<P>과도응답해석이면 어떻고~ 주파수 응답이면 어떠하리~ 가진에 대한 응답만 구하면 땡~아님? 하는 질문을 한번 당돌하게 던져보고 싶었다.</P>
<P> </P>
<P>하지만 주파수 응답에 대해 아는거보다, 과도응답의 메리트를 찾아보려고</P>
<P>두 해석의 차이를 파악하고 싶엇다. 밑의 글이 그 차이를 잘 말해주는듯 하다. </P>
<P> </P>
<P><STRONG>주파수 분석을 사용하는 이유?</STRONG></P>
<P>-<FONT color=#ff0099>TIME DOMAIN의 경우, EXPONENTIAL 하게 DECAY하는 TERM을 불필요하게</FONT></P>
<P><FONT color=#ff0099> 반복적으로 계산해야하나, 주파수 응답에서는 PHASE와 MAGNITUDE만 알면</FONT></P>
<P><FONT color=#ff0099> 정상상태의 응답을 쉽게 구할 수 있다. </FONT></P>
<P><FONT color=#ff0099>- TIME DOMAIN에서, IMPULSE와 입력의 복잡한 계산인 CONVOLUTION이, </FONT></P>
<P><FONT color=#ff0099> FREQUENCY DOMAIN에서는 TRANSFER FUNCTION과 입력의 단순곱으로 </FONT></P>
<P><FONT color=#ff0099> 되어버린다. </FONT></P>
<P><FONT color=#ff0099>- TIME DOMAIN에서 저주파/고주파를 구분하기 힘든 그래프도, FREQUENCY</FONT></P>
<P><FONT color=#ff0099> DOMAIN에서 보면 쉽게 구분이 간다. </FONT></P>
<P> </P>
<P>그러나, 요렇게 딱딱하게 정의한 것도 있다. </P>
<P><!--StartFragment--><STRONG>주파수 응답이란?</STRONG> </P>
<P style="FONT-SIZE: 10pt; MARGIN: 0pt; COLOR: #000000; TEXT-INDENT: 0pt; LINE-HEIGHT: 150%; FONT-FAMILY: '굴림'; TEXT-ALIGN: justify"><FONT color=#ff0099><SPAN style="FONT-SIZE: 10pt; COLOR: #000000; LINE-HEIGHT: 15pt; FONT-FAMILY: '굴림'; LETTER-SPACING: 0pt; TEXT-ALIGN: justify">시스템에 정현파입력(sinusoidal input)을 가했을 때 입력의 크기에 대한 정상상태에서의 출력의 크기의 비, 그리고 입력과 출력 사이의 위상 차.</SPAN> (하아~ 답답하다)</FONT></P>
<P> </P>
<P>처음 글인 왜 주파수 분석을 하는가?에 대한 내용은 INPLUSE와 CONVOLUTION을 과도응답</P>
<P>해석에서 직접 존재를 확인하여 주파수 응답의 의미보다는 과도응답의 신호분석에 대한 이해도가 높아진거 같아 재쑤라고 생각한다. </P>
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첫댓글time domain vs frequency domain analysis have their own pros and cons. While frequency analysis (주파수 응답 분석) which includes modal analysis and frequency response and random vibration is a good way to verify any risk associated with repeated dynamic stress environment condition such as vibration,
time domain transient response analysis (과도응답해석) which includes shock analysis and quasi-static is a good way to verify any risk associated with not repeated but one time event such as shock that is a catastrophic event with dynamic equation dominant and quisi-static that is with mixed static and dynamic.
in a practical manner though, modal analysis is the first tool that has to be used to access structural integrity for various reasons but at the most, it is quick and cost effective but still best in identifying any structural weakness in static or dynamic event implications with the given development time and resource available in our daily work.
첫댓글 time domain vs frequency domain analysis have their own pros and cons. While frequency analysis (주파수 응답 분석) which includes modal analysis and frequency response and random vibration is a good way to verify any risk associated with repeated dynamic stress environment condition such as vibration,
time domain transient response analysis (과도응답해석) which includes shock analysis and quasi-static is a good way to verify any risk associated with not repeated but one time event such as shock that is a catastrophic event with dynamic equation dominant and quisi-static that is with mixed static and dynamic.
in a practical manner though, modal analysis is the first tool that has to be used to access structural integrity for various reasons but at the most, it is quick and cost effective but still best in identifying any structural weakness in static or dynamic event implications with the given development time and resource available in our daily work.