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Computational Learning Theory: New Models and Algorithms
Computational Learning Theory: New Models and Algorithms by Robert Hal Sloan S.M. EECS, Massachusetts Institute of Technology (1986) B.S. Mathematics, Yale University (1983) Submitted to the Department- of Electrical Engineering and Computer Science in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the MASSACHUSETTS INSTITUTE OF TECHNOLOGY June 1989 @ Robert Hal Sloan, 1989. All rights reserved The author hereby grants to MIT permission to reproduce and to distribute copies of this thesis document in whole or in part. Signature of Author Department of Electrical Engineering and Computer Science May 23, 1989 Certified by Ronald L. Rivest Professor of Computer Science Thesis Supervisor Accepted by Arthur C. Smith Chairman, Departmental Committee on Graduate Students Abstract In the past several years, there has been a surge of interest in computational learning theory-the formal (as opposed to empirical) study of learning algorithms. One major cause for this interest was the model of probably approximately correct learning, or pac learning, introduced by Valiant in 1984. This thesis begins by presenting a new learning algorithm for a particular problem within that model: learning submodules of the free Z-module Zk. We prove that this algorithm achieves probable approximate correctness, and indeed, that it is within a log log factor of optimal in a related, but more stringent model of learning, on-line mistake bounded learning. We then proceed to examine the influence of noisy data on pac learning algorithms in general. Previously it has been shown that it is possible to tolerate large amounts of random classification noise, but only a very small amount of a very malicious sort of noise. -
Security Analysis of Cryptographically Controlled Access to XML Documents
Security Analysis of Cryptographically Controlled Access to XML Documents ¤ Mart´in Abadi Bogdan Warinschi Computer Science Department Computer Science Department University of California at Santa Cruz Stanford University [email protected] [email protected] ABSTRACT ments [4, 5, 7, 8, 14, 19, 23]. This line of research has led to Some promising recent schemes for XML access control em- e±cient and elegant publication techniques that avoid data ploy encryption for implementing security policies on pub- duplication by relying on cryptography. For instance, us- lished data, avoiding data duplication. In this paper we ing those techniques, medical records may be published as study one such scheme, due to Miklau and Suciu. That XML documents, with parts encrypted in such a way that scheme was introduced with some intuitive explanations and only the appropriate users (physicians, nurses, researchers, goals, but without precise de¯nitions and guarantees for the administrators, and patients) can see their contents. use of cryptography (speci¯cally, symmetric encryption and The work of Miklau and Suciu [19] is a crisp, compelling secret sharing). We bridge this gap in the present work. We example of this line of research. They develop a policy query analyze the scheme in the context of the rigorous models language for specifying ¯ne-grained access policies on XML of modern cryptography. We obtain formal results in sim- documents and a logical model based on the concept of \pro- ple, symbolic terms close to the vocabulary of Miklau and tection". They also show how to translate consistent poli- Suciu. We also obtain more detailed computational results cies into protections, and how to implement protections by that establish security against probabilistic polynomial-time XML encryption [10]. -
ITERATIVE ALGOR ITHMS for GLOBAL FLOW ANALYSIS By
ITERATIVE ALGOR ITHMS FOR GLOBAL FLOW ANALYSIS bY Robert Endre Tarjan STAN-CS-76-547 MARCH 1976 COMPUTER SCIENCE DEPARTMENT School of Humanities and Sciences STANFORD UN IVERS ITY Iterative Algorithms for Global Flow Analysis * Robert Endre Tarjan f Computer Science Department Stanford University Stanford, California 94305 February 1976 Abstract. This paper studies iterative methods for the global flow analysis of computer programs. We define a hierarchy of global flow problem classes, each solvable by an appropriate generalization of the "node listing" method of Kennedy. We show that each of these generalized methods is optimum, among all iterative algorithms, for solving problems within its class. We give lower bounds on the time required by iterative algorithms for each of the problem classes. Keywords: computational complexity, flow graph reducibility, global flow analysis, graph theory, iterative algorithm, lower time bound, node listing. * f Research partially supported by National Science Foundation grant MM 75-22870. 1 t 1. Introduction. A problem extensively studied in recent years [2,3,5,7,8,9,12,13,14, 15,2'7,28,29,30] is that of globally analyzing cmputer programs; that is, collecting information which is distributed throughout a computer program, generally for the purpose of optimizing the program. Roughly speaking, * global flow analysis requires the determination, for each program block f , of a property known to hold on entry to the block, independent of the path taken to reach the block. * A widely used amroach to global flow analysis is to model the set of possible properties by a semi-lattice (we desire the 'lmaximumtl property for each block), to model the control structure of the program by a directed graph with one vertex for each program block, and to specify, for each branch from block to block, the function by which that branch transforms the set of properties. -
Interview with James Mitchell
Interview with James Mitchell Interviewed by: David C. Brock Recorded February 19, 2019 Santa Barbara, CA CHM Reference number: X8963.2019 © 2019 Computer History Museum Interview with James Mitchell Brock: Yeah. So, yeah, maybe we can talk about your transition from Carnegie Mellon to PARC and how that opportunity came about, and what your thinking was about joining the new lab. Mitchell: I basically finished my PhD and left in July of 1970. I had missed graduation that year, so my diploma says 1971. But, in fact, I'd been out working for a year by then, and at PARC, you know, there were a number of other grad students I knew, and two of them had gone to work for a start-up in Berkeley that-- there were two Berkeley computer science departments, and the engineering one left to form this company called Berkeley Computer Corporation with Mel Pirtle running it and Butler Lampson kind of a chief technical officer and Chuck Thacker and so on, and anyway the people that I-- the two other grad students that had gone already that I knew, when I was going out, I was starting to go around and interview in early 1970 because I knew I was close to being finished, and it was in those days because there were so few people who had PhDs in computer science and every university was trying to build a department, and industrial research places like Bell Labs were trying to hire people and so on, anywhere you went with a new PhD you got an offer. -
The People Who Invented the Internet Source: Wikipedia's History of the Internet
The People Who Invented the Internet Source: Wikipedia's History of the Internet PDF generated using the open source mwlib toolkit. See http://code.pediapress.com/ for more information. PDF generated at: Sat, 22 Sep 2012 02:49:54 UTC Contents Articles History of the Internet 1 Barry Appelman 26 Paul Baran 28 Vint Cerf 33 Danny Cohen (engineer) 41 David D. Clark 44 Steve Crocker 45 Donald Davies 47 Douglas Engelbart 49 Charles M. Herzfeld 56 Internet Engineering Task Force 58 Bob Kahn 61 Peter T. Kirstein 65 Leonard Kleinrock 66 John Klensin 70 J. C. R. Licklider 71 Jon Postel 77 Louis Pouzin 80 Lawrence Roberts (scientist) 81 John Romkey 84 Ivan Sutherland 85 Robert Taylor (computer scientist) 89 Ray Tomlinson 92 Oleg Vishnepolsky 94 Phil Zimmermann 96 References Article Sources and Contributors 99 Image Sources, Licenses and Contributors 102 Article Licenses License 103 History of the Internet 1 History of the Internet The history of the Internet began with the development of electronic computers in the 1950s. This began with point-to-point communication between mainframe computers and terminals, expanded to point-to-point connections between computers and then early research into packet switching. Packet switched networks such as ARPANET, Mark I at NPL in the UK, CYCLADES, Merit Network, Tymnet, and Telenet, were developed in the late 1960s and early 1970s using a variety of protocols. The ARPANET in particular led to the development of protocols for internetworking, where multiple separate networks could be joined together into a network of networks. In 1982 the Internet Protocol Suite (TCP/IP) was standardized and the concept of a world-wide network of fully interconnected TCP/IP networks called the Internet was introduced. -
Second International Computer Programming Education Conference
Second International Computer Programming Education Conference ICPEC 2021, May 27–28, 2021, University of Minho, Braga, Portugal Edited by Pedro Rangel Henriques Filipe Portela Ricardo Queirós Alberto Simões OA S I c s – Vo l . 91 – ICPEC 2021 www.dagstuhl.de/oasics Editors Pedro Rangel Henriques Universidade do Minho, Portugal [email protected] Filipe Portela Universidade do Minho, Portugal [email protected] Ricardo Queirós Politécnico do Porto, Portugal [email protected] Alberto Simões Politécnico do Cávado e Ave, Portugal [email protected] ACM Classifcation 2012 Applied computing → Education ISBN 978-3-95977-194-8 Published online and open access by Schloss Dagstuhl – Leibniz-Zentrum für Informatik GmbH, Dagstuhl Publishing, Saarbrücken/Wadern, Germany. Online available at https://www.dagstuhl.de/dagpub/978-3-95977-194-8. Publication date July, 2021 Bibliographic information published by the Deutsche Nationalbibliothek The Deutsche Nationalbibliothek lists this publication in the Deutsche Nationalbibliografe; detailed bibliographic data are available in the Internet at https://portal.dnb.de. License This work is licensed under a Creative Commons Attribution 4.0 International license (CC-BY 4.0): https://creativecommons.org/licenses/by/4.0/legalcode. In brief, this license authorizes each and everybody to share (to copy, distribute and transmit) the work under the following conditions, without impairing or restricting the authors’ moral rights: Attribution: The work must be attributed to its authors. The copyright is retained by the corresponding authors. Digital Object Identifer: 10.4230/OASIcs.ICPEC.2021.0 ISBN 978-3-95977-194-8 ISSN 1868-8969 https://www.dagstuhl.de/oasics 0:iii OASIcs – OpenAccess Series in Informatics OASIcs is a series of high-quality conference proceedings across all felds in informatics. -
A Auxiliary Definitions
A Auxiliary Definitions This appendix contains auxiliary definitions omitted from the main text. Variables fun lvars :: com ⇒ vname set where lvars SKIP = {} lvars (x ::= e)={x} lvars (c1;; c2)=lvars c1 ∪ lvars c2 lvars (IF b THEN c1 ELSE c2)=lvars c1 ∪ lvars c2 lvars (WHILE b DO c)=lvars c fun rvars :: com ⇒ vname set where rvars SKIP = {} rvars (x ::= e)=vars e rvars (c1;; c2)=rvars c1 ∪ rvars c2 rvars (IF b THEN c1 ELSE c2)=vars b ∪ rvars c1 ∪ rvars c2 rvars (WHILE b DO c)=vars b ∪ rvars c definition vars :: com ⇒ vname set where vars c = lvars c ∪ rvars c Abstract Interpretation fun strip :: aacom⇒ com where strip (SKIP {P})=SKIP strip (x ::= e {P})=x ::= e © Springer International Publishing Switzerland 2014 281 T. Nipkow and G. Klein, Concrete Semantics, DOI 10.1007/978-3-319-10542-0 282 A Auxiliary Definitions strip (C 1;;C 2)=strip C 1;; strip C 2 strip (IF b THEN {P 1} C 1 ELSE {P 2} C 2 {P})= IF b THEN strip C 1 ELSE strip C 2 strip ({I } WHILE b DO {P} C {Q})=WHILE b DO strip C fun annos :: aacom⇒ a list where annos (SKIP {P})=[P] annos (x ::= e {P})=[P] annos (C 1;;C 2)=annos C 1 @ annos C 2 annos (IF b THEN {P 1} C 1 ELSE {P 2} C 2 {Q})= P 1 # annos C 1 @ P 2 # annos C 2 @ [Q] annos ({I } WHILE b DO {P} C {Q})=I # P # annos C @ [Q] fun asize :: com ⇒ nat where asize SKIP = 1 asize (x ::= e)=1 asize (C 1;;C 2)=asize C 1 + asize C 2 asize (IF b THEN C 1 ELSE C 2)=asize C 1 + asize C 2 + 3 asize (WHILE b DO C )=asize C + 3 definition shift :: (nat ⇒ a) ⇒ nat ⇒ nat ⇒ a where shift f n =(λp. -
The Optical Mouse: Early Biomimetic Embedded Vision
The Optical Mouse: Early Biomimetic Embedded Vision Richard F. Lyon Abstract The 1980 Xerox optical mouse invention, and subsequent product, was a successful deployment of embedded vision, as well as of the Mead–Conway VLSI design methodology that we developed at Xerox PARC in the late 1970s. The de- sign incorporated an interpretation of visual lateral inhibition, essentially mimicking biology to achieve a wide dynamic range, or light-level-independent operation. Con- ceived in the context of a research group developing VLSI design methodologies, the optical mouse chip represented an approach to self-timed semi-digital design, with the analog image-sensing nodes connecting directly to otherwise digital logic using a switch-network methodology. Using only a few hundred gates and pass tran- sistors in 5-micron nMOS technology, the optical mouse chip tracked the motion of light dots in its field of view, and reported motion with a pair of 2-bit Gray codes for x and y relative position—just like the mechanical mice of the time. Besides the chip, the only other electronic components in the mouse were the LED illuminators. Fig. 1 The Xerox optical mouse chip in its injection- molded dual-inline package (DIP) of clear plastic, with pins stuck into a conductive packaging foam. The bond wires connecting the chip’s pads to the lead frame are (barely) visible. Richard F. Lyon Google Inc., Mountain View CA, e-mail: [email protected] 1 2 Richard F. Lyon Fig. 2 The Winter 1982 Xe- rox World internal magazine cover featuring the Electron- ics Division and their 3-button mechanical and optical mouse developments, among other electronic developments. -
Technology and Courage
Technology and Courage Ivan Sutherland Perspectives 96-1 In an Essay Series Published by SunLabs April 1996 _____________________________________________________________________________ © Copyright 1996 Sun Microsystems, Inc. Perspectives, a new and parallel series to the Sun Microsystems Laboratories Technical Report Series, is published by Sun Microsystems Laboratories, a division of Sun Microsystems, Inc. Printed in U.S.A. Unlimited copying without fee is permitted provided that the copies are not made nor distributed for direct commercial advantage, and credit to the source is given. Otherwise, no part of this work covered by copyright hereon may be reproduced in any form or by any means graphic, electronic, or mechanical, including photocopying, recording, taping, or storage in an information retrieval system, without the prior written permission of the copyright owner. TRADEMARKS Sun, Sun Microsystems, and the Sun logo are trademarks or registered trademarks of Sun Microsystems, Inc. UNIX is a registered trademark in the United States and other countries, exclusively licensed through X/Open Company, Ltd. All SPARC trademarks, including the SCD Compliant Logo, are trademarks or registered trademarks of SPARC International, Inc. SPARCstation, SPARCserver, SPARCengine, SPARCworks, and SPARCompiler are licensed exclusively to Sun Microsystems, Inc. All other product names mentioned herein are the trademarks of their respec- tive owners. For information regarding the SunLabs Perspectives Series, contact Jeanie Treichel, Editor-in-Chief <[email protected]>. For distribution issues, contact Amy Tashbook Hall, Assistant Editor <[email protected]>. _____________________________________________________________________________ Editor’s Notes About the series— The Perspectives series is a collection of essays written by individuals from Sun Microsystems Laboratories. These essays express ideas and opinions held by the authors on subjects of general rather than technical interest. -
Statement on the Selection of Jeffrey Ullman for a Turing Award
Statement on the Selection of Jeffrey Ullman for a Turing Award An Open Letter to Committee of the ACM A.M. Turing Award and ACM: Date: 04/16/2021 Professor Jeffrey D. Ullman of Stanford University has been chosen to receive the 2020 ACM A.M. Turing Award, generally regarded as the highest distinction in computing. While we agree that the technical and educational contributions of Professor Ullman could meet the bar for a “Nobel Prize of Computing”, we condemn the selection as one that directly goes against the Diversity and Inclusion (D & I) values that the Computer Science community, and the Association for Computing Machinery (ACM) in particular, aim to uphold. While we recognize Professor Ullman’s freedom of speech and freedom to hold and express his political views, we are concerned by his sustained discriminatory behavior against students and by ACM bestowing upon such a person an award named after Alan Turing, someone who suffered much discrimination in his tragic life [1]. ACM defines its mission as follows: “ACM is a global scientific and educational organization dedicated to advancing the art, science, engineering, and application of computing, serving both professional and public interests by fostering the open exchange of information and by promoting the highest professional and ethical standards.” Furthermore, ACM explicitly defines “Diversity and Inclusion” as one of its four core values [2]. We assert, based on documented evidence, that not only has Professor Ullman willfully violated the “highest professional and ethical standards” that ACM has the mission to uphold, but also that he has demonstrated a pattern of actively turning against the values of D & I for decades. -
Conway-Suchman Conversation
Conway Suchman Conversation Conway-Suchman conversation Lynn Conway, Lucy Suchman Published on: Mar 05, 2021 License: Creative Commons Attribution 4.0 International License (CC-BY 4.0) Conway Suchman Conversation Conway-Suchman conversation Preface by Lucy Suchman, 28 February 2021 In 1980, at Xerox’s Palo Alto Research Center (PARC), we entered into a rather extraordinary conversation. Computer architect and electrical engineer Lynn was then head of the LSI (Large-Scale Integration) Systems area at PARC, while I was a recently arrived Research Intern at PARC and PhD student in Anthropology at the University of California at Berkeley, in the very early stages of formulating plans for my doctoral thesis. Lynn was emerging from a period of intensive activity focused on the ‘multi-university, multi-project chip-design demonstration’ (MPC79), an initiative involving the creation of a new pedagogy and associated design and manufacturing process for the production of very large-scale integrated circuits (VLSI). At Lynn’s suggestion, we began an exchange born out of her desire to think anthropologically about what she had just experienced, and mine to deepen my understanding of her sociotechnical imaginary and practice. With Lynn’s endorsement, I recorded and transcribed our conversations, aided by an Alto computer and the text editor Bravo, both recently developed and in everyday use at PARC. The resulting text, which I printed out to share with Lynn and archived for herself in a 3-ring binder, was around 55 pages. We lost touch over the years following our respective departures from PARC until, in 2020, another PhD student, Philipp Sander, contacted Lynn to interview her. -
Assembling a Prehistory for Formal Methods: a Personal View Thomas Haigh [email protected]
Assembling A Prehistory for Formal Methods: A Personal View Thomas Haigh [email protected] University of Wisconsin—Milwaukee & Siegen University www.tomandmaria.com This is a preprint copy. Please quote and cite the final version, which will appear in a special issue of Formal Aspects of Computing devoted to historical work. Thanks to Cliff Jones and the anonymous reviewers for their encouragement and feedback on earlier drafts of this paper. Preprint Draft Haigh – Assembling a History for Formal Methods 2 Although I was pleased to be asked to contribute something to this volume I have a confession to make: I have never studied the history of formal methods. So this is not going to be a history of formal methods as much as a reflection on how such a story might be written. My plan is to triangulate from my personal experiences as a computer science student a quarter century ago, my Ph.D. training as a historian of science and technology, and my subsequent career researching and writing about various aspects of the history of computing. The fact that, despite a general familiarity with the literature on the history of computing, I don’t have a better grasp of the history of formal methods tells us a lot about the need for this special issue. Most of the history is so far locked up in the heads of participants, which is not a convenient place for the rest of us to find it. Stories written by participants or people with a personal connection to the events described are not usually the last word on historical events, but they are a vital starting point.