In computing, a virtual machine is an emulation of a computer system. Virtual machines are based on computer architectures and provide functionality of a physical computer, their implementations may involve software, or a combination. There are different kinds of virtual machines, each with different functions: System virtual machines provide a substitute for a real machine, they provide functionality needed to execute entire operating systems. A hypervisor uses native execution to share and manage hardware, allowing for multiple environments which are isolated from one another, yet exist on the same physical machine. Modern hypervisors use hardware-assisted virtualization, virtualization-specific hardware from the host CPUs. Process virtual machines are designed to execute computer programs in a platform-independent environment; some virtual machines, such as QEMU, are designed to emulate different architectures and allow execution of software applications and operating systems written for another CPU or architecture.

Operating-system-level virtualization allows the resources of a computer to be partitioned via the kernel. The terms are not universally interchangeable. A "virtual machine" was defined by Popek and Goldberg as "an efficient, isolated duplicate of a real computer machine." Current use includes virtual machines. The physical, "real-world" hardware running the VM is referred to as the'host', the virtual machine emulated on that machine is referred to as the'guest'. A host can emulate several guests, each of which can emulate different operating systems and hardware platforms; the desire to run multiple operating systems was the initial motive for virtual machines, so as to allow time-sharing among several single-tasking operating systems. In some respects, a system virtual machine can be considered a generalization of the concept of virtual memory that preceded it. IBM's CP/CMS, the first systems to allow full virtualization, implemented time sharing by providing each user with a single-user operating system, the Conversational Monitor System.

Unlike virtual memory, a system virtual machine entitled the user to write privileged instructions in their code. This approach had certain advantages, such as adding input/output devices not allowed by the standard system; as technology evolves virtual memory for purposes of virtualization, new systems of memory overcommitment may be applied to manage memory sharing among multiple virtual machines on one computer operating system. It may be possible to share memory pages that have identical contents among multiple virtual machines that run on the same physical machine, what may result in mapping them to the same physical page by a technique termed kernel same-page merging; this is useful for read-only pages, such as those holding code segments, the case for multiple virtual machines running the same or similar software, software libraries, web servers, middleware components, etc. The guest operating systems do not need to be compliant with the host hardware, thus making it possible to run different operating systems on the same computer to support future software.

The use of virtual machines to support separate guest operating systems is popular in regard to embedded systems. A typical use would be to run a real-time operating system with a preferred complex operating system, such as Linux or Windows. Another use would be for novel and unproven software still in the developmental stage, so it runs inside a sandbox. Virtual machines have other advantages for operating system development and may include improved debugging access and faster reboots. Multiple VMs running their own guest operating system are engaged for server consolidation. A process VM, sometimes called an application virtual machine, or Managed Runtime Environment, runs as a normal application inside a host OS and supports a single process, it is created when that process is destroyed when it exits. Its purpose is to provide a platform-independent programming environment that abstracts away details of the underlying hardware or operating system and allows a program to execute in the same way on any platform.

A process VM provides a high-level abstraction – that of a high-level programming language. Process VMs are implemented using an interpreter; this type of VM has become popular with the Java programming language, implemented using the Java virtual machine. Other examples include the. NET Framework, which runs on a VM called the Common Language Runtime. All of them can serve as an abstraction layer for any computer language. A special case of process VMs are systems that abstract over the communication mechanisms of a computer cluster; such a VM does not consist of a single process, but one process per physical machine in the cluster. They are designed to ease the task of programming concurrent applications by letting the programmer focus on algorithms rather than the communication mechanisms provided by the interconnect and the OS, they do not hide the fact that communication takes place, as such do not attempt to present the cluster as a single machine. Unlike other process VMs, these systems do not provide a specific programming language, but are embedded in an existing language.

Examples are Parallel Virtual Machine

Mattie Gunterman, born Ida Madeline Warner, was a Canadian photographer and mining camp cook in British Columbia. Gunterman started taking photos in the spring of 1897 documenting her family and from that point forward her interest and skill in photography continued to grow. From the years 1899 to 1911, she served as a cook at a mining camp while creating autobiographical photographs, she received some formal training about the basics of photography while growing up in La Crosse from her photographer uncle. Gunterman included herself in her photographs creating a personal narrative of pioneer life in Canada and representing herself as a self-sufficient and confident leader, she contributed a notable historical record of the early 1900s mining boom in Lardeau, a former mining region located in the Kootenays region of British Columbia. In 1927, the Gunterman's home in Beaton was destroyed by a fire; the only existing work of Gunterman's are three photograph albums that belong to her grandson, Avery Gunterman and three hundred glass plate negatives that are part of the Vancouver Public Library collection.

An exhibition of her work alongside Emily Carr’s was on display at the Vancouver Art Gallery from May 5 to September 3, 2018. Mattie Gunterman was born in La Crosse and not much is known about her family or childhood. An 1880 United States census provides confirmation that she lived with her grandmother and that her mother was born in Pennsylvania and her father was born in Michigan, she continuously battled health problems throughout her life. She learned photography from an uncle. In 1889 she moved west to Seattle, Washington, she married William Gunterman, a candy maker in 1891 and the two had one son together, Henry, in 1892. She had consistent problems with her lungs and her health weakened in 1896. In 1897 the Guntermans trekked to British Columbia to see about moving there permanently and along this trip she took some of her earliest photographs, her health was a major factor that influenced her life and she was advised by her doctor to move to a drier climate. Thus her and her husband decided to permanently move from Seattle to Beaton, British Columbia known as Thomson's Landing in 1898.

Although Gunterman continuously struggled with her health, she had a survivalist attitude and persevered through twelve-hour shifts at the mining cookhouses. Gunterman took photographs from 1897 to 1911, her photographs were taken in areas surrounding Beaton and the Arrow Lakes District of British Columbia as well as in the Pacific Northwest and California during her travels there in 1905. During the winter months Gunterman would develop her glass plate negatives and turn them into prints, her primary purpose for taking photographs was to record her life and surroundings for her son Henry. She created her own autobiographical narrative through her photographs. In order to create self-portraits and to include herself in group photos, Gunterman would use a piece of rubber tubing attached to the camera's inflatable shutter at one end and a rubber bulb at the other to take the picture; the first camera that she used was a Bull's Eye snapshot camera. Her works at the start consisted of posed group photos.

She purchased a No.5 Cartridge Kodak 4 x 5 plate camera in 1898 as it allowed for more versatility when playing with exposure and shutter speed. In 1902 Gunterman became the chef at the Nettie-L mine in the Lardeau region and at each long work shift she brought along her camera, she captured everyday life at the mine such as scenic views of the Lardeau region, men working hard in the mine and her fellow kitchen co-workers. Her photographs expose the gruelling work at the mine but focus on more lighthearted aspects such as games they would play. Mining operations such as the Nettie-L and other surrounding mines ceased by 1905; however within the Kootenays logging activity increased and became another subject for Gunterman to photograph. Her work is essential for understanding life during the mining boom in the early 1900s. Furthermore, her photographs of both mining and logging activity are fundamental for understanding the jobs that drove the Canadian economy during the turn of the century. Gunterman's work is some of the only photographic evidence of these mining towns when they were flourishing.

In present-day these towns do not exist therefore her photographs serve to remember this region when it was prosperous and thriving. During the late 1910s and into the 1920s when Beaton had become a quieter area, along with her husband Will worked as travelling cooks in nearby areas. In 1927, the Guntermans home burned down. However, a number of glass plate negatives and a few albums were stored elsewhere. Gunterman died in 1945 and three of her photograph albums are in the possession of her grandson, Avery Gunterman. Ron D’Altroy of the Vancouver Public Library became interested in Gunterman's work in 1961 and rediscovered three hundred of her glass plate negatives in Henry Gunterman's attic. After collecting these photographs and gaining permission to keep them, the Vancouver Public Library Board digitized her photographs, her photographs help to reveal life in the Kootenays region of British Columbia, which does not exist today. Gunterman's work continues to gain more attention as it has become more accessible to the public through its digitization.

From April 28 to September 3, 2018 her work was displayed alongside Emily Carr's at the Vancouver Art Gallery in an exhibition entitled "Emily Carr in Dialogue with Mattie Gunterman."

The ADCIRC model is a high-performance, cross-platform numerical ocean circulation model popular in simulating storm surge and coastal circulation problems. Developed by Drs. Rick Luettich and Joannes Westerink, the model is developed and maintained by a combination of academic and corporate partners, including the University of North Carolina at Chapel Hill, the University of Notre Dame, the US Army Corps of Engineers; the ADCIRC system includes an independent multi-algorithmic wind forecast model and has advanced coupling capabilities, allowing it to integrate effects from sediment transport, waves, surface runoff, baroclinicity. The model is free, with source code made available by request via the website, allowing users to run the model on any system with a Fortran compiler. A pre-compiled Windows version of the model can be purchased alongside the SMS software. ADCIRC is coded in Fortran, can be used with native binary, text, or netCDF file formats; the model formulation is based on the shallow water equations, solving the continuity equation and the momentum equations.

ADCIRC utilizes the finite element method in either three-dimensional or two-dimensional depth-integrated form on a triangular unstructured grid with Cartesian or spherical coordinates. It can run in either barotropic or baroclinic modes, allowing inclusion of changes in water density and properties such as salinity and temperature. ADCIRC can be run either in serial mode or in parallel on supercomputers via MPI; the model has been optimized to be parallelized, in order to facilitate rapid computation of large, complex problems. ADCIRC is able to apply several different bottom friction formulations including Manning's n-based bottom drag due to changes in land coverage, as well as utilize atmospheric forcing data from several sources, further reduce the strength of the wind forcing due to surface roughness effects; the model is able to incorporate effects such as time-varying topography and bathymetry, boundary fluxes from rivers or other sources, tidal potential, sub-grid scale features like levees.

ADCIRC is coupled to a wind wave model such as STWAVE, SWAN, or WAVEWATCH III in storm surge applications where wave radiation stress can have important effects on ocean circulation and vice versa. In these applications, the model is able to take advantage of tight coupling with wave models to increase calculation accuracy. ADCIRC official website

Jan Harrison is an American painter and sculptor whose work, which features animal imagery, centers on the animal soul and voice as they relate to human existence and the collective psyche. Her art is informed by the philosophy of deep ecology, a monograph detailing her work describes it as “excavat the arcane kingdom of the human psyche, so long tyrannized by the repressive and oppressive forces of socialization." She has exhibited in the United States and abroad, her work is featured in In The Making: Creative Options for Contemporary Art. Harrison speaks and sings in a language of vocables, "Animal Tongues," which she performs with her visual art, she has received six grants in the arts, is the Inaugural Recipient of the Recharge Foundation Fellowship for New Surrealist Art, New York Foundation for the Arts, NYFA, 2019. She lives and works in New York’s Hudson Valley. Arcana Mundi: Selected Works 1979-2000, Jan Harrison and Linda Weintraub, Ltd. “Internal Sources of Inspiration: Soul-Genus Fusion,” in In The Making: Creative Options for Contemporary Art, Linda Weintraub, d.a.p./Distributed Art Publishers, Inc.

"Singing in Animal Tongues: An Inner Journey," Jan Harrison, Performing Arts Journal, 97:28-38 "Jan Harrison's modern surrealism" Lynn Woods, Hudson Valley One "Life or Death" by Brainard Carey, Praxis “Crossing Over to Jan Harrison,” George Quasha, “Jan Harrison: Myths for Our Time,” Ann Pollak, Dialogue Magazine, “Jan Harrison, Audrey Skoudas: Ten Solo Exhibitions, Wright State University Gallery,” Elizabeth Hoxie, New Art Examiner Jan Harrison’s website: Ask ART: Performing Arts Journal podcast interview

The Avro 562 Avis was a two-seat light biplane designed and built by the A. V. Roe and Company Limited at Hamble for the 1924 Lympne Light Aeroplane Trials; the Avis was a single-bay unstaggered biplane with full-span ailerons on lower wings. It had a fixed landing gear with a tailskid and could be powered by a nose-mounted 32 hp Bristol Cherub II engine or a 35 hp Blackburne Thrush radial piston engine, it had tandem open cockpits. First flown with the Thrush engine prior to the trials, it was refitted with the Cherub, first flown with this engine by Bert Hinkler at Lympne on 30 September 1924. On the next day it won the Grosvenor Cup at a speed of 65.87 mph. For the 1926 trials it was re-engined with a 38 hp Blackburne Thrush, being eliminated after a forced landing. In 1927, it was re-engined again with a Bristol Cherub I and passed into private ownership until it was scrapped in 1931. Data from Avro Aircraft since 1908. General characteristics Crew: one Capacity: one Length: 24 ft 0 in Wingspan: 30 ft 1 in Height: 9 ft 0 in Wing area: 246 ft2 Empty weight: 590 lb Gross weight: 995 lb Powerplant: 1 × Blackburne Thrush three-cylinder air-cooled radial engine, 35 hp Performance Maximum speed: 75 mph Aircraft of comparable role and era Hawker Cygnet Westland Widgeon Avro Avis – British Aircraft Directory

The 2018 Russian presidential election was held on 18 March 2018. Incumbent Vladimir Putin won reelection for his second consecutive term in office with 77% of the vote. Vladimir Zhirinovsky from the Liberal Democratic Party was the perennial candidate, having unsuccessfully run in five previous presidential elections. Other candidates included Pavel Grudinin, Sergey Baburin, Ksenia Sobchak, Maxim Suraykin, Boris Titov and Grigory Yavlinsky. Anti-corruption activist Alexei Navalny announced his intent to run in December 2016 but was barred from doing so due to a prior criminal conviction, which may have been politically motivated, for corruption. Navalny called for a boycott of the election, he had organized several public rallies against corruption among members of Putin's government. The incumbent Vladimir Putin was eligible to run, he declared his intent to do so on 6 December 2017, being expected to win. This came following several months of speculation throughout the second half of 2017 as, although he was expected to run for another term, Putin made evasive comments including that he had still not decided whether he would like to "step down" from the post of president, that he would "think about running", that he "hadn't yet decided whether to run for another term".

Different sources predicted that he would run as an independent to capitalize more support from the population, although he could have been nominated by the United Russia party as in 2012, Putin chose to run as an independent. The President of Russia is directly elected for a term of six years, since being extended from four years in 2008 during Dmitry Medvedev's administration. According to Article 81 of the Constitution of the Russian Federation, a candidate for president must be at least 35 years old, hold no dual nationality, have permanently resided in Russia for the past 10 years, cannot serve more than two terms consecutively. Parties with representation in the State Duma are able to nominate a candidate to run for the office while candidates from registered parties that are not in parliament have to collect at least 100,000 signatures. Independent candidates have to collect at least 300,000 signatures with no more than 7,500 from each federal subject of Russia and from action groups made up of at least 500 people.

The nomination process took place during Russia's winter holiday period, 31 January 2018 was the last day for submitting signatures in support of contested access candidates. On 3 March 2017, senators Andrey Klishas and Anatoly Shirokov submitted to the State Duma draft amendments to the electoral legislation. One of the amendments involves the transfer of elections from the second to the third Sunday in March, i.e. from 11 to 18 March 2018. According to article 5, paragraph 7 of Russian Federal law No. 19-FZ, "If the Sunday on which presidential elections are to be held coincides with the day preceding a public holiday, or this Sunday falls on week including a public holiday or this Sunday in is declared to be a working day, elections are appointed on the following Sunday". The second week of March includes International Women's Day, an official holiday in Russia; the bill passed through the State Duma and Federation Council without delay in May 2017 and was signed into law by Vladimir Putin on 1 June 2017.

On 15 December, the upper house of the Federal Assembly, the Federation Council confirmed that 18 March 2018 will be the date of the election beginning the process of campaigning and registration for candidates. This date is significant in the country as it is the fourth anniversary of Russian annexation of Crimea. A total of 97,000 polling stations were open across the country from 08:00 until 20:00 local time. Political parties represented in the State Duma or the legislative bodies of not less than one-third of the federal subjects could nominate a candidate without collecting signatures; the following parties could nominate candidates without collecting signatures: Civic Platform, the Communist Party of the Russian Federation, the Liberal Democratic Party of Russia, A Just Russia and United Russia. On 1 July 2017, Chairman of Rodina Aleksey Zhuravlyov announced that his party would only support incumbent president Vladimir Putin in the election. On 11 December, the leader of Civic Platform Rifat Shaykhutdinov said that his party would support Putin.

On 24 December, the leader of A Just Russia Sergey Mironov stated that his party would not put forward a candidate. Senior party member Mikhail Yemelyanov confirmed. Individuals belonging to a party without any seats in the State Duma had to collect 105,000 signatures to become candidates, while those running as independents had to collect 315,000 and to form a group of activists made up of at least 500 people. Multiple political commentators, including former presidential hopeful Irina Khakamada, talked about the difficulty of gathering signatures without the support of a political party, a hurdle which cast doubt on many of the claims of the large number of people who said that they would run for president as independents. However, according to CEC Chairwoman Ella Pamfilova, the conditions for contested-access candidates were easier than because such potential candidates no longer had to collect 1,000,000 signatures. Pamfilova incorrectly predicted that there could be more candidates in this election than there were in 2000, when 11 candidates contested the presidency.

In July 2017, Party of Growth announced that it would hold primaries t