Results 1  10
of
7,400
Mit/lcs/tr 329
"... mechanisms whereby humans analyze complex systems abstractly, while ignoring unimportant and unknown lowlevel details. Previous research has focused on qualitative simulation techniques, analogous to numerical simulation, that use local information about a system to predict its shortterm behavior. ..."
Abstract
 Add to MetaCart
mechanisms whereby humans analyze complex systems abstractly, while ignoring unimportant and unknown lowlevel details. Previous research has focused on qualitative simulation techniques, analogous to numerical simulation, that use local information about a system to predict its shortterm behavior. This thesis presents a new, calculus based, type of qualitative analysis, called qualitative mathematical reasoning. It derives functional descriptions of systems and uses them to predict global behavior.
Mit/lcs/tr334
"... L'urrent efforts in ofce automation emphuise developinit toob for suppoFtinf common, lawlevel tasks such u word proceminf and electronic mail. nib. they have wide nmrket, they are not very sophisticated. At 'ihe other'end o( the .spectrum are oce*speciSc ' .sysuu, defipmd with c ..."
Abstract
 Add to MetaCart
L'urrent efforts in ofce automation emphuise developinit toob for suppoFtinf common, lawlevel tasks such u word proceminf and electronic mail. nib. they have wide nmrket, they are not very sophisticated. At 'ihe other'end o( the .spectrum are oce*speciSc ' .sysuu, defipmd with comidete knowledge dr the oflice's operatiou. Unfertutely, such systems hve nmrket sise o one, sad so are not very practical.
Mit/lcs/tr326
"... In a distributed system, an activity running at one node can request another node to perform some service. This request results in an activity being created at the latter node to perform the requested service. The former node may then crash, destroying the activity that requested the service, but ..."
Abstract
 Add to MetaCart
In a distributed system, an activity running at one node can request another node to perform some service. This request results in an activity being created at the latter node to perform the requested service. The former node may then crash, destroying the activity that requested the service, but leaving behind the activity performing the service. Such surviving activities are known as orphans [Nelson81]. Orphans are undesirable since they waste resources and can view inconsistent data.
Mit/lcs/tr357
"... A multiprogramming operating system needs a mechanism to recover from the termination of one of its computations. Cleaning up, or unlinkin(3 a terminated computation from those remaining requires identifying the end of a computation, freeing resources that the computation was uaing, and shutting dow ..."
Abstract
 Add to MetaCart
A multiprogramming operating system needs a mechanism to recover from the termination of one of its computations. Cleaning up, or unlinkin(3 a terminated computation from those remaining requires identifying the end of a computation, freeing resources that the computation was uaing, and shutting down its interfaces with other computations. This problem is especially important, and usually more difficult, when the computation fails.
T. BernersLee, MIT/LCS
, 1996
"... Status of this Memo This document is an InternetDraft. InternetDrafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as InternetDrafts. InternetDrafts are draft documents valid f ..."
Abstract
 Add to MetaCart
Status of this Memo This document is an InternetDraft. InternetDrafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as InternetDrafts. InternetDrafts are draft documents valid for a maximum of six months and may be updated, replaced, or made obsolete by other documents at any time. It is inappropriate to use InternetDrafts as reference material or to cite them other than as "work in progress". To learn the current status of any InternetDraft, please check the "1idabstracts.txt " listing contained in the InternetDrafts Shadow Directories on ftp.is.co.za (Africa), nic.nordu.net (Europe), munnari.oz.au (Pacific Rim), ds.internic.net (US East Coast), or ftp.isi.edu (US West Coast). Distribution of this document is unlimited. Please send comments to the
MIT/LCS/TM131 TIME, SPACE AND RANDOMNESS
, 1979
"... Space and time are the fundamental parameters of complexity theory. The thesis of this paper is that randomness is of equal importance. We introduce a notion of randomness (based on KolmogorovChaitinRandomness), which we suspect will contribute to the understanding of some of the central problem ..."
Abstract
 Add to MetaCart
Space and time are the fundamental parameters of complexity theory. The thesis of this paper is that randomness is of equal importance. We introduce a notion of randomness (based on KolmogorovChaitinRandomness), which we suspect will contribute to the understanding of some of the central problems in complexity theory. The purpose of this paper is primarily conceptual, though several easy theorems are given which clarify the relationship of this notion of randomness to the NP = P question, the complexity of integer factoring, and the sets computable in random polynomial time. Finally, using factoring as an example, we raise the possibility of performing experiments on functions of unknown complexity to indicate the extent of their tractability. 3 I. Motivation An analogy with chemistry At a philosophical level there is a similarity between chemistry and num
MITLCSTM653 Subcontracted Rational SFE
, 2005
"... In their paper, “Rational Secure Computation and Ideal Mechanism Design, ” Izmalkov, Lepinski and Micali show that any oneshot mediated game can be simulated by the players themselves, without the help of a trusted mediator, using physical envelopes and a ballotbox. We show that communication be ..."
Abstract
 Add to MetaCart
In their paper, “Rational Secure Computation and Ideal Mechanism Design, ” Izmalkov, Lepinski and Micali show that any oneshot mediated game can be simulated by the players themselves, without the help of a trusted mediator, using physical envelopes and a ballotbox. We show that communication between the players is not essential to the ILM protocol. That is, we provide a protocol for rational secure function evaluation (Rational SFE) where the players just send a set of envelopes to a referee who simply performs a sequence of publicly verifiable actions. That is, the players can “subcontract ” all of the computation to an untrusted referee. In addition to providing a communication structure that more closely matches the ideal game, our protocol also enables us to better simulate mediated games in which abort is not a dominated action. 1 Prior Work The general notion of secure multiparty computation was put forward and exemplified by Goldreich, Micali and Wigderson [3], based on the twoparty results of Yao [6]. In particular,
MITLCSTR1010 On Field Constraint Analysis
, 2005
"... Abstract. We introduce field constraint analysis, a new technique for verifying data structure invariants. A field constraint for a field is a formula specifying a set of objects to which the field can point. Field constraints enable the application of decidable logics to data structures which wer ..."
Abstract
 Add to MetaCart
Abstract. We introduce field constraint analysis, a new technique for verifying data structure invariants. A field constraint for a field is a formula specifying a set of objects to which the field can point. Field constraints enable the application of decidable logics to data structures which were originally beyond the scope of these logics, by verifying the backbone of the data structure and then verifying constraints on fields that crosscut the backbone in arbitrary ways. Previously, such crosscutting fields could only be verified when they were uniquely determined by the backbone, which significantly limited the range of analyzable data structures. Our field constraint analysis permits nondeterministic field constraints on crosscutting fields, which allows to verify invariants of data structures such as skip lists. Nondeterministic field constraints also enable the verification of invariants between data structures, yielding an expressive generalization of static type declarations. The generality of our field constraints requires new techniques, which are orthogonal to the traditional use of structure simulation. We present one such technique and prove its soundness. We have implemented this technique as part of a symbolic shape analysis deployed in the context of the Hob system for verifying data structure consistency. Using this implementation we were able to verify data structures that were previously beyond the reach of similar techniques.
The Fastest Fourier Transform in the West. MITLCSTR728
 the Proceedings of the 1998 International Conference on Acoustics, Speech, and Signal Processing, ICASSP '98
, 1997
"... This paper describes FFTW, a portable C package for computing the one and multidimensional complex discrete Fourier transform (DFT). FFTW is typically faster than all other publicly available DFT software, including the wellknown FFTPACK and the code from Numerical Recipes. More interestingly, FFT ..."
Abstract

Cited by 2 (0 self)
 Add to MetaCart
This paper describes FFTW, a portable C package for computing the one and multidimensional complex discrete Fourier transform (DFT). FFTW is typically faster than all other publicly available DFT software, including the wellknown FFTPACK and the code from Numerical Recipes. More interestingly, FFTW is competitive with or better than proprietary, highlytuned codes such as Sun’s Performance Library and IBM’s ESSL library. FFTW implements the CooleyTukey fast Fourier transform, and is freely available on the Web at
MITLCSTR990 Theoretical Analysis of Geographic Routing in Social Networks
, 2005
"... We introduce a formal model for geographic social networks, and introduce the notion of rankbased friendship, in which the probability that a person v is a friend of a person u is inversely proportional to the number of people w who live closer to u than v does. We then prove our main theorem, show ..."
Abstract
 Add to MetaCart
We introduce a formal model for geographic social networks, and introduce the notion of rankbased friendship, in which the probability that a person v is a friend of a person u is inversely proportional to the number of people w who live closer to u than v does. We then prove our main theorem, showing that rankbased friendship is a sufficient explanation of the navigability of any geographic social network that adheres to it. 1 A Model of Population Networks There are two key features that we wish to incorporate into our socialnetwork model: geography and population density. We will first describe a very general abstract model; in later sections we examine a concrete gridbased instantiation of it. Definition 1.1 (Population network) A population network is a 5tuple 〈L, d, P, loc, E 〉 where • L is a finite set of locations (, s, t, x, y, z,...); • d: L × L − → R+ is an arbitrary distance function on the locations; • P is a finite ordered set of people (u, v, w,...); • loc: P − → L is the location function, which maps people to the location in which they live;
Results 1  10
of
7,400