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全部话题 - 话题: constrains
1 2 3 4 5 6 7 8 9 10 下页 末页 (共10页)
s*****t
发帖数: 1994
1
来自主题: Computation版 - How to constrain the solution to be positive?
If I am solving linear equations Ax=b, where A is a large
sparse matrix, by use of algorithm LSQR, how can I constrain
the solutions for some x_i to be positive?
Anyone knows?
H********1
发帖数: 2
2
请问Quadratically Constrained Quadratic Programming有什么解决方法?
H********1
发帖数: 2
3
请问Quadratically Constrained Quadratic Programming有什么解决方法?
o*******i
发帖数: 396
4
【 以下文字转载自 EE 讨论区 】
发信人: orioniori (猎人), 信区: EE
标 题: Nonlinear Constrained Optimization 问题求教
发信站: BBS 未名空间站 (Sun Mar 2 14:18:31 2008)
在下是新手,不才, 有初级问题请教达人们:
目标函数 F(x1,x2,....xn)可以closeform表示出来,是个非线性函数(很多erfc函数
和指数运算,非Quadratic)。
约束函数T(x1,x2,....xn)也是一个非线性非quadratic的函数,并且可以closeform表
示出来。
现在给定Tmax上限常量,要求:
[x1,x2,....xn] = argmax{F(x1,x2,....xn)}
s.t.
T(x1,x2,....xn) <= Tmax
有什么比较好的方法,除了穷举之外?
有什么比较好 的reference或者tutorial可以参考?
十分感谢。
o******6
发帖数: 538
5
☆─────────────────────────────────────☆
orioniori (猎人) 于 (Sun Mar 2 16:20:58 2008) 提到:
发信人: orioniori (猎人), 信区: EE
标 题: Nonlinear Constrained Optimization 问题求教
发信站: BBS 未名空间站 (Sun Mar 2 14:18:31 2008)
在下是新手,不才, 有初级问题请教达人们:
目标函数 F(x1,x2,....xn)可以closeform表示出来,是个非线性函数(很多erfc函数
和指数运算,非Quadratic)。
约束函数T(x1,x2,....xn)也是一个非线性非quadratic的函数,并且可以closeform表
示出来。
现在给定Tmax上限常量,要求:
[x1,x2,....xn] = argmax{F(x1,x2,....xn)}
s.t.
T(x1,x2,....xn) <= Tmax
有什么比较好的方法,除了穷举之外?
有什么比较好 的reference或者tutorial可以参考?
A*******s
发帖数: 3942
6
If we fit a regression model with some boundary constrains on some
parameters, is it correct that the model's df is the number of parameters
which do not hit the boundary constraints? wanna confirm this statement.
thanks.
n****o
发帖数: 14771
7
☆─────────────────────────────────────☆
maonvlang (猫女郎) 于 (Fri Jan 13 13:24:15 2012, 美东) 提到:
擦的跟瓷娃娃一样,而且又透又亮, Prescriptives的Flawless Skin Total
Protection Powder SPF 15
他们家很多产品都很好用,而且一直遵循不做广告的政策,要把利益让给消费者,所以
可能名气不及其他品牌,但是产品比大牌都要好,而且价格很便宜。可惜在金融危机中
,不得不关闭店面,现在实行网上销售。http://www.prescriptives.com
Powder通常很难擦的好,但是他们家的这款产品就是你随便拍几下都很好用,实话实说
比CD, MAC什么的强多了。
☆─────────────────────────────────────☆
Gilda (屠龙公主,好女不跟女斗) 于 (Fri Jan 13 13:27:58 2012, 美东) 提到:
mark
☆───────────────────────────────────... 阅读全帖
t*******r
发帖数: 22634
8
来自主题: Parenting版 - 人生的追求
这个主要是自然语言的歧义,还是得靠码工用 formal logics 出马。。。
养娃的三种方式,推养、放养、以及不养。
推养,其实就是 tightly constrained,然后你不断的移动
那个 constraint,于是被 constrained 就往前动。。。
放养,其实就是 loosely constrained。。。但是这样一来
被 constrained 在里面懒惰不懂咋办?OK,你还需要动态加上
一个合适的不断向前移动的 curvature tensor。。。
不养,就是 no constraint,no curvature tensor。。。
比如黑人区街上娃。。。
l**t
发帖数: 64
9
来自主题: Programming版 - 一个C#似疑模板问题
1. C++模板实例化前也会进行一些必要的syntax checking,并不是都留在实例化时才
检查
2. constrain与OO是2个概念。你所举的仅是一种情况。constrain一方面易于编译器定
位错误,这个很重要,另一方面说利于用户阅读的作用,这个不必太夸大了,其实跟注
释的作用区别不大,优点在于二合一了。另如果在注释里写T is derived from A,
where A provides method f(), 按你的逻辑,岂不是更OO?
3. C++里也有constrain。取决于你的需求,如果仅操作规定范畴内的类型,可以按需
求增加constrain。最后如果出现你说的情况,只能说模板库的设计者需求分析有问题
,将一个窄范围使用的模板错误设计为通用范围

for
. it
have
business*
k**********g
发帖数: 989
10
来自主题: Programming版 - 请教一个算法题关于shortest path的

好像是正解.
A shortest path from n0 (starting point) to ny (any point) can be classified
as:
n0 ... ... ny (not touching any constrained point), OR
n0 ... n2 ... ny (touching only n2), OR
n0 ... n5 ... ny (touching only n5), OR
... (more combinations if there are additional constrains)
The best result from the first class is simply computed by removing all
constrained points from the graph.
For each of the remaining classes, the search can be broken down into:
(e.g. for the class that allows n2, r... 阅读全帖
c******i
发帖数: 4091
11
“Opponents of some of these common-sense laws have ginned up fears
among responsible gun owners that have nothing to do with what’s being
proposed and nothing to do with the facts, but feeds into this suspicion
about government,” said Obama.
“You hear some of these quotes: “I need a gun to protect myself from
the government.” “We can’t do background checks because the government is
going to come take my guns away.”
“Well, the government is us. These officials are elected by you. They... 阅读全帖
n******s
发帖数: 1523
12
来自主题: Money版 - Discover apple pay就是鸡肋
看个人了。我是又没credit constrained,也没time constrained,是心情
constrained。lol

time
a*********0
发帖数: 4998
13
来自主题: Money版 - Discover apple pay就是鸡肋
ditto...

看个人了。我是又没credit constrained,也没time constrained,是心情
constrained。lol
time
t*******r
发帖数: 22634
14
来自主题: Parenting版 - 关于刷还是不刷
好吧我把纠结这个的现实问题说了吧。。。俺娃最近把磨美国数学计算题八的半小时的
时间,挪用去看 PBS 有关 life 的 science TV,以及 math comic book 去了。。。
娃虽然是有权在这些范围内调剂,但这都调剂了一个多礼拜了,我正琢磨是 to
constrain 还是 not to constrain,当然更重要的是 to constrain 的目的。。。
经过这个群殴,俺昨晚下了 proximal constraint。。。我给的 proximal constraint
是,可以暂时不磨美国计算题,但不做的时候,晚上复习 5 分钟左右她老忘茬的最近
接触的数学公式和理论,早上上学路上再翻炒一下。。。等她把她目前更感兴趣的东东
整完,再回来继续慢慢磨美国计算题。。。当然最关键的,也是觉得六年后能不能进二
百六,既不是一个靠谱的事,也不是个太适合俺娃的 the star beyond the stars。。
。还是把数学逻辑建模的基础打好,更价格便宜量又足,将来干啥都能混、有底子。。。
当然我就不群殴具体案例了,每家的情况别家都不太了解。。。我就群殴一个可放之四
... 阅读全帖
r********n
发帖数: 1162
15
来自主题: EB23版 - 我想O基本这么做
I think it is worth explaining why I believe that spare visa that fall to
EB3 will go to EB3-ROW first. I know that some people do not share this view
. It may be a subject that we agree to disagree on.
The law setting out the fact that a country may not exceed 7% is given under
INA 202 (a)(2):
The law which appears to be used for spillover says the following:
There is an argument that INA 202 (A)(5) quoted above only deals with Fall
Across.
In that case INA 202 (a)(3) contains the same language... 阅读全帖
d**********y
发帖数: 18
16
来自主题: EB23版 - 我想O基本这么做
如果是引用别人的说法,还请注明出处吧!否则是不是有误导之嫌?
http://www.qesehmk.org/forums/showthread.php?4-EB2-Predictions-
第110页,Spectator的帖子
http://www.qesehmk.org/forums/showthread.php?4-EB2-Predictions
-%28Rather-Calculations%29/page110
Today 09:10 AM #2748
Spectator
Spectator is offline GC-Guru Spectator will become famous soon enough
Join Date Oct 2010 Posts 338
Who Gets Spillover in EB3?
I think it is worth explaining why I believe that spare visa that fall
to EB3 will go to EB3-ROW first. I... 阅读全帖
z********0
发帖数: 9013
17
来自主题: Fitness版 - [合集] 食素与健身
☆─────────────────────────────────────☆
HNM (Map Reduce -Stereo Love) 于 (Sun Apr 3 18:38:10 2011, 美东) 提到:
想问下这里有健身的人食素的吗?牛奶鸡蛋也不沾的那种
谢谢
☆─────────────────────────────────────☆
casact (口令正确) 于 (Sun Apr 3 18:42:21 2011, 美东) 提到:
没有
☆─────────────────────────────────────☆
gejkl (gejkl) 于 (Sun Apr 3 19:59:06 2011, 美东) 提到:
素女经?LOL
☆─────────────────────────────────────☆
jfjf (慕容若) 于 (Sun Apr 3 20:15:25 2011, 美东) 提到:
我有一个女性好朋友,曾经两年吃素,偶尔吃几口鱼,其他几乎全素。
两年后,身体状况很惨烈。她自己非常后悔。 :)

想问下这里有... 阅读全帖
l**********1
发帖数: 5204
18
来自主题: Biology版 - 第一作者相同贡献人数无限制
人家各做一个residue 3D
Molecular Modeling 的话 还是可能的
//www.ncbi.nlm.nih.gov/pubmed/22448988
Crystal structures of Bcl-xL with 118 (PDB entry 2YXJ) and 4 were used to
model the binding poses of our designed compounds with Bcl-xL. In the
binding models, the structure of Bcl-xL in complex with 4 was superimposed
on that of Bcl-xL in complex with 1. The core scaffold of 4 then replaced
the 4′-chloro-2-methyl-1,1′-biphenyl group of 1 to generate the initial
binding model, which was then refined by a 1 ns mo... 阅读全帖
p********3
发帖数: 5750
19
INTRODUCTION — The word "acupuncture" is derived from the Latin words "acus
" (needle) and "punctura" (penetration). Acupuncture originated in China
approximately 2000 years ago and is one of the oldest medical procedures in
the world.
Over its long history and dissemination, acupuncture has diversified and
encompasses a large array of styles and techniques. Common styles include
Traditional Chinese, Japanese, Korean, Vietnamese, and French acupuncture,
as well as specialized forms such as hand,... 阅读全帖
s*******w
发帖数: 2257
20
来自主题: History版 - 独立节读《独立宣言》zt
独立节读《独立宣言》 (2016-07-05 14:18:58)
美利坚合众国第二百四十个独立节之日,重温了一下当时美国立国时杰弗逊起草的《独
立宣言》。
每读一次就不得不再次感慨当时立国之父们的英明及远见。他们在北美这块土地上,抛
弃了大不列颠的君王统治,建立起美利坚这样一个伟大的国家。
一切似乎都是上帝赐予的:这块土地上不仅有雄伟壮观的东部阿普拉契山脉及西部的落
基山脉,而且有着从广袤无际的大草原到美丽宽阔的大海洋,这富绕的土地难道不是一
种恩赐吗?是的,不过上帝恩赐给地球的土地也不仅限于美利坚,算算美利坚的土地面
积,即使现在也只位于全球第三或第四,为何美利坚却成了人们向往的地方呢?
作为移民,也许比这儿生长的美国人有更多的比较。一个感悟是当年《独立宣言》的基
石,即人人生而平等(all men are created equal),天赋给个人的权力等不能受到侵
犯,这包括生命权(Life),自由权(Liberty)及追求幸福的权力(Pursuit of
happiness)。先父们没有意愿创建一个皇权帝制,没有意愿让政府来统治人民。他们的
智慧是政府是为保障人们的安全与幸福而建... 阅读全帖
l**t
发帖数: 6971
21

In reality the reserve ratio is more complicated than a simple 10%. It
doesn't really matter though. The banks are anyway capital constrained, not
reserve constrained.
u***r
发帖数: 4825
22
来自主题: Military版 - PAUL KRUGMAN: Will China Break?
http://www.nytimes.com/2011/12/19/opinion/krugman-will-china-br
Consider the following picture: Recent growth has relied on a huge
construction boom fueled by surging real estate prices, and exhibiting all
the classic signs of a bubble. There was rapid growth in credit — with much
of that growth taking place not through traditional banking but rather
through unregulated “shadow banking” neither subject to government
supervision nor backed by government guarantees. Now the bubble is bursting
— an... 阅读全帖
l**i
发帖数: 8144
23
来自主题: Military版 - Anthropic principle
简单地讲 就是谋事在人 成事在天
认为社会发展沿着某个预定方向发展的理论 都是傻逼理论
--------------------------------------
Anthropic principle
From Wikipedia, the free encyclopedia
In astrophysics and cosmology, the anthropic principle is the philosophical
argument that observations of the physical Universe must be compatible with
the conscious life that observes it. Some proponents of the argument reason
that it explains why the Universe has the age and the fundamental physical
constants necessary to accommodate conscious life. As a ... 阅读全帖
m****e
发帖数: 160
24
哈哈,都是土鳖的锅
美国食品安全问题,全世界都臭名昭著
来看看美国媒体自己的报道,被全世界禁止的美牛
These American Meat Products Are Banned Abroad
By The Daily Meal
Next time you’re enjoying a plate of giant Buffalo wings or chowing down on
a giant steak, think about the size of the animal that must have produced
it. Have you ever noticed how much bigger some U.S. cows, chickens, and
turkeys are than their European counterparts? That’s because many of
America’s animal farms actually mix in synthetic hormones with the
feedstock, making their co... 阅读全帖
c********e
发帖数: 4283
25
来自主题: Military版 - costco的鸡是激素鸡吧
well, I kinda disagree on this one,
my statement is like: "I choose organic chicken despite it's at least twice
as much as non-organic chicken"
but yours is like: "food is so cheap, and its cost nowadays is so
insignificant that why would anyone even mention its price?"
Mine is very constrained to one food item and constrained to myself.
but yours is totally generalized, and implies everyone should take that as a
fact, where it's simply not the case!

bring
looking
should
and
l****z
发帖数: 29846
26
来自主题: USANews版 - RE: Global Warming – Who is in denial?
August 2, 2012 by David Robertson
Every now and then, someone will try to prevent a debate about global
warming by claiming that a consensus of earth scientists supports the
existence of anthropogenic global warming. Well, that so-called “consensus
” is imaginary.
In July of 2008, The Hindu newspaper (India’s national newspaper) published
an article titled “Challenging the basis of Kyoto Protocol”.
Here is an excerpt from that article:
As western nations step up pressure on India and China ... 阅读全帖
f**********n
发帖数: 29853
27
然后斯佳丽在批评司法界有人讲平衡而不讲原则的时候,写到
For when,
in writing for the majority of the Court, I adopt a general rule, and
say, "This is the basis of our decision," I not only constrain lower
courts, I constrain myself as well. If the next case should have such
different facts that my political or policy preferences regarding the
outcome are quite the opposite, I will be unable to indulge those
preferences; I have committed myself to the governing principle.
这一段,可以用斯佳丽判烧国旗属于言论自由来作为旁证。作为保守派,爱美国是最基
本的表现,参见两党大会国旗... 阅读全帖
y***n
发帖数: 2318
28
来自主题: USANews版 - Tesla: More Executive Turmoil? (转载)
【 以下文字转载自 Automobile 讨论区 】
发信人: yeson (快乐着并幸福着...), 信区: Automobile
标 题: Tesla: More Executive Turmoil?
发信站: BBS 未名空间站 (Sat Aug 26 00:30:14 2017, 美东)
"Since December, Tesla has lost two Vice Presidents for Autopilot."
"Having worked with engineers in the past they are indeed prone to wanting
projects they work on to be perfect versus "good enough" to be a viable
source of revenue. But when we are talking a product such as Autopilot that
can cost people their lives no amount of testing and develo... 阅读全帖
y***n
发帖数: 2318
29
来自主题: Automobile版 - Tesla: More Executive Turmoil?
"Since December, Tesla has lost two Vice Presidents for Autopilot."
"Having worked with engineers in the past they are indeed prone to wanting
projects they work on to be perfect versus "good enough" to be a viable
source of revenue. But when we are talking a product such as Autopilot that
can cost people their lives no amount of testing and development is enough
until the product is flawless."
"My position on this company and its stock has not changed. I would run to
the nearest exit. Walking i... 阅读全帖
l******h
发帖数: 2
30
Highly reputational company with very competitive compensation for all
positions.
Please send in your resume and position/positions you like to apply to my
email address below.
h*******[email protected]
All resumes will be deliver to hiring manager directly. Act fast!
Thanks!
Silicon Engineering Group
Sr. Physical Design Timing Engineer
Timing (STA) Manager
Senior Physical Design Engineer
CAD Manager - Front-End Design and Verification
Sr. CAD Engineer - Place & Route / Physical Design Engineer
Sr. CA... 阅读全帖
T*********r
发帖数: 11175
31
来自主题: Faculty版 - 这种情况怎么办?
如果导致很多结果都错了
当然需要写文章改正
这个对事不对人
没什么大不了的
直接写吧
我最近正在搞arxiv fight
被三位大佬点名,写在abstract里说我们的模型被别的constraint给rule out了
文章里写了这类理论只有我们模型对解释那个anomaly是能work的
但有其他constrain
其实他们推到constrain的时候,用的assumption其实并不general
我们正在写东西fight back
m***e
发帖数: 428
32
来自主题: Faculty版 - 一位青年经济学家的死亡
一位青年经济学家的死亡
作者:金颖琦
在苏哲林(Che-lin Su)的Facebook主页上,时间还停留在一个月前,他当时正访问苏
黎世大学。苏哲林是芝加哥大学布斯商学院运筹学副教授,他是师长眼中的学术新星。
但学术黄金期刚刚开启,却又仓促结束,是癌症带走了他的生命。
2015年7月31日,苏哲林因癌症辞世,年仅41岁。8月3日,世界计量经济学会(
TheEconometric Society)发表了一篇悼文,作者为Lars Peter Hansen, Jim Heckman
, Jean-Pierre Dube, Ali Hortacsu 和 Todd Munson。“在离世前,他一直积极乐观
。而今我们失去了一位有潜质的学者,一位好同事,一位挚友”文章写道。
苏哲林热爱学术与教学,喜欢与同事分享自己的观点与想法。7年前,30出头的苏哲林
刚加入布斯商学院,此前他就拥有深厚的管理学与运筹学背景,31岁获得斯坦福管理学
与工程博士学位,而后在西北大学凯洛格商学院与国家经济研究局(NBER)从事博士后
研究。期间,他还在耶鲁、哈佛及芝加哥大学等知名学府有访学经历,并兼授课程。在
加入布... 阅读全帖
t***n
发帖数: 546
33
a piece if paper 不行吧。要balance好US/international stock,bond,large/med/
small cap,而且每支基金都有点blender。还有,这些基金散布在几个broker/IRA账户
里面,所以这里也有一个constrain,就是不能无限制的买卖任何一支基金。
所以最好就是做一个有constrain的linear regression,得出在目前状况下趋近目标
allocation的最优解。

to
index
l******h
发帖数: 2
34
Highly reputational company with very competitive compensation for all
positions.
Please send in your resume and position/positions you like to apply to my
email address below.
h*******[email protected]
All resumes will be deliver to hiring manager directly. Act fast!
Thanks!
Silicon Engineering Group
Sr. Physical Design Timing Engineer
Timing (STA) Manager
Senior Physical Design Engineer
CAD Manager - Front-End Design and Verification
Sr. CAD Engineer - Place & Route / Physical Design Engineer
Sr. CA... 阅读全帖
a****t
发帖数: 7049
35
来自主题: Money版 - Discover apple pay就是鸡肋
不是难不难的问题,是撸有个rate,这里多撸了那里就少撸了,你没算机会成本,比如
本来就有别的卡可以撸。有多少人撸得credit constrained?我猜没几个,大多是time
constrained。
a****t
发帖数: 7049
36
again,我又要问了,你们搞MS的难道还credit constrained而不是time constrained
?以前是缺卡不够撸而不是卡在被揭发前搞得到几次Kate?
t*******r
发帖数: 22634
37
来自主题: Parenting版 - 九年级的娃
纯从技战术角度探讨,为啥初中 4 年不用课余时间练习,但高中就需要占很多时间?
或者从数字男 optimization algorithm 的角度问,这个算法的时间复杂度为啥不能
constrain 在 fixed time budget 里?可能的原因到底是以下的哪一个:
是 stop criteria 不给力呢?
还是 core engine 的 convergence 速度不够呢?
还是这个要解决的问题本身 over-constrained(比如 math modeling 的
requirements 搞得太狠了啥的。。。)?
t*******r
发帖数: 22634
38
来自主题: Parenting版 - 九年级的娃
纯从技战术角度探讨,为啥初中 4 年不用课余时间练习,但高中就需要占很多时间?
或者从数字男 optimization algorithm 的角度问,这个算法的时间复杂度为啥不能
constrain 在 fixed time budget 里?可能的原因到底是以下的哪一个:
是 stop criteria 不给力呢?
还是 core engine 的 convergence 速度不够呢?
还是这个要解决的问题本身 over-constrained(比如 math modeling 的
requirements 搞得太狠了啥的。。。)?
t*******r
发帖数: 22634
39
来自主题: Parenting版 - 真的应该为孩子牺牲10几年吗?
我想了想。。。从益智游戏的角度说,我觉得这么说,初中欧氏几何学
(不算 transformation geometry,那个才是有很多离散问题),
本来是一个连续数学的问题,而这些难题其实是把一个连续问题 constrain
成一个一个离散的问题,而这个 constrain 的过程,生造的成分很大。
如果真的要玩有关离散方面的益智游戏,为啥不去玩离散数学,比如娃版
数论图论之类,那些问题 by nature 是离散的。。。如果不存在连续数
学意义上的 “Any” 算子,那是因为 by nature 不存在。。。比如通常
你无法直接用解线性方程的方法,去解有关质数的问题。。。是因为
by nature,distributive property 和 unique prime factorization
是两个不同的问题(切蛋糕 vs 离散瓢虫点阵)。。。这两个 “Any”
的定义本身就不一样。。。而不是以生造的姿势弱化 “Any” 算子。。。
另外跟 chess / jigsaw puzzle 类比的话,那俩游戏本来,by nature,
本来就是离散数学的问题。。。
t*******r
发帖数: 22634
40
来自主题: Parenting版 - 真的应该为孩子牺牲10几年吗?
我想了想。。。从益智游戏的角度说,我觉得这么说,初中欧氏几何学
(不算 transformation geometry,那个才是有很多离散问题),
本来是一个连续数学的问题,而这些难题其实是把一个连续问题 constrain
成一个一个离散的问题,而这个 constrain 的过程,生造的成分很大。
如果真的要玩有关离散方面的益智游戏,为啥不去玩离散数学,比如娃版
数论图论之类,那些问题 by nature 是离散的。。。如果不存在连续数
学意义上的 “Any” 算子,那是因为 by nature 不存在。。。比如通常
你无法直接用解线性方程的方法,去解有关质数的问题。。。是因为
by nature,distributive property 和 unique prime factorization
是两个不同的问题(切蛋糕 vs 离散瓢虫点阵)。。。这两个 “Any”
的定义本身就不一样。。。而不是以生造的姿势弱化 “Any” 算子。。。
另外跟 chess / jigsaw puzzle 类比的话,那俩游戏本来,by nature,
本来就是离散数学的问题。。。
t*******r
发帖数: 22634
41
来自主题: Parenting版 - 关于刷还是不刷
嗯,俺语法错误,应该是
To constrain
or not to constrain
that is the question
我去改一下
t******l
发帖数: 10908
42
来自主题: Parenting版 - AMC 8 Problem 25 --- 解答
其实 “猴版 intuitional constrained optimization” +
“猴版 intuitional transformation geometry” 的直觉,
也能算很严格了。比如这么解释:
(1)这题两个 constraint 是 “大正方形” 加 “四个小正方形”。
constraint 90 度旋转对称。constraint 的要求是 no-intersection。
(2)所以满足 constraint 的最大的正方形的中心,必然在旋转对称点。
(3)而正方形中心固定之后,在给定的倾角 alpha,在该倾角下找到
最大的正方形,那就是个 trivial problem。
(4)所以问题就是找到最大正方形所对应的倾角 alpha,于是绕场一周
就完事了。(其实因为 90 度旋转对称,绕场 1/4 圈就够了)。
但是问题就是中学老师不认猴版 intuitional,中学娃也说不清猴版
intuitional。
这个最终还是 “显然” 的定义,中学老师觉得 ”基于石器时代的严格
石器逻辑的欧氏几何” 是非常 “显然”,但马工觉得 “猴版 intuitiona... 阅读全帖
t******l
发帖数: 10908
43
来自主题: Parenting版 - AMC 8 Problem 25 --- 解答
酱油版 constrained optimization 大部分属于是马工基础课之一。
数学系如果有 constrained optimization 课,那多半都是钻牛角尖型极端理想工整的
情况。
况且这只是思想、概念和浅说,具体数学工具不超过六年级数学。
d****g
发帖数: 7460
44
来自主题: Parenting版 - 独立节读《独立宣言》zt (转载)
【 以下文字转载自 History 讨论区 】
发信人: smilhaNew (ha), 信区: History
标 题: 独立节读《独立宣言》zt
发信站: BBS 未名空间站 (Wed Jul 6 11:12:23 2016, 美东)
独立节读《独立宣言》 (2016-07-05 14:18:58)
美利坚合众国第二百四十个独立节之日,重温了一下当时美国立国时杰弗逊起草的《独
立宣言》。
每读一次就不得不再次感慨当时立国之父们的英明及远见。他们在北美这块土地上,抛
弃了大不列颠的君王统治,建立起美利坚这样一个伟大的国家。
一切似乎都是上帝赐予的:这块土地上不仅有雄伟壮观的东部阿普拉契山脉及西部的落
基山脉,而且有着从广袤无际的大草原到美丽宽阔的大海洋,这富绕的土地难道不是一
种恩赐吗?是的,不过上帝恩赐给地球的土地也不仅限于美利坚,算算美利坚的土地面
积,即使现在也只位于全球第三或第四,为何美利坚却成了人们向往的地方呢?
作为移民,也许比这儿生长的美国人有更多的比较。一个感悟是当年《独立宣言》的基
石,即人人生而平等(all men are created equal),天赋给... 阅读全帖
d******8
发帖数: 1972
45
http://www.cnn.com/2011/10/25/tech/gaming-gadgets/smaller-cheap
Editor's note: Amy Gahran writes about mobile tech for CNN.com. She is a San
Francisco Bay Area writer and media consultant whose blog, Contentious.com,
explores how people communicate in the online age.
(CNN) -- Smaller tablet computers that are significantly more affordable and
portable than the iPad are finally starting to hit the United States -- and
they could hit a crucial sweet spot in the consumer market.
Recently Kobo annou... 阅读全帖
y***n
发帖数: 2318
46
"My position on this company and its stock has not changed. I would run to
the nearest exit. Walking is too slow."
"Since December, Tesla has lost two Vice Presidents for Autopilot."
"Having worked with engineers in the past they are indeed prone to wanting
projects they work on to be perfect versus "good enough" to be a viable
source of revenue. But when we are talking a product such as Autopilot that
can cost people their lives no amount of testing and development is enough
until the product i... 阅读全帖
Q*K
发帖数: 3464
47
http://slacy.com/blog/2011/03/what-larry-page-really-needs-to-d
What Larry Page really needs to do to return Google to its startup roots
Posted on March 24, 2011 by slacy
I worked at Google from 2005-2010, and saw the company go through many
changes, and a huge increase in staff. Most importantly, I saw the company
go from a place where engineers were seen as violent disruptors and
innovators, to a place where doing things “The Google Way” was king, and
where thinking outside the box was discou... 阅读全帖
D****o
发帖数: 12808
48
来自主题: Fitness版 - [合集] Apr 1st,叔叔也有奶
☆─────────────────────────────────────☆
anoia (high estrogen man) 于 (Fri Apr 1 09:53:00 2011, 美东) 提到:
奔个B cup。。。
一周增了5 lb。。。按照某专家说法,应该都是fat,那估计都长胸上了。。。
☆─────────────────────────────────────☆
zephyr1130 (西风残照【坐直了接着灌】) 于 (Fri Apr 1 10:19:26 2011, 美东) 提到:
胳膊不错,CUP也不错
☆─────────────────────────────────────☆
cidywestla ((青红西瓜)) 于 (Fri Apr 1 10:27:59 2011, 美东) 提到:
叔叔可以喂养小孩了

☆─────────────────────────────────────☆
zephyr1130 (西风残照【坐直了接着灌】) 于 (Fri Apr 1 10:34:23 2011, 美东) 提到:
可... 阅读全帖
j**p
发帖数: 1257
49
来自主题: LeisureTime版 - 这个五毛Eric x. Li的英文如何?
在MSNBC看到Eric X. Li和裴敏新辩论中国民主的结尾。
Eric X. Li 用流利的中式口音英语吐槽东亚文明不适合民主,证据就是台湾韩国前总
统纷纷入狱...
完整的video在这里。
http://blog.hiddenharmonies.org/2012/07/aspen-ideas-festival-de
找到几篇大作,都是发在nytimes等等主流英文媒体上的。
司马南看到大概只能感叹英文老师死得早了。
李世默:西方民主正在走向灭亡
DEMOCRACY’S COMING DEMISE
SHANGHAI -- As the U.S. presidential election shifts into high gear this
week Washington hosts China's Vice President Xi Jinping heir apparent of the
emergent super power. The world's most powerful electoral democracy and the
largest one-party s... 阅读全帖
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