Spatial Sampling in Monostatic Subsurface Radar Imaging

10.36227/techrxiv.12690155 ◽

2020 ◽

Author(s):

Maria Antonia Maisto ◽

Rocco Pierri ◽

Raffaele Solimene

Keyword(s):

Sampling Strategy ◽

Data Sampling ◽

Subsurface Scattering ◽

Point Spread Functions ◽

Point Spread ◽

Measurement Domain ◽

Standard Sampling ◽

The One ◽

Space Case

<div>This paper deals with microwave subsurface imaging obtained by a migration-like inversion scheme, for a 2D monostatic scalar configuration and a two-layered background medium. The focus is on the determination of a data sampling strategy which allows to reduce the number of required measurements and at the same time keep the same performance in the reconstructions. To this end, the measurement points are determined in order to approximate the point-spread function corresponding to the ideal continuous case (i.e., the case in which the data space is not sampled at all). Basically, thanks to suitable variable transformations the point-spread functions is recast as a Fourier-like operator and this provides insight to devise the sampling scheme. It is shown that resulting measurement spatial positions are non-uniformly arranged across the measurement domain and their number can be much lower than the one provided by some literature standard sampling criteria. The study also contains a comparison with the free space case so as to highlight the role played by the half-space that schematized the subsurface scattering scenario on the number and the locations of the measurement points. Numerical examples are also included to check the theoretical arguments.</div>

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Solar radiation focusing: analysis and determination of reflecting facets point spread functions and alignment errors

Journal of Optics ◽

10.1088/0150-536x/20/5/005 ◽

1989 ◽

Vol 20 (5) ◽

pp. 225-240 ◽

Cited By ~ 4

Author(s):

F Henault ◽

C Royere

Keyword(s):

Solar Radiation ◽

Point Spread Functions ◽

Radiation Focusing ◽

Point Spread ◽

Alignment Errors

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An on Orbit Determination of Point Spread Functions for the Interface Region Imaging Spectrograph

Solar Physics ◽

10.1007/s11207-018-1347-9 ◽

2018 ◽

Vol 293 (9) ◽

Cited By ~ 6

Author(s):

Hans Courrier ◽

Charles Kankelborg ◽

Bart De Pontieu ◽

Jean-Pierre Wülser

Keyword(s):

Orbit Determination ◽

Interface Region ◽

Point Spread Functions ◽

Point Spread ◽

Imaging Spectrograph

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High Precision Crowded Field Photometry

Highlights of Astronomy ◽

10.1017/s1539299600008613 ◽

1989 ◽

Vol 8 ◽

pp. 651-656

Author(s):

Peter Linde

Keyword(s):

High Precision ◽

List Type ◽

Point Spread Functions ◽

Error Sources ◽

Point Spread ◽

Spread Function ◽

Star Group ◽

Local Background ◽

Definition Of

AbstractMethods have been developed for high precision photometry in crowded stellar fields. The procedure includes the following steps:• Determination of a two-dimensional point spread function• Definition of groups of stars with mutually overlapping images• Determination of local background for each star group• Simultaneous fitting of point spread functions, one for each star in the groupThe Lund approach emphasizes interactivity. Many fundamental procedures are facilitated by the use of an optimised image display. Extensive modelling has been done to study the influence of various error sources.

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Determination of the ScaRaB FM1 broadband channel point spread functions

IEEE Transactions on Geoscience and Remote Sensing ◽

10.1109/36.774711 ◽

1999 ◽

Vol 37 (4) ◽

pp. 2004-2010 ◽

Cited By ~ 2

Author(s):

S. Dewitte ◽

P. Boekaerts ◽

F. Sirou

Keyword(s):

Point Spread Functions ◽

Point Spread

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Guidelines for calibration in analytical chemistry. Part 2: Multicomponent calibration (IUPAC Technical Report)

Pure and Applied Chemistry ◽

10.1351/pac200476061215 ◽

2004 ◽

Vol 76 (6) ◽

pp. 1215-1225 ◽

Cited By ~ 33

Author(s):

Klaus Danzer ◽

M. Otto ◽

L. A. Currie

Keyword(s):

Analytical Chemistry ◽

Chemical Species ◽

Test Sample ◽

Ideal Case ◽

Technical Report ◽

Measurement Domain ◽

The One ◽

Analytical Practice ◽

The Ideal

Calibration in analytical chemistry refers to the relation between sample domain and measurement domain (signal domain) expressed by an analytical function x = fs(Q) representing a pattern of chemical species Q and their amounts or concentrations x in a given test sample on the one hand and a measured function y = f(z) that may be a spectrum, chromatogram, etc. Simultaneous multispecies analyses are carried out mainly by spectroscopic and chromatographic methods in a more or less selective way. For the determination of n species Qi (i = 1,2 …n), at least n signals must be measured which should be well separated in the ideal case. In analytical practice, the situation can be different.

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Two-Stage Procedure for the Quantitative Determination of Autoprothrombin III Concentration and Some Applications

Thrombosis and Haemostasis ◽

10.1055/s-0038-1655029 ◽

1967 ◽

Vol 18 (01/02) ◽

pp. 198-210 ◽

Cited By ~ 5

Author(s):

Ronald S Reno ◽

Walter H Seegers

Keyword(s):

Prothrombin Time ◽

Factor Vii ◽

Two Stage ◽

Pronounced Increase ◽

One Stage ◽

Assay Procedure ◽

Bovine Plasma ◽

The One ◽

Autoprothrombin C

SummaryA two-stage assay procedure was developed for the determination of the autoprothrombin C titre which can be developed from prothrombin or autoprothrombin III containing solutions. The proenzyme is activated by Russell’s viper venom and the autoprothrombin C activity that appears is measured by its ability to shorten the partial thromboplastin time of bovine plasma.Using the assay, the autoprothrombin C titre was determined in the plasma of several species, as well as the percentage of it remaining in the serum from blood clotted in glass test tubes. Much autoprothrombin III remains in human serum. With sufficient thromboplastin it was completely utilized. Plasma from selected patients with coagulation disorders was assayed and only Stuart plasma was abnormal. In so-called factor VII, IX, and P.T.A. deficiency the autoprothrombin C titre and thrombin titre that could be developed was normal. In one case (prethrombin irregularity) practically no thrombin titre developed but the amount of autoprothrombin C which generated was in the normal range.Dogs were treated with Dicumarol and the autoprothrombin C titre that could be developed from their plasmas decreased until only traces could be detected. This coincided with a lowering of the thrombin titre that could be developed and a prolongation of the one-stage prothrombin time. While the Dicumarol was acting, the dogs were given an infusion of purified bovine prothrombin and the levels of autoprothrombin C, thrombin and one-stage prothrombin time were followed for several hours. The tests became normal immediately after the infusion and then went back to preinfusion levels over a period of 24 hrs.In other dogs the effect of Dicumarol was reversed by giving vitamin K1 intravenously. The effect of the vitamin was noticed as early as 20 min after administration.In response to vitamin K the most pronounced increase was with that portion of the prothrombin molecule which yields thrombin. The proportion of that protein with respect to the precursor of autoprothrombin C increased during the first hour and then started to go down and after 3 hrs was equal to the proportion normally found in plasma.

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SIMPLIFIED DEXAMETHASONE SUPPRESSION TEST

Acta Endocrinologica ◽

10.1530/acta.0.0610219 ◽

1969 ◽

Vol 61 (2) ◽

pp. 219-231 ◽

Cited By ~ 14

Author(s):

V. H. Asfeldt

Keyword(s):

Cushing’S Syndrome ◽

Normal Subjects ◽

Cushing's Syndrome ◽

Dexamethasone Suppression Test ◽

Clinical Value ◽

Suppression Test ◽

The One ◽

Steroid Excretion ◽

Dexamethasone Suppression

ABSTRACT This is an investigation of the practical clinical value of the one mg dexamethasone suppression test of Nugent et al. (1963). The results, evaluated from the decrease in fluorimetrically determined plasma corticosteroids in normal subjects, as well as in cases of exogenous obesity, hirsutism and in Cushing's syndrome, confirm the findings reported in previous studies. Plasma corticosteroid reduction after one mg of dexamethasone in cases of stable diabetes was not significantly different from that observed in control subjects, but in one third of the insulin-treated diabetics only a partial response was observed, indicating a slight hypercorticism in these patients. An insufficient decrease in plasma corticosteroids was observed in certain other conditions (anorexia nervosa, pituitary adenoma, patients receiving contraceptive or anticonvulsive treatment) with no hypercorticism. The physiological significance of these findings is discussed. It is concluded that the test, together with a determination of the basal urinary 17-ketogenic steroid excretion, is suitable as the first diagnostic test in patients in whom Cushing's syndrome is suspected. In cases of insufficient suppression of plasma corticosteroids, further studies, including the suppression test of Liddle (1960), must be carried out.

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A Validated 2D-LC-UV Method for Simultaneous Determination of Imatinib and N-demethylimatinib in Plasma and Its Clinical Application for Therapeutic Drug Monitoring with GIST Patients

Current Pharmaceutical Analysis ◽

10.2174/1573412917999201124143834 ◽

2020 ◽

Vol 17 ◽

Author(s):

Houli Li ◽

Di Zhang ◽

Xiaoliang Cheng ◽

Qiaowei Zheng ◽

Kai Cheng ◽

...

Keyword(s):

Therapeutic Drug Monitoring ◽

One Dimension ◽

Therapeutic Drug ◽

Plasma Samples ◽

Column Temperature ◽

Injection Volume ◽

Target Analytes ◽

The One ◽

Middle Column

Background: The trough concentration (Cmin) of Imatinib (IM) is closely related to the treatment outcomes and adverse reactions of patients with gastrointestinal stromal tumors (GIST). However, the drug plasma level has great interand intra-individual variability, and therapeutic drug monitoring (TDM) is highly recommended. Objective: To develop a novel, simple, and economical two-dimensional liquid chromatography method with ultraviolet detector (2D-LC-UV) for simultaneous determination of IM and its major active metabolite, N-demethyl imatinib (NDIM) in human plasma, and then apply the method for TDM of the drug. Method: Sample was processed by simple protein precipitation. Two target analytes were separated on the one-dimension column, captured on the middle column, and then transferred to the two-dimension column for further analysis. The detection was performed at 264 nm. The column temperature was maintained at 40˚C and the injection volume was 500 μL. Totally 32 plasma samples were obtained from patients with GIST who were receiving IM. Method: Sample was processed by simple protein precipitation. Two target analytes were separated on the one-dimension column, captured on the middle column, and then transferred to the two-dimension column for further analysis. The detection was performed at 264 nm. The column temperature was maintained at 40˚C and the injection volume was 500 μL. Totally 32 plasma samples were obtained from patients with GIST who were receiving IM. Conclusion: The novel 2D-LC-UV method is simple, stable, highly automated and independent of specialized technicians, which greatly increases the real-time capability of routine TDM for IM in hospital.

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