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全部话题 - 话题: oscillator
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g****g
发帖数: 1828
1
来自主题: WaterWorld版 - Normal distribution
In probability theory, the normal (or Gaussian) distribution, is a
continuous probability distribution that is often used as a first
approximation to describe real-valued random variables that tend to cluster
around a single mean value. The graph of the associated probability density
function is “bell”-shaped, and is known as the Gaussian function or bell
curve:[nb 1]
f(x) = \tfrac{1}{\sqrt{2\pi\sigma^2}}\; e^{ -\frac{(x-\mu)^2}{2\sigma^2}
},
where parameter μ is the mean (location of the pe... 阅读全帖
s*****e
发帖数: 115
2
来自主题: Joke版 - 教中学物理最怕聪明孩子
After you jump, the elevator will undergo a harmonic oscillation (if
assuming the simplest spring-mass system and ignoring dumping). The tension
in the cable (which hangs the elevator) also oscillates, and thus there's NO
steady reading of "weight" of the elevator.

发帖数: 1
3
新假说声称解决了物理学最大的五个问题
物理学家提出了一个新模型,他们说解决了现代物理学中未解答的5个最大的问题,一
次全部解释了怪异的暗物质、微中子振荡、重子生成(baryogenesis)、宇宙膨胀、以及
强作用电荷共轭-宇称问题(strong CP problem,强CP问题)。
新模型称为SMASH,提出我们只需要六个新粒子,来协调物理学标准模型中的所有这些
差距。新模型背后的团队认为这将不会那么难测试。
该模型是由法国和德国物理学家组成的团队所发展出来的。他们认为不需要对标准模型
进行任何重大调整,只需要一些新的添加。
这还在初期阶段,但这是一个非常酷的论点,因为其他模型是设计来解释量子力学的奥
秘,例如超对称性(supersymmetry),需要添加数百个我们从来没有见过足迹的新粒子。
反过来说,SMASH只需要六个:三个微中子,一个费米子(fermion)和一个包括两个粒子
的场。(在物理学中,场是物理或数学实体,在空间和时间上对每个点都有一个值。粒
子是场的激发态。)
为了要让你知道这5个基本(重大)问题是什么,我们将浏览所有这5个问题,从暗物质开
始。
2.暗物质Dar... 阅读全帖
m*******s
发帖数: 758
4
来自主题: PsychoAnalysis版 - 对什么都不在乎
u are right.
This week, my advisor was questioning me in this issue and helped me review
my performance in the past few years.
He pointed out me that the most quality I lacked is "commitment" because I
always oscillated between future careers and achieved so little. This
oscillation also appears in my relationship due to lack of commitment.
The reason is that I am not in a good 'inspired' status, though I was when
in China, where I outperformed others and I was aggressive and ambitious,
which w
M*****8
发帖数: 17722
5
【 以下文字转载自 SanFrancisco 讨论区 】
发信人: MB80528 (肥猫(Contrarian)[食MM而肥]), 信区: SanFrancisco
标 题: Re: SPY 的预测 (有说明) (转载)
发信站: BBS 未名空间站 (Tue Aug 2 23:55:40 2011, 美东)
.......................
Oscillator 不告诉你起跌的幅度。
Oscillator 对 Trend 没有有效的调整功能。
s*****t
发帖数: 1994
6
A Lenticular Cloud Over Hawai'i
Credit & Copyright: Peter Michaud (Gemini Obs.)
Explanation: Can a cloud do that? Actually, pictured above are several clouds all stacked up into one striking lenticular cloud. Normally, air moves much more horizontally than it does vertically. Sometimes, however, such as when wind comes off of a
mountain or a hill, relatively strong vertical oscillations take place as the air stabilizes. The dry air at the top of an oscillation may be quite stratified in moisture
b******l
发帖数: 1632
7
来自主题: Biology版 - Mathematical biology
有些不同意见。不理解 bio-question,就无法真正使用数学工具来提出自己的见解,
就会落入 化工的 simulation 的老路去。
事实上,太多组是被数学工具玩儿,而不是在玩儿数学工具。
举个简单例子:bio-oscillation 的一种基本模型:translation/transcription 模型
,由于 transportation 导致的时间差造成一个非线性系统可以产生恰好的 over-
shooting 从而导致震荡,这个与数学工具完全无关,而是反映的一种数学上对生物问
题的洞察力,即历史依赖性问题;再比如讨论 bio-oscillation 是不是由纯粹自发的
stochastic fluctuation 引发的非线性系统的震荡,还是需要一个外在的推动来把体
系由 bi-stable 状态推进到 hysteretic,与 stochastic process 的数学工具无关,
而是一种数学思想在生物学领域的应用。
不理解生物体系的基本特征和常见现象,就无从运用数学思想和洞察力来透过纷杂的现
象看到本质的 design principles 和 basic mo
s*******m
发帖数: 2572
8
来自主题: Biology版 - 做果蝇电生理好做吗?
倒也没什么不好做,系统成体系就好。
也不一定要去做whole cell,field recording做oscillation最近发表状况挺好的,
Mark stopfer push的很凶,不过以下一作讲到的成功率,比glenn turner的whole
cell貌似低更多,汗。。。。。
Odor-evoked neural oscillations in Drosophila are mediated by widely
branching interneurons.Tanaka NK, Ito K, Stopfer M.J Neurosci. 2009 Jul 1;29
(26):8595-603.
m***f
发帖数: 1622
9
来自主题: Biology版 - 做果蝇电生理好做吗?
果蝇的oscillations 和小鼠的slow oscillations (up-and-down state)还是不同吧

29
a****c
发帖数: 339
10
来自主题: Biology版 - 说说牛老板的一些点评
Wiki: Amplitude is the magnitude of change in the OSCILLATING variable. Is t
his PA phenomenon oscillating? You could just say PA magnitude.
Well, it is really trivial. You are a smart guy. Things will work out eventu
ally.

LENGTH
G*****m
发帖数: 198
11
可能是因为高级脑区要频繁大量的调用其他脑区的信息,制造了很多oscillation wave
,然后运动脑区被oscillation搞的也要来个周期性活动,身体就不由自主地来回踱步
(神经活动的有规律振荡)。
a********k
发帖数: 2273
12
花了一个小时,深深的鄙视一下自己的无聊行径!!
125 蔡亮 男 1980年11月 复旦大学 生命
科学 2007年12月毕业于[美国]北卡大学 [美国]加州大学旧金山分校 博士后
Cai L, Mostov K. Polarity is destiny. Cell. 2009 Nov 13;139(4):660-2. PubMed
PMID: 19914162; PubMed Central PMCID: PMC2900917.
Cai L, Makhov AM, Schafer DA, Bear JE. Coronin 1B antagonizes cortactin and
remodels Arp2/3-containing actin branches in lamellipodia. Cell. 2008 Sep
5;134(5):828-42. PubMed PMID: 18775315; PubMed Central PMCID: PMC2570342.
Cai L, Makhov AM, Bear JE. F-actin... 阅读全帖
l**********1
发帖数: 5204
13
来自主题: Biology版 - 每个细胞都有一样的DNA?
Bingo
人的血红细胞的生物钟韵律调控都可以不用DNA 的 transcription-translation feedback loops
各个血红细胞应该不会只有一套proteomics 不然生物钟韵律调控如何实现?
Nature. 2011 Jan 27;469(7331):498-
Circadian clocks in human red blood cells.
//www.ncbi.nlm.nih.gov/pubmed/21270888
full text link:
//www.dormivigilia.com/wp-content/uploads/2011/02/nature09702.pdf
Abstract
Circadian (~24 hour) clocks are fundamentally important for coordinated physiology in organisms as
diverse
as cyanobacteria and humans. All current models of the molecular circadi... 阅读全帖
l**********1
发帖数: 5204
14
推荐下
图灵那理论的来龙去脉的一篇综述
Roth S.
Mathematics and biology: a Kantian view on the history of pattern formation
theory.
Dev Genes Evol. 2011 Dec;221(5-6):255-
Abstract
Driesch's statement, made around 1900, that the physics and chemistry of his
day were unable to explain self-regulation during embryogenesis was correct
and could be extended until the year 1972. The emergence of theories of
self-organisation required progress in several areas including chemistry,
physics, computing and cybernetics. Two p... 阅读全帖
f*****0
发帖数: 489
15
来自主题: EE版 - 有谁用过OPA627BM的片子
opa627 is a high-speed voltage feedback amp. As such, it is very easy to get
into oscillation if you aren't careful with its layout, and power supply
decoupling.
it doesn't have high current capability so short of mis-wiring, your cuircit
is almost surely oscillating. the chip is likely done.
go through the datasheet and pay particular attention to decoupling and
layout and get a scope to see the output wave form.
w********e
发帖数: 385
16
oscillation? there was a joke that if you want to design an amplifier, try t
o design an oscillator, it will turn out to be an amplifier, vice versa.
n***r
发帖数: 25
17
来自主题: EE版 - 请教模拟电路高手
I agree with cosmos. it could be charge pump.
It depends what kind of amplifier. Some amplifiers have charge pump
integrated. Some chopper amplifiers may have switches working at the
frequency as well.
It could also be the switching power supply problem.
Seems it's not oscillation. when circuit oscillates, it's usually not small
signal.
Why connecting 10kohm to vin+? You are adding resistor thermal noise to your
circuit. And it's easier to pickup external interference signal.
f*****0
发帖数: 489
18
来自主题: EE版 - 请教模拟电路高手

you could have a split personality; someone could have pee'd in your
rice bowl; Maybe yes maybe no.
thanks, that's very helpful.
can
then don't come out saying that the 500khz ripple is due to the charge
pump if you don't have a clue how fast it is running.
not to mention that stupid comment about oscillation usually being
large. if you had the faintest clue about opamp oscillation and had seen
it on a scope, you wouldn't have said that.
a******e
发帖数: 331
19
What kind of non-linear circuit? Normally the special simulation engine are
used for RF simulation such as Mixer, Oscillators etc.
从频域进行 Harmonic balance simulation, it is solving KCL/KVL in frequency
domain, in hspice, you can use .hb .hbac etc and ADS is strong in this.
Aother type analysis for non-linear RF circuit is shooting newton, in hspice
use .sn .snosc(for oscillators) .snnoise etc., in Cadence use PAC, PSS(
periodical steady state). Golden gate is good too. Popular for switch cap
circ
s******u
发帖数: 142
20
大家好。国内本科硕士,美国土校的phd,26周岁,男,现在二年级。下学期秋季想找
一份实习,为时一学期左右。
本人的个人情况:
做过的项目 (tape-out 并测试过工作的):
国内:在某863项目里用0.18um 工艺做过GPS 3.2G的分频器以及LDO等电路。
某市项目里用0.18um 工艺做过的2.4G分频器。
美国:某NIH项目里用0.35um 工艺做过一些基本模电模块:opamp,amplifier,
bandgap,oscilator (低频),comparator啥的。
某MOSIS的项目里,做过 ring oscillator,injection locked frequency divider
for ISM band
以及某些做的课程project但是未能测试通过或者没有tape-out的:
8-bit SAR ADC
GPA:3.9/4.0
会议论文若干。
对于地域没啥要求,希望做的东西和IC design相关。
不知道有没有哪位过来人有机会可以推荐一下。谢谢!联系邮箱:v****[email protected]
t****1
发帖数: 827
21
来自主题: EE版 - 求教RLC电路阶跃响应
absolutely no oscillation in his configuration. one terminal of the R, L, C
is tied to a ideal voltage source, which has 0 impedance to ground. The
other terminal of R, C, L is tied to ground.There is no way that such
configuration can cause oscillation. very fundamental undergraduate stuff.
x***g
发帖数: 454
22
1. Draw the connection with 3 single-ended inverters in series. Can you do
with 2 inverters? Why? Draw the differential version.
2. How to size PMOS transistor sizes relative to NMOS to get the symmetric
rising/falling edges? Why we want to do this?
3. Now if we increase all the transistors’ sizes by 10X, what will be the
new oscillation freq ?
4. Typical ring oscillator duty cycle variation range across PVT?
Which one of the PVT variations affects the most? Methods to adjust
the duty cycle clos... 阅读全帖
x***g
发帖数: 454
23
1. Draw the connection with 3 single-ended inverters in series. Can you do
with 2 inverters? Why? Draw the differential version.
2. How to size PMOS transistor sizes relative to NMOS to get the symmetric
rising/falling edges? Why we want to do this?
3. Now if we increase all the transistors’ sizes by 10X, what will be the
new oscillation freq ?
4. Typical ring oscillator duty cycle variation range across PVT?
Which one of the PVT variations affects the most? Methods to adjust
the duty cycle clos... 阅读全帖
s*******y
发帖数: 130
24
有点BT啊……
JOB REQUIREMENTS
* MSEE required, Ph.D. preferred with 5+ years experience in mixed-signal IC
design, with emphasis on analog design. * Experience with several analog/
mixed-signal IC development cycles including design, simulation, layout and
testing.
* Knowledge of PLLs, DLLs, differential ring oscillators, LC tank
oscillators, bandgap references, biasing techniques, SERDES, I/Os,
controllers, high-speed digital circuits and linear feedback system
techniques.
* Experience with transist... 阅读全帖
w*****1
发帖数: 220
25
PUBLICATIONS
² Xun Jia, Sudip Chakravarty, \An explanation of the dichotomy between
Fermi arcs and Fermi pockets
in underdoped high-Tc superconductors," arXiv:0811.1056.
² Pallab Goswami, Xun Jia, Sudip Chakravarty, \Quantum oscillations in
graphene in the presence of
disorder and interactions," Accepted by Phys. Rev. B., arXiv:0809.3536.
² Ivailo Dimov, Pallab Goswami, Xun Jia, Sudip Chakravarty, \Competing
order, Fermi surface recon-
struction, and quantum oscillations in underd
T*********r
发帖数: 11175
26
很多实验啊
有继续测oscillation的角度之类的(neutrino mass matrix),
有测neutrino/anti-neutrino分别oscillation是否一致的(以检测CPT的)
有测是否有neutrinoless doublebeta decay的(lepton number violation)
。。。。。
甚至还有对撞机上找heavy pseudoDirac neutrino或者lepton number violation的
(当然这个有点牵强)
做理论模型的主要在flavor physics部分
一方面看neutrino的flavor和别的能不能扯上点,主要在gut之类的理论中
一方面看neutrino自己的flavor,有没有什么能indicate中微子理论模型的
还有不少和cosmology扯一块的,比如做些leptogenesis之类
当然还有做乱七八糟neutrino新模型的
不过这些估计得等我们理解了electron质量从哪里来的再说
呵呵
l*b
发帖数: 4369
27
来自主题: Physics版 - 要是光能很方便的调频就好了
我知道可以用调频光做激光雷达,可以测透明物体的厚度和位置
在光纤里面可以探损(找出折射率异常的地方),或者在只有一头accessible的情况下
侧光纤长度(比如海底光纤断了,就可以用扫频光输入,然后通过反射信号和local
oscillator做heterodyne之后分析出断点的位置)。
还可以在光纤上做一串sensor,比如通过在光纤上做微结构,让每个sensor的折射率随
温度变化。然后从光纤一头输入,分析这一头的反射信号,通过调节local oscillator
可以individually读出所有sensor的测量值。
p*******g
发帖数: 2976
28
【 以下文字转载自 Biology 讨论区 】
发信人: albertsmwk (.)(.), 信区: Biology
标 题: 第一批“青年千人计划”生物类@publication列表@
发信站: BBS 未名空间站 (Thu Aug 18 15:04:16 2011, 美东)
花了一个小时,深深的鄙视一下自己的无聊行径!!
125 蔡亮 男 1980年11月 复旦大学 生命
科学 2007年12月毕业于[美国]北卡大学 [美国]加州大学旧金山分校 博士后
Cai L, Mostov K. Polarity is destiny. Cell. 2009 Nov 13;139(4):660-2. PubMed
PMID: 19914162; PubMed Central PMCID: PMC2900917.
Cai L, Makhov AM, Schafer DA, Bear JE. Coronin 1B antagonizes cortactin and
remodels Arp2/3-containing actin branche... 阅读全帖
T**E
发帖数: 1892
29
Neutrino experiment affirms faster-than-light claim - November 18, 2011
An updated version of this story is now available (see 'Neutrino experiment
replicates faster-than-light finding').
It is a remarkable confirmation of a stunning result; but most physicists
remain skeptical. That seems the most probable outcome of a release of new
data expected on 17 November from researchers with the Italian OPERA
collaboration, who say they have confirmed their controversial finding that
flighty subatomic ... 阅读全帖
L*m
发帖数: 235
30
2015诺贝尔物理奖
获奖人:Arthur B McDonald、Takaaki Kajita
获奖领域:实验高能物理
获奖原因:发现了中微子震荡,并因此证明了中微子具有质量
相关文章
Measurement of the Rate of νe+d→p+p+e− Interactions Produced by B8
Solar Neutrinos at the Sudbury Neutrino Observatory
Q. R. Ahmad et al. (SNO Collaboration)
Phys. Rev. Lett. 87, 071301 – Published 25 July 2001
Direct Evidence for Neutrino Flavor Transformation from Neutral-Current
Interactions in the Sudbury Neutrino Observatory
Q. R. Ahmad et al. (SNO Collaboration)
Phys. Rev. Lett. 89, 011301 – ... 阅读全帖
x********i
发帖数: 905
31
2016 Breakthrough Prize in Fundamental Physics
The Breakthrough Prize in Fundamental Physics recognizes major insights into
the deepest questions of the Universe.
To the five teams below and their combined 1,377 team leaders and members
the award is presented for the fundamental discovery and exploration of
neutrino oscillations, revealing a new frontier beyond, and possibly far
beyond, the standard model of particle physics.
Daya Bay Reactor Neutrino Experiment, led by Yifang Wang, Institute of... 阅读全帖

发帖数: 1
32
【 以下文字转载自 Joke 讨论区 】
发信人: zero7 (007), 信区: Joke
标 题: 新假说声称解决了物理学最大的五个问题
发信站: BBS 未名空间站 (Mon Nov 7 20:27:47 2016, 美东)
新假说声称解决了物理学最大的五个问题
物理学家提出了一个新模型,他们说解决了现代物理学中未解答的5个最大的问题,一
次全部解释了怪异的暗物质、微中子振荡、重子生成(baryogenesis)、宇宙膨胀、以及
强作用电荷共轭-宇称问题(strong CP problem,强CP问题)。
新模型称为SMASH,提出我们只需要六个新粒子,来协调物理学标准模型中的所有这些
差距。新模型背后的团队认为这将不会那么难测试。
该模型是由法国和德国物理学家组成的团队所发展出来的。他们认为不需要对标准模型
进行任何重大调整,只需要一些新的添加。
这还在初期阶段,但这是一个非常酷的论点,因为其他模型是设计来解释量子力学的奥
秘,例如超对称性(supersymmetry),需要添加数百个我们从来没有见过足迹的新粒子。
反过来说,SMASH只需要六个:三个微中子,一个费米子(... 阅读全帖
p******e
发帖数: 58
33
来自主题: Science版 - neutrino mass
Anyone has some inside information about the recent result
on K2K long baseline neutrino Oscillation Experiment?
I heard some rumer that they have significant lower rate
than expected, is it true? This should be very important
results.
For people at/near Caltech,
there will be a special seminar at 2pm today in 248 Lauritsen.
Makoto Sakuda of KEK, Japan will present the preliminary results
from K2K long baseline neutrino Oscillation Experiment.
If I were there, I would definitely go. Anyone cou
M*********m
发帖数: 2024
34
What do you mean it's not a measurement? From my point of view, measurement is
the classical perturbation to the origrinal quantum system. Such as
considering the photons in a 3D resonant cavity. There is a hole on the
sidewall with a very small dimension compared to the length of the box and I
could couple the light out of the box. The photons originally oscillate with a
definite frequency inside the box, then after I change the size of the box,
The photons oscillate with several frequencies ac
m****s
发帖数: 18160
35
☆─────────────────────────────────────☆
njsummer (查有此牛, 嗯。。就这样吧) 于 (Mon Jul 16 08:12:05 2012, 美东) 提到:
申请新泽西(NewJersey)版版主
因为站务不让旧贴重新顶, 所以只好发新帖子。
是否已阅读:1)《站规》2)《版务操作简易手册》?:
是的
[申请ID]:
njsummer
[申请版面]:
新泽西(NewJersey)版
[申请职务]:
版主
[版务经验]:
目前车版版主,熟悉版务操作
[申请纲领]:
现任版主辞职,
愿意用自己的时间经验为广大网友服务,繁荣版面营造愉快的灌水氛围
[版规草案]:
让大家都能开开心心的来灌水,一起繁荣版面
☆─────────────────────────────────────☆
mahjong (相忘于江湖) 于 (Mon Jul 16 09:18:49 2012, 美东) 提到:
支持先,虽然希望翠儿留任。。

☆─────────────────────────────────────☆
yechaox (小Y)... 阅读全帖
w*******y
发帖数: 60932
36
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y***k
发帖数: 1078
37
来自主题: _Stockcafeteria版 - [zt] 一位期货老将的经验之谈(转)
更多摘要补充:
1。 四要素: 价格\风险\收益\可能性
1) 价格: 价格没有绝对高低,而只有相对高低,只能从技术上判断价格高低.
比如,以做多为例,价格未突破上方阻力位,可以说是高价,一旦突破站稳,就成低价了

价格是我们交易要考虑的唯一对象 (忽略消息)
-- 我的理解:只有价格是可靠的,oscillators也基本不可靠。有一句话说的好
:oscillators are good servants, but poor masters.
2)价格是风险和收益的统一.价格包含了一个空间概念和时间概念.空间上就是支撑阻
力位, 时间上就是方向.支撑阻力位加方向,你就可以判断出风险有多大收益有多大.
3)价格包含的风险和收益是一个可能性。
4) 价格变动的中期方向比短期方向更容易辨别和把握.因为中期变动主要取决于相对
稳定的供求关系和市场的中期交易成本(平均线)决定的多空优势与劣势以及市场上占上
风的交易习惯,这些因素稳定一些;短期趋势主要取决于因获利产生的平仓冲动\随机消
息产生的情绪冲动等,就非常不稳定.
2。 仓位控制
如何控制仓位?我认为下列几条是必须坚持的:
一... 阅读全帖
b**t
发帖数: 656
38
来自主题: _pennystock版 - Hindenburg Omen (ZT)
加抄一段:
The Omen finally got triggered today, first, a quick refresher of what the
Omen is:
It is a set of conditions, and rules that when all are met, greatly
increases the odds of a large sell-off, or crash of the markets. In fact no
crashes in the last 22 years have happened, that did not first have a
confirmed signal of a Hindenburg Omen. Just because all the conditions have
been might, and it becomes a confirmed Hindenburg Omen does not guarantee a
crash, only greatly increases the chances of... 阅读全帖
s*****t
发帖数: 1994
39
来自主题: _Astronomy版 - Astronomy Picture of Day: a Cloud Over Hawaii
A Lenticular Cloud Over Hawai'i
Credit & Copyright: Peter Michaud (Gemini Obs.)
Explanation: Can a cloud do that? Actually, pictured above are several clouds all stacked up into one striking lenticular cloud. Normally, air moves much more horizontally than it does vertically. Sometimes, however, such as when wind comes off of a
mountain or a hill, relatively strong vertical oscillations take place as the air stabilizes. The dry air at the top of an oscillation may be quite stratified in moisture
c**********w
发帖数: 1746
40
现在人民似乎又要选择毛了
继续折腾
社会发展不收敛啊,OSCILATION
w****j
发帖数: 5581
41
来自主题: History版 - 距离宪政最近的日子(后记)
罗素的西方哲学史也不是什么难找到书。我就贴一下好了:
... Against the more insane forms of subjectivism in modern times there have
been various reactions. First, a half-way compromise philosophy, the
doctrine of liberalism, which attempted to assign the respective spheres of
government and the individual. This begins, in its modern form, with Locke,
who is as much opposed to ‘enthusiasm’-the individualism of the
Anabaptists-as to absolute authority and blind subservience to tradition. A
more thorough-going revolt leads to... 阅读全帖
C********g
发帖数: 9656
42
http://my.cnd.org/modules/wfsection/article.php?articleid=30096
从昨天(09/22/2011)旁晚开始,物理界好像炸了锅,疯传一则消息:CERN (日内瓦
)和Gran Sasso (巨岩,意大利)的中微子实验发现,中微子的传播速度超过光速!
今天纽约时报等大小报纸也跟着凑热闹:二十世纪最有名的物理公式,E=mc^2
中的c 不是常数了 !似乎爱因斯坦就要完蛋了!
别忙着下结论,先看一下CERN 和Gran Sasso 到底干了什麼。CERN 和Gran Sasso 两个
实验室我都去过。前者拥有世界最大的粒子加速器,后者是世界最大的地下的粒子和天
体物理实验室。CERN -Gran Sasso 的中微子实验,想法很简单,如图1所示,在日内瓦
的CERN(图左边)产生一束中微子,射向意大利的Gran Sasso (图右边)。 他们 测
量中微子从CERN 飞到Gran Sasso的时间,又知道,CERN 到Gran Sasso的距离,就测得
中微子的飞行速度了。
由于地球是球状的,中微子从 CERN 到Gran Sasso... 阅读全帖
w****j
发帖数: 5581
43
来自主题: History版 - 虎肉兄的孩儿很可爱呀!
Hongjie是大一轮。他也是Rice的postDoc,老板是Smalley,所以后来纳米管做得风生
水起啊。据说他和Lieber的关系不怎么样。跟风快也是水平,其实CuiYi比风一般还是要快
半拍。出结果的时候貌似跟风,其实起手的时候还都是满早的,这也是眼光啊,能比较
早地看出一个想法的价值。他不是那种往深度走的人。以前他的那篇InP的Science文章
,里面的主要公式都错了,文章里讨论了半天dipole oscillation, 结果公式给了个静
电场的公式。当年Lieber那一系列InP的文章,里面还有In2O3的TEM图拿出来混的事情
。Hongjie出身于Lieber那个组,但做事情还是深入多了,虽然和Cees Dekker,
Kouwenhoven(这个是俺的偶像),McEuen这帮物理学家比有所不及。不过据说Cees
Dekker往生物那边转了,不知最近怎么样,有一段时间不关注他们了。你提的这两位貌
似都是生化那边的吧?不是俺的方向啊。
i*****y
发帖数: 3449
44
波兰公司职员的人均月收入在一千欧元的样子,要比西欧穷很多,但是比中国还是要
富裕.
http://news-poland.com/result/news/id/939
An average Polish salary in companies is one thousad Euro. It's still not
even a minimum level of salaries in Western Europe - informed "
Rzeczpospolita".
Average salaries in Poland increase several percent a year. Such tendency,
accoding to economists, will remain till the end of the year. By the strong
zloty currency it means that calcualted as per the exchange rate of Euro,
our salaries in companies oscillate
t*******h
发帖数: 2882
45
http://www.outlookindia.com/article.aspx?270223
The Great Claw of China
The confessions of NSCN(IM) leader Anthony Shimray show exactly how China is
fuelling India’s northeastern insurgencies
Saikat Datta
Wooing NSCN (IM)
*China agrees to host a permanent representative of the NSCN (IM) from 2008
*The outfit is asked to spy on Indian troops in Arunachal Pradesh and the
Dalai Lama
*Pakistan’s ISI also contacts NSCN (IM) and asks it to break the ceasefire
with India
*NSCN (IM)’s firepower grows si... 阅读全帖
g****t
发帖数: 31659
46
你这都什么胡说八道阿......
你这个1:7.8, 20%都是稳态分析。换句话说,那都是假设各种无限大无限小条件下把
微分方程弄成代数方程的结果。
但具体金融操作中,没谁不考虑动态过程的。道理很简单:
例如我今天加印1倍的美元,市场上
美元显然不会立即贬值一倍的,这需要一个动态过程,最后才能到贬值一倍这个点。
就算没有俄罗斯的default,
照样会有稳态之前的oscillation,你的钱能不能cover住暂态过程,这是最难处理的问
题。
这种任何地方都存在,而不是你所谓的谁眼光正确,但是钱不够时间不够那么简单。
t*******h
发帖数: 2882
47
来自主题: Military版 - 解放广场上的中国天气
大意:
世界粮农组织警告,中国干旱将迫使世界最大小麦生产者(中国)大量进口谷物,使得
市场价格创纪录的攀升。
埃及起义的根本原因,是中国:亚洲的繁荣造成了对谷物的空前需求。
40%的埃及人每天生活费低于2刀--甚至比加沙地带的人害穷。
食品的上涨加重了埃及人对现政权的不满。
埃及不能像中国在1949年一样搞土改,一切已经太晚了。
http://www.atimes.com/atimes/Middle_East/MB10Ak02.html
Chinese weather on Tahrir Square
By Spengler
The late novelist James Clavell had a tiresome habit of driving the plots of
his potboilers into cul-de-sacs, whence he would extricate them with a
natural disaster.
Egypt had its Clavell moment on February 8 when the Food and Agricul... 阅读全帖
a***r
发帖数: 594
48
美国的划分也是这样的。比如:
MIT 物理系的“核物理实验室”涵盖该系的理论物理中心:
http://web.mit.edu/lns/research/index.html
research interests: anti-matter, neutrino physics, dark matter, structure of
proton, structure of high density matter and early universe.
Research on neutrino oscillation (standard and slightly beyong standard
model physics), protron structure (asymptotic and none asymptotic QCD) and
high density matter (heavy ion collider) are loosely considered topics of
modern nuclear physics.
MIT 的核工程系。
http://web.mit.... 阅读全帖
S*********y
发帖数: 481
49
Will the US Really Experience a Violent Upheaval in 2020?
By Natalie Wolchover | LiveScience.com
Circa 1870, the North fought the South in the Civil War. Half a century
later, around 1920, worker unrest, racial tensions and anti-Communist
sentiment caused another nationwide upsurge of violence. Then, 50 years
later, the Vietnam War and Civil Rights Movement triggered a third peak in
violent political, social and racial conflict. Fifty years after that will
be 2020. If history continues to repeat... 阅读全帖
m**********e
发帖数: 12525
50
你看看人家搞oscillator network的给的结果,中等规模的grid,相位精度
至少要在10^-5量级,不然就进入非线性发散振荡:
http://motion.me.ucsb.edu/pdf/2011v-dcb-pnas.pdf
大规模的国家电网,都是要达到nano second的精度的
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