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MODERN ARCHITECTURE IN IRANIAN HOUSING DURING THE PAHLAVI ERA: A SUSTAINABILITY PERSPECTIVE
No full textBu çalışma, Avrupa’da eğitim görmüş mimarların etkisi ve hızlı modernleşmenin damgasını vurduğu İkinci Pehlevi döneminde İran konut mimarisinde sürdürülebilirlik ilkelerinin entegrasyonunu incelemektedir. Farklı iklim bölgelerinden on ev, yedi kriteri kapsayan matris tabanlı bir yöntem kullanılarak değerlendirilmiştir: doğal aydınlatma, havalandırma, yapı malzemeleri, iklim adaptasyonu, yeşil/açık alan, pasif enerji stratejileri ve mekansal form. Her kriter, arşiv fotoğrafları ve çizimlere dayalı olarak dört puanlık Likert tipi bir ölçekte değerlendirilmiştir. Her kriter, 0’ın entegrasyon olmadığını, 3’ün tam entegrasyon olduğunu gösteren dört puanlık Likert tipi bir ölçekte (0-3) değerlendirildi. Toplam puanlar 21 puanlık bir ölçekte hesaplandı ve evler üç gruba ayrıldı: düşük performans (0-9), orta performans (10-14) ve yüksek performans (15-21). Sonuçlar, modernist estetiğin hakimiyetine rağmen, birçok evin yerel stratejileri koruduğunu ve bu da melez bir tasarım yaklaşımını yansıttığını göstermektedir. Bulgular, gelenek, iklim bilinci ve modernizmin bir arada varlığını vurgulamakta ve sürdürülebilir mimari miras hakkında yeni içgörüler sunmaktadır.</p
Data-Driven Hybrid Approach Using Hyperparameter-Optimized Ensemble and Explainable Machine Learning for Assessing Pyrolysis Efficiency of Waste Tires
No full textPredicting pyrolysis oil yield from waste tires is a complex challenge due to the nonlinear interactions between feedstock composition and process parameters. Therefore, this study suggests the use of Decision Tree, Linear Regression, and XGBoost models to create an interpretable machine learning framework to estimate pyrolysis oil yield based on key features such as pyrolysis temperature, hydrogen, oxygen, nitrogen, volatile matter concentrations, and ash content. As a result, XGBoost outperformed the other models, with R2values of 0.965 (training) and 0.914 (testing), low root mean squared errors, and low mean absolute percentage errors. Furthermore, the Shapley Additive ExPlanations study showed that pyrolysis temperature and oxygen concentration were the most important factors. In contrast, Local Interpretable Model-Agnostic Explanations revealed that oxygen was the most important factor in individual forecast cases. A Monte Carlo simulation with 20,000 samples showed that the projected yield distribution had more than one mode, with pronounced peaks at 20, 35, and 48 wt %. Sobol sensitivity indices showed that hydrogen and pyrolysis temperature were the main factors affecting pyrolysis oil yield, followed by oxygen. Generally, this work offered a complete data-driven plan for predicting the efficiency of pyrolysis systems by combining accuracy, uncertainty quantification, and interpretability
Preparation and Characterization of Boron Nitride Coatingson Carbon Fibers From Functionalized Polyaminoboranes
No full textPolyaminoboranes, as inorganic analog of polyolefins, can be used to synthesize organic–inorganic hybrid ceramics, known asceramers, and are typical examples of inorganic polymers. Here, p block elements, such as boron (B), silicon (Si), and phosphorus(P) possessing polyaminoborane homopolymers, were synthesized and characterized. After the synthesis of phosphorus–boraneand amino silicon–borane complexes, polyaminoborane derivatives were obtained dehydrocoupling reaction in the presenceof Grubbs catalyst. Boron nitride–phosphorus (P–BN) and boron nitride–silicon (Si–BN)-based ceramics were obtained underpyrolysis condition using polyaminoborane precursors. To demonstrate surface coating application, carbon fiber surface wasdip-coated with polyaminoborane derivatives and pyrolyzed to get the functional boron nitride coating on the carbon fiber surface</p
Su Kirliliğine Neden Olan Organik Boyaların Borofen@MIL-101(Fe) Kompozitleri ile Gideriminin Araştırılması,
No full textInvestigation of different activation methods in peroxymonosulfate oxidation for the treatment of chemical industry wastewater
No full textThe chemical industry produces complex and toxic wastewater that is difficult to treat with traditional methods. In a pioneering effort, this study provides the first systematic comparison of peroxymonosulfate (PMS)-based advanced oxidation processes (AOPs) using four distinct activation methods—iron (Fe²⁺), heat, ultraviolet (UV), and electric current (EC)—for the treatment of this challenging wastewater. The chemical oxygen demand (COD) removal efficiency with a single PMS application was 18.0 %, which increased to 54.2 %, 41.4 %, 51.6 %, and 82.1 % with Fe/PMS, Heat/PMS, UV/PMS, and EC/PMS, respectively. Using the Box-Behnken Design (BBD) to determine optimum conditions, validation experiments yielded COD removal rates of 59.5 % for Fe/PMS, 47.5 % for Heat/PMS, 57 % for UV/PMS, and 91 % for EC/PMS. Additionally, UV254 removal rates were 83.8 %, 78.5 %, 83.0 %, and 94.5 %, respectively. The treatment costs were calculated as 4.66 €/kg COD for Fe/PMS, 2.60 €/kg COD for Heat/PMS, 2.40 €/kg COD for UV/PMS, and 0.43 €/kg COD for EC/PMS. Among the methods compared, the EC/PMS system emerged as the most efficient and cost-effective process, achieving a remarkable 91 % COD removal at a minimal cost. These findings confirm that the activator type has a strong impact on the performance of PMS-based AOPs and highlight the utility of BBD in optimizing these processes
EŞİK ALTI DEPRESYONU OLAN GENÇ YETİŞKİNLERDE POZİTİF PSİKOTERAPİ ODAKLI YAŞAMA BAĞLANMA PROGRAMININ İNTİHAR OLASILIĞINI VE DEPRESYON BELİRTİLERİNİ AZALTMADA ETKİNLİĞİ: PİLOT ÇALIŞMA
No full textBu çalışma, geliştirilen Pozitif Psikoterapi temelli grupla psikolojik danışma programının, eşik altı depresyonyaşayan genç yetişkinlerde depresyon semptomları ve intihar olasılığını azaltma, aynı zamanda yaşamısürdürme nedenlerini artırma konusundaki etkinliğini incelemektedir. Pozitif Psikoterapi kuramsalçerçevesine dayanan müdahalede, umut, güven ve başarı gibi olumlu kapasitelerin etkinleştirilmesi, yaşamenerjisi dengesini ve çatışma çözme becerilerini iyileştirilmesi ile psikolojik dayanıklılığın ve iyi oluşungüçlendirilmesine odaklanmıştır. Araştırma, eşdeğer olmayan kontrol gruplu yarı deneysel desenleyürütülmüştür. Katılımcılar, gönüllülük esasına göre pilot veya kontrol gruplarına yerleştirilmiştir.Programın uygulanabilirliğini ve ilk etkilerini değerlendirmek amacıyla 14 genç yetişkin ile bir pilot çalışmagerçekleştirilmiştir. Pilot grubu 6 kadın ve 1 erkekten, kontrol grubu ise 7 kadından oluşmuştur. Pilotgrubunun yaş ortalaması 21.14 (SS = 1.77), kontrol grubunun yaş ortalaması 22 (SS = 2.58) olarakbelirlenmiştir. Ön test ölçümlerinde gruplar arasında anlamlı bir fark bulunmamıştır. Ancak müdahale sonrasıson testte, Beck Depresyon Ölçeği puanlarında pilot grup lehine anlamlı ve büyük etkili bir düşüşgözlenmiştir (t(12) = -2.21, p = .048, Cohen’s d = -1.18). Benzer şekilde, Hasta Sağlık Anketi-9 puanları(t(12) = -2.97, p = .012, Cohen’s d = -1.59) ve İntihar Olasılığı Ölçeği puanları (t(12) = -2.34, p = .038,Cohen’s d = -1.59) pilot grup lehine anlamlı ve büyük ölçüde azalmıştır. Yaşamı Sürdürme NedenleriEnvanteri puanlarında ise pilot grup lehine bir artış olmasına rağmen fark istatistiksel olarak anlamlıbulunmamıştır. Bu değişken için p değerinin istatistiki anlamsızlığı katılımcı sayısının küçük olmasındankaynaklanıyor olabilir. Buna rağmen, pilot grubundaki yaşamı sürdürme nedenleri envanteri puanlarındakiartışın klinik anlamda değerli olduğu söylenebilir. Pilot çalışmanın ardından programda, ana çalışmadadenenmek üzere küçük ölçekli revizyonlar yapılmıştır. Pilot çalışma sonuçları, programın depresyon veintihar olasılığı üzerinde güçlü ve önleyici bir etkisi olabileceğini göstermiştir. Bu sonuçlar, PPT temelliyaşama bağlanma programının genç yetişkinlerde önleyici ruh sağlığı müdahalesi olarak umut vadedici birpotansiyel taşıdığına işaret etmektedir.</p
Nonlinear finite element evaluation of the seismic performance of the historic ayvat masonry weir
No full textA nonlinear seismic assessment of the 18th-century Ayvat masonry weir was performed by integrating three-dimensional finite-element (FE) modeling with Ground-Penetrating Radar (GPR) surveys. A detailed ABAQUS model of approximately 70000 continuum elements was developed and calibrated using laboratory-measured stone-mortar properties and GPR-derived foundation profiles. Nonlinear time-history analyses were carried out under Turkish Earthquake Code (TEC-2018) hazard levels DD1 (2%/50 yr) and DD2 (10%/50 yr) for both principal-axis and 45 degrees-rotated records. Under the 45 degrees-rotated DD1 record (EQ1R), crest-to-base displacements reached up to 0.30 m, and the isolated local maximum damage parameter (PEMAX*) reached 0.47. In contrast, under the 45 degrees-rotated DD2 record (EQ2R), maximum displacements remained below 0.01 m and PEMAX* did not exceed 0.14, thereby preserving global stability while inducing residual strains at the abutments. Stress concentrations were consistently detected at material discontinuities and joint zones. Based on these results, targeted retrofitting measures, including joint reinforcement and localized strengthening, are recommended to ensure the structural safety and preserve the heritage integrity of historic masonry weirs
Investigation of a Cutting Slope in a Weak Sandstone Using Deterministic and Reliability Analysis Zayıf Kumtaşı BiriminAçılan BiŞevin Deterministik GüvenilirliAnali leri ile İncelenmei
No full textThis article aims to investigate the reliability of slopes opened in weak rocks and to provide insight into the design of rock slopes. For this purpose, a cut slope opened in the Trakya Formation on a highway route was examined with deterministic and reliability analyses. Based on the engineering geology and rock mechanics data obtained within the scope of the project, assuming that the probable slip of the highway slope examined would develop in the form of a wedge, deterministic stability analyses were performed using the Hoek-Brown and Mohr-Coulomb failure criteria and Janbu and Generalized Limit Equilibrium Method for different disturbance conditions. In the reliability analyses, stability analyses were performed with the First Order Reliability Method, First Order Second Moment Method, and Monte Carlo Simulation for the probable slip wedge considered. The probability and reliability functions used in these analyses, which were performed using an algorithm developed in Python, were obtained from the open-source OpenTURNS library. For the reliability assessment of the considered rock slope, shear strength parameters, crack water depth ratio, and horizontal earthquake acceleration were considered as stochastic variables. Probabilistic properties of shear strength parameters were obtained based on field and laboratory data of the Trakya Formation. Deterministic analyses have demonstrated that rock mass properties and calculation approaches have a significant impact on slope stability. Probabilistic stability analyses provided the necessary results for design and evaluation purposes, such as failure probability or reliability index
Bridging the Gap: Teachers’ Challenges and Solution Strategies in Immigrant Student Education
No full textThe social integration and academic achievement of immigrant students significantly influence not only their individual futures but also their successful integration into the host society. It becomes essential for teachers and educational institutions to develop effective strategies for immigrant students to ensure the inclusivity and sustainability of the education system. In this context, the aim of this study is to identify the challenges faced by teachers in the education of immigrant students and to develop solution proposals for these challenges. The study employed phenomenological design, one of the qualitative research methods. The study group consisted of 16 teachers working in public schools located in the Esenyurt district of İstanbul. Participants were selected using criterion sampling and snowball sampling techniques. Data were collected through semi-structured interviews and analysed using content analysis. The findings revealed that teachers encountered difficulties related to lesson planning and implementation, language barriers, cultural differences, individual learning needs, social adaptation to the classroom and school environment, as well as communication with parents. In the research, teachers proposed solutions aimed at enhancing social cohesion, improving the language skills and academic performance of immigrant students, strengthening cooperation with families, and promoting respect for cultural diversity. Based on the research findings, a set of recommendations has been presented to enhance the educational experiences of foreign students who have migrated and to minimize the challenges encountered by teachers. </p