricular improvement. Given that the students deemed themselves to be least prepared for the administrative procedures, the curriculum should be reconsidered in this respect. The findings derived from the competency survey further underscore the necessity for curriculum modifications about drug administration and collaboration
The place-new relation in the context of experience and meaning: a bibliometric review (1992-2023)
No full textThe research analyzes the literature by questioning the common denominator between “place and the new” through the concepts of experience and meaning to expand and deepen the existing knowledge on the meaning of place in the production of place. The paper discovers current approaches and notions in the place-new relationship and identifies leading keywords, authors, documents, sources, organizations, and references. It presents a systematic literature review based on bibliometric data in the context of place concept research. The analysis conducted on 27 May 202327 May 2023, with the concepts of place, new, experience, and meaning, covers the bibliometric data of 870 publications which included English articles and book chapters published since 1992 and chosen from specific research categories on the Web of Science. Documents published before 1992 without available content were excluded. Findings show an increasing tendency towards the concepts of sustainability, place-making, place attachment, urban regeneration, architectural design, and cultural heritage. While the number of investigations concentrating on landscape and COVID-19 has increased; concepts like everyday life, emotions, behavior, urban politics, phenomenology, design research, and displacement have been discovered as current research topics. This paper is potentially useful for future theoretical and practical work to create meaningful places and contributes to the further implementation of design and planning studies
Young Adults' Accessible and Affordable Housing Challenge in Istanbul
No full textThe purpose of this study is to explore the current housing challenges faced by young adults (18-35), particularly those in their early careers, often have limited incomes, which restricts their access to housing. For this purpose, the housing challenge around the world, in Turkey and Istanbul, has been presented. Within the study, the problem of housing accessibility is discussed in the context of changing demographic structure, affordability, and accessibility to qualified housing. The study is a literature review conducted to fill a significant gap in the existing literature. The existing literature has been analysed by content analysis method and the findings have contributed to a deeper understanding of the subject. This study highlights the incompatibility of the existing housing supply with changing household structures, income distributions, and lifestyles and demonstrates the growing demand for smaller housing units. In this context, the study addressed a few questions: “RQ1: In what ways do demographic changes and economic factors influence the accessibility of housing for young adults in large cities?” and “RQ2: How the increasing demand for small, affordable and functional housing is being addressed in the current housing market and what policy recommendations can be made to improve this situation?” Demographic changes such as the decrease in household size, the increase in the number of individuals living alone, and the aging population, as well as the increase in the number of divorces and the desire of young adults in the early stages of their careers to live in the city center, highlight the need for small, affordable, and functional housing. However, the existing housing stock is far from meeting these changing needs. The challenges young adults face in the housing market, affect not only their individual well-being but also the economic and social dynamics of cities. Therefore, it is critical that housing policies take into account the economic and social needs of young adults and create more accessible and affordable solutions. The study found that smaller dwelling size can offer an important solution that supports not only the physical need for shelter but also the social and economic cohesion of young adults in metropolitan areas. The original contribution of this study to the literature is that it reveals the negative effects of the lack of planning of housing provision in accordance with current demographic and economic conditions on housing accessibility and, in this context, offers solutions for the development of user-oriented, inclusive, and sustainable housing policies.Keywords: Housing Challenge, Accessible Housing, Changing Demographic Structure, Affordable Housing, Qualified Housing</p
Existence and Physical Properties of Gradient Ricci-Yamabe Solitons
No full textWe first prove the existence of the gradient Ricci-Yamabe soliton (briefly GRYS) by constructing an explicit example endowed with the Robertson-Walker metric. Then we focus on the physical properties of the gradient Ricci-Yamabe solitons satisying Einstein's field equations, under the assumptions of different subspaces of Gray's decompositions. For instance, we prove that if a GRYS space-time satisfying Einstein's field equations, in which the gradient of the potential function psi is a unit-timelike torse-forming vector field, belongs to the subspaces B and B', then it is a Robertson-Walker space-time with vanishing shear and vorticity. Moreover, its possible local cosmological structures are of Petrov types I, D, or O. Finally, we obtain the equations of state of a perfect-fluid space-time admitting the GRYS whose velocity field is a unit-timelike Killing vector field
A novel approach using experimental results of mixed refrigerants and entropy-weighted TOPSIS optimization for the sustainability of hydrogen pre-cooling liquefaction process
No full textThe global massive rise in consumption of power and energy has led to an increased elevation of the status of hydrogen energy as a primary clean fuel for the future. However, the liquefaction stage of hydrogen presents a real challenge because of the high power that accompanies the standard practices. This study investigates application of mixed refrigerants in the hydrogen liquefaction process. by creating and experimenting multiple combinations of mixed refrigerants. This work utilizes a novel approach in ranking mixed refrigerants on the criteria components. Notably, mixed refrigerant trial 5 emerges as the optimal choice, achieving a substantially improved Specific Energy Consumption (SEC) of 1.16 kWh/kgLH2 and Coefficient of Performance (COP) of 3.52. The optimized values result in a remarkable 72% reduction in SEC and a 57% enhancement in COP as compared to Joule-Brayton cycles, showcasing the potential for significant energy savings