Strength and cardiorespiratory exercises for people with multiple sclerosis (MS)

People with MS experience specific problems that may affect their performance of strength and cardiorespiratory exercises. An understanding of the MS population is required for the successful implementation of such exercises

Ataxia and tremor in people with multiple sclerosis (MS)

Ataxia and tremor are common yet difficult symptoms to manage in people with MS ― often requiring the involvement of a multidisciplinary team. Early intervention is important in order to address both the functional and psychological issues associated with these symptoms

An Efficient Spectral Leakage Filtering for IEEE 802.11af in TV White Space

Orthogonal frequency division multiplexing (OFDM) has been widely adopted for modern wireless standards and become a key enabling technology for cognitive radios. However, one of its main drawbacks is significant spectral leakage due to the accumulation of multiple sinc-shaped subcarriers. In this paper, we present a novel pulse shaping scheme for efficient spectral leakage suppression in OFDM based physical layer of IEEE 802.11af standard. With conventional pulse shaping filters such as a raised-cosine filter, vestigial symmetry can be used to reduce spectral leakage very effectively. However, these pulse shaping filters require long guard interval, i.e., cyclic prefix in an OFDM system, to avoid inter-symbol interference (ISI), resulting in a loss of spectral efficiency. The proposed pulse shaping method based on asymmetric pulse shaping achieves better spectral leakage suppression and decreases ISI caused by filtering as compared to conventional pulse shaping filters

An Inquiry into How iPads are Used in Classrooms

This mixed method study combined the paradigms of quantitative and qualitative research to examine how iPads are used from teachers\u27 perspectives. In the first phase, the researcher collected and analyzed the quantitative data from classroom observations. The second phase consisted of collecting and analyzing the qualitative data to help explain, or elaborate on the quantitative results in the first phase. The researcher utilized a convenient sample of 21 elementary and secondary working teachers who had been using iPads in their classroom at their school in southern Illinois. The findings showed that the majority of teachers did not have any iPad training. They all had to resort to different sources such as self-learning and colleagues\u27 support to learn more about how to integrate the iPad and useful apps into their teaching. There were three practices of iPad use in the classroom. The first practice was that the teachers delivered each iPad to each learner. The second practice was similar to the first practice but the teacher checked out only five or six iPads and distributed each iPad to each group in the classroom. The third practice was that only the teacher used the iPad to deliver the lesson in the classroom. In all cases, the teachers combined the iPad with other technology devices to show the content to the students on the project screen. Students who were taught by the teachers with the iPad mainly worked either individually or in the whole class. In addition, the most common roles the teachers took were lecturing and facilitating when they integrated the iPad into their teaching. The most common level of activities or in-class assignments was knowledge representation equivalent of comprehension level on the Bloom\u27s Taxonomy. Regarding the frequency of iPad use in the classroom, while teachers at public schools sometime used the iPad, their peers at a private school frequently used it. The result also indicated that, according to the teachers, the use of the iPad in the classroom was somewhat useful (2.75 out of 5.00). The average time a teacher spent preparing an iPad-integrated lesson depended on whether he or she had any formal training in iPad use or not. Finally, the teachers observed differences in their students\u27 motivation and/or behaviors when they were learning with the iPad. They were skeptical about whether the use of the iPad had any impact on their students\u27 achievements because there were many variables that could affect their achievements. However, they agreed that the quality of their students\u27 tasks or assignments on the day the iPad was used were better than those on the day the iPad was not used

A Numerical Analysis of Wind Flow in Urban Areas

The high population density in Vietnam create many challenges in its urban development and supply of residential housing. To accommodate the large population, the buildings tend to go vertical and high density to maximize the development ratio in the limited land space and in the conservation of natural geomorphology. The high density of building blocks reduces the permeability for wind penetration. In the extreme case, the housing estate becomes a wind-obstructing structure that could be causing to environmental problems and health hazard due to low level of ventilation follow. So, a better understanding about wind flow in urban areas could help resolve some of the main difficulties that a designer might encounter to improve the geometries of urban areas. Therefore, this article performs the simulation methodology using Computational Fluid Dynamics (CFD) tools in ANSYS FLUENT software to carry out the urban wind environment in the simple planning and design urban areas. The studied parameters were wind velocity 10 m/s in the case of straight wind and in the case of 450-cross wind. CFD is an effective and efficient tool to visualize a flow phenomenon of a particular flow problem. The advanced computational technique could calculate the fluid properties at all points defined within the model domain, providing a complete set of data within the model. However, it is important to highlight that CFD technologies have not been completely reliable as model assumptions are still unavoidable for the present computational technologies to resolve turbulent flows. Understanding the limitations of CFD is crucial to reduce numerical errors and realize possible erroneous data in the model

Research on Aeroelasticity Phenomenon in Aeronautical Engineering

Aeroelasticity phenomena arise when structural deformations induce changes on aerodynamic forces due to airplane structures that are not completely rigid. The additional aerodynamic forces cause an increase in the structural deformations, which leads to greater aerodynamic forces in a feedback process. These interactions may become smaller until reaching a condition of equilibrium or may diverge catastrophically if resonance occurs. Flutter is an instability aeroelasticity phenomenon which is the most difficult to predict. In this chapter, a numerical method and an experimental method were realized to predict aeroelastic response and characteristic parameters of a wing structure. The numerical method was firstly developed based on the interaction between computational fluid dynamic and computational structural dynamic methods using a coupling system, fluid–solid interaction (FSI), in the ANSYS software. Then, an experiment was set up in suitable conditions to study aeroelasticity characteristics with the goal of comparing the numerical results with the experimental results on the same wing structure at low speed. After that, a developed code based on immersed boundary method (IBM) was realized to predict aeroelasticity response and characteristic parameters of the wing structure. AGARD 445.6 wing model was chosen for this developed procedure at high speed. Obtained results were compared to other numerical and experimental results

Outage probability analysis for hybrid TSR-PSR based SWIPT systems over log-normal fading channels

Employing simultaneous information and power transfer (SWIPT) technology in cooperative relaying networks has drawn considerable attention from the research community. We can find several studies that focus on Rayleigh and Nakagami-m fading channels, which are used to model outdoor scenarios. Differing itself from several existing studies, this study is conducted in the context of indoor scenario modelled by log-normal fading channels. Specifically, we investigate a so-called hybrid time switching relaying (TSR)-power splitting relaying (PSR) protocol in an energy-constrained cooperative amplify-and-forward (AF) relaying network. We evaluate the system performance with outage probability (OP) by analytically expressing and simulating it with Monte Carlo method. The impact of power-splitting (PS), time-switching (TS) and signal-to-noise ratio (SNR) on the OP was as well investigated. Subsequently, the system performance of TSR, PSR and hybrid TSR-PSR schemes were compared. The simulation results are relatively accurate because they align well with the theory

Red-emitting Ba2Si5N8Eu2+ conversion phosphor: A new selection for enhancing the optical performance of the in-cup packaging MCW-LEDs

In this research, the influence of the red-emitting Ba2Si5N8Eu2+ convention phosphor on the optical performance of the 7,000K and 7,700K in-cup packaging multi-chip white LEDs (MCW-LEDs) is investigated. The effect of the red-emitting Ba2Si5N8Eu2+ convention phosphor is demonstrated based on Mie Theory by Mat Lab and Light Tools software. The research results indicated that the optical performance of MCW-LEDs was crucially affected by the red-emitting Ba2Si5N8Eu2+ phosphor's concentration. This paper provides an essential recommendation for selecting and developing the phosphor materials for MW-LEDs manufacturing.Web of Science51art. no. 148615

Upper bound limit analysis of plates using a rotation-free isogeometric approach

International audienceThis paper presents a simple and effective formulation based on a rotation-free isogeometric approach for the assessment of collapse limit loads of plastic thin plates in bending. The formulation relies on the kinematic (or upper bound) theorem and namely B-splines or non-uniform rational B-splines (NURBS), resulting in both exactly geometric representation and high-order approximations. Only one deflection variable (without rotational degrees of freedom) is used for each control point. This allows us to design the resulting optimization problem with a minimum size that is very useful to solve large-scale plate problems. The optimization formulation of limit analysis is transformed into the form of a second-order cone programming problem so that it can be solved using highly efficient interior-point solvers. Several numerical examples are given to demonstrate reliability and effectiveness of the present method in comparison with other published methods