Numbers Station
Numbers stations are shortwave radio stations of uncertain origin. They generally broadcast artificially generated voices reading streams of numbers, words, letters sometimes using a spelling alphabet, tunes or Morse code. They are in a wide variety of languages and the voices are usually female, though sometimes male or children’s voices are used. Evidence supports popular assumptions that the broadcasts are used to send messages to spies. This usage has not been publicly acknowledged by any government that may operate a numbers station, but in 2001, the United States tried the Cuban Five with spying for Cuba; they had received and decoded messages that had been broadcast from a Cuban numbers station. In June 2009, the United States similarly charged Walter Kendall Myers with conspiracy to spy for Cuba, and receiving and decoding messages broadcast from a numbers station operated by the Cuban Intelligence Service to further that conspiracy. It has been reported that the United States uses numbers stations to communicate encoded information to persons in other countries. Numbers stations appear and disappear over time although some follow regular schedules, and their overall activity has increased slightly since the early 1990s. This increase suggests that, as spy-related phenomena, they were not unique to the Cold War.
Buy anything from McMaster-Carr
I just discovered the magical website of McMaster-Carr. They will sell you nearly anything. Prices are rather high, but everything looks to be really high quality, to the level of commercial / industrial demands. Best part: They have no minimum size order! Perfect for the hobbyist or experimenter. Here’s the huge list of things they sell, check out their very excellent website for pictures and more.
- Abrading & Polishing
- Building & Grounds
- Door & Equipment Hardware
- Electrical & Lighting
- Fabricating
- Fastening & Joining
- Filtration
- Flow & Level Control
- Furniture & Storage
- Hand Tools
- Heating & Cooling
- Lubricating
- Material Handling
- Measuring & Inspecting
- Office Supplies & Signs
- Plumbing & Janitorial
- Power Transmission
- Pressure & Temperature Control
- Pulling & Lifting
- Raw Materials
- Safety
- Sawing & Cutting
- Sealing
- Shipping
- Suspending
- Tubing, Hose, Pipe & Fittings
Jane’s Information Group
Jane’s Information Group is a publishing company specializing in transportation and military topics, which was founded by Fred T. Jane in 1898. Jane began by sketching ships as an enthusiast, and this gradually developed into an encyclopedic knowledge, culminating in the publishing of “All the World’s Fighting Ships”. The company Jane founded gradually branched out into other arenas of military expertise. The books and trade magazines published by Jane’s are often considered the de-facto public source of information on warfare and transportation systems. Major competitors include Defense News, Flight International and Aviation Week. Jane’s continues to provide open source intelligence in the defense, security, transport and law enforcement sectors.
via Jane’s Information Group – Wikipedia, the free encyclopedia.
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Proportional navigation
Proportional navigation is a guidance law used in some form or another by most homing air target missiles. It is based on the fact that two vehicles are on a collision course when their direct Line-of-Sight does not change direction. PN dictates that the missile velocity vector should rotate at a rate proportional to the rotation rate of the line of sight and in the same direction.
An = N' * L' * V
Where An is the acceleration perpendicular to missile velocity vector, N’ is the proportionality constant (dimensionless), L’ is the line of sight rate, and V is the velocity.
For example, if the line of sight rotates slowly from north to east, the missile should turn to the right by a certain factor faster than the LOS-rate. This factor is called the Navigation Constant K_nav.
via Proportional navigation – Wikipedia, the free encyclopedia.
Green Room
A green room is a room in a theater, studio, or other public venue for the accommodation of performers or speakers when not required on the stage. Its function is as a break/touch-up lounge so that performers do not have to go back to wardrobe/dressing rooms and are still easily accessible for their call. The first recorded use of the term was in 1701 but the origin of the term is unknown and is the source of many folk etymologies such as:
- The room was originally painted green to “relieve the eyes from the glare of the stage.” On the other hand, early stage lighting was by candlelight, so the “glare” might be apocryphal, a modern reference to electric stage lighting.
- It is sometimes said that the term green room was a response to limelight, though the name is merely a coincidence — “limelight” refers to calcium oxide, not to the fruit or color. Furthermore limelight was invented in 1820 and the term was used many years prior to that.
- Many actors experience nervous anxiety before a performance and one of the symptoms of nervousness is nausea. As a person who feels neauseous is often said to look “green”, so the “Green Room” is the place where the nervous actors wait.
- Some studies state that the green room was originally called the retaining room. The ensemble of a production would wait there for their appearance onstage, listening to the performance of the principal actors and critiquing their acting. When made aware of this practice, the leads began to call the retaining room the green room, mocking the (green) envy of these actors.
- In Restoration theatres, the main, seasoned actors waited for their entrances in the wings – or sometimes even at the sides of the stage – while the minor players, usually young, less experienced “green” actors, were banished behind the scenes. Hence, the backstage room was for the “green” players and came to be called the green-room.
- According to one theory, long before modern makeup was invented the actors had to apply makeup before a show and allow it to set up or cure before performing. Until the makeup was cured, it was green and people were advised to sit quietly in the green room until such time as the makeup was stable enough for performing. Uncured makeup is gone, but the green room lives on.
- In Shakespearean theatre actors would prepare for their performances in a room filled with plants and shrubs. It was believed that the moisture in the topiary was beneficial to the actors’ voices. Thus the green room may refer to the green plants in this stage preparation area.
CORDIC
CORDIC (digit-by-digit method, Volder’s algorithm) (for COordinate Rotation DIgital Computer) is a simple and efficient algorithm to calculate hyperbolic and trigonometric functions. It is commonly used when no hardware multiplier is available (e.g., simple microcontrollers and FPGAs) as the only operations it requires are addition, subtraction, bitshift and table lookup.
The modern CORDIC algorithm was first described in 1959 by Jack E. Volder. It was developed at the aeroelectronics department of Convair to replace the analog resolver in the B-58 bomber’s navigation computer, although it is similar to techniques published by Henry Briggs as early as 1624. John Stephen Walther at Hewlett-Packard further generalized the algorithm, allowing it to calculate hyperbolic and exponential functions, logarithms, multiplications, divisions, and square roots.
Originally, CORDIC was implemented using the binary numeral system. In the 1970s, decimal CORDIC became widely used in pocket calculators, most of which operate in binary-coded-decimal BCD rather than binary. CORDIC is particularly well-suited for handheld calculators, an application for which cost (eg, chip gate count has to be minimised) is much more important than is speed. Also the CORDIC subroutines for trigonometric and hyperbolic functions can share most of their code.
CORDIC is generally faster than other approaches when a hardware multiplier is unavailable (e.g., in a microcontroller based system), or when the number of gates required to implement the functions it supports should be minimized (e.g., in an FPGA). On the other hand, when a hardware multiplier is available (e.g., in a DSP microprocessor), table-lookup methods and power series are generally faster than CORDIC. These days, CORDIC algorithm is used extensively for various biomedical applications, especially in the FPGA domain.
Failure to thrive
Failure to thrive (FTT) is a medical term which denotes poor weight gain and physical growth failure over an extended period of time. Common usage refers to infancy. However, the term is also applied to geriatrics. As used by pediatricians, it covers poor physical growth of any cause and does not imply abnormal intellectual, social, or emotional development. Failure to thrive is weight consistently below the 3rd to the 5th percentile for age, progressive decrease in weight to below the 3rd to the 5th percentile, or a decrease in the percentile rank of 2 major growth parameters in a short period. The cause may be an identified medical condition or related to environmental factors. Both types relate to inadequate nutrition. Treatment aims to restore proper nutrition.
The other Cold War
The Cold War was an ice hockey game played between U.S. college rivals Michigan State University and the University of Michigan on Saturday, October 6, 2001. It set the world record for the largest crowd at an ice hockey game: 74,544.
Longtime rivals with Michigan in hockey (and other sports), MSU decided not to play this contest at East Lansing’s Munn Ice Arena, but instead set up an ice rink in the middle of the much larger Spartan Stadium, which they filled to 103.4% of capacity. This meant that 74,544 packed the Big Ten football stadium to watch the MSU Spartans and the Michigan Wolverines skate to a 3-3 tie. Two 300-piece marching bands were present on field and the game was internationally televised.
via Cold War (ice hockey) – Wikipedia, the free encyclopedia.
French Leave
French leave is “Leave of absence without permission or without announcing one’s departure”, including leaving a party without bidding farewell to the host. The intent behind this behavior is to leave without disturbing the host. The phrase was born at a time when the English and French cultures were heavily interlinked.
In French, the phrase “filer à l’anglaise” (English leave) means the same thing.
The term is especially used to mean the act of leisurely absence from a military unit. This comes from the rich history of Franco-English conflict; as Spain has a similar saying concerning the French, it may have come from the Napoleonic campaign in the Iberic Peninsula which pitted the French against an Anglo-Portuguese & Spanish alliance. The phrase has a perfect French and Italian equivalent in filer à l’anglaise and filarsela all’inglese, literally, “to take the English leave”.
Snowplow Game
In National Football League lore, the Snowplow Game refers to a regular-season game played between the Miami Dolphins and New England Patriots on December 12, 1982.
Playing in a heavy snowstorm at New England’s Schaefer Stadium in Foxborough, Massachusetts, the two teams remained scoreless late into the fourth quarter. With 4:45 left to go in the game and on-field conditions worsening, Patriots coach Ron Meyer directed snowplow operator Mark Henderson to clear a spot on the field specifically for placekicker John Smith. Matt Cavanaugh held for the kick. Miami coach Don Shula protested furiously but the field goal was good and the Patriots won the game by the final score of 3–0. The game ball was awarded to all-pro linebacker Steve Nelson, who subsequently donated it to his alma mater, North Dakota State University. Snow plow driver Henderson also received a game ball from a gracious Meyer after the game.
Henderson, who was a convict on a work release program at the time of the game, was released from prison a few years later and currently works in the construction business. When he was being interviewed by a TV reporter about the controversy, Henderson jokingly replied, “What are they gonna do, throw me in jail?” The following year, the NFL banned the use of snowplows on the field during a game.
The incident is commemorated with an interactive exhibit at the Hall at Patriot Place within the Patriots’ current home, Gillette Stadium. The plow itself, a John Deere Model 314 tractor with sweeper attached, hangs from the ceiling at the exhibit.