Distributed Network Algorithms (Lecture Notes for GIAN Course)
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Efficient Algorithms with Asymmetric Read and Write Costs
Efficient Algorithms with Asymmetric Read and Write Costs Guy E. Blelloch1, Jeremy T. Fineman2, Phillip B. Gibbons1, Yan Gu1, and Julian Shun3 1 Carnegie Mellon University 2 Georgetown University 3 University of California, Berkeley Abstract In several emerging technologies for computer memory (main memory), the cost of reading is significantly cheaper than the cost of writing. Such asymmetry in memory costs poses a fun- damentally different model from the RAM for algorithm design. In this paper we study lower and upper bounds for various problems under such asymmetric read and write costs. We con- sider both the case in which all but O(1) memory has asymmetric cost, and the case of a small cache of symmetric memory. We model both cases using the (M, ω)-ARAM, in which there is a small (symmetric) memory of size M and a large unbounded (asymmetric) memory, both random access, and where reading from the large memory has unit cost, but writing has cost ω 1. For FFT and sorting networks we show a lower bound cost of Ω(ωn logωM n), which indicates that it is not possible to achieve asymptotic improvements with cheaper reads when ω is bounded by a polynomial in M. Moreover, there is an asymptotic gap (of min(ω, log n)/ log(ωM)) between the cost of sorting networks and comparison sorting in the model. This contrasts with the RAM, and most other models, in which the asymptotic costs are the same. We also show a lower bound for computations on an n × n diamond DAG of Ω(ωn2/M) cost, which indicates no asymptotic improvement is achievable with fast reads. -
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. -
Guide to the Systems Engineering Body of Knowledge (Sebok) Version 1.3
Guide to the Systems Engineering Body of Knowledge (SEBoK) version 1.3 Released May 30, 2014 Part 2: Systems Please note that this is a PDF extraction of the content from www.sebokwiki.org Copyright and Licensing A compilation copyright to the SEBoK is held by The Trustees of the Stevens Institute of Technology ©2014 (“Stevens”) and copyright to most of the content within the SEBoK is also held by Stevens. Prominently noted throughout the SEBoK are other items of content for which the copyright is held by a third party. These items consist mainly of tables and figures. In each case of third party content, such content is used by Stevens with permission and its use by third parties is limited. Stevens is publishing those portions of the SEBoK to which it holds copyright under a Creative Commons Attribution-NonCommercial ShareAlike 3.0 Unported License. See http://creativecommons.org/licenses/by-nc-sa/3.0/deed.en_US for details about what this license allows. This license does not permit use of third party material but gives rights to the systems engineering community to freely use the remainder of the SEBoK within the terms of the license. Stevens is publishing the SEBoK as a compilation including the third party material under the terms of a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported (CC BY-NC-ND 3.0). See http://creativecommons.org/licenses/by-nc-nd/3.0/ for details about what this license allows. This license will permit very limited noncommercial use of the third party content included within the SEBoK and only as part of the SEBoK compilation. -
System Archetypes As a Learning Aid Within a Tourism Business Planning Software Tool
System Archetypes as a Learning Aid Within a Tourism Business Planning Software Tool G. Michael McGrath Centre for Hospitality and Tourism Research, Victoria University, Melbourne Email: [email protected] ABSTRACT Various studies have identified a need for improved business planning among Small-to-Medium Tourism Enterprise (SMTE) operators. The tourism sector is characterized by complexity, rapid change and interactions between many competing and cooperating sub-systems. System dynamics (SD) has proven itself to be an excellent discipline for capturing and modelling precisely this type of domain. In this paper, we report on an SD-based Tourism Enterprise Planning Simulator (TEPS) and its use as a learning aid within a business planning context. Particular emphasis is focussed on system archetypes. Keywords: tourism, business planning software, system dynamics. 1. Introduction In a recent study conducted for the Australian Sustainable Tourism Cooperative Research Centre (STCRC), improved business planning was identified as one of the most pressing needs of Small-to- Medium Tourism Enterprise (SMTE) operators (McGrath, 2005). A further significant problem confronting these businesses was coping with rapid change: including technological change, major changes in the external business environment, and changes that are having substantial impacts at every point of the tourism supply chain (and at every level – from international to regional and local levels). As a result of these findings, the STCRC provided funding and support for a follow-up research project aimed at producing a Tourism Enterprise Planning Simulator (TEPS). Distinguishing features of TEPS are: • Extensive use is made of system dynamics (SD) modelling technologies and tools (for capturing and simulating key aspects of change). -
Thinking by Ian Bradbury
Downloaded from the Curious Cat Management Improvement Library: http://www.curiouscat.net/library/ So, what's System[s] Thinking by Ian Bradbury System[s] thinking is an area that has attracted quite a lot of attention in recent years. This brief article seeks to introduce the first of two key ideas in system[s] thinking, relate it to popular writings on the subject and illustrate the concept. (the second part, originally published as a second article, is included below) Interdependence Ludwig von Bertalanffy said that in dealing with complexes of elements, three different kinds of distinction may be made: 1) According to their number, 2) According to their species and 3) According to the relations of elements. 1. vs. 2. vs. 3. vs. In cases 1 and 2, the complex may be understood as the sum of elements considered in isolation. In case 3, not only the elements, but also the relationships between them need to be known for the complex to be understood. Characteristics of the first kind are called summative, of the second kind constitutive. Complexes that are constitutive in nature are what is meant by the old phrase "The whole is more than the sum of the parts." An example of cases 1 and 2 might be the value of the change in your pocket. The value of the change taken altogether is obtained by simply summing up the values of the individual coins taken separately. An example of case 3, used frequently by Russell Ackoff to illustrate a constitutive complex, is a car [or truck if preferred]. -
Four Results of Jon Kleinberg a Talk for St.Petersburg Mathematical Society
Four Results of Jon Kleinberg A Talk for St.Petersburg Mathematical Society Yury Lifshits Steklov Institute of Mathematics at St.Petersburg May 2007 1 / 43 2 Hubs and Authorities 3 Nearest Neighbors: Faster Than Brute Force 4 Navigation in a Small World 5 Bursty Structure in Streams Outline 1 Nevanlinna Prize for Jon Kleinberg History of Nevanlinna Prize Who is Jon Kleinberg 2 / 43 3 Nearest Neighbors: Faster Than Brute Force 4 Navigation in a Small World 5 Bursty Structure in Streams Outline 1 Nevanlinna Prize for Jon Kleinberg History of Nevanlinna Prize Who is Jon Kleinberg 2 Hubs and Authorities 2 / 43 4 Navigation in a Small World 5 Bursty Structure in Streams Outline 1 Nevanlinna Prize for Jon Kleinberg History of Nevanlinna Prize Who is Jon Kleinberg 2 Hubs and Authorities 3 Nearest Neighbors: Faster Than Brute Force 2 / 43 5 Bursty Structure in Streams Outline 1 Nevanlinna Prize for Jon Kleinberg History of Nevanlinna Prize Who is Jon Kleinberg 2 Hubs and Authorities 3 Nearest Neighbors: Faster Than Brute Force 4 Navigation in a Small World 2 / 43 Outline 1 Nevanlinna Prize for Jon Kleinberg History of Nevanlinna Prize Who is Jon Kleinberg 2 Hubs and Authorities 3 Nearest Neighbors: Faster Than Brute Force 4 Navigation in a Small World 5 Bursty Structure in Streams 2 / 43 Part I History of Nevanlinna Prize Career of Jon Kleinberg 3 / 43 Nevanlinna Prize The Rolf Nevanlinna Prize is awarded once every 4 years at the International Congress of Mathematicians, for outstanding contributions in Mathematical Aspects of Information Sciences including: 1 All mathematical aspects of computer science, including complexity theory, logic of programming languages, analysis of algorithms, cryptography, computer vision, pattern recognition, information processing and modelling of intelligence. -
Navigability of Small World Networks
Navigability of Small World Networks Pierre Fraigniaud CNRS and University Paris Sud http://www.lri.fr/~pierre Introduction Interaction Networks • Communication networks – Internet – Ad hoc and sensor networks • Societal networks – The Web – P2P networks (the unstructured ones) • Social network – Acquaintance – Mail exchanges • Biology (Interactome network), linguistics, etc. Dec. 19, 2006 HiPC'06 3 Common statistical properties • Low density • “Small world” properties: – Average distance between two nodes is small, typically O(log n) – The probability p that two distinct neighbors u1 and u2 of a same node v are neighbors is large. p = clustering coefficient • “Scale free” properties: – Heavy tailed probability distributions (e.g., of the degrees) Dec. 19, 2006 HiPC'06 4 Gaussian vs. Heavy tail Example : human sizes Example : salaries µ Dec. 19, 2006 HiPC'06 5 Power law loglog ppk prob{prob{ X=kX=k }} ≈≈ kk-α loglog kk Dec. 19, 2006 HiPC'06 6 Random graphs vs. Interaction networks • Random graphs: prob{e exists} ≈ log(n)/n – low clustering coefficient – Gaussian distribution of the degrees • Interaction networks – High clustering coefficient – Heavy tailed distribution of the degrees Dec. 19, 2006 HiPC'06 7 New problematic • Why these networks share these properties? • What model for – Performance analysis of these networks – Algorithm design for these networks • Impact of the measures? • This lecture addresses navigability Dec. 19, 2006 HiPC'06 8 Navigability Milgram Experiment • Source person s (e.g., in Wichita) • Target person t (e.g., in Cambridge) – Name, professional occupation, city of living, etc. • Letter transmitted via a chain of individuals related on a personal basis • Result: “six degrees of separation” Dec. -
Success in Acquisition: Using Archetypes to Beat the Odds
Success in Acquisition: Using Archetypes to Beat the Odds William E. Novak Linda Levine September 2010 TECHNICAL REPORT CMU/SEI-2010-TR-016 ESC-TR-2010-016 Acquisition Support Program Unlimited distribution subject to the copyright. http://www.sei.cmu.edu This report was prepared for the SEI Administrative Agent ESC/XPK 5 Eglin Street Hanscom AFB, MA 01731-2100 The ideas and findings in this report should not be construed as an official DoD position. It is published in the interest of scientific and technical information exchange. This work is sponsored by the U.S. Department of Defense. The Software Engineering Institute is a federally funded research and development center sponsored by the U.S. Department of Defense. Copyright 2010 Carnegie Mellon University. NO WARRANTY THIS CARNEGIE MELLON UNIVERSITY AND SOFTWARE ENGINEERING INSTITUTE MATERIAL IS FURNISHED ON AN “AS-IS” BASIS. CARNEGIE MELLON UNIVERSITY MAKES NO WARRANTIES OF ANY KIND, EITHER EXPRESSED OR IMPLIED, AS TO ANY MATTER INCLUDING, BUT NOT LIMITED TO, WARRANTY OF FITNESS FOR PURPOSE OR MERCHANTABILITY, EXCLUSIVITY, OR RESULTS OBTAINED FROM USE OF THE MATERIAL. CARNEGIE MELLON UNIVERSITY DOES NOT MAKE ANY WARRANTY OF ANY KIND WITH RESPECT TO FREEDOM FROM PATENT, TRADEMARK, OR COPYRIGHT INFRINGEMENT. Use of any trademarks in this report is not intended in any way to infringe on the rights of the trademark holder. Internal use. Permission to reproduce this document and to prepare derivative works from this document for inter- nal use is granted, provided the copyright and “No Warranty” statements are included with all reproductions and derivative works. External use. -
Embedding Learning Aids in System Archetypes
Embedding Learning Aids in System Archetypes Veerendra K Rai * and Dong-Hwan Kim+ * Systems Research Laboratory, Tata Consultancy Services 54B, Hadapsar Industrial Estate, Pune- 411 013, India, [email protected] + Chung –Ang University, School of Public Affairs, Kyunggi-Do, Ansung-Si, Naeri, 456-756, South Korea, [email protected] Abstract: This paper revisits the systems archetypes proposed in The Fifth Discipline. Authors believe there exists a framework, which explains how these archetypes arise. Besides, the framework helps integrate the archetypes and infer principles of organizational learning. It takes the system archetypes as problem archetypes and endeavors to suggest solution by embedding simple learning aids in the archetypes. Authors believe problem in the systems do not arise due to the failure of a single paramount decision-maker. More often than not the problems are manifestations of cumulative and compound failures of all players in the system. Since system dynamics does not account for the behavior of individual actors in the system and it accounts for the individual behavior only by aggregation the only way it can hope to improve the behavior of individual actors is by taking system thinking to their doorsteps. Key words: System archetypes, organizational learning, learning principles, 1. Introduction The old model, “the top thinks and local acts” must now give way to integrating thinking and acting at all levels, thus remarked Peter Senge in the article ‘Leader’s New Work’ (Senge, 1990). Entire universe participates in any given event and thus entire universe is the cause of the event (Maharaj, 1973). However, we must place a boundary to carve out our system in focus in order to understand and solve a ‘problem’ whatever it means. -
A Systems Engineering Framework for Bioeconomic Transitions in a Sustainable Development Goal Context
sustainability Article A Systems Engineering Framework for Bioeconomic Transitions in a Sustainable Development Goal Context Erika Palmer 1,* , Robert Burton 1 and Cecilia Haskins 2 1 Ruralis—Institute for Rural and Regional Research, N-7049 Trondheim, Norway; [email protected] 2 Department of Mechanical and Industrial Engineering, Norwegian University of Science and Technology, 7491 Trondheim, Norway; [email protected] * Correspondence: [email protected] Received: 3 July 2020; Accepted: 13 August 2020; Published: 17 August 2020 Abstract: To address sustainable development goals (SDGs), national and international strategies have been increasingly interested in the bioeconomy. SDGs have been criticized for lacking stakeholder perspectives and agency, and for requiring too little of business. There is also a lack of both systematic and systemic frameworks for the strategic planning of bioeconomy transitions. Using a systems engineering approach, we seek to address this with a process framework to bridge bioeconomy transitions by addressing SDGs. In this methodology paper, we develop a systems archetype mapping framework for sustainable bioeconomy transitions, called MPAST: Mapping Problem Archetypes to Solutions for Transitions. Using this framework with sector-specific stakeholder data facilitates the establishment of the start (problem state) and end (solution state) to understand and analyze sectorial transitions to the bioeconomy. We apply the MPAST framework to the case of a Norwegian agricultural bioeconomy transition, using data from a survey of the Norwegian agricultural sector on transitioning to a bioeconomy. The results of using this framework illustrate how visual mapping methods can be combined as a process, which we then discuss in the context of SDG implementation. -
Design for Care Innovating Healthcare Experience
Design for Care innovating HealtHCare experienCe Peter H. Jones Rosenfeld Media Brooklyn, New York Design for Care: Innovating Healthcare Experience By Peter H. Jones Rosenfeld Media, LLC 457 Third Street, #4R Brooklyn, New York 11215 USA On the Web: www.rosenfeldmedia.com Please send errors to: [email protected] Publisher: Louis Rosenfeld Developmental Editor: JoAnn Simony Interior Layout Tech: Danielle Foster Cover Design: The Heads of State Indexer: Nancy Guenther Proofreader: Kathy Brock Artwork Designer: James Caldwell, 418QE © 2013 Peter H. Jones All Rights Reserved ISBN: 1-933820-23-3 ISBN-13: 978-1-933820-23-1 LCCN: 2012950698 Printed and bound in the United States of America DeDiCation To Patricia, my own favorite writer, who kept me healthy while writing for three years To my mother, Betsy, whose courage and insight in her recent passing from a rare cancer gives me empathy for the personhood of every patient And to my father, Hayward, whose perpetual resilience shines through after surviving two cancers and living life well How to Use tHis Book Design for Care fuses design practice, systems thinking, and practi- cal healthcare research to help designers create innovative and effective responses to emerging and unforeseen problems. It covers design practices and methods for innovation in patient-centered healthcare services. Design for Care offers best and next practices, and industrial-strength meth- ods from practicing designers and design researchers in the field. Case studies illustrate current health design projects from leading firms, ser- vices, and institutions. Design methods and their applications illustrate how design makes a difference in healthcare today. -
A Memorable Trip Abhisekh Sankaran Research Scholar, IIT Bombay
A Memorable Trip Abhisekh Sankaran Research Scholar, IIT Bombay It was my first trip to the US. It had not yet sunk in that I had been chosen by ACM India as one of two Ph.D. students from India to attend the big ACM Turing Centenary Celebration in San Francisco until I saw the familiar face of Stephen Cook enter a room in the hotel a short distance from mine; later, Moshe Vardi recognized me from his trip to IITB during FSTTCS, 2011. I recognized Nitin Saurabh from IMSc Chennai, the other student chosen by ACM-India; 11 ACM SIG©s had sponsored students and there were about 75 from all over the world. Registration started at 8am on 15th June, along with breakfast. Collecting my ©Student Scholar© badge and stuffing in some food, I entered a large hall with several hundred seats, a brightly lit podium with a large screen in the middle flanked by two others. The program began with a video giving a brief biography of Alan Turing from his boyhood to the dynamic young man who was to change the world forever. There were inaugural speeches by John White, CEO of ACM, and Vint Cerf, the 2004 Turing Award winner and incoming ACM President. The MC for the event, Paul Saffo, took over and the panel discussions and speeches commenced. A live Twitter feed made it possible for people in the audience and elsewhere to post questions/comments which were actually taken up in the discussions. Of the many sessions that took place in the next two days, I will describe three that I found most interesting.