Video: Qhov kev hloov pauv siab tshaj plaws yog dab tsi?
2024 Tus sau: Miles Stephen | [email protected]. Kawg hloov kho: 2023-12-15 23:36
Rov qab los ntawm The Qhov siab tshaj plaws ntawm kev hloov pauv ntawm qhov taw tes ntawm Kev Ua Haujlwm ntawm ntau nplooj ntawv sib txawv uas yog z = f (x, y) yog ob qhov sib txawv ntawm qhov muaj nuj nqis tiag tiag thiab yog ib chav vector ces qhov qhov siab tshaj plaws ntawm kev hloov ntawm ib qho taw tes $(x, y) hauv D(f)$ yog qhov loj ntawm qhov gradient ntawm, $| abla f(x, y) |$, thiab qhov tsawg kawg nkaus tus nqi ntawm
Piv txwv li, qhov kev hloov ntawm gradient yog dab tsi?
Cov Nqi Hloov . Cov gradient ntawm kab sawv cev rau tus nqi hloov . Cov mis yog li ntawd hloov nyob rau hauv lub y axis muab faib los ntawm cov hloov hauv x axis. Hauv qhov piv txwv no uas sib npaug 10 ÷ 40 = 0.25. Qhov no sawv cev rau tus nqi ntawm 25p ib feeb thiab qhia txog qhov sib npaug tas li.
Ib yam li ntawd, dab tsi yog qhov siab tshaj qhov taw qhia derivative? Muab qhov ua haujlwm f ntawm ob lossis peb qhov sib txawv thiab taw tes x (hauv ob lossis peb qhov ntev), qhov siab kawg tus nqi ntawm cov kev taw qhia derivative thaum ntawd, Duf(x), yog |Vf(x)| thiab nws tshwm sim thaum koj muaj tib cov kev taw qhia raws li gradient vector Vf(x).
Yog li ntawd, ua li cas koj thiaj paub tias txoj kev twg yog qhov chaw siab tshaj?
2x, 2y=2?x,y; Qhov no yog vector parallel rau vector ?x, y?, yog li cov kev taw qhia ntawm steepest ascent yog ncaj qha deb ntawm lub hauv paus chiv keeb, pib ntawm qhov taw tes (x, y). Cov kev taw qhia ntawm qhov siab tshaj plaws yog li ncaj qha mus rau lub hauv paus chiv keeb los ntawm (x, y).
Nyob rau hauv dab tsi kev taw qhia yog f nce sai tshaj plaws?
Gradient yog kev taw qhia ntawm kev ua haujlwm nce ceev tshaj plaws ntawm qhov taw tes.
Pom zoo:
Dab tsi yog qhov kev hloov pauv hloov pauv?
Kev hloov pauv, hauv molecular biology, yog hais txog kev hloov pauv hauv deoxyribonucleic acid (DNA), qhov twg ib qho (ob lub nplhaib) purine hloov pauv rau (ib lub nplhaib) pyrimidine, los yog vice versa
Dab tsi yog qhov txawv ntawm ib puag ncig kev hloov pauv thiab kev hloov pauv qub txeeg qub teg?
Qhov sib txawv ntawm cov yam ntxwv ntawm cov tib neeg ntawm tib hom yog hu ua variation. Qhov no yog inherited variation. Qee qhov kev hloov pauv yog qhov tshwm sim ntawm qhov sib txawv ntawm ib puag ncig, lossis ib tus neeg ua dab tsi. Qhov no yog hu ua environmental variation
Dab tsi tsim cov roj siab thiab nws hloov pauv li cas nrog kev hloov pauv hauv kinetic zog?
Gas siab yog tshwm sim los ntawm kev sib tsoo ntawm cov khoom siv roj nrog rau sab hauv ntawm lub thawv thaum lawv sib tsoo nrog thiab tawm dag zog rau ntawm phab ntsa ntim. Tom qab ntawd cov roj yog cua sov. Raws li qhov kub ntawm cov roj nce, cov khoom tau nce lub zog kinetic thiab lawv cov nrawm nrawm
Dab tsi yog qhov yuam kev loj tshaj plaws yog tias Irina ntsuas qhov ntev ntawm nws lub qhov rais li 3.35 feet qhov yuam kev loj tshaj plaws yog taw?
Kev daws: Qhov yuam kev loj tshaj plaws hauv kev ntsuas ntsuas tau txhais tias yog ib nrab ntawm qhov ntsuas ntsuas
Peb qhov laj thawj tseem ceeb ntawm kev hloov pauv hloov pauv yog dab tsi?
Allele frequencies nyob rau hauv ib tug pej xeem yuav hloov vim plaub lub hauv paus zog ntawm evolution: Natural Selection, Genetic Drift, Mutations thiab Gene Flow. Kev hloov pauv yog qhov kawg ntawm cov alleles tshiab hauv cov noob caj noob ces. Ob ntawm cov txheej txheem tseem ceeb tshaj plaws ntawm kev hloov pauv hloov pauv yog: Natural Selection thiab Genetic Drift