PURPOSE To assess the impact of refractive surgery on quality of life using the National Eye Institute Refractive Error Quality of Life instrument (NEI-RQL) and to evaluate the responsiveness of our Portuguese version of the NEI-RQL instrument to surgical correction of refractive error. METHODS In this prospective study, the NEI-RQL, a 42-item questionnaire with 13 scales, was self-administer...

A microcomputer-controlled measuring instrument for phase angle measurement in low frequency range is described. It is based on the digital measurement of the time shift between input signals. To avoid the necessity of calculation of the measured phase shift, measurement of the time shift is repeated during a constant time interval to get the average value of the phase shift independent on the ...

International scientific standards organizations created standards on evaluating uncertainty in the early 1990s. Although scientists from many fields use these standards, they are not consistently implemented in the remote sensing community, where traditional error analysis framework persists. For a satellite instrument under development, this can create confusion in showing whether requirement...

A Micro Inertial Measurement unit (μIMU) which is based on Micro-Electro-Mechanical Systems (MEMS) accelerometers and gyroscope sensors is developed for real-time recognition of human hand motion. By using appropriate filtering, transformation and sensor fusion algorithms, a ubiquitous digital writing instrument is produced for recording handwriting on any surface. In this paper, we propose a m...

The problem of characterising the accuracy of, and disturbance caused by a joint measurement of position and momentum is investigated. In a previous paper the problem was discussed in the context of the unbiased measurements considered by Arthurs and Kelly. It is now shown, that suitably modified versions of these results hold for a much larger class of simultaneous measurements. The approach i...

The monitoring capability of a polarized instrument (POLDER) under high aerosol loading conditions over China is investigated. The aerosol optical thickness (AOT), which infers the aerosol burden, is used to measure the satellite monitoring capabilities. AOT products retrieved from POLDER on low aerosol loading days, and products from a radiometric instrument (MODIS) on high and low aerosol loa...

n 1939, the Taylor Instrument CompaI nies introduced a completely redesigned version of its “Fulscope” pneumatic controller: this new instrument provided, in addition to proportional and reset control actions, an action which the Taylor Instrument Companies called “pre-act.” In the same year the Foxboro Instrument Company added “Hyper-reset’’ to the proportional and reset control actions provid...

• Processes evaluated included the instrument set up (daily quality control, compensation), reagent, and sample preparation was performed. Total opportunities for error in the workflow were identified (defined as steps involving manual efforts of pipetting and labelling tubes) and manual labour time was then used to estimate indirect costs. NOTE: evaluation of error prone steps did not include ...

This paper aims at validating the efficiency of a fault injection approach to predict error rate on applications devoted to operate in radiation environment. Soft error injection experiments and radiation ground testing were performed on software modules using a digital board built on a digital signal processor which is included in a satellite instrument. The analysis of experimental results pu...

1.Differentiate accuracy and Uncertainty with example. Accuracy-Closeness to the true value. Example: Measuring accuracy is ± 0.02mm for diameter 25mm. Here the measurement true values lie between 24.98 to25.02 mm Uncertanity about the true value = ± 0.02mm 2. Differentiate between precision and accuracy. Accuracy-The maximum amount by which the result differ from true value. Precision-Degree o...