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J. W. J. Williams
John William Joseph Williams (2 September 1930 – 29 September 2012) was a Welsh-Canadian computer scientist best known for inventing in 1964 heapsort and the binary heap data structure. He was born in Chippenham, Wiltshire''England & Wales, Civil Registration Birth Index, 1916-2007'' and spent the latter part of his career in Canada, moving to Kanata, Ottawa in 1972 and working for Bell-Northern Research and Nortel Nortel Networks Corporation (Nortel), formerly Northern Telecom Limited, was a Canadian multinational telecommunications and data networking equipment manufacturer headquartered in Ottawa, Ontario, Canada. It was founded in Montreal, Quebec, ... before retiring in 1995. References External links * 1930 births 2012 deaths British computer scientists Canadian computer scientists British emigrants to Canada {{Canada-scientist-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1939 England And Wales Register
The National Registration Act 1939 was an Act of Parliament in the United Kingdom. The initial National Registration Bill was introduced to Parliament as an emergency measure at the start of the Second World War. The Act provided for the establishment of a constantly-maintained National Register of the civilian population of the United Kingdom and the Isle of Man, and for the issuance of identity cards based on data held in the register, and required civilians to present their identity cards on demand to police officers and other authorised persons. Following the passing of the Act by Parliament on 5 September 1939, registrations and the issuing of identity cards commenced on 29 September. Registration and identity cards Every man, woman and child had to carry an identity (ID) card at all times and the cards would include the following information: *Name *Sex *Date of birth (and thus age) *Occupation, profession, trade or employment. The Register had also collected informati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heapsort
In computer science, heapsort is a comparison-based sorting algorithm. Heapsort can be thought of as an improved selection sort: like selection sort, heapsort divides its input into a sorted and an unsorted region, and it iteratively shrinks the unsorted region by extracting the largest element from it and inserting it into the sorted region. Unlike selection sort, heapsort does not waste time with a linear-time scan of the unsorted region; rather, heap sort maintains the unsorted region in a heap data structure to more quickly find the largest element in each step. Although somewhat slower in practice on most machines than a well-implemented quicksort, it has the advantage of a more favorable worst-case runtime (and as such is used by Introsort as a fallback should it detect that quicksort is becoming degenerate). Heapsort is an in-place algorithm, but it is not a stable sort. Heapsort was invented by J. W. J. Williams in 1964. This was also the birth of the heap, presented ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Binary Heap
A binary heap is a heap data structure that takes the form of a binary tree. Binary heaps are a common way of implementing priority queues. The binary heap was introduced by J. W. J. Williams in 1964, as a data structure for heapsort. A binary heap is defined as a binary tree with two additional constraints: *Shape property: a binary heap is a '' complete binary tree''; that is, all levels of the tree, except possibly the last one (deepest) are fully filled, and, if the last level of the tree is not complete, the nodes of that level are filled from left to right. *Heap property: the key stored in each node is either greater than or equal to (≥) or less than or equal to (≤) the keys in the node's children, according to some total order. Heaps where the parent key is greater than or equal to (≥) the child keys are called ''max-heaps''; those where it is less than or equal to (≤) are called ''min-heaps''. Efficient ( logarithmic time) algorithms are known for the two ope ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communications Of The ACM
''Communications of the ACM'' is the monthly journal of the Association for Computing Machinery (ACM). It was established in 1958, with Saul Rosen as its first managing editor. It is sent to all ACM members. Articles are intended for readers with backgrounds in all areas of computer science and information systems. The focus is on the practical implications of advances in information technology and associated management issues; ACM also publishes a variety of more theoretical journals. The magazine straddles the boundary of a science magazine, trade magazine, and a scientific journal. While the content is subject to peer review, the articles published are often summaries of research that may also be published elsewhere. Material published must be accessible and relevant to a broad readership. From 1960 onward, ''CACM'' also published algorithms, expressed in ALGOL. The collection of algorithms later became known as the Collected Algorithms of the ACM. See also * ''Journal of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chippenham
Chippenham is a market town in northwest Wiltshire, England. It lies northeast of Bath, west of London, and is near the Cotswolds Area of Natural Beauty. The town was established on a crossing of the River Avon and some form of settlement is believed to have existed there since before Roman times. It was a royal vill, and probably a royal hunting lodge, under Alfred the Great. The town continued to grow when the Great Western Railway arrived in 1841. The town had a population of 36,548 in 2021. Geography Location Chippenham is in western Wiltshire, at a prominent crossing of the River Avon, between the Marlborough Downs to the east, the southern Cotswolds to the north and west and Salisbury Plain to the southeast. The town is surrounded by sparsely populated countryside and there are several woodlands in or very near the town, such as Bird's Marsh, Vincients Wood and Briars Wood. Suburbs Suburbs include Cepen Park (North & South), Hardenhuish, Monkton, Lowden, Pewsh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wiltshire
Wiltshire (; abbreviated Wilts) is a historic and ceremonial county in South West England with an area of . It is landlocked and borders the counties of Dorset to the southwest, Somerset to the west, Hampshire to the southeast, Gloucestershire to the north, Oxfordshire to the northeast and Berkshire to the east. The county town was originally Wilton, after which the county is named, but Wiltshire Council is now based in the county town of Trowbridge. Within the county's boundary are two unitary authority areas, Wiltshire and Swindon, governed respectively by Wiltshire Council and Swindon Borough Council. Wiltshire is characterised by its high downland and wide valleys. Salisbury Plain is noted for being the location of the Stonehenge and Avebury stone circles (which together are a UNESCO Cultural and World Heritage site) and other ancient landmarks, and as a training area for the British Army. The city of Salisbury is notable for its medieval cathedral. Swindon is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kanata, Ontario
Kanata (, ) is a suburb of Ottawa, Ontario, Canada. It is located about west of the city's downtown core. As of 2021, Kanata had an urban population of 137,118. Before it was amalgamated into Ottawa in 2001, it was one of the fastest-growing cities in Canada and the fastest-growing community in Eastern Ontario. Located just to the west of the National Capital Commission Greenbelt, it is one of the largest of several communities that surround central Ottawa. History The area that is today Kanata was originally part of the March Township, and was first settled by Europeans in the early 19th century. One site dating from this era is Pinhey's Point. It remained mainly agricultural until the 1960s when it became the site of heavy development. Modern Kanata is largely the creation of Bill Teron, a developer and urban planner who purchased over of rural land and set about building a model community. Unlike other suburbs, Kanata was designed to have a mix of densities and co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ottawa
Ottawa (, ; Canadian French: ) is the capital city of Canada. It is located at the confluence of the Ottawa River and the Rideau River in the southern portion of the province of Ontario. Ottawa borders Gatineau, Quebec, and forms the core of the Ottawa–Gatineau census metropolitan area (CMA) and the National Capital Region (NCR). Ottawa had a city population of 1,017,449 and a metropolitan population of 1,488,307, making it the fourth-largest city and fourth-largest metropolitan area in Canada. Ottawa is the political centre of Canada and headquarters to the federal government. The city houses numerous foreign embassies, key buildings, organizations, and institutions of Canada's government, including the Parliament of Canada, the Supreme Court, the residence of Canada's viceroy, and Office of the Prime Minister. Founded in 1826 as Bytown, and incorporated as Ottawa in 1855, its original boundaries were expanded through numerous annexations and were ultimately ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bell-Northern Research
Bell-Northern Research (BNR) was a telecommunications research and development company established In 1971 when Bell Canada and Northern Electric combined their R&D organizations. It was jointly owned by Bell Canada and Northern Telecom. BNR was absorbed into Nortel Networks when that company changed its name from Northern Telecom in the mid-1990s. BNR was based at the Carling Campus in Ottawa, Ontario, Canada, with campuses at locations around the world, including Research Triangle Park, North Carolina; Richardson, Texas; Ann Arbor, Michigan; and Harlow and Maidenhead, United Kingdom. Bell-Northern Research pioneered the development of digital technology, and created the first practical digital PBX, (SL1), and central office ( DMS). Under the direction of then Nortel Chief Officer, John Roth, BNR lost its separate identity in the 1990s, and was folded into the Nortel R&D organization. History For much of its early history, Bell Canada operated as the Canadian division of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nortel
Nortel Networks Corporation (Nortel), formerly Northern Telecom Limited, was a Canadian Multinational corporation, multinational telecommunications and data networking equipment manufacturer headquartered in Ottawa, Ontario, Canada. It was founded in Montreal, Quebec, in 1895 as the Northern Electric and Manufacturing Company. Until an antitrust settlement in 1949, Northern Electric was owned principally by Bell Canada and the Western Electric, Western Electric Company of the Bell System, producing large volumes of telecommunication equipment based on licensed Western Electric designs. At its height, Nortel accounted for more than a third of the total valuation of all companies listed on the Toronto Stock Exchange (TSX), employing 94,500 people worldwide. In 2009, Nortel filed for bankruptcy protection in Canada and the United States, triggering a 79% decline of its corporate stock price. The bankruptcy case was the List of corporate collapses and scandals, largest in Canadian h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1930 Births
Year 193 ( CXCIII) was a common year starting on Monday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Sosius and Ericius (or, less frequently, year 946 ''Ab urbe condita''). The denomination 193 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years. Events By place Roman Empire * January 1 – Year of the Five Emperors: The Roman Senate chooses Publius Helvius Pertinax, against his will, to succeed the late Commodus as Emperor. Pertinax is forced to reorganize the handling of finances, which were wrecked under Commodus, to reestablish discipline in the Roman army, and to suspend the food programs established by Trajan, provoking the ire of the Praetorian Guard. * March 28 – Pertinax is assassinated by members of the Praetorian Guard, who storm the imperial palace. The Empire is a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2012 Deaths
This is a list of deaths of notable people, organised by year. New deaths articles are added to their respective month (e.g., Deaths in ) and then linked here. 2022 2021 2020 2019 2018 2017 2016 2015 2014 2013 2012 2011 2010 2009 2008 2007 2006 2005 2004 2003 2002 2001 2000 1999 1998 1997 1996 1995 1994 1993 1992 1991 1990 1989 1988 1987 See also * Lists of deaths by day * Deaths by year {{DEFAULTSORT:deaths by year ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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