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SUMMARY / RELATED TOPICS

Knowledge representation and reasoning

Knowledge representation and reasoning is the field of artificial intelligence dedicated to representing information about the world in a form that a computer system can utilize to solve complex tasks such as diagnosing a medical condition or having a dialog in a natural language. Knowledge representation incorporates findings from psychology about how humans solve problems and represent knowledge in order to design formalisms that will make complex systems easier to design and build. Knowledge representation and reasoning incorporates findings from logic to automate various kinds of reasoning, such as the application of rules or the relations of sets and subsets. Examples of knowledge representation formalisms include semantic nets, systems architecture, frames and ontologies. Examples of automated reasoning engines include inference engines, theorem provers, classifiers; the KR conference series was established to share ideas and progress on this challenging field. The earliest work in computerized knowledge representation was focused on general problem solvers such as the General Problem Solver system developed by Allen Newell and Herbert A. Simon in 1959.

These systems featured data structures for decomposition. The system would begin with a goal, it would decompose that goal into sub-goals and set out to construct strategies that could accomplish each subgoal. In these early days of AI, general search algorithms such as A* were developed. However, the amorphous problem definitions for systems such as GPS meant that they worked only for constrained toy domains. In order to tackle non-toy problems, AI researchers such as Ed Feigenbaum and Frederick Hayes-Roth realized that it was necessary to focus systems on more constrained problems; these efforts led to the cognitive revolution in psychology and to the phase of AI focused on knowledge representation that resulted in expert systems in the 1970s and 80s, production systems, frame languages, etc. Rather than general problem solvers, AI changed its focus to expert systems that could match human competence on a specific task, such as medical diagnosis. Expert systems gave us the terminology still in use today where AI systems are divided into a Knowledge Base with facts about the world and rules and an inference engine that applies the rules to the knowledge base in order to answer questions and solve problems.

In these early systems the knowledge base tended to be a flat structure assertions about the values of variables used by the rules. In addition to expert systems, other researchers developed the concept of frame-based languages in the mid-1980s. A frame is similar to an object class: It is an abstract description of a category describing things in the world and potential solutions. Frames were used on systems geared toward human interaction, e.g. understanding natural language and the social settings in which various default expectations such as ordering food in a restaurant narrow the search space and allow the system to choose appropriate responses to dynamic situations. It was not long before the frame communities and the rule-based researchers realized that there was synergy between their approaches. Frames were good for representing the real world, described as classes, slots with various constraints on possible values. Rules were good for representing and utilizing complex logic such as the process to make a medical diagnosis.

Integrated systems were developed that combined Rules. One of the most powerful and well known was the 1983 Knowledge Engineering Environment from Intellicorp. KEE had a complete rule engine with backward chaining, it had a complete frame based knowledge base with triggers, slots and message passing. Although message passing originated in the object-oriented community rather than AI it was embraced by AI researchers as well in environments such as KEE and in the operating systems for Lisp machines from Symbolics and Texas Instruments; the integration of Frames and object-oriented programming was driven by commercial ventures such as KEE and Symbolics spun off from various research projects. At the same time as this was occurring, there was another strain of research, less commercially focused and was driven by mathematical logic and automated theorem proving. One of the most influential languages in this research was the KL-ONE language of the mid-'80s. KL-ONE was a frame language that had a rigorous semantics, formal definitions for concepts such as an Is-A relation.

KL-ONE and languages that were influenced by it such as Loom had an automated reasoning engine, based on formal logic rather than on IF-THEN rules. This reasoner is called the classifier. A classifier can analyze a set of declarations and infer new assertions, for example, redefine a class to be a subclass or superclass of some other class that wasn't formally specified. In this way the classifier can function as an inference engine, deducing new facts from an existing knowledge base; the classifier can provide consistency checking on a knowledge base. Another area of knowledge representation research was the problem of common sense reasoning. One of the first realizations learned from trying to make software that can function with human natural language was that humans draw on an extensive foundation of knowledge about the real world that we take for granted but, not at all obvious to an artificial agent. Basic principles of common sense physics, intentions, etc. An example is the frame problem, that in an event driven logic there need to be axio

Frietmuseum

The Frietmuseum is a museum in Bruges, devoted to the history of potatoes and the production of Belgian fries. It describes itself as "the first and only museum dedicated to potato fries"; the museum was founded in 2008 by Eddy Van Belle, who had opened two other museums in Bruges, both based in one building: Choco-Story, dedicated to Belgium's chocolate industry, Lumina Domestica, which houses Van Belle's 6,500-piece collection of lamps. Inspired by the popularity of Choco-Story, Van Belle had researched the possibility of a museum dedicated to fries, was encouraged to open the Frietmuseum after discovering that no similar museum existed elsewhere; the Frietmuseum is located in the Gothic Saaihalle at Vlamingstraat 33. This is one of the oldest buildings in the World Heritage listed historic centre of Bruges and dates back to 1399, with an annexe added shortly afterwards. Throughout the fifteenth century, this building was used as a base for the activities of Genoese merchants. Prior to the museum's opening, it underwent a year and a half of renovation work, including restoration of the façade.

During this work, no structural changes were made to the interior of the building. The museum is spread across three floors. Exhibits on the ground floor trace the history of potatoes, beginning in Peru c.8000BC. The first floor details the history of fries, their origins in Belgium; the basement of the building houses a cafe. Exhibits include photographs, historical potato peelers and chip-making machines, a video outlining how to make perfect fries; the building is housed in the Gothic Saaihalle. The building dates back to 1399, was extended as the residence of the Consul of Genoa in 1441, used by weavers from 1578-1750, has since served variously as an inn, café, cinema and since 1978 as a bank and exhibition space. National Heritage Site Official website

Wembley Lions (speedway)

The Wembley Lions were a motorcycle speedway team which operated from 1929 until their closure in 1971. Their track was located at Wembley Park, London; the original stadium which hosted speedway has been redeveloped. After opening in 1929, the Lions joined the Southern League, winning it in 1930 and 1931; the 1932 season saw them join the National League. The Lions continued to compete in the National League until the outbreak of World War II. After the war Wembley continued in the National League, winning the title in the opening season in 1946; the following season they retained their title. The Lions operated until the end of the 1956 season, winning the title a further five times but in 1957 they withdrew from the league before the season started due to the death of Sir Arthur Elvin, the chairman of Wembley Stadium. Many of the Wembley "home" meetings in 1948 were staged at Wimbledon as the Empire Stadium was used for the 1948 Summer Olympics. During this era, speedway went through the biggest crowd "boom" in its history.

Wembley, who ran league meetings every Thursday, had by far the biggest crowds. The average weekly attendances were around the 60,000 mark from 1946-1951, with one meeting of note, a London Cup match between Wembley and West Ham, drawing an estimated crowd of 85,000 with 20,000 locked outside, listening to a BBC radio commentary of the match via loudspeakers set up in the car park. Towards the mid-1950s speedway crowds fell away and Wembley's last season in 1956 saw average attendances of around the 15,000 mark. In 1970, Wembley speedway returned. Promoters Trevor Redmond and Bernard Cottrell bought their licence and the contracts of some of the riders from the Edinburgh Monarchs promoter Ian Hoskins, operating at Coatbridge; the Lions only managed to stay in operation for two seasons due to the stadium not being able to support speedway at all times due to commitments to other events being held there. Wembley staged the Speedway World Championship Final continuously from 1936 to 1938 and when it was re-introduced after World War II from 1949 to 1960.

It went on to stage the championship a further nine times before the last contest at Wembley in 1981. Lions riders won in 1936, 1949, 1950 and 1953. Wembley hosted the British Riders' Championships Finals 1946 to 1948

Snoopy and the Red Baron (video game)

Snoopy and the Red Baron is an Atari 2600 shoot'em up featuring Peanuts character Snoopy and his aviation rival, the Red Baron. It was published by Atari, Inc. in 1983. Snoopy and the Red Baron is a single-player game with the player guiding Snoopy on his doghouse with four variations of difficulty to play; the objective is to shoot down Snoopy's rival, the Red Baron, controls being the stick to maneuver Snoopy and the button to fire. The game starts out with the player having four doghouses, otherwise known as lives, it takes eight hits to destroy the Red Baron, eight hits from the Red Baron to have the player lose a doghouse. An alternative notion is to collect "treats" the Red Baron drops while falling, to avoid skulls and crossbones. Touching the skulls and crossbones or being shot down will undo the player's progress in collecting treats. If the player collects all of the treats and downs all of the Red Barons, bonus points are rewarded. A Gold Baron is earned. In the game, the Red Baron flies above the clouds.

An exclamation mark appears. Snoopy and the Red Baron was released in 1983; this game play-tested better than the Atari 2600 game Bugs Bunny, therefore Bugs Bunny was shelved, allowing Snoopy and the Red Baron to enter the market. The game was released with a Children's Computer Workshop cartridge label, used on few games for the Atari 2600. Snoopy and the Red Baron was the only released game in Atari, Inc.'s Peanuts series, having a planned but unreleased game titled Good Luck, Charlie Brown

Keith Sutton

Keith George Sutton was a British artist and critic Keith Sutton was born in Dulwich on 29 May 1924, the younger son of George William Sutton and Audrey Pearl Dewar. He was educated at Rutlish School, leaving at age 16 to attend Wimbledon School of Art. Called up into the RNVR in July 1943, he served until January 1947 as acting sub-lieutenant. On release he returned to Wimbledon until he won the Alfred Rich scholarship to the Slade School in 1948. Fellow students in his year included Martin Froy and Peter Snow, while he formed particular friendships with entrants the following year including Victor Willing and Michael Andrews and Paula Rego, he was awarded the Tonks prize for drawing, gained his Diploma in 1951 and stayed on for an extra year. In the 1950s there were few openings for young artists apart from teaching and Sutton took up several such opportunities during the next few years while always continuing to paint and draw, he would sometimes stay with Victor Willing and his first wife Hazel at Shalford, near Guildford and there are landscapes and drawings from there.

By 1955 he was writing art criticism for Art News and Review and this continued until 1957. In February–March 1958 he had his first one-man show at the Galerie de Seine in West Halkin Street, he showed twenty four paintings dating from the previous three or four years as well as a portfolio of drawings. There were some sales though several paintings remain to the estate. In 1959 he carried out a commission for two glass mosaic murals for the A. E. I. Research Laboratories at Harlow. At the end of the fifties Sutton was living in University Mansions and for a while in the house of Ronald Alley, the art historian, in Deodar Road. Here he produced his first efforts at collage. In 1963 he moved back to central London into a flat in Winchester Road, Swiss Cottage, remaining there until 1967, he continued to write art criticism during the first half of the sixties: for The New Statesman. He wrote several introductions in catalogues of artists' exhibitions: the sculptor George Fullard, his monograph on Picasso was published in 1962.

In 1965 he was put in charge of the arts section of the newly launched magazine London Life, continuing until it ceased publication two years later. He continued with teaching, now at the Bath Academy, Corsham Court. In 1960 he had stayed with Victor Willing and Paula Rego in Portugal and he felt that the new experiences of sea and landscape infused the smaller still lifes among the paint and collage works on which he now embarked. Influential were his new friendships with the American artists Paul Jenkins and Alice Baber, the young Thomas Erma, he took lengthy working stays in Paris in their company in 1961-2, producing there many of the 22 collages which he was to show at the Hanover Gallery in September 1962. Among the most successful of the works were the tondos inspired by the artist's admiration of the Botticelli tondo The Adoration of the Kings in the National Gallery. Sutton had formed a close friendship with Tom Erma and was devastated when he heard of his never-fully-explained death from gunshot wounds in Paris in 1964, aged only 25.

In 1967 his life was further disrupted as the house in Winchester Road was due for demolition to allow the construction of the Swiss Cottage library and swimming baths. He removed to another flat not far away in Belsize Avenue where he was to remain for the next twenty years or so. In 1966 he had started teaching part-time at Stourbridge College of Art and he stayed on there until 1972. While there he continued to create collages, in a developing and less hard edge style, but started on so-called'motif' paintings in acrylics. Decorative, these were of stylised vases of flowers or other still life subjects; this period was his happiest and most fulfilling as he was writing and teaching. However, in 1972 he had to relinquish his position at Stourbridge on its being made a full-time post, he did not feel able to move there permanently to abandon his ageing parents, now living in Cranleigh, Surrey. As a consequence for the next few years he fell on rather hard times financially but he nonetheless continued to paint.

He had a circle of friends, of whom he saw a good deal, which allowed of holiday breaks in North Wales and Suffolk. The paintings of this period were nearly all inspired by something he had seen, sometimes an optical effect. In 1975 and 1979 first his father and his mother died. Once family affairs were settled Sutton found himself in a state of financial independence and greater freedom. In the first few years of the eighties he started painting again with enthusiasm, producing some eight or ten paintings which might well be his best work. Concurrently and subsequently he worked in gouache or watercolour on paper to produce a series of more than twenty brilliantly coloured small abstracts, sometimes titled not. Sadly, fresh worries came along by 1983, his landlord, who had bought the house and was now living in it, sought to evict him. After litigation, in 1986 Sutton had to move to the much smaller flat, offered him in Gloucester Avenue. Painful decisions had to be made as to the disposal of paintings and furniture.

The episode was traumatic. The death, in 1988, of Victor Willing, his friend since Slade days, was a further blow and he succumbed to depression and a series of ischaemic attacks, he died on 26 July 1991 in University

VDAC1

Voltage-dependent anion-selective channel 1 is a beta barrel protein that in humans is encoded by the VDAC1 gene located on chromosome 5. It forms an ion channel in the outer mitochondrial membrane and the outer cell membrane. In the OMM, it allows ATP to diffuse out of the mitochondria into the cytoplasm. In the cell membrane, it is involved in volume regulation. Within all eukaryotic cells, mitochondria are responsible for synthesis of ATP among other metabolite needed for cell survival. VDAC1 therefore allows for communication between the mitochondrion and the cell mediating the balance between cell metabolism and cell death. Besides metabolic permeation, VDAC1 acts as a scaffold for proteins such as hexokinase that can in turn regulate metabolism; this protein is a voltage-dependent anion channel and shares high structural homology with the other VDAC isoforms, which are involved in the regulation of cell metabolism, mitochondrial apoptosis, spermatogenesis. Over expression and misregulation of this pore could lead to apoptosis in the cell leading to a variety of diseases within the body.

In particular, since VDAC1 is the major calcium ion transport channel, its dysfunction is implicated in cancer, Parkinson's, Alzheimer's disease. In addition, recent studies have shown that an over expression within the VDAC1 protein is linked to Type 2 Diabetes. Lund University released a study that demonstrated the effects of blocking VDAC1 over expression can prevent the spread of Type 2 Diabetes; the three VDAC isoforms have conserved DNA sequences as well as 3D structures forming a wide β-barrel structure, inside of which the alpha helical N-terminal segment resides to close the pore. VDAC1's structure was solved by 3 independent labs by x-ray crystallography, Nuclear Magnetic Resonance spectroscopy, or a combination of both. Two of these structural studies were used to determine human VDAC1 structure while X-ray crystallography was used to solve murine VDAC1 structure that differs from hVDAC1 by only two residues; these determined structures aligned with earlier circular dichorism studies that predicted the presence of alpha helix and β-strand domains.

Structural analysis of mVDAC1's structure showed a barrel-like channel composed of 19 amphipathic β-strands, with the N-terminus and C-terminus both facing towards the inter membrane space of the mitochondrion. Β-strands are connected via loops and are arranged in an anti-parallel pattern with the exception of β-strands 1 and 19 which are parallel. The pore has a height of 40 Ẳ, spans a distance of 27 Ẳ by 20 Ẳ at the openings and tapers down to 20 Ẳ by 14 Ẳ at the N-terminal α-helix segment in the open state; the closed state conformation has yet to be determined. Additionally, the N-terminus has an alpha helical segment, held to the inside wall of the pore by hydrophobic interactions with residues on β-sheets 8-18; this N-terminus can serve as a scaffold for the movement of ions or attachment of proteins. One such example is seen. A significant residue to point out is the glutamate located at the 73rd residue on the amino acid chain; this residue is found in VDAC1 and VDAC2 but not VDAC3. The side chain of this charged residue points into the phospholipid bilayer which would cause repulsive forces to occur.

E73 however, has been implicated in VDAC1 function and interaction. VDAC1 belongs to the mitochondrial porin family and is expected to share similar biological functions to the other VDAC isoforms. Of the three isoforms, VDAC1 is the main calcium ion transport channel and the most abundantly transcribed. VDAC1 is involved in cell metabolism by transporting ATP and other small metabolites across the outer mitochondrial membrane allowing regulation of the TCA cycle and, by extension, reactive oxygen species production. In yeast cells, ROS accumulates in response to oxidative stress, which results in impaired mitochondrial function and a “petite” phenotype. However, petite yeast cells exhibit a longer lifespan than wild-type cells and indicate a protective function by VDAC1 in similar circumstances, such as aging. VDAC1 allows for the conductance of molecules out of the mitochondrion, its permeability is dependent on VDAC1's conformational state, determined by voltage. At low voltage, the pore is in an "open" state where the channel is weakly anion selective and allows for a greater flux of metabolites.

Because of the large pore size, metabolic gating under saturated ATP conditions reveal a transport of 2,000,000 ATP/second and a transport of 10,000 ATP under physiological conditions. At a higher voltage in the positive or negative direction, the pore is in a "closed" state and is weakly cation selective allowing for less metabolites to be transported; the flux of metabolites can be seen as negligible. This change in states is mediated by a conformational change in the protein that has yet to be discovered. Since the alpha helical N-terminus segment is located in the center of the pore, it is ideally situated for metabolic gating; this lead researchers to believe that the Alpha helix was a key contributor to determining the conformational states. However, more recent studies have shown the N-terminal is unnecessary for proper voltage gating and therefore suggest the flexible beta barrel as the mechanism of conformational change. Atomic Force Microscopy revealed the presence of VDAC1 monomers as well as dimers and larger oligomers showcasing the interaction of the pore with itself, dimers are more frequent.

HVDAC1 in particular has been shown to arrange in parallel dimers leading to increased permeability of the pore. The glutamate located at the 73rd position on VDAC1 has been shown