نتایج جستجو برای: correction factors
تعداد نتایج: 1233116 فیلتر نتایج به سال:
The least trimmed squares estimator and the minimum covariance determinant estimator [5] are frequently used robust estimators of regression and of location and scatter. Consistency factors can be computed for both methods to make the estimators consistent at the normal model. However, for small data sets these factors do not make the estimator unbiased. Based on simulation studies we therefore...
This work is part of the multi-center Alzheimer's Disease Neuroimaging Initiative (ADNI), a large multi-site study of dementia, including patients having mild cognitive impairment (MCI), probable Alzheimer's disease (AD), as well as healthy elderly controls. A major portion of ADNI involves the use of [(18)F]-fluorodeoxyglucose (FDG) with positron emission tomography (PET). The objective of thi...
to make an accurate estimation of the uptake of radioactivity in an organ using the conjugate view method, corrections of physical factors, such as background activity, scatter, and attenuation are needed. the aim of this study was to evaluate the accuracy of four different methods for background correction in activity quantification of the heart in myocardial perfusion scans. the organ activit...
Data required for the determination of the absolute air kerma rate for (60)Co and (137)Cs gamma-rays using spherical cavity chambers were calculated using the EGS4 Monte Carlo system. Mass energy-absorption coefficient ratio and the stopping power ratio were calculated for a 10 cm(3) primary standard graphite-walled ionization chamber from the unfolded energy pulse height distributions of (60)C...
Quantitation in cardiac positron emission tomography (PET) and single-photon emission computed tomography (SPECT) depends on being able to correct for several physical factors that tend to distort the data. One of the most important of these corrections is the correction for attenuation. For PET, cardiac attenuation correction is a reality, although certain problems remain to be solved. For SPE...
The literature on inducers in epilepsy and bipolar disorder is seriously contaminated by false negative findings. This is part i of a comprehensive review on antiepileptic drug (AED) inducers using both mechanistic pharmacological and evidence-based medicine to provide practical recommendations to neurologists and psychiatrists concerning how to control for them. Carbamazepine, phenobarbital an...
This paper looks at the development and implementation of the additional secondary phase factor (ASF) real-time correction system for the Automatic Identification System (AIS) signal. A large number of test data were collected using the developed ASF correction system and the propagation characteristics of the AIS signal that transmits at sea and the ASF real-time correction algorithm of the AI...
The PILATUS detector system is widely used for X-ray experiments at third-generation synchrotrons. It is based on a hybrid technology combining a pixelated silicon sensor with a CMOS readout chip. Its single-photon-counting capability ensures precise and noise-free measurements. The counting mechanism introduces a short dead-time after each hit, which becomes significant for rates above 10(6) p...
OBJECTIVE To propose a simplified method of correcting vital information and estimating the coefficient of infant mortality in Brazil. METHODS Vital data in the information systems on mortality and live births were corrected using correction factors, estimated based on events not reported to the Brazilian Ministry of Health and obtained by active search. This simplified method for correcting ...
The available shear correction factors have mainly been developed for homogeneous isotropic plates and/or assuming that no shear tractions are imposed on the top and bottom surfaces of the plate. In the present research, a more general case of a circular functionally graded plate subjected to non-uniform normal and shear tractions at the top and bottom surfaces is considered. These non-uniform ...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید