Estimation of the Porosity and Pore Aspect Ratio of Carbonates Using Cloud Transform Method

Vortex-Induced Motion (VIM) is another way to denominate the Vortex-Induced Vibration (VIV) in floating units. The main characteristics of VIM in such structures are the low aspect ratio (L/D < 4.0) and the unity mass ratio (m* = 1.0, i.e. structural mass equal water displacement). The VIM can occur in MPSO (Monocolumn Production, Storage and Offloading System) and spar platforms. These platforms can experience motion amplitudes of around their characteristic diameters. In such cases, the fatigue life of mooring and riser systems can be greatly reduced. Typically, the VIM model testing campaigns are carried out in the Reynolds range between 200,000 and 400,000. VIV model tests with low aspect ratio cylinders (L/D = 1.0, 1.7 and 2.0) and unity mass ratio (m* = 1.0) have been carried out at the Circulating Water Channel facility available at NDF/EPUSP. The Reynolds number range covered in the experiments was between 10,000 and 50,000. The characteristic motions (in the transverse and in-line direction) were obtained using the Hilbert-Huang Transform method (HHT) and then compared with results obtained in experiments found in the literature. The aim of this investigation is to definitely establish the similarity between the VIM and VIV phenomena, making possible to increase the understanding of both and, at same time, allowing some analytical models developed for VIV to be applied to the VIM scenario on spar and monocolumn platforms, logically under some adaption.

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Application of electron holography to material science studies on magnetic domain states of small particles

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100150976 ◽

1993 ◽

Vol 51 ◽

pp. 1028-1029

Author(s):

T. Hirayama ◽

Q. Ru ◽

T. Tanji ◽

A. Tonomura

Keyword(s):

Magnetic Field ◽

Material Science ◽

Science Studies ◽

Phase Distribution ◽

Carbon Film ◽

Objective Lens ◽

Electron Holography ◽

Transform Method ◽

Transmission Electron ◽

Thin Carbon

The observation of small magnetic materials is one of the most important applications of electron holography to material science, because interferometry by means of electron holography can directly visualize magnetic flux lines in a very small area. To observe magnetic structures by transmission electron microscopy it is important to control the magnetic field applied to the specimen in order to prevent it from changing its magnetic state. The easiest method is tuming off the objective lens current and focusing with the first intermediate lens. The other method is using a low magnetic-field lens, where the specimen is set above the lens gap.Figure 1 shows an interference micrograph of an isolated particle of barium ferrite on a thin carbon film observed from approximately [111]. A hologram of this particle was recorded by the transmission electron microscope, Hitachi HF-2000, equipped with an electron biprism. The phase distribution of the object electron wave was reconstructed digitally by the Fourier transform method and converted to the interference micrograph Fig 1.

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Perceptual and Emotional Responses as a Function of Film Aspect Ratio as Viewed on a Television Screen

PsycEXTRA Dataset ◽

10.1037/e413782005-390 ◽

1999 ◽

Author(s):

Norman G. Gordon ◽

Michael J. Johnson

Keyword(s):

Aspect Ratio ◽

Emotional Responses ◽

Television Screen

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Modification of MnS inclusion by tellurium in 38MnVS6 micro-alloyed steel

Metallurgical Research & Technology ◽

10.1051/metal/2020066 ◽

2020 ◽

Vol 117 (6) ◽

pp. 615

Author(s):

Ping Shen ◽

Lei Zhou ◽

Qiankun Yang ◽

Zhiqi Zeng ◽

Kenan Ai ◽

...

Keyword(s):

Fatigue Life ◽

Aspect Ratio ◽

Strong Influence ◽

Experimental Results ◽

Alloyed Steel ◽

Equivalent Diameter ◽

Small Aspect Ratio ◽

Steel Quality ◽

Eds Analysis ◽

Micro Alloyed Steel

In 38MnVS6 steel, the morphology of sulfide inclusion has a strong influence on the fatigue life and machinability of the steel. In most cases, the MnS inclusions show strip morphology after rolling, which significantly affects the steel quality. Usually, the MnS inclusion with a spherical morphology is the best morphology for the steel quality. In the present work, tellurium was applied to 38MnVS6 micro-alloyed steel to control the MnS inclusion. Trace tellurium was added into 38MnVS6 steel and the effect of Te on the morphology, composition, size and distribution of MnS inclusions were investigated. Experimental results show that with the increase of Te content, the equivalent diameter and the aspect ratio of inclusion decrease strikingly, and the number of inclusions with small aspect ratio increases. The inclusions are dissociated and spherized. The SEM-EDS analysis indicates that the trace Te mainly dissolves in MnS inclusion. Once the MnS is saturated with Te, MnTe starts to generate and wraps MnS. The critical Te/S value for the formation of MnTe in the 38MnV6 steel is determined to be approximately 0.075. With the increase of Te/S ratio, the aspect ratio of MnS inclusion decreases and gradually reaches a constant level. The Te/S value in the 38MnVS6 steel corresponding to the change of aspect ratio from decreasing to constant ranges from 0.096 to 0.255. This is most likely to be caused by the saturation of Te in the MnS inclusion. After adding Te in the steel, rod-like MnS inclusion is modified to small inclusion and the smaller the MnS inclusion, the lower the aspect ratio.

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PENINGKATAN KEMAMPUAN GURU BAHASA INDONESIA DALAM MENYUSUN RENCANA PROGRAM PEMBELAJARAN (RPP) SDN 015 PAGARAN TAPAH DARUSSALAM MELALUI METODE PEMBERIAN TUGAS

Primary: Jurnal Pendidikan Guru Sekolah Dasar ◽

10.33578/jpfkip.v5i3.3956 ◽

2017 ◽

Vol 5 (3) ◽

pp. 713

Author(s):

Mukhlis '

Keyword(s):

Aspect Ratio ◽

Duty Cycle ◽

Lesson Plans ◽

Learning Program ◽

School Subjects ◽

Bahasa Indonesia

Based on the observation of some teachers found the symptoms as follows: the lack of abilityof Indonesian teachers in designing learning program (RPP), the learning device is only usedas a supplement and not to the needs of teaching, most teachers again if asked the lessonanswered not have or has not been made. The purpose of this research is to improve theability of Indonesian teachers in designing learning program (RPP) at SDN 015 PagaranTapah Darussalam through the method of administration tasks. This type of research is actionresearch school. Subjects in this study were teachers Indonesian as many as 12 people. Basedon the analysis and discussion can be concluded that the method of administration tasks canimprove the ability of Indonesian teachers in making learning device in SDN 015 PagaranTapah Darussalam through the method of administration tasks. Under these conditions, thelevel of acceptance of teachers increased. The aspect ratio capability Indonesian teachers inpreparing lesson plans through the provision of duty cycle I and II of the increase from 56%and the second cycle to 79%.

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