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Kottou S.,National and Kapodistrian University of Athens | Nikolopoulos D.,Technological Educational Institute of Piraeus | Yannakopoulos P.H.,Technological Educational Institute of Piraeus | Petraki E.,Technological Educational Institute of Piraeus | And 2 more authors.
Physica Medica | Year: 2015

The main purpose of this work was to investigate the fluctuation of Greek indoor electromagnetic field (EMF) intensity values and identify peaks that might occur. The scientific interest is mainly focused on the bands of extremely low-frequency (ELF) magnetic fields and radiofrequency (RF) electric fields which have been suggested to be possibly carcinogenic to humans by the Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR).Electromagnetic radiation (EMR) measurements were performed in a variety of indoor dwellings, in Attica and in the islands of Zakynthos and Lesvos.A total number of 4540 measurements were taken in a wide frequency range (50 Hz-2100 MHz) of which 3301 in Attica, 963 in Lesvos and 276 in Zakynthos.Statistical analysis of the data revealed specific statistically significant differences between the mean values of the electric (ELF and RF) but not the magnetic (ELF) field strengths measured at different distances from the EMF source, as well as between some of the mean values of the RF electric field at different bands. Some statistically significant differences between mean electric field values at different geographic locations were also identified.As far as the RF electric field is concerned, the maximum values, in most cases, were below 0.5 V/m, however increased values above 1 V/m and up to 5.6 V/m were occasionally observed. The ELF magnetic field values were lower than 1 μT. It may be concluded that overall, the observed indoor EMF intensity values remained well below domestic and European established limits. © 2015 Associazione Italiana di Fisica Medica.


PubMed | NEO Tech, Technological Educational Institute TEI of Western Greece, Technological Educational Institute of Piraeus and National and Kapodistrian University of Athens
Type: Journal Article | Journal: Physica medica : PM : an international journal devoted to the applications of physics to medicine and biology : official journal of the Italian Association of Biomedical Physics (AIFB) | Year: 2015

The main purpose of this work was to investigate the fluctuation of Greek indoor electromagnetic field (EMF) intensity values and identify peaks that might occur. The scientific interest is mainly focused on the bands of extremely low-frequency (ELF) magnetic fields and radiofrequency (RF) electric fields which have been suggested to be possibly carcinogenic to humans by the Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR). Electromagnetic radiation (EMR) measurements were performed in a variety of indoor dwellings, in Attica and in the islands of Zakynthos and Lesvos. A total number of 4540 measurements were taken in a wide frequency range (50 Hz-2100 MHz) of which 3301 in Attica, 963 in Lesvos and 276 in Zakynthos. Statistical analysis of the data revealed specific statistically significant differences between the mean values of the electric (ELF and RF) but not the magnetic (ELF) field strengths measured at different distances from the EMF source, as well as between some of the mean values of the RF electric field at different bands. Some statistically significant differences between mean electric field values at different geographic locations were also identified. As far as the RF electric field is concerned, the maximum values, in most cases, were below 0.5 V/m, however increased values above 1 V/m and up to 5.6 V/m were occasionally observed. The ELF magnetic field values were lower than 1 T. It may be concluded that overall, the observed indoor EMF intensity values remained well below domestic and European established limits.


Papoulis D.,University of Patras | Komarneni S.,Pennsylvania State University | Panagiotaras D.,Technological Educational Institute TEI of Western Greece | Stathatos E.,Technological Educational Institute TEI of Western Greece | And 7 more authors.
Applied Catalysis B: Environmental | Year: 2014

For the first time two different nanoclay minerals were combined with nanophase anatase for the synthesis of three-phase nanocomposites with improved photocatalytic properties. The novel halloysite (H)+palygorskite (Pal)-TiO2 nanocomposites were prepared using palygorskite and halloysite from Greece. Three nanocomposites were synthesized using [Hal+Pal] to TiO2 mass ratios of [10+20]:70, [15+15]:70 and [20+10]:70, respectively by depositing anatase form of TiO2 on the clay surfaces using titanium isopropoxide as a precursor under hydrothermal treatment at 180°C. Phase composition, particle morphology and physical properties of these three-phase nanocomposites were characterized by XRD, ATR-FTIR, SEM, TEM, DR-UV-Vis, N2-adsorption/desorption isotherms. The photocatalytic activities of three-phase clay-titania nanocomposites in decomposing NOx gas and toluene vapor were determined. The three-phase clay-titania nanocomposites showed significantly higher photocatalytic activity in decomposing inorganic and organic pollutants compared to that of either palygorskite- or halloysite-TiO2 nanocomposites under both UV- and visible-light irradiation. These studies led to a new class of clay-based nanocomposite materials with advanced photocatalytic properties. © 2013 Elsevier B.V.


Stanev D.,University of Patras | Moustakas K.,University of Patras | Gliatis J.,University of Patras | Koutsojannis C.,Technological Educational Institute TEI of Western Greece
Methods of Information in Medicine | Year: 2016

Introduction: This article is part of the Focus Theme of Methods of Information in Medicine on “Methodologies, Models and Algorithms for Patients Rehabilitation”. Objectives: The objective of the proposed approach is to develop a clinical decision support system (DSS) that will help clinicians optimally plan the ACL reconstruction procedure in a patient specific manner. Methods: A full body model is developed in this study with 23 degrees of freedom and 93 muscles. The knee ligaments are modeled as non-linear spring-damper systems and a tibiofemoral contact model was utilized. The parameters of the ligaments were calibrated based on an optimization criterion. Forward dynamics were utilized during simulation for predicting the model’s response to a given set of external forces, posture configuration and physiological parameters. Results: The proposed model is quantified using MRI scans and measurements of the well-known Lachman test, on several patients with a torn ACL. The clinical potential of the proposed framework is demonstrated in the context of flexion-extension, gait and jump actions. The clinician is able to modify and fine tune several parameters such as the number of bundles, insertion position on the tibia or femur and the resting length that correspond to the choices of the surgical procedure and study their effect on the biomechanical behavior of the knee. Conclusion: Computational knee models can be used to predict the effect of surgical decisions and to give insight on how different parameters can affect the stability of the knee. Special focus has to be given in proper calibration and experimental validation. © Schattauer 2016.


Papoulis D.,University of Patras | Komarneni S.,Pennsylvania State University | Panagiotaras D.,Technological Educational Institute TEI of Western Greece
Clay Minerals | Year: 2014

Trachyandesite rocks, occurring over an area of about 1 km2 in the southwest part of Limnos Island, Greece, are altered mainly to halloysite. The samples were collected and analysed by polarizing microscopy, powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and chemical analysis. The alteration of plagioclase to halloysite follows seven discrete stages that are described in detail. The geochemical evaluation of the data shows enrichment of the light REE (LREE) over heavy REE (HREE) as expressed by the (La/Yb)n ratio. The SLREE range from 206.44 to 272.30, while the sum of HREE varies from 11.01 to 26.26. The (La/Yb)n ratio ranges from 9.72 to 27.64. Fractionation among LREE expressed as (La/Sm)n and between middle REE (MREE) and HREE is shown as (Tb/Yb)n ratios. The most altered rocks close to the fault zone have high (Tb/Yb)n ratios and low (La/Sm)n and Eu/Eu ratios. Although mineralogy and clay mineral textures indicate hydrothermal genesis of halloysite, the geochemical data are not conclusive due to a secondary weathering effect. © 2014 The Mineralogical Society.


PubMed | Queen Margaret University, Technological Educational Institute TEI of Western Greece and University of Patras
Type: Journal Article | Journal: Physiotherapy | Year: 2016

Total knee replacement (TKR) has a beneficial effect on patients functional ability; however, incidence of falls and deficits on proprioception are not restored even 1-year after surgery. Early and intensive exercise post-TKR has received limited endorsement in the literature. The aim of this review was to systemically identify and critically appraise clinical studies investigating the effect of sensori-motor training on functional and balance performance in TKR patients.The electronic databases Cochrane Library, MEDLINE, EMBASE, CINAHL, PEDro and the register of current controlled trials were searched up to September 2014.Two independent reviewers used predefined inclusion and exclusion criteria to identify all eligible articles. Eligible articles were summarized and critically reviewed, using the PEDro scale.Two hundred and seventy six articles were screened, six were included. The studies, presented the results of 409 patients (269 intervention, 140 control). A range of rehabilitation protocols were defined by components of proprioception, postural control, balance perturbation and coordination. All studies supported the use of sensori-motor training as an additional element in patients rehabilitation protocols. Clinical performance-based tests (more than relevant patient-reported measures) showed that functional ability and balance were improved compared to controls. The robustness of evidence was compromised because most of the studies were underpowered.Limited robust (Ia) evidence supports the equal effectiveness of functional rehabilitation program as a functional rehabilitation enhanced with sensori-motor elements in patients post-TKR. However, dose-response parameters of exercise eliciting improvement warrant further investigation.


Solomou G.,Hellenic Open University | Pierrakeas C.,Hellenic Open University | Pierrakeas C.,Technological Educational Institute TEI of Western Greece | Kameas A.,Hellenic Open University
Educational Technology and Society | Year: 2015

The ability to effectively administrate educational resources in terms of accessibility, reusability and interoperability lies in the adoption of an appropriate metadata schema, able of adequately describing them. A considerable number of different educational metadata schemas can be found in literature, with the IEEE LOM being the most widely known; however, it is often the case where it cannot fully accommodate the characteristics of several types of educational resources, that's why application profiles have been proposed. Each metadata standard and application profile usually comes with a different (either less or more semantically enriched) binding, thus allowing the retrieval and dissemination of resources with varying degrees of effectiveness. In this work, we propose an application profile of the IEEE LOM standard having special focus on distance learning material, while being generic enough so as to be applicable to any educational material and application. We then present an ontology model for this profile that aims to improve the potential discovery and retrieval of educational resources within intelligent e-learning environments.


PubMed | Technological Educational Institute TEI of Western Greece and 2 Clinical and Sports Physiotherapist
Type: | Journal: Journal of sport rehabilitation | Year: 2016

Elastic bandages are commonly used in sports to treat and prevent sports injuries.To conduct a systematic review assessing the effectiveness of elastic bandaging in orthopedic and sports injuries prevention and rehabilitation.We searched the following electronic databases: MEDLINE, CINAHL, SPORTDiscus, EMBASE and Physiotherapy Evidence Database (PEDro), with key words elastic bandaging in combination, respectively, with (1) first aid, (2) sports injuries, (3) orthopedic injuries and (4) sports injuries prevention and rehabilitation. Research studies were selected based upon the use of the term elastic bandaging in the abstract. Final selection was made by applying inclusion and exclusion criteria to the full text. Studies were included if they were English, peer-reviewed clinical trials on the effects of elastic bandaging for orthopedic injuries prevention and rehabilitation.Twelve studies met the above criteria and were included in the final analysis. Data collected included number of participants, condition being treated, treatment used, control group, outcome measures and results. Studies were critically analyzed using the PEDro scale.The studies in this review fell into two (2) categories: studies in athletes (N=2) and non-athletes (N=10). All included trials had moderate-to-high quality, scoring (5 on the PEDro scale). The PEDro scores for the studies in athletes and non-athletes ranged from 5 to 6 out of 10 and from 5 to 8 out of 10, respectively. The quality of studies was mixed, ranging from higher to moderate methodological quality clinical trials. Overall, elastic bandaging can assist proprioceptive function of knee and ankle joint. Because of the moderate methodological quality and insufficient number of clinical trials, further effects of the elastic bandaging could not be confirmed.


Louvros S.,Technological Educational Institute TEI of Western Greece | Paraskevas M.,Technological Educational Institute TEI of Western Greece
Computers and Electrical Engineering | Year: 2014

Estimating average throughput and packet transmission delay for worst case scenario (cell edge users) is crucial for LTE cell planners in order to preserve strict QoS for delay sensitive applications. Cell planning techniques emphasize mostly on cell range (coverage) and throughput predictions but not on delay. Cell edge users mostly suffer from throughput reduction due to bad coverage and consequently unexpected uplink transmission delays. To estimate cell edge throughput a common practice on international literature is the use of simulation results. However simulations are never accurate since MAC scheduler is a vendor specific software implementation and not 3GPP explicitly specified. This paper skips simulations and proposes an IP transmission delay and average throughput analytical estimation using mathematical modeling based on probability delay analysis, thus offering to cell planners a useful tool for analytical estimation of uplink average IP transmission. © 2014 Elsevier Ltd. All rights reserved.


Bisdounis L.,Technological Educational Institute Tei Of Western Greece
2016 5th International Conference on Modern Circuits and Systems Technologies, MOCAST 2016 | Year: 2016

This paper presents the physical implementation of the digital part of an OFDM-based baseband modem for point-to-multipoint fixed broadband wireless access (FBWA) solutions. It is compliant with the corresponding IEEE 802.16 standard and compatible to a fixed WiMAX profile. The adopted realization approach is based on an array of processing elements belonging to a case of computing systems characterized by having hundreds of embedded processing elements and memories (massively parallel processor arrays). The approach offers the performance, the computational density and the programmability needed for the implementation of modern wireless communication systems. © 2016 IEEE.

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