Yönetim Bilişim Sistemleri Bölümü Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12469/68

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Management Information Systems: the Virtual Team Scorecard (vts)
(2013) Oberer, Birgit; Erkollar, Alptekin
Organizations resisting changes are missing opportunities to grow or to become or remain competitive. Management Information Systems (MIS) used as decision support systems may support organizations in making use of changes in environmental conditions. Nevertheless innovative structures are needed to motivate organizations contributing in change projects. Tn this study a virtual team scorecard which can be used as a management information system enabling requirements analyses for managing virtual teams in organizations and in virtual teams with members of different organizations was developed in two different versions: (a) an intemal VTS and (b) an inter-organizational VTS. The results revealed that the developed virtual team scorecard covers all the main strategic factors from a management perspective and in particular relies on the qualitative factors of the team determines the quality and group dynamics deficits of a team and may provide clues for knowing which factors should receive special attention. Furthermore the developed scorecard can be used for inter-organizational teams and any kind of structured co-operation between organizations.
On the Selection of Interpolation Points for Rational Krylov Methods
(Springer-Verlag Berlin, 2012) Yetkin, E. Fatih; Dağ, Hasan
We suggest a simple and an efficient way of selecting a suitable set of interpolation points for the well-known rational Krylov based model order reduction techniques. To do this some sampling points from the frequency response of the transfer function are taken. These points correspond to the places where the sign of the numerical derivation of transfer function changes. The suggested method requires a set of linear system's solutions several times. But they can be computed concurrently by different processors in a parallel computing environment. Serial performance of the method is compared to the well-known H-2 optimal method for several benchmark examples. The method achieves acceptable accuracies (the same order of magnitude) compared to that of H-2 optimal methods and has a better performance than the common selection procedures such as linearly distributed points.
Citation - WoS: 11
Mobile Learning in Higher Education: a Marketing Course Design Project in Austria
(Elsevier Science Bv, 2013) Oberer, Birgit; Erkollar, Alptekin
The course concept introduced in this paper was implemented in 2011 in a university in Austria and shows an approach for integrating mobile learning modules in higher education. The results of the course as revealed in the research show the advantages as well as the potential for improvement of the system and its use in higher education. (C) 2013 The Authors. Published by Elsevier Ltd.
Graph Optimized Locality Preserving Projection Via Heuristic Optimization Algorithms
(IEEE, 2019) Ceylan, Oğuzhan; Taşkın, Gülşen
Dimensionality reduction has been an active research topic in hyperspectral image analysis due to complexity and non-linearity of the hundreds of the spectral bands. Locality preserving projection (LPP) is a linear extension of the manifold learning and has been very effective in dimensionality reduction compared to linear methods. However, its performance heavily depends on construction of the graph affinity matrix, which has two parameters need to be optimized: k-nearest neighbor parameter and heat kernel parameter. These two parameters might be optimally chosen simply based on a grid search when using only one representative kernel parameter for all the features, but this solution is not feasible when considering a generalized heat kernel in construction the affinity matrix. In this paper, we propose to use heuristic methods, including harmony search (HS) and particle swarm optimization (PSO), in exploring the effects of the heat kernel parameters on embedding quality in terms of classification accuracy. The preliminary results obtained with the experiments on the hyperspectral images showed that HS performs better than PSO, and the heat kernel with multiple parameters achieves better performance than the isotropic kernel with single parameter.
Citation - WoS: 22
Citation - Scopus: 34
Grey Wolf Optimizer for Allocation and Sizing of Distributed Renewable Generation
(Institute of Electrical and Electronics Engineers Inc., 2019) Ahmadi, Bahman; Ceylan, Oğuzhan; Özdemir, Aydoğan
Increasing penetration of distributed energy resources (DERs) have brought operational and control philosophy changes in Smart Grids (SGs). Renewable energy based technologies are becoming more important due to their economic and environmental impacts. Distributed generations (DGs) in the form of small renewable energy resources such as solar photovoltaics (PVs) and Wind Turbines (WTs) are connected in radial distribution networks near to the loads. This paper presents optimal siting and sizing of distributed renewable energy resource to maintain voltage magnitude profiles. Bus voltage magnitude differences for each hour in a day of a distribution system are formulated as an objective function. Three consecutive days are taken into account representing the three seasons of a year. A new nature inspired algorithm Grey Wolf Optimizer (GWO) is used as a solution tool. The proposed formulation is applied to 33 bus and 69 bus radial distribution networks. MATLAB simulations are performed to validate the performance of the approach. Simulation results are discussed and compared with of the several available ones'.
Citation - Scopus: 27
Land Use and Land Cover Classification of Sentinel 2-A: St Petersburg Case Study
(International Society for Photogrammetry and Remote Sensing, 2019) Çavur, Mahmut; Düzgün, Hafize Şebnem; Kemeç, Serkan; Demirkan, Doğa Çağdaş
Land use and land cover (LULC) maps in many areas have been used by companies, government offices, municipalities, and ministries. Accurate classification for LULC using remotely sensed data requires State of Art classification methods. The SNAP free software and ArcGIS Desktop were used for analysis and report. In this study, the optical Sentinel-2 images were used. In order to analyze the data, an object-oriented method was applied: Supported Vector Machines (SVM). An accuracy assessment is also applied to the classified results based on the ground truth points or known reference pixels. The overall classification accuracy of 83,64% with the kappa value of 0.802 was achieved using SVM. The study indicated that of SVM algorithms, the proposed framework on Sentinel-2 imagery results is satisfactory for LULC maps.
Citation - WoS: 1
Electronic Government Services in Europe: Strategies Projects and Applications
(Academic Journals, 2011) Oberer, Birgit; Erkollar, Alptekin
In Europe national electronic government incentives have made a significant contribution to the modernization of administration and its processes as well as its customer oriented services. In this study European strategies and projects for electronic government as well as their implementation plans were analyzed followed by an examination of the electronic services offered by the national governmental authorities in Austria European pioneers in electronic government the United Kingdom the electronic government leader in Europe 2010 and Spain as a Southern European electronic government representative. The results revealed that Europe has developed hybrid electronic government strategies for the whole community and has launched projects in that field in which member countries have to participate in order to offer electronic government services at a high level and in a competitive international environment. On a whole offering a single gateway to governmental information and transactions generally offers higher attractiveness for conducting nationwide business and all incentives for electronic government focus on developing good practices in the area of efficient and effective electronic government. Nevertheless strategies are transformed and implemented in different ways and the intensity in the member countries and a union-wide electronic government is still in its infancy.
Citation - WoS: 1
Using Random Forest Tree Classification for Evaluating Vertical Cross-Sections in Epoxy Blocks To Get Unbiased Estimates for 3d Mineral Map
(Gazi University, 2021) Camalan, Mahmut; Çavur, Mahmut
Areal mineral maps are constructed from the polished sections of particles that settle to the bottom of epoxy resin. However, heavy minerals can preferentially settle to the bottom, making the polished surface rich in heavy minerals. Therefore, polished sections will become biased estimates of the volumetric (3D) map. The study aims to test whether any vertical cross-section (any section along the settling direction of particles) can be an unbiased estimate of the 3D mineral map of a chromite ore sample. For the purpose of this study, 2D maps of the vertical cross-sections were acquired by using Random Forest classification coupled with image pre- and post-processing tools. Then, 3D mineral maps were converted from 2D maps without assuming stereological errors. The modal mineralogy and particle size distributions predicted from 3D maps were compared with the same features estimated from the particulate sample by XRD and dry sieving analyses, respectively. Any 2D map which yields a modal mineralogy and a size distribution similar to the true analyses was selected as an unbiased estimate of the true 3D map. The results suggest that any vertical cross-section is an unbiased estimate, unlike polished section at which heavier minerals settle preferentially.
Citation - Scopus: 1
Metadata Action Network Model for Cloud Based Development Environment
(Springer, 2020) Aydın, Mehmet Nafiz; Perdahçı, Ziya Nazım; Şafak, İlker; van Hillegersberg, Jos
Cloud-based software development solutions (entitled as Platform-as-a-Service, Low-Code platforms) have been promoted as a game changing paradigm backed by model-driven architecture and supported by various cloud-based services. With the engagement of a sheer number of platform users (experienced, novel, or citizen developers) these platforms generate invaluable data and that can be considered as user metadata actions. As cloud-based development solutions provide novice users with a new development experience (performing data actions that altogether leads to a successful software app), users often times face with uncertainty about development performance; how good or complete is app development? Thus, the issue addressed in this research is how to measure user performance by using digital trace data generated on the cloud platform from a Network Science perspective. This research proposes a novel approach to leveraging digital trace data on Platform-as-a-Service (PaaS) from a Network Science perspective. The proposed approach considers the importance of digital trace data as metadata actions on PaaS and introduces a network model (so-called Metadata Action Network), which is claimed to be the result of reconstruction of events of developer’s actions. We show suitability of the proposed approach to better understanding of real-world digital trace data on PaaS solution and elaborate basic performance analytics on a PaaS solution with research and practical implications.
Citation - Scopus: 1
National Electronic Government Strategies in Austria
(ACAD Conferences Ltd, 2011) Oberer, Birgit; Erkollar, Alptekin
One of the most emerging concepts of information technology is the one of electronic government. Electronic services that are made available by governments to citizens businesses and other governments (international) or governmental authorities (national) are general proof of the changes being made in the public sector. Intersecting the government citizen and business domain a business model can be defined considering the government-to-business government-to-citizen and government-to-government approaches. Governments around the world try to follow their most of the time ambitious strategies to become or stay competitive. In this study Austrian strategies and projects for electronic government as well as their implementation plans were analysed followed by an examination of the electronic services offered by the national governmental authorities in Austria one pioneer in electronic government in Europe leading in the European E-Government ranking 2010 and the declared 'European champion in eGovernment' for the fourth time in a row. The results revealed that Austria has developed hybrid electronic government strategies and has launched projects in that field in which national governmental authorities have to participate in order to offer electronic government services at a high level and in a competitive international environment. On a whole offering a one-stop shop gateway to governmental information and transactions generally offers higher attractiveness for conducting nationwide business and all incentives for electronic government focus on developing good practices in the area of efficient and effective electronic government. Nevertheless national strategies are transformed and implemented in different ways not always following the one-stop-shop approach and contributing to the development of isolated applications instead of integrated ones.
Parallel Implementation Of Iterative Rational Krylov Methods For Model Order Reduction
(IEEE, 2010) Yetkin, E. Fatih; Dağ, Hasan
Model order reduction (MOR) techniques are getting more important in large scale computational tasks like large scale electronic circuit simulations. In this paper we present some experimental work on multiprocessor systems for rational Krylov methods. These methods require huge memory and computational power especially in large scale simulations. Therefore these methods are fairly suitable for parallel computing.
Analysis and Implications of the Giant Component for an Online Interactive Platform
(Int Business Information Management Assoc-IBIMA, 2016) Aydın, Mehmet Nafiz; Perdahci, N. Ziya
This research is concerned with practical and research challenges related to understanding the nature of online interactive platforms. So-called network science is adopted to investigate the very nature of these systems as complex systems. In this regard we examine an online interactive health network and show that the interactive platform examined exhibits essential structural properties that characterize most real complex networks. We basically look into the largest connected component so-called a giant component (GC) to better understand how the representative network has established. In particular we apply dynamic network analysis to investigate how the GC has evolved over time. We identify a particular pattern towards emerging a GC. Implications of the patterns have been elaborated from a management perspective. We recommend that the basic stages of the emergence of the GC might be of interest to platform managers while evaluating performance of online platforms.
Citation - Scopus: 1
Multi-Agent Model of Electricity Networks - a Perspective on Distribution Network Charges
(Institute of Electrical and Electronics Engineers Inc., 2019) Pisica, Ioana; Ceylan, Oğuzhan
In the UK, DNOs are regulated by Ofgem to use two common distribution use of system charging methodologies: Common Distribution Charging Methodology and Extra-High Voltage Distribution Charging Methodology. To account for the changing landscape of the energy sector, Ofgem has recently published a consultation paper on changes to DUoS charging structure. This paper looks into the implications of distribution network charging in consumer-level adoption of low carbon technologies and vice-versa, using an agent-based model approach.
Citation - WoS: 3
Sustainable Knowledge Management Shown in the Example of a Company Operating on the Telecommunications Market
(Elsevier Science Bv, 2015) Oberer, Birgit; Erkollar, Alptekin
Modern organizations are being strongly pressured to increase agility and competitiveness operate on the global market and engage in alliances. One key success factor for these organizations is the human factor. Human resource and knowledge managers line managers and team leaders are ultimately responsible for the effective and efficient operation of the organization. They are collectively responsible for the evolution of the organization in order to meet new challenges. These responsibilities can only be born if the these managers have the appropriate knowledge in their respective fields of expertise and know how to share this knowledge sustainable among each other and have an effective awareness of the need for a knowledge sharing network within the organization. In this study we develop a social media based knowledge management system for a company which operates in the telecommunications market serving a special niche market. Managers from similar disciplines contribute to the project in sharing their knowledge on social media mainly Google Plus. We develop structures for a sustainable knowledge management environment for companies in the example of managers all of who have expertise in management or information technology. Applying social media for managing knowledge could turn these managers into knowledge leaders in their organizations. The results of the forthcoming analysis will show the advantages and potential for improvement for using social media knowledge bases for knowledge exchange. (C) 2015 The Authors. Published by Elsevier B.V.
Citation - Scopus: 6
Parallel-In Implementation of Transient Stability Analysis on a Linux Cluster With Infiniband
(IEEE, 2012) Soykan, Gürkan; Flueck, Alexander J.; Dağ, Hasan
On-line transient stability analysis is an inevitable way to provide real time power system security and control. Parallel computing is one of the most viable ways to perform on-line transient stability analysis. This paper presents the performance results of a parallel-in-space algorithm based on a multilevel partitioning scheme on an Infiniband cluster system. The algorithm decreases the transient stability simulation time using METIS for partitioning in conjunction with the linearized update solution process of the Very Dishonest Newton Method when solving the differential-algebraic systems of equations [1]. Two real power systems a 3493-bus system with 844 generators and a 7935-bus system with 2135 generators are tested on a Linux-cluster system with 16 nodes. Each node has 2 multicore processors and is connected to each other by Infiniband network. The properties of a test system have a large impact on the performance of the parallel algorithm used since it affects communication duration. © 2012 IEEE.
Citation - Scopus: 47
Random Capsnet Forest Model for Imbalanced Malware Type Classification Task
(Elsevier, 2021) Çayır, Aykut; Ünal, Uğur; Dağ, Hasan
Behavior of malware varies depending the malware types, which affects the strategies of the system protection software. Many malware classification models, empowered by machine and/or deep learning, achieve superior accuracies for predicting malware types. Machine learning-based models need to do heavy feature engineering work, which affects the performance of the models greatly. On the other hand, deep learning-based models require less effort in feature engineering when compared to that of the machine learning-based models. However, traditional deep learning architectures components, such as max and average pooling, cause architecture to be more complex and the models to be more sensitive to data. The capsule network architectures, on the other hand, reduce the aforementioned complexities by eliminating the pooling components. Additionally, capsule network architectures based models are less sensitive to data, unlike the classical convolutional neural network architectures. This paper proposes an ensemble capsule network model based on the bootstrap aggregating technique. The proposed method is tested on two widely used, highly imbalanced datasets (Malimg and BIG2015), for which the-state-of-the-art results are well-known and can be used for comparison purposes. The proposed model achieves the highest F-Score, which is 0.9820, for the BIG2015 dataset and F-Score, which is 0.9661, for the Malimg dataset. Our model also reaches the-state-of-the-art, using 99.7% lower the number of trainable parameters than the best model in the literature.
Citation - Scopus: 11
Exploring Competitive Intelligence Practices of French Local Public Agricultural Organisations
(Halmstad University, 2014) Bisson, Christophe
Modern agriculture has increased the need for information when making strategic decisions for farmers since they must be more entrepreneurial to survive. This paper investigates the levels of Competitive Intelligence practices in a French Regional Chamber of Agriculture and its four Departmental Chambers of Agriculture to examine the ability of these public organisations to keep fulfilling one of their missions which is to provide the necessary information and knowledge to farmers. Thus this study proposes a behavioural and operational typology of Competitive Intelligence practice. Both types of organisations demonstrate that they are not well adapted to support the entrepreneurial farmers on this issue. The findings of this study and the diagnosis of the Competitive Intelligence practices applied to the typology could be of help to increase their and other public agricultural structures performance levels. Furthermore the platform has the potential to inspire the public sector through subsequent adaptations.
Citation - WoS: 3
Citation - Scopus: 1
A Critical Analysis of Current Legal Developments on the Political Participation of Minorities in Turkey
(2010) Akbulut, Olgun
This is a follow-up article to the one published in the IJMGR half a decade ago (Vol. 12 2005). Although there have been domestic and international legal cases that are directly concerned with the political participation of minorities in Turkey few improvements have been made in law covering the subject. This encouraged this author to analyse and criticise the judgements of the European Court of Human Rights and the legal and political actors at domestic level. The aim of this article is to reflect upon how international human rights monitoring affects national laws in certain thorny issues such as the rights of minorities. Since the current and previous articles have a common theme and complement each other I strongly recommend reading both articles. © 2010 Martinus Nijhoff Publishers.
Citation - WoS: 1
Citation - Scopus: 3
When Sharing Less Means More: How Gender Moderates the Impact of Quantity of Information Shared in a Social Network Profile on Profile Viewers' Intentions About Socialization
(Routledge, 2014) Baruh, Lemi; Chisik, Yoram; Bisson, Christophe; Şenova, Başak
This study summarizes the results from a 2 (low vs. high information) × 2 (female vs. male profile) experiment that investigates the impact of quantity of information shared on a Social Network Site (SNS) profile on viewers' intentions to pursue further interactions with the profile owner. Quantity of information had no statistically significant effect on intentions to further socialize online. The two-way interaction between information quantity and profile gender was such that for male profiles more information increased profile viewers' intentions to further socialize with the profile owner whereas for female profiles the opposite was the case. The three-way interactions among quantity of information profile gender and profile viewer's gender underline a tendency for male profile viewers to respond more positively to higher information shared by profiles from their own gender. For female viewers this effect although in the same direction was smaller. © 2014 Copyright Eastern Communication Association.
Citation - WoS: 2
A Country-Specific Analysis on Internet Interconnection Ecosystems
(IEEE, 2017) Çakmak, Görkem; Aydın, Mehmet Nafiz
With the proliferating number of diverse participants and destinations to reach, the Internet construct has become more intricate to assay. Today, Internet Service Providers (ISPs) establish resilient networks from multiple providers and broaden the number of peering links - as financially as viable. However, the complex structure of the global Internet ecosystem and entwined roles of Internet players simply prevent us from conducting generalized models for grasping interconnections which could be applied globally regardless of the local surroundings. In this paper, the global inter-domain Internet topology is scrutinized by the help of interconnection characteristics within a country-specific stance. Our study on the Internet ecosystems helps us highlight the non-uniformity of interconnections by using both "real world" metrics and network science metrics. One of the significant findings that the analysis yields is that presence of well-established Internet Exchange Points (IXPs) in an interconnection ecosystem - besides the benefit of bolstering the peering fabric - increases the competitive nature of Internet transit market and boosts the inclination to multi-home for stub networks, thus increases the resilience of national Internet constructs.

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