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to simply think of (G, ◦) as the fixed graph G. So, for example, Zd is a ‘random’ rooted graph with root at the origin. Let Gn be a sequence of finite connected graphs of maximum degree at most ∆. Let ◦n denote a uniform random vertex of Gn. We say Gn converges in the local weak limit if the law of the random rooted grap...
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(mod n) for exactly one i and xi = yi for all other i. Exercise 2.2. Suppose the graphs Gn have maximum degree at most ∆ and converge in the local weak limit to (G, ◦). Show that ges in distribution (as integer valued random variables) to deg(◦). Conclude that E deg(◦n) → E deg(◦) (cid:3). (cid:2) deg(◦n (cid:3) ) conv...
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), (G(cid:48), ◦(cid:48)) on (Ω, Σ, µ) such that (Gn, ◦n) has the law of (G(cid:48) If Gn converges to (G, ◦) then there is a probability space (Ω, Σ, µ) and G-valued random variables n, ◦(cid:48) (G(cid:48) n), (G, ◦) has the law of (G, ◦), n) ∼= Nr(G(cid:48), ◦(cid:48))) → 1 as n → ∞. This common and for every r ≥ 0 ...
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:48) k/2(G n) (cid:29) Nk/2(G(cid:48), ◦(cid:48)) (cid:3) −→ 0 n, ◦(cid:48) n) (cid:29) Nk/2(G(cid:48), ◦(cid:48)) as n → ∞ . (cid:12) (cid:3)(cid:12) (cid:12) 2.2. Local weak limit of random regular graphs. In this section we will show a classical result that random d-regular graphs converge to the d-regular tree Td i...
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showed that as n → ∞, P(cid:2) Gn,d is simple (cid:3) → 1− 2d e 4 . Also, conditioned on Gn,d being simple its distribution is a uniform random d-regular graph on It follows from these observations that any sequence of graph properties An whose n vertices. probability under Gn,d tends to 1 as n → ∞ also tends to 1 unde...
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of length at most 2r. It follows from this where C 2r is the ≤ (cid:3) (cid:2) wing lemma argument that (cid:2) E |v ∈ V (Gn,d) : Nr(Gn,d, v) = Nr(Td, ◦)| ≤ 2rdrE C (cid:2) , E if d ≥ 3, and more precisely (cid:3) ≤ 2r(3d − 3) shows that E C follo ∼ 2r (cid:2) ≤2r (cid:3) ≤2r . The (cid:3) C≤2 r erges to converges to a...
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{ conclude that (cid:2) (cid:3) E C(cid:96) = (cid:88) {v1 ,...,v(cid:96)} (cid:2) P {v1, . . . , v(cid:96)} forms an (cid:96) − cycle = (cid:3) (cid:18) (cid:19) n ((cid:96) (cid:96) − 1)!(d(d − 2(nd 1))(cid:96)(nd − 1)!! − − 2(cid:96) 1)!! . Note that (cid:0)n(cid:1) ≤ n(cid:96)/(cid:96)!, and in fact if (cid:96) is ...
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to express log sptr(G |Gn| return probabilities of the SRW on (G, ◦). In particular, we shall see that lim n→∞ log sptr(Gn) |Gn| (cid:104) = E log deg(◦) − (cid:88) pk G(◦) (cid:105) . k k≥1 The quantity of the r.h.s. is called the tree entropy of (G, ◦). If the limiting graph G is deterministic and vertex transitive, ...
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) = 1 (cid:80) 2 (x,y)(f (x) − f (y))(g(x) x∼y − g y)). ( (2) L is self-adjoint and positive semi-definite: (Lf, g) = (f, Lg) and (Lf, f ) ≥ 0 for all f, g. (3) Lf = 0 if and only if f is constant on the connected components of f . (4) The dimension of the eigenspace of L corresponding to eigenvalue 0 equals the number ...
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of its roots, which are the eigenvaluesof L, then we can deduce that the coefficient of t is − (cid:80) (cid:81) Exercise 3.2. Let G be a connected finite graph and suppose {x, y} is an edge of G. Let G \ {x, y} be the graph obtained from removing the edge {x, y} from G. Let G · {x, y} be the graph obtained from contracti...
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V (G){|f (x)|}. If G is connected then the largest eigenvalue of P is 1 and it has multiplicity 1 as well. The eigenfuctions for the eigenvalue 1 are constant functions over V (G). Suppose that ∞ ∞ ∈ −1 ≤ µ1 ≤ µ2 ≤ · · · ≤ µn 1 < µn = 1 are the n eigenvalues of P . If e is the number of edges in G − then we may rewrite...
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:80) k≥1 (4) log sptr(G) |G| = log 2e n (G) + (cid:80) ∈ (G) log deg(x) x V n − (cid:88) 1 ( k k≥1 (cid:80) k x∈V (G) pG(x)) − 1 . n Theorem 3.3. Let Gn be a sequence of finite, connected graphs with maximum degree bounded by ∆ and |Gn| → ∞. Suppose that Gn converges in the local weak limit to a random rooted graph (G, ...
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converges to 0. Also, deg(◦n) converges in distribution to the degree deg(◦) of (G, ◦) (exercise 2.2). (cid:3) → log x is The function x (cid:3) (cid:2) converges to E log deg(◦) . Following the discussion is Section 2.1 we conclude that E pk G(◦) (cid:3) as well. To conclude the proof it suffices to show that |Gn|−1 con...
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+ 1)1/4 . (cid:80) V (G). Let (f, g)π = x V (G) π(x)f (x)g(x) for Proof. The vector π is a probability ∈ f, g ∈ RV (G). Let P denote the transition matrix of the SRW on G; thus, G(x) = P k(x, x). Note pk that π(x)P (x, y) = 1x y/(2e) = π(y)P (y, x). From this we conclude that (P f, g)π = (f, P g)π. Let measure on ∼ LO...
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positive and negative values. Apply the inequality above to the function sgn(f )f 2 and use the inequality |sgn(s)s2 − sgn(t)t2| ≤ |s − t|(|s| + |t|) to |(|f (x)| + |f ( )|)(cid:3). Straightforward calculations conclude that ||f ||2 ≤ e (cid:80) show that (x,y) K(x, y)(cid:2)|f (x) − f (y) ∞ y K(x, y)|f (x) − f (y)|2 =...
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)P mf, P m f (cid:1) π (cid:0) = 2e2 (P 2m (cid:1) − P 2m+1)f, f . Since ||P g|| ≤ ||g|| ∞ ∞ , if we sum the inequality abo ve over 0 ≤ m ≤ k we get (k + 1)||P kf ||4 ≤ 2e2 (cid:88) ∞ k m=0 ||P mf || ≤ 2e2(cid:0)(I − P 2k+1)f, f ∞ (cid:1) 2 π ≤ 2e . last inequalit y holds because every eigenvalue of I − P m lies in the...
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(x)−1(1 − π(x))(k + 1)−1/4. However, π(x)−1 = 2e/deg(x) P k(x,x) − 1(cid:12) π(x) (cid:12) (cid:12) (cid:12) the degrees in G we have that 2e ≤ ∆n, and this establishes the statement in the lemma. 1. Thus, we conclude that P k(x,x) π(x) − 1 ≤ 2e (cid:12) (cid:12) (cid:12) ≤ 2e(k + 1)−1/4. As 2e equals the sum of Lemma ...
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. We begin to calculate the tree entropy of a graph we have to be . In order d and Zd Consider the generating function F (t) = k 0 pk (◦)tk. Actually note that pk ( Td ≥ odd because whenever the SRW takes a step along an edge that moves it away from the root it ◦) = 0 k is Td if with the d-regular tree Td. (cid:80) mus...
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A rigorous calculation of the tree entropy of Zd requires an excursion into operator theory that is outside the scope of these notes. We will sketch the argument; for details see Lyons [5] Section 4 or , λn−1 are the Lyons [6]. Recall the Matrix-Tree Theorem for finite graphs which states that if λ1, . . . (cid:80) n 1 ...
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xi)). As the Fourier transform preserves inner products we get that ∈ ˆ ˆ (cid:126) (cid:126) (cid:90) h(Zd) = (cid:16) log 2d − 2 [0,1]d d (cid:88) i=1 cos(2πxi) (cid:17) dx. 4. Open problems One can consider the space of (isomorphism classes of) doubly rooted graphs (G, x, y) of bounded degree, analogous to the space...
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of finite connected graphs is unimodular. It is not known whether the converse is true: is a unimodular random rooted graph (G, ◦) a local weak limit of finite connected graphs. This is known to be true for unimodular trees (see Aldous and Lyons [1]). This is a major open problem in the field. Here is a problem on tree en...
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14 (2005), pp. 491–522. [6] R. Lyons, Identities and inequalities for tree entropy, Combin. Probab. Comput. 19 (2010), pp. 303-313. [7] R. Lyons and Y. Peres, Probability on Trees and Networks, Cambridge University Press, 2014, in preparation. Current version available at http://mypage.iu.edu/~rdlyons/. [8] B. D. McKay...
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Lecture 13 8.324 Relativistic Quantum Field Theory II Fall 2010 8.324 Relativistic Quantum Field Theory II MIT OpenCourseWare Lecture Notes Hong Liu, Fall 2010 Lecture 13 We continue our analysis of renormalization in quantum electrodynamics from last lecture. 3.1.4: Charge Renormalization Consider the vertex co...
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2W δ ¯ η�(x)δη� (y2) − δ(4)(x − y2) δ2W δη¯�(y1)δη� (x) ] , J=α=α¯=0 or, equivalently, 1 ∂2∂µ ⟨0 T (Aµ(0)ψ�(y1)ψ¯ ξ | | � (y2)) [ 0⟩ = eB δ(4)(x − y1) ⟨0 T (ψ�(x)ψ¯ | � (y2)) 0⟩ − δ(4)(x − y2) ⟨0 T (ψ�(y1)ψ¯ | | � (x)) (4) ] | 0⟩ . −→ iqµ , where qµ ≡ (k2 − k1)µ. We can set x = 0 by applying (5) Changing...
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also close to on-shell. Then = k, k on-shell and 1 S−1(k1) ≈ − (ik/1 + m − iϵ) + . . . Z 2 1 S−1(k2) ≈ − (ik/2 + m − iϵ) + . . . Z 2 1 (6) (7) (8) Lecture 13 8.324 Relativistic Quantum Field Theory II Fall 2010 where m here is the physical mass. We then have or qδ Γδ (k, k) = − eB i/q, Z2 Γδ (k, ...
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≡ DB SB ΓB SB and G(phys) = DSΓ(phys)S. From this, we have that √ Γδ (k, k) = Z3Z2Γδ B (k, k) (9) (10) (11) (12) (13) (14) (15) (16) and so √ e = Z3eB . The dependence of e on Z2 cancels precisely as a result of ΓB ∝ strength renormalization of the photon, has important implications: the ratio is universa...
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δη(x2) . . . , and then setting Jµ = η¯ = η = 0. The resulting expression is most transparently written diagramatically in momentum space: pr . . . p2 p1 kµ qn . . . q2 q1 ∑    i = eB pr . .. p2 p1 pr qn   . . . . . .   qi − k  −  pi + k . . . . . . p1 q1 2   ...
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photon lines or any other neutral particles (if they exist) can be off-shell, since they they do not transform under gauge transformations. For Ward identities to be valid, regularization should preserve gauge invariance. 3 MIT OpenCourseWare http://ocw.mit.edu 8.324 Relativistic Quantum Field Theory II Fall 201...
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ESD 342 Session 3 Faculty: Magee, Moses, Whitney February 14, 2006 Professor C. Magee, 2006 Page 1 Point of View & Biases Presentations • Reverse Alphabetical Order: Please write down or remember who you follow and come to the front as soon as that person finishes or as soon as the moderator declares that their 3 m...
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” Project Ideas • Continue one of last year’s projects-see web site • Improve detail of Western Power Grid or some other part of the electric power grid • Analyze a software system or a language over time • Build and analyze a collection of social network data and its time • • dependence Investigate and model the old...
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Engineering Systems Engineering Systems Engineering Systems Engineering Systems Doctoral Seminar Doctoral Seminar Fall 2011 ESD 83 –– Fall 2011 ESD.83 Fall 2011 ESD 83 ESD.83 Fall 2011 Session 6 Faculty: Chris Magee and Joe Sussman TA: Rebecca Kaarina Saari Guest: Professor Stuart Kauffman Guest: Professor ...
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normal distributions..and some not likely to be normal © 2007 Chris Magee, Engineering Systems Division, Massachusetts Institute of Technology 3 ) % ( e g a t n e c r e P 6 4 2 0 4 3 2 1 0 0 50 100 150 200 250 0 20 40 60 80 100 120 Heights of Males Speeds of Cars Histogram of heights in centimeters of American males...
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th  Histograms  Normal (and nearly so)  Skewed (and heavily skewed)  Reasons for normal vs. skewed?  Power law (skewed) p k ~ k  Why power laws?  Why power laws? © 2007 Chris Magee, Engineering Systems Division, Massachusetts Institute of Technology 6 Power laws are ubiquitous Low variability Ga...
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Development of quantitative model 3. Observe (system) ) ( y  Design a specific version of a known procedure  Develop a new observational procedure  Find, and/or extract and combine data  Find and/or extract and combine data 4. Analyze observations  Use existing models to “reduce” data to model-relevant  D...
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 As you think to solve the following puzzle, observe your thoughts to the best of observe your thoughts to the best of your ability  “One morning, exactly at sunrise, a Buddhist monk began to climb a tall mountain. The narrow path, no more than a foot or two wide, spiraled around the mountain to a glittering te...
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ignore some facts? g y  “Glittering” temple, dried fruit, spiral path?  Did you use other mental operations to explore the problem? the problem?  Rotation or “superimposition”, mathematical derivation, logical rules  How difficult was it to observe your own  ” “ thinking?  Very difficult and ambiguous © ...
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 H ibl i b fl i h L thinking?  How might we be more flexible in our  H ibl i i ht b fl thinking operations?  Flexibility in Thinking Representations  Flexibility in Thinking Representations is essential to flexibility in operations  see McKim s book -Thinking Visually and  see McKim’s book Thi...
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Chernoff faces: Eric W. Weisstein. "Chernoff Face." From MathWorld--A Wolfram Web Resource. http://mathworld.wolfram.com/ChernoffFace.html Image by MIT OpenCourseWare. © 2008 Chris Magee, Engineering Systems Division, Massachusetts Institute of Technology 22 Examples of Visual Representation & Application to Comple...
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� Present many numbers in small space  Present many numbers in small space  Make large data sets coherent  Encourage the eye to compare different p g y pieces of data  Reveal several levels of data detail  Serve a relatively clear purpose  Serve a relatively clear purpose (description, exploration, tabulatio...
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2008 Chris Magee, Engineering Systems Division, Massachusetts Institute of Technology 32 Comparative Map abstractions and scale-Subway Systems and scale-Subway Systems scale: 1 km = 7 pixels QTIar 1 km are needed to see this QuickTime™ and TIFF (Uncompressed) de 1 mi http://www.fakeisthenewreal.org/subway/index....
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20 18 16 14 12 10 8 6 4 2 0 1 9 5 2 1 9 5 4 1 9 5 6 1 9 5 8 1 9 6 0 1 9 6 2 1 9 6 4 1 9 6 6 1 9 6 8 1 9 7 0 1 9 7 2 1 9 7 4 1 9 7 6 1 9 5 2 1 9 5 4 1 9 5 6 1 9 5 8 1 9 6 0 1 9 6 2 1 9 6 4 1 9 6 6 1 9 6 8 1 9 7 0 1 9 7 2 1 9 7 4 1 9 7 6 Year Investment differential (JP-US) Military differential (US-JP) Year Investment d...
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37 Small multiples (Tufte) Small multiples (Tufte) Image removed due to copyright restrictions. © 2008 Chris Magee, Engineering Systems Division, Massachusetts Institute of Technology 38 Choice of Representation Choice of Representation “The form of a representation cannot be divorced from its ...
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f b ildi  Form basis for building skill at Systems  F Representation and Data Visualization  Maps, graphs, matrices, lists, sketches, pictures,  What to think about in choosing representations  What to think about in choosing representations  Understand some basic human capabilities kill t S t  Exami...
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6.864: Lecture 3 (September 15, 2005) Smoothed Estimation, and Language Modeling Overview • The language modeling problem • Smoothed “n-gram” estimates The Language Modeling Problem • We have some vocabulary, say V = {the, a, man, telescope, Beckham, two, . . .} • We have an (infinite) set of strings, V � the a t...
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P (w3 | START, w1, w2) ×P (w4 | START, w1, w2, w3) . . . ×P (wn | START, w1, w2, . . . , wn−1) ×P (STOP | START, w1, w2, . . . , wn−1, wn) For Example P (the, dog, laughs) = P (the | START) ×P (dog | START, the) ×P (laughs | START, the, dog) ×P (STOP | START, the, dog, laughs) Deriving a Trigram Probability Mode...
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look at the probability under our model Or more conveniently, the log probability n log P (Si) = ⎧ i=1 n � i=1 log P (Si) n i=1 P (Si). ⎩ • In fact the usual evaluation measure is perplexity Perplexity = 2−x where x = n1 � W i=1 log P (Si) and W is the total number of words in the test data. Some I...
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nor (2) (nor indeed any part of these sentences) has ever occurred in an English discourse. Hence, in any statistical model for grammaticalness, these sentences will be ruled out on identical grounds as equally ‘remote’ from English. Yet (1), though nonsensical, is grammatical, while (2) is not. . . . (my emphasis...
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(wi | wi−2, wi−1) +�2 × PM L(wi | wi−1) +�3 × PM L(wi) where �1 + �2 + �3 = 1, and �i � 0 for all i. • Our estimate correctly defines a distribution: Pˆ(w | wi−2, wi−1) w�V ⎨ = ⎨ = �1 w ⎨ = �1 + �2 + �3 w�V [�1 × PM L(w | wi−2 , wi−1) + �2 × PM L (w | wi−1) + �3 × PM L(w)] PM L (w | wi−2, wi−1) + �2 w PM L (...
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Iterative Method Initialization: Pick arbitrary/random values for �1, �2, �3. Step 1: Calculate the following quantities: c1 = c2 = c3 = � w1 ,w2 ,w3 �V � w1 ,w2 ,w3 �V � w1 ,w2 ,w3 �V Count2 (w1, w2, w3)�1PM L(w3 | w1, w2) �1PM L(w3 | w1 , w2) + �2PM L(w3 | w2) + �3PM L(w3) Count2 (w1 , w2, w3 )�2PM L(w3 | w2 ) ...
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�’s on the partition: Pˆ(wi | wi−2, wi−1) = ��(wi−2,wi−1) × PM L(wi | wi−2, wi−1) +��(wi−2,wi−1) +��(wi−2,wi−1) × PM L(wi | wi−1) × PM L(wi) 1 2 3 where ��(wi−2 ,wi−1 ) 2 1 ��(wi−2,wi−1) � 0 for all i. i + ��(wi−2 ,wi−1 ) + ��(wi−2,wi−1) 3 = 1, and • Our estimate correctly defines a distribution: ...
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1) = �1 × PM L(wi | wi−2, wi−1) +(1 − �1)[�2 × PM L(wi | wi−1) +(1 − �2) × PM L(wi)] where 0 � �11, and 0 � �2 � 1. • Next, define �1 = Count(wi−2, wi−1) � + Count(wi−2, wi−1) �2 = Count(wi−1) � + Count(wi−1) where � is a parameter chosen to optimize probability of a development set. An Alternative Definitio...
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1/48 1/48 (particularly for low count items) Discounting Methods • Now define “discounted” counts, for example (a first, simple definition): Count�(x) = Count(x) − 0.5 • New estimates: x the the, dog the, woman the, man the, park the, job the, telescope the, manual the, afternoon the, country the, street...
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� PM L(wi) w�B(wi−1) PM L(w) If wi � B(wi−1) � � � � � � � � ⎪ PKAT Z (wi | wi−1) = where �(wi−1) = 1 − Count�(wi−1, w) � w�A(wi−1) Count(wi−1) Katz Back-Off Models (Trigrams) • For a trigram model, first define two sets A(wi−2, wi−1) = {w : Count(wi−2, wi−1, w) > 0} B(wi−2, wi−1) = {w : Count(w...
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were needed within the Enigma code-breaking effort. • Define nr = number of elements x for which Count(x) = r. • Modified count for any x with Count(x) = r and r > 0: (r + 1) nr+1 nr • Leads to the following estimate of “missing mass”: n1 N where N is the size of the sample. This is the estimate of the probabil...
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DT NN NP ∈ NP PP NP PP ∈ P 1.0 0.4 0.4 0.2 0.3 0.7 1.0 Vi ∈ sleeps Vt ∈ saw NN ∈ man NN ∈ woman NN ∈ DT ∈ IN ∈ with IN ∈ 1.0 1.0 0.7 0.2 telescope 0.1 1.0 the 0.5 0.5 in • Probability of a tree with rules �i ≥ �i is i P (�i ≥ �i|�i) ⎩ DERIVATION S NP VP DT N VP the N VP the dog VP ...
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of example trees. • If the training data is generated by a PCFG, then as the training data size goes to infinity, the maximum-likelihood PCFG will converge to the same distribution as the “true” PCFG. PCFGs Booth and Thompson (73) showed that a CFG with rule probabilities correctly defines a distribution over the s...
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ation: n = number of words in the sentence Nk for k = 1 . . . K is k’th non-terminal N1 = S (the start symbol) w.l.g., • Define a dynamic programming table λ[i, j, k] = maximum probability of a constituent with non-terminal Nk spanning words i . . . j inclusive • Our goal is to calculate maxT �T (S) P (T, S) = λ...
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NlNm is in the grammar prob ≤ P (Nk ≥ NlNm) × λ[i, s, l] × λ[s + 1, j, m] If prob > max max ≤ prob //Store backpointers which imply the best parse Split(i, j, k) = {s, l, m} λ[i, j, k] = max A Dynamic Programming Algorithm for the Sum • Given a PCFG and a sentence S, how do we find P (T, S) � T �T (S) • Notatio...
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) = 0 if Nk � NlNm is not in the grammar) Initialization: For i = 1 ... n, k = 1 ... K λ[i, i, k] = P (Nk ≥ wi|Nk ) Main Loop: For length = 1 . . . (n − 1), i = 1 . . . (n − 1ength), k = 1 . . . K j ≤ i + length sum ≤ 0 For s = i . . . (j − 1), For Nl, Nm such that Nk ≥ NlNm is in the grammar prob ≤ P (Nk...
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MIT OpenCourseWare http://ocw.mit.edu 6.189 Multicore Programming Primer, January (IAP) 2007 Please use the following citation format: Michael Perrone, 6.189 Multicore Programming Primer, January (IAP) 2007. (Massachusetts Institute of Technology: MIT OpenCourseWare). http://ocw.mit.edu (accessed MM DD, YYYY). Li...
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ventional Bulk CMOS SOI (silicon-on-insulator) High mobility Double-Gate ? Image by MIT OpenCourseWare. 1988 1992 1996 2000 2004 2008 2012 Year Michael Perrone © Copyrights by IBM Corp. and by other(s) 2007 4 6.189 IAP 2007 MIT Power Density – The fundamental p roblem 1000 W/cm2 100 10 1 Nuclea...
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H e l u d o M 14 12 10 8 6 4 2 Steam IRON 5W/cm2 IBM ES9000 Bipolar Fujitsu VP2000 ��IBM 3090S NTT Fujitsu M-780 IBM 3090 Start of Water Cooling Vacuum IBM 360 IBM 370 CDC Cyber 205 IBM 4381 IBM 3081 Fujitsu M380 IBM 3033 0 1950 1960 1970 1980 1990 2000 2010 Year of Announcement Image b...
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© Copyrights by IBM Corp. and by other(s) 2007 8 6.189 IAP 2007 MIT 6.189 IAP 2007 Lecture 2 The Multicore Approach Michael Perrone © Copyrights by IBM Corp. and by other(s) 2007 9 6.189 IAP 2007 MIT Systems and Technology Group Cell Courtesy of International Business Machines Corporation. Una...
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low operating voltage with advanced power management „ Attacks on the “Memory Wall” – Streaming DMA architecture – 3-level Memory Model: Main Storage, Local Storage, Register Files „ Attacks on the “Frequency Wall” – Highly optimized implementation – Large shared register files and software controlled branching t...
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by IBM Corp. and by other(s) 2007 15 6.189 IAP 2007 MIT 6.189 IAP 2007 Lecture 2 Cell Hardware Components Michael Perrone © Copyrights by IBM Corp. and by other(s) 2007 16 6.189 IAP 2007 MIT Cell Chip Courtesy of International Business Machines Corporation. Unauthorized use not permitted. Michael Perrone...
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� „ „ „ „ processor (PowerPC AS 2.0.2) 2-Way hardware multithreaded L1 : 32KB I ; 32KB D L2 : 512KB Coherent load / store VMX-32 Realtime Controls – – Software / hardware managed TLB – Bandwidth / Resource Reservation – Mediated Interrupts Locking L2 Cache & TLB ● Element Interconnect Bus (EIB): „ Four 16...
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I/O access Two queues for DMA commands: Proxy & SPU L o c a l S t o r e A U C S P U M F C L o c a l S t o r e A U C S P U M F C N N 96 Byte/Cycle N N NCU Power Core (PPE) L2 Cache N N MFC AUC SPU Local Store MFC AUC SPU Local Store Element Interconnect Bus N N C F M U P S C U A e r o S t l a c o L C F M...
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a l S t o r e A U C S P U M F C N L o c a l S t o r e A U C S P U M F C N 25 GB/sec XDR DRAM MIC 96 Byte/Cycle NCU Power Core (PPE) L2 Cache Local Store AUC SPU MFC Local Store AUC SPU MFC N N Element Interconnect Bus N N IOIF0 C F M U P S C U A e r o S t l a c o L C F M U P S C U A e r o S t l a c o ...
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16M byte) – I/O Device Identifier per page for LPAR IOST and IOPT Cache – hardware / software managed „ „ L o c a l S t o r e A U C S P U M F C N L o c a l S t o r e A U C S P U M F C N 25 GB/sec XDR DRAM MIC 96 Byte/Cycle NCU Power Core (PPE) L2 Cache IIC IOT N N MFC AUC SPU Local Store MFC AUC SP...
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loading High frequency design High bandwidth for memory and IO accesses Fine tuning for data transfer PU Data Staging via L2 SPU Data Staging Memory Memor PU L2 Memo Memorry PU L2 SPU SPU SPU SPU SPU SPU SPU SPU SPU SPU SPU SPU SPU SPU SPU SPU l oads + 2 pr etch L2 -4 out standingloads +...
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(BE) 6 GFlops (IA32) 12 GFLops (BE) bioinformatic smith-waterman 570 Mcups (IA32) 420 Mcups (per SPE) graphics transform-light 160 MVPS (G5/VMX) 240 MVPS (per SPE) security TRE AES TDES MD-5 SHA-1 communication EEMBC 1.6 fps (G5/VMX) 24 fps (BE) 1.1 Gbps (IA32) 2Gbps (per SPE) 0.12 Gbps (IA32) 0....
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„ Data streaming / throughput support „ Real-time support ● Cell microarchitecture features are exposed to not only its compilers but also its applications „ Performance gains from tuning compilers and applications can be significant Tools/simulators are provided to assist in performance optimization efforts „ Mi...
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.. ƒƒ Finance Finance ƒƒ Trade modeling Trade modeling Med ƒƒ Medical Imagin ical Imaging g ƒƒ CT Scan CT Scan ƒƒ Ultrasound, Ultrasound, …… ƒƒ Industrial Industrial ƒƒ Semiconductor / LCD Semiconductor / LCD ƒƒ Video Conference Video Conference Michael Perrone © Copyrights by IBM Corp. and by other(s) 2007 30 6.189 ...
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„ Cycle accurate SPU simulation (pipeline mode) „ Emitter facility for tracing and viewing simulation events Execution Environment Michael Perrone © Copyrights by IBM Corp. and by other(s) 2007 34 6.189 IAP 2007 MIT SW Stack in Simulation Execution Environment Michael Perrone © Copyrights by IBM Corp. and by o...
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Management Runtime Library (32-bit) std. PPC32 elf interp 32-bit GNU Libs (glibc,etc) ILP32 Processes Library (64-bit) SPE Object Loader Services std. PPC64 elf interp 64-bit GNU Libs (glibc) LP64 Processes System Call Interface exec Loader File System Framework Device Framework Network Framework S...
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Extension Libraries ● Standard SPE C library subset „ „ optimized SPE C99 functions including stdlib c lib, math and etc. subset of POSIX.1 Functions – PPE assisted Execution Environment ● Audio resample - resampling audio signals ● FFT - 1D and 2D fft functions ● gmath - mathematic functions optimized for gamin...
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provided to demonstrate system design constructs ● Complex workloads and demos used to evaluate and demonstrate system performance Terrain Rendering Engine Geometry Engine Execution Environment Physics Simulation Subdivision Surfaces Michael Perrone © Copyrights by IBM Corp. and by other(s) 2007 43 6.189 I...
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pipeline state ● Dynamic analysis (CBE System Simulator) „ Generates statistical data on SPE execution – Cycles, instructions, and CPI – Single/Dual issue rates – Stall statistics – Register usage – Instruction histogram Michael Perrone © Copyrights by IBM Corp. and by other(s) 2007 46 6.189 IAP 2007 MIT Mi...
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Control, PPE Scalar code ● Develop PPE Control, partitioned SPE scalar code „ Communication, synchronization, latency handling ● Transform SPE scalar code to SPE SIMD code ● Re-balance the computation / data movement ● Other optimization considerations „ PPE SIMD, system bottleneck, load balance Michael Perrone ...
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IB 4X IB 4X GbE BladeCenter Network Interface Michael Perrone © Copyrights by IBM Corp. and by other(s) 2007 53 6.189 IAP 2007 MIT Summary ● Cell ushers in a new era of leading edge processors optimized for digital media and entertainment ● Desire for realism is driving a convergence between supercomputin...
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can be used and the results that may be achieved. Actual environmental costs and performance characteristics will vary depending on individual client configurations and conditions. IBM Global Financing offerings are provided through IBM Credit Corporation in the United States and other IBM subsidiaries and divi...
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; Advanced Micro-Partitioning, eServer, Micro-Partitioning, NUMACenter, On Demand Business logo, OpenPower, POWER, Power Architecture, Power Everywhere, Power Family, Power PC, PowerPC Architecture, POWER5, POWER5+, POWER6, POWER6+, Redbooks, System p, System p5, System Storage, VideoCharger, Virtualization Engine. ...
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by other(s) 2007 56 6.189 IAP 2007 MIT (c) Copyright International Business Machines Corporation 2005. All Rights Reserved. Printed in the United Sates April 2005. The following are trademarks of International Business Machines Corporation in the United States, or other countries, or both. IBM IBM Logo Power A...
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DD L O R T N O C GPR LS LS LS LS ● RISC like organization „ 32 bit fixed instructions „ Clean design – unified Register file ● User-mode architecture „ No translation/protection within SPU „ DMA is full Power Arch protect/x-late ● VMX-like SIMD dataflow „ Broad set of operations (8 / 16 / 32 Byte) „ Graph...
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� DMA is full PowerPC protect/xlate D P S F P ● Direct programmer control „ „ DMA/DMA-list Branch hint ● VMX-like SIMD dataflow „ Graphics SP-Float „ No saturate arith, some byte „ IEEE DP-Float (BlueGene-like) ● Unified register file ● 128 entry x 128 bit „ 256KB Local Store „ Combined I & D „ „ 16B/cyc...
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s by IBM Corp. and by other(s) 2007 61 6.189 IAP 2007 MIT SPE Block Diagram Floating-Point Unit Fixed-Point Unit Permute Unit Load-Store Unit Branch Unit Channel Unit Result Forwarding and Staging Register File Local Store (256kB) Single Port SRAM Instruction Issue Unit / Instruction Line Buffer ...
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/SLB misses interrupt PPE „ „ „ Atomic Cache Facility ● „ „ 4 cache lines for atomic updates 2 cache lines for cast out/MMU reload ● Up to 16 outstanding DMA requests in BIU ● Resource / Bandwidth Management Tables Token Based Bus Access Management TLB Locking „ „ Legend: Data Bus Snoop Bus Control Bus X...
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Hypervisor) 4K Physical Page Boundary SPU Master Run Control SPU ID SPU ECC Control SPU ECC Status SPU ECC Address SPU 32 bit PU Interrupt Mailbox MFC Interrupt Mask MFC Interrupt Status MFC DMA Privileged Control MFC Command Error Register MFC Command Translation Fault Register MFC SDR (PT Anchor) MFC AC...
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) Michael Perrone © Copyrights by IBM Corp. and by other(s) 2007 66 6.189 IAP 2007 MIT Memory Flow Controller Commands DMA Commands Put - Transfer from Local Store to EA space Puts - Transfer and Start SPU execution Putr - Put Result - (Arch. Scarf into L2) Putl - Put using DMA List in Local Store Putrl - ...
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) 2007 67 6.189 IAP 2007 MIT SPE Structure ● Scalar processing supported on data-parallel substrate „ All instructions are data parallel and operate on vectors of elements „ Scalar operation defined by instruction use, not opcode – Vector instruction form used to perform operation ● Preferred slot paradigm „...
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Copyrights by IBM Corp. and by other(s) 2007 71 6.189 IAP 2007 MIT Element Interconnect Bus – Data Topology ● Four 16B data rings connecting 12 bus elements „ Two clockwise / Two counter-clockwise ● Physically overlaps all processor elements ● Central arbiter supports up to three concurrent transfers per data...
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3 SPE3 SPE5 SPE5 SPE7 SPE7 IOIF1 IOIF1 Ramp 6 Ramp Ramp 7 7 Ramp Ramp 8 8 Ramp Ramp 9 9 Ramp Ramp 10 10 Ramp Ramp 11 11 Controller Controller Controller Controller Controller Controller Controller Controller Controller Controller Controller Data Arbiter Controller Controller Controller Controll...
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20.110/5.60 Fall 2005 Lecture #5 page 1 Thermochemistry Much of thermochemistry is based on finding “easy” paths to calculate changes in enthalpy, i.e. understanding how to work with thermodynamic cycles. • Goal: To predict H∆ for every reaction, even if it cannot be carried out in the laboratory The heat of...
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• ∆ H f (° 298.15 K ) : The heat of formation is the heat of reaction to create 1 mole of that compound from its constituent elements in their most stable forms. Example (T = 298.15 K) ½ H2 (g,T,1 bar) + ½ Br2 (l,T,1 bar) = HBr (g,T,1 bar) ° ( H ∆ f HBr T , ) = ∆ H rx T bar ( ,1 ) = ° H HBr ( T g, ) − ( T g, ° H...
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: Linda G. Griffith, Kimberly Hamad-Schifferli, Moungi G. Bawendi, Robert W. Field 20.110/5.60 Fall 2005 Lecture #5 page 3 ∆HI CH4 (g,T,1 bar) = Cgraphite (s,T,1 bar) + 2H2(g,T,p) ∆HII 2O2 (g,T,1 bar) = 2O2 (g,T,1 bar) Cgraphite (s,T,1 bar) + ...
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2 ∴ In general, − ∆ H° 4f ,CH ∆ H rx = ∑ ν i i ∆ ° H f i , ( products ) − ∆ ° H f i , ( reactants ) ∑ ν i i ν ≡ stoichiometric coefficient • H∆ at constant p and for reversible pV process is = pH q ∆ ⇒ If If The heat of reaction is the heat flowing into the reaction from the surroundings ∆ H rx ∆ H rx < 0, p...
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II) ∆ IIH Prod. (T2) + Cal. (T2) = constant p Prod. (T1) + Cal. (T1) ________________________ ______ ________________________ ∆ rx TH React. (T) + Cal. (T) 1 1 1 ) ( = constant p Prod. (T) + Cal. (T) 1 1 ∆ ( TH rx 1 ) = ∆ H I + ∆ IH I 20.110J / 2.772J / 5.601JThermodynamics of Biomolecular SystemsInstructors: ...
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I ) ∆ IU React. (T1) + Cal. (T1) adiabatic = constant V Prod. (T2) + Cal. (T2) II) ∆ IIU Prod. (T 2) + Cal . (T ) 2 ________________________ = constant V ______ Prod T1 . ( ) + Cal. (T 1) ________________________ ∆ rx TU React. (T) + Cal. (T) = 1 1 1 ( ) constant V Prod. (T) + Cal. (T) 1 1 20.110J / 2.772J /...
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pV is from gases. Ideal gas Isothermal ∴ H T 1 rx ∆ ( ) = ⇒ ∆ ( ) pV = ⇒ ∆ T T ∆ R ( ) nT = ( ) = pV T R 1 1 ∆ n gas ∆ ) ( U T R 1 + rx ∆ T n 1 gas ∆ ( H T rx 1 ) = − T ∫ 2 VT 1 ( C od Cal dT R Pr . . + + ∆ T n 1 gas ) e.g. 4 HCl(g) + O2(g) = 2 H2O(l) + 2 Cl2(g) T1 = 298.15 K ∆ TU = -195.0 kJ rx ) 1 ( ∆ gasn ...
https://ocw.mit.edu/courses/20-110j-thermodynamics-of-biomolecular-systems-fall-2005/56de76a110080853b28006a5ce0b0620_l05.pdf
calculate ∆Hrx(T2) from the heat capacities of the reactants and products (assuming no phase change in any component). Reactants (T2) ∆HI constant p R eactants (T1) ∆ rxH T 2( → constant p ) Products (T2) ∆HII constant p ) Products (T1) ∆ rxH T 1( → constant p ( ( ( ) ) ) ∆ + ∆ H T H H T H + ∆ ∆ = rx 2 rx I I...
https://ocw.mit.edu/courses/20-110j-thermodynamics-of-biomolecular-systems-fall-2005/56de76a110080853b28006a5ce0b0620_l05.pdf