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HandWiki is the world's largest wiki-style encyclopedia dedicated to science, technology and computing. It allows you to create and edit articles as long as you have external citations and login account. In addition, this is a content management environment that can be used for collaborative editing of original scholarly content, such as books, manuals, monographs and tutorials.

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LINPACK Benchmarks
The LINPACK Benchmarks are a measure of a system's floating-point computing power. Introduced by Jack Dongarra, they measure how fast a computer solves a dense n by n system of linear equations Ax = b, which is a common task in engineering. The latest version of these benchmarks is used to build the TOP500 list, ranking the world's most powerful supercomputers. The aim is to approximate how fast a computer will perform when solving real problems. It is a simplification, since no single computational task can reflect the overall performance of a computer system. Nevertheless, the LINPACK benchmark performance can provide a good correction over the peak performance provided by the manufacturer. The peak performance is the maximal theoretical performance a computer can achieve, calculated as the machine's frequency, in cycles per second, times the number of operations per cycle it can perform. The actual performance will always be lower than the peak performance. The performance of a computer is a complex issue that depends on many interconnected variables. The performance measured by the LINPACK benchmark consists of the number of 64-bit floating-point operations, generally additions and multiplications, a computer can perform per second, also known as FLOPS. However, a computer's performance when running actual applications is likely to be far behind the maximal performance it achieves running the appropriate LINPACK benchmark. The name of these benchmarks comes from the LINPACK package, a collection of algebra Fortran subroutines widely used in the 1980s, and initially tightly linked to the LINPACK benchmark. The LINPACK package has since been replaced by other libraries.
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  • 02 Dec 2022
Topic Review
Rhodococcus Fascians
Rhodococcus fascians (known as Corynebacterium fascians until 1984) is a Gram positive bacterial phytopathogen that causes leafy gall disease. R. fascians is the only phytopathogenic member of the genus Rhodococcus; its host range includes both dicotyledonous and monocotyledonous hosts. Because it commonly afflicts tobacco (Nicotiana) plants, it is an agriculturally significant pathogen.
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  • 02 Dec 2022
Topic Review
Indium-Mediated Allylation
Indium-Mediated Allylations (IMAs) are important chemical reactions for the formation of carbon–carbon bonds. This reaction has two steps: first, indium inserts itself between the carbon–halogen bond of an allyl halide, becoming the organoindium intermediate; second, this allyl indide intermediate reacts with an electrophile to synthesize one of a wide range of compounds, such as carbohydrates and antihelminthic drugs. This reaction is depicted in the scheme below: Although this reaction occurs in two steps, it is commonly done as a Barbier reaction where the indium, allyl halide, and electrophile are all mixed together in a one-pot process. Indium reacts more readily than other metals, such as Mg, Pb, Bi, or Zn and does not require a promoter or flammable organic solvent to drive the reaction. IMAs have advantages over other carbon bond forming reactions because of their ability to be carried out in water, which is cheap and environmentally friendly. Therefore, these reactions represent Green chemistry, providing a safer alternative to the very common Grignard reaction, performed with Mg. Reactions yield high stereo- and regio-selectivity with few by-products making it easy to purify the desired product.
  • 1.9K
  • 02 Dec 2022
Topic Review
BMDFM
Binary Modular Dataflow Machine (BMDFM) is software that enables running an application in parallel on shared memory symmetric multiprocessing (SMP) computers using the multiple processors to speed up the execution of single applications. BMDFM automatically identifies and exploits parallelism due to the static and mainly dynamic scheduling of the dataflow instruction sequences derived from the formerly sequential program. BMDFM dynamic scheduling subsystem performs a symmetric multiprocessing (SMP) emulation of a tagged-token dataflow machine to provide the transparent dataflow semantics for the applications. No directives for parallel execution are needed.
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  • 02 Dec 2022
Topic Review
Kumarakom
Kumarakom is a popular tourism destination located near the city of Kottayam (10 kilometres (6 mi)), in Kerala, India , famous for its backwater tourism. It is set in the backdrop of the Vembanad Lake, the largest lake in the state of Kerala.
  • 1.2K
  • 02 Dec 2022
Topic Review
Buddhology
Buddhology is the study of the Buddha or Buddhahood. The term is also used as a synonym for Buddhist Studies, contemporary academic investigation of Buddhism. There are varied and nuanced understandings of the precise nature of a Buddha expressed in the different Buddhist traditions and movements.
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  • 02 Dec 2022
Topic Review
Mineral Deficiency
Mineral deficiency is a lack of the dietary minerals, the micronutrients that are needed for an organism's proper health. The cause may be a poor diet, impaired uptake of the minerals that are consumed, or a dysfunction in the organism's use of the mineral after it is absorbed. These deficiencies can result in many disorders including anemia and goitre. Examples of mineral deficiency include, zinc deficiency, iron deficiency, and magnesium deficiency.
  • 1.3K
  • 02 Dec 2022
Topic Review
Envy-Free Cake-Cutting
An envy-free cake-cutting is a kind of fair cake-cutting. It is a division of a heterogeneous resource ("cake") that satisfies the envy-free criterion, namely, that every partner feels that their allocated share is at least as good as any other share, according to their own subjective valuation. When there are only two partners, the problem is easy and has been solved in Biblical times by the divide and choose protocol. When there are three or more partners, the problem becomes much more challenging. Two major variants of the problem have been studied: Connected pieces, e.g. if the cake is a 1-dimensional interval then each partner must receive a single sub-interval. If there are n partners, only n−1 cuts are needed. General pieces, e.g. if the cake is a 1-dimensional interval then each partner can receive a union of disjoint sub-intervals.
  • 1.3K
  • 02 Dec 2022
Topic Review
Resource Monotonicity
Resource monotonicity (RM; aka aggregate monotonicity) is a principle of fair division. It says that, if there are more resources to share, then all agents should be weakly better off; no agent should lose from the increase in resources. The RM principle has been studied in various division problems.
  • 1.0K
  • 02 Dec 2022
Topic Review
Agriculture in Ancient Mesopotamia
Agriculture was the main economic activity in ancient Mesopotamia. Operating under harsh constraints, notably the arid climate, the Mesopotamian farmers developed effective strategies that enabled them to support the development of the first states, the first cities, and then the first known empires, under the supervision of the institutions which dominated the economy: the royal and provincial palaces, the temples, and the domains of the elites. They focused above all on the cultivation of cereals (particularly barley) and sheep farming, but also farmed legumes, as well as date palms in the south and grapes in the north. In reality, there were two types of Mesopotamian agriculture, corresponding to the two main ecological domains, which largely overlapped with cultural distinctions. The agriculture of southern or Lower Mesopotamia, the land of Sumer and Akkad, which later became Babylonia received almost no rain and required large scale irrigation works which were supervised by temple estates, but could produce high returns. The agriculture of Northern or Upper Mesopotamia, the land that would eventually become Assyria, had enough rainfall to allow dry agriculture most of the time so that irrigation and large institutional estates were less important, but the returns were also usually lower.
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  • 02 Dec 2022
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