acoustic microscopy – 나선형의 패턴
Fourier Transform Analysis (FTA)는 청각영상(acoustic image)의 주기성을 시험하는 방법이다. 아 래의 figure를 보면 A는 단일한 회색의 점무늬가 패턴을 보이지 않고 존재하는데 반대로 침을 회전 했을때는 B에서처럼 나선형의 패턴이 분명히 보인다. 이 나선형의 패턴
소음원의 중첩에 따른 SPL의 증가
오토바이 1에서 발생하는 소음을 L_1, 오토바이 2에서 발생하는 소음을 L_2라 하고, 오토바이 1과 오토바이 2에서 동시에 발생하는 소음을 L_(1+2)라 하면 다음과 같은 관계가 성립한다.
L_(1+2)=10log(〖10〗^(L_1/10)+〖10〗^(L_2/10) )
실험을 통해 측정된 S
acoustic style,
American idol have accpted
the use of music instrument
since Season 9.
Fantasia Barrino
She was the bread-winner
of ex-boy friend and her daugter.
The adding back-story
is also the startegy of American idol for being more popular.
The developped internet voting system make viwers
could communicate with contestants and production crew
in interactive way.
analysis was conducted. From the acquired spectrum Fig.3b, the particle was identified as another Nb precipitate. Prior to this study, it was certain that Nb precipitates as particles above 50nm in steel, but identifying precipitates below this size was not clarified. However, from this analysis conducted on carbon extraction replicas using an FE-SEM, it was proven that Nb can indeed precipitate
1. Purpose
Find the unknown specimens by using
XRD(X-ray diffractometer).
2. Theory
- Principle of XRD
A method for the structure
analysis
Using monochromatic X-ray
Involving interference of waves
described by Bragg’s law
- Bragg’s law
When x-rays are scattered from a crystal lattice, peaks of scattered intensity are observed which correspond to the fol