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Paging

In computer operating systems, paging is a memory management scheme by which a computer stores and retrieves data from secondary storage for use in main memory. In this scheme, the operating system retrieves data from secondary storage in same-size blocks called pages. Paging is an important part of virtual memory implementations in modern operating systems, using secondary storage to let programs exceed the size of available physical memory. For simplicity, main memory is called "RAM" and secondary storage is called "disk", but the concepts do not depend on whether these terms apply to a specific computer system. Ferranti introduced paging on the Atlas, but the first mass-market memory pages were concepts in computer architecture, regardless of whether a page moved between RAM and disk. For example, on the PDP-8, 7 of the instruction bits comprised a memory address that selected one of 128 words; this zone of memory was called a page. This use of the term is now rare. In the 1960s, swapping was an early virtual memory technique.

An entire program would be "swapped out" from RAM to disk, another one would be swapped in. A swapped-out program would be current but its execution would be suspended while its RAM was in use by another program. A program might include multiple overlays. Overlays are not a method of paging RAM to disk but of minimizing the program's RAM use. Subsequent architectures used memory segmentation, individual program segments became the units exchanged between disk and RAM. A segment was the program's entire code segment or data segment, or sometimes other large data structures; these segments had to be contiguous when resident in RAM, requiring additional computation and movement to remedy fragmentation. The invention of the page table let the processor operate on arbitrary pages anywhere in RAM as a contiguous logical address space; these pages became the units exchanged between disk and RAM. When a process tries to reference a page not present in RAM, the processor treats this invalid memory reference as a page fault and transfers control from the program to the operating system.

The operating system must: Determine the location of the data on disk. Obtain an empty page frame in RAM to use as a container for the data. Load the requested data into the available page frame. Update the page table to refer to the new page frame. Return control to the program, transparently retrying the instruction; when all page frames are in use, the operating system must select a page frame to reuse for the page the program now needs. If the evicted page frame was dynamically allocated by a program to hold data, or if a program modified it since it was read into RAM, it must be written out to disk before being freed. If a program references the evicted page, another page fault occurs and the page must be read back into RAM; the method the operating system uses to select the page frame to reuse, its page replacement algorithm, is important to efficiency. The operating system predicts the page frame least to be needed soon through the least used algorithm or an algorithm based on the program's working set.

To further increase responsiveness, paging systems may predict which pages will be needed soon, preemptively loading them into RAM before a program references them. Demand paging When pure demand paging is used, pages are loaded only. A program from a memory mapped file begins execution with none of its pages in RAM; as the program commits page faults, the operating system copies the needed pages from a file, e.g. memory-mapped file, paging file, or a swap partition containing the page data into RAM. Anticipatory paging This technique, sometimes called swap prefetch, predicts which pages will be referenced soon, to minimize future page faults. For example, after reading a page to service a page fault, the operating system may read the next few pages though they are not yet needed. If a program ends, the operating system may delay freeing its pages, in case the user runs the same program again. Free page queue and reclamation The free page queue is a list of page frames that are available for assignment.

Preventing this queue from being empty minimizes the computing necessary to service a page fault. Some operating systems periodically look for pages that have not been referenced and free the page frame and add it to the free page queue, a process known as "page stealing"; some operating systems support page reclamation. Pre-cleaning The operating system may periodically pre-clean dirty pages: write modified pages back to disk though they might be further modified; this minimizes the amount of cleaning needed to obtain new page frames at the moment a new program starts or a new data file is opened, improves responsiveness. After completing initialization, most programs operate on a small number of code and data pages compared to the total memory the program requires; the pages most accessed are called the working set. When the working set is a small percentage of the system's total number of pages, virtual memory systems work most efficiently and an insignificant amount of computing is spent resolving page faults.

As the working

Kinau (crater)

Kinau is a small, eroded lunar impact crater, located in the low southern latitudes of the Moon. It lies to the southeast of the crater Jacobi, about far to the north-northwest of Pentland, it is 42 kilometers in two kilometers deep. It may be from the Pre-Nectarian period, 4.55 to 3.85 billion years ago. The northwestern rim and inner wall of this crater has been damaged by impacts, is overlaid by a pair of small, cup-shaped craters; the remainder of the rim is worn and somewhat distorted into a hexagonal shape, with several small craterlets along the rim edge. The inner walls are low, the interior floor is featureless except for a few tiny craterlets. There is a low rise near the midpoint, attached to the small crater to the northwest; the crater is named after 19th century German priest and amateur astronomer Adolph Gottfried Kinau. By convention these features are identified on Lunar maps by placing the letter on the side of the crater midpoint, closest to Kinau. ^ The botanist C. A. Kinau was struck from the official list of the USGS in April 2007 and replaced by the correct eponym Adolph Gottfried Kinau

Cedar Mountain Formation

The Cedar Mountain Formation is the name given to a distinctive sedimentary geologic formation in eastern Utah. The formation was named for Cedar Mountain in northern Emery County, where William Lee Stokes first studied the exposures in 1944; the formation occurs between the underlying Morrison Formation and overlying Naturita Formation. It is composed of non-marine sediments, that is, sediments deposited in rivers, lakes and on flood plains. Based on various fossils and radiometric dates, the Cedar Mountain Formation was deposited during the last half of the Early Cretaceous Epoch, about 127 - 98 million years ago, it has lithography similar to the Burro Canyon Formation in the region. Dinosaur fossils occur throughout the formation, but their study has only occurred since the early 1990s; the dinosaurs in the lower part of the formation differ from those in the upper part. These two dinosaur assemblages, characterized by distinct dinosaurs, show the replacement of older, European-like dinosaurs with younger, Asian-like dinosaurs as the North American Continental Plate drifted westward.

A middle dinosaur assemblage may be present. The Cedar Mountain Formation is sandwiched between the Morrison Formation below and the Naturita Formation and Mancos Shale above; the youngest date for Morrison just below the Cedar Mountain Formation is 148.1 ± 0.5 Ma. or lower Tithonian. The Jurassic-Cretaceous boundary in western North America is marked by an unconformity of variable length, signifies 10-49 million years of missing geologic time; this boundary between the Morrison and Cedar Mountain is marked by a horizon of carbonate nodules or by polished pebbles that are gastroliths. Although not part of the Cedar Mountain Formation, the Naturita Formation overlies the Cedar Mountain and marks the encroaching Western Interior Seaway; the Naturita is not uniformly distributed and was eroded away in places by the advancing Seaway so that the marine shales of the Mancos Formation lay directly on the Mussentuchit or its equivalent. The name Dakota Formation has been improperly used for these strata.

Only did the 125 m thick formation get subdivided into smaller, distinctive beds called members. There is a debate as to whether there are five members or four depending whether the Buckhorn Conglomerate is considered to be at the top of the Morrison Formation or at the base of the Cedar Mountain Formation. In ascending order the remaining members are the Yellow Cat Member, Poison Strip Sandstone, Ruby Ranch Member, the Mussentuchit Member; each of these members are named after a geographic area. The Buckhorn Conglomerate is considered the lowermost member of the Cedar Mountain Formation in the region of the San Raphael Swell by Stokes, it is named for exposures near Buckhorn Reservoir near Cedar Mountain. Its position below the Ruby Ranch Member suggests that it may be equivalent to the channel sandstones in the Yellow Cat Member and the Poison Strip Sandstone farther to the east; this idea is strengthened by the similar composition of the gravels in these members, but a direct correlation has not yet been established.

The Yellow Cat Member is named for exposures near the Yellow Cat mining area north of Arches National Park. It is limited to the eastern portions of the formation and is thickest near Arches National Monument; the member is composed of some lenses of sandstone. The mudstones were deposited on flood plains, show evidence of ancient soil development called paleosols; the mudstones originated as flood deposits from river channels that are marked by the sandstone lenses. Considered Barremian, the latest radiometric and paleopalinological studies conclude that the Yellow Member is older, with deposition occurring from the middle Berriasian to early Hauterivian stages; the Poison Strip Sandstone was named for prominent, cliff-forming sandstones in the Poison Strip uranium district north of Arches National Monument. It is a series of sandstones that were deposited in river channels, lesser amounts of mudstones and limestones that were deposited on the flood plain and small ponds; the Poison Strip Sandstone may represent a meandering river complex.

Based on the position of the Poison Strip between the Yellow Cat and Ruby Ranch members, it was latest Barremian to earliest Aptian. Carbonate growths appear on bones in the quarry; the Poison Strip Sandstone was the source of Tony's Bone Bed, a significant concentration of dinosaur bones. Before it was discovered, only possible Sauropelta remains and the isolated bones of sauropods and theropods had been recovered from the Poison Strip member. Volunteers from the Denver Museum of Natural History discovered Tony's Bone Bed in 1998, 3.75m below the top of the member. The quality of the preserved remains in Tony's Bone Bed are "highly variable"; the condition of many of its fossils suggest the deposit accumulated gradually. Many of the bones seem to have been trampled before burial, some of the ends of bones are missing and were removed by scavengers. None of the bones were preserved articulated with each other. All of this suggests a significant period of time between the deaths of the animals and their final entombment.

Tony's Bonebed accumulated over time when the water in the river channel was low during the dry season. The Ruby Ranch Member is the most distinctive member of the Cedar Mountain, it was named for exposures on the Ruby Ranch located southeast of Utah. The member is composed of maroon mudstones

Vishal Amin

Vishal Amin is an American attorney and government official who serves as Intellectual Property Enforcement Coordinator. This position, sometimes referred to as "IP czar", was created by an act of Congress in 2008 in order to help the U. S. government combat online piracy. Prior to assuming his current role, Amin was senior counsel on the House Judiciary Committee. A graduate of Johns Hopkins University and Washington University School of Law, Amin served in the administration of George W. Bush as the White House's associate director for domestic policy and as special assistant and associate director for policy in the United States Department of Commerce. Cary Sherman, who serves as chairman and CEO of the Recording Industry Association of America, called Amin "a smart, thoughtful leader."

Tom R. Ferguson

Tom R. Ferguson is an American former professional rodeo cowboy, he was the Professional Rodeo Cowboys Association World All-Around Cowboy Champion for six consecutive years from 1974 to 1979 breaking the previous mark of five consecutive titles held by Larry Mahan. He was the 1974 World Tie-Down Roping Champion and the World Steer Wrestling Champion in 1977 and 1978. In 1999, he was inducted into the ProRodeo Hall of Fame. Born in Tahlequah, United States, on December 20, 1950, Tom Ferguson moved to California at the age of 3 and was chosen for the California Polytechnic State University rodeo team; the team took home multiple National Intercollegiate Rodeo Association championships, before Ferguson turned professional and returned to Miami, Oklahoma, in 1973. He joined the Rodeo Cowboys Association, which renamed itself to the Professional Rodeo Cowboys Association. Though Larry Mahan was the first to have six world all-around titles, Ferguson won six consecutively; the 5-foot-11 Native American rodeo cowboy specialized in calf steer wrestling.

In 1994, Ty Murray broke Mahan's and Ferguson's record of six titles and tied Ferguson's record of having won six titles consecutively. In 1998, Murray won his seventh title, surpassing both of them and holding the record for all-around titles at seven titles. In 2010, Trevor Brazile won his eighth all-around title. In 2018, Brazile won his 14th all-around title. In his first year as a professional rodeo cowboy, Ferguson came in second in the National Finals Rodeo in the All-Around Cowboy event, he accumulated more than $1 million in his rodeo career and was among the first rodeo cowboys to hire a manager. In 1974, he came second in the Steer Wrestling event. In 1976 he won the World Steer Wrestling Championship. Ferguson retired from rodeo in the late 1980s. 1999 ProRodeo Hall of Fame 1997 Ellensburg Rodeo Hall of Fame 1974 Rodeo Hall of Fame of the National Cowboy and Western Heritage Museum The Encyclopedia of Oklahoma History and Culture by the Oklahoma Historical Society Rodeo Hall of Fame Inductees

Bertha E. Reynolds

Bertha E. Reynolds, known in her community as "Dr. Bertha," was a rural doctor in south central Wisconsin, one of the state's first licensed female physicians, practicing medicine in and around Lone Rock and Avoca from 1902 to 1953. Bertha Elizabeth Reynolds was born in Thiensville, Wisconsin, in 1868, her parents and Margaret Reynolds, had migrated to Milwaukee, from Quebec, three years earlier. Reynolds grew up in Wisconsin, on her family's farm. In 1892, the Reynolds family moved to Lincoln, where Bertha enrolled in the Lincoln Normal School, afterwards working as a teacher, but she had long harbored a desire to become a doctor. One cousin, Walter H. Nielsen, the first dean of the medical school at Marquette University, discouraged her, indicating that medicine was an inappropriate career for women, she matriculated at the University of Nebraska, where she was discouraged from pursuing the MD. In 1898, thirty-year-old Reynolds enrolled in the Woman's Hospital Medical College of Chicago. Upon graduation she returned to Wisconsin, joining the Lone Rock, Wisconsin practice of a brother, Dr. Nelson Reynolds.

When Nelson Reynolds relocated to Milwaukee, Wisconsin, Dr. Bertha Reynolds became the area's only physician, her practice predating by about twenty years the better-known work of another pioneering Wisconsin physician, Dr. Kate Pelham Newcomb). A 1923 incident in which Reynolds, unable to reach patients due to Spring flooding, drafted then-unknown aviator Charles Lindbergh to transport her to patients across the Wisconsin River, has been well remembered by residents. Dr. Reynolds would sometimes take elderly patients into her own home until they were well enough to care for themselves. In the 1930s she served on the Richland County Children's Board. Reynolds attempted to retire in 1940, moving to Avoca, but when that town's only physician was called to service in World War II, she returned to work, serving Avoca patients until her second retirement in 1953. Reynolds received several awards during her lifetime, including a Distinguished Service Award from the University of Wisconsin–Madison.

She died October 31, 1961, at the age of 93, is buried in the Little Brown Church cemetery in Bear Valley. The town of Lone Rock dedicated a park to her memory, her medical apparatus, including her bag and scalpels, were donated to the State Historical Society of Wisconsin. Thayer, Earl R. and Steve Bussalachi. “First in their class: Wisconsin's pioneering women physicians.” Wisconsin Academy Review, 51-62. Coopey, Judith Redline. "A Life of Service." Wisconsin Trails, Vol 18, No.3, 30. Coopey, Judith Redline. "She Flew With Vol 48, No. 27, 2. Durbin, Richard D; the Wisconsin River: An Odyssey Through Time and Space. Spring Freshet Press, 1997. Gard, Robert Edward; this is Wisconsin. Wisconsin House, 1969. Sherr, Lynn. American Women's Gazetteer. Bantam Books, 1976. State Medical Society of Wisconsin. Wisconsin Medical Journal. Vol. 15, 1917