2024 Tus sau: Elizabeth Oswald | [email protected]. Kawg hloov kho: 2024-01-13 00:07
Kev ntxhov siab tiag tiag yog qhov kev ntxhov siab txiav txim siab los ntawm kev thauj khoom sai sai ua rau thaj chaw hla ntu ntu tam sim . True Strain (εt): Muaj tseeb hom yog logarithmic thiab engineering strain yog linear. Txawm li cas los xij nws zoo li yuav luag zoo ib yam rau qhov me me deformation vim qhov muaj nqis me me hauv Taylor nthuav dav.
Dab tsi yog qhov txawv ntawm engineering thiab kev ntxhov siab tiag tiag?
Kev nkhaus raws li qhov qub ntu ntu thiab ntsuas qhov ntev yog hu ua engineering stress-strain nkhaus, thaum nkhaus raws li thaj tsam hla tam sim nothiab ntev yog hu ua qhov tseeb stress-strain nkhaus. Engineering kev ntxhov siab yog cov ntaub ntawv siv tau muab faib los ntawm thawj ntu ntu ntawm cov khoom siv.
Koj suav qhov kev ntxhov siab thiab kev nyuaj siab li cas?
True stress=(engineering stress)exp(true strain)=(engineering stress)(1 + engineering strain) where exp(true strain) yog 2.71 tsa rau lub hwj chim ntawm (qhov tseeb strain).
Qhov txawv ntawm kev ntxhov siab thiab kev ntxhov siab yog dab tsi?
Nyob zoo, kev ntxhov siab engineering yog cov ntaub ntawv siv tau muab faib los ntawm thawj ntu ntu ntawm cov khoom siv. Kuj tseem hu ua nominal stress. Kev ntxhov siab tiag tiag yog qhov siv cov khoom sib faib los ntawm thaj chaw hla ntu (qhov hloov pauv raws li lub sijhawm) ntawm cov qauv ntawm qhov load.
Puas muaj tseeb strain ntau dua engineering strain?
Raws li tus txheeb ze elongation nce, qhov tseeb strain yuavdhau los ua qhov tsawg dua qhov kev sib tw engineering thaum qhov kev ntxhov siab tiag tiag ua ntau dua li engineering kev ntxhov siab. Thaum l=4.0 lo ces =3.0 tab sis qhov tseeb strain=ln 4.0=1.39. Yog li ntawd, qhov tseeb strain tsawg dua 1/2 ntawm engineering strain.
Pom zoo:
Puas yog kev nyuaj siab txhais tau tias kev khuam siab?
Ib qho teeb meem yog ib thaiv lossis lwm yam teeb meem uas tus neeg sib tw yuav tsum dhia hla thaum sib tw. Yog tias koj mus rau ntawm qhov teeb meem, tej zaum koj yuav tsis yeej kev sib tw. Puas yog ib qho nyuaj? qhov sib txawv tseem ceeb:
Puas muaj kev puas siab puas ntsws tiag tiag?
Mentalism feem ntau muab faib ua ib pawg ntawm magic thiab, thaum ua los ntawm tus kws ua khawv koob, kuj tseem raug xa mus rau kev puas siab puas ntsws. Txawm li cas los xij, ntau tus kws tshaj lij kev puas siab puas ntsws niaj hnub no feem ntau paub qhov txawv ntawm lawv tus kheej los ntawm cov neeg ua khawv koob, hais tias lawv daim duab kos duab siv cov txuj ci sib txawv.
Puas kev nyuaj siab ua rau koj tus kheej muaj siab?
kev nyuaj siab tsis muaj dab tsi cuam tshuam nrog kev ua qia dub lossis tus kheej kheej. Ib tug zoo, muab neeg tuaj yeem muaj kev nyuaj siab. Kev nyuaj siab feem ntau tuaj yeem yog ib qho kev sib cais, nrog cov tsos mob pom ntawm kev tshem tawm.
Kev ntxeev siab tuaj yeem ua rau muaj kev nyuaj siab?
Qhov cuam tshuam ntawm kev ntxeev siab tuaj yeem tshwm sim sai tom qab kev raug mob thiab pheej mus rau kev laus. Cov cim tseem ceeb suav nrog: teeb meem paub, qhia, lossis tswj kev xav. Kev ntxhov siab, kev nyuaj siab, thiab lwm yam kev mob hlwb.
Dab tsi yog qhov kev nyuaj siab nce siab?
Keeb Kwm: Kev qeeb qeeb ntawm ST-ntu kev nyuaj siab thaum muaj kev ntxhov siab yog xav tias sawv cev an ischemic teb rau kev sim treadmill(ETT). Dab tsi ua rau Upsloping ST kev nyuaj siab? Kev nyuaj siab tab sis kev nce qib ST ntu feem ntau txiav tawm ischemia ua rau.
