Search results for "Measurement"
showing 10 items of 2918 documents
Temperature measurement in gas mixtures by femtosecond Raman-induced polarization spectroscopy
2003
European Conference on Nonlinear Optical Spectroscopy (ECONOS) MAR 30-APR 01, 2003 BESANCON, FRANCE; The potential of femtosecond Raman-induced polarization spectroscopy (RIPS) for the simultaneous determination of temperature and concentrations was investigated. These measurements were related to the rotational time response of the molecular gas mixture, which was measured as a function of the pump-probe time delay. The change of the polarizability anisotropy with respect to the vibrational levels was taken into account. The results of temperature measurements in pure CO2 showed good agreement with the values obtained by a thermocouple. The RIPS technique was also applied to a CO2-N2 gas m…
Optical Monitoring of Microplastics Filtrated from Wastewater Sludge and Suspended in Ethanol.
2021
The abundance of microplastics (MPs) in the atmosphere, on land, and especially in water bodies is well acknowledged. In this study, we establish an optical method based on three different techniques, namely, specular reflection to probe the medium, transmission spectroscopy measurements for the detection and identification, and a speckle pattern for monitoring the sedimentation of MPs filtrated from wastewater sludge and suspended in ethanol. We used first Raman measurements to estimate the presence and types of different MPs in wastewater sludge samples. We also used microscopy to identify the shapes of the main MPs. This allowed us to create a teaching set of samples to be characterized …
Cross validation of hard-copy and web-based formats of the Sport Imagery Ability Measure
2018
The purpose of this multi-sample study was to examine the psychometric characteristics, factor structure, and measurement invariance of the hard-copy and web-based versions of a measure of sport imagery ability, termed Sport Imagery Ability Measure (SIAM). In the first sample, Spanish athletes (N = 274, 161 men, 113 women, Mage = 21.91, SD = 6.67) completed a hard-copy version of the SIAM. A newly developed web-based version of the SIAM was cross validated in an independent group (N = 266, 147 men, 119 women, Mage = 25.93, SD = 9.84). A small group of participants (n = 16) completed both versions. Exploratory structural equation modelling and confirmatory factor analysis of the data from th…
Joint Subcarrier and Phase Shifts Optimization for RIS-aided Localization-Communication System
2022
Joint localization and communication systems have drawn significant attention due to their high resource utilization. In this paper, we consider a reconfigurable intelligent surface (RIS)-aided simultaneously localization and communication system. We first determine the sum squared position error bound (SPEB) as the localization accuracy metric for the presented localization-communication system. Then, a joint RIS discrete phase shifts design and subcarrier assignment problem is formulated to minimize the SPEB while guaranteeing each user’s achievable data rate requirement. For the presented non-convex mixed-integer problem, we propose an iterative algorithm to obtain a suboptimal solution …
Thermoelectric radiation detector based on a superconductor-ferromagnet junction : Calorimetric regime
2018
We study the use of a thermoelectric junction as a thermal radiation detector in the calorimetric regime, where single radiation bursts can be separated in time domain. We focus especially on the case of a large thermoelectric figure of merit ZT affecting significantly, for example, the relevant thermal time scales. This work is motivated by the use of hybrid superconductor/ferromagnet systems in creating an unprecedentedly high low-temperature ZT even exceeding unity. Besides constructing a very general noise model which takes into account cross correlations between charge and heat noise, we show how the detector signal can be efficiently multiplexed by the use of resonant LC circuits givi…
Challenges to the development of energy performance measurement : a systems thinking approach
2016
Growing global energy consumption and its consequent hindrance to sus-tainable development poses one of the greatest challenges of today. Impro-vement of the end-use energy efficiency is commonly regarded as one of the most basic and significant countermeasures for curbing the rising energy needs. However, it seems that the progress of end-use energy management is currently hindered due to the complexities involved in the measurement and management of energy efficiency. In essence, the lack of appropriate energy performance metrics constitute a gap between the current organizational needs and scientific literature. Furthermore, the current scientific debate has questioned whether ener-gy ef…
Quality-control procedure for dry-process rubberised asphalt mastics
2019
Crumb Rubber (CR) can be incorporated into asphalt mixes via the dry process by directly adding CR into the mixer together with other asphalt mixture’s components, or with the wet process where the CR is used as a bitumen modifier. While the wet process allows an accurate monitoring of the interaction between CR and bitumen, the lack of control represents a main issue in the dry process. In fact, in the latter the CR particles keep swelling during hauling and possibly also after paving operations, often causing workability issues and premature failures. This study wants to provide a methodology that could help quality control procedures of bitumen/filler/rubber systems during mixing, haulin…
Contributions of mean and shape of blood pressure distribution to worldwide trends and variations in raised blood pressure: A pooled analysis of 1018…
2018
Background: Change in the prevalence of raised blood pressure could be due to both shifts in the entire distribution of blood pressure (representing the combined effects of public health interventions and secular trends) and changes in its high-blood-pressure tail (representing successful clinical interventions to control blood pressure in the hypertensive population). Our aim was to quantify the contributions of these two phenomena to the worldwide trends in the prevalence of raised blood pressure. Methods: We pooled 1018 population-based studies with blood pressure measurements on 88.6 million participants from 1985 to 2016. We first calculated mean systolic blood pressure (SBP), mean dia…
How many longitudinal covariate measurements are needed for risk prediction?
2014
Abstract Objective In epidemiologic follow-up studies, many key covariates, such as smoking, use of medication, blood pressure, and cholesterol, are time varying. Because of practical and financial limitations, time-varying covariates cannot be measured continuously, but only at certain prespecified time points. We study how the number of these longitudinal measurements can be chosen cost-efficiently by evaluating the usefulness of the measurements for risk prediction. Study Design and Setting The usefulness is addressed by measuring the improvement in model discrimination between models using different amounts of longitudinal information. We use simulated follow-up data and the data from t…
Quality Management in Service Desk : How Does Service Desk Managers Define and Measure Quality
2018
Many public and private sector organisations are depending on IT services provided by external service providers. The quality of the service affects the customer satisfaction and consequently the customer behaviour. The concept of quality has many meanings in the literature. In this paper, we study how service desk managers perceive the concept of quality and how to manage it in an organisation which has adopted ITIL. Our findings indicate that the quality is seen only in terms of how the agreed service levels are achieved. This view excludes the quality of the processes used to deliver IT services. Quality measurements are reflecting the perception of the concept of quality. peerReviewed