37 results
Search Results
Now showing 1 - 10 of 37
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.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.Book Part Citation - WoS: 1Citation - Scopus: 2In What Sense an Evolution of Metropolitan Planning Actors?(Springer international Publishing Ag, 2020) Sahin, Savas Zafer; Galland, Daniel; Tewdwr-Jones, MarkThis chapter addresses the changing roles of actors in metropolitan planning considering generations of metropolitan reforms where planning strategies and policies are shaped by agents with oftentimes conflicting conceptions and agendas about metropolitan planning. We identify and examine the transformation of key metropolitan planning actors in relation to fluctuating planning styles and assess the unintended consequences associated with changing power relations. We use illustrative examples from the West and Global Southwhere ad hoc actors and constellations of actors shape metropolitan planning in different ways. The overall contribution is to provide a trajectory of the changing nature of influential actors and the interests that lie behind the redefinition and reinterpretation of metropolitan planning.Conference Object Citation - WoS: 1Citation - Scopus: 1Disseminating the Use of Sustainable Design Principles Through Architectural Competitions(Springer international Publishing Ag, 2018) Toprak, Gizem KucakSustainable architectural designs have become current issue, as in other disciplines, in architecture since 1970s because of these reasons, oil shock, global warming, to be consumed natural resources, get further away from the nature. Putting into practice and increase of awareness of sustainable architectural designs become a important topic 2000s in Turkey. It's hard to reach clear information about how much designs are carried into practice. Obtaining energy efficiency certificate for new buildings has become obligatory since 1 January 2011 and it's determined that 450,815 buildings have this certificate. But this certificate evaluates energy performance of buildings only. In fact, process of sustainable design cannot be evaluated by just energy performance analysis. Efficiently use of energy, water, building land and environment, relationship with environment and buildings, benefit/damage analysis in urban area, increase of user comfort in building come into prominence. 425 buildings obtained LEED certificate that make a comprehensive investigation. As it seen, the numbers, used above, show us, it's necessary that sustainable design principles must be disseminated and the methods, are been used, must be evaluated. This work tackles architectural competitions as a method for developing and disseminating sustainable design principles. Architectural competitions are not only didactic but also developer and independent design platform which all architects can join. The results are reached the large masses over draw up a contract, design process, evaluating the projects and discussion platform, colloquium. So that the establishment, designers, the jury and the other participants are involved in an interaction. Architectural competitions can used for development, evaluation, discussion and dissemination of sustainable design principles. The aim of this work is that evaluating how to tackle "sustainability" as a term in competitions, in 2010s and in accordance with the results, offering suggestions for disseminating the use of sustainable design principles with competitions also.Conference Object Citation - Scopus: 1Online Shopping Web Sites' Perceived Usability: a Case Study With Turkish Shopping Related Web Sites(Springer international Publishing Ag, 2021) Demirci, H. MerveUsing an online shopping website could be considered preferable to shopping from a crowded shop where one may interact with other people. The underlying reasons for this preference related to the psychology of the people; whether they are introverted or shy, or while online shopping, people may feel freer than being in a physical shop with lots of people, which may lead them to feel irritated [1]. On the other hand, the reason may relate to the websites' design and usability to make them a better option. This study aims to analyze the shopping sites' interface designs' perceived usability on users in Turkey and the relation of the websites' measured usability with the help of CogTool to make a comprehension between the findings. To reach this aim, first of all, a survey had conducted through an e-mail to choose the most preferred online shopping sites with 25 women. Afterward, one task had been decided; buying the same shoe for participants to complete to measure decided websites' usability. The usability test had been done with CogTool to the chosen websites, and a user test had been done with the ten female users out of 25 as a continuation of the first phase of the study. The study's findings show the underlying reasons for the preferences and the overlapping values between usability and user tests.Conference Object Citation - WoS: 2Citation - Scopus: 2A Study on Recovery of Iron from Red Mud by Solid State Reduction Followed by Magnetic Separation(Springer international Publishing Ag, 2020) Eray, Said; Keskinkilic, Ender; Varol, Mustafa; Topkaya, Yavuz A.; Geveci, AhmetRed mud is a waste material of the Bayer process for alumina production from bauxite ore. Red mud is generally pumped to disposal in an artificial pond which is accompanied by great land occupation and environmental issues. Many researches in different fields have been carried out to evaluate the red mud. Of these, researches on recovering valuable metals from red mud are the most successful. In this study, recovery of iron, which is the most abundant metal in red mud, was investigated. A red mud sample with 34% Fe2O3 was used. Solid state carbothermic reduction followed by wet magnetic separation was performed to recover iron. Reduction was carried out at temperatures 1000-1200 degrees C. Reduced samples were ground and subjected to wet magnetic separation. The effect of reduction temperature and grinding time were investigated on the metallization of iron and the iron content of the final concentrate.Conference Object Ermenek Mine Accident in Turkey: the Root Causes of a Disaster(Springer international Publishing Ag, 2019) Ozturk, Ibrahim; Mevsim, Ridvan; Kinik, AycaMining accidents are one of the critical safety concerns all over the world. From the general point of safety, it is important to identify human factors, especially violations, and other types of barriers with respect to the occurrence of an accident. Root Cause Analysis helps to identify the mechanism behind accidents and develop future countermeasures for prevention. In the current analysis, Ermenek Mine Accident in Turkey was evaluated by using Root Cause Analysis Tool Kit and Manchester Patient Safety Framework (MaPSaF). Safety issues were structured by using Five Whys, Fishbone Diagram, and Barrier Analysis and safety culture were evaluated by using some of the dimensions of MaPSaF. Main factors were structured by using Five Whys, Barrier Analysis, and Manchester Safety Framework. According to these main factors, fishbone diagram was constructed. In general, natural, personnel, general policy in mining industry, and management issues in mining industry were determined as main four deficiencies affecting the occurrence and consequences of the accident. These main four factors were detailed in the fishbone diagram. The results indicated the importance of including different agents in the process of mining and working in cooperation to develop necessary policies and actions. Some methodological and practical suggestions were made for safety related issues. It is important to state policies related to basin in mining by considering both economic factors and safety factors. Moreover, reports related to safety issues should be more detailed by considering individual and organizational safety culture factors.
