scholarly journals Accurate Determination of Conversion Gains of SVOM VT CCDs Based on a Signal-Dependent Charge-Sharing Mechanism

Electronics ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 931
Author(s):  
Yue Pan ◽  
Xuewu Fan ◽  
Hu Wang ◽  
Hui Zhao ◽  
Yulei Qiu ◽  
...  
Keyword(s):  
Accurate Determination ◽  
Control Variable ◽  
Charge Sharing ◽  
Charge Coupled Device ◽  
Variance Method ◽  
Polynomial Curve ◽  
Curve Method ◽  
Ccd Detectors ◽  
The Relationship

The signal-variance method and the photon transfer curve method are the most valuable tools for calculating the conversion gains of charge-coupled device (CCD) detectors. This paper describes the phenomena that arise in the conversion gain measurements of space multi-band variable object monitor (SVOM) visible telescope (VT) CCDs, where the results of the signal-variance method increase with the image gray level, and the results of the photon transfer curve method appear with nonlinearity, which is caused by the signal-dependent charge sharing mechanism of back-illuminated CCDs. A numerical simulation model based on random variables was adopted to analyze the influence of the mechanism on the gain determination. The model simulates all the signals and noise in the flat field image, including the photon signal and photon-shot noise, readout noise, fixed pattern noise, and the signal-dependent charge-sharing signal, and it demonstrated agreement with the experimental data. Then, we proposed a quadratic polynomial curve-fitting formula for the photon transfer curve, and we quantitatively analyzed the relationship between the fitting coefficients and the gain, the signal-dependent charge sharing coefficient, and the full well capacity using the control variable method. Finally, the formula was used to accurately determine the conversion gains of SVOM VT CCDs.

The Relationship Between Galvanic Current and Dissolution Rates

CORROSION ◽  
1973 ◽  
Vol 29 (10) ◽  
pp. 403-405 ◽  
Author(s):  
FLORIAN MANSFELD
Keyword(s):  
Accurate Determination ◽  
Current Data ◽  
Al Alloys ◽  
Metals And Alloys ◽  
Dissimilar Metals ◽  
Dissolution Rates ◽  
Galvanic Current ◽  
Experimental Support ◽  
The Relationship

Abstract The recent development of instrumentation suitable for accurate determination of galvanic currents suggests that more data of this nature will be gathered and reported. It is shown that galvanic current data cannot be an accurate measure of dissolution rates in many cases, since dissolution rates from the galvanic current are smaller than the true dissolution rates. Correction of galvanic current data is possible, however, and correction procedures are explained for two limiting cases. Experimental support for the relationships derived is presented for Al alloys in aerated 3.5% NaCl coupled to a variety of dissimilar metals and alloys.

Microstructure Reconstruct of Continuous Fiber Bundles by Image Analysis

2011 ◽  
Vol 332-334 ◽  
pp. 1015-1018 ◽  
Author(s):  
Jin Chao Li ◽  
Li Chen ◽  
L. Li
Keyword(s):  
Spatial Configuration ◽  
Accurate Determination ◽  
Fiber Bundles ◽  
Continuous Fiber ◽  
Charge Coupled Device ◽  
3D Solid ◽  
And Behavior ◽  
Bundle Structure

The precise characterization of the microstructure of bundle is essential for an accurate determination of their properties and behavior. This paper presents a study on the microstructure of continuous fiber bundles by Serial Sectioning Method. Bundle is firstly cured by resin to keep the fiber spatial configuration in the bundle. A series of cross-section images vertical to the bundle direction are captured and polished enough to take digital photographs by the Charge-coupled Device (CCD) microscope. A 3D solid microstructure of the bundle is implemented by linking the correspondent circle for separate fiber in the 3D solid software Pro/E. Reconstructed bundle structure truly represents the spatial configuration of the fibers in the bundle.

Raman Spectroscopic Study for the Determination of Monoethanolamine Concentration

2014 ◽  
Vol 625 ◽  
pp. 709-713
Author(s):  
Mee Kee Wong ◽  
Mohd Azmi Bustam ◽  
Mohd Shariff Azmi
Keyword(s):  
Accurate Determination ◽  
Area Ratio ◽  
Coefficient Of Determination ◽  
Raman Spectroscopic ◽  
Major Interest ◽  
Progressive Growth ◽  
Raman Study ◽  
Ratio Correlation ◽  
The Relationship

Thermodynamic model is one of the important elements in designing and operating CO2removal systems, thus accurate determination of the thermodynamic properties of CO2in aqueous amine is of major interest for both technical and economical considerations. Quantitative Raman study of aqueous monoethanolamine (MEA) solutions of concentration ranging from 0 to 99 mass % in the spectral region between 300 and 3100 cm− 1was performed. Band envelopes were resolved with Gaussian Lorentzian function. Progressive growth of area under these peaks with increasing concentration was used as the parameter to construct calibration curve. Area ratio of selected peaks was plotted against MEA concentration to depict the relationship between MEA concentration and each area ratio. Correlation for A1460/A933has coefficient of determination closest to unity and lowest mean squared area. MEA concentration can be calculated from the equation derived from correlation between A1460/A933and MEA mass %.

A quantitative approach to inner shell losses

1978 ◽  
Vol 36 (1) ◽  
pp. 526-527 ◽  
Author(s):  
R.D. Leapman ◽  
P. Rez ◽  
D.F. Mayers
Keyword(s):  
Energy Transfer ◽  
Cross Section ◽  
Cross Sections ◽  
Accurate Determination ◽  
Background Intensity ◽  
Core Excitation ◽  
Quantitative Basis ◽  
Cross Section Differential ◽  
Bound Electrons

Microanalysis by EELS has been developing rapidly and though the general form of the spectrum is now understood there is a need to put the technique on a more quantitative basis (1,2). Certain aspects important for microanalysis include: (i) accurate determination of the partial cross sections, σx(α,ΔE) for core excitation when scattering lies inside collection angle a and energy range ΔE above the edge, (ii) behavior of the background intensity due to excitation of less strongly bound electrons, necessary for extrapolation beneath the signal of interest, (iii) departures from the simple hydrogenic K-edge seen in L and M losses, effecting σx and complicating microanalysis. Such problems might be approached empirically but here we describe how computation can elucidate the spectrum shape.The inelastic cross section differential with respect to energy transfer E and momentum transfer q for electrons of energy E0 and velocity v can be written as

Fast calibration of CBED patterns for quantitative analysis

1993 ◽  
Vol 51 ◽  
pp. 674-675
Author(s):  
M.A. Gribelyuk ◽  
M. Rühle
Keyword(s):  
Reciprocal Lattice ◽  
Accurate Determination ◽  
Incident Beam ◽  
Crystal Thickness ◽  
Structure Model ◽  
Beam Direction ◽  
Transmitted Beam ◽  
Reciprocal Vector ◽  
On Line

A new method is suggested for the accurate determination of the incident beam direction K, crystal thickness t and the coordinates of the basic reciprocal lattice vectors V1 and V2 (Fig. 1) of the ZOLZ plans in pixels of the digitized 2-D CBED pattern. For a given structure model and some estimated values Vest and Kest of some point O in the CBED pattern a set of line scans AkBk is chosen so that all the scans are located within CBED disks.The points on line scans AkBk are conjugate to those on A0B0 since they are shifted by the reciprocal vector gk with respect to each other. As many conjugate scans are considered as CBED disks fall into the energy filtered region of the experimental pattern. Electron intensities of the transmitted beam I0 and diffracted beams Igk for all points on conjugate scans are found as a function of crystal thickness t on the basis of the full dynamical calculation.

Computer-Assisted High-Re Solution TEM

1990 ◽  
Vol 48 (1) ◽  
pp. 162-163
Author(s):  
F.A. Ponce ◽  
H. Hikashi
Keyword(s):  
Signal To Noise Ratio ◽  
Accurate Determination ◽  
Computer Software ◽  
Video Camera ◽  
Image Contrast ◽  
Objective Lens ◽  
Computer Assisted ◽  
Optical Parameters ◽  
Astigmatism Correction

The determination of the atomic positions from HRTEM micrographs is only possible if the optical parameters are known to a certain accuracy, and reliable through-focus series are available to match the experimental images with calculated images of possible atomic models. The main limitation in interpreting images at the atomic level is the knowledge of the optical parameters such as beam alignment, astigmatism correction and defocus value. Under ordinary conditions, the uncertainty in these values is sufficiently large to prevent the accurate determination of the atomic positions. Therefore, in order to achieve the resolution power of the microscope (under 0.2nm) it is necessary to take extraordinary measures. The use of on line computers has been proposed [e.g.: 2-5] and used with certain amount of success.We have built a system that can perform operations in the range of one frame stored and analyzed per second. A schematic diagram of the system is shown in figure 1. A JEOL 4000EX microscope equipped with an external computer interface is directly linked to a SUN-3 computer. All electrical parameters in the microscope can be changed via this interface by the use of a set of commands. The image is received from a video camera. A commercial image processor improves the signal-to-noise ratio by recursively averaging with a time constant, usually set at 0.25 sec. The computer software is based on a multi-window system and is entirely mouse-driven. All operations can be performed by clicking the mouse on the appropiate windows and buttons. This capability leads to extreme friendliness, ease of operation, and high operator speeds. Image analysis can be done in various ways. Here, we have measured the image contrast and used it to optimize certain parameters. The system is designed to have instant access to: (a) x- and y- alignment coils, (b) x- and y- astigmatism correction coils, and (c) objective lens current. The algorithm is shown in figure 2. Figure 3 shows an example taken from a thin CdTe crystal. The image contrast is displayed for changing objective lens current (defocus value). The display is calibrated in angstroms. Images are stored on the disk and are accessible by clicking the data points in the graph. Some of the frame-store images are displayed in Fig. 4.

Thromboplastin Related Differences in the Determination of International Normalised Ratio: A Cause for Concern?

1994 ◽  
Vol 72 (03) ◽  
pp. 426-429 ◽  
Author(s):  
S Kitchen ◽  
I D Walker ◽  
T A L Woods ◽  
F E Preston
Keyword(s):  
Patient Management ◽  
External Quality Assessment ◽  
Oral Anticoagulant Therapy ◽  
Warfarin Dosage ◽  
External Quality ◽  
External Quality Assessment Scheme ◽  
International Normalised Ratio ◽  
The Uk ◽  
The Relationship

SummaryWhen the International Normalised Ratio (INR) is used for control of oral anticoagulant therapy the same result should be obtained irrespective of the laboratory reagent used. However, in the UK National External Quality Assessment Scheme (NEQAS) for Blood Coagulation INRs determined using different reagents have been significantly different.For 18 NEQAS samples Manchester Reagent (MR) was associated with significantly lower INRs than those obtained using Diagen Activated (DA, p = 0.0004) or Instrumentation Laboratory PT-Fib HS (IL, p = 0.0001). Mean INRs for this group were 3.15, 3.61, and 3.65 for MR, DA, and IL respectively. For 61 fresh samples from warfarin-ised patients with INRs of greater than 3.0 the relationship between thromboplastins in respect of INR was similar to that observed for NEQAS data. Thus INRs obtained with MR were significantly lower than with DA or IL (p <0.0001). Mean INRs for this group were 4.01, 4.40, and 4.59 for MR, DA, and IL respectively.We conclude that the differences between INRs measured with the thromboplastins studied here are sufficiently great to influence patient management through warfarin dosage schedules, particularly in the upper therapeutic range of INR. There is clearly a need to address the issues responsible for the observed discrepancies.

Modern determinants of endometrium hyperplastic processes pathogenesis

2016 ◽  
pp. 137-142
Author(s):  
V.O. Benyuk ◽  
◽  
V.M. Goncharenko ◽  
T.R. Nykoniuk ◽  
◽  
...  
Keyword(s):  
Conservative Therapy ◽  
Solid Phase ◽  
Research Direction ◽  
Immunohistochemical Method ◽  
Results Of Treatment ◽  
Treatment And Prevention ◽  
Receptor Phenotype ◽  
The Relationship ◽  
Endometrial Proliferation

The objective: to еxplore the relationship between the activity of endometrial proliferation and the state of the local immune response in the uterus in the conditions berprestasi process. Patients and methods. Examined 228 women of reproductive and perimenopausal age with endometrial pathology using ultrasound and then performing hysteroresectoscopy. Determination of the concentrations of the cytokines IL-1, IL-2, IL-6 and TNF was performed by solid phase ELISA. Results. Found a trend that confirms the loss of sensitivity to hormones at the stage of malignancy of the endometrium and can be used as diagnostic determinants in determining the nature of intrauterine pathology and criterion of the effectiveness of conservative therapy. Conclusion. Improving etiopatogenetice approach to the therapy of hyperplastic proce.sses of endometrium with determination of receptor phenotype of the endometrium is a research direction in modern gynecology, which will help to improve the results of treatment and prevention of intrauterine pathology. Key words: endometrial hyperplasia,the receptors for progesterone and estrogen, immunohistochemical method.

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