An Evening Wasted with Tom Lehrer is an album recorded by Tom Lehrer, the well-known satirist and Harvard lecturer. The recording was made on March 20–21, 1959 in Sanders Theater at Harvard.

In October 2020, Lehrer transferred the music and lyrics for all songs he had ever written into the public domain. In November 2022, he formally relinquished the copyright and performing/recording rights on his songs, making all music and lyrics composed by him free for anyone to use.

Track listing
"Poisoning Pigeons in the Park" – 2:38
"Bright College Days" – 3:03
"A Christmas Carol" – 2:54
"The Elements" – 2:16
"Oedipus Rex" – 3:41
"In Old Mexico" – 6:26
"Clementine" – 4:40
"It Makes a Fellow Proud to Be a Soldier" – 4:50
"She's My Girl" – 2:53
"The Masochism Tango" – 3:30
"We Will All Go Together When We Go" – 5:32

Songs' sources

"Poisoning Pigeons in the Park"
The lyrics refer to killing pigeons with cyanide-coated peanuts and strychnine-treated corn. The latter method was used by the United States Fish and Wildlife Service to control pigeon populations in Boston public areas during the 1950s. The pianist hired for an orchestral version of the song, arranged and conducted by Richard Hayman with vocals by Lehrer, fell off his bench when he heard the title.

"Bright College Days"
This song borrows heavily from "The Whiffenpoof Song", the traditional signature song of the Yale Whiffenpoofs.

"The Elements"

The lyrics of "The Elements" are a recitation of the names of all the chemical elements that were known at the time of writing, up to number 102, nobelium. It can be found on his albums Songs & More Songs by Tom Lehrer as well as An Evening Wasted with Tom Lehrer. The song is sung to the tune of Sir Arthur Sullivan's "Major General's Song" ("I am the very model of a modern major-general...") from The Pirates of Penzance.  Since that time, 16 more have been discovered. At his concert in Copenhagen (1967), Lehrer admitted, "I like to play this song every once in a while, just to see if I can still do it!" Indeed, several of Lehrer's fans, such as actor Daniel Radcliffe, have tried and failed to sing it. That is, he sang it in its entirety, but with slight hiccups. At some concerts he also played a version he claims is based on Aristotle's elements: "There's earth and air and fire and water."

"Oedipus Rex"
Lehrer comments that most popular movies of the time have a catchy title song that helps to draw in audiences. Believing that a recent (1957) film adaptation of Sophocles' play Oedipus Rex had failed at the box office because it did not have such a song, he wrote this one in ragtime style. It was also a reference to the popularity of Freudian psychoanalysis and the Oedipus complex in popular culture in the 1940s and 1950 in the United States.

"In Old Mexico"
This song is prefaced by a lengthy commentary about the (fictional) Dr. Samuel Gall, who gained fame and fortune from his "invention" of the gallbladder. Performed in the style of Mexican folk music, it describes the narrator's memory of a trip to that country and his viewing of a bullfight. The lyrics refer to three famous Spanish bullfighters, Belmonte, Dominguín, and Manolete, and also include a pejorative reference to Mexico as "the land of the wetback."

"Clementine"
"Clementine" is a parody of the old folk song "Oh My Darling, Clementine" as it might have turned out had it had been written by various composers in widely different styles of music. The first verse was in the style of Cole Porter (suggestive of "Night and Day"); the second verse an aria for baritone in the style of Mozart "or one of that crowd"; the third verse in the style of the Beatnik "Cool School" (suggestive of Thelonious Monk's "52nd Street Theme"); and the rousing finale was, in Lehrer's paraphrase of Shakespeare, "full of words and music, and signifying nothing," in the style of Gilbert and Sullivan (suggestive of "My name is John Wellington Wells" or other patter songs). Lehrer's argument for rewriting the song is that folk songs in general are "so atrocious, because they're written 'by the people'," and that the original "Clementine" has "no recognizable merit whatsoever."

"It Makes a Fellow Proud to Be a Soldier"
A parody of the official songs in use by the various branches of the United States military. Lehrer explains that the Army "didn't have no official song" when he started basic training; he wrote this one in an attempt to remedy the situation. (The branch adopted "The Army Goes Rolling Along" as its song in 1956, one year after Lehrer enlisted.)

One of the rare parodies of Lehrer's work emerged in Jim Bouton's classic book Ball Four: "It Makes a Fellow Proud to be an Astro", conjured up by members of the 1969 Houston Astros.

Notes

Tom Lehrer albums
1959 live albums
Reprise Records live albums
Warner Records live albums
Satirical works
1950s comedy albums
Live comedy albums
Albums free for download by copyright owner

An Evening Wasted with Tom Lehrer


A Sparse graph code is a code which is represented by a sparse graph.

Any linear code can be represented as a graph, where there are two sets of nodes - a set representing the transmitted bits and another set representing the constraints that the transmitted bits have to satisfy. The state of the art classical error-correcting codes are based on sparse graphs, achieving close to the Shannon limit. The archetypal sparse-graph codes are Gallager's low-density parity-check codes.

External links
 The on-line textbook: Information Theory, Inference, and Learning Algorithms, by David J.C. MacKay, discusses sparse-graph codes in Chapters 47–50.
Encyclopedia of Sparse Graph Codes
 Iterative Error Correction: Turbo, Low-Density Parity-Check, and Repeat-Cccumulate Codes

Matrix theory
Error detection and correction

Sparse graph code


Panmunjom (Hangul: 판문점, Hanja: 板門店, McCune-Reischauer: P'anmunjŏm, revideret romanisering: Panmunjeom) er en landsby som ligger på de facto-grænsen mellem Nord og Sydkorea. I 1953 blev våbenhvileaftalen, som gjorde en ende på Koreakrigen, underskrevet her.

Bygningen, hvor aftalen blev underskrevet, står fortsat der, hvor den blev bygget, lige nord for grænselinjen, som går midt i den demilitariserede zone.

Grænsen er anset som en af de sidste rester fra den kolde krig. Samtaler mellem nord- og sydkoreanske myndigheder foregår i de lyseblå bygninger, som er beliggende i Panmunjom.

Lokalisering
Landsbyen ligger 48 kilometer nordvest for den sydkoreanske hovedstad Seoul og 10 kilometer øst for den nordkoreanske by Kaesong og var åsted for møderne til den militære våbenhvilekommission de sidste år af Koreakrigen.

De første møder blev først afholdt i telt på den sydlige side af vejen mellem Kaesong og Seoul på vestbredden af floden Sa'cheon. Landsbyen, som bestod af under ti små hytter, lå på den nordkoreanske side af vejen.

Bygningen blev konstrueret af begge sider i løbet af 48 timer. Nordkorea bidrog med arbejdskraft og nogen vareleverancer, FN-kommandoen bidrog med vareleverancer, generatorer og lys, hvilket gjorde det muligt også at arbejde om natten.

De ledende delegater fra hver side brugte 10 minutter på at underskrive de 18 kopier af aftalens to dele på tre sprog.

Efter, at våbenhvileaftalen var underskrevet, blev der i september 1953 igangsat arbejde med at etablere et permanent mødested vel en kilometer øst for landsbyen. Området blev kaldt Joint Security Area (JSA = fælles sikkerhedsområde), og det er der, alle møderne mellem Nordkorea og FN-kommandoen eller Sydkorea er foregået siden. JSA bliver ofte kaldt for Panmunjom, hvilket altså ikke er korrekt.

Efter krigen blev alle civile flyttet fra den demilitariserede zone med undtagelse af to landsbyer, en på hver side af grænsen. Landsbyen Panmunjom forfaldt langsomt men sikkert og er i dag helt borte. Bygningen, som blev benyttet for at underskrive våbenhvileaftalen, er senere døbt til Fredsmuseet af Nordkorea.

Baggrund
De lille landsby Panmunjom var åsted for forhandlingerne, som førte til, at Koreakrigen standsede. Repræsentanter fra FN-kommandoen mødte nordkoreanske og kinesiske repræsentanter fra 1951 til 1953. Samtalerne trak ud flere måneder, eftersom parterne var uenige om både militære grænser og hvordan krigsfangerne skulle behandles, og det var særlig løsningen på det sidste spørgsmål, som tog tid.

Soldater under FN-kommando, som blev taget til fange af Nordkorea, blev i stor udstrækning mishandlet og udsatte for hjernevask. For Nordkorea og Kina var problemet anderledes. Over en trediedel af krigsfangerne, som FN-kommandoen havde taget til fange, og et større antal kinesere ville ikke sendes tilbage til sine hjemlande. Sydkorea stod tillige fast på, at Korea skulle genforenes.

Den 8. juni 1953 blev krigsfangeproblemet løst. De fanger, som nægtede at vende tilbage til deres oprindelige hjemland, blev givet mulighed for at leve under neutral overvågning i tre måneder. Så skulle de, som fortsat nægtede at blive sendt tilbage, blive sat fri.

Den endelige aftale blev underskrevet den 27. juli 1953. USA, Kina og Nordkorea kom til enighed om en våbenhvile, som satte en stopper for kamphandlingerne, men Sydkorea nægtede at skrive under.

Aftalen sagde blandt andet, at der skulle oprettes en fire kilometer bred demilitariseret zone over den koreanske halvø, som mere eller mindre fulgte den 38. breddegrad. Tropper og våben skulle fjernes fra området, som var blevet stærkt befæstet mod slutningen af krigen. Eftersom Sydkorea nægtede at underskrive aftalen, er de to koreanske nationer fortsat, teknisk set, i krig.

USA har haft soldater stationerede i Sydkorea siden 2. verdenskrig. I november 2004 startede tilbagetrækningen af vel en trediedel af styrken. Samtidig blev de amerikanske soldaters hovedkvarter i Panmunjom lagt ned, og amerikanske soldaters patruljering langs grænsen mod Nordkorea, ophørte.

Hændelser

Panmunjom er i centrum af et af verdens militært og politisk set mest spændte områder. Stedet har været åsted for flere hændelser, som har afstedkommet international opmærksomhed:
 Den 18. august 1976, klokken 1040. En gruppe på fem civilt ansatte sydkoreanere skal sammen med en sikkerhedsstyrke fra FN-kommandoen inkluderet major Arthur G. Bonifas (også leder for FN-kommandoen i JSA), løjtnant Mark T. Barrett samt en officer fra den sydkoreanske hær (ROKA), fælde et stort træ, som forhinder udsigten mellem to FN-vagtposter. De bliver pludselig angrebet af nordkoreanske grænsevagter.

Vagtposten, som skal få bedre udsigt ligger lige ved "Bridge of No Return", som fik sit navn, da frigivne nordkoreanske krigsfanger, som ville vende tilbage til Nordkorea, måtte gå over denne bro for at komme hjem. Grænsen mellem de to koreanske nationer ligger halvvejs ude på broen. De nordkoreanske soldater havde gjort flere forsøg tidligere på tage personel under FN-kommandoen til fange og over på nordkoreansk side.

Kampene, som så fulgte, involverede 30 nordkoreanske soldater og 14 soldater tilhørende FN-kommandoen. Bonifas og Barrett blev dræbte af nordkoreanske soldater, som brugte økser og knive, som de flygtende sydkoreanere kastede fra sig.

 Den 21. august 1976, klokken 0700. FN-kommandoen iscenesætter en gigantisk militær parade, Operation Paul Bunyan, for at understrege kommandoens ret til at operere frit og indenfor våbenhvileaftalen på deres egen side af DMZ.

 Den 23. december 1968. Besætningen om bord i det amerikanske spionskib U.S.S. Pueblo gik over Bridge of No Return til Sydkorea, da de blev sat fri efter 11 måneders fangenskab.

 Et antal afhopninger er også sket over årene, således gik en kaptajn i Nordkoreas hær over grænsen mod Sydkorea den 3. februar 1998.

 En nordkoreansk tunnel konstrueret for at infiltrere og muligvis invadere Sydkorea, blev fundet vel 4 mil sydsydvest for Panmunjom i 1978. Senere blev tre andre tunneler fundet langs DMZ, hvoraf en stor nok til at køre biler igennom, den seneste i 1990-erne.

Eksterne henvisninger
 Travel in Korea: Panmunjeom information about the village and its history.
 Den kalde krigens siste skanse  (Aftenposten)
 På grensen til det uforståelige  (Forsvarets Forum)
 Den siste grensa (Dagbladet)

Koreakrigen

Panmunjom


Søren Frichs Vej i Aarhus ligger mellem Vestre Ringgade og Viby Ringvej. Mod syd følger vejen Brabrandstien.

Gaden fik officielt navnet "Søren Frichs Vej" på byrådsmødet den 20. oktober 1921, et forslag som Udvalget for Byens Udvidelse og Bebyggelse indstillede og efterfølgende blev vedtaget af Aarhus Byråd.

Vejen er opkaldt efter Søren Frich, som oprettede A/S Frichs Maskinfabrik og Kedelsmedie. Firmaet flyttede til vejen omkring 1908. Flere af fabrikkens gamle bygninger kan stadig ses på området og kan kendes ved deres karakteristiske gule farve.

Kilder og henvisninger

Gader i Aarhus

Søren Frichs Vej


Uszód é um município da Hungria, situado no condado de Bács-Kiskun. Tem  de área e sua população em 2015 foi estimada em 922 habitantes.

Localidades de Bács-Kiskun

Uszód


Beyköy, Samsun ilinin Kavak ilçesine bağlı bir mahalledir.

Tarihçe
Tarih tam olarak bilinmese de, Kavak ilçesinde yerleşilen ilk köy olduğu ve buradan diğer köylere göç edildiği bilinmektedir.

Coğrafya
Samsun iline 55 km, Kavak ilçesine 10 km uzaklıktadır.

Nüfus

Kavak'ın mahalleleri

Beyköy, Kavak


Yakov Borisovich Zeldovich  (, ; 8 March 1914 – 2 December 1987), also known as YaB,  was a leading Soviet physicist of Belarusian origin, who is known for his prolific contributions in physical cosmology, physics of thermonuclear reactions, combustion, and hydrodynamical phenomena.

From 1943, Zeldovich, a self-taught physicist, started his career by playing a crucial role in the development of the former Soviet program of nuclear weapons. In 1963, he returned to academia to embark on pioneering contributions on the fundamental understanding of the thermodynamics of black holes and expanding the scope of physical cosmology.

Biography

Early life and education

Yakov Zeldovich was born into a Belarusian Jewish family in his grandfather's house in Minsk. However, in mid-1914, the Zeldovich family moved to Saint Petersburg. They resided there until August 1941, when the family was evacuated together with the faculty of the Institute of Chemical Physics to Kazan to avoid the Axis Invasion of the Soviet Union. They remained in Kazan until the summer of 1943, when Zeldovich moved to Moscow.

His father, Boris Naumovich Zeldovich, was a lawyer; his mother, Anna Petrovna Zeldovich (née Kiveliovich), a translator from French to Russian, was a member of the Writer's Union. Despite being born into a devoted and religious Jewish family, Zeldovich was an "absolute atheist".

Zeldovich was an autodidact. He was regarded as having a remarkably versatile intellect, and during his life he explored and made major contributions to a wide range of scientific endeavors. From a given opportunity in May 1931, he secured an appointment as a laboratory assistant at the Institute of Chemical Physics of the Academy of Sciences of the Soviet Union, and remained associated with the institute for the remainder of his life. As a laboratory assistant, he received preliminary instructions on the topics involved in the physical chemistry and built up his reputation among his seniors at the Institute of Chemical Physics.

From 1932 to 1934, Zeldovich attended the undergraduate courses on physics and mathematics at the Leningrad State University (now Saint Petersburg State University), and later attended the technical lectures on introductory physics at the Leningrad Polytechnic Institute (now Peter the Great St. Petersburg Polytechnic University).

In 1936, he was successful in his candidacy for the Candidate of Science degree (a Soviet equivalent of PhD), having successfully defended his dissertation on the topic of the "adsorption and catalysis on heterogeneous surfaces". The centrality of his thesis focused towards the research on the Freundlich (or classical) adsorption isotherm, and Zeldovich discovered the theoretical foundation of this empirical observation.

In 1939, Zeldovich prepared his dissertation based on the mathematical theory of the physical interpretation of nitrogen oxidation, and successfully received the Doctor of Sciences in mathematical physics when it was reviewed by Alexander Frumkin. Zeldovich discovered its mechanism, known in physical chemistry as the thermal  mechanism or Zeldovich mechanism.

Soviet program of nuclear weapons

Zeldovich is regarded as a secret principal of the Soviet nuclear weapons project; his travels abroad were highly restricted, to Eastern Europe, under close Soviet security. Soon after the discovery of nuclear fission (by German chemist Otto Hahn in 1939) Russian physicists had begun investigating the scope of nuclear-fission physics, and undertook seminars on that topic; Igor Kurchatov and Yulii Khariton were engaged in 1940.

In May 1941, Zeldovich worked with Khariton in constructing a theory, on the kinetics of nuclear reactions in the presence of the critical conditions. The work of Khariton and Zeldovich was extended into theories of ignition, combustion and detonation; these accounted for features which had not previously been correctly predicted, observed, nor explained. The modern theory of detonation accordingly is called the Zeldovich-von Neumann-Dohring, or ZND, theory, and its development involved tedious fast neutron calculations; this work had been delayed, due to the German invasion of the Soviet Union, which obstructed progress on findings that in June 1941 would be de-classified. In 1942, Zeldovich was relocated to Kazan, and tasked by the People's Commissariat of Munitions to carry out work on conventional gun powders to be supplied to the Soviet Army, while Khariton was asked to design the new types of conventional weaponry.

In 1943, Joseph Stalin decided to launch an arms build-up of nuclear weapons, under the charge of Igor Kurchatov; the latter requested Stalin to relocate Zeldovich and Khariton to Moscow, in the nuclear weapons program. Zeldovich joined Igor Kurchatov's small team at this secretive laboratory in Moscow to launch the work on the nuclear combustion theory, and became a head of the theoretical department at the Arzamas-16 in 1946.

With Isaak Gurevich, Isaak Pomeranchuk, and Khariton, Zeldovich prepared a scientific report on the feasibility of releasing energy through nuclear fusion triggered by an atomic explosion, and presented it to Igor Kurchatov. Zeldovich had benefitted from physical and technical knowledge provided by German physicist Klaus Fuchs and American physicist Theodore Hall, who each had worked on the American Manhattan Project to develop nuclear weapons.

In 1949, Zeldovich led a team of physicists that conducted the first nuclear test, the RDS-1, based roughly on the American design obtained through the atomic spies in the United States, though he continued his fundamental work on explosive theory. Zeldovich then began working on modernizing the successive designs of the nuclear weapon and initially conceived the idea of hydrogen bomb to Andrei Sakharov and others. In the course of his work on nuclear weapons, Zeldovich did ground-breaking work in radiation hydrodynamics, and the physics of matter at high pressure.

Between 1950 and 1953, Zeldovich performed calculations necessary for the feasibility of the hydrogen bomb that were verified by Andrei Sakharov, although the two groups worked in parallel on the development of the thermonuclear fusion. However, it was Sakharov that radically changed the approach to thermonuclear fusion, aided by Vitaly Ginzburg in 1952. He remained associated with the nuclear testing program, while heading the experimental laboratories at Arzamas-16 until October 1963, when he left for academia.

Academia and cosmology

In 1952, Zeldovich began work in the field of elementary particles and their transformations. He predicted the beta decay of a pi meson. Together with Semyon Gershtein he noticed the analogy between the weak and electromagnetic interactions, and in 1960, he predicted the muon catalysis (more precisely, the muon-catalysed dt-fusion) phenomenon. In 1977, Zeldovich together with  was awarded the Kurchatov Medal, the highest award in nuclear physics of the Soviet Union. The citation was "for prediction of characteristics of ultracold neutrons, their detection and investigation". He was elected academician of the USSR Academy of Sciences on 20 June 1958. He was a head of division at the Institute of the Applied Mathematics of the USSR Academy of Sciences from 1965 until January 1983.

In early 1960s, Zeldovich started working in astrophysics and physical cosmology. In 1964, he and independently Edwin Salpeter were the first to suggest that accretion discs around massive black holes are responsible for the huge amounts of energy radiated by quasars. From 1965, he was a professor at the Department of Physics of the Moscow State University and a head of the division of Relativistic Astrophysics at the Sternberg Astronomical Institute. In 1966, he and Igor Novikov were the first to propose searching for black hole candidates among binary systems in which one star is optically bright and X-ray dark and the other optically dark but X-ray bright (the black hole candidate).

Zeldovich worked on the theory of the evolution of the hot universe, the properties of the microwave background radiation, the large-scale structure of the universe, and the theory of black holes. He predicted, with Rashid Sunyaev, that the cosmic microwave background should undergo inverse Compton scattering. This is called the Sunyaev-Zeldovich effect, and measurements by telescopes such as the Atacama Cosmology Telescope and the South Pole Telescope has established it as one of the key observational probes of cluster cosmology. Zeldovich contributed sharp insights into the nature of the large scale structure of the universe, in particular, through the use of Lagrangian perturbation theory (the Zeldovich approximation) and the application of the Burgers' equation approach via the adhesion approximation.

In 1974, in collaboration with A. G. Polnarev, suggested the existence of a gravitational memory effect, for which a system of freely falling particles initially at relative rest are displaced after the passing of a burst of gravitational radiation.

Black hole thermodynamics

Zeldovich played a key role in developing the theory of black hole evaporation due to Hawking radiation. Zeldovich and Charles W. Misner concomitantly predicted the possibility of particle generation by rotating Kerr black holes in 1971, 1972. Previously, In 1965, Zeldovich had predicted that Kerr black holes would split the emission lines of photons as in a Zeeman effect. During Stephen Hawking's visit to Moscow in 1973, Soviet scientists Zeldovich and Alexei Starobinsky showed Hawking that, according to the quantum mechanical uncertainty principle, rotating black holes should create and emit particles.

Family
With his wife, Varvara Pavlovna Konstantinova, Yakov Zeldovich had a son and two daughters who were also physicists: son – Boris Zeldovich; daughters – Olga Yakovlevna Zeldovich and Marina Yakovlevna Zeldovich.

Zeldovich also had a daughter, Annushka, with O.K. Shiryaeva.

He had one more daughter in 1945, Alexandra Varkovitskaya, with a linguist and folklorist Ludmila Varkovitskaya.

Zeldovich had another son with Nina Nikolaevna Agapova in 1958, whose name was Leonid Yakovlevich Agapov; he died in 2016 at the age of 58.

Publications

Books

Awards and honors

Igor Kurchatov called him a "genius" and Andrei Sakharov named him "a man of universal scientific interests." After the first meeting in Moscow, Stephen W. Hawking wrote to Zeldovich: "now I know that you are a real person and not a group of scientists like Bourbaki." He was a member of the American Academy of Arts and Sciences (1975), the United States National Academy of Sciences (1979), and the American Philosophical Society (1979).

Dirac Medal of the ICTP (1985)
Bruce Medal (1983)
Gold Medal of the Royal Astronomical Society (1984).
Kurchatov Medal (1977)
Three times Hero of Socialist Labor (1949, 1953, 1957)
Stalin Prize (1943, 1949, 1951, 1953)
Lenin Prize (1957)
Three Orders of Lenin (1949, 1962, 1974)
Two Orders of the Red Banner of Labour (1945,1964)
Order of the October Revolution (1962)
An asteroid  11438 Zeldovich was named in his honor in 2001.

References

Further reading
 Overbye, D. Lonely Hearts of the Cosmos: The Scientific Quest for the Secret of the Universe. New York: HarperCollins, 1991.
 Annotated Bibliography for Yakov Borisovich Zel'dovich from the Alsos Digital Library for Nuclear Issues
 Yakov Borisovich Zel'dovich – page at the Moscow State University dedicated to Zeldovich
 Theory of combustion of unmixed gases – Zeldovich 1949, translated 1974

External links

1914 births
1987 deaths
Scientists from Minsk
Foreign associates of the National Academy of Sciences
Foreign Members of the Royal Society
Full Members of the USSR Academy of Sciences
Academic staff of Moscow State University
Nuclear weapons program of the Soviet Union
Heroes of Socialist Labour
Recipients of the Stalin Prize
Recipients of the Lenin Prize
Recipients of the Bruce Medal
Recipients of the Gold Medal of the Royal Astronomical Society
Recipients of the Order of Lenin
Recipients of the Order of the Red Banner of Labour
Belarusian atheists
Belarusian Jews
Soviet astronomers
Belarusian astronomers
Soviet cosmologists
Fluid dynamicists
Jewish atheists
Jewish scientists
Particle physicists
Soviet inventors
Belarusian inventors
Jewish physicists
Members of the American Philosophical Society
Russian scientists

Yakov Zeldovich


In computer science, random-access machine (RAM) is an abstract machine in the general class of register machines. The RAM is very similar to the counter machine but with the added capability of 'indirect addressing' of its registers. Like the counter machine, The RAM has its instructions in the finite-state portion of the machine (the so-called Harvard architecture).

The RAM's equivalent of the universal Turing machinewith its program in the registers as well as its datais called the random-access stored-program machine or RASP. It is an example of the so-called von Neumann architecture and is closest to the common notion of a computer.

Together with the Turing machine and counter-machine models, the RAM and RASP models are used for computational complexity analysis. Van Emde Boas (1990) calls these three plus the pointer machine "sequential machine" models, to distinguish them from "parallel random-access machine" models.

Introduction to the model
The concept of a random-access machine (RAM) starts with the simplest model of all, the so-called counter machine model. Two additions move it away from the counter machine, however. The first enhances the machine with the convenience of indirect addressing; the second moves the model toward the more conventional accumulator-based computer with the addition of one or more auxiliary (dedicated) registers, the most common of which is called "the accumulator".

Formal definition
A random-access machine (RAM) is an abstract computational-machine model identical to a multiple-register counter machine with the addition of indirect addressing. At the discretion of instruction from its finite state machine's TABLE, the machine derives a "target" register's address either (i) directly from the instruction itself, or (ii) indirectly from the contents (e.g. number, label) of the "pointer" register specified in the instruction.

By definition: A register is a location with both an address (a unique, distinguishable designation/locator equivalent to a natural number) and a contenta single natural number. For precision we will use the quasi-formal symbolism from Boolos-Burgess-Jeffrey (2002) to specify a register, its contents, and an operation on a register:
 [r] means "the contents of register with address r". The label "r" here is a "variable" that can be filled with a natural number or a letter (e.g. "A") or a name.
 → means "copy/deposit into", or "replaces", but without destruction of the source
 Example: [3] +1 → 3; means "The contents of source register with address "3", plus 1, is put into destination register with address "3" (here source and destination are the same place). If [3]=37, that is, the contents of register 3 is the number "37", then 37+1 = 38 will be put into register 3.

 Example: [3] → 5; means "The contents of source register with address "3" is put into destination register with address "5". If [3]=38, that is, the contents of register 3 is the number 38, then this number will be put into register 5.  The contents of register 3 are not disturbed by this operation, so [3] continues to be 38, now the same as [5].

Definition: A direct instruction is one that specifies in the instruction itself the address of the source or destination register whose contents will be the subject of the instruction.
Definition: An indirect instruction is one that specifies a "pointer register", the contents of which is the address of a "target" register. The target register can be either a source or a destination (the various COPY instructions provide examples of this). A register can address itself indirectly.
For want of a standard/convention this article will specify "direct/indirect", abbreviated as "d/i", as a parameter (or parameters) in the instruction:
Example: COPY ( d, A, i, N ) means directly d get the source register's address (register "A") from the instruction itself but indirectly i get the destination address from pointer-register N. Suppose [N]=3, then register 3 is the destination and the instruction will do the following: [A] → 3.

Definition: The contents of source register is used by the instruction. The source register's address can be specified either (i) directly by the instruction, or (ii) indirectly by the pointer register specified by the instruction.

Definition: The contents of the pointer register is the address of the "target" register.

Definition: The contents of the pointer register points to the target registerthe "target" may be either a source or a destination register.

Definition: The destination register is where the instruction deposits its result. The source register's address can be specified either (i) directly by the instruction, or (ii) indirectly by the pointer register specified by the instruction. The source and destination registers can be one.

Refresher: The counter-machine model
Melzak (1961) provides an easy visualization of a counter machine: its "registers" are holes in the ground, and these holes hold pebbles. Per an instruction, into and out of these holes "the computer" (person or machine) adds (INCrements) or removes (DECrements) a single pebble. As needed, additional pebbles come from, and excess pebbles go back into, an infinite supply; if the hole is too small to accommodate the pebbles the "computer" digs the hole bigger.

Minsky (1961) and Hopcroft-Ullman 1979 (p. 171) offer the visualization of a multi-tape Turing machine with as many left-ended tapes as "registers". Each tape's length is unbounded to the right, and every square is blank except for the left end, which is marked. The distance of a tape's "head" from its left end, measured in numbers of tape-squares, represents the natural number in "the register". To DECrement the count of squares the tape head moves left; INCrement it moves right. There is no need to print or erase marks on the tape; the only conditional instructions are to check to see if the head is at the left end, by testing a left-end mark with a "Jump-if-marked instruction".

The following instruction "mnemonics" e.g. "CLR (r)" are arbitrary; no standard exists.

The register machine has, for a memory external to its finite-state machinean unbounded (cf: footnote|countable and unbounded) collection of discrete and uniquely labelled locations with unbounded capacity, called "registers". These registers hold only natural numbers (zero and positive integers). Per a list of sequential instructions in the finite state machine's TABLE, a few (e.g. 2) types of primitive operations operate on the contents of these "registers". Finally, a conditional-expression in the form of an IF-THEN-ELSE is available to test the contents of one or two registers and "branch/jump" the finite state machine out of the default instruction-sequence.

Base model 1: The model closest to Minsky's (1961) visualization and to Lambek (1961):
 { INCrement contents of register r, DECrement contents of register r, IF contents of register r is Zero THEN Jump to instruction Iz ELSE continue to next instruction }:

Base model 2: The "successor" model (named after the successor function of the Peano axioms):
 { INCrement the contents of register r, CLeaR the contents of register r, IF contents of register rj Equals the contents of register rk THEN Jump to instruction Iz ELSE goto to next instruction }

Base model 3: Used by Elgot-Robinson (1964) in their investigation of bounded and unbounded RASPsthe "successor" model with COPY in the place of CLEAR:
 { INCrement the contents of register r, COPY the contents of register rj to register rk, IF contents of register rj Equals the contents of register rk then Jump to instruction Iz ELSE goto to next instruction }

Creating "convenience instructions" from the base sets
The three base sets 1, 2, or 3 above are equivalent in the sense that one can create the instructions of one set using the instructions of another set (an interesting exercise: a hint from Minsky (1967)declare a reserved register e.g. call it "0" (or Z for "zero" or E for "erase") to contain the number 0). The choice of model will depend on which an author finds easiest to use in a demonstration, or a proof, etc.

Moreover, from base sets 1, 2, or 3 we can create any of the primitive recursive functions ( cf Minsky (1967), Boolos-Burgess-Jeffrey (2002) ). (How to cast the net wider to capture the total and partial mu recursive functions will be discussed in context of indirect addressing). However, building the primitive recursive functions is difficult because the instruction sets are so ... primitive (tiny). One solution is to expand a particular set with "convenience instructions" from another set:
These will not be subroutines in the conventional sense but rather blocks of instructions created from the base set and given a mnemonic. In a formal sense, to use these blocks we need to either (i) "expand" them into their base-instruction equivalentsthey will require the use of temporary or "auxiliary" registers so the model must take this into account, or (ii) design our machines/models with the instructions 'built in'.
Example: Base set 1. To create CLR (r) use the block of instructions to count down register r to zero. Observe the use of the hint mentioned above:
 CLR (r) =equiv
 loop: JZ (r, exit)
 DEC (r)
 JZ (0, loop)
 exit: etc.

Again, all of this is for convenience only; none of this increases the model's intrinsic power.

For example: the most expanded set would include each unique instruction from the three sets, plus unconditional jump J (z) i.e.:
 { CLR (r), DEC (r), INC (r), CPY ( rs, rd ), JZ (r, z), JE ( rj, rk, z ), J(z) }

Most authors pick one or the other of the conditional jumps, e.g. Shepherdson-Sturgis (1963) use the above set minus JE (to be perfectly accurate they use JNZJump if Not Zero in place of JZ; yet another possible convenience instruction).

The "indirect" operation

Example of indirect addressing
In our daily lives the notion of an "indirect operation" is not unusual.
Example: A treasure hunt.
At location "Tom_&_Becky's_cave_in_pirate_chest" will be where we can find a map directing us to "the treasure":
(1) We go to location "Tom_&_Becky's_cave..." and dig around until we find a wooden box
(2) Inside the box is a map to the location of the treasure: "under_Thatcher's_front_porch"
(3) We go to location "under_Thatcher's_front_porch", jackhammer away the concrete, and discover "the treasure": a sack of rusty door-knobs.

Indirection specifies a location identified as the pirate chest in "Tom_&_Becky's_cave..." that acts as a pointer to any other location (including itself): its contents (the treasure map) provides the "address" of the target location
"under_Thatcher's_front_porch" where the real action is occurring.

Why the need for an indirect operation: Two major problems with the counter-machine model
In the following one must remember that these models are abstract models with two fundamental differences from anything physically real: unbounded numbers of registers each with unbounded capacities. The problem appears most dramatically when one tries to use a counter-machine model to build a RASP that is Turing equivalent and thus compute any partial mu recursive function:
 Melzak (1961) added indirection to his "hole-and-pebble" model so that his model could modify itself with a "computed goto" and provides two examples of its use ("Decimal representation in the scale of d" and "Sorting by magnitude", whether these are used in his proof that the model is Turing equivalent is unclear since "the program itself is left to the reader as an exercise" (p. 292)). Minsky (1961, 1967) was able to demonstrate that, with suitable (but difficult-to-use) Gödel number encoding, the register model did not need indirection to be Turing equivalent; but it did need at least one unbounded register. As noted below, Minsky (1967) hints at the problem for a RASP but doesn't offer a solution. Elgot and Robinson (1964) proved that their RASP model P0it has no indirection capabilitycannot compute all "recursive sequential functions" (ones that have parameters of arbitrary length) if it does not have the capability of modifying its own instructions, but it can via Gödel numbers if it does (p. 395-397; in particular figure 2 and footnote p. 395). On the other hand their RASP model P'0 equipped with an "index register" (indirect addressing) can compute all the "partial recursive sequential functions" (the mu recursive functions) (p. 397-398).
Cook and Reckhow (1973) say it most succinctly:
The indirect instructions are necessary in order for a fixed program to access an unbounded number of registers as the inputs vary." (p. 73)
 Unbounded capacities of registers versus bounded capacities of state-machine instructions: The so-called finite state part of the machine is supposed to beby the normal definition of algorithmvery finite both in the number of "states" (instructions) and the instructions' sizes (their capacity to hold symbols/signs). So how does a state machine move an arbitrarily large constant directly into a register, e.g. MOVE (k, r) (Move constant k to register r)? If huge constants are necessary they must either start out in the registers themselves or be created by the state machine using a finite number of instructions e.g. multiply  and add subroutines using INC and DEC (but not a quasi-infinite number of these!).
Sometimes the constant k will be created by use of CLR ( r ) followed by INC ( r ) repeated k timese.g. to put the constant k=3 into register r, i.e. 3 → r, so at the end of the instruction [r]=3: CLR (r), INC (r), INC (r), INC (r). This trick is mentioned by Kleene (1952) p. 223. The problem arises when the number to be created exhausts the number of instructions available to the finite state machine; there is always a bigger constant than the number of instructions available to the finite state machine.
 Unbounded numbers of registers versus bounded state-machine instructions: This is more severe than the first problem. In particular, this problem arises when we attempt to build a so-called RASP, a "universal machine" (see more at Universal Turing machine) that uses its finite-state machine to interpret a "program of instructions" located in its registersi.e. we are building what is nowadays called a computer with the von Neumann architecture.

Observe that the counter machine's finite state machine must call out a register explicitly (directly) by its name/number: INC (65,356) calls out register number "65,365" explicitly. If the number of registers exceeds the capability of the finite state machine to address them, then registers outside the bounds will be unreachable. For example, if the finite state machine can only reach 65,536 = 216 registers then how can it reach the 65,537th?

So how do we address a register beyond the bounds of the finite state machine? One approach would be to modify the program-instructions (the ones stored in the registers) so that they contain more than one command. But this too can be exhausted unless an instruction is of (potentially) unbounded size. So why not use just one "über-instruction"one really really big numberthat contains all the program instructions encoded into it! This is how Minsky solves the problem, but the Gödel numbering he uses represents a great inconvenience to the model, and the result is nothing at all like our intuitive notion of a "stored program computer".

Elgot and Robinson (1964) come to a similar conclusion with respect to a RASP that is "finitely determined". Indeed it can access an unbounded number of registers (e.g. to fetch instructions from them) but only if the RASP allows "self modification" of its program instructions, and has encoded its "data" in a Gödel number (Fig. 2 p. 396).

In the context of a more computer-like model using his RPT (repeat) instruction Minsky (1967) tantalizes us with a solution to the problem (cf p. 214, p. 259) but offers no firm resolution. He asserts:
"In general a RPT operation could not be an instruction in the finite-state part of the machine ... this might exhaust any particular amount of storage allowed in the finite part of the computer [sic, his name for his RAM models]. RPT operations require infinite registers of their own." (p. 214).

He offers us a bounded RPT that together with CLR (r) and INC (r) can compute any primitive recursive function, and he offers the unbounded RPT quoted above that as playing the role of μ operator; it together with CLR (r) and INC (r) can compute the mu recursive functions. But he does not discuss "indirection" or the RAM model per se.

From the references in Hartmanis (1971) it appears that Cook (in his lecture notes while at UC Berkeley, 1970) has firmed up the notion of indirect addressing. This becomes clearer in the paper of Cook and Reckhow (1973)Cook is Reckhow's Master's thesis advisor. Hartmanis' modelquite similar to Melzak's (1961) modeluses two and three-register adds and subtracts and two parameter copies; Cook and Reckhow's model reduce the number of parameters (registers called out in the program instructions) to one call-out by use of an accumulator "AC".

The solution in a nutshell: Design our machine/model with unbounded indirectionprovide an unbounded "address" register that can potentially name (call out) any register no matter how many there are. For this to work, in general, the unbounded register requires an ability to be cleared and then incremented (and, possibly, decremented) by a potentially infinite loop. In this sense the solution represents the unbounded μ operator that can, if necessary, hunt ad infinitum along the unbounded string of registers until it finds what it is looking for. The pointer register is exactly like any other register with one exception: under the circumstances called "indirect addressing" it provides its contents, rather than the address-operand in the state machine's TABLE, to be the address of the target register (including possibly itself!).

Bounded indirection and the primitive recursive functions
If we eschew the Minsky approach of one monster number in one register, and specify that our machine model will be "like a computer" we have to confront this problem of indirection if we are to compute the recursive functions (also called the μ-recursive functions )both total and partial varieties.

Our simpler counter-machine model can do a "bounded" form of indirectionand thereby compute the sub-class of primitive recursive functionsby using a primitive recursive "operator" called "definition by cases" (defined in Kleene (1952) p. 229 and Boolos-Burgess-Jeffrey p. 74). Such a "bounded indirection" is a laborious, tedious affair. "Definition by cases" requires the machine to determine/distinguish the contents of the pointer register by attempting, time after time until success, to match this contents against a number/name that the case operator explicitly declares. Thus the definition by cases starts from e.g. the lower bound address and continues ad nauseam toward the upper bound address attempting to make a match:
 Is the number in register N equal to 0? If not then is it equal to 1? 2? 3? ... 65364? If not then we're at the last number 65365 and this had better be the one, else we have a problem!

"Bounded" indirection will not allow us to compute the partial recursive functionsfor those we need unbounded indirection aka the μ operator.
Suppose we had been able to continue on to number 65367, and in fact that register had what we were looking for. Then we could have completed our calculation successfully! But suppose 65367 didn't have what we needed. How far should we continue to go?

To be Turing equivalent the counter machine needs to either use the unfortunate single-register Minsky Gödel number method, or be augmented with an ability to explore the ends of its register string, ad infinitum if necessary. (A failure to find something "out there" defines what it means for an algorithm to fail to terminate; cf Kleene (1952) pp. 316ff Chapter XII Partial Recursive Functions, in particular p. 323-325.) See more on this in the example below.

Unbounded indirection and the partial recursive functions
For unbounded indirection we require a "hardware" change in our machine model. Once we make this change the model is no longer a counter machine, but rather a random-access machine.

Now when e.g. INC  is specified, the finite state machine's instruction will have to specify where the address of the register of interest will come from. This where can be either (i) the state machine's instruction that provides an explicit label, or (ii) the pointer-register whose contents is the address of interest. Whenever an instruction specifies a register address it now will also need to specify an additional parameter "i/d""indirect/direct". In a sense this new "i/d" parameter is a "switch" that flips one way to get the direct address as specified in the instruction or the other way to get the indirect address from the pointer register (which pointer registerin some models every register can be a pointer registeris specified by the instruction). This "mutually exclusive but exhaustive choice" is yet another example of "definition by cases", and the arithmetic equivalent shown in the example below is derived from the definition in Kleene (1952) p. 229.

Example: CPY ( indirectsource, rsource, directdestination, rdestination )

Assign a code to specify direct addressing as d="0" and indirect addressing as i="1". Then our machine can determine the source address as follows:
 i*[rs] + (1-i)*rs
For example, suppose the contents of register 3 are "5" (i.e. [3]=5 ) and the contents of register 4 are "2" (i.e. [4]=2 ):

 Example: CPY ( 1, 3, 0, 4 ) = CPY ( indirect, reg 3, direct, reg 4 )
 1*[3] + 0*3 = [3] = source-register address 5
 0*[4] + 1*4 = 4 = destination-register address 4

 Example: CPY ( 0, 3, 0, 4 )
 0*[3] + 1*3 = 3 = source-register address 3
 0*[4] + 1*4 = 4 = destination-register address 4

 Example: CPY ( 0, 3, 1, 4 )
 0*[3] + 1*3 = 3 = source-register address 3
 1*[4] + 0*4 = [4] = destination-register address 2

The indirect COPY instruction
Probably the most useful of the added instructions is COPY. Indeed, Elgot-Robinson (1964) provide their models P0 and P'0 with the COPY instructions, and Cook-Reckhow (1973) provide their accumulator-based model with only two indirect instructionsCOPY to accumulator indirectly, COPY from accumulator indirectly.

A plethora of instructions: Because any instruction acting on a single register can be augmented with its indirect "dual" (including conditional and unconditional jumps, cf the Elgot-Robinson model), the inclusion of indirect instructions will double the number of single parameter/register instructions (e.g. INC (d, r), INC (i, r)). Worse, every two parameter/register instruction will have 4 possible varieties, e.g.:

 CPY (d, rs, d, rd ) = COPY directly from source-register directly to destination-register
 CPY (i, rsp, d, rd ) = COPY to destination-register indirectly using the source address to be found in the source-pointer register rsp.
 CPY (d, rs, i, rdp ) = COPY contents of source-register indirectly into register using destination address to be found in the destination-pointer register rdp.
 CPY (i, rsp, i, rdp ) = COPY indirectly the contents of the source register with address to be found in source-pointer register rsp, into the destination register with address to be found in the destination-pointer register rdp)

In a similar manner every three-register instruction that involves two source registers rs1 rs2 and a destination register rd will result in 8 varieties, for example the addition:
 [rs1] + [rs2] → rd

will yield:
 ADD ( d, rs1, d, rs2, d, rd )
 ADD ( i, rsp1, d, rs2, d, rd )
 ADD ( d, rs1, i, rsp2, d, rd )
 ADD ( i, rsp1, i, rsp2, d, rd )
 ADD ( d, rs1, d, rs2, i, rdp )
 ADD ( i, rsp1, d, rs2, i, rdp )
 ADD ( d, rs1, i, rsp2, i, rdp )
 ADD ( i, rsp1, i, rsp2, i, rdp )

If we designate one register to be the "accumulator" (see below) and place strong restrictions on the various instructions allowed then we can greatly reduce the plethora of direct and indirect operations. However, one must be sure that the resulting reduced instruction-set is sufficient, and we must be aware that the reduction will come at the expense of more instructions per "significant" operation.

The notion of "accumulator A"
Historical convention dedicates a register to the accumulator,  an "arithmetic organ" that literally accumulates its number during a sequence of arithmetic operations:
"The first part of our arithmetic organ ... should be a parallel storage organ which can receive a number and add it to the one already in it, which is also able to clear its contents and which can store what it contains. We will call such an organ an Accumulator. It is quite conventional in principle in past and present computing machines of the most varied types, e.g. desk multipliers, standard IBM counters, more modern relay machines, the ENIAC" (boldface in original: Goldstine and von Neumann, 1946; p. 98 in Bell and Newell 1971).

However, the accumulator comes at the expense of more instructions per arithmetic "operation", in particular with respect to what are called 'read-modify-write' instructions such as "Increment indirectly the contents of the register pointed to by register r2 ". "A" designates the "accumulator" register A:

If we stick with a specific name for the accumulator, e.g. "A", we can imply the accumulator in the instructions, for example,
 INC ( A ) = INCA
However, when we write the CPY instructions without the accumulator called out the instructions are ambiguous or they must have empty parameters:
 CPY ( d, r2, d, A ) = CPY (d, r2, , )
 CPY ( d, A, d, r2 ) = CPY ( , , d, r2)

Historically what has happened is these two CPY instructions have received distinctive names; however, no convention exists. Tradition (e.g. Knuth's (1973) imaginary MIX computer) uses two names called LOAD and STORE. Here we are adding the "i/d" parameter:
 LDA ( d/i, rs ) =def  CPY ( d/i, rs, d, A )
 STA ( d/i, rd ) =def  CPY ( d, A, d/i, rd )

The typical accumulator-based model will have all its two-variable arithmetic and constant operations (e.g. ADD (A, r), SUB (A, r) ) use (i) the accumulator's contents, together with (ii) a specified register's contents.  The one-variable operations (e.g. INC (A), DEC (A) and CLR (A) ) require only the accumulator. Both instruction-types deposit the result (e.g. sum, difference, product, quotient or remainder) in the accumulator.
 Example: INCA = [A] +1 → A
 Example: ADDA (rs) = [A] + [rs] → A
 Example: MULA (rs) = [A] * [rs] → A

If we so choose, we can abbreviate the mnemonics because at least one source-register and the destination register is always the accumulator A. Thus we have :
{ LDA (i/d, rs), STA (i/d, rd), CLRA, INCA, DECA, ADDA (rs), SUBA (rs), MULA (rs), DIVA (rs), etc.)

The notion of indirect address register "N"
If our model has an unbounded accumulator can we bound all the other registers? Not until we provide for at least one unbounded register from which we derive our indirect addresses.

The minimalist approach is to use itself (Schönhage does this).

Another approach (Schönhage does this too) is to declare a specific register the "indirect address register" and confine indirection relative to this register (Schonhage's RAM0 model uses both A and N registers for indirect as well as direct instructions). Again our new register has no conventional nameperhaps "N" from "iNdex", or "iNdirect" or "address Number".

For maximum flexibility, as we have done for the accumulator Awe will consider N just another register subject to increment, decrement, clear, test, direct copy, etc. Again we can shrink the instruction to a single-parameter that provides for direction and indirection, for example.
 LDAN (i/d) = CPY (i/d, N, d, A); LoaD Accumulator via iNdirection register
 STAN (i/d) = CPY (d, A, i/d, N). STore Accumulator via iNdirection register

Why is this such an interesting approach? At least two reasons:

(1) An instruction set with no parameters:

Schönhage does this to produce his RAM0 instruction set. See section below.

(2) Reduce a RAM to a Post-Turing machine:

Posing as minimalists, we reduce all the registers excepting the accumulator A and indirection register N e.g. r = { r0, r1, r2, ... } to an unbounded string of (very-) bounded-capacity pigeon-holes. These will do nothing but hold (very-) bounded numbers e.g. a lone bit with value { 0, 1 }. Likewise we shrink the accumulator to a single bit. We restrict any arithmetic to the registers { A, N }, use indirect operations to pull the contents of registers into the accumulator and write 0 or 1 from the accumulator to a register:
{ LDA (i, N), STA (i, N), CLR (A/N), INC (A/N), DEC(N), JZ (A/N, Iz), JZ (Iz), H }

We push further and eliminate A altogether by the use of two "constant" registers called "ERASE" and "PRINT": [ERASE]=0, [PRINT]=1.
{ CPY (d, ERASE, i, N), CPY (d, PRINT, i, N), CLR (N), INC (N), DEC (N), JZ (i, N, Iz), JZ (Iz), H }

Rename the COPY instructions and call INC (N) = RIGHT, DEC (N) = LEFT and we have the same instructions as the Post-Turing machine, plus an extra CLRN :
{ ERASE, PRINT, CLRN, RIGHT, LEFT, JZ (i, N, Iz), JZ (Iz), H }

Turing equivalence of the RAM with indirection
In the section above we informally showed that a RAM with an unbounded indirection capability produces a Post–Turing machine. The Post–Turing machine is Turing equivalent, so we have shown that the RAM with indirection is Turing equivalent.

We give here a slightly more formal demonstration. Begin by designing our model with three reserved registers "E", "P", and "N", plus an unbounded set of registers 1, 2, ..., n to the right. The registers 1, 2, ..., n will be considered "the squares of the tape". Register "N" points to "the scanned square" that "the head" is currently observing. The "head" can be thought of as being in the conditional jumpobserve that it uses indirect addressing (cf Elgot-Robinson p. 398). As we decrement or increment "N" the (apparent) head will "move left" or "right" along the squares. We will move the contents of "E"=0 or "P"=1 to the "scanned square" as pointed to by N, using the indirect CPY.

The fact that our tape is left-ended presents us with a minor problem: Whenever LEFT occurs our instructions will have to test to determine whether or not the contents of "N" is zero; if so we should leave its count at "0" (this is our choice as designersfor example we might have the machine/model "trigger an event" of our choosing).

Instruction set 1 (augmented): { INC (N), DEC (N), CLR (N), CPY (d, rs,i, N), JZ ( i, r, z ), HALT }

The following table both defines the Post-Turing instructions in terms of their RAM equivalent instructions and gives an example of their functioning. The (apparent)location of the head along the tape of registers r0-r5 . . . is shown shaded:

Example: Bounded indirection yields a machine that is not Turing equivalent
Throughout this demonstration we have to keep in mind that the instructions in the finite state machine's TABLE is bounded, i.e. finite:
"Besides a merely being a finite set of rules which gives a sequence of operations for solving a specific type of problem, an algorithm has five important features [Finiteness, Definiteness, Input, Output, Effectiveness]" (italics added, Knuth p. 4-7).

The difficulty arises because the registers have explicit "names" (numbers) and our machine must call each out by name in order to "access" it.

We will build the indirect CPY ( i, q, d, φ ) with the CASE operator. The address of the target register will be specified by the contents of register "q"; once the CASE operator has determined what this number is, CPY will directly deposit the contents of the register with that number into register "φ". We will need an additional register that we will call "y"it serves as an up-counter.

So the following is actually a constructive demonstration or proof that we can indeed simulate the indirect CPY ( i, q, d, φ ) without a "hardware" design change to our counter machine/model. However, note that because this indirect CPY is "bounded" by the size/extent of the finite state machine, a RASP using this indirect CPY can only calculate the primitive recursive functions, not the full suite of mu recursive functions.

The CASE "operator" is described in Kleene (1952) (p. 229) and in Boolos-Burgess-Jeffrey (2002) (p. 74); the latter authors emphasize its utility. The following definition is per Kleene but modified to reflect the familiar "IF-THEN-ELSE" construction.

The CASE operator "returns" a natural number into φ depending on which "case" is satisfied, starting with "case_0" and going successively through "case_last"; if no case is satisfied then the number called "default" (aka "woops") is returned into φ (here x designates some selection of parameters, e.g. register q and the string r0, ... rlast )):

Definition by cases φ (x, y):
 case_0: IF Q0(x, y) is true THEN φ0(x, y) ELSE
 case_1: IF Q1(x, y) is true THEN φ1(x, y) ELSE
 cases_2 through case_next_to_last: etc. . . . . . . . . ELSE
 case_last: IF Qlast(x, y) is true THEN φlast(x, y) ELSE
 default: do φdefault(x, y)

Kleene require that the "predicates" Qn that doing the testing are all mutually exclusive"predicates" are functions that produce only { true, false } for output; Boolos-Burgess-Jeffrey add the requirement that the cases are "exhaustive".

We begin with a number in register q that represents the address of the target register. But what is this number? The "predicates" will test it to find out, one trial after another: JE (q, y, z) followed by INC (y). Once the number is identified explicitly, the CASE operator directly/explicitly copies the contents of this register to φ:

Definition by cases CPY (i, q, d, φ) =def φ (q, r0, ..., rlast, y) =
 case_0: IF CLR (y), [q] - [y]=0  THEN CPY ( r0, φ ), J (exit) ELSE
 case_1: IF  INC (y), [q] = [y]=1 THEN CPY ( r1, φ ), J (exit) ELSE
 case_2 through case n: IF . . . THEN . . . ELSE
 case_n: IF  INC (y), [q] = [y]=n THEN CPY ( rn, φ ), J (exit) ELSE
 case_n+1 to case_last: IF . . . THEN . . . ELSE
 case_last: IF INC (y), [q] = [y]="last" THEN CPY ( rlast, φ ), J (exit) ELSE
 default: woops

Case_0 ( the base step of the recursion on y) looks like this:
 case_0:
 CLR ( y ) ; set register y = 0
 JE ( q, y, _φ0 )
 J ( case_1 )
 _φ0: CPY ( r0, φ )
 J ( exit )
 case_1: etc.

Case_n (the induction step) looks like this; remember, each instance of "n", "n+1", ..., "last" must be an explicit natural number:
 case_n:
 INC ( y )
 JE ( q, y, _φn )
 J ( case_n+1)
 _φn: CPY ( rn, φ )
 J ( exit )
case__n+1: etc.

Case_last stops the induction and bounds the CASE operator (and thereby bounds the "indirect copy" operator):
 case_last:
 INC ( y )
 JE ( q, y, _φlast )
 J ( woops )
 _φlast: CPY ( rlast, φ )
 J ( exit )
woops: how do we handle an out-of-bounds attempt?
exit: etc.

If the CASE could continue ad infinitum it would be the mu operator. But it can'tits finite state machine's "state register" has reached its maximum count (e.g. 65365 = 11111111,111111112 ) or its table has run out of instructions; it is a finite machine, after all.

Examples of models

Register-to-register ("read-modify-write") model of Cook and Reckhow (1973)
The commonly encountered Cook and Rechkow model is a bit like the ternary-register Malzek model (written with Knuth mnemonicsthe original instructions had no mnemonics excepting TRA, Read, Print).

 LOAD ( C, rd ) ; C → rd, C is any integer
 Example: LOAD ( 0, 5 ) will clear register 5.
 ADD ( rs1, rs2, rd  ) ; [rs1] + [rs2] → rd, the registers can be the same or different;
Example: ADD ( A, A, A ) will double the contents of register A.
 SUB ( rs1, rs2, rd ) ; [rs1] - [rs2] → rd, the registers can be the same or different:
Example: SUB ( 3, 3, 3 ) will clear register 3.
 COPY ( i, rp, d, rd ) ; [[rp] ] →  rd, Indirectly copy the contents of the source-register pointed to by pointer-register rp into the destination register.
 COPY ( d, rs, i, rp ) ; [rs] → [rp]. Copy the contents of source register rs into the destination-register pointed to by the pointer-register rp.
 JNZ ( r, Iz ) ; Conditional jump if [r] is positive; i.e. IF [r] > 0 THEN jump to instruction z else continue in sequence (Cook and Reckhow call this: "TRAnsfer control to line m if Xj > 0")
 READ ( rd ) ; copy "the input" into destination register rd
 PRINT ( rs ) ; copy the contents of source register rs to "the output."

Schönhage's RAM0 and RAM1 (1980)
Schönhage (1980) describes a very primitive, atomized model chosen for his proof of the equivalence of his SMM pointer machine model:
"In order to avoid any explicit addressing the RAM0 has the accumulator with contents z and an additional address register with current contents n (initially 0)" (p. 494)

RAM1 model: Schönhage demonstrates how his construction can be used to form the more common, usable form of "successor"-like RAM (using this article's mnemonics):
 LDA k ; k --> A , k is a constant, an explicit number such as "47"
 LDA ( d, r ) ; [r] → A ; directly load A
 LDA ( i, r ) ; [[r]] → A ; indirectly load A
 STA ( d, r ) ; [A] → r ; directly store A
 STA ( i, r ) ; [A] → [r] ; indirectly store A
 JEA ( r, z ) ; IF [A] = [r] then Iz else continue
 INCA ; [A] + 1 --> A

RAM0 model: Schönhage's RAM0 machine has 6 instructions indicated by a single letter (the 6th "C xxx" seems to involve 'skip over next parameter'. Schönhage designated the accumulator with "z", "N" with "n", etc. Rather than Schönhage's mnemonics we will use the mnemonics developed above.
(Z), CLRA:  0 → A
(A), INCA:  [A] +1 → A
(N), CPYAN:  [A] → N
(A), LDAA: [[A]] → A ; contents of A points to register address; put register's contents into A
(S), STAN: [A] → [N] ; contents of N points to register address; put contents of A into register pointed to by N
(C), JAZ ( z ): [A] = 0 then go to Iz ; ambiguous in his treatment

Indirection comes (i) from CPYAN (copy/transfer contents A to N) working with store_A_via_N STAN, and from (ii) the peculiar indirection instruction LDAA ( [[A]] → [A] ).

Footnotes

Finite vs unbounded
The definitional fact that any sort of counter machine without an unbounded register-"address" register must specify a register "r" by name indicates that the model requires "r" to be finite, although it is "unbounded" in the sense that the model implies no upper limit to the number of registers necessary to do its job(s). For example, we do not require r < 83,617,563,821,029,283,746 nor r < 2^1,000,001, etc.

Thus our model can "expand" the number of registers, if necessary to perform a certain computation. However this does mean that whatever number the model expands to must be finiteit must be indexable with a natural number: ω is not an option.

We can escape this restriction by providing an unbounded register to provide the address of the register that specifies an indirect address.

See also
 Real RAM
 Transdichotomous model

External links
 Random Access Machine Emulator
 Random Access Machine Emulator
 Random Access Machine Emulator

References
With a few exceptions, these references are the same as those at Register machine.
 Goldstine, Herman H., and von Neumann, John, "Planning and Coding of the Problems for an Electronic Computing Instrument", Rep. 1947, Institute for Advanced Study, Princeton. Reprinted on pp. 92–119 in Bell, C. Gordon and Newell, Allen (1971), Computer Structures: Readings and Examples, McGraw-Hill Book Company, New York. }.
 George Boolos, John P. Burgess, Richard Jeffrey (2002), Computability and Logic: Fourth Edition, Cambridge University Press, Cambridge, England. The original Boolos-Jeffrey text has been extensively revised by Burgess: more advanced than an introductory textbook. "Abacus machine" model is extensively developed in Chapter 5 Abacus Computability; it is one of three models extensively treated and comparedthe Turing machine (still in Boolos' original 4-tuple form) and recursion the other two.
 Arthur Burks, Herman Goldstine, John von Neumann (1946), Preliminary discussion of the logical design of an electronic computing instrument, reprinted pp. 92ff in Gordon Bell and Allen Newell (1971), Computer Structures: Readings and Examples, mcGraw-Hill Book Company, New York.   .
 Stephen A. Cook and Robert A. Reckhow (1973), Time-bounded random access machines, Journal of Computer Systems Science 7(4):354-375.
 Martin Davis (1958), Computability & Unsolvability, McGraw-Hill Book Company, Inc. New York.
 Calvin Elgot and Abraham Robinson (1964), Random-Access Stored-Program Machines, an Approach to Programming Languages, Journal of the Association for Computing Machinery, Vol. 11, No. 4 (October, 1964), pp. 365–399.
 J. Hartmanis (1971), "Computational Complexity of Random Access Stored Program Machines," Mathematical Systems Theory 5, 3 (1971) pp. 232–245.
 John Hopcroft, Jeffrey Ullman (1979). Introduction to Automata Theory, Languages and Computation, 1st ed., Reading Mass: Addison-Wesley. .  A difficult book centered around the issues of machine-interpretation of "languages", NP-Completeness, etc.
 Stephen Kleene (1952), Introduction to Metamathematics, North-Holland Publishing Company, Amsterdam, Netherlands. .
 Donald Knuth (1968), The Art of Computer Programming, Second Edition 1973, Addison-Wesley, Reading, Massachusetts. Cf pages 462-463 where he defines "a new kind of abstract machine or 'automaton' which deals with linked structures."
 Joachim Lambek (1961, received 15 June 1961), How to Program an Infinite Abacus, Mathematical Bulletin, vol. 4, no. 3. September 1961 pages 295-302. In his Appendix II, Lambek proposes a "formal definition of 'program'. He references Melzak (1961) and Kleene (1952) Introduction to Metamathematics.
 Z. A. Melzak (1961, received 15 May 1961), An informal Arithmetical Approach to Computability and Computation, Canadian Mathematical Bulletin, vol. 4, no. 3. September 1961 pages 279-293. Melzak offers no references but acknowledges "the benefit of conversations with Drs. R. Hamming, D. McIlroy and V. Vyssots of the Bell telephone Laborators and with Dr. H. Wang of Oxford University."

  In particular see chapter 11: Models Similar to Digital Computers and chapter 14: Very Simple Bases for Computability. In the former chapter he defines "Program machines" and in the later chapter he discusses "Universal Program machines with Two Registers" and "...with one register", etc.
 John C. Shepherdson and H. E. Sturgis (1961) received December 1961 Computability of Recursive Functions, Journal of the Association for Computing Machinery (JACM) 10:217-255, 1963. An extremely valuable reference paper. In their Appendix A the authors cite 4 others with reference to "Minimality of Instructions Used in 4.1: Comparison with Similar Systems".
Kaphengst, Heinz, Eine Abstrakte programmgesteuerte Rechenmaschine''', Zeitschrift fur mathematische Logik und Grundlagen der Mathematik:5 (1959), 366-379.
Ershov, A. P. On operator algorithms, (Russian) Dok. Akad. Nauk 122 (1958), 967-970. English translation, Automat. Express 1 (1959), 20-23.
Péter, Rózsa Graphschemata und rekursive Funktionen, Dialectica 12 (1958), 373.
Hermes, Hans Die Universalität programmgesteuerter Rechenmaschinen. Math.-Phys. Semsterberichte (Göttingen) 4 (1954), 42-53.
 Arnold Schönhage (1980), Storage Modification Machines, Society for Industrial and Applied Mathematics, SIAM J. Comput. Vol. 9, No. 3, August 1980. Wherein Schōnhage shows the equivalence of his SMM with the "successor RAM" (Random Access Machine), etc. resp. Storage Modification Machines, in Theoretical Computer Science (1979), pp. 36–37
 Peter van Emde Boas, "Machine Models and Simulations" pp. 3–66, in: Jan van Leeuwen, ed. Handbook of Theoretical Computer Science. Volume A: Algorithms and Complexity, The MIT PRESS/Elsevier, 1990.  (volume A). QA 76.H279 1990. van Emde Boas's treatment of SMMs appears on pp. 32–35. This treatment clarifies Schōnhage 1980it closely follows but expands slightly the Schōnhage treatment. Both references may be needed for effective understanding.
 Hao Wang (1957), A Variant to Turing's Theory of Computing Machines'', JACM (Journal of the Association for Computing Machinery) 4; 63-92. Presented at the meeting of the Association, June 23–25, 1954.

Register machines

Random-access machine


Alexandre de Svir, appelé aussi Alexandre Svirsky, (1448-1533) est un saint du christianisme orthodoxe, un moine et un higoumène de l'Église orthodoxe russe.

Amos (nom donné à sa naissance) est né dans une famille paysanne de la République de Novgorod, à l'est du Lac Ladoga. À l'âge de 19 ans, il quitte la maison pour aller rejoindre le monastère de Valaam. Il devient moine et s'isole de façon occasionnelle. En 1506, Sérapion de Novgorod, archevêque de Novgorod, le nomme higoumène du monastère de la Trinité. Ce monastère porta plus tard le nom de Monastère Saint-Alexandre-de-Svir.

Saint Alexandre est reconnu pour sa vie juste et ses miracles contemplatifs, y compris les apparitions de la Trinité et de la Vierge Marie avec l'Enfant Jésus. L'Église orthodoxe russe canonise Alexandre de Svir en 1547. Il est commémoré le 17 avril et le 30 août selon le calendrier liturgique orthodoxe.

Des reliques de saint Alexandre ont été trouvées le 17 (27) avril 1641. Selon la Vita du saint, elles ont été trouvées incorruptibles .

Le 22 octobre 1918, le cercueil d'Alexandre de Svir a été ouvert. Selon les rapports soviétiques, au lieu d'y trouver des reliques, une poupée de cire reposait à l'intérieur du cercueil. Selon le témoignage des moines présents, ainsi qu'une commission soviétique ultérieure sous la direction de Grigory Zinoviev, un corps humain se trouvait dans le cercueil et non pas une figure de cire.

Références

Liens externes

Moine russe
Décès en 1533
Naissance en 1448
Article dont une information diffère dans l'infobox

Alexandre Svirski


L'efficacité politique, en science politique, est la confiance des citoyens dans leur capacité à changer le gouvernement et la conviction qu'ils peuvent comprendre et influencer les affaires politiques. Il est généralement mesuré par des enquêtes et est utilisé comme indicateur de la santé générale de la société civile.

Description du concept
L'efficacité politique des citoyens peut s'exprimer de multiples façons : à travers les médias, en ayant le droit de manifester, en pouvant créer des pétitions et en organisant des élections libres et équitables. Leur absence se traduit généralement par la violence et est un effet secondaire d'une faible efficacité politique, et donc du sentiment qu'un citoyen est impuissant dans son propre pays.

Le sentiment d'efficacité est fortement corrélé à la participation à la vie sociale et politique ; cependant, les études n'ont montré aucune relation entre la confiance du public dans le gouvernement ou les dirigeants politiques et le vote. Il a été constaté que l'efficacité politique polarisait les préférences politiques. Il a été constaté que les personnes ayant une efficacité relativement élevée expriment des préférences politiques plus conformes à leur orientation idéologique et plus extrêmes ; et les personnes peu efficaces ont tendance à exprimer des préférences politiques plus modérées. Ces résultats proviennent à la fois d'études expérimentales et d'études observationnelles.

Il existe deux types d'efficacité politique : l'efficacité interne (la conviction que l'on peut comprendre la politique et donc participer à la politique) et l'efficacité externe (que le gouvernement répondra à ses demandes).

Voir aussi
 Aliénation politique

Références

Lexique politique

Efficacité politique


Garfield "Gar" Heard (nacido el  en Hogansville, Georgia) es un exjugador y exentrenador de baloncesto estadounidense que disputó once temporadas en la NBA, y fue entrenador en la misma competición durante dos temporadas más. Con 1,98 metros de estatura, jugaba en la posición de alero.

Trayectoria deportiva

Universidad
Jugó durante 4 temporadas con los Sooners de la Universidad de Oklahoma, en las que promedió 15,7 puntos y 10,6 rebotes por partido. En su última temporada consiguió el récord de su universidad de más doble-dobles, con 21, que fue batido casi 40 años más tarde por Blake Griffin. Ese año fue elegido mejor jugador de la Big-8 Conference.

Profesional
Fue elegido en la cuadragésima posición del Draft de la NBA de 1970 por Seattle SuperSonics, y también por los Memphis Pros en el draft de la ABA, fichando por los primeros. Allí jugó dos temporadas como suplente, siendo la mejor de ellas la segunda, en la que promedió 7,9 puntos y 7,6 rebotes por partido.

En  fue traspasado a Chicago Bulls a cambio de Kennedy McIntosh. Su única temporada en el equipo se saldó con 10,3 puntos y 5,7 rebotes por partido, siendo traspasado al término de la misma a Buffalo Braves, junto con los derechos sobre Kevin Kunnert, a cambio de John Hummer y una futura segunda ronda del draft.

En los Braves consiguió la titularidad, siendo uno de los jugadores más destacados del equipo en su primera temporada, promediando 15,3 puntos, 11,7 rebotes y 2,8 tapones por partido, apareciendo entre los 10 mejores de la liga en estos dos últimos apartados.

Tras una temporada y media más en el equipo jugando a un buen nivel, en  fue traspasado a Phoenix Suns a cambio de John Shumate. Y fue en ese equipo donde protagonizó su jugada más recordada. Los Suns llegaron a las Finales esa temporada, donde se encontraron a los Boston Celtics. La eliminatoria se encontraba empatada a dos cuando se llegó al quinto partido, que acabó en el tiempo reglamentario en empate. Tras jugarse una primera prórroga con idéntico resultado, la controversia llegó en el segundo tiempo extra. A falta de 15 segundos para el final, los Celtics ganaban por 3 puntos, con el balón en posesión de los Suns. La línea de 3 puntos no se había instaurado todavía en la NBA. Dick Van Arsdale recibió el balón, se deshizo de su defensor y anotó de media distancia, poniendo a su equipo a un punto. Tras el saque de fondo, Paul Westphal robó el balón, pasándoselo a Curtis Perry, quien lanzó a canasta y falló, pero recuperó su propio rebote, anotando en su segundo esfuerzo para poner a los Suns un punto arriba, 110-109. Con cuatro segundos por jugar, los de Boston sacaron de medio campo tras un tiempo muerto, recibiendo la pelota John Havlicek, quien se lanzó hacia la canasta anotando. La locura se desató en el Boston Garden, con el público invadiendo el parquet, pero el árbitro de fondo no dejaba de señalar que el reloj no se había detenido al anotar, y que quedaba un segundo por jugar. Durante el alboroto, un fan de los Suns agredió a uno de los árbitros, siendo posteriormente detenido.

MacLeod, el entrenador de Phoenix, sabía que con un segundo por jugar y sacando desde debajo de su propia canasta, las posibilidades de ganar eran escasas, por lo que se le ocurrió el pedir un tiempo muerto del que no disponía, forzando la falta técnica que suponía un tiro libre para el rival, pero lo más importante: el balón se pondría en juego por parte de los Suns desde medio campo. White anotó el tiro libre, poniendo a los Celtics 2 arriba, pero en la jugada siguiente, con un segundo por jugar, Curtis Perry pasó a Heard, quien se giró y anotó desde 6 metros sobre la bocina, empatando el partido y llevándolo a una tercera prórroga. Finalmente no serviría de nada, ya que los Celtics ganaron el partido 128-126.

Heard jugó cuatro temporadas más con los Suns, perdiendo protagonismo paulatinamente. En  se convierte en agente libre, fichando por los San Diego Clippers. Allí jugaría su última temporada, en la que promedió 4,8 puntos y 4,5 rebotes por partido, antes de retirarse definitivamente.

Entrenador
Comenzó su carrera de entrenador como asistente en la Universidad Estatal de Arizona en 1982, para fichar en  como asistente de John MacLeod en Dallas Mavericks, quien ya había sido su entrenador en la universidad y en los Suns. En , tras la destitución de Richie Adubato, que había comenzado la liga con 2 victorias y 27 derrotas, asume el papel de entrenador principal interino de los Mavs, aunque su balance no fue mucho mejor, con 9 victorias y 44 derrotas.

En  ejerce de nuevo como asistente de Larry Brown en Indiana Pacers, donde permanece 4 temporadas, marchándose de nuevo a la sombra de Brown en  en Philadelphia 76ers. Al año siguiente se marcha a los Detroit Pistons, y en la temporada 1999-00 es contratado como entrenador principal de los Washington Wizards, donde reemplazó a Bernie Bickerstaff que había sido destituido en el mes de abril, y siendo elegido por encima de nombres como Isiah Thomas, Kareem Abdul-Jabbar o Glenn "Doc" Rivers que habían sonado para el puesto. Pero es destituido después de 44 partidos en los que sólo logra 14 victorias.

Posteriormente pasaría dos temporadas como asistente en los Atlanta Hawks y una más en Detroit Pistons, antes de retirarse.

Estadísticas de su carrera en la NBA

Temporada regular

Playoffs

Referencias

Enlaces externos

 Ficha de Heard en NBA.com
 Estadísticas en la NCAA
 Ficha de Gar Heard en ultimatenba.com
 Estadísticas como entrenador

Baloncestistas de Georgia (Estados Unidos)
Baloncestistas de la NBA
Baloncestistas de los Buffalo Braves
Baloncestistas de los Chicago Bulls
Baloncestistas de los Phoenix Suns
Baloncestistas de los San Diego Clippers
Baloncestistas de los Seattle Supersonics
Entrenadores de baloncesto de Estados Unidos
Entrenadores de la NBA
Entrenadores de los Dallas Mavericks
Entrenadores de los Washington Wizards

Gar Heard


තුලනාත්මක දේශපාලනය යනු, සංසන්දනාත්මක මත පදනම්ව භෞතිකවාදී ප‍්‍රවේශයක් අනුව හැඩ ගැසුණු, දේශපාලන විද්‍යාවෙහි උප වර්ගීකරණයකි. ඇත්ත වශයෙන්ම, තුලනාත්මක දේශපාලනයට හරයාත්මක ප‍්‍රවේශයකට වඩා කාර්ය පටිපාටික ප‍්‍රවේශයක් පවති. එය ඉලක්ක කර ගන්නේ "විග‍්‍රහයේ 'කුමක් ද?'යන්න නොව, 'කෙසේද' යන්නයි". වෙනත් වචනවලින් කිවහොත්, තුලනාත්මක දේශපාලනය තම අධ්‍යයනයට බඳුන් වන වස්තුව විසින් නොව, දේශපාලන සංසිද්ධි විග‍්‍රහ කිරීමට යොදා ගන්න ක‍්‍රමවේදය මගින් නිශ්චය කෙරේ. විශේෂිත ක්ෂේත‍්‍රවල භාවිත කිරීමේදී එය වෙනත් වචනවලින් හඳුන්වනු ලැබේ. නිදසුනක් ලෙස තුලනාත්මක ආණ්ඩුව (ආණ්ඩුක‍්‍රම පිළිබඳ සංසන්දනාත්මක අධ්‍යයනය) හෝ තුලනාත්මක විදේශ ප‍්‍රතිපත්තිය (රාජ්‍යයේ ලක්ෂණ හා එහි විදේශ ප‍්‍රතිපත්තියේ ලක්ෂණ අතර භෞතික සබඳතා ස්ථාපනය කිරීම සඳහා විවිධ රාජ්‍යවල විදේශ ප‍්‍රතිපත්ති සංසන්දනය කිරීම) හැඳින්විය හැකිය.

සමහර අවස්ථාවලදී, විශේෂයෙන්ම එක්සත් ජනපදයේ තුලනාත්මක දේශපාලනය යන යෙදුම භාවිත කරන්නේ 'විදේශික රටවල දේශපාලනය' හැඳින්වීමේදී ය. එසේ වුවත්, එම යෙදුම වැරදි යෙදුමක් ලෙස සැලකේ.තුලනාත්මකදේශපාලනයේ පියා වන්නේ ග්‍රීක මහා දාර්ශනික ඇරිස්ටෝටල් ය. තුලනාත්මක අධ්‍යයන ප්‍රවේශ ග්‍රීක යුගයේ සිට අද දක්වා අවධි තුනකින් හඳුනා ගත හැකි ය. එනම්;
      × සම්භාව්‍ය තුලනාත්මක අධ්‍යයන ප්‍රවේශය.
      × විසි වන සියවසේ තුලනාත්මක අධ්‍යයන ප්‍රවේශය.
      × සමකාලීන තුලනාත්මක අධ්‍යයන ප්‍රවේශය.

සටහන්

| Comparative politics
|}

තුලනාත්මක දේශපාලනය


Oakeshott-typologien blev skabt af historikeren og illustratoren Ewart Oakeshott for at definere og katalogisere middelalderlige sværd efter deres form. Den bruges til at kategorisere sværd fra den europæiske middelalder (fra omkring år 1000 til 1500-tallet) i 13 typer, X til XXIII. Oakeshott introducerede den i sin afhandling The Archaeology of Weapons: Arms and Armour from Prehistory to the Age of Chivalry i 1960.

Systemet er en fortsætteles af Jan Petersens typologi af vikingesværd, der i De Norske Vikingsverd (1919), modificeret i 1927 af R. E. M. Wheeler i en typologi, der består af ni typer (I til VII navngivet af Wheeler og udvidet til VIII og IX af Oakeshott).

Oakeshott fandt den hidtidige klassificering upålidelig til den forskning, han havde udført. Han mente, at handel, krig og andre udvekslinger gjorde det vanskeligt entydigt at bestemme et sværds fremstillingsdato, anvendelse, og hvor længe det havde været brugt.

Referencer

Sværd fra Europa

Oakeshott-typologi


Republika Hrvatska i Australija održavaju diplomatske odnose od 13. veljače 1992. Sjedište veleposlanstva je u Canberri.

Veleposlanici
Veleposlanstvo Republike Hrvatske u Australiji osnovano je odlukom predsjednika Republike od 11. ožujka 1992.

Vidi još
Ministarstvo vanjskih i europskih poslova Republike Hrvatske

Vanjske poveznice
 Australija na stranici MVEP-a

Izvori

Australija

Popis hrvatskih veleposlanika u Australiji


An Kuhlhasseltia javanica in uska species han Liliopsida nga ginhulagway ni Johannes Jacobus Smith. An Kuhlhasseltia javanica in nahilalakip ha genus nga Kuhlhasseltia, ngan familia nga Orchidaceae. Waray hini subspecies nga nakalista.

Mga kasarigan

Kuhlhasseltia

Kuhlhasseltia javanica


Güç yüzükleri, J.R.R. Tolkien evreninde yer alan kurgusal büyülü nesneler.

Kurgusal tarihi
Noldor ırkı tarafından ikinci çağda kurulmuş Eregion'da bulunan ve başını Celebrimbor'un çektiği elfler tarafından dövülmüşlerdir. Celebrimbor,  Feanor'un torunuydu ve bu soyun demircilik yeteneği tüm Orta Dünya'da ünlüdür. İkinci çağın 1200 yılında, kendisine Annatar diyen bir adamdan hediyeler almaya başladılar. Annatar onlara demircilik hakkında yeni yetenekler vermeyi önerdi. Elrond ve Gil-Galad'ın uyarılarına rağmen bunu kabul ettiler ve Annatar, Eregion'a geldi. 300 yıl boyunca Annatar'ın yanında kaldılar ve ondan büyülü yüzükler yapmayı öğrendiler. 1500 yılında ilk güç yüzüğü yapıldı ve bunu takip eden yüzyıllarda tam 16 tane güç yüzüğü dövüldü. Her yüzüğün kendine ait değerli bir taşı vardı. Daha sonra Elfler kendilerine üç güç yüzüğü dövdü; Nenya, Narya ve Vilya.

Ama Eregion elflerinin bilmediği bir şey vardı o da aslında Annatar sandıkları adamın gerçekte karanlıklar efendisi Sauron olduğuydu. Mordor'un Hüküm Dağı'nda diğer yüzükleri kendine bağlayabilecek Tek Yüzük'ü dövdü. Onun sayesinde bu güç yüzüklerinin efendisi olacaktı. Yüzüğü bitirdiğinde Elfler onun Sauron olduğunu anladılar ve kendilerine ait olan üç yüzüğü çıkardılar. Sauron öfkelendi ve Mordordan büyük bir orduyla çıkarak Eregiona saldırdı bu saldırı sırasında Celebrimbor öldürüldü ve Eregion yağmalandı. Fakat üç güç yüzüğünü Elfler saklamıştı. 7 yüzük cücelere verildi fakat cüceler de yaratılıştan büyüye karşı dayanıklıydılar, güç yüzükleri onları etkilemedi. Sauron cücelerin üstüne yürüyerek bu yüzükleri geri aldı. İnsanlara verilen  dokuz güç yüzüğü amacına ulaştı ve kullanıcılarını Sauron'un hizmetine soktu. Bu dokuz köle Nazgul ya da yüzük tayfları olarak adlandırıldılar.

Sauron Elfler ve insanların Son İttifak Savaşı'nda yenik düştü. İsildur Tek Yüzük'ü yok etmedi ve Tek Yüzük ona ihanet ederek onun ölümüne yol açtı. Tek Yüzük, Anduin'de kayboldu. Böylece bu üç güç yüzüğü kullanılabilir duruma geldi. Tek Yüzük tekrar ortaya çıktığında bir Hobbit olan Frodo Baggins tarafından, Sauron'un ~5000 (4860) yıl önce dövdüğü yer olan Hüküm Dağı'nda ateşe atılarak yok edildi. Böylece üç güç yüzüğü de dahil tüm güç yüzükleri gücünü kaybetti.

Notlar

Kaynakça

Orta Dünya cisimleri
Kurgusal takılar

Güç yüzükleri


El término «Muse» puede referirse a

Música
 Muse Records, sello discográfico especializado en jazz.
 Muse, banda inglesa de rock alternativo.
 Muse (-), álbum (EP) de Muse.
 Muse (1979), álbum de Grace Jones.
 Muse (2000), álbum de Candy Lo.
 Muse (2012), álbum de Jolin Tsai.
 MuseScore Programa de computadora de código libre para lectura y creación de partituras así como manejo de secuencias y secuenciadores Midi.
 μ's (Muse, pronunciado "mius"); grupo musical de School Idols del proyecto multimedia japonés Love Live! School Idol Project.

Personajes
 Mohamud Muse Hersi, presidente de Puntland, en Somalia.

Bibliotecas digitales
 Project MUSE, base de datos en línea que proporciona acceso al texto completo de publicaciones académicas.

Toponimia
 Muse, ciudad de Birmania.
 Muse, lugar censal del condado de Washington (Pensilvania).

Arquitectura

 Muse, rascacielos residencial situado en Sunny Isles Beach (Florida).

Muse (desambiguación)


An Colpodium fibrosum in uska species han Liliopsida nga ginhulagway ni Ernst Rudolf von Trautvetter. An Colpodium fibrosum in nahilalakip ha genus nga Colpodium, ngan familia nga Poaceae. Waray hini subspecies nga nakalista.

Mga kasarigan

Colpodium

Colpodium fibrosum


Montiano est une frazione située sur la commune de Magliano in Toscana, province de Grosseto, en Toscane, Italie. Au moment du recensement de 2011 sa population était de .

Géographie
Le hameau est situé sur les collines de l'Albegna, le long de la route reliant Magliano à Rispescia, à 18 km au sud-est de la ville de Grosseto.

Histoire
Le village a été construit à la fin du  comme possession de la famille Aldobrandeschi du comté de Soana. Sa fondation est consécutive à l'abandon du château voisin de Montiano Vecchio qui en constitue en fait les vestiges. L'abandon définitif de l'ancien château, construit entre la fin du  et le début du , eut lieu au début du  à la suite d'un violent siège mené par les Siennois, qui obligea les habitants à s'installer à Montiano.

Au cours du , les Siennois réussirent également à conquérir le village de Montiano, sans toutefois causer de graves dégâts ; incorporée au territoire de la République de Sienne, elle est devenue l'un des centres les plus importants de la zone dédiée au pâturage et à l'agriculture .

Au milieu du , après la chute définitive de Sienne, Montiano fut intégré au Grand-Duché de Toscane, suivant désormais son sort.

Monuments
Église San Giovanni Battista ()
Église San Giuseppe ()
Tour de l'horloge, ancienne siège de la famille Aldobrandeschi
 , ruines.
 Murailles de Montiano, fortifications médiévales.

Galerie

Notes et références

Hameau dans la province de Grosseto
Magliano in Toscana

Montiano (Toscane)