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New technologies and devices for wireless communication networks are continually developed. In order to assess their performance, they have to be tested in realistic environments taking into account the influence of the body in wireless communications. Thus, the development of phantoms, which are synthetic materials that can emulate accurately the electromagnetic behaviour of different tissues, is...
The aim of this work is consider the application of the uncertainty method for error calculation in modern automatic network analyzers based on the multi-port correlator. The expressions for uncertainty estimates of the both types A and B are discussed. The expressions for error matrices estimators defining the MPC calibration and measuring accuracy are obtained. It is shown that this method can be...
Uncertainty in measurement of point correspondences negatively affects the accuracy and precision in the calibration of head-mounted displays (HMD). In general, the distribution of alignment errors for optical see-through calibration are not isotropic, and one can estimate its distribution based on interaction requirements of a given calibration process and the user's measurable head motion and hand-eye...
This paper describes the accurate the conventional methods for the determination of power quality parameters. The methods and procedures described apply to the measurement of harmonics, flicker, fluctuating harmonics, and interharmonics and allow uncertainties of some parts per million to be attained. The describes methods are compared with a new one proposed by authors, which is based on the effective...
The operational dynamics arising out of the diffusion of solar lamps (a new product) in rural India has been discussed in this paper. Empirical evidence is provided to show that the shortage of product supply adversely affects the diffusion process. The shortage not only delays the diffusion process, but also creates multiple phases of diffusion wherein each phase exhibits distinct new product diffusion...
As with anything new, especially metrology tools, you want to know how good the new tool is. This is generally done through comparisons with existing systems. In this paper, such a comparison is described. The new NIST method of processing measurements and uncertainties, the Microwave Uncertainty Framework will be compared to the established NIST method for measuring one and two-port scattering-parameters...
The vast majority of stochastic simulation models are imperfect in that they fail to fully emulate the entirety of real dynamics. Despite this, these imperfect models are still useful in practice, so long as one knows how the model is inexact. This inexactness is measured by a discrepancy between the proposed stochastic model and a true stochastic distribution across multiple values of some decision...
We study the empirical likelihood method in constructing statistically accurate confidence bounds for stochastic simulation under nonparametric input uncertainty. The approach is based on positing a pair of distributionally robust optimization, with a suitably averaged divergence constraint over the uncertain input distributions, and calibrated with a χ2-quantile to provide asymptotic coverage guarantees...
An effective operation of data measuring systems is not possible without the timely metrological calibration of measuring channels. Uncertainty of information imparted by uncalibrated channels leads to ineffective monitoring and wrong performance decision making. The reviews on advanced researches in the field of measuring channels calibration show negligible exploratory activity in the field and...
In this paper, we describe the implementation of building energy performance assessment system to evaluate the energy performance of existing building for energy efficiency improvement by building remodeling. In consideration of the performance effect of building structure and operation, we created a stochastic building energy model based on ISO13790 and EN15232 building energy model. In order to...
Long-term generation investment (LTGI) models have been widely used as a decision-making tool of design of energy policy. Adequate LTGI models with detailed modelling of operations are often computationally intensive. Uncertainty involved in these models poses a great challenge to the uncertainty quantification in power system reliability. This paper presents a Bayesian framework for addressing this...
Existing Simultaneous Localization and Mapping systems require an extensive manual pre-calibration process. Non-manual calibration procedures use manipulators to create known patterns in order to estimate the unknown calibration. Calibration is often time-consuming and involves humans performing repetitive tasks such as aligning a known calibration target at different poses with respect to the sensor...
Alleviating sensor location error is essential for promoting the quality of various location based services. Compared with the existing approaches which utilize the calibrators with known locations, e.g., GPS, this paper investigates the calibration performance which uses only the measurements from sources in unknown locations. Since no reference information is involved, it is revealed in this paper...
The SSDL (Secondary Standard Dosimetry Laboratory) at the LAEC (Lebanese Atomic Energy Commission) has different calibration methods for various types of dosimeters used in industrial, military and medical fields. The calibration is performed using different beams of X- rays (low and medium energy) and Gamma radiation delivered by a Cesium 137 source. The SSDL laboratory in charge of calibration services...
In foot-mounted positioning systems, it is hard to align multi-agent trajectories. In addition, the positioning accuracy is hard to maintain due to inertial drifts. An approach for trajectory initialization and calibration using iBeacons is proposed in this paper. This approach is under the framework of a particle filter. In the observation model of the particle filter, a nonparametric Gaussian Process...
We investigate the role of measurement uncertainty in achieving first-pass design success at microwave frequencies. We develop a model for state-of-the-art 250 nm heterojunction bipolar transistors, and demonstrate the propagation of correlated measurement uncertainties through the model-extraction and verification process. We then investigate the accuracy of the extracted model parameters and the...
A vibrometer is used for hydrophone calibration in conjunction with ultrasonic nonlinear pulse excitation. This enables the characterization of the amplitude and phase response of the hydrophone in a time-efficient way. The vibrometer uses one photodiode with a certain frequency characteristic. A simulation was carried out to calculate the influence of the photodiode frequency response on the measured...
ISO 376:2011 prescribes two ways of evaluating creep uncertainty in calibrations of force proving instruments: (a) one is to evaluate it from the relative creep error and (b) the other from the reversibility error. The reversibility error is a function of calibration forces, while the creep error is one single value and is not depend on the calibration forces, because the creep test is performed only...
The paper deals with issues involved in calibration of glossmeters used to the measurement of high gloss for measurement geometries 20°/20°, 60°/60°, 85°/85°. An algorithm for the adjustment and calibration at adjustment point has been described. Calibration uncertainty has been analyzed. The basic sources of uncertainty are characterized and estimated. Measurement model, the equation of measurement...
The Soil and Water Assessment Tool (SWAT) is a freely accessible hydrological modeling tool designed to simulate the impact of land-cover changes on hydrological processes over a continuous period. To test its performance in tropical climate conditions, the hydrological processes of the upper Muar watershed (UMW), Malaysia was modeled for land cover data in the year 1984. The SWAT model was run using...
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