0.6 Tb/s-km multimode fibre feasibility - Experimant using 40 channel DWDM over Quadrature-Subcarrier channels

Peer reviewe

Towards terabit-per-second capacities over rmultimode fibre links using SCM/WDM techniques

Peer reviewe

Cooperative uplink Inter-cell interference (ICI) mitigation in 5G Fibre Wireless (FiWi) Networks

This paper presents a novel cooperative uplink inter-cell interference (ICI) mitigation algorithm based on joint reception at the base station using receiver adaptive beamforming in a Cloud Radio Access Network (CRAN). In extension the proposed algorithm exploits global network view of the centralised processing unit within the central office providing an attractive solution for Fibre-Wireless (FiWi) network infrastructures. Centralised processing allows for joint scheduling decisions for individual mobile users to be made based on the information received from different cells. As a result, uplink user transmission is scheduled according to the known positions of other users in order to minimise ICI. This is enhanced in operation by an advanced receiver beamforming technique that in corporation has the potential to improve the overall uplink capacity. Therefore the benefits of receiving uplink signals from a larger number of antennas, in different geographical locations, are investigated using the proposed techniques of FiWi uplink joint reception and coordinated scheduling. System level simulations have demonstrated significant improvement in mobile user throughput and received signal-to-interference-noise-ratio (SINR

Psychometric evaluation of the Rosenberg Self-Esteem Scale in primary school students with mild intellectual disability: First evidence

Background: Although the Rosenberg Self-Esteem Scale (RSES) is the most widely used measure of self-esteem, the evidential basis to confirm the RSES factor validity and reliability in children with intellectual disabilities (ID) has not been previously addressed. The purpose of this study was to evaluate the psychometric properties of the Greek version of the RSES into a sample consisting of primary school students with mild ID, bearing in mind the aspect of multidimensionality. In addition, gender differences were also investigated. Methods: The participants were 103 primary school students with mild ID aged 9–12 years old. Fifty-four (52.4 %) of the participants were boys and forty-nine were girls (47.6 %). Using the LISREL software, six different models of factor structure were estimated. The psychometric properties of the RSES, including internal consistency, content validity, convergent and discriminant validity as well as confirmatory factor analysis, were assessed. Results: The findings of this study provide some preliminary support to the robustness of the bifactor model, with a general self-esteem factor and two method effect factors that capture the direction of positive and negative item wording. Conclusions: Although it is inappropriate to conclude that the results will be extended to all other populations and cultures, it can be assumed that bifactor models, which specify method effects due to wording, fit better than strictly unidimensional or two factor models. © 2021 Elsevier Lt

Dimensionality of the rosenberg self-esteem scale among greek primary school students

The aim of the current study was to validate the self-report version of the Rosenberg Self-Esteem Scale (RSES; Rosenberg, 1965) structure in a sample of Greek primary school students. The study was based on the original one-factor model suggested by the scale's author, as well as on the two-factor correlated model of positive and negative items. Participants were 652 primary school students (N=652, M=10.02, SD=1.160). The psychometric properties of the RSES were assessed by conducting a Confirmatory Factor Analysis (CFA). Both average variance extracted and composite reliability were used to test the internal consistency and convergent validity. The correlated two-factor model provided a better fit to the data than the one-factor model, according to the CFA. This conclusion is based on the analysis results, which comprised as providing good fit if non-significant X2 values, X2 /df 0.90), as well as the root mean square error of approximation (RMSEA) < 0.06 (Hu & Bentler, 1999). The main contribution of this study was the adaptation and evaluation of the RSES for use of Greek students and the determination of its factor structure. Teachers and researchers could also use this interpreted scale to determine the level of self-esteem in primary school children and form strategies to increase their self-esteem. © 2021 Eskisehir Osmangazi University. All rights reserved

Motor and cognitive performance differences between children with and without developmental coordination disorder (DCD)

The current study adopts the PASS theory of information processing to investigate the probable differences in specific motor and cognitive abilities between children with and without developmental coordination disorder (DCD). Participants were 108 5- and 6-year-old preschoolers (54 children with DCD and 54 children without DCD). The Movement Assessment Battery for Children assessed motor function. Running speed and agility were measured using the Bruininks-Oseretsky Test of Motor Proficiency. Finally, the Planning, Attention and Simultaneous Scales from the Das-Naglieri Cognitive Assessment System evaluated cognitive ability. Children with DCD differed significantly from those without DCD performing at a lower level on all motor and cognitive tasks. A correlation analysis revealed significant relationships between cognitive processes and motor skills. Simultaneous cognitive processing and manual dexterity were significantly correlated for both groups. Furthermore, a significant relationship was revealed between planning cognitive processing and balance for the non-DCD group. Thus, early assessment might identify specific cognitive-motor difficulties. Furthermore, early intervention might prevent some of the developmental comorbidities in the academic and everyday lives of children with movement difficulties. © 2012 Elsevier Ltd

The presence, enjoyment, mood experience, attitude and preference towards exergames scale in children with mild intellectual disability

Purpose: The purpose of this study was to examine the factor structure and cross-cultural validity of the self-report questionnaire of Ho, Lwin, Sng & Yee (2017) in a sample of Greek primary school students with mild intellectual disability (ID) using VR exergames. The questionnaire consisted of five scales, namely self-presence, mood experience, game enjoyment, attitude toward exergames and preference for future gameplay. Methods: Participants were 103 primary school students with mild ID aged 9–12 years old (males = 52.4%, females = 47.6%). Confirmatory Factor Analysis was undertaken through structural equation modelling to determine factorial validity. Convergent validity and internal consistency were calculated by considering the average variance extracted and the composite reliability respectively, while discriminant validity was estimated by maximum shared squared variance. Results: Results indicated that the model was a good fit for the data as soon as seven items were dropped from the scale because of presenting poor consistency. Instrument was shown to have good internal consistency, appropriate convergent and discriminant validity. Conclusion: Evidence was found in support of the psychometric integrity of the Ho, Lwin, Sng & Yee (2017) questionnaire when implemented to children with mild ID. © 2021, The Author(s), under exclusive licence to Springer-Verlag Italia S.r.l., part of Springer Nature

Cooperative 5G Switched and adaptive receiver beamforming for fibre wireless networks

This paper introduces an eNodeB receiver beamforming technique to mitigate future 5G network uplink inter-cell interference. This technique is based on the concept of smart antennas, improving the uplink signal-to-interference noise ratio (SINR) of cell-edge User Equipment (UEs). Antenna adaptivity in the proposed technique is complemented by the presence of switched antenna beamforming applicable to selective cluster UEs saving on processing power at the eNodeB. The benefits of cooperative uplink receiver beamforming can be enhanced in fibre-wireless (FiWi) networks with centralization due to a better knowledge of UE position and resource allocation. System level simulations of a complete cellular network have demonstrated significant improvement in the presence of switched and adaptive beamforming with respect to throughput and SIN

Археологическое наследие в современном общественном сознании жителей Томска

This paper presents ACCORDANCE, a novel ultra-high capacity extended reach optical access network architecture based on OFDMA technology/protocols, implemented through the proper mix of state-of-the-art photonics and electronics. Such architecture is not only intended to offer improved performance compared to evolving TDMA-PON solutions but also provide the opportunity for convergence between optical, radio and copper-based access. Although OFDM has been used in radio and copper-based communications, it is only recently that is making its way into optics and is expected to increase the system reach and transmission rates without increasing the required cost/complexity of optoelectronic components. ACCORDANCE hence aims to realize the concept of introducing OFDMA-based technology and protocols (Physical and MAC layer) to provide a variety of desirable characteristics, such as increased aggregate bandwidth and scalability, enhanced resource allocation flexibility, longer reach, lower equipment cost/complexity and lower power consumption, while also supporting multi-wavelength operation. In addition, it enables the convergence of the optical infrastructure with standard wireless solutions, thus offering a way to integrate dominant wired and wireless technologies in a hybrid access network supporting seamless ubiquitous broadband services

The influence of a short intervention program on early childhood and physical education teachers' ability to identify children with developmental coordination disorders

The purpose of this study was to assess the effectiveness of a short intervention program designed to enhance the educators' ability to identify children with developmental coordination disorder (DCD). Twenty early childhood and 20 physical education teachers (n = 40) participated in the study. Participants were randomly assigned into an experimental group (n = 20) and a control group (n = 20). A 3-week intervention program implemented, which comprised of four 2-hour lectures and two practice sections of the same duration and focused on the issue of DCD within the educational setting. After the completion of the program, each educator evaluated four children's motor performance using the Movement Assessment Battery for Children Checklist (Sugden & Sugden, 1991). Subsequently, another assessment took place using the Movement Assessment Battery for Children. The total number of evaluated children was 160. Results showed that the educators who attended the educational program showed higher identification ability. No significant differences were found between physical education and early childhood teachers of the experimental group. On the contrary, in the control group, early childhood teachers exhibited higher identification ability than the physical education teachers. The intervention program significantly enhanced the educators' ability to identify children with DCD. The implication of this study is that the education of school professionals should be a continuous process