Istanbul Technical University
Ulusal Üniversitelerarası Açık Erişim Sistemi - İstanbul Teknik ÜniversitesiNot a member yet
67356 research outputs found
Sort by
The Relationship between Street Revitalization Project and Gentrification: The Case of Talas Ali Saip Pasha Street, Kayseri, Türkiye
No full textThe concept of gentrification was first introduced by Ruth Glass in the 1960s to describe the displacement of working-class communities in urban neighborhoods. Since the 1990s, this process has become more diversified and widespread under the influence of neoliberal urban policies and globalization. In Türkiye, gentrification examples have emerged particularly in the 1980s in major cities such as Istanbul and Ankara, encompassing both residential and commercial areas as well as historic urban centers. This study aims to investigate the relationship between the Street Revitalization Project implemented on Ali Saip Pasha Street, located within the Talas Urban Conservation Area in Kayseri, and the spatial and social transformation experienced in the aftermath of the project, in relation to gentrification processes.To thoroughly analyze the transformation and gentrification dynamics observed on Ali Saip Pasha Street, qualitative research methods were employed, including in-depth and semi-structured interviews. The findings reveal that although the project led to physical improvements in the area, residential functions declined, commercial activities became dominant, and this shift resulted in the direct or indirect displacement of long-term residents. The diminishing stock of affordable housing emerged as another critical outcome of the process. When assessed through the lens of gentrification's defining criteria, it becomes evident that the revitalization efforts have played a catalytic role in triggering gentrification within the area.https://doi.org/10.63332/joph.v5i4.120
Role of Invertebrate Biological Origin in Chitin Nanocrystal’s Morphology, Chirality, and Self-Assembly
No full textThe mention of chitin often evokes the Bouligand structure, which is a unique twisted configuration featuring a uniaxial planar organization of fibers. Although a large number of studies focused on Arthropoda, the architecture of chitin in many other invertebrate phyla remains largely unexplored. Herein, we unveil the distinctive architectures of chitin in both Arthropoda and Bryozoa, offering a comparative analysis of the morphological properties of native fibers and chitin nanocrystals sourced from these divergent organisms. In stark contrast to the Bouligand architecture prevalent in Arthropoda, Bryozoa exhibits a unique spiderweb-like arrangement of nanobundle structures, exclusive to this animal group. Bryozoan chitin nanofibers have a diameter smaller than those found among arthropods. After acid hydrolysis, the bryozoan nanocrystals are shorter and have a diameter smaller than those from arthropods. Although the chitin nanocrystals formed the chiral nematic phase, in the current study with the applied methodology, this was not the case with chitin nanocrystals from the studied bryozoan species. The unique chitin nanoarchitecture observed in Bryozoa could serve as an inspiration to produce advanced materials. Their smaller chitin nanocrystals can serve as a potential alternative to those of arthropods.https://doi.org/10.1021/acs.langmuir.5c01167http://dx.doi.org/10.1021/acs.langmuir.5c01167https://cris.vtt.fi/en/publications/e3c1285a-f866-4d03-816e-bdd6a779f606https://curis.ku.dk/ws/files/513405108/role-of-invertebrate-biological-origin-in-chitin-nanocrystal-s-morphology-chirality-and-self-assembly.pd
Fuel Based Dynamic Ship Resistance Analysis of a Container Ship: An Alternative Approach to Marine Fuels
No full textIn the literature, some properties of alternative fuels, such as low volumetric density (e.g. for hydrogen) and low heating value (e.g. for methanol, ammonia and etc.) have been mentioned as a “disadvantage”. However, the precise impact of this disadvantage is not clear. To clarify this situation, in this study, 11 different alternative marine fuels have been analyzed according to fuel gravimetric energy density analysis, using fuel heating value and density value. Different scenarios have been created to see the dynamic behavior of ship resistance. According to results, alternative clean fuels can have “low ship sailing range” and “increased energy consumption per distance” disadvantages. Among the most popular fuels, range of hydrogen (H2) and ammonia (NH3) fueled ships can be 87% and 68% lower than HFO fueled ship, if fuel tank volume is not changed. Alternatively, equivalent energy can be stored in the ship to ensure same sailing range with more stored fuel mass. In this situation, consumed energy per distance is increasing for some fuels (e.g., 1% increase for ammonia).https://doi.org/10.56850/jnse.164915
Implementation of Continuous Signal Pre-Processing Methods For Segmentation
No full texthttps://doi.org/10.1109/sist61657.2025.1113930
Information theoretical approach to detecting quantum gravitational corrections
No full textAbstract In this paper, we investigate the scales at which quantum gravitational corrections can be detected in a black hole using information theory. This is done by calculating the Kullback-Leibler divergence for the probability distributions obtained from the Parikh-Wilczek formalism. We observe that as quantum gravitational corrections increase with decrease in scale, the increase the Kullback-Leibler divergence between the original and quantum gravitational corrected probability distributions will also increase. To understand the impact of such quantum gravitational corrections we use Fisher information. We observe that it again increases as we decrease the scale. We obtain these results for higher-dimensional black holes and observe this behavior for Kullback-Leibler divergence and Fisher information also depending on the dimensions of the black hole. Furthermore, we observe that the Fisher information is bounded and approaches a fixed value. Thus, information about the nature of quantum gravitational corrections itself is intrinsically restricted by quantum gravity. Thus, this work establishes an intrinsic epistemic boundary within quantum gravity.https://doi.org/10.1007/jhep02(2025)109https://dx.doi.org/10.48550/arxiv.2310.12878http://arxiv.org/abs/2310.12878https://zbmath.org/8020661https://doaj.org/article/10574b8a57694713a16e5b5cea38c451http://hdl.handle.net/1942/4556
Agile-hybrid delivery approaches for complex design and engineering projects: an integrated case study
No full textPurpose This paper presents an in-depth case study on an agile hybrid project delivery approach in the context of a complex building design problem. The study aims to understand and evaluate the effectiveness of adaptive project delivery strategies in uncertain and complex project processes where integrated and agile methods are necessary for project development. Design/methodology/approach The study employed a qualitative research design based on an instrumental case study. An agile hybrid project delivery framework was devised by combining agile and integrated project delivery methods. The interdisciplinary design and engineering tasks were recorded and evaluated with the process and product quality dimensions. The findings were reported through a thematic analysis to highlight the strategies, benefits, and challenges within the agile hybrid project experience. Findings The results from the case study suggest that the proposed agile-hybrid approach provided an adequate basis for complex design projects with changing factors, varying needs, stringent performance requirements, and integration imperatives while addressing complexity issues, project quality and stakeholder effort. The adaptive and flexible nature of the employed project delivery framework allowed for the identification of interconnected design problems, the breakdown of design tasks into manageable and interdependent sprints, and the catalysis of dynamic and efficient stakeholder interactions for improved decision-making, increased project value and collaborative processes. Parametric BIM models facilitated the robust exchange of information during iterative and incremental project development cycles. Originality/value The study introduces an unprecedented agile hybrid approach with an adaptable and integrated project delivery framework with a comprehensive real-world case study that explores various aspects of wide-range implementation. These include compliant project types, transformed stakeholder roles and responsibilities, cross-functional team building, critical uncertainty dimensions, facilitation of iterative and cyclic workflows, situated BIM use along with strategic considerations, and suitability markers. The study also offers evidence-based insights and actionable recommendations on the effective deployment of agile hybrid project delivery methods in specific AEC projects characterized by uncertainties and ongoing changes.https://doi.org/10.1108/sasbe-04-2024-012
FedAlign: Federated Learning with State Alignment for System Identification
No full texthttps://doi.org/10.1109/iccad64771.2025.1109933
Effect of Frother Type on Surface Properties and Flotation Performance of Galena: A Comparative Study of EH, PPG250, and MIBC
No full textThe selection of suitable frothers in flotation processes plays a crucial role in controlling bubble formation, foam stability, and ultimately mineral recovery. Therefore, understanding the interfacial behavior of frothers is important to optimize flotation efficiency, especially for valuable sulfide minerals such as galena (PbS). In this study, the interfacial behavior and flotation performance of different frothers in PbS flotation were investigated with a particular focus on surface tension, bubble coalescence, foam stability, and flotation recovery. A high-purity crystalline PbS sample (≈96.65% PbS) obtained from Trabzon, Türkiye, was subjected to systematic experimental analyses including surface tension measurements, critical coalescence concentration (CCC) determination, dynamic foam stability (DFS) tests using the DFA100 analyzer, and micro-flotation experiments. 2-ethylhexanol (EH), polypropylene glycol 250 (PPG250), and methyl isobutyl carbinol (MIBC) were used as frothers, while potassium ethyl xanthate (PEX) was employed as a collector. The results revealed that EH had the highest surface activity (42.67 mN/m at 1000 ppm), and the lowest CCC value (~2 ppm) compared to PPG250 (~3 ppm) and MIBC (~8 ppm). According to the micro-flotation results, the flotation recovery gradually increased with increasing frother dosage; the highest recoveries were obtained with PPG250 (99.45%), EH (98.31%), and MIBC (95.17%). PPG250 and EH achieved higher flotation performance at lower dosages compared to MIBC. These findings highlight the critical role of molecular structure and interfacial properties in the effective selection of frothers for galena flotation.https://doi.org/10.3390/min1510104
Designing a Molecularly Imprinted Polymer Sensor for Sensitive and Selective Detection of the Prostate Cancer Drug Abiraterone Acetate
No full text<title>Abstract</title> <p> This work has successfully implemented an electrochemical sensor based on molecularly imprinted polymers for the accurate and selective detection of abiraterone acetate (AA). AA serving as the template and 2-acrylamido-2-methyl-1-propane sulfonic acid acting as the functional monomer, in conjunction with other components essential for MIP formation, were used to fabricate the sensor through a photopolymerization technique, utilizing a glassy carbon electrode. Comprehensive characterizations of surface structure and electrochemical properties were conducted using scanning electron microscopy, atomic force microscopy, cyclic voltammetry, and Fourier transform infrared spectroscopy methods. Under ideal testing circumstances, the developed sensor's linearity range was determined to be between 1.0 × 10 <sup>− 12</sup> and 1.5 × 10 <sup>− 11</sup> M. The limits of detection and quantification for the sensor were established at the picomolar level, specifically 0.29 pM and 0.98 pM, respectively, demonstrating a linear response within the same concentration range when tested with commercial human serum samples. In both tablet and spiked serum samples, the relative standard deviations remained under 2.28%, and the AA recoveries varied between 97.84 and 103.83%. Additionally, a series of Density Functional Theory calculations were conducted to better understand the experimental results and clarify the interactions between the template and monomer. </p>https://doi.org/10.21203/rs.3.rs-7774003/v
Design and performance evaluation of a novel fractional order filtered PI controller for fractional order time delay systems
No full texthttps://doi.org/10.1080/00207721.2025.245111