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Andrew S. Tanenbaum

Andrew Stuart Tanenbaum, sometimes referred to by the handle ast, is a Dutch / American computer scientist and professor emeritus of computer science at the Vrije Universiteit Amsterdam in the Netherlands. He is best known as the author of MINIX, a free Unix-like operating system for teaching purposes, for his computer science textbooks, regarded as standard texts in the field, he regards his teaching job as his most important work. Since 2004 he has operated Electoral-vote.com, a website dedicated to analysis of polling data in federal elections in the United States as well as the capabilities of Russian Hackers from St Petersburg altering the polling data. Tanenbaum grew up in suburban White Plains, New York, he is Jewish. His paternal grandfather was born in Khorostkiv in the Austro-Hungarian empire, he received his bachelor of Science degree in Physics from MIT in 1965 and his Ph. D. degree in astrophysics from the University of California, Berkeley in 1971. Tanenbaum served as a lobbyist for the Sierra Club.

He moved to the Netherlands to live with his wife, Dutch, but he retains his United States citizenship. He teaches courses about Computer Organization and Operating Systems and supervises the work of Ph. D. candidates at the VU University Amsterdam. On 9 July 2014, he announced his retirement. Tanenbaum is well recognized for his textbooks on computer science, they include: Computer Networks, co-authored with David J. Wetherall Operating Systems: Design and Implementation, co-authored with Albert Woodhull Modern Operating Systems Distributed Operating Systems Structured Computer Organization Distributed Systems: Principles and Paradigms, co-authored with Maarten van SteenHis book, Operating Systems: Design and Implementation and MINIX were Linus Torvalds' inspiration for the Linux kernel. In his autobiography Just for Fun, Torvalds describes it as "the book that launched me to new heights", his books have been translated into many languages including Arabic, Bulgarian, Dutch, German, Hebrew, Italian, Korean, Mexican Spanish, Polish, Romanian, Russian and Spanish.

They are used at universities around the world. Tanenbaum has had a number of Ph. D. students who themselves have gone on to become known computer science researchers. These include: Henri Bal, professor at the Vrije Universiteit in Amsterdam Frans Kaashoek, professor at MIT Sape Mullender, researcher at Bell Labs Robbert van Renesse, professor at Cornell University Leendert van Doorn, distinguished engineer at the Microsoft Corporation Werner Vogels, Chief Technology Officer at Amazon.com In the early 1990s, the Dutch government began setting up a number of thematically oriented research schools that spanned multiple universities. These schools were intended to bring professors and Ph. D. students from different Dutch universities together to help them cooperate and enhance their research. Tanenbaum was one of the cofounders and first Dean of the Advanced School for Computing and Imaging; this school consisted of nearly 200 faculty members and Ph. D. students from the Vrije Universiteit, University of Amsterdam, Delft University of Technology, Leiden University.

They were working on problems in advanced computer systems such as parallel computing and image analysis and processing. Tanenbaum remained dean for 12 years, until 2005, when he was awarded an Academy Professorship by the Royal Netherlands Academy of Arts and Sciences, at which time he became a full-time research professor. ASCI has since grown to include researchers from nearly a dozen universities in The Netherlands and France. ASCI offers Ph. D. level courses, has an annual conference, runs various workshops every year. The Amsterdam Compiler Kit is a toolkit for producing portable compilers, it was started sometime before 1981 and Andrew Tanenbaum was the architect from the start until version 5.5. In 1987, Tanenbaum wrote a clone of UNIX, called MINIX, for the IBM PC, it was targeted at others who wanted to learn how an operating system worked. He wrote a book that listed the source code in an appendix and described it in detail in the text; the source code itself was available on a set of floppy disks.

Within three months, a Usenet newsgroup, comp.os.minix, had sprung up with over 40,000 subscribers discussing and improving the system. One of these subscribers was a Finnish student named Linus Torvalds who began adding new features to MINIX and tailoring it to his own needs. On October 5, 1991, Torvalds announced his own kernel, called Linux, which used the MINIX file system but is not based on MINIX code. Although MINIX and Linux have diverged, MINIX continues to be developed, now as a production system as well as an educational one; the focus is on building a modular and secure operating system. The system is based with only 5000 lines of code running in kernel mode; the rest of the operating system runs as a number of independent processes in user mode, including processes for the file system, process manager, each device driver. The system continuously monitors each of these processes, when a failure is detected is capable of automatically replacing the failed process without a reboot, without disturbing running programs, without the user noticing.

MINIX 3, as the current version is called, is available under the BSD license for free. Tanenbaum has been involved in numerous other research projects in the areas of operating systems, distributed systems, ubiquitous computing as super

Flávia Delaroli

Flávia Renata Delaroli Cazziolato is an Olympic and National Record holding freestyle swimmer from Brazil. A resident of São Paulo, she represented her native country at the 2008 Olympics. At 15 years old, Dalaroli took part in the 1999 Pan American Games in Winnipeg, where she was part of the bronze medal winning team in the 4×100-metre freestyle relay, she placed 4th individually in the 50-metre freestyle race. Three years Delaroli competed at the 2002 FINA World Swimming Championships in Moscow, where she went to the 4×100-metre freestyle relay final taking 8th place with her teammates, she placed 19th in the 50-metre freestyle, 33rd in the 100-metre freestyle. At the 2003 World Aquatics Championships in Barcelona, Delaroli finished 18th in the 50-metre freestyle, 24th in the 100-metre freestyle, 14th in the 4×100-metre freestyle relay, 14th in the 4×100-metre medley. Delaroli had her first major international podium placement at the 2003 Pan American Games in Santo Domingo, taking the silver medal in the 50-metre freestyle and the bronze in the 4×100-metre freestyle relay.

She finished at 4th place in the 100-metre freestyle and in the 4×100-metre medley. Delaroli competed at the 2004 Summer Olympics in Athens, where she reached the 50-metre freestyle final, finishing in 8th place, she placed 12th in the 4×100-metre freestyle relay. On September 11, 2004, along with teammates Talita Ribeiro, Mariana Katsuno and Júlia Leão, Delaroli became the South American record holder in the 4×100-metre medley with a time of 4:09.26. At the 2004 FINA World Swimming Championships in Indianapolis, Delaroli nearly won a medal, finishing in 4th place in the 50-metre freestyle, just 2 hundredths of a second behind the bronze medalist, she came in 4th place in the 4×100-metre freestyle. In this relay, on October 10, 2004, Delaroli broke her second South American record, with a time of 3:41.52, along with Flávia Jesus, Rebeca Gusmão and Tatiana Lemos. At the 2005 World Aquatics Championships in Montreal, Delaroli placed 12th in the 50-metre freestyle event. On December 16, 2005, Delaroli broke the South American record in the 50-metre freestyle with a time of 24.36 seconds.

She came in 12th in the same event at the 2006 FINA World Swimming Championships in Shanghai, took bronze in the event at the 2006 Pan Pacific Swimming Championships in Canada. At the 2007 World Aquatics Championships in Melbourne, Delaroli finished 23rd in the 50-metre freestyle and 32nd in the 100-metre freestyle; that year, at the 2007 Pan American Games in Rio de Janeiro, Delaroli won the silver medal in the 100-metre freestyle and took bronze in the 50-metre freestyle. She placed 4th in the 50-metre freestyle competition, but when Rebeca Gusmão lost her gold on a finding that she had used performance-enhancing drugs, the gold was given to the silver medalist, the silver to the bronze medalist, Delaroli received the bronze, she would have won the silver medal in the 4×100-metre freestyle, the bronze medal in the 4×100-metre medley, but these medals were annulled by Gusmão's doping. At the 2008 Summer Olympics in Beijing, Delaroli finished 22nd in the 50-metre freestyle, she got the 13th place in the 4×100-metre freestyle.

On August 9, 2008, Delaroli became the South American record holder in the 4×100-metre freestyle securing a time of 3:42.85 together with Tatiana Lemos, Michelle Lenhardt and Monique Ferreira. She received the index for placement into the 2009 World Aquatics Championships in the 50-metre freestyle, with a new South American record, obtained in Palhoça on December 12, 2008. At the subsequent World Aquatics Championships in Rome, Delaroli finished 25th in the 50-metre freestyle. On December 17, 2009, Delaroli broke the Brazilian record in the 50-metre freestyle Olympic pool with a time of 24.98 seconds. Delaroli competed at the 2010 Pan Pacific Swimming Championships in Irvine, placing 7th in the 50-metre freestyle, 34th in the 100-metre freestyle. Delaroli swam at the 2010 FINA World Swimming Championships in Dubai, where she finished 12th in the 50-metre freestyle, 22nd in the 100-metre freestyle, 8th in the 4×100-metre freestyle final. In this relay, she swam with Lemos and Julyana Kury, her team broke the South American record with a time of 3:35.95.

At the 2011 World Aquatics Championships in Shanghai, she placed 18th in the 50-metre freestyle and 13th in the 4×100-metre freestyle. At the 2011 Pan American Games in Guadalajara, Delaroli won the silver medal in the 4×100-metre freestyle, she placed 6th in the 50-metre freestyle. Delaroli competed for the last time at the 2012 FINA World Swimming Championships in Istanbul, where she made the 50-metre freestyle final, finishing in 8th place, the 4×100-metre freestyle final, finishing in 6th place. List of South American records in swimming List of Brazilian records in swimming UOL Profile

List of pizza chains

This list of pizza chains includes notable pizzerias and pizza chains. Pizza is a dish of Neapolitan origin and cuisine, made with an oven-baked, flat round bread, covered with tomatoes or a tomato-based sauce and mozzarella cheese. Other toppings are added according to culture, or personal preference. A restaurant or takeout where pizzas are made and sold as main food is called a pizzeria or “pizza parlor” in English; the term pizza pie is a dialectal, pie is used for simplicity in some contexts, such as among pizzeria staff. Boston Pizza California Pizza Kitchen Chuck E. Cheese's Dodo Pizza Domino's Pizza Figaro's Pizza Little Caesars Papa John's Pizza The Pizza Company Pizza Corner Pizza Hut Pizza Inn PizzaExpress Sarpino's Pizzeria Sbarro Shakey's Pizza Telepizza Uno Chicago Grill Vapiano Yellow Cab Pizza Co. Eagle Boys Pizza Capers Pizza Haven La Porchetta 241 Pizza Boston Pizza Freshslice Pizza Gabriel Pizza Greco Pizza Restaurant King of Donair Mikes Mother's Pizza Panago Pizza 73 Pizza Delight Pizza Nova Pizzaiolo Pizza Pizza Topper's Pizza Kro's Nest Origus Jeno's Pizza Kotipizza Speed Rabbit Pizza Smokin' Joes Four Star Pizza Big Apple Pizza Rossopomodoro Spizzico Aoki's Pizza Pizza California Pizza-La Čili Benedetti's Pizza Hell Pizza Peppes Pizza Greenwich Pizza Yellow Cab Pizza Co.

Dodo Pizza Debonairs Pizza Panarottis Roman's Pizza Mr. Pizza Telepizza Alleycat's Pizza The Pizza Company Mario's Pizzeria Pizza Celentano Ask Bella Italia Carluccio's easyPizza Franco Manca PizzaExpress Prezzo Strada Tops Pizza Zizzi List of pizza franchises List of casual dining restaurant chains List of coffeehouse chains List of fast food restaurant chains List of ice cream parlor chains Lists of restaurants

Amir Sultan

Amir Sultan was Amir Kulal Shamsuddin’s grandson. He was invited by the Ottoman Sultan Bayezid I to Anatolia. Bayezid I had a daughter named " Hundi Fatema Sultan Hatun" from his marriage with Daulat Khatun, married to Amir Sultan. Daulat Khatun was a descendant of Jalal ud-Din Rumi. By the end of fourteenth century Timur and Bayezid I had emerged as two superpowers in Asia and Europe, making the confrontation between two a matter of time. Timur took the lead and conquered the Ottoman city of Sivas, disseminating the local population in his trademark style. At the same time two princes, Ahmad Jalair and Kara Yosuf sought for protection at Bayezid I's court, their territories had been conquered by Timur. Timur Bayezid I refused. Bayezid I went a step further and prepared for an attack on Timur’s territory. At this point his son-in-law Amir Sultan advised him against the move knowing well the penchant and proficiency of Timur and his soldiers in a battlefield. However, his genteel council fell on deaf ears.

Instigated and incited by the two princes Bayezid I seized Erzurum, under Timur’s rule. To Timur this was declaration of war and in his symbolic manner he started conquering Ottoman cities one by one with whirlwind speed. Bayezid I took his army to stop Timur and the two goliaths met at the plains of the Battle of Ankara on 20 July 1402. Although Bayezid I had made a fierce reputation in Europe as a brilliant general and ferocious warrior but he was no match for Timur whose years in battlefield far exceeded Bayazid’s age; the Timurid attack was ruthless and merciless and in one word, Timur “annihilated” the Ottoman army, taking Bayezid I, his children and princes as captives. Amir Sultan had decided not to be a party of the war, it was because of the family associations with the Barlas tribe he decided not to be associated with the either side while the state-of-war lasted between the two sovereigns. It might have been this decision coupled with the fact that his family was regarded as mentors by the Timurid Dynasty which meant he did not share the same fate as his in-laws.

After the battle Amir Sultan returned to his native soil at Vabkent. His children went to Chinese Turkistan. After Babur established the Mughal Empire his descendants moved to India. Among them Shah Jamal, Shah La’al, Shah Abbas, Shah Altaf are the notables

Nonconvex great rhombicosidodecahedron

In geometry, the nonconvex great rhombicosidodecahedron is a nonconvex uniform polyhedron, indexed as U67. It is called the quasirhombicosidodecahedron, it is given a Schläfli symbol t0,2. Its vertex figure is a crossed quadrilateral; this model shares the name with the convex great rhombicosidodecahedron known as the truncated icosidodecahedron. Cartesian coordinates for the vertices of a nonconvex great rhombicosidodecahedron are all the permutations of where τ = /2 is the golden ratio, it shares its vertex arrangement with the truncated great dodecahedron, with the uniform compounds of 6 or 12 pentagonal prisms. It additionally shares its edge arrangement with the great dodecicosidodecahedron, the great rhombidodecahedron; the great deltoidal hexecontahedron is a nonconvex isohedral polyhedron. It is the dual of the nonconvex great rhombicosidodecahedron, it is visually identical to the Great rhombidodecacron. It has 60 intersecting cross quadrilateral faces, 120 edges, 62 vertices, it is called a great strombic hexecontahedron.

List of uniform polyhedra Wenninger, Dual Models, Cambridge University Press, doi:10.1017/CBO9780511569371, ISBN 978-0-521-54325-5, MR 0730208 Weisstein, Eric W. "Great rhombicosidodecahedron". MathWorld. Weisstein, Eric W. "Great deltoidal hexecontahedron". MathWorld. Uniform polyhedra and duals

Antiparticle

In particle physics, every type of particle has an associated antiparticle with the same mass but with opposite physical charges. For example, the antiparticle of the electron is the antielectron. While the electron has a negative electric charge, the positron has a positive electric charge, is produced in certain types of radioactive decay; the opposite is true: the antiparticle of the positron is the electron. Some particles, such as the photon, are their own antiparticle. Otherwise, for each pair of antiparticle partners, one is designated as normal matter, the other as antimatter. Particle–antiparticle pairs can annihilate each other, producing photons. For example, the positrons produced in natural radioactive decay annihilate themselves with electrons, producing pairs of gamma rays, a process exploited in positron emission tomography; the laws of nature are nearly symmetrical with respect to particles and antiparticles. For example, an antiproton and a positron can form an antihydrogen atom, believed to have the same properties as a hydrogen atom.

This leads to the question of why the formation of matter after the Big Bang resulted in a universe consisting entirely of matter, rather than being a half-and-half mixture of matter and antimatter. The discovery of Charge Parity violation helped to shed light on this problem by showing that this symmetry thought to be perfect, was only approximate; because charge is conserved, it is not possible to create an antiparticle without either destroying another particle of the same charge, or by the simultaneous creation of both a particle and its antiparticle, which can occur in particle accelerators such as the Large Hadron Collider at CERN. Although particles and their antiparticles have opposite charges, electrically neutral particles need not be identical to their antiparticles; the neutron, for example, is made out of quarks, the antineutron from antiquarks, they are distinguishable from one another because neutrons and antineutrons annihilate each other upon contact. However, other neutral particles are their own antiparticles, such as photons, Z0 bosons, π0 mesons, hypothetical gravitons and some hypothetical WIMPs.

In 1932, soon after the prediction of positrons by Paul Dirac, Carl D. Anderson found that cosmic-ray collisions produced these particles in a cloud chamber— a particle detector in which moving electrons leave behind trails as they move through the gas; the electric charge-to-mass ratio of a particle can be measured by observing the radius of curling of its cloud-chamber track in a magnetic field. Positrons, because of the direction that their paths curled, were at first mistaken for electrons travelling in the opposite direction. Positron paths in a cloud-chamber trace the same helical path as an electron but rotate in the opposite direction with respect to the magnetic field direction due to their having the same magnitude of charge-to-mass ratio but with opposite charge and, opposite signed charge-to-mass ratios; the antiproton and antineutron were found by Emilio Segrè and Owen Chamberlain in 1955 at the University of California, Berkeley. Since the antiparticles of many other subatomic particles have been created in particle accelerator experiments.

In recent years, complete atoms of antimatter have been assembled out of antiprotons and positrons, collected in electromagnetic traps. Solutions of the Dirac equation contained negative energy quantum states; as a result, an electron could always fall into a negative energy state. Worse, it could keep radiating infinite amounts of energy because there were infinitely many negative energy states available. To prevent this unphysical situation from happening, Dirac proposed that a "sea" of negative-energy electrons fills the universe occupying all of the lower-energy states so that, due to the Pauli exclusion principle, no other electron could fall into them. Sometimes, one of these negative-energy particles could be lifted out of this Dirac sea to become a positive-energy particle. But, when lifted out, it would leave behind a hole in the sea that would act like a positive-energy electron with a reversed charge; these holes were interpreted as "negative-energy electrons" by Paul Dirac and by mistake he identified them with protons in his 1930 paper A Theory of Electrons and Protons However, these "negative-energy electrons" turned out to be positrons, not protons.

This picture implied an infinite negative charge for the universe—a problem of which Dirac was aware. Dirac tried to argue. Another difficulty was the difference in masses of the proton. Dirac tried to argue that this was due to the electromagnetic interactions with the sea, until Hermann Weyl proved that hole theory was symmetric between negative and positive charges. Dirac predicted a reaction e− + p+ → γ + γ, where an electron and a proton annihilate to give two photons. Robert Oppenheimer and Igor Tamm proved. A year in 1931, Dirac modified his theory and postulated the positron, a new particle of the same mass as the electron; the discovery of this particle the next year removed the last two objections to his theory. Within Dirac's theory, the problem of infinite charge of the universe remains; some bosons