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Linked list

In computer science, a linked list is a linear collection of data elements, whose order is not given by their physical placement in memory. Instead, each element points to the next, it is a data structure consisting of a collection of nodes. In its most basic form, each node contains: data, a reference to the next node in the sequence; this structure allows for efficient insertion or removal of elements from any position in the sequence during iteration. More complex variants add additional links, allowing more efficient insertion or removal of nodes at arbitrary positions. A drawback of linked lists is. Faster access, such as random access, is not feasible. Arrays have better cache locality compared to linked lists. Linked lists are among most common data structures, they can be used to implement several other common abstract data types, including lists, queues, associative arrays, S-expressions, though it is not uncommon to implement those data structures directly without using a linked list as the basis.

The principal benefit of a linked list over a conventional array is that the list elements can be inserted or removed without reallocation or reorganization of the entire structure because the data items need not be stored contiguously in memory or on disk, while restructuring an array at run-time is a much more expensive operation. Linked lists allow insertion and removal of nodes at any point in the list, allow doing so with a constant number of operations by keeping the link previous to the link being added or removed in memory during list traversal. On the other hand, since simple linked lists by themselves do not allow random access to the data or any form of efficient indexing, many basic operations—such as obtaining the last node of the list, finding a node that contains a given datum, or locating the place where a new node should be inserted—may require iterating through most or all of the list elements; the advantages and disadvantages of using linked lists are given below. Linked list are dynamic, so the length of list can increase or decrease as necessary.

Each node does not follow the previous one physically in the memory. They use more memory than arrays because of the storage used by their pointers. Nodes in a linked list must be read in order from the beginning as linked lists are inherently sequential access. Nodes are stored noncontiguously increasing the time periods required to access individual elements within the list with a CPU cache. Difficulties arise in linked lists. For instance, singly-linked lists are cumbersome to navigate backward and while doubly linked lists are somewhat easier to read, memory is consumed in allocating space for a back-pointer. Linked lists were developed in 1955–1956 by Allen Newell, Cliff Shaw and Herbert A. Simon at RAND Corporation as the primary data structure for their Information Processing Language. IPL was used by the authors to develop several early artificial intelligence programs, including the Logic Theory Machine, the General Problem Solver, a computer chess program. Reports on their work appeared in IRE Transactions on Information Theory in 1956, several conference proceedings from 1957 to 1959, including Proceedings of the Western Joint Computer Conference in 1957 and 1958, Information Processing in 1959.

The now-classic diagram consisting of blocks representing list nodes with arrows pointing to successive list nodes appears in "Programming the Logic Theory Machine" by Newell and Shaw in Proc. WJCC, February 1957. Newell and Simon were recognized with the ACM Turing Award in 1975 for having "made basic contributions to artificial intelligence, the psychology of human cognition, list processing"; the problem of machine translation for natural language processing led Victor Yngve at Massachusetts Institute of Technology to use linked lists as data structures in his COMIT programming language for computer research in the field of linguistics. A report on this language entitled "A programming language for mechanical translation" appeared in Mechanical Translation in 1958. LISP, standing for list processor, was created by John McCarthy in 1958 while he was at MIT and in 1960 he published its design in a paper in the Communications of the ACM, entitled "Recursive Functions of Symbolic Expressions and Their Computation by Machine, Part I".

One of LISP's major data structures is the linked list. By the early 1960s, the utility of both linked lists and languages which use these structures as their primary data representation was well established. Bert Green of the MIT Lincoln Laboratory published a review article entitled "Computer languages for symbol manipulation" in IRE Transactions on Human Factors in Electronics in March 1961 which summarized the advantages of the linked list approach. A review article, "A Comparison of list-processing computer languages" by Bobrow and Raphael, appeared in Communications of the ACM in April 1964. Several operating systems developed by Technical Systems Consultants used singly linked lists as file structures. A directory entry pointed to the first sector of a file, succeeding portions of the file were located by traversing pointers. Systems using this technique included Flex, mini-Flex, Flex9. A variant developed by TSC for and marketed by Smoke Signal Broadcasting in California, used doubly linked lists in the same manner.

The TSS/360 operating system, developed by IBM for the System 360/370 machines

Lisa Seeman

Lisa Seeman is an inventor and an entrepreneur and has been instrumental in creating standards for interoperability and accessibility. She works for Athena ICT. Seeman headed. In 2006, UB Access was sold to Aequus Technologies Corp. and she became chief technology officer for Aequus DPS and served as managing director of UB Access' operations in Israel, involved in content adaptation for elearning and localization. She moved to EFP Consulting, creating research and development proposals and international consortiums within the FP7 framework of the European Commission. Topics included: Methodology to determine issues of complexity that effect the adoption of technology. Seeman is the facilitator of the Cognitive and Learning Disabilities Accessibility Task Force of the web accessibility initiative of the W3C, it aims to improve the user experience for people with cognitive disabilities. Seeman has been an invited expert for the W3C since 1999. In 2006 she became the original author and editor of the Roles for Accessible Rich Internet Applications specification and the States and Properties Module for Accessible Rich Internet Applications which became the specifications for Accessible Rich Internet Applications for the W3C.

She is a named contributor to the Web Content Accessibility Guidelines specification, although she headed a controversial formal objection to WCAG's claim that WCAG 2.0 will address requirements for people with learning disabilities and cognitive limitations. Seeman was involved with ISOC IL, ACLIP, has worked with accessibility groups of organizations such as Dublin Core and ISO, she published on topics such as dyslexia and society, the semantic web, web accessibility, device independence. She gives presentations at conferences and venues such as W3C events, standards organizations, universities and NGOs. WCAG 2.0 Athena Technologies

Shanes Park, New South Wales

Shanes Park is a suburb of Sydney, in the state of New South Wales, Australia. Shanes Park is located 50 kilometres west of the Sydney central business district, in the local government area of the City of Blacktown and is part of the Greater Western Sydney region. In 1960, the eastern portion of Shane's Park was purchased by the commonwealth government to house an air navigational facility. Substantial heritage from this facility remains to this day; as this required little space, most areas of the site were retained as intact bushland, while other areas regenerated naturally. The 560 site known as'Shane's Park' now comprises one of the largest remaining woodlands in the Cumberland Plain; the Shane's Park woodland is the most intact remnant of the vegetation which once covered western Sydney, contains a wide range of vulnerable and critically endangered flora and ecological communities. The site is renowned for its woodland bird fauna, including the speckled warbler; the site is not open to public access.

The present owners, Air Services Australia, consider the site surplus to their needs, propose to hand over ownership as a public reserve to the New South Wales government. The Deed of Agreement for transfer requires the NSW government to gazette the land as regional park; this requirement has caused conflict with some community organisations. The National Parks & Wildlife Act outlines the purpose of a regional park as being for recreation only, does not expect management for wildlife conservation. If the deed is signed, it is that the site will be amalgamated into the adjoining Wianamatta Regional Park. Opponents to regional park gazettal for Shane's Park have opposed the plans for Wianamatta Regional Park, which provide for commercial recreational opportunities and the fencing and culling of native fauna populations for public safety.'Save Shane's Park Woodland'

William Pearly Oliver

William Pearly Oliver worked at the Cornwallis Street Baptist Church for twenty-five years and was instrumental in developing the four leading organizations to support Black Nova Scotians in the 20th century: Nova Scotia Association for the Advancement of Colored People, the Nova Scotia Human Rights Commission, the Black United Front and the Black Cultural Centre. He was instrumental in supporting the case of Viola Desmond. Oliver was awarded the Order of Canada in 1984, his wife Pearleen Borden Oliver was a strong advocate for social justice. Black Nova Scotians Bridglal Pachai Dr. William Pearly Oliver and the search for black self-identity in Nova Scotia Black Cultural Centre - Wall of Honour Acadia University - Wolfville Historical Society

Intangible good

An intangible good is a good that does not have a physical nature, as opposed to a physical good. Digital goods such as downloadable music, mobile apps or virtual goods used in virtual economies are all examples of intangible goods. In an digitized world, intangible goods play a more and more important role in the economy. Anything, in a digital form and deliverable on the Internet can be considered an intangible good. In ordinary sense, an intangible good should not be confused with a service, since a good is an object, whereas a service is an activity or labor. So a haircut is a service, not an intangible good. An intangible good is just a good, intangible, i.e. incapable of being touched. A good is any of the following: In pure economics, a good is any object or service that increases utility, directly or indirectly. According to this definition A, intangible goods include services. In macroeconomics and accounting, a good is contrasted with a service. A good is defined as an object whose consumption increases the utility of the consumer, for which the quantity demanded exceeds the quantity supplied at zero price.

In the most restricted sense, some people argue all objects are physical, the resulting definition B leaves no place for intangible goods and classifies all of them as services. In a more ordinary sense, a middle ground between definitions A and B, an object can be intangible, we have the definition C of good. According to definition A, a printed book, a piece of music downloaded from the Internet, a haircut are all considered a good though and are intangible. According to definition B, only is a good and both and are considered to be a service. By definition C, is tangible good, is intangible good and is a service. A different way to look at this distinction is to consider the ownership factor. If person A requests a design and person B fulfills the request and delivers the design through the Internet, the design is both a service and a digital good, it is a service. If what person A bought from person B is a service person A should assume ownership of the design, a digital good, it is analogous to buying a book from a bookstore: the buyer has the right to use that book but does not own the copyright, whereas if a writer is hired to write a book for someone the latter will have the copyright.

Bannock, Graham et al... Dictionary of Economics, Penguin Books. Milgate, Murray, "goods and commodities," The New Palgrave: A Dictionary of Economics, v. 2, pp. 546–48. Includes historical and contemporary uses of the terms in economics

Humphrey Coliseum

Humphrey Coliseum is a 10,575-seat multi-purpose arena located on the campus of Mississippi State University, just outside Starkville, that opened for the 1975-76 basketball season. Nicknamed The Hump, it is home to women's basketball teams, it is the largest on-campus basketball arena in the state of Mississippi. The building is the equivalent of seven stories high and is in the shape of an oval 318' long by 268' wide; the outside is marked by regular concrete columns and Mississippi red brick siding, the school seal adorns the front of the building. In 2004, a center hung scoreboard was provided by the Henry Mize Foundation; the scoreboard featured four sides, each with a video screen. It was replaced in 2015 by a similar but updated scoreboard that includes two ring displays along with four main video displays; the current court design was announced in 2016, with the court itself installed in 2017. It features many design details highlighting the school's local ties; the playing area is surrounded by lettering that lists all 82 counties in the state, all appearing in gray except for the school's home of Oktibbeha County, in white lettering at midcourt between the team benches.

Directly above the Oktibbeha County name is a white outline of the state with an "X" marking Starkville's location, the point at which substitutes report to enter the game. The city nickname of "Starkvegas" appears in large all-caps lettering at the baseline in front of the student section. In addition to basketball, the arena is a popular venue for concerts, graduation ceremonies, other events, it was named for George Duke Humphrey, president of Mississippi State from 1934 to 1945. It replaced Mississippi State Gymnasium, built in 1950 and has since been converted to an indoor tennis center. List of NCAA Division I basketball arenas Arena page at the school website Arena page at