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This paper investigates the diversity performance of the on-body fading channels at 2.45 GHz, focusing on the effect of the human body movement. This investigation is based on signal measurements conducted for mobile user cases in both an... more
This paper investigates the diversity performance of the on-body fading channels at 2.45 GHz, focusing on the effect of the human body movement. This investigation is based on signal measurements conducted for mobile user cases in both an anechoic chamber and an indoor office environment, using bodyworn antennas. The effects of the body movement on the fading characteristics of the
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Abstract -A Parallel Method of Moments (PMoM) technique is introduced to analyse electri-cally large planar conducting structures. An integral equation is derived in terms of the in-duced conductivity currents, which is solved using... more
Abstract -A Parallel Method of Moments (PMoM) technique is introduced to analyse electri-cally large planar conducting structures. An integral equation is derived in terms of the in-duced conductivity currents, which is solved using entire domain Galerkin technique, with Chebyshev type ...
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Abstract There are two major advantages of applying High Performance Computing (HPC) to electromagnetic problems. Firstly, to reduce execution times of a given size of problem from days/hours to minutes/seconds. Secondly , the purpose of... more
Abstract There are two major advantages of applying High Performance Computing (HPC) to electromagnetic problems. Firstly, to reduce execution times of a given size of problem from days/hours to minutes/seconds. Secondly , the purpose of this paper, to investigate ...
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In this paper the impact of the position of user's hand holding a multiple-input-multiple-output (MIMO) terminal on system performance and more specifically on channel capacity is investigated. We consider a 4times4 MIMO... more
In this paper the impact of the position of user's hand holding a multiple-input-multiple-output (MIMO) terminal on system performance and more specifically on channel capacity is investigated. We consider a 4times4 MIMO system with a personal digital assistant (PDA) equipped with a compact array of 4 patch elements. Radiation field patterns of the antenna elements in the presence of the
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Recent advances in mobile communications, location/sensing technologies and data processing are boosting the deployment of context-aware services and smart spaces creation. This is reflected in urban environments by the smart-city vision,... more
Recent advances in mobile communications, location/sensing technologies and data processing are boosting the deployment of context-aware services and smart spaces creation. This is reflected in urban environments by the smart-city vision, a city with advanced ICT and surveillance infrastructures offering to citizens a diversity of services. Nevertheless, privacy risks and threats ambush, since collection and process of large amount of personal data occur. Although technology enables the collection of data, its protection against abuse is left to data protection legislation. However, privacy and security requirements, other than being general and abstract terms to be regarded as legislature issues, should be brought down in the technological reality and carefully accounted for in devising technical solutions. In order to limit the disclosure and misuse of citizens' personal data, this report introduces a distributed unit of trust, as a mediating entity that manages, in a privacy ...
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Summary form only given. The notion of quaternions was conceived in the 19th century by the Irish theoretical Physicist G. Hamilton. The initial motivation was a mathematically compact expression of vector rotations in a four-dimensional... more
Summary form only given. The notion of quaternions was conceived in the 19th century by the Irish theoretical Physicist G. Hamilton. The initial motivation was a mathematically compact expression of vector rotations in a four-dimensional space. Quaternions became a subject of theoretical algebra, but they were also used in problems of theoretical physics. In electromagnetics, quaternions have been used very
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... We plan though to exploit this type in the future, in order to enable the definition of conditional roles, and therefore it is mentioned here. ... [17] J.-W. Byun, E. Bertino, N. Li, Purpose Based AccessControl of Complex Data for... more
... We plan though to exploit this type in the future, in order to enable the definition of conditional roles, and therefore it is mentioned here. ... [17] J.-W. Byun, E. Bertino, N. Li, Purpose Based AccessControl of Complex Data for Privacy Protection, in Proceedings of the 10th ACM ...
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Page 1. Privacy Protection in Passive Network Monitoring: an Access Control Approach Georgios V. Lioudakis, Fotios Gogoulos, Anna Antonakopoulou, Dimitra I. Kaklamani, Iakovos S. Venieris School of Electrical and Computer ...
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... An open issue is whether a pure ontology based approach is realistic and feasible with regard ... Also, in future work a performance comparison using other approaches and using the actual ... Council on the protection of individuals... more
... An open issue is whether a pure ontology based approach is realistic and feasible with regard ... Also, in future work a performance comparison using other approaches and using the actual ... Council on the protection of individuals with regard to the processing of personal data and ...
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Page 1. Privacy-Aware Access Control and Authorization in Passive Network Monitoring Infrastructures Fotios Gogoulos, Anna Antonakopoulou, Georgios V. Lioudakis, Aziz S. Mousas, Dimitra I. Kaklamani, Iakovos S. Venieris ...
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Page 1. Visualising Access Control: The PRISM Approach Aziz S. Mousas, Anna Antonakopoulou, Fotios Gogoulos, Georgios V. Lioudakis, Dimitra I. Kaklamani, Iakovos S. Venieris School of Electrical and Computer Engineering ...
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Abstract As privacy is becoming a salient issue for both organizations that provide digital services, as well as their users, access control shifts from traditional role-based models to more sophisticated paradigms that include additional... more
Abstract As privacy is becoming a salient issue for both organizations that provide digital services, as well as their users, access control shifts from traditional role-based models to more sophisticated paradigms that include additional provisions with respect to privacy. ...
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This paper describes a novel single feed dual-band inverted-F antenna (IFA) operating in the ISM and UNNI bands. The antenna is printed on a PC card and is suitable for Bluetooth and wireless LAN 802.11a applications. The... more
This paper describes a novel single feed dual-band inverted-F antenna (IFA) operating in the ISM and UNNI bands. The antenna is printed on a PC card and is suitable for Bluetooth and wireless LAN 802.11a applications. The three-dimensional finite element method (FEM) electromagnetic simulator, HFSS, is used in the design simulation of the IFA/PC card system. The results exhibit a
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ABSTRACT The creation of smart spaces for remote healthcare monitoring is a very prominent example of patients' life improvement by healthcare ICT, eliminating in certain cases the need for hospitalization of patients that require... more
ABSTRACT The creation of smart spaces for remote healthcare monitoring is a very prominent example of patients' life improvement by healthcare ICT, eliminating in certain cases the need for hospitalization of patients that require monitoring. On the other hand, services as such create concerns and are characterized by implications with respect to personal privacy. In order to limit the disclosure and misuse of patients' personal data, this paper discusses the access control solution considered by the inCasa project for the enforcement of fair information practices in the context of remote healthcare monitoring.
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Andy Marsh, Dimitra I. Kaklamani and Konstantinos Adam email marsa@phgasos.ntua.gr, Tel.: +301 7722287, Fax: +301 7723557 Institute of Communications and Computer Systems, National Technical University of Athens 9 Iroon Polytechniou... more
Andy Marsh, Dimitra I. Kaklamani and Konstantinos Adam email marsa@phgasos.ntua.gr, Tel.: +301 7722287, Fax: +301 7723557 Institute of Communications and Computer Systems, National Technical University of Athens 9 Iroon Polytechniou Street, 15773 ...
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... The conducting parts of the antenna (ground plane and rectangular shaped patch) that are made out of ... The bodyworn antennas were worn by an adult male of 75 kg mass and 1.75 m height. ... about 1m/s. For configuration 1, the... more
... The conducting parts of the antenna (ground plane and rectangular shaped patch) that are made out of ... The bodyworn antennas were worn by an adult male of 75 kg mass and 1.75 m height. ... about 1m/s. For configuration 1, the standing still case and the five mobile cases, listed ...
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Page 1. A Proxy for Privacy: the Discreet Box Georgios V. Lioudakis*, Eleftherios A. Koutsoloukas*, Nikolaos Dellas*, Sofia Kapellaki*, George N. Prezerakos*,, Dimitra I. Kaklamani*, Iakovos S. Venieris* * National Technical ...
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When reading a text document, knowledge workers have to "manually" look for additional information: they decide on concepts to further explore, access a Web search engine, form a query and... more
When reading a text document, knowledge workers have to "manually" look for additional information: they decide on concepts to further explore, access a Web search engine, form a query and compose the search results with the original document. In this paper, we propose a framework aiming at transforming electronic documents from passive pieces of information into dynamic entities that search
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The availability of IP traffic monitoring data is of great importance to network operators, researchers and law enforcement agencies. However, privacy legislation, commercial concerns and their implications constitute an impediment in the... more
The availability of IP traffic monitoring data is of great importance to network operators, researchers and law enforcement agencies. However, privacy legislation, commercial concerns and their implications constitute an impediment in the exploitation of such data. ...
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ABSTRACT Remote healthcare monitoring has attracted the interest of many research projects during last years. The need to address the issue of ageing population has lead to the exploitation of modern communication and software... more
ABSTRACT Remote healthcare monitoring has attracted the interest of many research projects during last years. The need to address the issue of ageing population has lead to the exploitation of modern communication and software technologies in this domain too. This is instigated by related technological evolutions such as the evolutions in sensor networks which can now support self organization. This paper presents the INCASA architecture that provides advances towards mainly two directions. To start with, by using the appropriate middleware, it manages to transform the network of devices to a network of services following a Service Oriented Architecture. In this way, it turns the implementation of applications (e.g. clinical applications) on top of the middleware to be easy and efficient. Furthermore, INCASA architecture provides an integrated solution for profiling user habits. This is particularly important in case of elderly people who tend to follow daily activities in a repeating manner. In the proposed architecture, the procedure of modeling user habits is the necessary step in order to generate alert actions in case of divergence.
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The purpose of the study presented in this paper is to investigate the performance of a multicelluar Wideband Code Division Multiple Access (WCDMA) network for different multiuser detection (MUD) strategies in terms of maximum achievable... more
The purpose of the study presented in this paper is to investigate the performance of a multicelluar Wideband Code Division Multiple Access (WCDMA) network for different multiuser detection (MUD) strategies in terms of maximum achievable capacity. Capacity is evaluated both with system level simulations for different loading, as well as with link level simulations for different MUD techniques. Due to
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The coupling of radio frequency power into a semi-infinite lossy tissue medium with an embedded lossy ferrite sphere is analysed. A magnetic loop near the surface of the lossy medium is taken as the external excitation source. The field... more
The coupling of radio frequency power into a semi-infinite lossy tissue medium with an embedded lossy ferrite sphere is analysed. A magnetic loop near the surface of the lossy medium is taken as the external excitation source. The field induced inside the spherical ferrite implant is determined by solving an integral equation. The kernel of this integral equation is the Green's function of the semi-infinite medium and is expressed in terms of Sommerfeld type integrals. Absorbed power densities inside the ferrite spherical implant and the surrounding lossy medium are computed and are compared for several cases. The efficiency of using ferrite implants in hyperthermia applications is examined and conclusions are presented.
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... In order to achieve optimal antenna performance, designers conduct iterative simulations so as to obtain the best values for each ... In order to evaluate the performance of the .distributedoptimization platform, a planar... more
... In order to achieve optimal antenna performance, designers conduct iterative simulations so as to obtain the best values for each ... In order to evaluate the performance of the .distributedoptimization platform, a planar switched-beam antenna array design problem has been ...
Research Interests: Distributed Computing, Object Oriented Programming, Antennas, Computational Electromagnetics, Case Study, and 8 moreComputational Efficiency, Mobile Agent, Programming Paradigm, Computational Grid, Electrical And Electronic Engineering, Simulation Software, Particle Swarm Optimizer, and Radiation Pattern
The radiation of an elementary dipole placed inside an infinite triaxial anisotropic medium is analyzed. A Fourier analysis is employed to compute the field which is represented by using a dyadic formulation. The near and far field... more
The radiation of an elementary dipole placed inside an infinite triaxial anisotropic medium is analyzed. A Fourier analysis is employed to compute the field which is represented by using a dyadic formulation. The near and far field expressions are obtained by pursuing integration of the Fourier integrals. Conventional spherical scalar wave functions are employed to represent the dyadic Green's functien.
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ABSTRACT The recent technological advances are boosting the deployment of context-aware services and smart spaces creation. This is reflected in urban environments by the InfoCity vision, a city with advanced ICT infrastructures, being... more
ABSTRACT The recent technological advances are boosting the deployment of context-aware services and smart spaces creation. This is reflected in urban environments by the InfoCity vision, a city with advanced ICT infrastructures, being the broker for the provision of a diversity of services to the citizens. Nevertheless, privacy risks and threats ambush, since collection and processing of large amount of personal data occur. In order to limit the disclosure and misuse of citizens' personal data, this paper discusses the challenges and solutions for the enforcement of fair information practices in the large scale service architectures of an InfoCity.
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Abstract. The aim of this paper is to demonstrate how multilevel tumour growth and response to therapeutic treatment models can be used in order to simulate clinical trials, with the long-term intention of both better designing clinical... more
Abstract. The aim of this paper is to demonstrate how multilevel tumour growth and response to therapeutic treatment models can be used in order to simulate clinical trials, with the long-term intention of both better designing clinical studies and understanding their outcome based ...
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Research Interests: Cognitive Science, Distributed Computing, Parallel Computing, High Frequency, Performance Evaluation, and 15 moreDynamic Load Balancing, Numerical Simulation, Wireless Network, Electromagnetic Theory, Ray Tracing, Electromagnetic Field, Long Term Evolution, Prediction Model, Task Assignment, Wave propagation, Load Balance, Message Passing Interface, Wireless Communication, Approximation Method, and Geometric Optics
An investigation of the fading experienced by on-body diversity channels at 2.45 GHz is presented by focusing on the effects of the receive antennas position and the human body movement. This investigation is based on the conduction and... more
An investigation of the fading experienced by on-body diversity channels at 2.45 GHz is presented by focusing on the effects of the receive antennas position and the human body movement. This investigation
is based on the conduction and analysis of signal measurements in an indoor
office environment using bodyworn antennas. Three principal combining
techniques, namely selection combining (SC), equal gain combining (EGC)
and maximal ratio combining (MRC) are considered. A statistical characterization of the fading experienced by dual diversity on-body channels is
performed in terms of first and second order statistics. Our investigations
have shown that among several distributions tested, the distribution provides sufficient fit to measured combined signal envelopes and also
offers a good approximation to second order statistics for the majority of
test cases.
is based on the conduction and analysis of signal measurements in an indoor
office environment using bodyworn antennas. Three principal combining
techniques, namely selection combining (SC), equal gain combining (EGC)
and maximal ratio combining (MRC) are considered. A statistical characterization of the fading experienced by dual diversity on-body channels is
performed in terms of first and second order statistics. Our investigations
have shown that among several distributions tested, the distribution provides sufficient fit to measured combined signal envelopes and also
offers a good approximation to second order statistics for the majority of
test cases.