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πŸ”— DataHand

πŸ”— Occupational Safety and Health πŸ”— Disability

The DataHand keyboard was introduced in 1995 by DataHand Systems, Inc. It was invented by Dale J. Retter and was produced by Industrial Innovations as early as 1992. The keyboard consists of two completely separate "keyboards", one for the left hand and one for the right, that are molded to rest the user's hands on. This allows the user to place each hand wherever it is most comfortable to them. Each finger activates five buttons, the four compass directions as well as down. The thumbs also have five buttons, one inside and two outside as well as up and down. The button modules in which the fingers rest are adjustable to best fit the user's handsβ€”each side can be independently moved up and down, towards the palm or farther away.

This ergonomic layout allows for all typing to occur without any wrist motion, as well as without any finger extension. The keyboard layout is initially similar to a QWERTY keyboard, but the middle two columns of keys (i.e. H,Y,G...) have been delegated to sideways finger movements, and all of the keys outside of the main three rows are accessed through two additional modes, including a mode for mousing. There are three primary modes all together: letters, number and symbols, and function / mouse mode. Some practice is required. However, eventual typing speedups are possible.

Also of note is the button designβ€”instead of being spring-loaded, the buttons are held in place with magnets and are activated using optical sensors. This was done in order to dramatically reduce the finger workload while optimizing tactile feedback.

This unconventional keyboard was seen in the Jodie Foster movie Contact (1997) as the pilot's controls for the futuristic spaceship; and the spy movie Stormbreaker (2006). The Industrial Innovations version was featured on the television series Mighty Morphin Power Rangers. A black model is used by Agent Grasso while searching for Amanda Givens' Jeep in Shadow Conspiracy (1997), starring Charlie Sheen.

After the initial prototype was released in 1995, DataHand has released the Professional and Professional II with new bodies. The Professional II also has extended programming capabilities over the Professional, being able to record macros of keystrokes for convenient use.

DataHand Systems, Inc. announced in early 2008 that it was ceasing to market and sell its keyboards. The company web site states that due to supplier issues, the company will not sell the DataHand keyboard "until a new manufacturer can be identified". However, the company plans a final, limited production run to satisfy existing customers. In January 2009, the company's website started taking orders for a "limited number of new DataHand Pro II units".

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πŸ”— Bioluminescence

πŸ”— Chemistry πŸ”— Animals πŸ”— Molecular Biology/Molecular and Cell Biology

Bioluminescence is the production and emission of light by living organisms. It is a form of chemiluminescence. Bioluminescence occurs widely in marine vertebrates and invertebrates, as well as in some fungi, microorganisms including some bioluminescent bacteria, and terrestrial arthropods such as fireflies. In some animals, the light is bacteriogenic, produced by symbiotic bacteria such as those from the genus Vibrio; in others, it is autogenic, produced by the animals themselves.

In a general sense, the principal chemical reaction in bioluminescence involves a light-emitting molecule and an enzyme, generally called luciferin and luciferase, respectively. Because these are generic names, luciferins and luciferases are often distinguished by the species or group, e.g. firefly luciferin. In all characterized cases, the enzyme catalyzes the oxidation of the luciferin.

In some species, the luciferase requires other cofactors, such as calcium or magnesium ions, and sometimes also the energy-carrying molecule adenosine triphosphate (ATP). In evolution, luciferins vary little: one in particular, coelenterazine, is found in 11 different animal phyla, though in some of these, the animals obtain it through their diet. Conversely, luciferases vary widely between different species, which is evidence that bioluminescence has arisen over 40 times in evolutionary history.

Both Aristotle and Pliny the Elder mentioned that damp wood sometimes gives off a glow. Many centuries later Robert Boyle showed that oxygen was involved in the process, in both wood and glowworms. It was not until the late nineteenth century that bioluminescence was properly investigated. The phenomenon is widely distributed among animal groups, especially in marine environments. On land it occurs in fungi, bacteria and some groups of invertebrates, including insects.

The uses of bioluminescence by animals include counterillumination camouflage, mimicry of other animals, for example to lure prey, and signaling to other individuals of the same species, such as to attract mates. In the laboratory, luciferase-based systems are used in genetic engineering and biomedical research. Researchers are also investigating the possibility of using bioluminescent systems for street and decorative lighting, and a bioluminescent plant has been created.

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πŸ”— Mass Driver

πŸ”— Spaceflight

A mass driver or electromagnetic catapult is a proposed method of non-rocket spacelaunch which would use a linear motor to accelerate and catapult payloads up to high speeds. All existing and contemplated mass drivers use coils of wire energized by electricity to make electromagnets. Sequential firing of a row of electromagnets accelerates the payload along a path. After leaving the path, the payload continues to move due to momentum.

Although any device used to propel a ballistic payload is technically a mass driver, in this context a mass driver is essentially a coilgun that magnetically accelerates a package consisting of a magnetizable holder containing a payload. Once the payload has been accelerated, the two separate, and the holder is slowed and recycled for another payload.

Mass drivers can be used to propel spacecraft in three different ways: A large, ground-based mass driver could be used to launch spacecraft away from Earth, the Moon, or another body. A small mass driver could be on board a spacecraft, flinging pieces of material into space to propel itself. Another variation would have a massive facility on a moon or asteroid send projectiles to assist a distant craft.

Miniaturized mass drivers can also be used as weapons in a similar manner as classic firearms or cannon using chemical combustion. Hybrids between coilguns and railguns such as helical railguns are also possible.

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πŸ”— Berlin Key

The Berlin key (also known as, German, Schließzwangschlüssel, or, in English, forced-locking key) is a key for a type of door lock. It was designed to force people to close and lock their doors, usually a main entrance door or gate leading into a common yard or tenement block. The key was a solution to the problem of access via communal doors of such blocks (Mietskaserne) as early as the 19th century.

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πŸ”— Pointing machine

πŸ”— Visual arts

A pointing machine is a measuring tool used by stone sculptors and woodcarvers to accurately copy plaster, clay or wax sculpture models into wood or stone. In essence the device is a pointing needle that can be set to any position and then fixed. It further consists of brass or stainless steel rods and joints which can be placed into any position and then tightened. It is not actually a machine; its name is derived from the Italian macchinetta di punta. The invention of the tool has been ascribed to both the French sculptor and medallist Nicolas-Marie Gatteaux (1751–1832) and to the British sculptor John Bacon (1740–1799). It was later perfected by Canova. However, similar devices were used in ancient times, when the copying of Greek sculptures for the Roman market was a large industry.

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πŸ”— Curse of dimensionality

πŸ”— Computing πŸ”— Mathematics πŸ”— Statistics πŸ”— Cognitive science

The curse of dimensionality refers to various phenomena that arise when analyzing and organizing data in high-dimensional spaces (often with hundreds or thousands of dimensions) that do not occur in low-dimensional settings such as the three-dimensional physical space of everyday experience. The expression was coined by Richard E. Bellman when considering problems in dynamic programming.

Cursed phenomena occur in domains such as numerical analysis, sampling, combinatorics, machine learning, data mining and databases. The common theme of these problems is that when the dimensionality increases, the volume of the space increases so fast that the available data become sparse. This sparsity is problematic for any method that requires statistical significance. In order to obtain a statistically sound and reliable result, the amount of data needed to support the result often grows exponentially with the dimensionality. Also, organizing and searching data often relies on detecting areas where objects form groups with similar properties; in high dimensional data, however, all objects appear to be sparse and dissimilar in many ways, which prevents common data organization strategies from being efficient.

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πŸ”— Operation Popeye

πŸ”— Military history πŸ”— Military history/North American military history πŸ”— Military history/United States military history πŸ”— Military history/Asian military history πŸ”— Military history/Southeast Asian military history πŸ”— Vietnam

Operation Popeye (Project Controlled Weather Popeye / Motorpool / Intermediary-Compatriot) was a highly classified weather modification program in Southeast Asia during 1967–1972. The cloud seeding operation during the Vietnam War ran from March 20, 1967 until July 5, 1972 in an attempt to extend the monsoon season, specifically over areas of the Ho Chi Minh Trail. The operation was used to induce rain and extend the East Asian Monsoon season in support of U.S. government efforts related to the War in Southeast Asia.

The former U.S. Secretary of Defense, Robert S. McNamara, was aware that there might be objections raised by the international scientific community but said in a memo to the president that such objections had not in the past been a basis for prevention of military activities considered to be in the interests of U.S. national security.

The chemical weather modification program was conducted from Thailand over Cambodia, Laos, and Vietnam and allegedly sponsored by Secretary of State Henry Kissinger and CIA without the authorization of then Secretary of Defense Melvin Laird who had categorically denied to Congress that a program for modification of the weather for use as a tactical weapon even existed.

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πŸ”— IBM 7950 Harvest

πŸ”— Computing πŸ”— Computing/Early computers

The IBM 7950, also known as Harvest, was a one-of-a-kind adjunct to the Stretch computer which was installed at the United States National Security Agency (NSA). Built by IBM, it was delivered in 1962 and operated until 1976, when it was decommissioned. Harvest was designed to be used for cryptanalysis.

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πŸ”— Freedom to Roam

πŸ”— Environment πŸ”— Law πŸ”— Backpacking

The freedom to roam, or "everyman's right", is the general public's right to access certain public or privately owned land, lakes, and rivers for recreation and exercise. The right is sometimes called the right of public access to the wilderness or the "right to roam".

In Scotland, Finland, Iceland, Norway, Sweden, Estonia, Latvia, Lithuania, Austria, Czech Republic and Switzerland, the freedom to roam takes the form of general public rights which are sometimes codified in law. The access is ancient in parts of Northern Europe and has been regarded as sufficiently basic that it was not formalised in law until modern times. However, the right usually does not include any substantial economic exploitation, such as hunting or logging, or disruptive activities, such as making fires and driving offroad vehicles.

In England and Wales public access rights apply only to certain categories of mainly uncultivated land.

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πŸ”— Ferroelectric RAM

πŸ”— Computing πŸ”— Computing/Computer hardware

Ferroelectric RAM (FeRAM, F-RAM or FRAM) is a random-access memory similar in construction to DRAM but using a ferroelectric layer instead of a dielectric layer to achieve non-volatility. FeRAM is one of a growing number of alternative non-volatile random-access memory technologies that offer the same functionality as flash memory.

FeRAM's advantages over Flash include: lower power usage, faster write performance and a much greater maximum read/write endurance (about 1010 to 1014 cycles). FeRAMs have data retention times of more than 10 years at +85Β Β°C (up to many decades at lower temperatures). Market disadvantages of FeRAM are much lower storage densities than flash devices, storage capacity limitations and higher cost. Like DRAM, FeRAM's read process is destructive, necessitating a write-after-read architecture.

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