24小时热门版块排行榜    

查看: 1174  |  回复: 5
当前只显示满足指定条件的回帖,点击这里查看本话题的所有回帖

11hours

铜虫 (小有名气)

[求助] 什么是 first order approximation?

first order approximation 是什么意思?第一近似么?麻烦详细解释一下。
回复此楼

» 猜你喜欢

» 本主题相关价值贴推荐,对您同样有帮助:

已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

11hours

铜虫 (小有名气)

wbcui: 我帮你给了 2011-12-07 19:17:33
维基 order of approximation
In science, engineering, and other quantitative disciplines, orders of approximation refer to formal or informal terms for how precise an approximation is, and to indicate progressively more refined approximations: in increasing order of precision, a zeroth order approximation, a first order approximation, a second order approximation, and so forth.

Formally, an nth order approximation is one where the order of magnitude of the error is at most xn, or in terms of big O notation, the error is O(xn). In suitable circumstances, approximating a function by a Taylor polynomial of degree n yields an nth order approximation, by Taylor's theorem: a first order approximation is a linear approximation, and so forth.
6楼2011-12-07 12:32:26
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖
查看全部 6 个回答

shecf

(文坛精英)

小木虫--警长

优秀版主优秀版主

语境,那里见到的?
业精于勤荒于嬉,行成于思而毁于随!
2楼2011-12-07 11:04:44
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

11hours

铜虫 (小有名气)

11hours: 回帖置顶 2011-12-07 11:30:47
引用回帖:
2楼: Originally posted by shecf at 2011-12-07 11:04:44:
语境,那里见到的?

文献 《Numerical Analysis of Hydrogen Transport Near a Blunting Crack Tip》
作者 P.Sofronis 等
语境
讨论H扩散通量势函数中应力势函数部分。应力部分的势函数等于平均应力乘以H偏摩尔体积。下面跟的这一句“the assumption of dilational distortion is known to be correct to a first order approximation (Hirth, 1977 )”
3楼2011-12-07 11:21:13
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

aduyuandu

银虫 (小有名气)

【答案】应助回帖

★ ★ ★
11hours(金币+2): 就是一阶近似 2011-12-07 12:30:39
wbcui(金币+3): 多谢参与 2011-12-07 19:17:10
引用回帖:
3楼: Originally posted by 11hours at 2011-12-07 11:21:13:
文献 《Numerical Analysis of Hydrogen Transport Near a Blunting Crack Tip》
作者 P.Sofronis 等
语境
讨论H扩散通量势函数中应力势函数部分。应力部分的势函数等于平均应力乘以H偏摩尔体积。下面跟的这一 ...

是不是这个意思 函数在某点处用级数形式展开 忽略高次项而做的近似
4楼2011-12-07 11:26:07
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖
最具人气热帖推荐 [查看全部] 作者 回/看 最后发表
[文学芳草园] 厉娜 +3 张丹枫1991 2026-11-09 5/250 2026-11-09 16:53 by 张丹枫1991
[考博] 售SCI一区T0P文章,我:8.O.55.1.O54,科目全,可伽急 +5 kvewwGtKktqB 2026-11-04 12/600 2026-11-09 13:26 by Equinoxhua
[考研] 售SCI-T0P文章,我:8O.5.5.1.O.54,科目齐全,可+急 +5 ttH3f1oA6ace 2026-11-04 15/750 2026-11-09 13:19 by Equinoxhua
[考研] 售SCI文章,我:8O.5.5.1O.54,科目全,可十急 +6 5sJFDKp2kwuI 2026-11-06 14/700 2026-11-09 11:52 by GwrQVVR6Oenx
[硕博家园] 售SCI一区T0P文章,我:8O.55.1.O.54,科目全,可伽急 +5 5sJFDKp2kwuI 2026-11-06 16/800 2026-11-09 11:47 by GwrQVVR6Oenx
[考博] 售SCI文章,我:8O.5.5.1O.54,科目全,可十急 +5 5sJFDKp2kwuI 2026-11-06 15/750 2026-11-09 11:41 by GwrQVVR6Oenx
[硕博家园] 售SCI一区文章,我:8O5.5.1.O5.4,科目全,可伽急 +4 5sJFDKp2kwuI 2026-11-06 10/500 2026-11-09 08:00 by IhnEQauGmT3K
[考研] 售SCI一区T0P文章,我:8O.55.1.O.54,科目全,可伽急 +3 5sJFDKp2kwuI 2026-11-06 12/600 2026-11-09 06:32 by l48hFd8Nwae2
[公派出国] 售SCI一区文章,我:8.O.55.1.O.54,科目齐全,可伽急 +4 5sJFDKp2kwuI 2026-11-06 8/400 2026-11-09 00:14 by l48hFd8Nwae2
[教师之家] 售SCI一区T0P文章,我:8.O.55.1.O.54,科目齐全,可+急 +4 5sJFDKp2kwuI 2026-11-06 8/400 2026-11-08 23:01 by l48hFd8Nwae2
[教师之家] 售SCI一区T0P文章,我:8.O.55.1.O.5.4,科目全,可+急 +5 5sJFDKp2kwuI 2026-11-06 9/450 2026-11-08 22:46 by l48hFd8Nwae2
[公派出国] 售SCI一区T0P文章,我:8.O.55.1.O.54,科目齐全,可+急 +5 ttH3f1oA6ace 2026-11-04 10/500 2026-11-06 16:12 by 5sJFDKp2kwuI
[公派出国] 售SCI一区文章,我:8.O.551.O.5.4,科目全,可伽急 +6 ttH3f1oA6ace 2026-11-04 12/600 2026-11-06 16:10 by 5sJFDKp2kwuI
[硕博家园] 售SCI一区文章,我:8O5.5.1.O5.4,科目全,可伽急 +4 ttH3f1oA6ace 2026-11-04 11/550 2026-11-06 16:10 by 5sJFDKp2kwuI
[公派出国] 售SCI一区T0P文章,我:8.O.55.1.O54,科目全,可伽急 +5 kvewwGtKktqB 2026-11-04 14/700 2026-11-06 05:10 by qL1cU46YIdK0
[硕博家园] 售SCI一区T0P文章,我:8O.55.1.O.5.4,科目齐全,可+急 +6 kvewwGtKktqB 2026-11-04 16/800 2026-11-06 05:00 by qL1cU46YIdK0
[考博] 售一区SCI文章T0P,我:8O.551.O54,科目全,可十急 +4 ttH3f1oA6ace 2026-11-04 7/350 2026-11-06 02:13 by qL1cU46YIdK0
[考研] 售SCI一区T0P文章,我:8.O55.1.O.54,科目全,可十急 +4 ttH3f1oA6ace 2026-11-04 10/500 2026-11-06 02:04 by qL1cU46YIdK0
[硕博家园] 售SCI-T0P文章,我:8O.5.5.1.O.54,科目齐全,可+急 +3 ttH3f1oA6ace 2026-11-04 9/450 2026-11-06 02:02 by qL1cU46YIdK0
[硕博家园] 售SCI一区T0P文章,我:8.O55.1.O.54,科目全,可十急 +4 hNpp4Y2CGvSC 2026-11-04 12/600 2026-11-06 01:53 by qL1cU46YIdK0
信息提示
请填处理意见