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Mansa Musa was the ruler of the Mali Empire in West Africa. Details recorded here should be sourced; unknown information is left blank.
MORE →Reflects the personal views, recollections, and perspective of the author, Mike Davis.
This is a personal recollection on the Move fire on May 13, 1985
Decompression has several meanings, some of which are covered by several articles:
Source: Wikipedia. Article content is retrieved live through the MediaWiki API.
Decompression has several meanings, some of which are covered by several articles: Data decompression, the action of reversing data compression Decompression (physics), the release of pressure and the opposition of physical compression Decompression (altitude). the reduction of pressure and the related physiological effects due to increase in altitude or other equivalent reduction of ambient pressure below normal atmospheric pressure Decompression (diving), the reduction in pressure and the process of allowing dissolved inert gases to be eliminated from the tissues during ascent from a dive or while in a pressurised environment Decompression practice, the techniques and procedures for decompressing a diver Decompression theory, The study of safe and efficient decompression practice Uncontrolled decompression, catastrophic reduction of pressure in accidents involving pressure vessels such as aircraft Decompression (comics), in comic book storytelling, is the stylistic choice to tell a story mainly by visuals, with few words. Decompression (novel), a 2012 novel by Juli Zeh Decompression (surgery), a procedure used to reduce pressure on a compressed structure, such as spinal decompression Herniated disc decompression, a form of treatment for Spinal disc herniation, employed by chiropractors "Decompression" (The Outer Limits), an episode of the American television fiction series The Outer Limits Nerve decompression, a procedure to relieve direct pressure on a nerve Decompression sickness
The Unarchiver is a free data decompression utility, which supports more formats than Archive Utility (formerly known as BOMArchiveHelper), the built-in archive unpacker program in macOS. It can also handle filenames in various character encodings, created using operating system versions that use those character encodings. The Unarchiver does not compress files. A key feature of The Unarchiver is its ability to handle many old or obscure Mac OS Classic and Amiga archive formats, including StuffIt, Compact Pro, AmigaOS disk images, and LZH/LZX archives. The source code credits libxad, an Amiga file format library. Utility author Dag Ågren reverse engineered the StuffIt and StuffIt X formats. His work resulted in one of the most complete open source implementations of these proprietary formats.
Decompression tables, also known to divers as dive tables, are tabulated data, often in the form of printed cards or booklets, that allow people to determine a decompression schedule that is acceptably safe for a given dive or other hyperbaric exposure profile and breathing gas. Decompression tables represent procedures recommended for decompression from hyperbaric exposures in a continuum of possibilities by schedules tabulated for discrete cases of such exposures chosen for practicality and convenience of the user. They may represent data from theoretical decompression models or empirical data from series of tests on human subjects, or combinations thereof, and may be empirically adjusted to reduce risk or improve decompression efficiency. The availability of dive computers which can apply algorithms in real time to calculate the personal decompression status of a diver have to a large extent supplanted decompression tables for recreational and scientific divers, but tables remain a practical and convenient method for deciding decompression schedules for people exposed to similar but not necessarily identical pressure profiles, particularly when they are to be decompressed as a group, such as saturation divers and compressed air workers. With decompression tables, it is generally assumed that the hyperbaric exposure, or dive profile, is a square profile, meaning that the diver descends to maximum depth immediately and stays at the same depth until resurfacing (approximating a rectangular outline when drawn in a coordinate system where one axis is depth and the other is duration). Some dive tables also assume the physical condition or acceptance of a specific level of risk from the diver. Some recreational dive tables only provide for no-stop dives at sea level sites, but the more complete tables can take into account staged decompression dives and dives performed at altitude.
In information theory, data compression, source coding, or bit-rate reduction is the process of encoding information using fewer bits than the original representation. Any particular compression is either lossy or lossless. Lossless compression reduces bits by identifying and eliminating statistical redundancy. No information is lost in lossless compression. Lossy compression reduces bits by removing unnecessary or less important information. Typically, a device that performs data compression is referred to as an encoder, and one that performs the reversal of the process (decompression) as a decoder. The process of reducing the size of a data file is often referred to as data compression. In the context of data transmission, it is called source coding: encoding is done at the source of the data before it is stored or transmitted. Source coding should not be confused with channel coding, for error detection and correction or line coding, the means for mapping data onto a signal. Data compression algorithms present a space–time complexity trade-off between the bytes needed to store or transmit information, and the computational resources needed to perform the encoding and decoding. The design of data compression schemes involves balancing the degree of compression, the amount of distortion introduced (when using lossy data compression), and the computational resources or time required to compress and decompress the data.
Before the 1921 destruction of Tulsa’s Greenwood District, Black residents had created a remarkable center of business and community life. The district included stores, professional offices, entertainment venues and homes owned by Black citizens. Understanding Greenwood means learning what was built—not only what was burned.
MORE →Mae Jemison, aboard Space Shuttle Endeavour in 1992.