flowers in the fall. What is its common name? How do some people use it? http :// (1 of 4) [9/23/ AM]. Courtesy of When I think of autumn, apple cider often comes to mind. What is the difference. Open link in new window · Autumn Internet Hunt – cohora/ext/ Explores the season. Open link in new window · Computer Hunt 2.
|Published (Last):||20 April 2013|
|PDF File Size:||11.45 Mb|
|ePub File Size:||9.59 Mb|
|Price:||Free* [*Free Regsitration Required]|
Precision and accuracy in radiotherapy. The required precision due to random errors in the delivery of fractionated dose regime is considered. It is further suggested that random and systematic errors should not be combined with equal weight to yield an overall target uncertainty in dose delivery, systematic errors being of greater significance.
The authors conclude that imprecise dose delivery and inaccurate dose delivery affect patient-cure results differently. Accuracy and precision in thermoluminescence dosimetry.
The question of accuracy and precision in thermoluminescent dosimetry, particularly in relation to lithium fluoride phosphor, is discussed. The more important sources of error, including those due to the detectors, the reader, annealing and dosemeter design, are identified and methods of reducing their effects on accuracy and precision to a minimum are given.
Finally, the accuracy and precision achievable for three quite different applications are discussed, namely, for personal dosimetry, environmental monitoring and for the measurement of photon dose distributions in phantoms. A Note on ” Accuracy ” and ” Precision “. Advocates the use of precision ” rather than accuracy ” in defining reliability. These terms are consistently differentiated in certain sciences. Review of psychological and measurement literature reveals, however, interchangeable usage of the terms in defining reliability.
Accuracy and precision in activation analysis: Accuracy and precision in activation analysis was investigated with regard to counting of induced radioactivity. The various parameters discussed include configuration, positioning, density, homogeneity, intensity, radioisotopic purity, peak integration, and nuclear constants.
Experimental results are presented for many of these parameters. The results obtained indicate that counting errors often contribute significantly to the inaccuracy and aur of analyses. The magnitude of these errors range from less than 1 percent to cihora percent or more in many cases. Ultra-wideband ranging precision and accuracy. This paper provides an overview of ultra-wideband UWB in the context of ranging applications and assesses the precision and accuracy of UWB ranging from both a theoretical perspective and a practical perspective using real data.
The paper begins with a brief history cohira UWB technology and the most current definition of what constitutes an UWB signal. UWB ranging methods are described and potential error sources are discussed.
Two types of commercially available UWB ranging radios are introduced which are used in testing. Actual ranging accuracy is assessed from line-of-sight testing under benign signal conditions by comparison to high- accuracy electronic distance measurements and to ranges derived from GPS real-time kinematic positioning. Range measurements obtained in outdoor testing with line-of-sight obstructions and strong reflection sources ait compared to ranges derived from classically surveyed positions. The paper concludes with a discussion of the potential applications for UWB ranging.
This is a technical report discussing our current level of understanding of a wide and varying distribution of uncertainties in velocity results from Photonic Doppler Velocimetry in its application to gas gun experiments. Using propagation of errors methods with statistical averaging of photon number fluctuation in the detected photocurrent and subsequent addition of electronic recording noise, we learn that the velocity uncertainty in VISAR can be written in closed form.
For PDV, the non-linear frequency transform and peak fitting methods employed make propagation of errors estimates notoriously wxt difficult to write down cobora closed form expect in the limit of constant velocity and low time resolution large analysis-window width.
An alternative method of error propagation in PDV is to use Monte Carlo methods with a simulation of the time domain signal based on results from the spectral domain. A key problem for Monte Carlo estimation for an experiment is a correct estimate of that portion of the time-domain noise associated with the peak-fitting region-of-interesting in the spectral domain. Using short-time Fourier transformation spectral analysis xet working with the phase dependent real and imaginary parts allows removal of amplitude-noise cross terms that invariably show up when working with correlation-based methods or FFT power spectra.
Estimation of the noise associated with a given spectral region of interest is then possible. At this level of progress, we learn that Monte Carlo trials with random recording noise and initial uncontrolled phase yields velocity uncertainties that are not as large as those observed.
specificity accuracy precision: Topics by
In a search for additional noise sources, a speckleinterference modulation contribution with off axis rays was investigated, and was found to add a velocity variation beyond that from the recording noise due to random interference between off axis raysbut in our experiments the speckle modulation precision was not as important as the. Hardware accuracy counters cohroa application precision and quality feedback.
exr Methods, devices, and systems for capturing an accuracy of an instruction executing on a processor. An instruction may be executed on the processor, and the accuracy cohoa the instruction may be captured using a hardware counter circuit. The accuracy of the instruction may be captured by analyzing bits of at least one value of the instruction to determine a minimum or maximum precision datatype for representing the field, and determining whether to adjust a value of the hardware counter circuit accordingly.
The representation may be output to a debugger or logfile for use by a developer, or may be output to a runtime or virtual machine to automatically adjust instruction precision or gating of portions of the processor datapath. Accuracyprecisionand lower detection limits a deficit reduction approach.
The evaluation of the accuracyprecision and lower detection wut of the determination of trace radionuclides in environmental samples can become quite sophisticated and time consuming. This in turn could add significant cost to the analyses being performed.
In the present method, a open-quotes deficit reduction approachclose quotes has been taken to keep costs low, but at the same time provide defensible data. In order to measure the accuracy of a particular method, reference samples are measured over the time period that the actual samples are being analyzed. Using a Lotus spreadsheet, data are compiled and an average accuracy is computed.
If pairs of reference samples are analyzed, then precision can also be evaluated from the duplicate data sets. The standard deviation can be calculated if the reference concentrations of the duplicates are all in the same general range. Laboratory blanks are used to estimate the lower detection limits. The lower detection limit is calculated as 4. A Lotus spreadsheet is again used to compile data and LDLs aur different periods of time can be compared. Using dichotomous samplers in Durham, NC, we collected aerosol samples on Teflon filters in two size ranges.
A regression line was calculated implicitly assuming errors in both measurements of mass. Accuracy and precision in the calculation of phenology metrics.
We show that precision is a greater concern than accuracy for many of these cohorx, an important point that has been hereto overlooked in the literature. The variability in precision between Furthermore, there are important differences in the inherent variability of the metrics that may be crucial in the interpretation of studies based upon them. Phytoplankton phenology the timing of seasonal events is cohoora commonly used indicator for evaluating responses of marine ecosystems to climate change.
However, phenological metrics are vulnerable to observation- bloom amplitude, missing data, and observational noise and analysis-related temporal Structured light systems are popular in part because they can be constructed from off-the-shelf low cost components. In this paper we quantitatively show how common design parameters affect precision and accuracy in such systems, supplying a much needed guide for practitioners.
Experiments are performed on our own structured light setup, consisting of two cameras and a projector. We place our focus on the influence of calibration design parameters, the calibration procedure and encoding strategy and present our findings. Finally, we compare our setup to a state of the art aug grade commercial scanner. Our results show that comparable, and in some cases better, results can be obtained using the parameter settings determined in this study.
Assessment of Sr in water samples: The study of artificial radionuclides dispersion into the environment is very important to control the nuclear waste discharges, nuclear accidents and nuclear weapons testing. The accidents in Fukushima Daiichi Nuclear Power Plant and Chernobyl Nuclear Power Plant, released several radionuclides in the environment by aerial deposition and liquid discharge, with various level of radioactivity.
Cerenkov, LSC direct method and with radiochemical separation. The performance of the methodologies was evaluated by using two scintillation counters Quantulus and Hidex. The 90 Sr was one of the elements released into the environment. The 90 Sr is produced by nuclear fission with a physical half-life of The aims of this study are to evaluate the precision and accuracy of three methodologies for the determination of 90 Sr in water samples: Aspects of precision and accuracy in neutron activation analysis.
Analytical results without systematic errors and with accurately known random errors are normally distributed around their true values. Such results may be produced by means of neutron activation analysis both with and without radiochemical separation. When all sources of random variation are known a priori, their effect may be combined with the Poisson statistics characteristic of the counting process, and the standard deviation of a single analytical result may be estimated.
The various steps of a complete neutron activation analytical procedure are therefore studied in detail with respect to determining their contribution to the overall choora of the final result.
Verification of the estimated standard deviation is carried out by demonstrating the absence of significant unknown random errors through analysing, ezt replicate, samples covering the range of concentrations and matrices anticipated in actual use.
Agreement between the estimated and the observed variability of replicate results is ezt tested by a simple statistic T based on the chi-square distribution. It is found that results from neutron activation analysis on biological samples can be brought into statistical control.
In routine application of methods in statistical control the same statistical test may be used for quality control when some of the actual samples are analysed in duplicate.
This analysis of precision serves to detect unknown or unexpected sources of variation of the analytical results, and both random and systematic errors have been discovered in practical trace element investigations in different areas of research.
Particularly, at the ultratrace level of concentration where there are few or no standard reference materials for ascertaining the xut of results, the proposed quality control based on the analysis of precision combined with neutron activation analysis with radiochemical separation, with an a priori precision independent of the level of concentration, becomes a.
Precision and accuracy of mechanistic-empirical pavement design. Full Text Available are discussed in general. The effects of variability at error on the design accuracy and design cohroa are lastly illustrated at the cohroa of a simple mechanistic-empirical design problem, showing that the engineering models alone determine the accuracy Accuracy and precision of four common peripheral temperature measurement methods in intensive care patients.
An accurate determination of body temperature in critically ill patients is cohors fundamental requirement for initiating the proper process of diagnosis, and also therapeutic actions; therefore, the aim of the study was to assess the accuracy and precision of four noninvasive peripheral methods of temperature measurement compared to the central nasopharyngeal measurement.
In this observational prospective study, patients were recruited from the intensive care unit of Imam Ali Hospital of Kermanshah. The rxt body temperatures were measured by four peripheral methods; oral, axillary, tympanic, and forehead along with a standard central nasopharyngeal measurement. After data collection, the results were analyzed by paired t-test, kappa coefficient, receiver operating characteristic curve, and using Statistical Package for the Social Sciences, version 19, software.
Sensitivity and specificity of both the left and right tympanic membranes were more than for other methods. The tympanic and forehead methods had the cohira and lowest accuracy for measuring body temperature, respectively.
It is recommended to use the tympanic method right and left for assessing a patient’s body temperature in the intensive care units because of high accuracy and acceptable precision. Accuracy and precision of oscillometric blood pressure in standing conscious horses. To evaluate the accuracy and precision of systolic arterial pressure SAPdiastolic arterial pressure DAPand mean arterial pressure MAP in conscious horses obtained with an oscillometric NIBP device when compared to invasively measured Agreement analysis with replicate measures was utilized to calculate bias accuracy and standard deviation SD of bias precision.
We show that high energy measurements of Drell-Yan at the LHC can serve qut electroweak precision tests.