Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Conference Object Redundancy resolution options for the twin-it-romans robotic hybrid manufacturing system(Springer Science and Business Media B.V., 2025) Gündüz, G.M.; Dede, Mehmet İsmet Can; Kiper, Gökhan; Schmitz, M.; Corves, B.The Twinnig Iztech in Robotics Manufacturing System (TWIN-IT-ROMANS) project funded by EU Horizon -Widera-2023-Access-02-01 aims to develop a hybrid manufacturing system that can perform additive and subtractive manufacturing processes and inline quality control using a robotic system. The system will incorporate a 6-degree-of-freedom robot arm and a positioner with 2-degree-of-freedom, which will operate synchronously. This manipulation system is to be designed for performing different manufacturing operations with different degrees-of-freedom requirements. In order to reveal alternative trajectory planning scenarios for this system, this paper presents an initial review of redundancy resolution approaches for kinematically redundant robotic manipulators. First, the four main approaches for redundancy resolution techniques are introduced. Then main studies on energy minimization and stiffness maximization for kinematically redundant robotic manipulators are reviewed. Similar or new approaches are planned to be generated and implemented for the redundant system for hybrid manufacturing. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2025.Article Can Fish Kills in Izmir Bay Be Explained With Satellite Image Analysis(Osman Orhan, 2025) Elçi, Sebnem; Erdem, Ahmet Adnan; Şekerci, HalilMotivated by a significant environmental crisis that emerged, where large numbers of dead fish washed ashore in İzmir Bay in the summer of 2024, this study aims to analyze the spatial and temporal dynamics of water quality in the inner bay prior to this incidence. By calculating indices such as NDCI, SABI, and UWQV, and correlating them with climatic data (air temperature, wind speed and relative humidity), this research seeks to document the occurrence and drivers of algal blooms in the bay using Landsat 8 and Sentinel-2 satellite data from 2017 to 2025. This is the first comprehensive study conducted for İzmir Bay that investigates the relationships between water quality indices and climatic variables. It also incorporates aerial analysis of the inner bay to provide a broader spatial perspective. A customized code using Python is developed for this study to independently download and analyze raw satellite data with respect to defined corrections/masks. The results of eight years of analysis indicated that critical conditions arise every summer with air temperatures reaching 40 degrees in the study area. Estimated aerial averaged NDCI index and Chl-a concentration values show a strong positive correlation with air temperature, particularly in the Spearman’s rank correlation (rs = 0.67 and 0.62 respectively), indicating a significant relationship between these parameters. Aerial distribution of the indices for the selected critical dates also revealed a significant increase in estimated Chl-a levels during the summer months, specifically in the regions determined from the risk maps produced as a result of this study. The areas with the greatest vulnerability coincide where Poligon, Ilıca streams in the south and Bostanlı and Çiğli streams in the north discharging into the bay. It is recommended that any planned external intervention methods for managing algal blooms should start with these highly vulnerable areas as presented by this study.Article 21st Century Urban Aesthetics in the Post Critical Age: Sanart Publication(Istanbul Teknik Universitesi, Faculty of Architecture, 2025) Kök, S.; Akpinar, İ.This research problematized the relationship between human and the built environment in the 21st century, which it describes as post-critical, and examined the relationship between them in a theoretical framework through aesthetics. Within this framework, it has analyzed selected articles from the proceedings book published by SANART (Association of Aesthetics and Visual Arts). This study has defined aesthetics as a way of relating human beings to their environment. It redefined holistic aesthetic thought through approaches that focus on uncertain, porous, relational boundaries and social processes. With new perspectives that reject the dualism of subject and object, the process associated with the concepts of movement and becoming have been conceptualized through the process of urban experience from the perspective of Manuel DeLanda. This study has analyzed the urban discourses presented in SANART publications with a focus on ’movement’. It has interpreted these movements as a feature of the built environment as it is shaped by the capacities of bodies and space. It has argued that a movementoriented evaluation of urban aesthetics would further the development of the critical field. © 2025, Istanbul Teknik Universitesi, Faculty of Architecture. All rights reserved.Article Citation - WoS: 2Citation - Scopus: 3Evaluation of Hydro-Geochemical Processes Controlling Groundwater Quality in Balkh Center (Mazar-e-Sharif) Northern Afghanistan(Elsevier, 2025) Farahmand, Asadullah; Zaryab, Abdulhalim; Ameri, Nasrullah; Ali, Shakir; Eqrar, Mohammad NaimBackground: Groundwater in Afghanistan stands as the predominant water source employed for potable consumption, household utilization, irrigation, and industrial applications. Major cities of Afghanistan are largely dependent on groundwater resources. However, the groundwater quality of major cities in Afghanistan, including Mazar-e-Sharif city was not investigated in detail. Objective: This study aims to conduct a comprehensive analysis of the hydrochemical characteristics of the Mazare-Sharif groundwater, identify the factors influencing groundwater quality, and evaluate the groundwater contamination sources. Methods: A total of 18 groundwater samples were collected during the dry season (June 2020) and analyzed for various physico-chemical parameters. Methods such as multivariate statistical analyses, geochemical modeling, water quality index (WQI), and spatial distribution of groundwater quality were employed to evaluate the hydro-geochemistry of the study area. Results: The results reveal that 1) The prevailing groundwater within the study area is predominantly characterized by Na-(Ca)-HCO3 and Ca-(Mg)-SO4 water types. 2) Physicochemical variables such as NO3-, F-, TDS, and SO42-exceeded the World Health Organization (WHO) safe limits in many wells. 3) Hydro-geochemical processes such as silicate weathering, cation exchange, and gypsum dissolution controls the groundwater chemistry. 4) Cl/ Br ratios reveal, that high salinity may originate from evaporitic lacustrine and evaporite deposits and found to be localized in nature. 5) The Water Quality Index (WQI) classification suggests that approximately 60 % of the groundwater samples fall into poor to very poor water quality categories, highlighting substantial public health concerns. Major contaminants like nitrate and fluoride were found to be higher than the safe limit in nearly half of the samples. Conclusion: The findings of this study hold value for decision-makers in formulating a proficient strategy for the management of groundwater resources in Mazar-e-Sharif City in achieving the UN sustainable goal (SDG) of providing sustainable water for all. Furthermore, new advanced techniques like environmental isotopes should be analyzed to evaluate groundwater hydro-chemical evolution in the future to enhance our understanding.Article Citation - WoS: 7Citation - Scopus: 6Polymeric Biomaterials for Periodontal Tissue Engineering and Periodontitis(Royal Soc Chemistry, 2024) Yuruk, Gizem; Demir, Yagmur Damla; Vural, Sevra; Kehr, Nermin SedaThe periodontium is one of the most complex tissues in the body because its structure is formed by a hierarchical combination of soft and hard tissues. Due to its complex architecture, the treatment and regeneration of damaged periodontal tissue caused by diseases is still a challenge in biomedicine. The most common disease of the periodontium is periodontitis, which occurs when the periodontium becomes infected and inflamed as a bacterial biofilm forms in the mouth. Recently, various biocompatible biomaterials made of natural and synthetic polymers have been developed for periodontal tissue regeneration or treatment due to their superior properties such as controlled drug and bioactive molecule delivery, mimicking the 3D network of tissue, biocompatibility, antibacterial and mechanical properties. In particular, biomaterials designed for drug delivery, such as hydrogels, scaffolds, films, membranes, micro/nanoparticles and fibers, and additively manufactured biomaterials have undergone in vitro and in vivo testing to confirm their potential clinical utility in periodontal regeneration and periodontitis treatment. This review explores recent advances in the use of biomaterials for the prevention and/or treatment of periodontal regeneration and periodontitis. Specifically, it emphasizes advancements in drug/biomolecule delivery and the use of additively manufactured biomaterials for addressing periodontal issues.Article Design of Sulfur Resistant Cobalt Catalysts by Boron Promotion: Atomic Scale Insights(Sakarya University, 2024) Kızılkaya, A.C.The effect of boron promotion on atomic sulfur formation by hydrogen sulfide dissociation on Co(111), flat surfaces of cobalt nanoparticles, was investigated using Density Functional Theory calculations. The results show that on clean Co(111), hydrogen sulfide dissociation proceeds fast due to low activation barriers, yielding atomic sulfur on the cobalt surfaces. Boron promotion hinders the dissociation of hydrogen sulfide due to increased activation barriers. Furthermore, boron prevents the interaction of sulfur compounds with cobalt surface atoms, as these poisons bind on boron. The findings indicate that boron is an effective promoter that can be used to design sulfur resistant cobalt catalysts. © 2024, Sakarya University. All rights reserved.Article Citation - Scopus: 1Multi-Layer Absorber Based on Plasmonic Resonances for Photovoltaic Applications at Visible Spectra(Prof.Dr. İskender AKKURT, 2024) Demirhan, Y.This paper introduces a broadband absorber based on a multilayered, double-cylindrical-shaped metamaterial, numerically characterized for its performance. The structure comprises four interacting layers that generate plasmonic resonances. CST microwave simulations were conducted to analyze its absorption characteristics. The results demonstrate that the proposed metamaterial absorber achieves 99% absorption at 847 nm frequency region and 98% absorption in the 500-1200 nm frequency region. Additionally, polarization dependency analysis confirms that the absorber performs as a perfect, polarization-independent absorber across the studied frequency range. It exhibits high absorption in both TE and TM modes and remains unaffected by polarization or variations in the incident angle. Numerical simulations reveal that the absorption performance is driven by a combination of Fabry–Perot resonance effects, localized surface plasmons, and propagating surface plasmons. In summary, the proposed metastructure demonstrates omnidirectional absorption, polarization independence, and wide-angle incident absorption. This design shows significant potential for applications in photodetectors, active optoelectronic devices, and sensors. © IJCESEN.Article Kentlerin Depreme Dirençliliğinin Bina Bazlı Bölgesel Risk Dağılımı Yöntemi İle İncelenmesi: İzmit Kenti Örneği(Afet ve Acil Durum Yonetimi Baskanligi, 2024) Kurt, Deniz Gerçek; Guven, Ismaıl Talıh; Erdogan, HakanTürkiye, yıkıcı deprem üretme potansiyeli yüksek fay hatlarının yer aldığı bir bölgede konumlanmaktadır. Tarih boyunca, Anadolu yarımadasında meydana gelen depremler büyük can ve mal kayıplarına sebep olmuştur. Bu bağlamda, nüfusun ve sanayileşmenin çok yoğun olduğu Marmara Bölgesinde deprem risk değerlendirme çalışmalarının yoğunlaşması ve gerekli önlemlerin alınması büyük önem arz etmektedir. Bu çalışmada, 6306 sayılı \"Afet Riski Altındaki Alanların Dönüştürülmesi Hakkında Kanun\" kapsamında tanımlanan binaların bölgesel deprem riski dağılımının belirlenmesi için riskli yapıların tespitine ilişkin esaslar başlığı altında öngörülen basitleştirilmiş yöntemler kullanılarak Kocaeli ili İzmit ilçesinde bulunan 19940 bina incelenmiştir. Söz konusu yöntem, hızlı sokak taraması prensiplerini dikkate alarak bölgesel deprem risk önceliklendirmesini hedeflemektedir. Saha incelemelerinden elde edilen sonuçlar, nüfus yoğunluğu ve dağılımı, acil toplanma alanı dağılımı, toplam yapı alanı gibi parametrelerle beraber değerlendirilerek İzmit ilçesinde deprem risk öncelikli bölgelerin belirlenmesine çalışılmıştır.Article Gypsophila Eriocalyx Roots Inhibit Proliferation, Migration, and Tgf-Β Signaling in Melanoma Cells(Walter de Gruyter GmbH, 2025) Azbazdar, Yagmur; Ozhan, Gunes; Helvacioglu, SelinObjectives: Melanoma is a highly malignant and serious form of skin cancer. In addition to the standard treatments, complementary approaches, including phytotherapy, are also used to alleviate symptoms and improve patient well- being. This study aims to investigate the anticancer effects of Gypsophila eriocalyx (GE), an endemic species from Türkiye, on melanoma cells. We set out to determine the efficacy of GE in inhibiting melanoma cell proliferation, migration, and growth, and to explore its underlying mechanisms. Methods: We examined the impact of GE on the prolifera- tion of two melanoma cell lines, Malme-3M and SK-MEL-28, and assessed its developmental toxicity in zebrafish em- bryos. Next, we evaluated GE’s influence on colony forma- tion and wound healing in melanoma cells, as well as its ability to induce apoptosis and affect the TGF-β/Smad signaling pathway, by measuring pathway reporter activity and target gene expression. Results: GE inhibited cell proliferation in melanoma cell lines at concentrations 104 to 488 times lower than those required for normal non-malignant L929 fibroblast cells. In zebrafish embryos, GE demonstrated developmental toxicity only at concentrations above 50 μg/mL. GE treatment significantly impaired the colony formation and wound healing abilities of melanoma cells, indicating reduced pro- liferation and migration. Moreover, GE induced apoptosis in melanoma cells and inhibited the TGF-β/Smad signaling pathway, as evidenced by decreased pathway reporter activity and target gene expression. Conclusions: This study highlights the potential of GE as a novel therapeutic agent in melanoma treatment by demon- strating its ability to inhibit tumor growth and progressionReview Citation - WoS: 1Citation - Scopus: 2Organ-On Platforms for Drug Development, Cellular Toxicity Assessment, and Disease Modeling(Tubitak Scientific & Technological Research Council Turkey, 2024) Khurram, Muhammad Maaz; Cinel, Gokturk; Yesil Celiktas, Ozlem; Bedir, ErdalOrgans-on-chips (OoCs) or microphysiological platforms are biomimetic systems engineered to emulate organ structures on microfluidic devices for biomedical research. These microdevices can mimic biological environments that enable cell-cell interactions on a small scale by mimicking 3D in vivo microenvironments outside the body. Thus far, numerous single and multiple OoCs that mimic organs have been developed, and they have emerged as forerunners for drug efficacy and cytotoxicity testing. This review explores OoC platforms to highlight their versatility in studies of drug safety, efficacy, and toxicity. We also reflect on the potential of OoCs to effectively portray disease models for possible novel therapeutics, which is difficult to achieve with traditional 2D in vitro models, providing an essential basis for biologically relevant research.