High-speed optical diagnostic that uses interference filters to measure Doppler shifts

Abstract Past expert analyses of communication signals from missing Malaysian Airlines MH370 reconciled Burst Frequency Offset (BFO) errors up to the 6th of 7 arcs for a southerly track. After the 6th arc, the Satellite Data Unit (SDU) power-up or reboot resulted in settling errors in the last two data points that were ignored (first search) and later bounded (second search). For the second search, investigators invoked a high-speed vertical descent to account for BFO errors for the south track fuel-starved scenario. Two searches disappointingly failed to find the implied violent-crash site. We report that interpretations were flawed in suggesting the plane dived vertically, as investigators did not recognize that BFO extrapolations implicitly implied mathematically that the plane was also cruising along the south track, but with no fuel. Our reanalysis used the “Penang Longitude” (PL) theory that predicted a similar southerly track to the 6th arc, and that MH370 subsequently veered eastwards and descended. Doppler Shifts from vertical motions were replaced with plausible horizontal veering and declination of a high-speed aircraft. Veering predicted by the PL theory plus controlled descent plausibly accounts for nominal 7th arc BFO discrepancies for the warm-reboot scenario. We conclude that the fuel-starvation scenario analyses wrongly implied a vertical high-speed crash that ignored the impossible implicit southerly cruise, with no fuel, assumption. Instead, MH370 was piloted to a precise glide landing under power, east of the 7th arc.

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IMPROVEMENT OF METHODS AND TOOLS FOR OVERHEAD CONTACT LINES DIAGNOSTICS

Municipal economy of cities ◽

10.33042/2522-1809-2020-1-154-28-32 ◽

2020 ◽

Vol 1 (154) ◽

pp. 28-32

Author(s):

К. Pereverzyev

Keyword(s):

Real Time ◽

High Speed ◽

High Performance ◽

Laser System ◽

Measurement Range ◽

Contact Lines ◽

Diagnostic Systems ◽

Measuring Systems ◽

Contact Wire ◽

Optical Diagnostic

This paper describes developments of tools and methods in a wear of contact wire aspect, based on optical diagnostic systems and computer vision. In general, such diagnostic systems contribute towards improved service quality, reduced costs and increased security in railways. The contact wire is an important part of the OCL. It interacts with the pantographs which are mounted on the roof of trains and moving at various speeds. It is subject to abrasion, friction, scraping, corrosion, erosion, vibration, arcing and welding at different degrees of severity depending on the wire and collector strip materials, modes of interaction and the environmental conditions that defines the wear of contact wires. Measuring systems which automatically detect the degree of wire wear are necessary in order to carry out efficient OCL infrastructure management and condition-based maintenance of contact wire. The problem of wear measurement characterized by some important determining factors like lighting conditions, background scenery and the disparity of reflexives properties of the contact wire. Besides, in order to conduct an efficient inspection, the measures have to be carried out in a changing speed of inspection train. Finally, an important issues for designing and developing measurement systems are the number of wire in measurement range. Systems have to be able to measure not less than four contact wires which are simultaneously in a range of vision and the contact wire geometric parameters such as height and displacement (stagger). The measuring systems have to acquire, process and store a considerable amount of data in real time. Due to the amount of information to be processed, a high-performance architecture and effective algorithms are needed for real-time monitoring. The hardware and software modernization of a high-speed laser system for a contact wire parameters measurements are examined. Such modernization is fulfilled mostly by implementing a real-time high-speed compression algorithms and using LED backlighting. The results of the measurement of the contact wire’s wear obtained by a modernized high-speed laser system during an inspection trips on a new modern laboratory-car are given in this article. Keywords:, optical diagnostic systems, LED emitter,overhead contact lines of railways

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DGV’s Accuracy Dependence Upon Laser Beam Intensity Profile

Volume 2: Fora ◽

10.1115/fedsm2009-78245 ◽

2009 ◽

Cited By ~ 2

Author(s):

Gerald L. Morrison ◽

Saikishan Suryanarayanan

Keyword(s):

Light Intensity ◽

Laser Beam ◽

High Speed ◽

Pulsed Laser ◽

Laser Frequency ◽

Intensity Profile ◽

Laser Beam Intensity ◽

Doppler Shifts ◽

Ccd Array ◽

Spatially Varying

A Doppler Global Velocimeter (DGV) system was designed for use in high speed rotating equipment at the Turbomachinery Laboratory. Due to the rapidly varying periodic nature of flows inside turbines, compressors, and pumps, it is desirable to use a pulsed laser as the light source. An ND-YAG laser was selected for use based upon the 9 ns pulse duration and the ability for the laser to operate with a 15 MHz light bandwidth which is tunable to the absorption line filter used in the DGV system. However, when applied to the system it was discovered the DGV system did not work properly. The output of a line CCD array used to monitor the laser frequency was closely scrutinized. The light intensity across the laser beam was not Gaussian in nature but contained a very large amount of “noise”. Since the DGV system measures light intensity variations to infer Doppler shifts and hence velocity distributions, the rapidly spatially varying light intensity across the laser beam was suspected as the cause of the system’s inaccuracy. An analysis to quantify how the laser beam light intensity profile noise affects a DGV system accuracy is performed and possible remedies are suggested.

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Non-intrusive optical diagnostic experiments for high-speed flow generator flowfield characterization

Computers & Electrical Engineering ◽

10.1016/s0045-7906(99)00023-3 ◽

2000 ◽

Vol 26 (1) ◽

pp. 67-76 ◽

Cited By ~ 1

Author(s):

Charles A. Terrell ◽

Bagher M. Tabibi ◽

Ja H. Lee ◽

Darrell Spraggins

Keyword(s):

High Speed ◽

High Speed Flow ◽

Optical Diagnostic ◽

Speed Flow ◽

Flow Generator

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Microfabrication research at the National Submicron Facility

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100074331 ◽

1983 ◽

Vol 41 ◽

pp. 86-89

Author(s):

E.D. Wolf

Keyword(s):

Integrated Circuits ◽

Particle Physics ◽

High Speed ◽

New Technology ◽

High Energy ◽

High Energy Particle ◽

New Science ◽

Wide Range ◽

Intermediate Domain ◽

Circuit Function

Most microelectronics devices and circuits operate faster, consume less power, execute more functions and cost less per circuit function when the feature-sizes internal to the devices and circuits are made smaller. This is part of the stimulus for the Very High-Speed Integrated Circuits (VHSIC) program. There is also a need for smaller, more sensitive sensors in a wide range of disciplines that includes electrochemistry, neurophysiology and ultra-high pressure solid state research. There is often fundamental new science (and sometimes new technology) to be revealed (and used) when a basic parameter such as size is extended to new dimensions, as is evident at the two extremes of smallness and largeness, high energy particle physics and cosmology, respectively. However, there is also a very important intermediate domain of size that spans from the diameter of a small cluster of atoms up to near one micrometer which may also have just as profound effects on society as “big” physics.

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Vacuum System to Minimize the Specimen Contamination of High-Performance EM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100077967 ◽

1977 ◽

Vol 35 ◽

pp. 68-69

Author(s):

N. Yoshimura ◽

K. Shirota ◽

T. Etoh

Keyword(s):

Electron Microscope ◽

High Speed ◽

High Performance ◽

High Vacuum ◽

Vacuum System ◽

Pump System ◽

Pumping System ◽

Diffusion Pump ◽

Almost All ◽

Cascade Type

One of the most important requirements for a high-performance EM, especially an analytical EM using a fine beam probe, is to prevent specimen contamination by providing a clean high vacuum in the vicinity of the specimen. However, in almost all commercial EMs, the pressure in the vicinity of the specimen under observation is usually more than ten times higher than the pressure measured at the punping line. The EM column inevitably requires the use of greased Viton O-rings for fine movement, and specimens and films need to be exchanged frequently and several attachments may also be exchanged. For these reasons, a high speed pumping system, as well as a clean vacuum system, is now required. A newly developed electron microscope, the JEM-100CX features clean high vacuum in the vicinity of the specimen, realized by the use of a CASCADE type diffusion pump system which has been essentially improved over its predeces- sorD employed on the JEM-100C.

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The on-line use of histogram data for high-speed correction and alignment of electron microscope images

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100112713 ◽

1984 ◽

Vol 42 ◽

pp. 556-557

Author(s):

William Krakow

Keyword(s):

Power Spectrum ◽

High Speed ◽

Direct Memory Access ◽

Digital Television ◽

Contrast Transfer Function ◽

The Past ◽

High Resolution Tem ◽

On Line ◽

Correction Of Astigmatism ◽

The Fourier Transform

In the past few years on-line digital television frame store devices coupled to computers have been employed to attempt to measure the microscope parameters of defocus and astigmatism. The ultimate goal of such tasks is to fully adjust the operating parameters of the microscope and obtain an optimum image for viewing in terms of its information content. The initial approach to this problem, for high resolution TEM imaging, was to obtain the power spectrum from the Fourier transform of an image, find the contrast transfer function oscillation maxima, and subsequently correct the image. This technique requires a fast computer, a direct memory access device and even an array processor to accomplish these tasks on limited size arrays in a few seconds per image. It is not clear that the power spectrum could be used for more than defocus correction since the correction of astigmatism is a formidable problem of pattern recognition.

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