Software development process
In software engineering, a software development process is the process of dividing software development work into distinct phases to improve design, product management, project management. It is known as a software development life cycle; the methodology may include the pre-definition of specific deliverables and artifacts that are created and completed by a project team to develop or maintain an application. Most modern development processes can be vaguely described as agile. Other methodologies include waterfall, prototyping and incremental development, spiral development, rapid application development, extreme programming; some people consider a life-cycle "model" a more general term for a category of methodologies and a software development "process" a more specific term to refer to a specific process chosen by a specific organization. For example, there are many specific software development processes that fit the spiral life-cycle model; the field is considered a subset of the systems development life cycle.
The software development methodology framework didn't emerge until the 1960s. According to Elliott the systems development life cycle can be considered to be the oldest formalized methodology framework for building information systems; the main idea of the SDLC has been "to pursue the development of information systems in a deliberate and methodical way, requiring each stage of the life cycle––from inception of the idea to delivery of the final system––to be carried out rigidly and sequentially" within the context of the framework being applied. The main target of this methodology framework in the 1960s was "to develop large scale functional business systems in an age of large scale business conglomerates. Information systems activities revolved around heavy data processing and number crunching routines". Methodologies and frameworks range from specific proscriptive steps that can be used directly by an organization in day-to-day work, to flexible frameworks that an organization uses to generate a custom set of steps tailored to the needs of a specific project or group.
In some cases a "sponsor" or "maintenance" organization distributes an official set of documents that describe the process. Specific examples include: 1970sStructured programming since 1969 Cap Gemini SDM from PANDATA, the first English translation was published in 1974. SDM stands for System Development Methodology1980sStructured systems analysis and design method from 1980 onwards Information Requirement Analysis/Soft systems methodology1990sObject-oriented programming developed in the early 1960s, became a dominant programming approach during the mid-1990s Rapid application development, since 1991 Dynamic systems development method, since 1994 Scrum, since 1995 Team software process, since 1998 Rational Unified Process, maintained by IBM since 1998 Extreme programming, since 19992000sAgile Unified Process maintained since 2005 by Scott Ambler Disciplined agile delivery Supersedes AUP2010s Scaled Agile Framework Large-Scale Scrum DevOpsIt is notable that since DSDM in 1994, all of the methodologies on the above list except RUP have been agile methodologies - yet many organisations governments, still use pre-agile processes.
Software process and software quality are interrelated. Among these another software development process has been established in open source; the adoption of these best practices known and established processes within the confines of a company is called inner source. Several software development approaches have been used since the origin of information technology, in two main categories. An approach or a combination of approaches is chosen by management or a development team. "Traditional" methodologies such as waterfall that have distinct phases are sometimes known as software development life cycle methodologies, though this term could be used more to refer to any methodology. A "life cycle" approach with distinct phases is in contrast to Agile approaches which define a process of iteration, but where design and deployment of different pieces can occur simultaneously. Continuous integration is the practice of merging all developer working copies to a shared mainline several times a day. Grady Booch first named and proposed CI in his 1991 method, although he did not advocate integrating several times a day.
Extreme programming adopted the concept of CI and did advocate integrating more than once per day – as many as tens of times per day. Software prototyping is about creating prototypes, i.e. incomplete versions of the software program being developed. The basic principles are: Prototyping is not a standalone, complete development methodology, but rather an approach to try out particular features in the context of a full methodology. Attempts to reduce inherent project risk by breaking a project into smaller segments and providing more ease-of-change during the development process; the client is involved throughout the development process, which increases the likelihood of client acceptance of the final implementation. While some prototypes are developed with the expectation that they will be discarded, it is possible in some cases to evolve from prototype to working system. A basic understanding of the fundamental business problem is necessary to avoid solving the wrong problems, but this is true for all software methodologies.
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Richard Phillips Feynman was an American theoretical physicist, known for his work in the path integral formulation of quantum mechanics, the theory of quantum electrodynamics, the physics of the superfluidity of supercooled liquid helium, as well as in particle physics for which he proposed the parton model. For his contributions to the development of quantum electrodynamics, jointly with Julian Schwinger and Shin'ichirō Tomonaga, received the Nobel Prize in Physics in 1965. Feynman developed a used pictorial representation scheme for the mathematical expressions describing the behavior of subatomic particles, which became known as Feynman diagrams. During his lifetime, Feynman became one of the best-known scientists in the world. In a 1999 poll of 130 leading physicists worldwide by the British journal Physics World he was ranked as one of the ten greatest physicists of all time, he assisted in the development of the atomic bomb during World War II and became known to a wide public in the 1980s as a member of the Rogers Commission, the panel that investigated the Space Shuttle Challenger disaster.
Along with his work in theoretical physics, Feynman has been credited with pioneering the field of quantum computing and introducing the concept of nanotechnology. He held the Richard C. Tolman professorship in theoretical physics at the California Institute of Technology. Feynman was a keen popularizer of physics through both books and lectures including a 1959 talk on top-down nanotechnology called There's Plenty of Room at the Bottom and the three-volume publication of his undergraduate lectures, The Feynman Lectures on Physics. Feynman became known through his semi-autobiographical books Surely You're Joking, Mr. Feynman! and What Do You Care What Other People Think? and books written about him such as Tuva or Bust! by Ralph Leighton and the biography Genius: The Life and Science of Richard Feynman by James Gleick. Feynman was born on May 11, 1918, in Queens, New York City, to Lucille née Phillips, a homemaker, Melville Arthur Feynman, a sales manager from Minsk in Belarus. Both were Lithuanian Jews.
Feynman was a late talker, did not speak until after his third birthday. As an adult he spoke with a New York accent strong enough to be perceived as an affectation or exaggeration—so much so that his friends Wolfgang Pauli and Hans Bethe once commented that Feynman spoke like a "bum"; the young Feynman was influenced by his father, who encouraged him to ask questions to challenge orthodox thinking, and, always ready to teach Feynman something new. From his mother, he gained the sense of humor; as a child, he had a talent for engineering, maintained an experimental laboratory in his home, delighted in repairing radios. When he was in grade school, he created a home burglar alarm system while his parents were out for the day running errands; when Richard was five his mother gave birth to a younger brother, Henry Phillips, who died at age four weeks. Four years Richard's sister Joan was born and the family moved to Far Rockaway, Queens. Though separated by nine years and Richard were close, they both shared a curiosity about the world.
Though their mother thought women lacked the capacity to understand such things, Richard encouraged Joan's interest in astronomy, Joan became an astrophysicist. Feynman's parents were not religious, by his youth, Feynman described himself as an "avowed atheist". Many years in a letter to Tina Levitan, declining a request for information for her book on Jewish Nobel Prize winners, he stated, "To select, for approbation the peculiar elements that come from some Jewish heredity is to open the door to all kinds of nonsense on racial theory", adding, "at thirteen I was not only converted to other religious views, but I stopped believing that the Jewish people are in any way'the chosen people'". In his life, during a visit to the Jewish Theological Seminary, he encountered the Talmud for the first time and remarked that it contained a medieval kind of reasoning and was a wonderful book. Feynman attended Far Rockaway High School, a school in Far Rockaway, attended by fellow Nobel laureates Burton Richter and Baruch Samuel Blumberg.
Upon starting high school, Feynman was promoted into a higher math class. A high-school-administered IQ test estimated his IQ at 125—high, but "merely respectable" according to biographer James Gleick, his sister Joan did better. Years he declined to join Mensa International, saying that his IQ was too low. Physicist Steve Hsu stated of the test: I suspect that this test emphasized verbal, as opposed to mathematical, ability. Feynman received the highest score in the United States by a large margin on the notoriously difficult Putnam mathematics competition exam... He had the highest scores on record on the math/physics graduate admission exams at Princeton... Feynman's cognitive abilities might have been a bit lopsided... I recall looking at excerpts from a notebook Feynman kept while an undergraduate... contained a number of misspellings and grammatical errors. I doubt Feynman cared much about such things; when Feynman was 15, he taught himself trigonometry, advanced algebra, infinite series, analytic geometry, both differential and integral calculus.
Before entering college, he was experimenting with and deriving mathematical topics such as the half-derivative using his own notation. He created special symbols for logarithm, sine and tangent functions so they did not look like three variables multiplied together, for the derivative, to remove the temptation of canceling out the d's. A member
Computer programming is the process of designing and building an executable computer program for accomplishing a specific computing task. Programming involves tasks such as: analysis, generating algorithms, profiling algorithms' accuracy and resource consumption, the implementation of algorithms in a chosen programming language; the source code of a program is written in one or more languages that are intelligible to programmers, rather than machine code, directly executed by the central processing unit. The purpose of programming is to find a sequence of instructions that will automate the performance of a task on a computer for solving a given problem; the process of programming thus requires expertise in several different subjects, including knowledge of the application domain, specialized algorithms, formal logic. Tasks accompanying and related to programming include: testing, source code maintenance, implementation of build systems, management of derived artifacts, such as the machine code of computer programs.
These might be considered part of the programming process, but the term software development is used for this larger process with the term programming, implementation, or coding reserved for the actual writing of code. Software engineering combines engineering techniques with software development practices. Reverse engineering is the opposite process. A hacker is any skilled computer expert that uses their technical knowledge to overcome a problem, but it can mean a security hacker in common language. Programmable devices have existed at least as far back as 1206 AD, when the automata of Al-Jazari were programmable, via pegs and cams, to play various rhythms and drum patterns. However, the first computer program is dated to 1843, when mathematician Ada Lovelace published an algorithm to calculate a sequence of Bernoulli numbers, intended to be carried out by Charles Babbage's Analytical Engine. Women would continue to dominate the field of computer programming until the mid 1960s. In the 1880s Herman Hollerith invented the concept of storing data in machine-readable form.
A control panel added to his 1906 Type I Tabulator allowed it to be programmed for different jobs, by the late 1940s, unit record equipment such as the IBM 602 and IBM 604, were programmed by control panels in a similar way. However, with the concept of the stored-program computers introduced in 1949, both programs and data were stored and manipulated in the same way in computer memory. Machine code was the language of early programs, written in the instruction set of the particular machine in binary notation. Assembly languages were soon developed that let the programmer specify instruction in a text format, with abbreviations for each operation code and meaningful names for specifying addresses. However, because an assembly language is little more than a different notation for a machine language, any two machines with different instruction sets have different assembly languages. Kathleen Booth created one of the first Assembly languages in 1950 for various computers at Birkbeck College. High-level languages allow the programmer to write programs in terms that are syntactically richer, more capable of abstracting the code, making it targetable to varying machine instruction sets via compilation declarations and heuristics.
The first compiler for a programming language was developed by Grace Hopper. When Hopper went to work on UNIVAC in 1949, she brought the idea of using compilers with her. Compilers harness the power of computers to make programming easier by allowing programmers to specify calculations by entering a formula using infix notation for example. FORTRAN, the first used high-level language to have a functional implementation which permitted the abstraction of reusable blocks of code, came out in 1957. In 1951 Frances E. Holberton developed the first sort-merge generator which ran on the UNIVAC I. Another woman working at UNIVAC, Adele Mildred Koss, developed a program, a precursor to report generators. In USSR, Kateryna Yushchenko developed the Address programming language for the MESM in 1955; the idea for the creation of COBOL started in 1959 when Mary K. Hawes, who worked for Burroughs Corporation, set up a meeting to discuss creating a common business language, she invited six people, including Grace Hopper.
Hopper was involved in developing COBOL as a business language and creating "self-documenting" programming. Hopper's contribution to COBOL was based on her programming language, called FLOW-MATIC. In 1961, Jean E. Sammet developed FORMAC and published Programming Languages: History and Fundamentals which went on to be a standard work on programming languages. Programs were still entered using punched cards or paper tape. See computer programming in the punch card era. By the late 1960s, data storage devices and computer terminals became inexpensive enough that programs could be created by typing directly into the computers. Frances Holberton created a code to allow keyboard inputs while she worked at UNIVAC. Text editors were developed that allowed changes and corrections to be made much more than with punched cards. Sister Mary Kenneth Keller worked on developing the programming language, BASIC when she was a graduate student at Dartmouth in the 1960s. One of the first object-oriented programming languages, was developed by seven programmers, including Adele Goldberg, in the 1970s.
In 1985, Radia Perlman developed the Spannin
Tanna is an island in Tafea Province of Vanuatu. It is 19 kilometres wide, with a total area of 550 square kilometres, its highest point is the 1,084-metre summit of Mount Tukosmera in the south of the island. Siwi Lake was located in the east, northeast of the peak, close to the coast until mid April 2000 when following unusually heavy rain, the lake burst down the valley into Sulphur Bay, destroying the village with no loss of life. Mount Yasur is an accessible active volcano, located on the southeast coast. Tanna was first settled about 400 BC by Melanesians from the surrounding islands; the glowing light of Mount Yasur attracted James Cook, the first European to visit the island, in August 1774, where he landed in an inlet on the southeastern tip of the island that he named Port Resolution after his ship HMS Resolution. He gave the island the name of Tanna from the local name for earth, tana in the Kwamera language. In the 19th century and missionaries arrived; the Tannese stuck to their traditions more than other islands.
Tanna was not a principal site of World War II, but about 1,000 people from Tanna were recruited to work on the American military base on Éfaté. Exposure to First World living standards may have led to the development of cargo cults. Many have died out, but the John Frum cult remains strong on Tanna today at Sulphur Bay in the south east and Green Point in the South West of the Island. A recent documentary Waiting for John by Jessica Sherry provides a history and overview of the current scene regarding these beliefs. A secessionist movement began in the 1970s, the Nation of Tanna was proclaimed on 24 March 1974. While the British were more open to allowing its holdings in Vanuatu to achieve independence, it was opposed by the French colonists and suppressed by the Anglo-French Condominium authorities on June 29, 1974. In 1980, there was another attempt to secede, declaring the Tafea Nation on 1 January 1980, its name coming from the initials of the five islands that were to be part of the nation.
British forces intervened on 26 May 1980, allowing the island to become part of the newly independent nation of Vanuatu on 30 July 1980. Tanna and nearby Erromango were devastated by cyclone Pam in mid-March 2015, with reports of an unknown number of deaths, complete destruction of the island’s infrastructure and permanent shelters, no drinking water. Following this, an El Niño-spurred drought further impacted on the people of Tanna, it is the most populous island in Tafea Province, with a population of about 29,000, one of the most populous islands in the country. Isangel, the provincial administrative capital, is on the west coast near the island's largest town of Lénakel. Tanna is populated entirely by Melanesians and they follow a more traditional lifestyle than many other islands; some of the higher altitude villages are known as kastom villages, where modern inventions are restricted, the inhabitants wear penis sheaths and grass skirts, the children do not go to public schools. According to anthropologist Joël Bonnemaison, author of "The Tree and the Canoe: history and ethnography of Tanna," their resistance to change is due to their traditional worldview and how they "perceive and account for the dual concepts of space and time."
The island is the centre of the John Frum religious movement, which attracts tourist interest as a cargo cult. The first John appeared at night as a spirit at a place called Green Point and told the people to return to their traditional way of life, or kastom. From that time kastom on Tanna has been seen as an alternative to the modernity encouraged by many missionary denominations. Yaohnanen is the centre of the Prince Philip Movement, which reveres Prince Philip, Duke of Edinburgh, the prince consort of the United Kingdom; the cult is examined by British writer Matthew Baylis in his 2013 book Man Belong Mrs Queen: Adventures with the Philip Worshippers. Christian missionary John Gibson Paton served in Tanna in the mid 1800s. Cannibalism was practiced. In the biography of Paton the horror of the pagan practice of abusing and murdering disobedient wives is detailed. There are three main languages spoken on Tanna: the southern language of Kwamera, the South-Western language adjacent to the slopes of Tokosmera, of which there are many dialects spoken by small groupings, constitute two of the languages.
The remaining majority of Tanna islanders speak four dialects, being North Tanna in the northwest, Lénakel in the west-central area near Lénakel, the middle bush dialect in the central plateau of the island, close to Lenakel Whitesands in the northeast near Whitesands. These are grouped into the Tanna languages family, a subgroup of the South Vanuatu languages, an Austronesian language branch. According to Ethnologue, each is spoken by a few thousand, Lénakel, with 8,000 speakers, is one of the dialects of Vanuatu with the most speakers. Many people on Tanna speak Bislama, one of Vanuatu's three official languages; the island is one of the most fertile in Vanuatu and produces kava, coconut and other fruits and vegetables. Tourism has become more important, as tourists are attracted to the volcano and traditional culture. To help preserve the integrity of culture as a tourism asset, only local people are permitted to act as guides. There are various types of accommodation on the island. Five men from Tanna's Prince Philip Movement car
A cargo cult is a belief system among members of a undeveloped society in which adherents practice superstitious rituals hoping to bring modern goods supplied by a more technologically advanced society. These cults, millenarian in nature, were first described in Melanesia in the wake of contact with advanced Western cultures; the name derives from the belief which began among Melanesians in the late 19th and early 20th centuries that various ritualistic acts such as the building of an airplane runway will result in the appearance of material wealth highly desirable Western goods, via Western airplanes. Cargo cults develop during a combination of crises. Under conditions of social stress, such a movement may form under the leadership of a charismatic figure; this leader may have a "vision" of the future linked to an ancestral efficacy thought to be recoverable by a return to traditional morality. This leader may characterize the present state as a dismantling of the old social order, meaning that social hierarchy and ego boundaries have been broken down.
Contact with colonizing groups brought about a considerable transformation in the way indigenous peoples of Melanesia have thought about other societies. Early theories of cargo cults began from the assumption that practitioners failed to understand technology, colonization, or capitalist reform. However, many of these practitioners focus on the importance of sustaining and creating new social relationships, with material relations being secondary. Since the late twentieth century, alternative theories have arisen. For example, some scholars, such as Kaplan and Lindstrom, focus on Europeans' characterization of these movements as a fascination with manufactured goods and what such a focus says about Western commodity fetishism. Others point to the need to see each movement as reflecting a particularized historical context eschewing the term "cargo cult" for them unless there is an attempt to elicit an exchange relationship from Europeans. Cargo cults are marked by a number of common characteristics, including a "myth-dream", a synthesis of indigenous and foreign elements.
The indigenous societies of Melanesia were characterized by a "big man" political system in which individuals gained prestige through gift exchanges. The more wealth a man could distribute, the more people in his debt, the greater his renown; those who were unable to reciprocate were identified as "rubbish men". Faced, through colonialism, with foreigners with a unending supply of goods for exchange, indigenous Melanesians experienced "value dominance"; that is, they were dominated by others in terms of their own value system. Since the modern manufacturing process is unknown to them, members and prophets of the cults maintain that the manufactured goods of the non-native culture have been created by spiritual means, such as through their deities and ancestors; these goods are intended for the local indigenous people, but the foreigners have unfairly gained control of these objects through malice or mistake. Thus, a characteristic feature of cargo cults is the belief that spiritual agents will, at some future time, give much valuable cargo and desirable manufactured products to the cult members.
Symbols associated with Christianity and modern Western society tend to be incorporated into their rituals. Notable examples of cargo cult activity include the setting up of mock airstrips, airplanes and dining rooms, as well as the fetishization and attempted construction of Western goods, such as radios made of coconuts and straw. Believers may stage "drills" and "marches" with sticks for rifles and use military-style insignia and national insignia painted on their bodies to make them look like soldiers, thereby treating the activities of Western military personnel as rituals to be performed for the purpose of attracting the cargo; the term cargo cult was first used in print in 1945 by Norris Mervyn Bird, repeating a derogatory description used by planters and businessmen in the Australian Territory of Papua. The term was adopted by anthropologists, applied retroactively to movements in a much earlier era.1964 Peter Lawrence: "cargo ritual was any religious activity designed to produce goods in this way and assume to have been taught... by the deity" Discussions of cargo cults begin with a series of movements that occurred in the late nineteenth century and early twentieth century.
The earliest recorded cargo cult was the Tuka Movement that began in Fiji in 1885 at the height of British colonial plantation era. The movement began with a promised return to a golden age of ancestral potency. Minor alterations to priestly practices were undertaken to update them and attempt to recover some kind of ancestral efficacy. Colonial authorities saw Tuka as a rebel, he was exiled, although he kept returning. Cargo cults occurred periodically in many parts of the island of New Guinea, including the Taro Cult in northern Papua New Guinea and the Vailala Madness that arose from 1919 to 1922; the last was documented by Francis Edgar Williams, one of the first anthropologists to conduct fieldwork in Papua New Guinea. Less dramatic cargo cults have appeared in western New Guinea as well, including the Asmat and Dani areas; the most known period of cargo cult activity occurred among the M