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Article Citation - WoS: 21Citation - Scopus: 23Best Proximity Points of Generalized Almost Ψ-Geraghty Contractive Non-Self(Springer international Publishing Ag, 2014) Aydi, Hassen; Karapinar, Erdal; Erhan, Inci M.; Salimi, PeymanIn this paper, we introduce the new notion of almost psi-Geraghty contractive mappings and investigate the existence of a best proximity point for such mappings in complete metric spaces via the weak P-property. We provide an example to validate our best proximity point theorem. The obtained results extend, generalize, and complement some known fixed and best proximity point results from the literature.Article Citation - WoS: 13Citation - Scopus: 14The Existence of Optimal Approximate Solution Theorems for Generalized Α-Proximal Contraction Non-Self Mappings and Applications(Springer international Publishing Ag, 2013) Karapinar, Erdal; Sintunavarat, WutipholIn this paper, we investigate the sufficient conditions to find a best proximity point for a certain class of non-self mappings. It is well known that optimization problems can be transformed to the problems of the existence of a best proximity point. Hence, improvement in the best proximity point theory implicitly develops the theory of optimization. Our presented results generalize, extent and improve various well-known results on the topic in the literature. In particular, we consider some applications of our results to the best proximity point theorems on a class of metric spaces endowed with an arbitrary binary relation which involves the partially ordered metric spaces.Conference Object Citation - WoS: 1A Statistical Analysis of Process Abnormalities in Slab Casting(Springer international Publishing Ag, 2018) Keskinkilic, EnderContinuous casting of slabs is conducted with two successive steel flows: first from ladle to tundish, then from tundish to mold. There are certain process abnormalities related to ladle, tundish and mold. For example, change of submerged entry nozzle (SEN) is the one encountered during steel flow from tundish to mold. Tundish exchange is the abnormality taking place due to replacement of processed tundish with the new one at rest. Another example is the flow of steel from ladle to tundish without a ladle shroud. In this study, a statistical analysis was conducted related to the process abnormalities in slab casters of a steel plant. Slab surface defects observed in slab yard was incorporated in this analysis.Conference Object Citation - WoS: 2Citation - Scopus: 2Solid-State Reduction Studies for Recovery of Iron From Red Mud(Springer international Publishing Ag, 2020) Keskinkilic, Ender; Pournaderi, Saeid; Geveci, Ahmet; Topkaya, Yavuz A.Red mud or bauxite residue can be regarded as a by-product of aluminum extraction process since it contains a significant amount of iron and some valuable elements. Therefore, the treatment of red mud has been a hot topic for some decades. Last year, the authors started a laboratory-scale project dealing with stepwise recovery of valuable elements from red mud of Seydisehir Aluminum Plant, Turkey. The first step is related to the recovery of iron and pyrometallurgical methods (solid-state reduction and smelting) are currently being performed. Nonferrous metals will then be selectively leached in the second step. In TMS 2019, the authors outlined the literature related to the smelting studies for iron recovery from bauxite residue. In the extent of the present work, a literature review relevant to the solid-state reduction studies for recovery of iron from red mud was presented.Article Citation - WoS: 13Citation - Scopus: 18On the existence of fixed points that belong to the zero set of a certain function(Springer international Publishing Ag, 2015) Karapinar, Erdal; O'Regan, Donal; Samet, BessemLet T : X -> X be a given operator and F-T be the set of its fixed points. For a certain function phi : X -> [0,infinity), we say that F-T is phi-admissible if F-T is nonempty and F-T subset of Z(phi), where Z(phi) is the zero set of phi. In this paper, we study the phi-admissibility of a new class of operators. As applications, we establish a new homotopy result and we obtain a partial metric version of the Boyd-Wong fixed point theorem.Review Citation - WoS: 3Citation - Scopus: 9An Empirical Evaluation of Software Quality Assurance Practices and Challenges in a Developing Country: a Comparison of Nigeria and Turkey(Springer international Publishing Ag, 2016) Sowunmi, Olaperi Yeside; Mısra, Sanjay; Misra, Sanjay; Fernandez-Sanz, Luis; Crawford, Broderick; Soto, Ricardo; Mısra, Sanjay; Computer Engineering; Computer EngineeringBackground: The importance of quality assurance in the software development process cannot be overemphasized because its adoption results in high reliability and easy maintenance of the software system and other software products. Software quality assurance includes different activities such as quality control, quality management, quality standards, quality planning, process standardization and improvement amongst others. The aim of this work is to further investigate the software quality assurance practices of practitioners in Nigeria. While our previous work covered areas on quality planning, adherence to standardized processes and the inherent challenges, this work has been extended to include quality control, software process improvement and international quality standard organization membership. It also makes comparison based on a similar study carried out in Turkey. The goal is to generate more robust findings that can properly support decision making by the software community. The qualitative research approach, specifically, the use of questionnaire research instruments was applied to acquire data from software practitioners. Results: In addition to the previous results, it was observed that quality assurance practices are quite neglected and this can be the cause of low patronage. Moreover, software practitioners are neither aware of international standards organizations or the required process improvement techniques; as such their claimed standards are not aligned to those of accredited bodies, and are only limited to their local experience and knowledge, which makes it questionable. The comparison with Turkey also yielded similar findings, making the results typical of developing countries. The research instrument used was tested for internal consistency using the Cronbach's alpha, and it was proved reliable. Conclusion: For the software industry in developing countries to grow strong and be a viable source of external revenue, software assurance practices have to be taken seriously because its effect is evident in the final product. Moreover, quality frameworks and tools which require minimum time and cost are highly needed in these countries.Conference Object Citation - WoS: 1Citation - Scopus: 1Deep Learning-Based Covid-19 Detection Using Lung Parenchyma Ct Scans(Springer international Publishing Ag, 2022) Kaya, Zeynep; Kurt, Zuhal; Koca, Nizameddin; Cicek, Sumeyye; Isik, SahinDuring the outbreak of the COVID-19 pandemic, it is important to improve early diagnosis using effective ways in order to lower the risks and further spread of the viruses as early as possible. This is also important when it comes to appropriate treatments and the reduction of mortality rates. In this respect, computer tomography (CT) scanning is a useful technique in detecting COVID-19. The present paper, as such, is an attempt to contribute to this process by generating an open-source, CT-based image dataset. This dataset contains the CT scans of lung parenchyma regions of 180 COVID-19 positives and 86 COVID-19 negative patients, all from Bursa Yuksek Ihtisas Training and Research Hospital. The experimental studies demonstrate that this dataset is effectively utilized deep learning-based models for diagnostic purposes. Firstly, a smart segmentation mechanism based on the k-means algorithm is applied to this dataset as a pre-processing stage. Then, the performance of the proposed method is evaluated using InceptionV3 and Xception convolutional neural networks, yielding a 96.20% and 96.55% accuracy rate and 95.00% and 95.50% F1-score, respectively. These state-of-the-art models are observed to detect COVID-19 cases faster and more accurately. In addition, the fine-tuning stage of the convolutional neural network (CNN) features sufficiently improves this accuracy rate. For these features, the support vector machine (SVM) classifier is used, resulting in remarkable 96.76% accuracy rate and 95.81% F1-score. The implications of the proposed method are immense both for present-day applications as well as future developments.Conference Object Citation - WoS: 2The Limit q-bernstein Operators With Varying q(Springer international Publishing Ag, 2019) Almesbahi, Manal Mastafa; Ostrovska, Sofiya; Turan, Mehmet[No Abstract Available]Book Part Citation - WoS: 15Citation - Scopus: 15Comparison of Hematopoietic and Spermatogonial Stem Cell Niches From the Regenerative Medicine Aspect(Springer international Publishing Ag, 2018) Kose, Sevil; Yersal, Nilgun; Onen, Selin; Korkusuz, PetekRecent advances require a dual evaluation of germ and somatic stem cell niches with a regenerative medicine perspective. For a better point of view of the niche concept, it is needed to compare the microenvironments of those niches in respect to several components. The cellular environment of spermatogonial stem cells' niche consists of Sertoli cells, Leydig cells, vascular endothelial cells, epididymal fat cells, peritubular myoid cells while hematopoietic stem cells have mesenchymal stem cells, osteoblasts, osteoclasts, megacaryocytes, macrophages, vascular endothelial cells, pericytes and adipocytes in their microenvironment. Not only those cells', but also the effect of the other factors such as hormones, growth factors, chemokines, cytokines, extracellular matrix components, biomechanical forces (like shear stress, tension or compression) and physical environmental elements such as temperature, oxygen level and pH will be clarified during the chapter. Because it is known that the microenvironment has an important role in the stem cell homeostasis and disease conditions, it is crucial to understand the details of the microenvironment and to be able to compare the niche concepts of the different types of stem cells from each other, for the regenerative interventions. Indeed, the purpose of this chapter is to point out the usage of niche engineering within the further studies in the regenerative medicine field. Decellularized, synthetic or non-synthetic scaffolds may help to mimic the stem cell niche. However, the shared or different characteristics of germ and somatic stem cell microenvironments are necessary to constitute a proper niche model. When considered from this aspect, it is possible to produce some strategies on the personalized medicine by using those artificial models of stem cell microenvironment.Conference Object Citation - WoS: 27Citation - Scopus: 41Ux Professionals' Definitions of Usability and Ux - a Comparison Between Turkey, Finland, Denmark, France and Malaysia(Springer international Publishing Ag, 2017) Rajanen, Dorina; Clemmensen, Torkil; Iivari, Netta; Inal, Yavuz; Rizvanoglu, Kerem; Sivaji, Ashok; Roche, AmelieThis paper examines the views of user experience (UX) professionals on the definitions of usability and UX, and compares the findings between countries and within different socio-cultural groups. A mixed-method analysis was employed on data gathered on 422 professionals through a survey in Turkey, Finland, Denmark, France, and Malaysia. Usability appears to be an established concept, respondents across all countries agreeing on the importance of the ISO 9241-11 definition. There is also a tendency that UX professionals attach organizational perspective to usability. UX professionals diverge when defining UX, and there are systematic differences related to socio-cultural conditions. UX professionals in Finland and France incline more towards the definition highlighting the experiential qualities, when compared to Turkey and Malaysia that incline towards the definition reflecting the ease of use, utility, attractiveness, and degree of usage. Further research should address the implications of the diverse meanings and contexts of usability and UX.
