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NFC loyal system on the cloud
(IEEE Computer Society, 2013) Coşkun, Vedat; Özdenizci Köse, Büşra; Ok, Kerem; Alsadi, Mohammed
FC (Near Field Communication) technology facilitates mobile phone usage of billions of people throughout the world that offers diverse services ranging from payment and loyalty applications to access keys for offices and houses. NFC technology is one promising technology that have adopted smart card as secure element (SE) to provide a secure area for the execution of multiple applications and storing sensitive data. In this paper, we developed a framework to integrate NFC loyal system onto the cloud. We adapted NFC mobiles together with their SE to the cloud (Infrastructure as a Service - IaaS) using Cloud Computing methodology.
Reviewing the effects of spatial features on price prediction for real estate market: Istanbul case
(IEEE, 2022-09-16) Ecevit, Mert İlhan; Erdem, Zeki; Dağ, Hasan
In the real estate market, spatial features play a crucial role in determining property appraisals and prices. When spatial features are considered, classification techniques have been rarely studied compared to regression, which is commonly used for price prediction. This study reviews spatial features' effects on predicting the house price ranges for real estate in Istanbul, Turkey, in the classification context. Spatial features are generated and extracted by geocoding the address information from the original data set. This geocoding and feature extraction is another challenge in this research. The experiments compare the performance of Decision Trees (DT), Random Forests (RF), and Logistic Regression (LR) classifier models on the data set with and without spatial features. The prediction models are evaluated based on classification metrics such as accuracy, precision, recall, and F1-Score. We additionally examine the ROC curve of each classifier. The test results show that the RF model outperforms the DT and LR models. It is observed that spatial features, when incorporated with non-spatial features, significantly improve the prediction performance of the models for the house price ranges. It is considered that the results can contribute to making decisions more accurately for the appraisal in the real estate industry.
Comparison of choreography vs orchestration based Saga patterns in microservices
(Institute of Electrical and Electronics Engineers Inc., 2022) Aydın, Şahin; Çebi, Cem Berke
Microservice Architecture (MSA) is a design and architecture pattern created to deal with the challenges of conventional software programs in terms of stream processing, highly available flexibility, and infrastructural agility. Despite the many advantages of MSA, designing isolated services using the autonomous Databases per Services paradigm is difficult. We realized that because each microservice will have its repository, ensuring data coherence between databases becomes difficult, especially in reversals, where operations transcend different sites. Distributed networked transactions and rollbacks can be efficiently handled using two-phase commitment methods in hardware virtualization using RDBMS databases. However, these approaches can't be used in micro-services with segregated NoSQL servers. Three issues have been addressed in this study: (i) investigate the implementation of event choreography and orchestration methods for the Saga pattern execution in MSA, (ii) existing reality suggestions on the saga pattern adoption and implementation besides the use cases, and (iii) introduce the disbursed transaction records and rollbacks challenges in isolated No-SQL databases with reliant collections in MSA.
Photogrammetric monitoring of an artificially generated landslide
(Copernicus GmbH, 2011-05-08) Akça, Mehmet Devrim; Gruen, Armin W.; Askarinejad, Amin; Springman, Sarah Marcella
According to pre-planned schedules, a series of two artificial rainfall events were applied to a forested slope in Ruedlingen, northern Switzerland. The experiments were conducted in autumn 2008 and spring 2009, the second of which resulted in mobilising about 130 m3 of debris. Both experiments were monitored by a photogrammetric camera network in order to quantify spatial and temporal changes. A 4-camera arrangement was used for the image acquisition. The cameras operated at a data acquisition rate of circa 8 frames per second (fps). Image measurements were made using the Least Squares image matching method, which was implemented in an in-house developed software package (BAAP) to compute 3D coordinates of the target points. The surface deformation was quantified by tracking the small (ping-pong and tennis) balls pegged into the ground. The average 3D point-positioning precision of ±1.6 cm was achieved in the first experiment and ±1.8 cm in the second experiment.
Comparison of evolutionary techniques for Value-at-Risk calculation
(Springer-Verlag Berlin, 2007) Uludağ, Gönül; Etaner Uyar, Ayşe Şima; Senel, Kerem; Dağ, Hasan
The Value-at-Risk (VaR) approach has been used for measuring and controlling the market risks in financial institutions. Studies show that the t-distribution is more suited to representing the financial asset returns in VaR calculations than the commonly used normal distribution. The frequency of extremely positive or extremely negative financial asset returns is higher than that is suggested by normal distribution. Such a leptokurtic distribution can better be approximated by a t-distribution. The aim of this study is to asses the performance of a real coded Genetic Algorithm (CA) with Evolutionary Strategies (ES) approach for Maximum Likelihood (ML) parameter estimation. Using Monte Carlo (MC) simulations, we compare the test results of VaR simulations using the t-distribution, whose optimal parameters are generated by the Evolutionary Algorithms (EAs), to that of the normal distribution. It turns out that the VaR figures calculated with the assumption of normal distribution significantly understate the VaR figures computed from the actual historical distribution at high confidence levels. On the other hand, for the same confidence levels, the VaR figures calculated with the assumption of t-distribution are very close to the results found using the actual historical distribution. Finally, in order to speed up the MC simulation technique, which is not commonly preferred in financial applications due to its time consuming algorithm, we implement a parallel version of it.
Estimation of microstretch elastic moduli by the use of vibrational data
(Springer, 2007) Kırış, Ahmet; İnan, Esin
In the present work, a nonlinear wave theory is used for the estimation of the material properties of a "microstretch" medium. For this purpose a thin plate is considered and triplicate Chebyshev polynomial series are used as admissible functions to ensure the satisfaction of geometric boundary conditions of the plate. The Ritz technique is applied to derive the frequency equation of the microstretch plate and an optimization procedure is performed by minimising the least square "distance" between computed natural frequencies from the energy method and measured natural frequencies. To realize the optimization procedure, a genetic algorithm is used to estimate the elastic moduli of microstretch medium.
Development of an indoor navigation system using NFC technology
(IEEE, 2011) Özdenizci Köse, Büşra; Ok, Kerem; Coşkun, Vedat; Aydın, Mehmet Nafiz
Existing indoor navigation systems face with many different technical and usability problems. In this paper we present a Near Field Communication (NFC) based indoor navigation system called NFC Internal in order to eliminate the current indoor navigation problems. NFC Internal enables an easy data transfer for indoor navigation systems just by touching tags spread over a building or a complex. The proposed system has several benefits and has potential to increase the usability of these systems. We discuss the system requirements and explain the phases of NFC Internal through use cases.
Current benefits and future directions of NFC services
(IEEE, 2010) Ok, Kerem; Coşkun, Vedat; Aydın, Mehmet Nafiz; Özdenizci Köse, Büşra
Near Field Communication (NFC), as an emerging and promising technology, is an integration of Radio Frequency Identification (RFID) technology with mobile devices. NFC-enabled mobile devices can act as contactless smart cards and are also capable to read and write data from/to those cards. Research endeavours concerning NFC appear to focus mainly on development of NFC enabled services and applications. On the other hand, benefits and underlying values associated with different NFC applications' service is not yet well elaborated. In this paper we examined existing NFC applications, prototypes and studies from both academia and industry. We analyzed these applications by classifying them into NFC operating modes to surface the nature of underlying value-added services and benefits that they provide. Moreover we emphasized possible future usage scenarios together with directions and questions for future research based on the identified benefits.
Readiness and mindset for IT offshoring: Insights from banking and insurance organizations
(2009-07-13) Aydın, Mehmet Nafiz; de Groot, Jeroen; Van Hillegersberg, Jos
In this research we examine the IT offshore outsourcing (offshoring) practice of a number of leading finance and insurance organizations in the Netherlands. In particular, we investigate the readiness (the state, condition or quality of being ready) and mindset (habits, opinions which affect a person's attitudes) of the organizations for IT offshoring. We examine IT offshoring practice from the process perspective (that is, the dynamics of IT offshoring projects in terms of culture, method use, IT activities, IT governance, knowledge sharing). Among other findings, this research shows that to a greater extent the organizations have realized readiness for method use and mindset for IT activities, and that the overall improvements regarding these aspects have been modest in a two-year period. On the other hand, mindset for dealing with cultural difference has increased while readiness for flexible working, tracking of requirements change, efficient division of work, and systematic communication is still inadequate. Theoretical and practical implications of the findings are further discussed.
NFC loyal: A Beneficial model to promote loyalty on smart cards of mobile devices
(IEEE, 2010) Özdenizci Köse, Büşra; Coşkun, Vedat; Aydın, Mehmet Nafiz; Ok, Kerem
Near Field Communication (NFC) as a new emerging technology currently tries to find a suitable ecosystem. Development of new standards such as secure element, secure channel, as well as Java Card enables creating new ecosystems using a concurrent multi application platform based on Global Platform. We proposed NFC Loyal, which maintains data interaction and data sharing among payment and loyalty applications through our proposed structure, called as Secure Common Domain Management System (SCDM). SCDM as a centralized database management system on the smart card stores valuable iriformation provided by payment applications and shares them with loyalty applications. The direct outcome of using NFC Loyal is the increase in repeat purchases of customers; as well as a business plan among the payment firms, loyalty firms, and the smart card owner. We fully describe the technical including security architectures and background for the SCDM, and explain the details of the proposed model.
Usability of mobile voting with NFC technology
(Acta Press, 2010) Ok, Kerem; Coşkun, Vedat; Aydın, Mehmet Nafiz
Voting is a method to select one opinion or a person often following discussion, debate or an election campaign. After centuries of paper based voting ballots, electronic voting is used along with various technologies. One of the promising technologies is Near Field Communication (NFC) which allows data transfer between NFC-enabled devices and smart tags within a short distance. In this paper, we have presented a new type of a secure voting system, namely NFC voting, and evaluated the system's usability in a university council election with an executable prototype. Among other findings, we found that NFC voting satisfies electronic voting requirements and further increases the subjective usability of the proposed system.
Primitives of service oriented information system development
(2011) Aydın, Mehmet Nafiz; Yalçınkaya, Tayfun
One can find the long standing problems with conceptual modeling such as model transformation, reusability and agility in the classical information system development (ISD). New approaches may help in overcoming these issues in conventional ISD's problems. The service oriented approach which is one of the promising approaches, brings solutions to some existing problems. By adopting service orientation in ISD - which we call service oriented ISD, one can deal with the aforementioned problems. This study examines the very notion of service in the context of conceptual modeling method. In particular, we show how to support service modeling in terms of guidance (that is, the way of modeling). The proposed modeling support is demarcated along with a method at the foundational level. The paper is a conceptual and work-in-progress paper.
Mixed-method validation of pedagogical concepts for an intercultural online learning environment: a case study
(Assoc Computing Machinery, 2007) Law, Effie Lai-Chong; Nguyen-Ngoc, Anh Vu; Kuru, Selahattin
The rise of social software poses the challenges to the design and evaluation of a pedagogically sound online learning environment (OLE). Our OLE addresses these challenges by the integration of three pedagogical concepts - cross-cultural collaboration, self-directed learning and social networking - with the aim to advance participants' competencies and by mixed-method approaches to evaluating the complex situations. A validation trial involving four European countries was conducted. Groups of students co-created a questionnaire, which was assessed to provide an indicator of task performance. Multi-source (surveys, blogs, emails, diaries, chats, videoconference, and interviews) and multi-perspective data (facilitators, students, researchers) were studied with social network analysis, content analysis and conversation analysis. Several a posteriori research questions are addressed.
Automatic XML schema matching
(2009) Kılıç, Yasin Ozan; Aydın, Mehmet Nafiz
As the enterprise systems increasingly use the XML technology in their data presentation, the Enterprise Application Integration is gradually becoming the problem of Xml Schema matching. Different organizations overall need to exchange information which is mainly all in different Xml Schemas and these schemas need to be transformed before an information exchange takes place. Manually transforming different Xml Schemas is a tedious work and this process needs to be done automatically. This is the problem of Automatic Xml Schema Matching. In this paper, an academic literature review will be given on the subject. The article will examine the problems with contemporary solutions while pointing their weaknesses and propose possible solutions to these problems which reduce it to ontological mapping.
Realities & constraints of coal from energy and environmental perspectives
(University of Pittsburgh, 2010) Ekinci, Ekrem
[No abstract available]
Design science in NFC research
(IEEE, 2010) Özdenizci Köse, Büşra; Aydın, Mehmet Nafiz; Coşkun, Vedat; Ok, Kerem
Near Field Communication (NFC), as one of the promising technological developments, provides means to short range contactless communication for mobile phones and other devices alike. NFC has become an attractive design science research area for many academicians due to its exploding growth. A better understanding of the current status of NFC research is necessary to identify the gap between theory and practice. In this paper, we evaluate NFC literature from a design science point of view and seven important guidelines of the design science research are employed for evaluating some of the NFC related studies which propose innovative artifacts. Design science perspective of NFC literature gives beneficial guidelines for future studies. This rigorous and holistic literature review with the objective of bringing to the state-of-art in NFC design science research provides advancement of knowledge in NFC research and further research directions.
Exploring underlying values of NFC applications
(Int Assoc Computer Science & Information Technology Press-Iacsit Press, 2011-08-19) Ok, Kerem; Aydın, Mehmet Nafiz; Coşkun, Vedat; Özdenizci Köse, Büşra
Near Field Communication (NFC) is an integration of contactless smart card communication technology into mobile devices, such as mobile phones. NFC technology provides three operating modes and each mode differs from each other in terms of communication and data processing model. Each mode has distinguishable properties, advantages, and disadvantages; so that each one provides different possible business opportunities and different value-added perspectives. In this paper we survey currently available NFC applications as well as application prototypes. Afterwards, we analyzed those applications in order to find out which benefits they provide.
Getting agile methods to work for cordys global software product development
(Springer-Verlag Berlin, 2011-03-14) Van Hillegersberg, Jos; Ligtenberg, Gerwin; Aydın, Mehmet Nafiz
Getting agile methods to work in global software development is a potentially rewarding but challenging task. Agile methods are relatively young and still maturing. The application to globally distributed projects is in its early stages. Various guidelines on how to apply and sometimes adapt agile methods have been proposed. However, systematic literature reviews reveal that detailed evaluative studies are scarce and limited to small and medium sized projects. This study presents a framework that integrates best practices of adapting and applying agile methods reported in the literature. The framework is applied to analyze the experiences of global software product development company Cordys in a seven year longitudinal case study. Both the framework and the experiences of Cordys documented in this paper will be of value to other larger projects that aim to he successful in applying agile in globally distributed projects.
İki qubit’lik kuantum haberleşme ağlarının eş zamanlılık donanıklık ölçütü ile kuantum Fisher bilgisinin analizi
(IEEE, 2014-06-12) Erol, Volkan; Buğu, Sinan; Özaydın, Fatih; Altıntaş, Azmi Ali
Kuantum dolanıklık, kuantum haberleşme mühendisliğinin en temel kavramlarından biridir. Kuantum sistemlerin dolanıklık ölçütlerine göre sıralanması günümüzde oldukça çok çalışılan konulardan birisidir. İki parçacıklı iki seviyeli sistemlerin (qubit) sıralaması konusu, çok bilinen Eş Zamanlılık (Concurrence), Negatiflik (Negativity) ve Dolanıklığın Göreceli Entropisi (REE) ölçütlerine göre çeşitli araştırmacılar tarafından çalışılmıştır[1-5]. Biz bu çalışmada, iki qubit kuantum sistemlerin sıralamasını Kuantum Fisher Bilgisi ve Eş Zamanlılık dolanıklık ölçütünü karşılaştıracak şekilde analiz etmekteyiz. Çalışma özelinde, bin adet rastgele türetilmiş iki qubit sistemin Eş Zamanlılık değerleri hesaplanmakta; elde ettiğimiz bu sonuçların iki qubit sistemlerde Kuantum Fisher Bilgisi ile karşılaştırılması yapılmakta ve aralarındaki ilginç farklar gözlemlenmektedir.
Kübit-Kütrit kuantum haberleşme sistemleri için negatiflik ve dolanıklığın göreceli entropisi ölçütlerinin analizi
(IEEE, 2015-06-19) Erol, Volkan; Özaydın, Fatih; Altıntaş, Azmi Ali
Kuantum Bilgi Teorisi ve Kuantum Hesaplama konuları geleceğin bilgisayar teknolojisi olarak nitelendirilen ve çok yüksek hızlarda işlem yapacak olması öngörülen Kuantum Bilgisayarlarının teorik temelini oluşturan oldukça sıcak çalışma alanlarıdır. Kuantum Bilgisayarlarında bilginin taşınacağı birim kübit olarak nitelendirilse de, bazı problemler için bu birimlerin üç seviye (trinary) olan kütritlerce kurgulanabileceği teorik olarak gösterilmiştir. Bu çalışma kapsamında, kübit-kütrit Kuantum Haberleşme Sistemlerinin dolanıklıklığını ölçmek için kullanılan Negatiflik ve Dolanıklığın Göreceli Entropisi ölçütlerinin karşılaştırmalı analizi yapılmıştır. Bu bağlamda, rastgele türetilmiş 1000 adet kübit-kütrit sistem durumlarının adı geçen ölçütleri hesaplanmış ve bu değerler sistem durumlarının sıralanması amacıyla karşılaştırılmıştır. Yapılan analiz kapsamında sistem durumlarının sıralaması problemi açısından oldukça ilginç sonuçlar gözlemlenmiştir.

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