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Hasenjaeger's Electromechanical Small Universal Turing Machine Is
Hasenjaeger's electromechanical small universal Turing machine is time efficient Rainer Glaschick1, Turlough Neary2, Damien Woods3, Niall Murphy4 1Paderborn, Germany 2 Institute for Neuroinformatics, University of Z¨urichand ETH Z¨urich,Switzerland 3 California Institute of Technology, USA c a m p u s 4 MONCLOA Universidad Polit´ecnicade Madrid, CEI Campus Moncloa, UCM-UPM, Madrid, Spain Turing in Context II, October 11, 2012 Glaschick, Neary, Woods, Murphy Hasenjaeger's universal Turing machine is time efficient Summary Hasenjaeger, a (near) contemporary of Turing's Built electromechanical universal Turing machine that was remarkably small Simulated Wang's B-machine (non-erasing machine) We prove that Wang B-machines are a time efficient model of computation (an exponential improvement) As an immediate corollary we find that Hasenjaeger's small machine is efficiently universal Glaschick, Neary, Woods, Murphy Hasenjaeger's universal Turing machine is time efficient Some context 1936 \On Computable Numbers, with an Application to the Entscheidungs problem" Scholz in M¨unsterand Braithwaite in Cambridge requested preprints Scholz was founding a mathematical logic group in M¨unster Undergraduate Hasenjaeger Copyright MFO/CC BY-SA 2.0 Glaschick, Neary, Woods, Murphy Hasenjaeger's universal Turing machine is time efficient Gisbert Hasenjaeger Scholz got him a place in the High Command cryptography group 1942 Hasenjaeger looked for weaknesses in the Enigma machine After the war Hasenjaeger became Scholz's PhD student Became professor of Mathematical logic -
1958: Photopic Field Theory for Natural Hydroso1s
UC San Diego SIO Reference Title Photopic field theory for natural hydroso1s Permalink https://escholarship.org/uc/item/0dk1r645 Author Preisendorfer, Rudolph W Publication Date 1958-09-10 eScholarship.org Powered by the California Digital Library University of California Visibility Laboratory- University of California Scripps Institution of Oceanography San Diego 52, California PHOTIC FIELD THEORY FOR NATURAL HYDROSOLS R. W. Preisendorfer 10 September 1958 Bureau of Ships Index Number NS 714-100 Contract NObs-72092 SIO REFERENCE 58-66 Approved: Approved for Distribution: /£-*.*-'A Seibert Q. Duntley, Director ^—> Roger Revelle, Director Visibility Labora/tory Scripps Institution of Oceanography 1 Photic Field Theory for Natural Hydrosols 2 Rudolph W. Preisendorfer INTRODUCTION The purpose of this note is to present an example of the application of the vector theory of the photic field ("light field") to an important class of scattering-absorbing optical media, namely the class of natural hydrosols consisting, e.g., of oceans, harbors, and lakes. The application is at the same time of practical value in that it yields explicit expressions for the depth-dependence of the light vector in terms of its components at the surface and certain of the optical properties of these media. Furthermore, the discussion presents particularly simple interpretations of the quasipotential and related functions. These interpretations emerge naturally from the geometry and physics of the present application. In this way we add to the evidence that the formalism of the photic field as developed by Moon, Spencer, and others (1), (2), * is of more than academic This paper represents results of research which has been supported by the Bureau of Ships, U. -
L. Maligranda REVIEW of the BOOK by MARIUSZ URBANEK
Математичнi Студiї. Т.50, №1 Matematychni Studii. V.50, No.1 УДК 51 L. Maligranda REVIEW OF THE BOOK BY MARIUSZ URBANEK, “GENIALNI – LWOWSKA SZKOL A MATEMATYCZNA” (POLISH) [GENIUSES – THE LVOV SCHOOL OF MATHEMATICS] L. Maligranda. Review of the book by Mariusz Urbanek, “Genialni – Lwowska Szko la Matema- tyczna” (Polish) [Geniuses – the Lvov school of mathematics], Wydawnictwo Iskry, Warsaw 2014, 283 pp. ISBN: 978-83-244-0381-3 , Mat. Stud. 50 (2018), 105–112. This review is an extended version of my short review of Urbanek's book that was published in MathSciNet. Here it is written about his book in greater detail, which was not possible in the short review. I will present facts described in the book as well as some false information there. My short review of Urbanek’s book was published in MathSciNet [24]. Here I write about his book in greater detail. Mariusz Urbanek, writer and journalist, author of many books devoted to poets, politicians and other figures of public life, decided to delve also in the world of mathematicians. He has written a book on the phenomenon in the history of Polish science called the Lvov School of Mathematics. Let us add that at the same time there were also the Warsaw School of Mathematics and the Krakow School of Mathematics, and the three formed together the Polish School of Mathematics. The Lvov School of Mathematics was a group of mathematicians in the Polish city of Lvov (Lw´ow,in Polish; now the city is in Ukraine) in the period 1920–1945 under the leadership of Stefan Banach and Hugo Steinhaus, who worked together and often came to the Scottish Caf´e (Kawiarnia Szkocka) to discuss mathematical problems. -
NOTE the Theorem on Planar Graphs
HISTORIA MATHEMATICA 12(19X5). 356-368 NOTE The Theorem on Planar Graphs JOHN W. KENNEDY AND LOUIS V. QUINTAS Mathematics Department, Pace University, Pace Plaza, New York, New York, 10038 AND MACEJ M. SYSKO Institute of Computer Science, University of Wroc+aw, ul. Prz,esyckiego 20, 511.51 Wroclow, Poland In the late 1920s several mathematicians were on the verge of discovering a theorem for characterizing planar graphs. The proof of such a theorem was published in 1930 by Kazi- mierz Kuratowski, and soon thereafter the theorem was referred to as the Kuratowski Theorem. It has since become the most frequently cited result in graph theory. Recently, the name of Pontryagin has been coupled with that of Kuratowski when identifying this result. The events related to this development are examined with the object of determining to whom and in what proportion the credit should be given for the discovery of this theorem. 0 1985 AcademicPress. Inc Pendant les 1920s avancts quelques mathkmaticiens &aient B la veille de dCcouvrir un theor&me pour caracttriser les graphes planaires. La preuve d’un tel th6or&me a et6 publiCe en 1930 par Kazimierz Kuratowski, et t6t apres cela, on a appele ce thCor&me le ThCortime de Kuratowski. Depuis ce temps, c’est le rtsultat le plus citC de la thCorie des graphes. Rtcemment le nom de Pontryagin a &e coup16 avec celui de Kuratowski en parlant de ce r&&at. Nous examinons les CvCnements relatifs g ce dCveloppement pour determiner 2 qui et dans quelle proportion on devrait attribuer le mtrite de la dCcouverte de ce th6oreme. -
COMPLEXITY of CURVES 1. Introduction in This Note We Study
COMPLEXITY OF CURVES UDAYAN B. DARJI AND ALBERTO MARCONE Abstract. We show that each of the classes of hereditarily locally connected, 1 ¯nitely Suslinian, and Suslinian continua is ¦1-complete, while the class of 0 regular continua is ¦4-complete. 1. Introduction In this note we study some natural classes of continua from the viewpoint of descriptive set theory: motivations, style and spirit are the same of papers such as [Dar00], [CDM02], and [Kru03]. Pol and Pol use similar techniques to study problems in continuum theory in [PP00]. By a continuum we always mean a compact and connected metric space. A subcontinuum of a continuum X is a subset of X which is also a continuum. A continuum is nondegenerate if it contains more than one point. A curve is a one- dimensional continuum. Let us start with the de¯nitions of some classes of continua: all these can be found in [Nad92], which is our main reference for continuum theory. De¯nition 1.1. A continuum X is hereditarily locally connected if every subcon- tinuum of X is locally connected, i.e. a Peano continuum. A continuum X is hereditarily decomposable if every nondegenerate subcontin- uum of X is decomposable, i.e. is the union of two proper subcontinua. A continuum X is regular if every point of X has a neighborhood basis consisting of sets with ¯nite boundary. A continuum X is rational if every point of X has a neighborhood basis consisting of sets with countable boundary. The following classes of continua were de¯ned by Lelek in [Lel71]. -
Chronik Des Akademischen Jahres 2005/2006
CHRONIK DES AKADEMISCHEN JAHRES 2005/2006 Chronik des Akademischen Jahres 2005/2006 herausgegeben vom Rektor der Rheinischen Friedrich-Wilhelms- Universität Bonn, Prof. Dr. Matthias Winiger, Bonn 2006. Redaktion: Jens Müller, Archiv der Universität Bonn Herstellung: Druckerei der Universität Bonn MATTHIAS WINIGER RHEINISCHE FRIEDRICH-WILHELMS-UNIVERSITÄT BONN Chronik des Akademischen Jahres 2005/06 Bonn 2006 Jahrgang 121 Neue Folge Jahrgang 110 INHALTSVERZEICHNIS Rede des Rektors zur Eröffnung des Akademischen Jahres Rückblick auf das Akademische Jahr 2005/06 .....S. 9 Preisverleihungen und Ehrungen Preisverleihungen und Ehrungen im Akademischen Jahr 2005/06 ...........................S. 23 Akademischer Festvortrag Wilhelm Barthlott, Biodiversität als Herausforderung und Chance.................................S. 25 Chronik des Akademischen Jahres Das Akademische Jahr 2005/06 in Pressemeldungen..............................................S. 40 Nachrufe ......................................................................S. 54 Berichte aus den Fakultäten Evangelisch-Theologische Fakultät ....................S. 67 Katholisch-Theologische Fakultät ......................S. 74 Rechts- und Staatswissenschaftliche Fakultät S. 83 Medizinische Fakultät ............................................S. 103 Philosophische Fakultät .........................................S. 134 Mathematisch-Naturwissenschaftliche Fakultät.......S. 170 Landwirtschaftliche Fakultät ..................................S. 206 Beitrag zur Universitätsgeschichte Thomas Becker, -
L. Maligranda REVIEW of the BOOK by ROMAN
Математичнi Студiї. Т.46, №2 Matematychni Studii. V.46, No.2 УДК 51 L. Maligranda REVIEW OF THE BOOK BY ROMAN DUDA, “PEARLS FROM A LOST CITY. THE LVOV SCHOOL OF MATHEMATICS” L. Maligranda. Review of the book by Roman Duda, “Pearls from a lost city. The Lvov school of mathematics”, Mat. Stud. 46 (2016), 203–216. This review is an extended version of my two short reviews of Duda's book that were published in MathSciNet and Mathematical Intelligencer. Here it is written about the Lvov School of Mathematics in greater detail, which I could not do in the short reviews. There are facts described in the book as well as some information the books lacks as, for instance, the information about the planned print in Mathematical Monographs of the second volume of Banach's book and also books by Mazur, Schauder and Tarski. My two short reviews of Duda’s book were published in MathSciNet [16] and Mathematical Intelligencer [17]. Here I write about the Lvov School of Mathematics in greater detail, which was not possible in the short reviews. I will present the facts described in the book as well as some information the books lacks as, for instance, the information about the planned print in Mathematical Monographs of the second volume of Banach’s book and also books by Mazur, Schauder and Tarski. So let us start with a discussion about Duda’s book. In 1795 Poland was partioned among Austria, Russia and Prussia (Germany was not yet unified) and at the end of 1918 Poland became an independent country. -
L. Maligranda REVIEW of the BOOK BY
Математичнi Студiї. Т.50, №1 Matematychni Studii. V.50, No.1 УДК 51 L. Maligranda REVIEW OF THE BOOK BY MARIUSZ URBANEK, “GENIALNI – LWOWSKA SZKOL A MATEMATYCZNA” (POLISH) [GENIUSES – THE LVOV SCHOOL OF MATHEMATICS] L. Maligranda. Review of the book by Mariusz Urbanek, “Genialni – Lwowska Szko la Matema- tyczna” (Polish) [Geniuses – the Lvov school of mathematics], Wydawnictwo Iskry, Warsaw 2014, 283 pp. ISBN: 978-83-244-0381-3 , Mat. Stud. 50 (2018), 105–112. This review is an extended version of my short review of Urbanek's book that was published in MathSciNet. Here it is written about his book in greater detail, which was not possible in the short review. I will present facts described in the book as well as some false information there. My short review of Urbanek’s book was published in MathSciNet [24]. Here I write about his book in greater detail. Mariusz Urbanek, writer and journalist, author of many books devoted to poets, politicians and other figures of public life, decided to delve also in the world of mathematicians. He has written a book on the phenomenon in the history of Polish science called the Lvov School of Mathematics. Let us add that at the same time there were also the Warsaw School of Mathematics and the Krakow School of Mathematics, and the three formed together the Polish School of Mathematics. The Lvov School of Mathematics was a group of mathematicians in the Polish city of Lvov (Lw´ow,in Polish; now the city is in Ukraine) in the period 1920–1945 under the leadership of Stefan Banach and Hugo Steinhaus, who worked together and often came to the Scottish Caf´e (Kawiarnia Szkocka) to discuss mathematical problems. -
Arxiv:1803.01386V4 [Math.HO] 25 Jun 2021
2009 SEKI http://wirth.bplaced.net/seki.html ISSN 1860-5931 arXiv:1803.01386v4 [math.HO] 25 Jun 2021 A Most Interesting Draft for Hilbert and Bernays’ “Grundlagen der Mathematik” that never found its way into any publi- Working-Paper cation, and 2 CVof Gisbert Hasenjaeger Claus-Peter Wirth Dept. of Computer Sci., Saarland Univ., 66123 Saarbrücken, Germany [email protected] SEKI Working-Paper SWP–2017–01 SEKI SEKI is published by the following institutions: German Research Center for Artificial Intelligence (DFKI GmbH), Germany • Robert Hooke Str.5, D–28359 Bremen • Trippstadter Str. 122, D–67663 Kaiserslautern • Campus D 3 2, D–66123 Saarbrücken Jacobs University Bremen, School of Engineering & Science, Campus Ring 1, D–28759 Bremen, Germany Universität des Saarlandes, FR 6.2 Informatik, Campus, D–66123 Saarbrücken, Germany SEKI Editor: Claus-Peter Wirth E-mail: [email protected] WWW: http://wirth.bplaced.net Please send surface mail exclusively to: DFKI Bremen GmbH Safe and Secure Cognitive Systems Cartesium Enrique Schmidt Str. 5 D–28359 Bremen Germany This SEKI Working-Paper was internally reviewed by: Wilfried Sieg, Carnegie Mellon Univ., Dept. of Philosophy Baker Hall 161, 5000 Forbes Avenue Pittsburgh, PA 15213 E-mail: [email protected] WWW: https://www.cmu.edu/dietrich/philosophy/people/faculty/sieg.html A Most Interesting Draft for Hilbert and Bernays’ “Grundlagen der Mathematik” that never found its way into any publication, and two CV of Gisbert Hasenjaeger Claus-Peter Wirth Dept. of Computer Sci., Saarland Univ., 66123 Saarbrücken, Germany [email protected] First Published: March 4, 2018 Thoroughly rev. & largely extd. (title, §§ 2, 3, and 4, CV, Bibliography, &c.): Jan. -
Leaders of Polish Mathematics Between the Two World Wars
COMMENTATIONES MATHEMATICAE Vol. 53, No. 2 (2013), 5-12 Roman Duda Leaders of Polish mathematics between the two world wars To Julian Musielak, one of the leaders of post-war Poznań mathematics Abstract. In the period 1918-1939 mathematics in Poland was led by a few people aiming at clearly defined but somewhat different goals. They were: S. Zaremba in Cracow, W. Sierpiński and S. Mazurkiewicz in Warsaw, and H. Steinhaus and S. Banach in Lvov. All were chairmen and editors of mathematical journals, and each promoted several students to continue their efforts. They were highly successful both locally and internationally. When Poland regained its independence in 1918, Polish mathematics exploded like a supernova: against a dark background there flared up, in the next two deca- des, the Polish Mathematical School. Although the School has not embraced all mathematics in the country, it soon attracted common attention for the whole. Ho- wever, after two decades of a vivid development the School ended suddenly also like a supernova and together with it there silenced, for the time being, the rest of Polish mathematics. The end came in 1939 when the state collapsed under German and Soviet blows from the West and from the East, and the two occupants cooperated to cut short Polish independent life. After 1945 the state and mathematics came to life again but it was a different state and a different mathematics. The aim of this paper is to recall great leaders of the short-lived interwar Polish mathematics. By a leader we mean here a man enjoying an international reputation (author of influential papers or monographs) and possessing a high position in the country (chairman of a department of mathematics in one of the universities), a man who had a number of students and promoted several of them to Ph.D. -
ABSTRACT XUE, XIANGZHONG. Electronic
ABSTRACT XUE, XIANGZHONG. Electronic System Optimization Design via GP-Based Surrogate Modeling. (Under the direction of Dr. Paul D. Franzon.) For an electronic system with a given circuit topology, the designer’s goal is usually to automatically size the device and components to achieve globally optimal performance while at the same satisfying the predefined specifications. This goal is motivated by a human desire for optimality and perfection. This research project improves upon current optimization strategies. Many types of convex programs and convex fitting techniques are introduced and compared, and the evolution of Geometric Program (GP)-based optimization approaches is investigated through a literature review. By these means, it is shown that a monomial-based GP can achieve optimal performance and accuracy only for long-channel devices, and that a piecewise linear (PWL)-based GP works well only for short-channel, narrow devices without many data fitted. Based on known GP optimizer and convex PWL fitting techniques, an innovative surrogate modeling and optimization algorithm is proposed to further improve performance accuracy iteratively for a wide transistor with a short channel. The new surrogate strategy, which comprises a fine model and a coarse model, can automatically size the device to create a reusable system model for designing electronic systems and noticeably improving prediction accuracy, particularly when compared to the pure, GP-based optimization method. To verify the effectiveness and viability of the proposed surrogate strategy, a widely used two-stage optimization design is employed, entailing an operational amplifier (op-amp) and LC-tuned oscillator. In addition, an involved analysis and simulation demonstrate that the optimal results of both coarse and fine models in the proposed surrogate strategy may gradually converge to each other iteratively while achieving over 10% improvement in performance accuracy compared to the previous, PWL-based GP algorithm. -
A Geometry Oã-Nutrition1
A Geometry oÃNutrition1 PARRY MOON AND DOMINA EBERLE SPENCER Electrical Engineering Department, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, and Mathematics Department, University of Connecticut, Starrs, Connecticut 06268 ABSTRACT The nutritional value of a given sample of food may be specified by a nutrition holor in a fictitious 3-space. This holor possesses magnitude and character. In most cases, we are interested primarily in character, and this can be represented by a point in a 2-space (the nutrition triangle). The triangle allows visualization of re lations among foods and also the addition of nutritional values for a combination of foods. J. Nutr. 104: 1535-1542, 1974. INDEXING KEY WORDS geometry •mathematical model •nutrient patterns Downloaded from The worldwide importance of modern acter of a food may be specified by giving nutritional theory can hardly be overesti any two of the above coordinates. These mated. Nutrition calculations, however, coordinates can be plotted in a nutrition have remained in the arithmetic stage and triangle (fig. 1). have not utilized the possibilities of alge The diagram is advantageous because it braic and geometric formulation. In par shows at a glance the relations among jn.nutrition.org ticular, a geometrization of nutrition al foods: which food has the higher lipid lows one to visualize the relations among content, which has the more protein, etc. nutrients and thus to bypass much of the The triangle can be divided into regions. present routine computation, in accordance Sugars, syrups, and honey are almost pure with the principle that a picture is worth carbohydrate, so they are represented by by on November 25, 2009 a thousand words.