Search results for "Random"

Efficacy of chlorhexidine, hydrogen peroxide and tulsi extract mouthwash in reducing halitosis using spectrophotometric analysis : a randomized contr…

2019

Background To evaluate the efficacy of tulsi extract mouthrinse in reducing halitosis as compared to chlorhexidine and hydrogen peroxide mouthrinses using spectrophotometric analysis. Material and methods It was a parallel, single center, double blinded randomized controlled trial of 15 days duration. A total of 300 participants were screened, out of which 45 subjects those fulfilled inclusion criteria of age range 17-35 years were included in the trial. The participants were randomly provided with tulsi, hydrogen peroxide or chlorhexidine mouthwashes (control group) to use 10 ml twice daily for 15 days. Clinical measurements were taken at baseline and 15 days using arbitrary 0-5 scale for …

The Influence of Friction on Design of the Type of Bracket and Its Relation to OHRQoL in Patients Who Use Multi-Bracket Appliances: A Randomized Clin…

2021

Background and objectives: The aim of this study was to evaluate the influence of friction on design of the type of bracket, patients’ perception of pain and the impact on their oral health-related quality of life. Materials and Methods: A randomized clinical trial was carried out with 90 patients (62.2% women and 37.8% men) with three kinds of fixed multi-bracket appliances: Conventional (GC), fixed multi-bracket low friction (GS) and self-ligating (GA). The VAS (Visual Analogue Scale) was used to determine pain during the first seven days of treatment at different points in time. The patients were also given the OHIP-14 (Oral Health Impact Profile) questionnaire to analyse their oral heal…

A geometric street scattering channel model for car-to-car communication systems

2011

This paper presents a geometric street scattering channel model for car-to-car (C2C) communication systems under line-of-sight (LOS) and non-LOS (NLOS) propagation conditions. Starting from the geometric model, we develop a stochastic reference channel model, where the scatterers are uniformly distributed in rectangles in the form of stripes parallel to both sides of the street. We derive analytical expressions for the probability density functions (PDFs) of the angle-of-departure (AOD) and the angle-of-arrival (AOA). We also investigate the Doppler power spectral density (PSD) and the autocorrelation function (ACF) of the proposed model, assuming that the mobile transmitter (MT) and the mo…

Management of uncertain pairwise comparisons in AHP through probabilistic concepts

2019

Abstract Fast and judicious decision-making is paramount for the success of many activities and processes. However, various degrees of difficulty may affect the achievement of effective and optimal solutions. Decisions should ideally meet the best trade-off among as many of the involved factors as possible, especially in the case of complex problems. Substantial cognitive and technical skills are indispensable, while not always sufficient, to carry out optimal evaluations. One of the most common causes of wrong decisions derives from uncertainty and vagueness in making forecasts or attributing judgments. The literature shows numerous efforts towards the optimization and modeling of uncertai…

Priority-based initial access for URLLC traffic in massive IoT networks: Schemes and performance analysis

2020

Abstract At a density of one million devices per square kilometer, the10’s of billions of devices, objects, and machines that form a massive Internet of things (mIoT) require ubiquitous connectivity. Among a massive number of IoT devices, a portion of them require ultra-reliable low latency communication (URLLC) provided via fifth generation (5G) networks, bringing many new challenges due to the stringent service requirements. Albeit a surge of research efforts on URLLC and mIoT, access mechanisms which include both URLLC and massive machine type communications (mMTC) have not yet been investigated in-depth. In this paper, we propose three novel schemes to facilitate priority-based initial …

Second Harmonic Generation via Random Quasi-phase Matching in a Periodically Poled Lithium Tantalate Waveguide

2011

We observe second harmonic generation via random quasi phase matching in a 1.5μm periodically poled lithium tantalate. The presence of a slab waveguide allows the comparison between bulk and guided wave configurations.

Gender Peer Effects in University: Evidence from a Randomized Experiment

2010

Recent studies for primary and secondary education find positive effects of the share of girls in the classroom on achievement of boys and girls. This study examines whether these results can be extrapolated to post-secondary education. We conduct an experiment in which the shares of girls in workgroups for first year students in economics and business are manipulated and students are randomly assigned to these groups. Boys tend to postpone their dropout decision when surrounded by more girls, and there is also a modest reduction in early absenteeism. On the other hand, boys perform worse on courses with high math content when assigned to a group with many girls. Overall, however, we fail t…

2021

European children and adolescents spend most of their daily life and especially their school hours being sedentary which may increase their risk for chronic non-communicable diseases later in life. After the curriculum reform of Finnish basic education in 2014, most of the new or renovated comprehensive schools in Finland incorporate open and flexible classroom designs. Their open learning spaces may provide students opportunities to reduce sedentary behavior during school hours. Thus, waist-worn accelerometers were used to assess classroom-based sedentary time (ST), the number of breaks from sedentary time (BST), and physical activity (PA) among cross-sectional samples of 3rd and 5th grade…

The UP4FUN intervention effect on overall sedentary time and breaking up sedentary time in Belgian children (10–12 years): The ENERGY-project

2014

Introduction Within the ENERGY-project [1] , a school-based intervention to reduce and to break up sedentary time (UP4FUN) was developed for children aged 10 to 12 years. This study examined the UP4FUN intervention effect on objectively measured overall sedentary time and sedentary pattern variables among Belgian children. Sedentary pattern variables included number of breaks in sedentary time, number of sedentary bouts (≥ 10 minutes) and total and average amount of time spent in those sedentary bouts. Methods The six weeks intervention was tested in a randomized controlled trial with pre-test post-test design with five intervention and five control schools in Belgium. The total sample incl…

Hidden Markov Random Fields and Direct Search Methods for Medical Image Segmentation

2016

The goal of image segmentation is to simplify the representation of an image to items meaningful and easier to analyze. Medical image segmentation is one of the fundamental problems in image processing field. It aims to provide a crucial decision support to physicians. There is no one way to perform the segmentation. There are several methods based on HMRF. Hidden Markov Random Fields (HMRF) constitute an elegant way to model the problem of segmentation. This modelling leads to the minimization of an energy function. In this paper we investigate direct search methods that are Nelder-Mead and Torczon methods to solve this optimization problem. The quality of segmentation is evaluated on grou…