Search results for " Communication"
showing 10 items of 4937 documents
An efficient cluster-based outdoor user positioning using LTE and WLAN signal strengths
2015
In this paper we propose a novel cluster-based RF fingerprinting method for outdoor user-equipment (UE) positioning using both LTE and WLAN signals. It uses a simple cost effective agglomerative hierarchical clustering with Davies-Bouldin criterion to select the optimal cluster number. The positioning method does not require training signature formation prior to UE position estimation phase. It is capable of reducing the search space for clustering operation by using LTE cell-ID searching criteria. This enables the method to estimate UE positioning in short time with less computational expense. To validate the cluster-based positioning real-time field measurements were collected using readi…
Domain Specific Case Tool for ICT-Enabled Service Design
2014
One major problem in service design is the limited availability of information gathered during the development process. In particular, information on end-user requirements is difficult for designers, developers, and maintainers to access. Here, we provide a mechanism that supports the gathering and modeling of various types of information throughout the service and software development life cycle. As various existing tools focus on a particular part of the life cycle, essential information is not available, or it is more difficult to obtain in later stages. The linkage between information collected in the different stages is often lost. The implemented tool support enables the modeling of r…
Online anomaly detection using dimensionality reduction techniques for HTTP log analysis
2015
Modern web services face an increasing number of new threats. Logs are collected from almost all web servers, and for this reason analyzing them is beneficial when trying to prevent intrusions. Intrusive behavior often differs from the normal web traffic. This paper proposes a framework to find abnormal behavior from these logs. We compare random projection, principal component analysis and diffusion map for anomaly detection. In addition, the framework has online capabilities. The first two methods have intuitive extensions while diffusion map uses the Nyström extension. This fast out-of-sample extension enables real-time analysis of web server traffic. The framework is demonstrated using …
An Approach for Network Outage Detection from Drive-Testing Databases
2012
A data-mining framework for analyzing a cellular network drive testing database is described in this paper. The presented method is designed to detect sleeping base stations, network outage, and change of the dominance areas in a cognitive and self-organizing manner. The essence of the method is to find similarities between periodical network measurements and previously known outage data. For this purpose, diffusion maps dimensionality reduction and nearest neighbor data classification methods are utilized. The method is cognitive because it requires training data for the outage detection. In addition, the method is autonomous because it uses minimization of drive testing (MDT) functionalit…
Context-aware data caching for 5G heterogeneous small cells networks
2016
In this work, we investigate the problem of context-aware data caching in the heterogeneous small cell networks (HSCNs) to provide satisfactory to the end-users in reducing the service latency. In particular, we explore the storage capability of base stations (BSs) in HSCNs and propose a data caching model consists of edge caching elements (CAEs), small cell base stations (SBSs), and macro cell BS (MBS). Then, we concentrate on how to efficiently match the data contents to the different cache entities in order to minimize the overall system service latency. We model it as a distributed college admission (CA) stable matching problem and tackle this issue by utilizing contextual information t…
Semantic Portal as a Tool for Structural Reform of the Ukrainian Educational System
2014
Education is recognized as a fundamental enabler of human development. The adoption of information and communications technologies (ICTs) by education (especially in developing countries) contributes to educational system reforms, in addition to the traditional advantages, such as social openness and accessibility. Yet the academic community has not studied sufficiently the challenging context in which ICTs are used as instruments for the reform of inefficient, and sometimes even corrupted, educational systems rather than just as means for smarter classrooms, remote access, or content management. The object of this study is Ukrainian higher education (HE) and its quality assurance (QA) syst…
Cross-Cultural Factors in Experiencing Online Video Contents in Product Marketing
2017
Although online shops represent convenient tools to buy and sell products, they do not offer as rich multisensory experiences than physical retailing offers. Audio-visual contents could provide dynamic multisensory information and offer more engaging experiences. However, to be successful, audio-visual contents need to be adjusted to the cultural characteristics of the users. This manuscript presents a study in which Spanish and Finnish participants interacted with audiovisual products depicting videos of the brand design. Through content analysis of participants' verbalizations, the authors identified categories and subcategories that defined the representation of the video elements and th…
Identity Use and Misuse of Public Persona on Twitter
2016
Social media sites have appeared during the last 10 years and their use has exploded all over the world. Twitter is a microblogging service that has currently 320 million user profiles and over 100 million daily active users. Many celebrities and leading politicians have a verified profile on Twitter, including Justin Bieber, president Obama, and the Pope. In this paper we investigate the '‘hundreds of Putins and Obamas phenomenon’ on Twitter. We collected two data sets in 2015 containing 582 and 6477 profiles that are related to the G20 leaders’ profiles on Twitter. The number of namesakes varied from 5 to 1000 per leader. We analysed in detail various aspects of the Putin and Erdogan rela…
Does the Learning Channel Really Matter? - Insights from Commercial Online ICT-training
2017
Evolving ICT has provided new options to participate to training. Online participation has been found to be cost effective, helping people to deal with the time and cost pressures they are facing on their jobs. Previous studies conducted in higher education sector indicates that student satisfaction or learning outcomes does not differ between online and classroom participants. However, little is known what is the situation in commercial ICT-training. This paper studied course feedbacks from courses having both online and classroom participants of a commercial ICT-training provider. Results revealed that the learning channel has no effect on satisfaction, perceived teacher’s substance and t…
Operator Revenue Analysis for Device-to-Device Communications Overlaying Cellular Network
2018
Device-to-device (D2D) communications has recently gathered significant research interest due to its efficient utilization of already depleting wireless spectrum. In this article, we considered a scenario where D2D users communicate in the presence of cellular users in an overlay network setup. In order to analyze the revenue of service providers in monetary terms, the paper provides exact expressions of operator profit for both D2D and cellular users. More specifically, we take into account different network parameters including user density, transmit power and channel variations to understand their impact on the total revenue of the operator. Finally, we derive the balancing value of freq…