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Access status: Open Access ,
Worlds and worldings in Turkish psychedelia: Navigating belonging and contradictions
(Graduate School, 2025-09-23) Gültekin, Setenay; Tanır Özgün, E. Şirin; Beahrs, Robert O.; 409192007; Music
Worlding is an ongoing practice. It unfolds in everyday acts, sound, silence, belonging, resistance, and imagination. This thesis was written as part of that practice. While this research attempts to trace the sonic and cultural contours of Turkish psychedelia, it also questions what it means to belong to a world, to shape one, and to share it through sound. It is both an analysis and a personal inquiry between listening and worlding, theory and experience. This dissertation explores Turkish psychedelia as a multifaceted cultural phenomenon transcending temporal and spatial boundaries. Drawing on ethnographic fieldwork, sonic and performance analysis, and personal experience, the study situates Turkish psychedelic music within a broader discussion of worlding practices—how artists and audiences create, inhabit, and contest affective worlds through music. Rather than approaching Turkish psychedelia as a fixed genre or a nostalgic recreation of 1970s Anatolian rock, the research emphasizes its dynamic, conflicting, and often contradictory nature in today's global cultural circuits. Focusing on the sonic elements of songs from both the 1970s and contemporary eras, live performances, digital and written media, and the diasporic circulation of music, the dissertation explores how artists and listeners negotiate belonging, identity, and memory. Case studies of analytic song comparisons by Barış Manço and Altın Gün concerts by Elektro Hafız and the Air Anatolia Project, along with media articles about Gaye Su Akyol, support the idea that Turkish psychedelia serves as a performative space where collective feelings of attachment emerge through ambivalence, irony, and rupture. This research demonstrates how sonic elements from the past resonate through new technologies and global aesthetics, giving rise to diverse forms of worlds and worlding. Avoiding the reduction of the musical movement to cultural hybridity or essentialized identity categories, the study adopts a phenomenological and experiential approach that foregrounds ambiguity and fluidity. The study argues that Turkish psychedelia is not a fixed or easily defined genre but a space shaped by complex and layered historical and cultural complexities. In the context of Türkiye, where contradictions and tensions often mark belonging, this music opens up an affective ground in which a sense of belonging can still emerge, despite, or even through, those conflicts. Depending on how it is experienced and performed, Turkish psychedelia can carry multiple, sometimes opposing meanings: as both a form of resistance and a site of cultural surrender to global trends. Not offering clear-cut answers, the music allows for nuanced and often ambivalent engagements with identity, memory, and the world.
Access status: Open Access ,
Development of fused parameter optımızatıon algorıthm for two- and three-parameter eıgenvalue problems
(Graduate School, 2025-07-11) Özer, Hayati Ünsal; Duran, Ahmet; 509152209; Mathematical Engineering
Nowadays, one of the issues of study in science and technology is multi-parameter eigenvalue problems (MuPEPs). These problems appear in a variety of applications such as stability of delay-differential equations, the power flow equation, dynamic model updating problem, aeroelastic flutter problems, autoregressive–moving-average (ARMA) model identification and stochastic games, etc. Moreover, MuPEPs arise in a variety of applications of these types when the method of separation of variables is used to solve boundary value problems. Therefore, we focus on two- and three-parameter eigenvalue problems. These problems can be reduced to a system of generalized eigenvalue problems by the Kronecker product and so they can be solved easily. However, Kronecker product needs serious costs in time and space. Although there are some methods such as using parallel programming to significantly reduce time cost in this product, it is more appropriate to focus on numerical methods that directly solve MuPEPs. Therefore, developing numerical solutions for these problems is an important requirement. Newton's Method is considered as one of the numerical methods used to solve the multi-parameter eigenvalue problems. Although the Newton method is a successful method for the solution of MuPEPs, we sometimes encounter some troubles such as computation cost or convergence problems. Especially, we deal with the difficulties in solving MuPEPs involving large-scale dense matrices using Newton's method. In this dissertation, we propose a fused parameter optimization (fusedparopt) algorithm for two-parameter and three-parameter eigenvalue problems. Our fusedparopt algorithm is built by Newton's method as a solver, tensor Rayleigh quotient (RQ) and the steepest descent (SD) techniques. We combine them in three ways; optimizing initial eigenpairs, optimizing eigenpairs during Newton's iteration and making these optimizations together. It is called fusedparopt_SD method. In addition, there are no such theorems about the convergence of the steepest descent technique for two-parameter and three-parameter eigenvalue problems. Therefore, we propose new theorems for the convergence of the steepest descent technique on two-parameter and three-parameter eigenvalue problems. Limited-memory BFGS (L-BFGS) can be considered as an alternative method to the SD method. We also propose L-BFGS method in our fused algorithm, as an alternative to the fusedparopt_SD method. It is called fusedparopt_LBFGS method. Two-parameter eigenvalue problems are handled to see the effect our proposed methods in applications. We test the performance of our algorithms and compare them with state-of-art algorithms such as twopareigs from MultiParEig toolbox in Matlab and tensor Rayleigh quotient-Newton (RQ_N) using the coefficient matrices coming from Lamé system and simulations via randomly generated general matrices and convergence diagrams. Our algorithm can converge earlier than the state-of-art twopareigs methods. Although high-cost solutions or convergence problems are obtained with the RQ_N method, we have more effective solutions with our algorithm. We see that solutions with RQ_N method have more fluctuations and they grow up as the size of the problem increases. However, fusedparopt method improves the results with less volatility. The results obtained by the fusedparopt_LBFGS and fusedparopt_SD methods are close to each other and comparable, depending on the matrix type. Thus, we see that fusedparopt_SD and fusedparopt_LBFGS methods achieve robustness, reasonable cost and diminish divergence problem for two-parameter eigenvalue problems based on our data set. Furthermore, we improve our proposed method for some special cases. Two approaches including deterministic grid multi-start approach and random multi-start approach are proposed in order to find all different eigenvalue tuples via our fused algorithm. We apply a similarity test to validate the distinction of computed multiple eigenvectors corresponding to the eigenvalues having multiplicity greater than one. Then, we perform tests on three-parameter eigenvalue problems having different types such as non-singular or singular problems involving small-scale or large-scale matrices. We compare our proposed approaches via fusedparopt algorithm with RQ_N and with state-of-art algorithms from MultiParEig toolbox in Matlab. Also, we discuss the challenges for coefficient matrices coming from the ellipsoidal wave equation. We also propose to parallelize our fusedparopt algorithm using the advantage of the multi-start method to compute all different eigenvalue tuples more efficiently. We make an implementation for the Baer wave equation. We obtain a three-parameter eigenvalue problem after discretizion of this equation. Then we solve this problem using our fusedparopt algorithm by dynamic thread-based parallel computing on Matlab. In conclusion, advances in science and technology require the ability to deal with large-scale problems and solve them today. However, increasing the size of the problems causes more costs in the solution, such as time and memory. This case requires not only solving problems, but also focusing to reach a solution quickly and efficiently. Therefore, the proposed fused algorithms in this dissertation have the advantages of being fast, stable, robust and low memory usage in order to find all or target number of different eigenvalue tuples and the corresponding eigenvectors in multi-parameter eigenvalue problems, especially in large-scale sizes.
Access status: Open Access ,
İşçi konutundan sosyal konuta, 1840-1939 dönemi İngiltere, Almanya ve Rusya örnekleri üzerinden değerlendirme
(Lisansüstü Eğitim Enstitüsü, 2025-06-19) Önder, Zeycan; Özsoy, Fatma Ahsen; 502882045; Mimari Tasarım
Tezde konutun, kent bağlamında sorun olarak toplum gündemine gelmesi, bu sorunun temelindeki konular ve problemler, çözümü yönünde yapılmış çalışmalar, kullanıcı tipi ve konut yapısı türleri dahil, mekânsal gelişimi çok yönlü bakış açısı ve tarihsel perspektiften ele alınmıştır. Endüstri Devrimi ile ortaya çıkan üretim biçimindeki köklü değişim ve dolayısı ile aile yapısının değişimi, nüfus hareketleri, kentlerde artan işçi nüfusunun kötü yaşam koşullarının neden olduğu sağlık sorunları, Birinci Dünya savaşının toplumsal sonuçları ve ülke yönetim biçimlerinin değişimi, belirginleşen barınma sorunu ve çözümleri konusunda önemli etkiler oluşturmuştur. Bu etkilerin konut sorunu ile ilişkisi ve sorunun çözümü yönünde yapılan çalışmalar ile ortaya konan çözümlerin incelenmesi ve tartışmaya açılması amaçlanmıştır. Bugün ve geleceğe dönük olarak, ihtiyaca karşılık verebilir, konfor koşulları yüksek, iklim duyarlı, enerji verimliği yüksek, etkileşimli ve sürdürülebilir, erişebilir konuta yönelik çalışmalar için çıkış noktaları elde edilmesi, bilgi sağlaması ve rehberlik etmesi amaçlanarak, tarihsel eşikler bağlamında 19. yüzyıl ortası ile Birinci Dünya savaşı öncesi işçi konutu dönemi ile bugünkü yaygın olarak kabul gören anlamı kapsamında, herkesin ulaşabilmesi amaçlanan sosyal konutun iki Dünya Savaşı arası dönemdeki gelişimi incelenmiştir. Teknolojik değişim, savaş, sosyoekonomik, kültürel, politik değişimler ve bu süreçteki nüfus hareketleri (göç), ülke ölçeğinde farklı etkiler oluşturmuş, aynı zamanda ülkeler arası etkileşimi de sağlamıştır. Bu nedenle belirlenen dönemlerde ve seçilen üç ülke İngiltere, Almanya ve Rusya'da, konutun gelişimine yön veren unsurlar ile ülkeler arası etkileşim ayrıntılı ele alınmış ve incelenmiştir. Savaşlarla çizilen ülke sınırları, mesafe, ulaşım ve iletişim zorlukları, toplumlar ve kültürlerarası etkileşimi engellememiş, konut yapıları ve bu alandaki deneyimler, seçilen ülkelerin yönetim ve rejim farklarına rağmen birbirleri için örnek oluşturmuş, bunun sonucu konut tasarımında benzerlikler ortaya çıkmıştır. Ülkeler arası etkileşim sonucu, konut yapılarının mekân özellikleri ve örgütlenmesinde olduğu gibi bu yapılarla oluşturulan kentsel yerleşim alanları birbirinden örnek alınmak suretiyle farklı zamanlarda, farklı ülkelerde uygulama alanı bulmuş ve evrensel yaşam biçiminin ilk deneyimlerini oluşturmuştur. Kullanıcı ihtiyaçları ve yapısının mekânsal ve biçimsel yorumu olan konut mimarisi örnekleri seçilen üç ülkenin, farklı yönetim biçimleri, sosyokültürel ve ekonomik düzenleri içinde ele alınmıştır. Tez, konut mekânına odaklanırken, etki eden unsurlara geniş perspektiften bakmayı hedeflemiş, konut tasarımının öncülük ettiği kabul edilen modern mimarlık gelişmeleri ve devlet politikasının bakış açısı göz ardı edilmemiştir.
Access status: Open Access ,
Standard model and beyond standard model studies in coherent elastic neutrino-nucleus scattering
(Graduate School, 2025-09-23) Karadağ, Sevgi; Güçlü, Mehmet Cem; Deniz, Muhammed; 509182112; Physics Engineering
This thesis investigates coherent elastic neutrino-nucleus scattering (CE$\nu$NS) to test the Standard Model (SM) and constrain standard beyond Standard Model (BSM) physics. We use accelerator-based data from the COHERENT Collaboration, where CE$\nu$NS was first observed at the Spallation Neutron Source (SNS), and reactor-based data from the TEXONO Collaboration. Specifically, we analyze COHERENT's CsI(Na) and LAr datasets, which provide a multi-flavor flux at higher $q^2$, and TEXONO's n-type and p-type point-contact HPGe datasets (nPCGe--2016 and pPCGe--2025), which use a pure $\bar\nu_e$ flux with sub-keV$_{\rm ee}$ thresholds. This approach benefits the low $q^2$ and very low thresholds of the reactors for light mediators, and the higher $q^2$ and multiple-flavor fluxes of the SNS for heavier mediators and flavor-violating (FV) scenarios. The theoretical framework starts from the SM description of CE$\nu$NS. In the CE$\nu$NS regime, the nuclear weak vector charge small momentum transfer dominates at $q^2$. The axial vector contribution is spin-dependent and sensitive to unpaired nucleons, so although its contribution is small, it needs to be accounted for when evaluating new physics sensitivities. Nuclear effects are modeled via the weak charge form factor $F(q^2)$, which captures the loss of coherence at higher $q^2$, and spin dependence is modeled via spin structure functions that encode the axial vector and tensor spin responses. The tensor operator couples to both transverse and longitudinal spin components, while the axial vector operator couples only to the transverse spin contribution. The event rate predictions are obtained by applying the experiment-specific inputs, such as quenching factor to map the nuclear recoil energy to the electron equivalent energy, energy resolution, energy-dependent efficiency, analysis thresholds, and energy ranges. TEXONO's point-contact Ge detectors reaches $\sim$300 (for nPCGe) and $\sim$200 eV$_{ee}$ (for pPCGe) thresholds and has an advantage at low $q^2$; while COHERENT operates at keV-scale thresholds, it benefits from higher $q^2$ and a three-component flux $(\nu_e,\nu_\mu,\bar\nu_\mu)$. We then present constraints in three complementary frameworks: a light-mediator (simplified) model over $(m_X,g_X)$; model-independent NSI/NGI in $\varepsilon_{\alpha\beta}^{fX}$ parameter space; and exotic neutral-current couplings $\xi_X$ covering five Lorentz-invariant structures $(V,A,S,P,T)$. For all possible scenarios we present our results at $90\%$ C.L. In the light-mediator model over $(m_X,g_X)$, reactor data are most sensitive at low $q^2$, while SNS data dominate for heavier mediators. Vector terms interfere with the SM and produce degeneracy regions for both the light mediator and flavor-conserving (FC) NSI scenarios, as well as the exotic vector interaction case. Overall, CE$\nu$NS emerges as a powerful channel for BSM searches. The complementarity of reactor and accelerator based experiments (low momentum $q^2$ and pure $\bar\nu_e$ flux versus higher momentum and multi-flavor flux), and distinct interference and spin systematics enable robust constraints across $V, A, S, P, T$ interaction channels. A key contribution of this work is the first comprehensive nonstandard interactions and neutrino generalized interactions analysis of TEXONO data within the CE$\nu$NS framework, including the explicit spin-dependent nuclear formulation for the axial and tensor operators and a full detector-level treatment (quenching factor, detector resolution, efficiency, and thresholds). TEXONO pPCGe (2025) improves significantly over nPCGe (2016), reflecting lower thresholds, and better control of detector specific effects. The TEXONO-based results and the theoretical framework have been published in \textit{Physical Review D}.
Access status: Open Access ,
Comprehensive analysis of chlorination for micropollutant removal from wastewater: Method development, efficiency, and toxicity evaluation
(Graduate School, 2025-07-23) Sarıtaş Bilgin, Nilay; Pehlivanoğlu, Elif; 501142710; Environmental Sciences, Engineering and Management
This study aims to identify the limitations of conventional wastewater treatment processes in removing micropollutants and to provide a comprehensive evaluation of the effects of chlorination, as an oxidation process, on these substances. Micropollutants, including pharmaceutically active compounds, steroid hormones, endocrine-disrupting chemicals, and disinfection by-products, are detected at measurable concentrations in the effluents of wastewater treatment plants and are largely resistant to removal by conventional biological treatment processes. Therefore, their persistence in environmental matrices and potential toxicity pose significant threats to public health and ecosystem sustainability. In this context, the thesis involved the determination of concentrations of 13 selected micropollutants and 10 associated transformation products in effluent samples collected seasonally from two major urban wastewater treatment plants in Istanbul (WWTP-1 and WWTP-2). The selected compounds were chosen based on their high environmental concentrations, widespread use, and structural resistance to conventional treatment systems. Using the developed analytical method, the potential concentrations of these compounds reaching receiving environments under different seasonal conditions were determined following biological treatment. According to the findings, the lowest total micropollutant concentration in WWTP-1 was measured in the summer (25,747 ng/L), while the highest was recorded in the spring (164,620 ng/L). In the summer samples, the highest contribution came from Caffeine (12,631 ng/L), whereas in the spring samples, O-Desmethyl Naproxen (74,153 ng/L) and Caffeine (62,612 ng/L) were the most prominent compounds. In WWTP-2, the lowest total micropollutant concentration was observed in the summer (10,580 ng/L), and the highest in the winter (151,372 ng/L); during this period, O-Desmethyl Naproxen (52,731 ng/L) and Caffeine (51,998 ng/L) were identified as the dominant compounds. In the summer, the micropollutants in WWTP-2 appeared to be more evenly distributed within the total concentration profile. To enable accurate and reproducible quantification of micropollutants at ng/L levels, a solid phase extraction-based enrichment method was developed, representing a significant contribution to the literature. This method allowed for simultaneous and high-recovery determination of both parent compounds and their transformation products, even in complex wastewater matrices. Subsequently, a multi-residue analytical method based on LC-MS/MS was optimized, establishing a strong analytical foundation for future studies. Following the determination of the current status of micropollutants, chlorination experiments were conducted using a comprehensive experimental design involving four contact times (1, 30, 120, and 1440 min.), two chlorine doses (25 and 140 mg/L), and two pH levels (original pH ≈ 7and pH 10). The results revealed that micropollutants exhibited varying levels of reactivity with chlorine and that parameters such as pH, chlorine dose, and contact time played a critical role in removal efficiency. Overall, the highest removal efficiency was achieved at original pH, using 25 mg/L chlorine dose with a contact time of 1440 minutes. This finding demonstrated that higher chlorine doses do not always lead to better removal and highlighted the importance of optimizing parameters such as contact time and pH. Carbamazepine was among the most resistant compounds to chlorination, while Ibuprofen, Naproxen, and Sulfamethoxazole also persisted at elevated concentrations under certain conditions. Although Caffeine and O-Desmethyl Naproxen were removed more efficiently, their high initial concentrations continued to contribute significantly to the residual micropollutant levels after treatment. In the second part of the thesis, two antiviral drugs (Favipiravir and Oseltamivir), widely used during the COVID-19 pandemic, were evaluated in synthetic wastewater matrices for both removal efficiency and ecotoxicological impact following chlorination. This investigation also included Polyethylene microplastics, which are frequently detected in environmental samples and exhibit micropollutant-like behavior. Microplastics are considered not only passive carriers but also active components capable of modifying chemical interactions, influencing bioavailability, and altering toxicity. Therefore, this study also explored whether the presence of microplastics modified the toxic effects of chlorinated antiviral compounds. Synthetic wastewater was spiked with 50 µg/L concentrations of Favipiravir and Oseltamivir, and chlorination was performed under two chlorine doses (10 and 50 mg/L) and two contact times (30 and 120 minutes). The same experiments were repeated in the presence of 0.1 mg/L Polyethylene microplastics to assess their influence on antiviral removal. The results showed that the average removal efficiencies for Favipiravir and Oseltamivir were approximately 42% and 26%, respectively, with MPs having a significant effect only on the removal of OSE. This was attributed to electrostatic interactions that develop depending on the solution pH. Bioluminescence tests conducted with the aquatic bacterium Aliivibrio fischeri and reproduction/survival tests performed with the soil invertebrate Enchytraeus crypticus revealed that, in the presence of antiviral compounds, certain chlorination conditions led to statistically significant inhibition in the test organisms. Moreover, it was observed that not only the chlorination of antiviral compounds but also the direct chlorination of wastewater led to toxicity in both species. This finding suggests that, despite its cost-effectiveness and ease of application, chlorination may not always be an environmentally advantageous method. On the other hand, the impact of microplastics on toxicity was found to vary depending on the type of compound and environmental conditions: in some scenarios, Polyethylene intensified biological effects by increasing the adsorption of toxic compounds, whereas in others, it mitigated toxicity by reducing the bioavailability of micropollutants. These findings confirm that microplastics are not merely inert physical pollutants, but active-matrix components capable of directly influencing chemical interactions and biological responses. Furthermore, the influence of microplastics on toxicity highlights the importance of sample matrices in environmental toxicity assessments and strongly emphasizes the need to design experimental setups that closely mimic real environmental systems. In conclusion, this thesis clearly demonstrates that treatment methods such as chlorination must be evaluated not only in terms of removal efficiency, but also with respect to transformation product formation, toxicity potential, and interactions with matrix components. The developed analytical method, optimization strategies, and toxicological assessments provide a robust scientific foundation for sustainable, safe, and environmentally friendly wastewater reuse practices. This study helps bridge existing knowledge gaps on micropollutant management in Türkiye and contributes valuable insights for global advanced treatment and reuse policies.