Reference Plane Assisted Sketching Interface for 3D Freeform Shape Design

Abstract In time domain reflectometry (TDR), the main emphasis lies on the reflected waveform. Poor probing contact is one of the common problems in getting an accurate waveform. TDR probe normalization is essential before measuring any TDR waveforms. The advantages of normalization include removal of test setup errors in the original test pulse and the establishment of a measurement reference plane. This article presents two case histories. The first case is about a Plastic Ball Grid Array package consisting of 352 solder balls where the open failure mode was encountered at various terminals after reliability assessment. In the second, a three-digit display LED suspected of an electrical short failure was analyzed using TDR as a fault isolation tool. TDR has been successfully used to perform non-destructive fault isolation in assisting the routine failure analysis of open and short failure. It is shown to be accurate and reduces the time needed to identify fault locations.

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Global Ocean Studies from CALIOP/CALIPSO by Removing Polarization Crosstalk Effects

Remote Sensing ◽

10.3390/rs13142769 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2769

Author(s):

Xiaomei Lu ◽

Yongxiang Hu ◽

Ali Omar ◽

Rosemary Baize ◽

Mark Vaughan ◽

...

Keyword(s):

Polarization Plane ◽

Optical Power ◽

Satellite Observations ◽

Global Ocean ◽

Reference Plane ◽

Orthogonal Polarization ◽

True Value ◽

Before And After ◽

Oriented Parallel ◽

532 Nm

Recent studies indicate that the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) aboard the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) satellite provides valuable information about ocean phytoplankton distributions. CALIOP’s attenuated backscatter coefficients, measured at 532 nm in receiver channels oriented parallel and perpendicular to the laser’s linear polarization plane, are significantly improved in the Version 4 data product. However, due to non-ideal instrument effects, a small fraction of the backscattered optical power polarized parallel to the receiver polarization reference plane is misdirected into the perpendicular channel, and vice versa. This effect, known as polarization crosstalk, typically causes the measured perpendicular signal to be higher than its true value and the measured parallel signal to be lower than its true value. Therefore, the ocean optical properties derived directly from CALIOP’s measured signals will be biased if the polarization crosstalk effect is not taken into account. This paper presents methods that can be used to estimate the CALIOP crosstalk effects from on-orbit measurements. The global ocean depolarization ratios calculated both before and after removing the crosstalk effects are compared. Using CALIOP crosstalk-corrected signals is highly recommended for all ocean subsurface studies.

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Inverse shape design method based on pressure and shear stress for separated flow via Elastic Surface Algorithm

Inverse Problems in Science and Engineering ◽

10.1080/17415977.2021.1914604 ◽

2021 ◽

pp. 1-44

Author(s):

Mohammad Hossein Noorsalehi ◽

Mahdi Nili-Ahmadabadi ◽

Kyung Chun Kim

Keyword(s):

Shear Stress ◽

Design Method ◽

Separated Flow ◽

Shape Design ◽

Elastic Surface

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Visual pathway-related horizontal reference plane for three-dimensional craniofacial analysis

Orthodontics and Craniofacial Research ◽

10.1111/j.1601-6343.2012.01551.x ◽

2012 ◽

Vol 15 (4) ◽

pp. 245-254 ◽

Cited By ~ 2

Author(s):

Y. H. Kang ◽

B. C. Kim ◽

K. R. Park ◽

J. Y. Yon ◽

H. J. Kim ◽

...

Keyword(s):

Three Dimensional ◽

Visual Pathway ◽

Reference Plane

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