Search results for "Computer network"
showing 10 items of 1634 documents
Combining Social Service and Healthcare as the First Country in the World : Exploring the Impacts on Information Systems
2018
The Finnish government has decided to implement a reform in the social and healthcare system by combining the two in the future. There are several drivers for this change that have been identified. Large number of information systems that are not interoperable, challenges in data management and isolated service offering are the most significant ones. In the government’s strategy for the future the digitalisation will provide tools to solve these challenges. In this paper the landscape is outlined and the architecture choices are discussed. The enterprise architecture is applied for the largest county comprising of over 1900 social service and healthcare related information systems. The targ…
Fuzzy sliding mode control design for a class of disturbed systems
2014
This paper discusses the problem of the fuzzy sliding mode control for a class of disturbed systems. First, a fuzzy auxiliary controller is constructed based on a feedback signal not only to estimate the unknown control term, but also participates in the sliding mode control due to the fuzzy rule employed. Then, we extend our theory into the cases, where some kind of system information can not be obtained, for better use of our theoretical results in real engineering. Finally, some typical numerical examples are included to demonstrate the effectiveness and advantage of the designed sliding mode controller. Refereed/Peer-reviewed
Moving RTS/CTS to the frequency domain: an efficient contention scheme for 802.11ax networks
2019
In this paper, we propose a contention mechanism based on the execution of multiple contention rounds in the frequency domain (ReCHo), which is designed to offer high throughput performance and robustness with respect to imperfect carrier sensing. The main idea is using narrow tones as signalling messages for performing channel access contentions and allowing the Access Point (AP) to echo these signals, in order to extend the sensing capabilities to all the stations associated to the AP. In particular, we refer to the emerging IEEE 802.11ax standard, showing how our scheme can boost performance of random access with respect to the current version of IEEE 802.11ax OFDMA Back-Off (OBO), even …
'Good to Repeat': Making Random Access Near-Optimal with Repeated Contentions
2020
Recent advances on WLAN technology have been focused mostly on boosting network capacity by means of a more efficient and flexible physical layer. A new concept is required at MAC level to exploit fully the new capabilities of the PHY layer. In this article, we propose a contention mechanism based on Repeated Contentions (ReCo) in frequency domain. It provides a simple-to-configure, robust and short-term fair algorithm for the random contention component of the MAC protocol. The throughput efficiency of ReCo is not sensitive to the number of contending stations, so that ReCo does not require adaptive tuning of the access parameters for performance optimization. Efficiency and robustness is …
Common Misunderstandings of Deterrence Theory in Information Systems Research and Future Research Directions
2022
In the 1980s, information systems (IS) borrowed deterrence theory (DT) from the field of criminology to explain information security behaviors (or intention). Today, DT is among the most commonly used theories in IS security research. Our review of IS research applying DT highlights that many fundamental assumptions of DT are unrecognized and therefore unexamined. This may have resulted in misunderstandings and conceptual confusions regarding some of the basic concepts of DT. For example, some IS studies confuse general deterrence with specific deterrence or do not recognize the difference between the two. Moreover, these fundamental assumptions, when directly examined, may provide importan…
Information Systems Architecture and Technology: Proceedings of 38th International Conference on Information Systems Architecture and Technology – IS…
2018
This three-volume set of books presents advances in the development of concepts and techniques in the area of new technologies and contemporary information system architectures. It guides readers through solving specific research and analytical problems to obtain useful knowledge and business value from the data. Each chapter provides an analysis of a specific technical problem, followed by the numerical analysis, simulation and implementation of the solution to the problem. The books constitute the refereed proceedings of the 2017 38th International Conference “Information Systems Architecture and Technology,” or ISAT 2017, held on September 17–19, 2017 in Szklarska Poręba, Poland. The con…
Design and Realization of a Bidirectional Full Bridge Converter with Improved Modulation Strategies
2020
In this paper a Full-Bridge Converter (FBC) for bidirectional power transfer is presented. The proposed FBC is an isolated DC-DC bidirectional converter, connected to a double voltage source&mdash
Consumer adoption of mobile technologies: a literature review
2015
Although the total number of mobile subscriptions reached 6.8 billion worldwide (ITU, 2013) confirming in the process that mobile technology is widespread, academic literature has so far focused only on explaining adoption of mobile technology and services. This literature review analyses 67 studies from the period 2005-2013 and finds the following: a) most studies are quantitative in nature and come from Asia; b) the Technology Acceptance Model is the most used theory; c) future research should also utilise qualitative methods and examine the behavioural outcomes of mobile adoption instead of simply adoption in consumer markets. peerReviewed
Invited Article: Ultra-broadband terahertz coherent detection via a silicon nitride-based deep sub-wavelength metallic slit
2018
We present a novel class of CMOS-compatible devices aimed to perform the solid-state-biased coherent detection of ultrashort terahertz pulses, i.e., featuring a gap-free bandwidth at least two decades-wide. Such a structure relies on a 1-µm-wide slit aperture located between two parallel aluminum pads, embedded in a 1-µm-thick layer of silicon nitride, and deposited on a quartz substrate. We show that this device can detect ultra-broadband terahertz pulses by employing unprecedented low optical probe energies of only a few tens of nanojoules. This is due to the more than one order of magnitude higher nonlinear coefficient of silicon nitride with respect to silica, the nonlinear material emp…
Supercontinuum Generation and Intermodal Four-Wave Mixing in a Step-Index Few-Mode Fibre
2019
International audience; The complex spatiotemporal dynamics of nonlinear light propagation in multimode fibers (MMFs) has recently witnessed a renewed interest because of their experimental realization in emerging key areas of laser physics and fiber optics [1]. Specifically, MMFs have a number of linear and nonlinear optical properties that make them very attractive to investigate new spatiotemporal effects fundamentally different from standard single-mode fibers. These include the observation of multimode solitons [2], intermodal four-wave mixing (FWM) [3], geometric parametric instabilities [4], spatial beam self-cleaning [5], and the generation of supercontinuum (SC) light when pumping …