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Citation - WoS: 1
Citation - Scopus: 1
Deep Learning-Based Covid-19 Detection Using Lung Parenchyma Ct Scans
(Springer international Publishing Ag, 2022) Kaya, Zeynep; Kurt, Zuhal; Koca, Nizameddin; Cicek, Sumeyye; Isik, Sahin
During 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.
Citation - WoS: 2
The Limit q-bernstein Operators With Varying q
(Springer international Publishing Ag, 2019) Almesbahi, Manal Mastafa; Ostrovska, Sofiya; Turan, Mehmet
[No Abstract Available]
Citation - WoS: 27
Citation - Scopus: 41
Ux 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, Amelie
This 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.
Citation - Scopus: 1
Online Shopping Web Sites' Perceived Usability: a Case Study With Turkish Shopping Related Web Sites
(Springer international Publishing Ag, 2021) Demirci, H. Merve; Merve Demirci, H.
Using 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.
Scale Up Internet-Based Business Through Distributed Data Centers
(Springer international Publishing Ag, 2015) Yu, Liguo; Mishra, Alok; Mishra, Deepti
Distributed data centers are becoming more and more important for internet-based companies. Without distributed data centers, it will be hard for internet companies to scale up their business. The traditional centralized data center suffers the drawback of bottle neck and single failure problem. Therefore, more and more internet companies are building distributed data centers, and more and more business are moved onto distributed Web services. This paper reviews the history of distributed Web services and studies their current status through examining the distributed data centers of several top Internet companies. Based on the study, we conclude that distributed services, including distributed data centers, are the key factors to scale up the business of a company, especially, an internet-based company.
Citation - WoS: 2
Citation - Scopus: 2
A 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, Ahmet
Red 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.
Ermenek Mine Accident in Turkey: the Root Causes of a Disaster
(Springer international Publishing Ag, 2019) Ozturk, Ibrahim; Mevsim, Ridvan; Kinik, Ayca
Mining 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.
Embryo Spatial Model Reconstruction
(Springer international Publishing Ag, 2020) Dirvanauskas, Darius; Maskeliunas, Rytis; Raudonis, Vidas; Misra, Sanjay
Time lapse microscopy offered new solutions to study embryo development process. It allows embryologist to monitor embryo growth in real time and evaluate them without interfering into their growth environment. Embryo evaluation during growth process is one of the key criteria in embryo selection for fertilization. Live embryo monitoring is time consuming and new tools are offered to automate part of process. Our proposed algorithm gives new possibilities for embryo monitoring. It uses embryo images which are taken from different embryo layers, extracts embryo cell features and returns metrical evaluation to compare different embryos. High number of extracted features shows embryo fragmentation. Other tool whichwe present is spatial embryo model. Features extracted from embryo layers are combined together to spatial model. It allows embryologist to examine embryo model and compare different layers in one space. The obtained spatial embryo model will be later used to develop new algorithms for embryo analysis tasks.
Citation - WoS: 3
Citation - Scopus: 5
Users' Behavioral Strategies Toward Mobile App Problems: Fight or Flight
(Springer international Publishing Ag, 2019) Inal, Yavuz; Hacaloglu, Tuna
In this paper, we identify two distinct behavioral strategies for dealing with problems encountered in the use of mobile apps - fight or flight. In the fight strategy, individuals do not give up using an app when faced with a problem; rather, they experiment with different ways to cope with that problem, whereas the flight strategy refers to the user's decision to uninstall an app when they encounter a problem and/or their intention to use an alternative app. These strategies were identified from an analysis of documents, which forty-two users reported, and can be used to understand how users deal with encountered problems. The participants were asked to use a mobile app of their choice for one week and report the behavioral strategies they utilized to counter problems they experienced. According to the findings obtained from content analysis, the most reported complaints concerned the categories of interface design, functional error, feature request, and feature removal. The participants who complained about functional errors, frustrating features, and slow application speed stopped using the app (flight behavior) whereas those that were dissatisfied with the interface, a missing feature or the content of the app continued to use the app and tried to overcome the problems (fight behavior).
Citation - WoS: 1
A Statistical Analysis of Process Abnormalities in Slab Casting
(Springer international Publishing Ag, 2018) Keskinkilic, Ender
Continuous 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.

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