Search results for "Service"
showing 10 items of 3964 documents
Channel Occupancy-Based Dynamic Spectrum Leasing in Multichannel CRNs: Strategies and Performance Evaluation
2016
Spectrum leasing has been proposed as an effective approach for enabling more flexible spectrum utilization in CRNs. In CRNs, a primary network (PN) which consists of multiple primary users (PUs) can lease part of the licensed spectrum to secondary users (SUs) in exchange for operational benefits. The focus of this study is to investigate how and to what extent the PN allows spectrum leasing in CRNs, considering the QoS requirements of the PN and the secondary network (SN). Correspondingly, we propose two dynamic spectrum leasing strategies, which can improve the QoS performance of SUs while ensuring sufficient remuneration for PUs. In order to dynamically adjust the portion of leased bandw…
Temporal Fairness Provisioning in Multi-Rate Contention-Based 802.11e WLANs
2005
The IEEE 802.11e extensions for QoS support in WLAN define the transmission opportunity (TXOP) concept, in order to limit the channel holding times of the contending stations in the presence of delay-sensitive traffic. We evaluate the use of TXOP for a different purpose: "temporal fairness" provisioning among stations employing different data rates. We show that the equalization of the channel access times allows each station to obtain its throughput basically (1) proportional to its transmission rate, and (2) independent of the transmitted frame length. This also improves the aggregate throughput of the overall WLAN. For a given TXOP limit, i.e., a granted channel access time, a station is…
A new inter-cloud service-level guarantee protocol applied to space missions
2017
Nowadays, the term cloud computing often falsely assumes the availability of an unlimited pool of resources. On the contrary, if a cloud provider reaches its limits, it may pose the risk of breaking their service level agreement (SLA). Space agencies could start using the cloud computing model within their IT infrastructure with multiple ground control points around the world to reduce the cost. An inter-cloud communication protocol with a guarantee of the service level will significantly reduce the cost if each ground control segment is considered as a cloud provider. This paper outlines a new protocol that was developed to take into consideration the end-to-end service-level guarantee. Th…
Methods for Modeling Ecosystem Services: A Review
2015
Abstract Modeling ecosystem services (ES) is an essential tool for the development of strategies that will ensure their future supply, provision and quantification. Given the rapid development in this area of research, a review of the different approaches used to model ES was performed, using an analytical framework based on five criteria for comparing the existing methodological approaches: the types of ES, availability of data sources, spatial scale, types of models used and the possible outcomes of the models. Regulating services were the most commonly modeled, followed by provisioning, cultural, and supporting services. The most frequently used data for modeling were secondary data (alr…
Semantic Web Services for Smart Devices Based on Mobile Agents
2005
Among traditional users of Web resources, industry has a growing set of smart industrial devices with embedded intelligence. Just like humans, they need online services (i.e., for condition monitoring, remote diagnostics, maintenance, etc.). In this paper, we present one possible implementation framework for such Web services. Such services should be Semantic Web enabled and form a Service Network based on internal and external agents’ platforms, which can host heterogeneous mobile agents and coordinate them to perform needed tasks. The concept of a “mobile service component†assumes not only exchanging queries and service responses, but also delivering and composition of a service pro…
Personalized distance learning based on multiagent ontological system
2004
The paper presents architecture of a personalized distance learning system based on multiagent technology and ontological modelling of students' profiles. Delocalization of a student data in the system is achieved by software agents, which assumed to be distributed at different platforms. These platforms operate as separate Web services and use the ACL (agent communication language) for the data transfer. In this paper the algorithm is proposed, according to which the multiagent ontological system for personalized distance learning (MOSPDL) solves the tasks of distant learning process automation, which assume utilization of the ontological models of students' and learning resources' profile…
Location-Aware Mobile Intrusion Detection with Enhanced Privacy in a 5G Context
2010
Published version of an article from the journal: Wireless Personal Communications. The original publication is available at Spingerlink. http://dx.doi.org/10.1007/s11277-010-0069-6 The paper proposes a location-aware mobile Intrusion Prevention System (mIPS) architecture with enhanced privacy that is integrated in Managed Security Service (MSS). The solution is envisaged in a future fifth generation telecommunications (5G) context with increased but varying bandwidth, a virtualised execution environment and infrastructure that allows threads, processes, virtual machines and storage to be migrated to cloud computing services on demand, to dynamically scale performance and save power. 5G mob…
Mobile Electronic Commerce: Emerging Issues
2000
There are many definitions for Mobile Electronic Commerce (M-Commerce). We define M-Commerce as any type of transaction of an economic value having at least at one end a mobile terminal and thus using the mobile telecommunications network. The Wireless Application Protocol (WAP) plays an important role in m-commerce by optimizing Internet standards for the constraints of the wireless environment and thus bridging the gap between Internet and mobile world. Mobile Network Operators can play a major role in m-commerce by being strategically positioned between customers and content/service providers. In this paper we investigate the roles the operator can play in m-commerce and discuss respecti…
Auxilum Medicine: A Cloud Based Platform for Real-Time Monitoring Medical Devices
2015
Nowadays, time is a very valuable resource and can make the difference between life and death. Having knowledge about this fact we decided to deal with one of the most important aspects of contemporary medicine, EMS (emergency medical services) response time. Modern systems that encourage intelligent communication methods between medical devices and doctors are a must in ubiquitous health care environments. Auxilum Medicine fosters a triple-win situation regarding the relationship between medical institutions, doctors and patients. Emergency patients should be treated with utmost care because their life is hanging by a thread if nobody is present to take immediate action. We are presenting …
ITIL Implementation: The Role of ITIL Software and Project Quality
2012
This research will investigate the implementation status of the Information Technology Infrastructure Library (ITIL) reference processes and the influence of ITIL software quality and ITIL project quality on implementation status. The paper analyzes data from a survey of 160 Nordic companies.