d******e
发帖数: 7844 | 1 PCA和K－means有些相似的地方，都属于最小二乘的框架。
很多Clustering算法也都不robust, PCA的话，robust版本一堆一堆的 |
|
o****o
发帖数: 8077 | 2 PCA=ALS when data is complete
replace the LS in ALS with a robust regression method, you obtain a robust
version of PCA, or RPCA? |
|
e*****r
发帖数: 621 | 3 我要做logit model, 求robust standard error。
以下为具体情况：
Data structure - 100 records, each for a different person. 另外这100个人分别
属于20个cluster，cluster内部存在dependency。
Cluster ID: CID。
Dependent variable - EVENT (1, 0)
Independent variables - V1 (numeric values), V2 (categories: 1, 2, 3, 4)，V3
(dummy: 1, 0), 都是personal characteristics, 没有cluster characteristic.
求robust standard error可以修正cluster内的dependency。
我搜索了一下，好像可以用 proc surveylogistic 或 proc genmod ，但没有找到完全
符合我的情况的code。请大虾帮忙。
多谢！ |
|
y****d
发帖数: 432 | 4 ★★★★★★★★★★★★★★★★★★★★★★★★★★★★★
前面说明：
需要的童鞋请到我的签名档的博客查找！谢谢！发E-mail太累了！
觉得有价值的话可以顶一下，以便更多的人看到！谢谢！
★★★★★★★★★★★★★★★★★★★★★★★★★★★★★
详细介绍
1. Advanced Calculus with Applications in Statistics
2.A History of Probability and Statistics and Their Applications before 1750
3.Markov Decision Processes: Discrete Stochastic Dynamic Programming
4.Probability and Statistical Inference
5.Continuous Univariate Distributions, Vol. 1
6.Continuous Univariate Distributions, Vol. 2
7.The Theory of Measures and Integratio... 阅读全帖 |
|
s*****r
发帖数: 790 | 5 悟空，你又乱用统计术语了。
你知道robust的意思么？什么时候认为算法是robust的？精确又是什么意思？ |
|
a***g
发帖数: 2761 | 6 lol
我对robust也似是而非，要不请你赐教赐教
一直没整明白到底咋就叫robust |
|
k****n
发帖数: 98 | 7 【 以下文字转载自 JobHunting 讨论区 】
发信人: kaixin (胖子), 信区: JobHunting
标 题: A Statistical Consultant Opening in NY/NJ Area, to be filled soon
发信站: BBS 未名空间站 (Fri Aug 30 15:16:48 2013, 美东)
Please contact through mitbbs
============================================================================
=================
A full – time statistical consultant position in a major Pharmaceutical
company manufacturing site
Responsibilities:
The person will provide statistical assessments and develop models for drug
manu... 阅读全帖 |
|
r********n
发帖数: 6979 | 8 这不就是做feature selection么
你可以google一下
方法多了去了
forward， backward， AIC， BIC。。。
你说的这个例子其实就是做一个F-test(anova)
如果用更少predictor的那个model能够得到和更多predictor的model相似的fitness
那就应该选那个predictor比较少的
一般来说这样产生的model更robust
如果你只是先快速检验一下那个model可能会更好一点
可以用这个方法
不过我个人不是太喜欢这么做
因为做出来的model在新的数据里面“不一定”更好
如果愿意多花些时间的话
我一般会先做cross validatiaon或者bootstrapping
重复N次
然后比较两个model在test set里面的fitness
然后选择那个fitness error更低的那个
优点是这样做出来的model一般来说更robust
缺点是花的时间可能是几十倍甚至几百倍
如果你的feature比较多的时候
可以先用uni-variate model， forward, backward等方法找到有限的一些... 阅读全帖 |
|
s****e
发帖数: 1180 | 9 他们的第二轮面试吧。主要问了一些regression的问题：
We use regression to analyze a data set with two explanatory variables, and
it works fine, if we change the data set, increase the number of variables
to be 5, or 6, will the regression method still work? i.e. whether the
regression method is robust to the data set. How do you know the regression
method is robust?
We have many explanatory variables, such as the searching key words, like “
Christmas lights” from google AD, we want to use the variables to predict
the... 阅读全帖 |
|
m********t
发帖数: 94 | 10 好问题
第一个问题怎么答？
5,6 variables regression应该问题不大
考点是哪里？ regularization 或者pca的东东？
第二个呢？
这个有点难了 还要continuous的 我只能想到regression
现场问起来 估计只能胡扯 一个就是group variables
频率高的单独弄 频率低的clutering segement啊
他们的第二轮面试吧。主要问了一些regression的问题：
We use regression to analyze a data set with two explanatory variables, and
it works fine, if we change the data set, increase the number of variables
to be 5, or 6, will the regression method still work? i.e. whether the
regression method is robust to the data set. How do you know... 阅读全帖 |
|
O********9
发帖数: 59 | 11 试着从machine learning的角度回答你的问题。
第一题，如果该regression model被用来预测，那么预测误差随着输入变量个数增加，
先是递减，然后增加。换句话说，并不是输入变量越多越好，而是有一个最优值。这个
最优值，通常取决于问题本身，可以通过cross validation的方法求出来。这是从
performance方面考虑。从robustness角度考虑，增加的变量有可能与已有的变量高度
相关。在极端的情况下，输入变量矩阵列秩不满，从而regression model有无穷多组解
（即colinearity问题）。即使输入变量矩阵满列秩，但是gram matrix的conditional
number太大，regression model的系数的置信区间会很大，model也不会robust。解决
方法，求解之前，先通过feature selection或者PCA，去掉输入变量矩阵的相关性。
第二题，取决于你怎样对“Christmas lights”。你可以设一变量x。如果出现关键词
，则x＝1，否则x＝0。适用于这种离散变量的模型包括但不限于naive ba... 阅读全帖 |
|
y****d
发帖数: 432 | 12 ****************************************************************************
1）这些资料我以前也分享过，但是因为一些原因我的google博客被关闭了，我就不能
维护下载链接了。现在重新整理出来，免费分享给需要的人。
2）这些资料整理在www.svipbook.com不用担心，都是免费下载的。
3）如果大家需要在人大经济论坛下载任何文件，可以跟帖，我在有时间的情况下给你
下载下来然后传到你能下载的网盘比如dropbox or mediafire
4）如果您认为对您有帮助，请转载这个帖子。谢谢
****************************************************************************
★【1】牛人整理的统计学资料
list
1. AdvancedCalculus with Applications in Statistics
2.A History of Probability and Statistics and Their Applications... 阅读全帖 |
|
s**********8
发帖数: 25265 | 13 The bar for risk management has suddenly moved higher for medical device
companies. After numerous product-safety-related recalls and field actions
over the past few years, FDA has dramatically increased its scrutiny of the
product risk management practices, demanding adherence to the current
standard, ISO 14971:2007. With the agency now examining risks in terms of
the worst possible outcome, practices that had been presumed acceptable are
subject to heightened scrutiny. The rate at which FDA is... 阅读全帖 |
|
s**********8
发帖数: 25265 | 14 Failure mode and effects analysis
From Wikipedia,
A failure modes and effects analysis (FMEA) is a procedure in product
development and operations management for analysis of potential failure
modes within a system for classification by the severity and likelihood of
the failures. A successful FMEA activity helps a team to identify potential
failure modes based on past experience with similar products or processes,
enabling the team to design those failures out of the system with the
minimum of e... 阅读全帖 |
|
f**d
发帖数: 768 | 15 这是一本计算神经科学的优秀著作，全文拷贝这里（图和公式缺），有兴趣的同学可以
阅读
如需要，我可以分享PDF文件（－－仅供个人学习，无商业用途）
From Computer to Brain
William W. Lytton
From Computer to Brain
Foundations of Computational Neuroscience
Springer
William W. Lytton, M.D.
Associate Professor, State University of New York, Downstato, Brooklyn, NY
Visiting Associate Professor, University of Wisconsin, Madison
Visiting Associate Professor, Polytechnic University, Brooklyn, NY
Staff Neurologist., Kings County Hospital, Brooklyn, NY
In From Computer to Brain: ... 阅读全帖 |
|
|
|
M******a
发帖数: 6723 | 18 来自主题: Mod_CHN_Hist版 - 奉天兵工厂 https://wwiiafterwwii.wordpress.com/2017/04/03/mukden-arsenal-after-wwii/
Mukden Arsenal after WWII
April 3, 2017 jwh19752 Comments
(Zhang's Gate, the old entrance to Mukden Arsenal)
For people interested in Japanese firearms of WWII, the name Mukden Arsenal
is familiar. The history of the facility after Japan's defeat is less well
known. Under various names, it did survive for some time, producing an odd
mix of WWII weapons after the war's end.
(Mukden Arsenal proofmark during WWII)
Mukden an... 阅读全帖 |
|
p*********e
发帖数: 32207 | 19 ☆─────────────────────────────────────☆
yeemartin (猪头) 于 (Mon Aug 17 05:10:38 2009, 美东) 提到:
看了一篇的文章
有解释为啥Shell Rotella T、Mobil Delvac这些heavy duty diesel oil的Used oil
analysis结果都很突出的原因，普通engine oil是S certification，例如SJ、SM。商
用truck engine oil是C certification， 目前是CI、CJ。C的additive package比S的
牛x很多，但有可能会不兼容乘用车上的catalytic converter。
我的G35目前就在用Shell Rotella T，摩托车下次换油也准备用这个。mobil的
synthetic motorcycle oil 1 quart 12刀，受不了。
Commercial (Diesel) Oil
The additive packages for C (commercial) certification... 阅读全帖 |
|
w*******y
发帖数: 60932 | 20 *- (Limit 256 per person per day) with Code # 9159
Add Free Cinnastix with Code EBCS
Premium toppings $1 extra
Example:
I got all this for $14.05
Large(14") Hand Tossed Pizza
Whole: Robust Inspired Tomato Sauce, Cheese, Pepperoni, Mushrooms
Cooking Instructions:
Change Pizza Remove $5.99
Large(14") Hand Tossed Pizza
Whole: Robust Inspired Tomato Sauce, Cheese, Philly Steak, Premium Chicken
Cooking Instructions:
Change Pizza Remove $6.99
8-Piece Cinna Sti
Icing
Cooking In... 阅读全帖 |
|
w*******y
发帖数: 60932 | 21 Ive decided to compile some resources and tips that will allow you to get a
domain name, web hosting, a basic CMS, web apps and branded email for about
$10/yr.
I think that with a little work and compromise, this combination will be
more than suitable for 70% of people. If you require a shopping cart, FTP
access or any detailed custom development, move on this is not for you. This
is for small business owners who traditionally operate in the brick &
mortar realm who just want a web presence, gro... 阅读全帖 |
|
y*****l
发帖数: 5997 | 22 http://seekingalpha.com/article/302235-the-ultimate-guide-to-so
By Jared Cummans
Solar power is an increasingly popular energy source as well as an
investment option. The growing industry has led to a rapid adoption by
citizens, businesses, and governments to incorporate solar panels on
everything from parking meters to bridges. There are a wide variety of
panels meant for small homes and businesses as well as entire grids and
large buildings. As the industry continues to blossom, the cost of pr... 阅读全帖 |
|
v******a
发帖数: 45075 | 23 中国的资源, 市场, 人口, 领土也够啊, (当然人均资源少).
人口素质, 教育程度, 科技积累, 老毛子比偶们强太多.
以前有两个UCSD的经济学家用计量模型说中国"先经济后政治(改革)"比俄罗斯
robust. 如果Putin能渡过目前混乱的状况, 铁腕建立次序, 10年后和中国比,
这个谁比谁robust还真难下结论. |
|
v******s
发帖数: 272 | 24 What Obama And America Should Learn From China
Shaun Rein, 01.24.11, 12:15 PM EST
There are ways in which Hu Jintao is being wiser than us.
There has been much discussion lately of how China survived the
financial crisis much more robustly than the United States. Many credit
Beijing's centralized power structure, which Sen. Harry Reid mistakenly
(and foolishly) calls a dictatorship under President Hu Jintao.
Political scientist Francis Fukuyama recently wrote that China's command
system allows f... 阅读全帖 |
|
a******n
发帖数: 280 | 25 这位朋友，纽时上那一位作者确实是信誉不良，据实指出这一点，不叫什么大字报。
纽时也有不少信誉良好的作者，发表过对神韵，对法轮功很正面的评论。这儿转载一则
几年前的报
导。
http://www.nytimes.com/2003/07/22/opinion/22iht-edli_ed3_.html
China vs. Falun Gong : After four years of repression, it's time to let
go
By John Li
Published: July 22, 2003
SIGN IN TO E-MAIL
PRINT
BETHLEHEM, Pennsylvania— Four years ago, on the night of July 20, 1999,
a campaign was started across China to round up citizens practicing
Falun Gong, a spiritual movement just rising in the West. From the rust
belt... 阅读全帖 |
|
p*****i
发帖数: 921 | 26 这个 Shaun Rein 会不会就是深海同志？
原文：
http://www.forbes.com/2011/01/24/barack-obama-china-hu-jintao-p
What Obama And America Should Learn From China
Shaun Rein, 01.24.11, 12:15 PM EST
There are ways in which Hu Jintao is being wiser than us.
More from Shaun Rein
There has been much discussion lately of how China survived the financial
crisis much more robustly than the United States. Many credit Beijing's
centralized power structure, which Sen. Harry Reid mistakenly (and foolishly
) calls a dictato... 阅读全帖 |
|
d*****g
发帖数: 441 | 27 老美体会到了中央集权的好处了。
What U.S. utilities can learn from China’s smart grid expansion
China’s state-owned State Grid Company of China signed a strategic
cooperation agreement last month with General Electric to develop smart grid
protocols in the country. The news was another step toward opening the
world’s second-largest consumer of electricity to cutting edge smart grid
technology. The State Grid Company had previously set an aggressive target
of building a robust smart grid in China by 2020 and pla... 阅读全帖 |
|
p**********d
发帖数: 7918 | 28 【 以下文字转载自 Military 讨论区 】
发信人: powerforward (今天你敏感詞了沒有), 信区: Military
标 题: 紐約時報：GE設計的冷卻系統有缺陷
发信站: BBS 未名空间站 (Tue Mar 15 14:15:39 2011, 美东)
Reactor Design in Japan Has Long Been Questioned
By TOM ZELLER Jr.
Published: March 15, 2011
The warnings were stark and issued repeatedly as far back as 1972: If the
cooling systems ever failed at a Mark 1 nuclear reactor, the primary
containment vessel surrounding the reactor would probably burst as the fuel
rods inside overheated. Dangerous radiation would... 阅读全帖 |
|
M*V
发帖数: 3205 | 29 发信站: BBS 未名空间站 (Sat Oct 27 10:00:17 2012, 美东)
Joke: Presidential Debate 2012, Act III
10/22/2012
By Limin Wang
In the evening of October 16, 2012, at the Smack Complex of Hofstra
University on Long Island, New York, President Obama and former governor
Romney had the second finger-to-finger presidential debate. Candy Growly
tried her hardest to moderate them.
Outside the debate building, large swarms of people had decided on their own
to join the show. Some said that they wanted to bring their ow... 阅读全帖 |
|
B*V
发帖数: 3365 | 30 关键词：a strong joint response by the United States and Japan.
读：日美联合起来打邓产党的脸。
关键词：It provided Washington with a perfect opportunity to reassure its
Asian allies that it remains committed to maintaining stability in the Asia-
Pacific region.
读：这个事件给了美帝一个机会去提醒东南亚各国，美帝仍是大哥大霸主。
关键词：the United States called China’s bluff by sending two warplanes
into the zone Tuesday, and Beijing’s response was muted.
读：美帝决定打邓产党的脸，啪啪啪，一轮抽送之后，邓产党响屁都不敢放一个。
好吧，不陪太子了，自己读下去吧：
China's move to establish air defense zone appea... 阅读全帖 |
|
D*V
发帖数: 3096 | 31 http://oecdeducationtoday.blogspot.fr/2013/12/are-chinese-cheat
by Andreas Schleicher
Deputy Director for Education and Skills and Special Advisor on Education
Policy to the OECD's Secretary General
Whenever an American or European wins an Olympic gold medal, we cheer them
as heroes. When a Chinese does, the first reflex seems to be that they must
have been doping; or if that’s taking it too far, that it must have been
the result of inhumane training.
There seem to be parallels to this in educat... 阅读全帖 |
|
E*V
发帖数: 17544 | 32 In the distraction of the scandal-fever swirling through Washington and the
news media, you might have missed the announcement the other day that one of
the great puzzles of number theory had been solved.
What makes the news most fascinating is that the solver isn’t on the
faculty of a top university and wasn’t known until this month to others who
work in the field. He is a Chinese immigrant in his 50s named Yitang Zhang,
a onetime accountant and part-time lecturer at the University of New
Hamps... 阅读全帖 |
|
o***s
发帖数: 42149 | 33 武大化院网站公布的邓鹤翔教授，年轻朝气让人倍生好感
昨日，网爆武大出现85后教授。记者向武大人事部相关负责人求证，教授叫邓鹤翔，生于1985年4月，不久前刚被引入武汉大学化学与分子科学学院，或是该校最年轻教授。
85后教授引来网友羡慕无数
18日，“PETD亚洲善待博士组织”的一条微博在网上炸开了锅。“1985年出生的年轻教授，这是要逆天吗？”博主找出武大新引进的国家青年千人计划学者邓鹤翔，这位生于1985年4月的阳光男孩，被引入武大化院后被评为教授。
“都是85的，人家都教授了，我博士还没毕业，情何以堪！”网友们各种羡慕嫉妒恨，一时间微博转发量上千。不少网友直呼：博士后们原来并非都“聪明绝顶”，还可以充满朝气，“学霸也可以高富帅”！
武大年初引进的博士后海归
记者登录武大化院网站，找到了邓鹤翔的简历。根据简历，小邓2011年在美国加州大学洛杉矶分校取得化学博士学位，先后在该校、加州大学伯克利分校从事博士后研究。今年初，加盟武大化院，现为该院教授。
据了解，邓鹤翔是武汉人，毕业于武汉49中。他曾三次参与完成美国能源部重大项目，两度以第一作者身份在《科学》发表文章。
记者向武大人事部相关... 阅读全帖 |
|
M****o
发帖数: 4860 | 34 Should be Robust Shit Yellow. His full name. |
|
v*****s
发帖数: 20290 | 35 嘿嘿，都是hetzer的错，他说付笛生，我就随手一敲，就爆了猛料了。
至少说明google.com不如baidu.com robust吧，没有正确识别。 |
|
f****r
发帖数: 5118 | 36 政治制度其实可以和计算机系统做个比较
独裁专制共和就是集中性处理，太祖时代，太祖就是一台主机服务器，太祖一人圣断独
裁，所有事情都要太祖做决定，其他人都是瘦型终端，没有处理器，社会的发展以后，
到现在就是政治局九台服务器，劳动人民都没有权，全部都是极瘦型终端，没有大脑，
没有权利，集中到服务器处理，主机/终端方式
民主联邦就是胖型终端，每个终端都很rich，权利很大，你不鸟我，我不鸟你，大家用
TCP/IP HTTP协议宪法互相联系。结果就是大家象Internet一样繁荣
很明显民主联邦好啊，可扩展型强，robust，这就是为什么宝宝同学到处救灾，因为他
是服务器，别人都处理不了，而奥8，布什什么大灾都不去，因为自有部门处理这种事
情，大家都很rich，不需要更多机器来处理
随着人口增长，集中式处理机制越来越承担不了过重的负荷，从政治局到老百姓都很累
。还是Internet好 |
|
t******t
发帖数: 15246 | 37 人比恐龙ROBUST不到哪里去，没有开始星际殖民之前，鸡蛋全在一个篓子里，来个小行
星基本上我们也就恐龙了。 |
|
K*****2
发帖数: 9308 | 38 我很好奇，这个几何平均的算法是怎么来的，数学上是不是更robust |
|
d**********o
发帖数: 578 | 39 The last line of a 17th century poem by John Donne prompted Louise Noble’s
quest. “Women,” the line read, are not only “Sweetness and wit,” but “
mummy, possessed.”
Sweetness and wit, sure. But mummy? In her search for an explanation, Noble,
a lecturer of English at the University of New England in Australia, made a
surprising discovery: That word recurs throughout the literature of early
modern Europe, from Donne’s “Love’s Alchemy” to Shakespeare’s “Othello
” and Edmund Spenser’s “The Faerie Qu... 阅读全帖 |
|
f****0
发帖数: 835 | 40 HORRIBLE toilets. Stagnant puddles buzzing with dengue-spreading mosquitoes.
Collapsing masonry. Lax security. A terrorist attack. India’s preparations
for the 72-nation Commonwealth games, which are scheduled to open in Delhi
on October 3rd, have not won favourable reviews. “Commonfilth”, was one of
the kinder British tabloid headlines. At best—assuming that the organisers
make a last-minute dash to spruce things up—the Delhi games will be
remembered as a shambles. The contrast with China’s pra... 阅读全帖 |
|
L***n
发帖数: 6727 | 41 对不了解此人的兄弟,一点背景介绍,此人任Financial Times 的
associate editor and chief economics commentator,
自吹"widely considered to be one of the world's most
influential writers on economics"(见wiki), 典型的犹太人,
骨子里极端反华, 表面上道貌岸然, 纵观其对中国评论的历史记录, 即使
是貌似公正的为中国经济发展进言, 其隐藏的立场也无不是损害中国的利益
以维护西方白人的利益. 现在连这层遮羞布也不要了, 赤裸裸的宣传美国用
印纸钞票的办法来迫使人民币升职. 此文发表于 FT 网站, 显示其道德水准
之底下, 以基本接近海平面的海拔高度. 一言以蔽之, 其中心思想即是, 我
就是要发烂渣, 就是要耍赖来搞你. 现在QE已经成为美国迫使人民币升值之
基本武器, 未来中国压力会很大.
Why America is going to win the global currency battle
By Martin Wolf
Publ... 阅读全帖 |
|
T**********r
发帖数: 1223 | 42 http://web.stratfor.com/images/writers/CHINA_RARE_EARTH_ELEMENTS.pdf?fn=9617327557
China and the Future of Rare Earth Elements
October 14, 2010
clip_image002
STRATFOR
PDF Version
* Click here to download a PDF of this report
A recent diplomatic spat between China and Japan has heightened territorial
tensions and called attention to China’s growing forcefulness with foreign
powers. One of the more intriguing aspects of this development was China’s
suspension of the export of “rare ea... 阅读全帖 |
|
d*******a
发帖数: 454 | 43 http://www.nytimes.com/2010/11/05/world/asia/05iht-letter.html?ref=china
A Model of Development Worth Building
By AKASH KAPUR
PONDICHERRY, INDIA President Barack Obama arrives in India this weekend,
accompanied by a retinue that occupies two jumbo jets.
His visit coincides with Diwali, the Indian festival of lights, and his
meetings will no doubt have a bright, upbeat tone. But his trip is unlikely
to ease a nagging sense in India that ties between the two countries have
suffered something of a ... 阅读全帖 |
|
g**1
发帖数: 10330 | 44 http://www.cnbc.com//id/40079208
Fed Action Gets an Unexpected Endorsement From India
Published: Monday, 8 Nov 2010 | 8:36 PM ET
When the United States Federal Reserve announced last week that it would
buy $600 billion in Treasury bonds to help bolster the economy, it
quickly came under attack from Germany, Brazil and China, which said
America was trying to devalue the dollar to the detriment of other
nations’ exports.
On Monday, the Fed’s plans earned a hearty endorsement from at least one
fore... 阅读全帖 |
|
K**W
发帖数: 6346 | 45 Prime Minister: "We want a strong relationship with China"
Introduction
Twenty five years ago I came to Hong Kong as a student.
The year was 1985.
Deng Xiaoping and Margaret Thatcher had recently signed the historic Joint
Declaration.
The remarkable story of the successful handover of Hong Kong and the great
progress Hong Kong has continued to make is an example to the world of what
can be achieved when two countries cooperate in confidence and with mutual
respect.
Since then, China has changed ... 阅读全帖 |
|
t******t
发帖数: 15246 | 46 政权如果被一个不值一提的言论就击倒了，那就不是ROBUST的政权。把什么乱七八糟的
东西都放在桌面上，珍珠还是玻璃就一目了然了，像茅这样的经济学家以前还享有盛誉
，现在在言论开放社会呢，已经不值一提了。 |
|
f**k
发帖数: 15238 | 47 那是因为有专制惯性和和演免疫力了
这孙子要是80年代这么说,估计就被吃粮采纳了.
我的中心思想是,误导也是行动,不仅仅是言论了
那就不是ROBUST的政权。把什么乱七八糟的 |
|
s****n
发帖数: 4902 | 48 无产阶级VS资产阶级贵族
http://www.nytimes.com/2010/11/27/opinion/27herbert.html?hp
ovember 26, 2010
Winning the Class War
By BOB HERBERT
The class war that no one wants to talk about continues unabated.
Even as millions of out-of-work and otherwise struggling Americans are
tightening their belts for the holidays, the nation’s elite are lacing up
their dancing shoes and partying like royalty as the millions and billions
keep rolling in.
Recessions are for the little people, not for the corporate chiefs and... 阅读全帖 |
|
t**g
发帖数: 784 | 49 http://online.wsj.com/article/SB10001424052748703585004575604980835504348.html
By TIMOTHY AEPPEL
GREENVILLE, Mich.—When a fast-growing maker of solar equipment broke ground
here in 2006 on the first two of what it said would eventually be six giant
new factories, it seemed the sun was finally shining on this town's
battered economy.
Just months earlier, Sweden's Electrolux AB had shut its Greenville
refrigerator plant, nearly snuffing out what had been the town's marquee
industry for more than a... 阅读全帖 |
|
l****u
发帖数: 248 | 50 筛选主要是极端条件测试，既所谓的鲁棒性(robust control)
现代鲁棒控制是一个着重控制算法可靠性研究的控制器设计方法。其设计目标是找到在
实际环境中为保证安全
要求控制系统最小必须满足的要求。一旦设计好这个控制器，它的参数不能改变而且控
制性能能够保证。
鲁棒控制方法，是对时间域或频率域来说，一般要假设过程动态特性的信息和它的变化
范围。一些算法不需要
精确的过程模型，但需要一些离线辨识。
一般鲁棒控制系统的设计是以一些最差的情况为基础，因此一般系统并不工作在最优状
态。常用的设计方法有
：INA 方法，同时镇定，完整性控制器设计，鲁棒控制，鲁棒PID 控制以及鲁棒极点配
置，鲁棒观测器等。
鲁棒控制方法适用于稳定性和可靠性作为首要目标的应用，同时过程的动态特性已知且
不确定因素的变化范围
可以预估。飞机和空间飞行器的控制是这类系统的例子。
过程控制应用中，某些控制系统也可以用鲁棒控制方法设计，特别是对那些比较关键且
（1 ）不确定因素变化
范围大；（2 ）稳定裕度小的对象。
但是，鲁棒控制系统的设计要由高级专家完成。一旦设计成功，就不需太多的人工干预
。另一方面，如果要升... 阅读全帖 |
|
