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1 November 2026
- 15:0615:06, 1 November 2026 diff hist +1,093 N Assignment 3, Fall 2026 Created page with "Held-Hou(1980) 讨论了当外部强迫的经向分布呈二次勒让德多项式,即<math>\dfrac{\Theta_E(\phi,z)}{\Theta_o}=1-\dfrac{2}{3}\Delta_H P_2(\sin \phi)+\Delta_v(\dfrac{z}{H}-\dfrac{1}{2})</math>的情况下,哈德莱环流内的风场、温度场、环流的空间范围等将怎样随纬度和外力强迫的强度而变化。 如果将外力强迫的空间分布改为<math>\dfrac{\Theta_E(\phi,z)}{\Theta_o}=1-\Delta_H(\sin^3 \phi - \dfrac{1}{4})+\Delta_v..." current
- 15:0515:05, 1 November 2026 diff hist +58 General Circulation(Fall 2026) →Assignments current
11 October 2026
- 05:1005:10, 11 October 2026 diff hist 0 Assignment 2, Fall 2026 No edit summary current
- 04:2704:27, 11 October 2026 diff hist +2,706 N Assignment 2, Fall 2026 Created page with "<font color="red" size="2">请在题目一和题目二中任选一题作为本章的作业题目。另外的一题可作为选做题。</font> ==Question 1== 在第二章中,我们学习了Budyko的能量平衡气候模型(Simple Energy Balance Climate Model),并用此模型来讨论了存在冰雪线的情况下,气候系统的稳定性问题。冰雪线的南北移动会引起行星反照率及热量的动力输送的变化。我们发现这两种过程的..."
- 04:2604:26, 11 October 2026 diff hist +81 General Circulation(Fall 2026) →Assignments
30 September 2026
- 00:4300:43, 30 September 2026 diff hist +1 General Circulation(Fall 2026) No edit summary
28 September 2026
27 September 2026
- 08:1608:16, 27 September 2026 diff hist 0 General Circulation(Fall 2026) No edit summary
- 08:1308:13, 27 September 2026 diff hist +30 Assignment 1, Fall 2026 →Bonus Question current
- 08:1108:11, 27 September 2026 diff hist −8 Assignment 1, Fall 2026 No edit summary
- 08:0908:09, 27 September 2026 diff hist +3,036 N Assignment 1, Fall 2026 Created page with "==Question #1== 请使用多年(>20年)的NCEP/NCAR(或其他标明的)月平均再分析资料,画出各季节(至少画出冬夏两季)纬向平均温度场、纬向平均纬向风场的高度-纬度剖面分布,并简述其分布特征和季节变化特征。 ==Question #2== 请使用多年(>20年)的NCEP/NCAR(或其他标明的)月平均再分析资料,画出各季节(至少画出冬夏两季)温度场、纬向风场在各高度(8..."
- 08:0408:04, 27 September 2026 diff hist +2 General Circulation(Fall 2026) →Announcement
- 08:0208:02, 27 September 2026 diff hist 0 General Circulation(Fall 2026) →Course info
- 08:0208:02, 27 September 2026 diff hist +8,307 N General Circulation(Fall 2026) Created page with "{{Infobox |name = Infobox |bodystyle = |title = 大气环流 <br> General Circulation of the Atmosphere |titlestyle = |headerstyle = background:#ccf; |labelstyle = background:#ddf; |datastyle = |header1 =Instructor |label1 = |data1 = |header2 = |label2 = |data2 = 张洋 |header3 = |label3 = Email |data3 = yangzhang@nju.edu.cn |header4 = |label4= office |data4= 仙林大气楼 B410 |header5 = Class |label5 = |data5 = |hea..."
- 07:5407:54, 27 September 2026 diff hist +1 Main Page →Home Pages for Courses and Seminars current
23 September 2026
20 September 2026
- 05:4105:41, 20 September 2026 diff hist +16,764 N 高级算法 (Fall 2026)/Dimension Reduction Created page with "= Metric Embedding= A '''metric space''' is a pair <math>(X,d)</math>, where <math>X</math> is a set and <math>d</math> is a '''metric''' (or '''distance''') on <math>X</math>, i.e., a function :<math>d:X^2\to\mathbb{R}_{\ge 0}</math> such that for any <math>x,y,z\in X</math>, the following axioms hold: # (identity of indiscernibles) <math>d(x,y)=0\Leftrightarrow x=y</math> # (symmetry) <math>d(x,y)=d(y,x)</math> # (triangle inequality) <math>d(x,z)\le d(x,y)+d(y,z)</ma..."
- 05:4005:40, 20 September 2026 diff hist +298 高级算法 (Fall 2026) →Lecture Notes
16 September 2026
- 15:3315:33, 16 September 2026 diff hist −4 高级算法 (Fall 2026) →Lecture Notes
- 15:3215:32, 16 September 2026 diff hist +251 高级算法 (Fall 2026) →Lecture Notes
15 September 2026
- 12:0012:00, 15 September 2026 diff hist +10,715 N 高级算法 (Fall 2026)/Conditional expectations Created page with "= Conditional Expectations = The '''conditional expectation''' of a random variable <math>Y</math> with respect to an event <math>\mathcal{E}</math> is defined by :<math> \mathbf{E}[Y\mid \mathcal{E}]=\sum_{y}y\Pr[Y=y\mid\mathcal{E}]. </math> In particular, if the event <math>\mathcal{E}</math> is <math>X=a</math>, the conditional expectation :<math> \mathbf{E}[Y\mid X=a] </math> defines a function :<math> f(a)=\mathbf{E}[Y\mid X=a]. </math> Thus, <math>\mathbf{E}[Y\mid..." current
- 11:5911:59, 15 September 2026 diff hist +41,013 N 高级算法 (Fall 2026)/Concentration of measure Created page with "=Chernoff Bound= Suppose that we have a fair coin. If we toss it once, then the outcome is completely unpredictable. But if we toss it, say for 1000 times, then the number of HEADs is very likely to be around 500. This phenomenon, as illustrated in the following figure, is called the '''concentration''' of measure. The Chernoff bound is an inequality that characterizes the concentration phenomenon for the sum of independent trials. File:Coinflip.png|border|450px|cent..." current
- 11:5911:59, 15 September 2026 diff hist +165 高级算法 (Fall 2026) →Lecture Notes
9 September 2026
- 08:3008:30, 9 September 2026 diff hist +81 高级算法 (Fall 2026) →Lecture Notes
- 08:2908:29, 9 September 2026 diff hist +1 高级算法 (Fall 2026) →Lecture Notes
- 04:4404:44, 9 September 2026 diff hist 0 高级算法 (Fall 2026) →Lecture Notes Tag: Manual revert
- 04:4304:43, 9 September 2026 diff hist +1 高级算法 (Fall 2026) →Lecture Notes Tag: Reverted
- 04:4304:43, 9 September 2026 diff hist 0 File:Hashing-26.pdf Etone uploaded a new version of File:Hashing-26.pdf current
- 04:4204:42, 9 September 2026 diff hist −1 高级算法 (Fall 2026) →Lecture Notes Tag: Reverted
8 September 2026
- 13:5413:54, 8 September 2026 diff hist +114 高级算法 (Fall 2026) →Lecture Notes
- 13:5313:53, 8 September 2026 diff hist 0 N File:AA26-note-hashing-zh.pdf No edit summary current
- 13:5313:53, 8 September 2026 diff hist 0 N File:AA26-note-hashing-en.pdf No edit summary current
- 13:5213:52, 8 September 2026 diff hist +31 高级算法 (Fall 2026) →Lecture Notes
- 13:4713:47, 8 September 2026 diff hist 0 N File:Hashing-26.pdf No edit summary
- 13:4613:46, 8 September 2026 diff hist 0 N File:Hashing.pdf No edit summary current
7 September 2026
- 10:1310:13, 7 September 2026 diff hist +5,755 N 高级算法 (Fall 2026)/Basic deviation inequalities Created page with "=Markov's Inequality= One of the most natural information about a random variable is its expectation, which is the first moment of the random variable. Markov's inequality draws a tail bound for a random variable from its expectation. {{Theorem |Theorem (Markov's Inequality)| :Let <math>X</math> be a random variable assuming only nonnegative values. Then, for all <math>t>0</math>, ::<math>\begin{align} \Pr[X\ge t]\le \frac{\mathbf{E}[X]}{t}. \end{align}</math> }} {{Proo..." current
- 10:1310:13, 7 September 2026 diff hist +15,812 N 高级算法 (Fall 2026)/Limited independence Created page with "= <math>k</math>-wise independence = Recall the definition of independence between events: {{Theorem |Definition (Independent events)| :Events <math>\mathcal{E}_1, \mathcal{E}_2, \ldots, \mathcal{E}_n</math> are '''mutually independent''' if, for any subset <math>I\subseteq\{1,2,\ldots,n\}</math>, ::<math>\begin{align} \Pr\left[\bigwedge_{i\in I}\mathcal{E}_i\right] &= \prod_{i\in I}\Pr[\mathcal{E}_i]. \end{align}</math> }} Similarly, we can define independence between..." current
- 10:1210:12, 7 September 2026 diff hist +49,292 N 高级算法 (Fall 2026)/Hashing and Sketching Created page with "=Balls into Bins= The following is the so-called balls into bins model. Consider throwing <math>m</math> balls into <math>n</math> bins uniformly and independently at random. This is equivalent to a random mapping <math>f:[m]\to[n]</math>. Needless to say, random mapping is an important random model and may have many applications in Computer Science, e.g. hashing. We are concerned with the following three questions regarding the balls into bins model: * birthday problem..." current
- 10:1210:12, 7 September 2026 diff hist +245 高级算法 (Fall 2026) →Lecture Notes
2 September 2026
- 16:0316:03, 2 September 2026 diff hist −1 高级算法 (Fall 2026)/Fingerprinting →Freivalds Algorithm current
- 16:0116:01, 2 September 2026 diff hist +347 高级算法 (Fall 2026) →Lecture Notes
- 09:1909:19, 2 September 2026 diff hist −2 高级算法 (Fall 2026) →Lecture Notes
- 09:1909:19, 2 September 2026 diff hist +6,210 N 高级算法 (Fall 2026)/Finite Field Basics Created page with "=Field= Let <math>S</math> be a set, '''closed''' under binary operations <math>+</math> (addition) and <math>\cdot</math> (multiplication). It gives us the following algebraic structures if the corresponding set of axioms are satisfied. {|class="wikitable" !colspan="7"|Structures !Axioms !Operations |- |rowspan="9" style="background-color:#ffffcc;text-align:center;"|'''''field''''' |rowspan="8" style="background-color:#ffffcc;text-align:center;"|'''''commutative<br>rin..." current
- 09:1809:18, 2 September 2026 diff hist +38,283 N 高级算法 (Fall 2026)/Fingerprinting Created page with "= Checking Matrix Multiplication= thumb|360px|right|The evolution of time complexity <math>O(n^{\omega})</math> for matrix multiplication. Let <math>\mathbb{F}</math> be a feild (you may think of it as the filed <math>\mathbb{Q}</math> of rational numbers, or the finite field <math>\mathbb{Z}_p</math> of integers modulo prime <math>p</math>). We suppose that each field operation (addition, subtraction, multiplication, division) has u..."
- 09:1809:18, 2 September 2026 diff hist +228 高级算法 (Fall 2026) →Lecture Notes
17 June 2026
- 04:0504:05, 17 June 2026 diff hist +34,076 N 组合数学 (Fall 2026)/Matching theory Created page with "== Systems of Distinct Representatives (SDR)== A '''system of distinct representatives (SDR)''' (also called a '''transversal''') for a sequence of (not necessarily distinct) sets <math>S_1,S_2,\ldots,S_m</math> is a sequence of <font color=red>''distinct''</font> elements <math>x_1,x_2,\ldots,x_m</math> such that <math>x_i\in S_i</math> for all <math>i=1,2,\ldots,m</math>. === Hall's marriage theorem === If the sets <math>S_1,S_2,\ldots,S_m</math> have a system of dist..." current
- 04:0404:04, 17 June 2026 diff hist +141 组合数学 (Spring 2026) →Lecture Notes
20 May 2026
- 13:3313:33, 20 May 2026 diff hist +26,029 N 组合数学 (Fall 2026)/Ramsey theory Created page with "== Ramsey's Theorem == === Ramsey's theorem for graph === {{Theorem|Ramsey's Theorem| :Let <math>k,\ell</math> be positive integers. Then there exists an integer <math>R(k,\ell)</math> satisfying: :If <math>n\ge R(k,\ell)</math>, for any coloring of edges of <math>K_n</math> with two colors red and blue, there exists a red <math>K_k</math> or a blue <math>K_\ell</math>. }} {{Proof| We show that <math>R(k,\ell)</math> is finite by induction on <math>k+\ell</math>. For the..." current
- 13:3213:32, 20 May 2026 diff hist +137 组合数学 (Spring 2026) →Lecture Notes
13 May 2026
- 08:4908:49, 13 May 2026 diff hist +51,460 N 组合数学 (Fall 2026)/Extremal set theory Created page with "== Sunflowers == An set system is a '''sunflower''' if all its member sets intersect at the same set of elements. {{Theorem|Definition (sunflower)| : A set family <math>\mathcal{F}\subseteq 2^X</math> is a '''sunflower''' of size <math>r</math> with a '''core''' <math>C\subseteq X</math> if ::<math>\forall S,T\in\mathcal{F}</math> that <math>S\neq T</math>, <math>S\cap T=C</math>. }} Note that we do not require the core to be nonempty, thus a family of disjoint sets is..." current