185 research outputs found
Past, present and future of information and knowledge sharing in the construction industry: Towards semantic service-based e-construction
The paper reviews product data technology initiatives in the construction sector and provides a synthesis of related ICT industry needs. A comparison between (a) the data centric characteristics of Product Data Technology (PDT) and (b) ontology with a focus on semantics, is given, highlighting the pros and cons of each approach. The paper advocates the migration from data-centric application integration to ontology-based business process support, and proposes inter-enterprise collaboration architectures and frameworks based on semantic services, underpinned by ontology-based knowledge structures. The paper discusses the main reasons behind the low industry take up of product data technology, and proposes a preliminary roadmap for the wide industry diffusion of the proposed approach. In this respect, the paper stresses the value of adopting alliance-based modes of operation
Π ΠΈΡΡΠ°ΠΊΠ½ΡΡΠΈΠΌ Π°ΡΠΎΡΠΈΡΠ°ΡΠΈΠ²Π½ΠΈΠΌ ΠΈΡΡΡΠ°ΠΆΠΈΠ²Π°ΡΠΈΠΌΠ° Π½Π° ΠΠ°ΠΏΠ°Π΄Ρ Ρ 21. Π²Π΅ΠΊΡ ΠΈ ΠΌΠΎΠ³ΡΡΠ½ΠΎΡΡΠΈΠΌΠ° ΡΠΈΡ ΠΎΠ²Π΅ ΠΏΡΠΈΠΌΠ΅Π½Π΅ Ρ (Π΄ΠΎΠΌΠ°ΡΠΎΡ) Π»ΠΈΠ½Π³Π²ΠΈΡΡΠΈΡΠΈ
ΡΠ΄ΡΡΠΈ Π΄Π° ΡΡ Π΄ΠΎΠΌΠ°ΡΠ° Π°ΡΠΎΡΠΈΡΠ°ΡΠΈΠ²Π½Π° ΠΈΡΡΡΠ°ΠΆΠΈΠ²Π°ΡΠ° Π΄ΠΎΡΠ°Π΄Π° Π±ΠΈΠ»Π° ΠΎΠΊΡΠ΅Π½Ρ-ΡΠ° ΠΡΡΠΎΠΊΡ ΠΈ ΡΡΡΠΊΠΎΡ ΡΡΠ°Π΄ΠΈΡΠΈΡΠΈ, ΡΠΈΡ ΡΠ΅ ΠΎΠ²ΠΎΠ³ ΠΏΡΠ΅Π³Π»Π΅Π΄Π° Π΄Π° ΠΏΡΠΈΠΊΠ°ΠΆΠ΅ Π½Π°ΡΠΎΡ ΡΠ°Π²Π½ΠΎΡΡΠΈ ΠΌΠ°ΡΠ΅ ΠΏΠΎΠ·Π½Π°ΡΠ°, Π° ΠΈΠ·ΡΠ°Π·ΠΈΡΠΎ Π·Π°Π½ΠΈΠΌΡΠΈΠ²Π° Π·Π°ΠΏΠ°Π΄Π½Π° ΠΈΡΡΡΠ°ΠΆΠΈΠ²Π°ΡΠ°, ΠΊΠΎΡΠ° Π±ΠΈ ΠΌΠΎΠ³Π»Π° ΠΏΠΎ-ΡΠ»ΡΠΆΠΈΡΠΈ ΠΎΠ²Π΄Π°ΡΡΠΈΠΌ Π»ΠΈΠ½Π³Π²ΠΈΡΡΠΈΠΌΠ° Ρ Π±ΡΠ΄ΡΡΠ½ΠΎΡΡΠΈ. ΠΡΠΎΡΠΈΡΠ°ΡΠΈΡΠ΅ ΡΠ΅ ΠΏΡΠΈΠΌΠ΅ΡΡΡΡ Ρ Π²ΠΈΡΠ΅ Π³ΡΠ°Π½Π° Π΄ΡΡΡΡΠ²Π΅Π½ΠΈΡ
Π½Π°ΡΠΊΠ°, Π°Π»ΠΈ ΠΎΠ²Π΄Π΅ ΡΠ΅ΠΌΠΎ ΡΠ΅ ΡΡΡΠ΅Π΄ΡΡΠ΅Π΄ΠΈΡΠΈ Π½Π° ΠΎΠ±Π»Π°ΡΡΠΈ Π½Π°ΡΠ±Π»ΠΈΠΆΠ΅ Π΄ΠΎΠΌΠ°ΡΠΈΠΌ ΠΈΡΡΡΠ°ΠΆΠΈΠ²Π°ΡΠΈΠΌΠ° ΠΈ Π½Π° ΡΠΈΡ
ΠΎΠ²Π° Π΄ΠΎΡΡΠΈΠ³Π½ΡΡΠ°: ΡΠ΄ΡΡΠΆΠΈΠ²Π°ΡΠ΅ Π°ΡΠΎΡΠΈΡΠ°ΡΠΈΠ²Π½ΠΎΠ³ ΠΌΠ΅ΡΠΎΠ΄Π° Ρ ΠΊΠΎΡΠΏΡΡΠΈΠΌΠ° ΠΈ ΡΠ΅Π³ΠΎΠ²ΠΎ ΠΊΠΎΡΠΈΡΡΠ΅ΡΠ΅ ΠΊΠ°ΠΊΠΎ Π±ΠΈ ΡΠ΅ ΠΎΠ»Π°ΠΊΡΠ°Π»Π° ΠΏΡΠ΅ΡΡΠ°Π³Π° ΡΠ΅ΡΠ½ΠΈΠΊΠ°; ΠΏΡΠΈΠΌΠ΅Π½Π° ΠΎΠ²ΠΎΠ³ ΠΌΠ΅ΡΠΎΠ΄Π° ΠΊΠ°ΠΊΠΎ Π±ΠΈ ΡΠ΅ ΠΈΠ·Π³ΡΠ°Π΄ΠΈΠ»ΠΈ ΠΌΠΎΠ΄Π΅Π»ΠΈ ΠΌΠ΅Π½ΡΠ°Π»Π½ΠΎΠ³ Π»Π΅ΠΊΡΠΈΠΊΠΎΠ½Π°; Π°ΡΠΎΡΠΈΡΠ°-ΡΠΈΡΠ΅ Ρ ΠΏΡΠΈΠΌΠ΅ΡΠ΅Π½ΠΎΡ Π»ΠΈΠ½Π²Π³ΠΈΡΡΠΈΡΠΈ, Ρ Π°Π½Π°Π»ΠΈΠ·Π°ΠΌΠ° Π²Π΅Π·Π°Π½ΠΈΠΌ Π·Π° ΡΡΠ²Π°ΡΠ°ΡΠ΅ ΡΡΡΠ°Π½ΠΎΠ³ ΡΠ΅Π·ΠΈΠΊΠ°
Approach for GDPR Compliant Detection of COVID-19 Infection Chains
While prospect of tracking mobile devices' users is widely discussed all over
European countries to counteract COVID-19 propagation, we propose a Bloom
filter based construction providing users' location privacy and preventing mass
surveillance. We apply a solution based on Bloom filters data structure that
allows a third party, a government agency, to perform some privacy-preserving
set relations on a mobile telco's access logfile. By computing set relations,
the government agency, given the knowledge of two identified persons, has an
instrument that provides a (possible) infection chain from the initial to the
final infected user no matter at which location on a worldwide scale they are.
The benefit of our approach is that intermediate possible infected users can be
identified and subsequently contacted by the agency. With such approach, we
state that solely identities of possible infected users will be revealed and
location privacy of others will be preserved. To this extent, it meets General
Data Protection Regulation (GDPR)requirements in this area
Evaluation of ultra-wideband in vivo radio channel and its effects on system performance
This paper presents bitβerrorβrate (BER) performance analysis and improvement using equalizers for an in vivo radio channel at ultraβwideband frequencies (3.1 GHz to 10.6 GHz). By conducting simulations using a bandwidth of 50 MHz, we observed that the in vivo radio channel is affected by smallβscale fading. This fading results in intersymbol interference affecting upcoming symbol transmission, causing delayed versions of the symbols to arrive at the receiver side and causes increase in BER. A 29βtaps channel was observed from the experimentally measured data using a human cadaver, and BER was calculated for the measured in vivo channel response along with the ideal additive white Gaussian noise and Rayleigh channel models. Linear and nonlinear adaptive equalizers, ie, decision feedback equalizer (DFE) and least mean square (LMS), were used to improve the BER performance of the in vivo radio channel. It is noticed that both the equalizers improve the BER but DFE has better BER compared to LMS and shows the 2βdB and 4βdB performance gains of DFE over the LMS at Eb/No = 12 dB and at Eb/No = 14 dB, respectively. The current findings will help guide future researchers and designers in enhancing systems performance of an ultraβwideband in vivo wireless systems
Air Force Institute of Technology Research Report 2009
This report summarizes the research activities of the Air Force Institute of Technologyβs Graduate School of Engineering and Management. It describes research interests and faculty expertise; lists student theses/dissertations; identifies research sponsors and contributions; and outlines the procedures for contacting the school. Included in the report are: faculty publications, conference presentations, consultations, and funded research projects. Research was conducted in the areas of Aeronautical and Astronautical Engineering, Electrical Engineering and Electro-Optics, Computer Engineering and Computer Science, Systems and Engineering Management, Operational Sciences, Mathematics, Statistics and Engineering Physics
An Algorithm based on VANET Technology to Count Vehicles Stopped at a Traffic Light
Vehicular Ad hoc Networks (VANETs) have gained considerable attention in the past few years due to their promising applicability in relation to the Intelligent Transportation Systems (ITSs). This emerging new technology will provide timely information to develop adaptive traffic light control systems that will allow a significant optimization of the vehicular traffic flow. In this paper, we introduce a novel algorithm for counting vehicles stopped at a traffic light using VANET technology. The algorithm is based on the idea of the propagation of a count request message from the RSU (originating unit) toward the vehicles that are at the end of the waiting line, and the propagation of a response message (with the number of vehicles counted) in the opposite direction, that is, from the vehicles at the end of the line toward the RSU. For this, our algorithm uses BEACON messages periodically to exchange the necessary information between any two 1-hop neighbors. Using the data received from BEACON messages, each vehicle can maintain its own neighbors list. To validate and evaluate the performance of our proposal, we use Veins (Vehicle in Network Simulation) and TraCI (Traffic Control Interface). The former is a framework that ties together a network simulator (OMNeT++) with a road traffic simulator (SUMO), and the latter is an API for the communications between both simulators by providing TCP connections between each other. The results of the simulations performed in different scenarios are encouraging since they indicate that the proposed algorithm efficiently computes a number of vehicles very close to the real one, using a few control messages
Joint relay selection and bandwidth allocation for cooperative relay network
Cooperative communication that exploits multiple relay links offers significant performance improvement in terms of coverage and capacity for mobile data subscribers in hierarchical cellular network. Since cooperative communication utilizes multiple relay links, complexity of the network is increased due to the needs for efficient resource allocation. Besides, usage of multiple relay links leads to Inter- Cell Interference (ICI). The main objective of this thesis is to develop efficient resource allocation scheme minimizes the effect of ICI in cooperative relay network. The work proposed a joint relay selection and bandwidth allocation in cooperative relay network that ensures high achievable data rate with high user satisfaction and low outage percentage. Two types of network models are considered: single cell network and multicell network. Joint Relay Selection and Bandwidth Allocation with Spatial Reuse (JReSBA_SR) and Optimized JReSBA_SR (O_JReSBA_SR) are developed for single cell network. JReSBA_SR considers link quality and user demand for resource allocation, and is equipped with spatial reuse to support higher network load. O_JReSBA_SR is an enhancement of JReSBA_SR with decision strategy based on Markov optimization. In multicell network, JReSBA with Interference Mitigation (JReSBA_IM) and Optimized JReSBA_IM (O_JReSBA_IM) are developed. JReSBA_IM deploys sectored-Fractional Frequency Reuse (sectored- FFR) partitioning concept in order to minimize the effect of ICI between adjacent cells. The performance is evaluated in terms of cell achievable rate, Outage Percentage (OP) and Satisfaction Index (SI). The result for single cell network shows that JReSBA_SR has notably improved the cell achievable rate by 35.0%, with reduced OP by 17.7% compared to non-joint scheme at the expense of slight increase in complexity at Relay Node (RN). O_JReSBA_SR has further improved the cell achievable rate by 13.9% while maintaining the outage performance with reduced complexity compared to JReSBA_SR due to the effect of optimization. The result for multicell network shows that JReSBA_IM enhances the cell achievable rate up to 65.1% and reduces OP by 35.0% as compared to benchmark scheme. Similarly, O_JReSBA_IM has significantly reduced the RN complexity of JReSBA_IM scheme, improved the cell achievable rate up to 9.3% and reduced OP by 1.3%. The proposed joint resource allocation has significantly enhanced the network performance through spatial frequency reuse, efficient, fair and optimized resource allocation. The proposed resource allocation is adaptable to variation of network load and can be used in any multihop cellular network such as Long Term Evolution-Advanced (LTE-A) network
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