WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7150
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Article Citation - WoS: 2Citation - Scopus: 3Air Density Calculation at High Altitude Locations for Wind Energy Use: the Alpines Validation(Taylor & Francis, 2023) Bingöl, FerhatAtmospheric air density has an essential role in the energy production of wind turbines. It is directly proportional to the power taken out from the airflow. The common practice at a planned wind farm location is to measure atmospheric parameters and calculate the air density as monthly and yearly averages based on the International Committee for Weights and Measures (CIPM). After that, the reference point is used to calibrate spatial data to study the siting of wind turbines at a large spatial domain of interest using an engineering method based on only temperature and elevation a.m.s.l. The engineering method is also employed with only temperature and elevation data when there are no pressure and relative humidity measurements. The point-to-spatial transformation is done through the simplified engineering formula, and it is known that the method is primarily valid up to (Formula presented.) a.m.s.l. Above these elevations, the engineering methods have a significant bias, up to (Formula presented.) error in estimating the air density. This bias leads to a substantial error in energy yield estimations. This study uses more than one in-situ measurement at high altitude locations to calibrate the engineering method at the Alpine Convention Perimeter. It aims to improve the calculation accuracy by calculating the pressure gradient within the region. It is found that the seasonal and yearly averaging errors can be improved by (Formula presented.) to (Formula presented.) in the air density calculation with the new approach. The method can be applied to other locations with similar conditions.Article Citation - WoS: 11Citation - Scopus: 10Redefining methods for augmenting lactic acid bacteria robustness and phenyllactic acid biocatalysis: Integration valorizes simplicity(Taylor & Francis, 2022) Meruvu, HarithaThe production of phenyllactic acid (PLA) has been reported by several researchers, but so far, no mention has been made of augmented PLA production using an orchestrated assembly of simple techniques integrated to improve lactic acid bacteria (LAB) metabolism for the same. This review summarizes sequentially tailoring LAB growth and metabolism for augmented PLA catalysis through several strategies like monitoring LAB sustenance by choosing appropriate starter PLA-producing LAB strains isolated from natural environments, with desirably fastidious growth rates, properties like acidification, proteolysis, bacteriophage-resistance, aromatic/texturing-features, etc.; entrapping chosen LAB strains in novel cryogels and/or co-cultivating two/more LAB strains to improve their biotransformation potential and promote growth dependency/sustainability; adopting adaptive evolution methods designed to improve LAB strains under selection pressure inducing desired phenotypes tolerant to stress factors like heat, salt, acid, and solvent; monitoring physico-chemical LAB fermentation factors like temperature, pH, dissolved oxygen content, enzymes, and cofactors for PLA biosynthesis; and modulating purification/downstream processes to extract substantial PLA yields. This review paper serves as a comprehensive preliminary guide that can evoke a strategic experimental plan to produce industrial-scale PLA yields using simple techniques orchestrated together in the pursuit of conserving time, effort, and resources.Article Citation - WoS: 3Citation - Scopus: 3For Whom the Bell Tolls? Towards a Flexible Concept of Authenticity for Religious Heritage Buildings in Political Conflict Zones–case of Northern Cyprus(Taylor & Francis, 2022) Saifi, Yara; Yüceer, Hülya; Hürol, YoncaThis article discusses the possibility of developing an understanding of the concept of authenticity through the understanding of authenticity in architectural terms, specifically religious heritage buildings in areas of political conflict. Although authenticity has been a continuous subject of debate in the field of heritage studies, however, we argue that difficulties in coming to terms with its application in areas of conflict are still persistent. The study uses the case study of the Agios Synesios Church in North Cyprus, built around the Twelfth century, and is still in use by the Greek Cypriot minorities who continued to live on the island following its division in 1974 and the forced displacement of both Turkish and Greek Cypriot communities to either part of the island. Based on observation of the church and its surrounding context, the research shows that coming to terms with authenticity is problematic for the church since the prolongation of the Greek Cypriot way of life has been compromised due to political fluctuations. The argument suggests that once the authenticity of a religious building is assessed as a heritage asset, a flexible concept of authenticity is essential to consider in areas of political conflicts especially when its original context no longer exists.Article Citation - WoS: 2Citation - Scopus: 3Integration of Archaeological Heritage in Metropolitan City Centres With Urban Life: Agora of Smyrna(Taylor & Francis, 2022) Çalışkan, Merve; Hamamcıoğlu Turan, MineArchaeological sites located in metropolitan city centres in Turkey are subjected to diverse interventions. However, they are mostly isolated from the rest of the historical environment and become alienated from urban life. The aim is to identify an integration framework for archaeological sites in metropolitan city centres with contemporary urban life. A case study approach is employed, focusing on the Agora of Smyrna in İzmir, Turkey. Literature review on the case and similar cases, analysis of similar cases, literature review on integration criteria, survey, and a Delphi study to understand expert opinion were carried out. As a result, improving the quality of urban life and the good reputation of Agora’s vicinity, and the presentation, management, and usage of Agora itself support its integration. Nevertheless, the ‘presence of public concern for the conservation of the site’ is still the most important for the integration of the Agora with urban life.Article Citation - WoS: 3Citation - Scopus: 3Computation Time Reduction of Pcm Melting Process by Changing Modeling Parameters(Taylor & Francis, 2022) Demirkıran, İsmail Gürkan; Çetkin, ErdalThis study can be considered as a helpful reference for whom endeavor to boost the computation efficiency of the PCM melting process. Researchers sacrifice accuracy to decrease computation time since computational fluid dynamics (CFD) solutions of PCM melting processes require comparatively very long time, i.e., from hours to days or weeks, depending on the system geometry. The present study compares the approaches recommended in the literature in terms of their influence on computation time reduction and accuracy. A horizontally finned tube LHTES unit is modeled in 2-D space using ANSYS Fluent, the most common commercial CFD software for the considered problem in the literature. The outcomes obtained from the attempts to boost the computation efficiency are as follows: adaptive time step size approach causes 72% enhancement in computation time (from 90 hours to 25 hours), frozen flux algorithm and constant thermophysical properties have almost no influence on computation time. Even though low convergence criteria and neglecting natural convection reduces computation time drastically, the errors in accuracy are not in acceptable level.Article Citation - WoS: 2Citation - Scopus: 3The Green-Tao Theorem and the Infinitude of Primes in Domains(Taylor & Francis, 2022) Göral, Haydar; Özcan, Hikmet Burak; Sertbaş, Doğa CanWe first prove an elementary analogue of the Green-Tao Theorem. The celebrated Green-Tao Theorem states that there are arbitrarily long arithmetic progressions in the set of prime numbers. In fact, we show the Green-Tao Theorem for polynomial rings over integral domains with several variables. Using the Generalized Polynomial van der Waerden Theorem, we also prove that in an infinite unique factorization domain, if the cardinality of the set of units is strictly less than that of the domain, then there are infinitely many prime elements. Moreover, we deduce the infinitude of prime numbers in the positive integers using polynomial progressions of length three. In addition, using unit equations, we provide two more proofs of the infinitude of prime numbers. Finally, we give a new proof of the divergence of the sum of reciprocals of all prime numbers.Article Characterization of Yellow Patina on Stone Surfaces by Instrumental Analysis Including Libs(Taylor & Francis, 2022) Badur, Fulya; Aras, Nadir; Yalçın, Şerife; Böke, HasanYellow patina formed on the stone surfaces of historical buildings, monuments, and archaeological structures due to weathering is considered a value of the building in the conservation of cultural heritage studies. Although yellow patina layers can be easily distinguished on white marble surfaces, it is not possible to distinguish them on the yellow travertine surfaces with the naked eye. It should be taken into account in yellow travertines as well as marble surfaces before conservation treatments of the stone. In this study, mineralogical and chemical compositions and the thicknesses of yellow patina layers formed on yellow travertine and marble surfaces in Aizanoi, Aphrodisias, and Hierapolis archaeological sites in Turkey were analyzed in order to constitute a conservation approach in the archaeological sites. In this respect, XRD, FT-IR, SEM-EDX, and LIBS were used in the determination of compositions and thicknesses of yellow patina. Although LIBS analysis is a more convenient method to investigate patina layers on stone surfaces, this technique is not as well known as the others. Yellow patina layers contained calcium oxalate in the form of whewellite (CaC2O4.H2O). Their thicknesses were between 15 and 100 μm and should be protective against weathering on travertine and marble surfaces. Highlights LIBS analysis seems to be the most convenient micro-destructive method to estimate the thickness of the yellow patina layers on the marble and yellow travertine surfaces. The determination of the thickness of the yellow patina is critical to keep irreversible cleaning interventions, especially for the yellow travertines due to their similar colors. Yellow patina is mainly composed of calcium oxalate with clay minerals and organic compounds.Article Citation - WoS: 7Citation - Scopus: 10The Computational Approach To Predicting Wear: Comparison of Wear Performance of Cfr-Peek and Xlpe Liners in Total Hip Replacement(Taylor & Francis, 2022) Alpkaya, Alican Tuncay; Mihçin, ŞenayWear on articulating bearing surfaces is a key factor causing revision in total hip replacement (THR). Wear debris that releases particles from bearing surfaces might result in adverse soft tissue reactions requiring revision surgeries. In this study, a comprehensive computational wear model based on the Archard wear equation was performed to investigate the wear performance under a three-dimensional (3D) physiological gait cycle, mimicking a normal walking condition (5 million cycles). The study shows that the accuracy of the model is highly dependent on the mesh convergence, the wear fraction, and the scaling factor. The simulations were run to provide a vast amount of detail for the reproducibility of the work. Cobalt chromium (CoCr) on cross-linked polyethylene (XLPE) and CoCr on carbon-fiber-reinforced polyether ether ketone (CFR-PEEK) prototype models were created in silico. The volumetric wear rates for CoCr-on-XLPE were calculated as 0.2989 (Formula presented.) for CoCr head and 21.0271 (Formula presented.) for XLPE liner, while for CoCr-on-CFR-PEEK they were 0.3484 (Formula presented.) for CoCr head and 1.8476 (Formula presented.) for CFR-PEEK liner. When compared to in vivo and in vitro studies, the wear patterns of these two prototypes are consistent with those of the conventional polyethylene liners in the literature. Although the volumetric wear rate of the CFR-PEEK liner is about 11 times lower than the counterpart of XLPE in MoP implants, the wear rate of CoCr was higher when compared to its use with XLPE. Therefore, CFR-PEEK articulating against orthopa\edic metals may not be as good an alternative as XLPE, due to higher indicative metallic wear. This detailed computational wear modeling methodology could be utilized in design improvements of implants.Article Citation - WoS: 30Citation - Scopus: 33Targeting the Panoptosome With 3,4-Methylenedioxy Reduces Panoptosis and Protects the Kidney Against Renal Ischemia-Reperfusion Injury(Taylor & Francis, 2022) Uysal, Erdal; Dokur, Mehmet; Küçükdurmaz, Faruk; Altınay, Serdar; Polat, Sait; Batçıoğlu, Kadir; Sezgin, EfeObjectıves: The objectives of this study were a) to investigate the effect of targeting the PANoptosome with 3,4-methylenedioxy-β-nitrostyrene (MNS) on PANoptosis in the Renal ischemia-reperfussion (RIR) model b) to investigate the kidney protective effect of MNS toward RIR injury. Methods: Thirty-two rats were divided into four groups randomly. The groups were assigned as Control, Sham, DMSO (dimethyl sulfoxide) and MNS groups. The rats in the MNS group were intraperitoneally given 20 mg/kg of MNS 30 minutes before reperfusion. 2% DMSO solvent that dissolves MNS were given to the rats in DMSO group. Left nephrectomy was performed on the rats under anesthesia at the 6th hour after reperfusion. Glutathione peroxidase (GPx), malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD) and 8-Okso-2′-deoksiguanozin (8-OHdG) levels were measured. Immunohistochemical analysis, electron microscopic and histological examinations were carried out in the tissues. Results: Total tubular injury score was lower in the MNS group (p < 0.001). Caspase-3, Gasdermin D and MLK (Mixed Lineage Kinase Domain Like Pseudokinase) expressions were considerably decreased in the MNS group (p < 0.001). Apoptotic index (AI) was found to be low in the MNS group (p < 0.001). CAT and SOD levels were higher in the MNS Group (p = 0.006, p = 0.0004, respectively). GPx, MDA, and 8-OH-dG levels were similar (p > 0.05) in all groups. MNS considerably improved the tissue structure, based on the electron microscopic analysis. Conclusıons: Our results suggested that MNS administrated before the reperfusion reduces pyroptosis, apoptosis and necroptosis. These findings suggest that MNS significantly protects the kidney against RIR injury by reducing PANoptosis as a result of specific inhibition of Nod-like receptor pyrin domain-containing 3 (NLRP 3), one of the PANoptosome proteins.Article Citation - WoS: 3Citation - Scopus: 4Partial Austenitisation and Tbf Steel Composed of Ferrite, Bainitic Ferrite, and Austenite(Taylor & Francis, 2022) Erişir, Ersoy; Bilir, Oğuz Gürkan; Sözer, Yunus Emre; Ararat, Özge; Davut, KemalA TRIP-aided bainitic-ferritic (TBF) steel with a chemical composition of Fe-0.19C-1.7Mn-1.09Si-0.51Al-0.05Nb (wt-%) was partially austenitised from a hot-rolled martensitic initial microstructure. After the hot rolling, the martensitic specimens were reheated to different intercritical temperatures and then austempered at 350 degrees C. Thus, the effect of the initial microstructure of TBF steel on intercritical austenite formation during partial austenitisation was studied. The microstructures were investigated by scanning electron microscopy and electron backscatter diffraction (EBSD), and the tensile properties were tested. Microstructural observations revealed that a final microstructure of fine ferrite, bainitic ferrite, and retained austenite can be obtained. The steel partial austenitised at 770 degrees C showed a good combination of ultimate tensile strength and total elongation.
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