Directional error analysis of 2D galvanometer scanning system

AbstractA widely used tool in studying quasi-monoperiodic processes is the O–C diagram. This paper deals with the application of this diagram in minor planet studies. The main difference between our approach and the classical O–C diagram is that we transform the epoch (=time) dependence into the geocentric longitude domain. We outline a rotation modelling using this modified O–C and illustrate the abilities with detailed error analysis. The primary assumption, that the monotonity and the shape of this diagram is (almost) independent of the geometry of the asteroids is discussed and tested. The monotonity enables an unambiguous distinction between the prograde and retrograde rotation, thus the four-fold (or in some cases the two-fold) ambiguities can be avoided. This turned out to be the main advantage of the O–C examination. As an extension to the theoretical work, we present some preliminary results on 1727 Mette based on new CCD observations.

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Tandem scanning confocal light microscopy as compared with x-ray diffraction for characterizing the behavior of clays in fluid-saturated petroleum reservoir rock

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100152719 ◽

1989 ◽

Vol 47 ◽

pp. 148-149

Author(s):

C.J. Stuart ◽

B.E. Viani ◽

J. Walker ◽

T.H. Levesque

Keyword(s):

Light Microscopy ◽

Image Plane ◽

Reservoir Rock ◽

Depth Of Field ◽

Objective Lens ◽

Scanning System ◽

Light Sources ◽

Petroleum Reservoir ◽

Image Recording ◽

Scan Speed

Many techniques of imaging used to characterize petroleum reservoir rocks are applied to dehydrated specimens. In order to directly study behavior of fines in reservoir rock at conditions similar to those found in-situ these materials need to be characterized in a fluid saturated state.Standard light microscopy can be used on wet specimens but depth of field and focus cannot be obtained; by using the Tandem Scanning Confocal Microscope (TSM) images can be produced from thin focused layers with high contrast and resolution. Optical sectioning and extended focus images are then produced with the microscope. The TSM uses reflected light, bulk specimens, and wet samples as opposed to thin section analysis used in standard light microscopy. The TSM also has additional advantages: the high scan speed, the ability to use a variety of light sources to produce real color images, and the simple, small size scanning system. The TSM has frame rates in excess of normal TV rates with many more lines of resolution. This is accomplished by incorporating a method of parallel image scanning and detection. The parallel scanning in the TSM is accomplished by means of multiple apertures in a disk which is positioned in the intermediate image plane of the objective lens. Thousands of apertures are distributed in an annulus, so that as the disk is spun, the specimen is illuminated simultaneously by a large number of scanning beams with uniform illumination. The high frame speeds greatly simplify the task of image recording since any of the normally used devices such as photographic cameras, normal or low light TV cameras, VCR or optical disks can be used without modification. Any frame store device compatible with a standard TV camera may be used to digitize TSM images.

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X-ray mapping without STEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010017027x ◽

1994 ◽

Vol 52 ◽

pp. 508-509

Author(s):

Judith M. Brock ◽

Max T. Otten

Keyword(s):

Life Science ◽

Materials Science ◽

Chemical Elements ◽

Full Description ◽

Scanning System ◽

Elemental Distribution ◽

X Ray ◽

Transmission Electron ◽

Distribution Of Elements ◽

Made In

A knowledge of the distribution of chemical elements in a specimen is often highly useful. In materials science specimens features such as grain boundaries and precipitates generally force a certain order on mental distribution, so that a single profile away from the boundary or precipitate gives a full description of all relevant data. No such simplicity can be assumed in life science specimens, where elements can occur various combinations and in different concentrations in tissue. In the latter case a two-dimensional elemental-distribution image is required to describe the material adequately. X-ray mapping provides such of the distribution of elements.The big disadvantage of x-ray mapping hitherto has been one requirement: the transmission electron microscope must have the scanning function. In cases where the STEM functionality – to record scanning images using a variety of STEM detectors – is not used, but only x-ray mapping is intended, a significant investment must still be made in the scanning system: electronics that drive the beam, detectors for generating the scanning images, and monitors for displaying and recording the images.

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Error Analysis in Neuropsychological Assessment of Verbal Memory and Learning

European Journal of Psychological Assessment ◽

10.1027/1015-5759.11.1.21 ◽

1995 ◽

Vol 11 (1) ◽

pp. 21-28 ◽

Cited By ~ 5

Author(s):

Dietmar Heubrock

Keyword(s):

Error Analysis ◽

Verbal Memory ◽

Verbal Learning ◽

Learning Disorders ◽

Memory And Learning ◽

Auditory Verbal Learning Test ◽

Additional Information ◽

Auditory Verbal Learning ◽

Accurate Picture ◽

Learning Test

Performance on a German version of the Rey Auditory-Verbal Learning Test (AVLT) was investigated for 64 juvenile patients who were subdivided in 6 clinical groups. In addition to standard evaluation of AVLT protocols which is usually confined to items recalled correctly, an error analysis was performed. Differentiating between total errors (TE), repetition errors (RE), and misnamings (ME), substantial differences between clinical groups could be demonstrated. It is argued that error analysis of verbal memory and learning enriches the understanding of neuropsychological syndromes, and provides additional information for diagnostic and clinical use. Thus, it is possible to gain a more accurate picture so that patients can be appropriately retrained, and research into the functional causes of memory and learning disorders can be intensified.

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