TR Dizin İndeksli Yayınlar / TR Dizin Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7149
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Article A Survey On the Visibility Of Mosaic Heritage On The UNESCO World Heritage List(Bursa Uludağ University, 2025) Akture, Z.World Heritage Programme was launched under the auspices of UNESCO by adopting the Convention concerning the Protection of the World Cultural and Natural Heritage in 1972. 1223 cultural, natural, and mixed properties have been inscribed on the World Heritage List (WHL) from 1978 to 2024 to ensure international consideration and assistance in their preservation as patrimony of humanity. This paper offers an insight into the visibility of mosaic heritage in this corpus through a survey of references to mosaics in the Statements of Outstanding Universal Value (OUV) on the homepages of World Heritage properties at UNESCO’s website. After an introduction on the requirements for inscription on WHL, distribution of mosaics in World Heritage properties is surveyed in reference to their category, location on the globe, and setting within the property to highlight over- and under-representations, with inspiration from the current strategy of achieving a balanced representation of heritage types, chronologies-regions, and themes on WHL. Then selected “exceptions” in terms of mosaic types, locations, and periods are presented to contribute in increasing their visibility, followed by “highlights” in whose Statements of OUV the word “mosaic” is most repeated. Adopting the wholistic approach recommended in the World Heritage Programme, both sections aim to contextualise the selected examples in the overall corpus and mosaic heritage as an element forming and representing their attributes of OUV. After observing the thus exemplified variety in the mosaic heritage so far inscribed on WHL, concluding remarks highlight areas of further research to deepen the presented visibility analysis. © (2024), (). All Rights Reserved.Article Seismic Risk Prioritization of Stone Masonry Building Stock in Urla Peninsula Based on Rapid Assessment Techniques(Turkish Chamber of Civil Engineers, 2026) Karavin, Y.S.; Akdag, N.; Demir, U.This study aims to investigate seismic risk of stone masonry buildings in the Urla Peninsula, a region of historical and architectural significance within İzmir, Türkiye. A total of 100 stone masonry buildings were surveyed and documented with a focus on their architectural characteristics, including construction techniques, material types, structural configurations, and age. Data on the properties of all surveyed buildings are provided in an open-access database. Based on the survey, multiple rapid seismic performance assessment methods were applied to evaluate the vulnerability of these structures. These included: i) FEMA P-154 Rapid Visual Screening, ii) Provisions for the Seismic Risk Evaluation of Existing Buildings under Urban Renewal Law (RBTE-2019), iii) Seismic Vulnerability Index for Vernacular Architecture (SVIVA), and iv) the Masonry Quality Index (MQI). The comparative use of different methods is intended to investigate the relative influence of parameters shaping the seismic performance of the masonry building stock rather than to align their scores. The outcomes of this research are expected to contribute to the current risk mitigation efforts for stone masonry buildings in İzmir, thereby supporting regional seismic resilience planning. © 2026, Turkish Chamber of Civil Engineers. All rights reserved.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 Biquandle Power Brackets of Oriented Links(Tubitak Scientific & Technological Research Council Turkey, 2025) Gügümcü, Neslihan; Nelson, SamIn this paper, we introduce biquandle power brackets, an infinite family of invariants of oriented links containing the classical skein invariants and the quandle and biquandle 2-cocycle invariants as special cases. Biquandle power brackets are generalizations of biquandle brackets in which the values of Kauffman states also depend on the biquandle colors they admit. We provide example computations and discuss the relationship between these new invariants and the previous cases.Article Experimental Study of Evolution of Breach Resulting From Piping at Upper Part of Earth-Fill Dam(Turkish Chamber Civil Engineers, 2025) Guney, Mehmet Sukru; Tayfur, Gokmen; Bor, Asli; Okan, Merve; Dumlu, Emre; Aklık, PelinPiping and overtopping are the most important causes of earth-fill dam failure. Such dams may erode under seepage, causing a reduction in the structural strength. The aim of this study was to investigate the temporal evolution of the breach and flow rate from the breach resulting from the piping in earth-fill dams. The experiments were carried out at Hydraulics Laboratory of Civil Engineering Department of İzmir University of Economics. The dam was constructed by using a mixture consisting of 85 % sand and 15 % fine (low plasticity clay). In the first scenario a circular tunnel with a diameter of 2 cm was created along the centreline at 6 cm below the dam crest whereas in the second one it was located at the upper edge. Six cameras at different locations recorded the evolution of the progress of the breach formation. The pump flow rate was measured by magnetic flow meter, and the continuity equation was used to calculate the flow rate values from the breach. The time-varied values of the total breach areas were determined using the Gauss Area formula. The image processing method was also applied in the determination of the breach areas. The time-dependent changes of water depth in the channel were also recorded. The obtained experimental findings are presented and commented, together with the universal dimensionless curves. The failure of the dams occurred mainly because of the head cut erosion developed from downstream to upstream. When breaching started, the orifice flow was converted to open channel flow where breach bottom behaved like a broad crested weir. In the second scenario, the rigid lateral side considerably influenced the flow rate and the development of the breach. The peak flow rate corresponding to the first scenario was found approximately 2.3 times greater than that of the second one. The maximum values of all the breach parameters were reached earlier in the case of the seepage along the centerline. The ratios between the values corresponding to the first and the second scenarios were found as 3.25 and 1.75 for maximum breach areas at downstream and at upstream sides, respectively. These ratios were 2.44 and 1.37 for the average breach widths at downstream and upstream sides, respectively. A very good agreement was found between the area values obtained from Gauss area method and image processing technique, in both scenarios. This fact demonstrated that either of these two approaches can be used to determine the time-dependent breach areas. These experimental findings provide the opportunities for the calibration and validation of the numerical models used in the relevant numerical investigations. This study also offers guidance for the strategies concerning emergency action plans related to the failure of homogeneous earth-fill dams when the piping starts at upper part of the homogeneous earth-fill dams.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 progressionArticle Citation - WoS: 1Citation - Scopus: 1Investigation of Flow and Heat Transfer Performance of Gyroid Structure as Porous Media(Turkish Soc Thermal Sciences Technology, 2024) Genc, Alper Mete; Karadeniz, Ziya HaktanThere are active and passive methods used to improve heat transfer. One of the passive methods is utilising porous media with high heat transfer surface area. Porous media are divided into two groups: regular and irregular structures. One of the regular structures is triply periodic minimal surfaces (TPMS), which have been studied quite frequently recently. In this study, heat transfer and flow analysis of a Gyroid geometry, one of the most used TPMS in the literature, is investigated numerically considering the conjugate heat transfer conditions. A single porosity is considered (epsilon = 0.6), and aluminium, ceramic and PLA are selected for the heat exchanger material to examine the temperature change in the heat exchanger. To understand the different flow characteristics, Reynolds numbers are assumed to be 19.12, 95.61 and 172.09. The fluid inlet temperature is assumed to be constant at 298.15 K, and the initial temperature of the heat exchanger is assumed to be constant at 278.15 K to be consistent with the regenerative heat recovery temperature difference in ventilation standards. Nusselt numbers under different operating conditions are compared, and it is the ceramic material with low thermal diffusivity is at the highest level despite its low thermal conductivity. At the highest Reynolds number, it provided approximately 6% better heat transfer than the aluminium heat exchanger.Article Design of Sulfur Resistant Cobalt Catalysts by Boron Promotion: Atomic Scale Insights(Sakarya University, 2024) Kizilkaya, 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 - WoS: 1Citation - Scopus: 2Lacoo3 Is a Promising Catalyst for the Dry Reforming of Benzene Used as a Surrogate of Biomass Tar(Tubitak Scientific & Technological Research Council Turkey, 2024) Çağlar, Başar; Üner, DenizTar build-up is one of the bottlenecks of biomass gasification processes. Dry reforming of tar is an alternative solution if the oxygen chemical potential on the catalyst surface is at a sufficient level. For this purpose, an oxygen-donor perovskite, $LaCoO_3$, was used as a catalyst for the dry reforming of tar. To circumvent the complexity of the tar and its constituents, the benzene molecule was chosen as a model compound. Dry reforming of benzene vapor on the $LaCoO_3$ catalyst was investigated at temperatures of 600, 700, and 800 °C; at $CO_2/C_6H_6$ ratios of 3, 6, and 12; and at space velocities of 14,000 and 28,000 h–1. The conventional Ni(15 wt.%)/$Al_2O_3$ catalyst was also used as a reference material to determine the relative activity of the $LaCoO_3$ catalyst. Different characterization techniques such as X-ray diffraction, $N_2$ adsorption-desorption, temperature-programmed reduction, and oxidation were used to determine the physicochemical characteristics of the catalysts. The findings demonstrated that the $LaCoO_3$ catalyst has higher $CO_2$ conversion, higher $H_2$ and CO yields, and better stability than the Ni(15 wt.%)/γ-$Al_2O_3$ catalyst. The improvement in activity was attributed to the strong capacity of $LaCoO_3$ for oxygen exchange. The transfer of lattice oxygen from the surface of the $LaCoO_3$ catalyst facilitates the oxidation of carbon and other surface species and leads to higher conversion and yields.Article Lubricants Having Zinc Borate by Homogeneous Precipitation and Span 60 in Spindle Oil(Turkish Energy Nuclear and Mining Research Institute, 2021) Gönen, Mehmet; Alp, Burcu; Savrık, Sevdiye; Balköse, Devrim; Alp, Fatma Burcu; Balkose, DevrimNano particles of zinc borate were obtained by homogeneous precipitation method which is based on dissolving zinc borate in ammonia and precipitating it as nano particles by slow evaporation of ammonia. The synthesized zinc borates were characterized by advanced analytical techniques. Zinc borate nano particles were used as a lubricant additive to spindle oil having Span 60 dispersant. The particles were well dispersed in spindle oil as shown by optical microscopy of the oils. Four ball tests of the lubricants indicated zinc borate lowered (61.8%) the wear scar diameter significantly. The hardness of wear surfaces of test balls was reduced from 688 HV to 618 HV and presence of zinc borate particles embedded on the surface indicated a flexible skin was formed. Therefore the pressure was decreased due to increase of the contact area of the balls. The surface roughness was also decreased from 35.63 nm to 27.60 nm by the addition of zinc borate to spindle oil having Span 60. Zinc borate prepared by homogeneous precipitation technique lowered the wear of the surfaces that rub to each other.