Search results for "Computer network"
showing 10 items of 1634 documents
AN ATTEMPT TO INVESTIGATE THE IMPACT OF SELECTED INFRASTRUCTURE INVESTMENTS ON THE POTENTIAL DEVELOPMENT OF THE BIGGEST EUROPEAN CITIES. APPLICATION …
2019
Przedmiotem niniejszego artykułu jest symulacyjne badanie dyfuzji zmian gospodarczych, oparte na ugruntowanym modelu pośrednich możliwości. Użyty algorytm umożliwił detekcję makroregionów europejskich, w których istnieje wyraźnie podwyższony potencjał rozwoju wielobranżowych klastrów gospodarczych. Eksperymenty symulacyjne wykonano w dwóch seriach: dla prognozy wpływu działania Centralnego Portu Komunikacyjnego oraz dla działania CPK łącznie z budowaną jednocześnie Via Carpatia (czyli tzw. “Nowym Szlakiem Bursztynowym”). W niniejszym artykule staraliśmy się odpowiedzieć na pytanie: które rejony Europy najwięcej zyskają działaniu Centralnego Portu Komunikacyjnego?
 Osiągni…
Dependability-Based Reliability Analysis in URC Networks: Availability in the Space Domain
2019
Ultra-reliable low latency communication (URLLC), which refers to achieving almost 100% reliability at a certain (satisfactory) level of services and stringent latency, is one of the key requirements for 5G networks. However, most prior studies on reliable communication did not address space domain analysis. Neither were they pursued from a dependability perspective. This paper addresses the ultra-reliable communication (URC) aspect of URLLC and aims at advocating the concept of URC from a dependability perspective in the space domain. We perform in-depth analysis on URC considering both the spatial characteristics of cell deployment and user distributions, as well as service requirements. …
System Times and Channel Availability for Secondary Transmissions in CRNs: A Dependability Theory based Analysis
2017
[EN] Reliability is of fundamental importance for the performance of secondary networks in cognitive radio networks (CRNs). To date, most studies have focused on predicting reliability parameters based on prior statistics of traffic patterns from user behavior. In this paper, we define a few reliability metrics for channel access in multichannel CRNs that are analogous to the concepts of reliability and availability in classical dependability theory. Continuous-time Markov chains are employed to model channel available and unavailable time intervals based on channel occupancy status. The impact on user access opportunities based on channel availability is investigated by analyzing the stead…
Per-user availability for ultra-reliable communication in 5G: Concept and analysis
2018
Emerging 5G mobile networks envisage ultra-reliable communication (URC) as one of the major requirements for anytime anywhere communication. Although URC has recently attracted a lot of attention in the research community, existing work seems to rely on approaching reliability merely from a time domain perspective. However, both time and space domain parameters affect reliability and need to be investigated. This paper introduces a dependability theory based definition for per-user availability targeted at 5G networks. The advocated definition promotes both space and time domain components for URC provisioning. Furthermore, we perform reliability and availability analysis and simulations co…
On Distinguishing between Reliable and Unreliable Sensors Without a Knowledge of the Ground Truth
2015
In many applications, data from different sensors are aggregated in order to obtain more reliable information about the process that the sensors are monitoring. However, the quality of the aggregated information is intricately dependent on the reliability of the individual sensors. In fact, unreliable sensors will tend to report erroneous values of the ground truth, and thus degrade the quality of the fused information. Finding strategies to identify unreliable sensors can assist in having a counter-effect on their respective detrimental influences on the fusion process, and this has has been a focal concern in the literature. The purpose of this paper is to propose a solution to an extreme…
A Joint Time-Space Domain Analysis for Ultra-Reliable Communication in 5G Networks
2018
Reliable communication is a fundamental service level agreement criterion in wireless networks. Moreover, it is a performance indicator for ultra- reliable communication (URC) in emerging 5G networks. In URC, the quality of the delivered services to end-users ultimately depends on the availability of network resources as well as the quality of the received signal. Therefore, in order to analyze URC in cellular networks, both time- dependent spectrum availability and space-dependent service quality need to be considered. In this paper, we present a combined time and space domain analysis on network reliability based on a continuous time Markov chain model. To this end, we introduce a new rel…
Achieving Ultra Reliable Communication in 5G Networks: A Dependability Perspective Availability Analysis in the Space Domain
2017
As part of the 5G communication paradigm, ultra reliable communication (URC) is envisaged as an important technology pillar for providing anywhere and anytime services to end users. While most existing studies on reliable communication do not investigate this problem from a dependability theory perspective, those dependability-based studies tend to define reliability merely in the time domain. In this letter, we advocate extending the concept of URC from the dependability perspective also in the space domain . We initiate definitions on cell availability and system availability. The availability and the probability of providing a guaranteed level of availability in a network are analyzed bo…
Restrictions on data-driven political micro-targeting in Germany
2017
The revitalisation of canvassing in recent elections is strongly related to campaigns´ growing possibilities for analysing voter data to gain knowledge about their constituents, identifying their most likely voters and serving up personalised messages through individual conversations. The research literature about political micro-targeting hardly ever focusses on campaigns in parliamentary democracies with strict data protection laws. Based on in-depth expert interviews we introduce a framework of constraints in strategic political communication and reveal several restrictions on the macro, meso and micro levels which hinder the implementation of sophisticated data strategies in Germany. We…
Online Black-Markets: An Investigation of a Digital Infrastructure in the Dark
2021
AbstractThis paper investigates the functioning of Online Black-Markets (OBMs), i.e. a digital infrastructure operating in the Dark Net that enables the exchange of illegal goods such as drugs, weapons and fake digital identities. OBMs exist notwithstanding adverse conditions such as police interventions, scams and market breakdowns. Relying on a longitudinal case study, we focus on the dynamics of interactions among actors and marketplace technologies and we identify three mechanisms explaining OBMs operations. In particular, we show that OBMs infrastructure is the result of commoditization, platformization and resilience processes. Our contribution relies on the identification of communit…
Online pricing for demand-side management in a low-voltage resistive micro-grid via a Stackelberg game with incentive strategies
2022
It has been demonstrated that online pricing mechanisms are a viable solution for demand side management in power systems. This study deals with the analysis and design of a droop-controlled low-voltage resistive AC micro-grid network system. Such a system is subjected to a dynamic demand obtained from an online pricing mechanism, which is proposed as a novelty in the study of micro-grids. This mechanism is derived from a variation of the Stackelberg game, which includes the use of incentive strategies. First, a configuration in which a supplier announces an incentive function and (Formula presented.) -consumers’ reaction to the resulting personalised price is presented. Then, a detailed st…