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🔗 Telecommunications

The Strowger switch is the first commercially successful electromechanical stepping switch telephone exchange system. It was developed by the Strowger Automatic Telephone Exchange Company founded in 1891 by Almon Brown Strowger. Because of its operational characteristics it is also known as a step-by-step (SXS) switch.

🔗 Computing 🔗 Computing/Software

86-DOS is a discontinued operating system developed and marketed by Seattle Computer Products (SCP) for its Intel 8086-based computer kit. Initially known as QDOS (Quick and Dirty Operating System), the name was changed to 86-DOS once SCP started licensing the operating system in 1980.

86-DOS had a command structure and application programming interface that imitated that of Digital Research's CP/M operating system, which made it easy to port programs from the latter. The system was licensed and then purchased by Microsoft and developed further as MS-DOS and PC DOS.

🔗 Trains 🔗 Bridges and Tunnels

The Gotthard Base Tunnel (GBT; German: Gotthard-Basistunnel, Italian: Galleria di base del San Gottardo, Romansh: Tunnel da basa dal Son Gottard) is a railway tunnel through the Alps in Switzerland. It opened on 1 June 2016, and full service began on 11 December 2016. With a route length of 57.09 km (35.5 mi), it is the world's longest railway and deepest traffic tunnel and the first flat, low-level route through the Alps. It lies at the heart of the Gotthard axis and constitutes the third tunnel connecting the cantons of Uri and Ticino, after the Gotthard Tunnel and the Gotthard Road Tunnel.

The link consists of two single-track tunnels connecting Erstfeld (Uri) with Bodio (Ticino) and passing below Sedrun (Graubünden). It is part of the New Railway Link through the Alps (NRLA) project, which also includes the Ceneri Base Tunnel further south (scheduled to open late 2020) and the Lötschberg Base Tunnel on the other main north–south axis. It is referred to as a "base tunnel" since it bypasses most of the existing Gotthard railway line, a winding mountain route opened in 1882 across the Saint-Gotthard Massif, which was operating at its capacity before the opening of the GBT. The new base tunnel establishes a direct route usable by high-speed rail and heavy freight trains.

The main purpose of the Gotthard Base Tunnel is to increase local transport capacity through the Alpine barrier, especially for freight, notably on the Rotterdam–Basel–Genoa corridor, and more specifically to shift freight volumes from trucks to freight trains. This both significantly reduces the danger of fatal road crashes involving trucks, and reduces the environmental damage caused by heavy trucks. The tunnel provides a faster connection between the canton of Ticino and the rest of Switzerland, as well as between northern and southern Europe, cutting the Basel/Zürich–Lugano–Milan journey time for passenger trains by one hour (and from Lucerne to Bellinzona by 45 minutes).

After 64 percent of Swiss voters accepted the NRLA project in a 1992 referendum, first preparatory and exploratory work began in 1996. The official start of construction began on 4 November 1999 at Amsteg. Drilling operations in the eastern tunnel were completed on 15 October 2010 in a breakthrough ceremony broadcast live on Swiss TV, and in the western tunnel on 23 March 2011. The tunnel's constructor, AlpTransit Gotthard AG, originally planned to hand over the tunnel to Swiss Federal Railways (SBB CFF FFS) in operating condition in December 2016 but, on 4 February 2014, the handover date was changed to 5 June 2016 with the start of an 850-day opening countdown calendar on the AlpTransit homepage. As of 1998, the total projected cost of the project was CHF 6.323 billion; as of December 2015, the final cost is projected as CHF 9.560 billion. Nine people died during construction.

🔗 Health and fitness

Calisthenics (American English) or callisthenics (British English) is a form of exercise consisting of a variety of movements that exercise large muscle groups (gross motor movements), such as running, standing, grasping, pushing, etc. These exercises are often performed rhythmically and with minimal equipment, as bodyweight exercises. They are intended to increase strength, fitness, and flexibility, through movements such as pulling, pushing, bending, jumping, or swinging, using one's body weight for resistance. Calisthenics can provide the benefits of muscular and aerobic conditioning, in addition to improving psychomotor skills such as balance, agility, and coordination.

Urban calisthenics is a form of street workout; calisthenics groups perform exercise routines in urban areas. Individuals and groups train to perform advanced calisthenics skills such as muscle-ups, levers, and various freestyle moves such as spins and flips.

Sports teams and military units often perform leader-directed group calisthenics as a form of synchronized physical training (often including a customized "call and response" routine) to increase group cohesion and discipline. Calisthenics is also popular as a component of physical education in primary and secondary schools over much of the globe.

In addition to general fitness, calisthenic exercises are often used as baseline physical evaluations for military organizations around the world. Two examples are the U.S. Army Physical Fitness Test and the U.S.M.C. Physical Fitness Test.

🔗 Amateur radio

The British Amateur Television Club (BATC) is the world's largest television technology club; it has members in the UK and all around the world and is a non-profit making club run by an elected committee of volunteers for the benefit of its members. Membership is open to all who are interested in television, amateur or professional, indeed the club has many members who work for major broadcasting companies.

🔗 Food and drink 🔗 Insects 🔗 Forestry

Shellac () is a resin secreted by the female lac bug on trees in the forests of India and Thailand. Chemically, it is mainly composed of aleuritic acid, jalaric acid, shellolic acid, and other natural waxes. It is processed and sold as dry flakes and dissolved in alcohol to make liquid shellac, which is used as a brush-on colorant, food glaze and wood finish. Shellac functions as a tough natural primer, sanding sealant, tannin-blocker, odour-blocker, stain, and high-gloss varnish. Shellac was once used in electrical applications as it possesses good insulation qualities and seals out moisture. Phonograph and 78 rpm gramophone records were made of shellac until they were replaced by vinyl long-playing records from 1948 onwards.

From the time shellac replaced oil and wax finishes in the 19th century, it was one of the dominant wood finishes in the western world until it was largely replaced by nitrocellulose lacquer in the 1920s and 1930s.

🔗 Internet culture

TSLAQ is a loose, international collective of largely anonymous short-sellers, skeptics, and researchers who openly criticize Tesla, Inc. and its CEO, Elon Musk. The group primarily organizes on Twitter, often using the $TSLAQ cashtag, and Reddit to coordinate efforts and share news, opinions, and analysis about the company and its stock. Edward Niedermeyer, in his book Ludicrous: The Unvarnished Story of Tesla Motors (2019), establishes the doxxing of Lawrence Fossi, a Seeking Alpha writer and Tesla short seller who uses the pseudonym Montana Skeptic, in July 2018 as the catalyst for the formation of TSLAQ. The group was the subject of a Real Vision video which included interviews with prominent members @TESLACharts and @Paul91701736.

TSLAQ highlights what they claim to be a variety of dangerous, deceptive, unlawful and fraudulent business practices by Tesla. Regular criticisms include knowingly selling Model S cars with a design flaw that could cause fires, reselling defective "lemon" cars, performing stealth recalls and requiring customers to sign non-disclosure agreements for "goodwill" repairs, issuing over-the-air updates to cover-up a fire risk in their batteries, publishing misleading safety statistics, delivering cars with lower-performance hardware than promised, taking months to issue customers refunds, and selling a Full Self-Driving package with the promise 1 million "robotaxis" by the end of 2020 despite the technology not yet being available. TSLAQ has also criticized Tesla and Musk for their attempts to intimidate and silence whistleblowers who have spoken out against the company. In addition, the group has highlighted Tesla's history of environmental violations, disregard for workers' safety, and Musk's excessive compensation package. As financial media producer Demetri Kofinas put it, TSLAQ believes Musk "to be a carnival barker running the biggest fraud in corporate America."

On occasion, TSLAQ has exchanged online verbal hostilities with Tesla fans and Elon Musk, who once tweeted with a prominent member and also tweeted personal information of another. While explicitly an online group, off-line activities performed by subgroups include aerial reconnaissance and on-the-ground observations of parking lots used by Tesla for storage.

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🔗 Aviation 🔗 Military history 🔗 Military history/Military aviation 🔗 Aviation/Aviation accident 🔗 Military history/Cold War 🔗 Military history/Russian, Soviet and CIS military history 🔗 Finland

Finnair Flight 915 (AY915) was a scheduled flight by Finnair from Tokyo, Japan, over the North Pole to Helsinki, Finland, on 23 December 1987. In 2014, Finnish media reported a claim by two of the flight’s pilots that the Soviet Union had fired a missile at the aircraft, which exploded less than 30 seconds before impact. The allegations came out only in September 2014, when Helsingin Sanomat, the leading Finnish daily newspaper, published an extensive article on the matter. The Finnish Broadcasting Corporation YLE reported on the article on the internet the same day.

When the matter came out, it caused outrage in Finland among those politicians and civil servants, to whom it should have been reported at the time, and it was widely publicised and commented upon in the Finnish media, amidst allegations of Finlandization.

The alleged incident has been compared to other similar incidents involving the Soviet Union, such as the Aero Kaleva in 1940, Aeroflot Flight 902 in 1962, Korean Air Lines Flight 902 in 1978, Korean Air Lines Flight 007 in 1983. Co-captain Kaukiainen said that the Finnair pilots decided to speak out on the matter after Malaysia Airlines Flight 17 had been shot down in Ukraine on 17 July 2014.

🔗 Shipwrecks

In maritime law, flotsam, jetsam, lagan, and derelict are specific kinds of shipwreck. The words have specific nautical meanings, with legal consequences in the law of admiralty and marine salvage. A shipwreck is defined as the remains of a ship that has been wrecked—a destroyed ship at sea, whether it has sunk or is floating on the surface of the water.