Rotationally asymmetric figure measurement of optical flat using rotational shear phase measuring deflectometry

2018 ◽  
Author(s):  
Kewei E ◽  
Kun Li ◽  
Shangkuo Liu ◽  
Yan Zhou ◽  
Dahai Li ◽  
...  
Keyword(s):  
Rotational Shear

A Tertiary thrust fault on the southern margin of the Bovey Basin

1971 ◽  
Vol 108 (1) ◽  
pp. 61-67 ◽  
Author(s):  
C. M. Bristow ◽  
D. E. Hughes
Keyword(s):  
Thrust Fault ◽  
Open Pit ◽  
Southern Margin ◽  
Thrust Plane ◽  
Borehole Drilling ◽  
Ball Clay ◽  
The Hill ◽  
Rotational Shear

SummaryGeological investigations and borehole drilling on the southern margin of the Bovey basin around Mainbow ball clay mine and Ringslade open pit have shown that Devonian slate up to 30 m thick is superimposed on Tertiary sediments. A drag fold beneath the slate indicates that the slate has moved eastwards over the Tertiary material. As the slate is relatively intact and not disaggregated, hillcreep cannot be responsible for the superimposition. A large landslip involving a rotational shear cannot be responsible, as the movement plane dips into the hill over too large an area. The southern margin of the Bovey basin is therefore interpreted as a thrust fault of Tertiary age, with thrust plane dipping 10° to 30° S. It is suggested that this is a rejuvenation of the Variscan thrust recognized in the Bickington area and further west in the Holne area and that the movement on the Tertiary thrust is related to the dextral wrench movement on the Sticklepath fault.

Error Analysis of Absolute Interferometric Testing Based on Reconstruction of Rotational Shear

2011 ◽  
Vol 346 ◽  
pp. 620-626
Author(s):  
Xin Jia ◽  
Ting Wen Xing
Keyword(s):  
Error Analysis ◽  
Coordinate System ◽  
Absolute Measurement ◽  
Zernike Polynomials ◽  
Motion Error ◽  
Rotation Error ◽  
Angle Rotation ◽  
Rotational Shear

Recently most of modern absolute measurement rotation the flats or spheres in the interferometer. We review traditional absolute testing of flats methods and emphasize the method of reconstruction of rotational shear. The rotation of the lens can lead to some errors such as angle rotation error, center excursion error and other coordinate system motion error. 36 Zernike polynomials are used to generate 3 flats and Matlab are used to simulate the arithmetic. There have some phase problems on FFT arithmetic in Matlab which can cause some errors. Results are shown about how these errors influence the accuracy. The analysis results can also be used in other interferometer systems which have the motion of the coordinate system.

scholarly journals Annular split level shear tester sebagai alat pengukur karakteristik aliran bahan padat butiran

REAKTOR ◽  
2017 ◽  
Vol 5 (1) ◽  
pp. 16
Author(s):  
Setia Budi Sasongko
Keyword(s):  
Shear Tester ◽  
Rotational Shear

Jenike Shear Tester telah dikenal dengan baik sebagai suatu instrumen untuk mengetahui sifat pengaliran dari suatu bahan padat butiran. Hasil pengukuran bahan berdasarkan Jenike Shear Tester ini telah direkomendasikan sebagai suatu standar. Akan tetapi instrument ini memiliki eberapa keterbatasan antara lain: keterbatasan untuk geseran horizontal demikian juga dengan jumlah titik untuk membuat kurve patahan, diperlukan beberapa sample untuk membuat kurve patahan, dan juga adanya ketidak uniform antara bagian yang dekat dengan cincin dengan bagian tengah cincin. Untuk mengatasi hal ini, kemudian Peshcl mengembangkan shear tester jenis totational (RO 200), akan tetapi pada kenyataan masih terdapat beberapa kelemahan. Dengan mengurangi kelemahan yang terdapat pada  Peschl Shear Tester, maka pada penelitian ini, dikembangkan Shear Tester jenis Annular Split Level dengan hasil pengukuran yang mendekati hasil Jenike Shear Tester.Keyword : Shear Tester, Rotational  Shear Tester, Annular Split Level Shear Tester

Comparison of three rotational shear cell testers: Powder flowability and bulk density

2015 ◽  
Vol 283 ◽  
pp. 103-112 ◽  
Author(s):  
Sara Koynov ◽  
Benjamin Glasser ◽  
Fernando Muzzio
Keyword(s):  
Bulk Density ◽  
Shear Cell ◽  
Powder Flowability ◽  
Rotational Shear

scholarly journals Neutral Hydrogen in the Magellanic Clouds

1999 ◽  
Vol 190 ◽  
pp. 37-44
Author(s):  
L. Staveley-Smith ◽  
S. Kim ◽  
S. Stanimirović
Keyword(s):  
Atomic Hydrogen ◽  
Large Scale ◽  
Milky Way ◽  
Velocity Dispersion ◽  
Neutral Hydrogen ◽  
Distribution Functions ◽  
Magellanic Clouds ◽  
Self Gravity ◽  
Rotational Shear ◽  
Compact Array

We review observations of neutral atomic hydrogen (HI) in the Magellanic Clouds (MCs). Being the nearest gas-rich neighbours of the Milky Way the MCs give us an excellent opportunity to study in detail the structure and evolution of the interstellar medium (ISM) and the effect of interactions between galaxies. HI in emission provides a probe of the structure and velocity field of the Clouds, allowing the study of their velocity dispersion, 3-D structure, and large-scale total-mass distribution. Recent data from Australia Telescope Compact Array surveys reveal a morphology (for both Clouds) which is heavily dominated by the effects of local star-formation, rotational shear, fragmentation, self-gravity and turbulence. The new data, which has a spatial resolution down to 10 pc, also allows the study of the distribution functions in velocity and mass for HI clouds. We discuss the morphology, dynamics and giant shell population of the LMC and SMC.

scholarly journals Surface Differential Rotation of Evolved Fast Rotators

2004 ◽  
Vol 215 ◽  
pp. 294-299
Author(s):  
P. Petit ◽  
J.-F. Donati ◽  
G. A. Wade ◽  
J. D. Landstreet ◽  
T.A.A. Sigut ◽  
...  
Keyword(s):  
Differential Rotation ◽  
Surface Brightness ◽  
Binary Systems ◽  
Temporal Evolution ◽  
Doppler Imaging ◽  
Short Term ◽  
Single Star ◽  
Magnetic Structures ◽  
Tidal Forces ◽  
Rotational Shear

Zeeman-Doppler Imaging enables one to estimate the short term temporal evolution of surface brightness and magnetic structures, under the effect of differential rotation. We present here spectropolarimetric observations secured between 1998 and 2002 for two evolved active stars: the K1 subgiant of the RS CVn system HR 1099 and the single FK Com giant HD 199178. Differential rotation is detected both from brightness and magnetic images, indicating that the rotational shear, roughly solar in magnitude for the single star, is significantly weaker in the binary system. This result suggests that tidal forces, rather than stellar evolution, could be responsible for the lower rotational shear and thus the longer spot lifetime reported for binary systems.

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