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🔗 Robotics 🔗 Software 🔗 Software/Computing

VxWorks is a real-time operating system (RTOS) developed as proprietary software by Wind River Systems, a wholly owned subsidiary of TPG Capital, US. First released in 1987, VxWorks is designed for use in embedded systems requiring real-time, deterministic performance and, in many cases, safety and security certification, for industries, such as aerospace and defense, medical devices, industrial equipment, robotics, energy, transportation, network infrastructure, automotive, and consumer electronics.

VxWorks supports Intel architecture, POWER architecture, ARM architectures and RISC-V. The RTOS can be used in multicore asymmetric multiprocessing (AMP), symmetric multiprocessing (SMP), and mixed modes and multi-OS (via Type 1 hypervisor) designs on 32- and 64-bit processors.

VxWorks comes with the kernel, middleware, board support packages, Wind River Workbench development suite and complementary third-party software and hardware technologies. In its latest release, VxWorks 7, the RTOS has been re-engineered for modularity and upgradeability so the OS kernel is separate from middleware, applications and other packages. Scalability, security, safety, connectivity, and graphics have been improved to address Internet of Things (IoT) needs.

🔗 Military history 🔗 United Kingdom 🔗 Military history/World War II 🔗 Animal rights 🔗 Animals 🔗 Military history/European military history 🔗 Military history/British military history

The British pet massacre was an event in 1939 in the United Kingdom where over 750,000 pets were killed in preparation for food shortages during World War II. It was referred to at the time as the September Holocaust, and later sources describe it as a "holocaust of pets". In London alone, during the first week of the Second World War around 400,000 companion animals, about 26% of all cats and dogs were killed.

No bombs were to fall on the UK mainland until April 1940.

Similar events happened in mainland Europe, for example, the killing of millions of farm animals in Denmark due to the lack of imported fodder for them.

🔗 Crime 🔗 Classical Greece and Rome 🔗 Greece 🔗 Egypt

Papyrus Oxyrhynchus 69 (P. Oxy. 69) is a complaint about a robbery, written in Greek. The manuscript was written on papyrus in the form of a sheet. It was discovered by Grenfell and Hunt in 1897 in Oxyrhynchus. The document was written on 21 November 190. Currently it is housed in the Haskell Oriental Institute at the University of Chicago (2061). The text was published by Grenfell and Hunt in 1898.

The beginning of the letter is lost. It is a petition to an unknown official describing the theft of some barley and asking that an investigation be carried out. The author is unknown. The measurements of the fragment are 178 by 115 mm. The description of the crime scene is quite detailed:

... they broke down a door that led into the public street and had been blocked up with bricks, probably using a log of wood as a battering-ram. They then entered the house and contented themselves with taking what was stored there, 10 artabae of barley, which they carried off by the same way. We guessed that this was removed piecemeal by the said door from the marks of a rope dragged along in that direction, and pointed out this fact to the chief of the police of that village and to the other officials.

10 artabae are equivalent to approximately 30–40 kilograms (66–88 lb) of barley.

🔗 Transport

Smeed's Law, named after R. J. Smeed, who first proposed the relationship in 1949, is a purported empirical rule relating traffic fatalities to traffic congestion as measured by the proxy of motor vehicle registrations and country population. The law proposes that increasing traffic volume (an increase in motor vehicle registrations) leads to an increase in fatalities per capita, but a decrease in fatalities per vehicle.

Smeed also predicted that the average speed of traffic in central London would always be nine miles per hour, because that is the minimum speed that people tolerate. He predicted that any intervention intended to speed traffic would only lead to more people driving at this "tolerable" speed unless there were any other disincentives against doing so.

His hypothesis in relation to road traffic safety has been refuted by several authors, who point out that fatalities per person have decreased in many countries, when the "Law" requires that they should increase as long as the number of vehicles per person continues to rise.

🔗 Russia 🔗 Russia/mass media in Russia 🔗 Radio Stations

The Pip is the nickname given by radio listeners to a shortwave radio station that broadcasts on the frequency 5448 kHz by day, and 3756 kHz during the night. It broadcasts short, repeated beeps at a rate of around 50 per minute, for 24 hours per day. The beep signal is occasionally interrupted by voice messages in Russian. The Pip has been active since around 1985, when its distinctive beeping sound was first recorded by listeners.

The station is commonly referred to as "The Pip" among English-speaking radio listeners. In Russia, it is known as Капля (Kaplya) "the drop". While its official name or callsign is not known, some of the voice transmissions begin with the code 8S1Shch (Cyrillic: 8С1Щ), which is generally considered to be the name of the station. However, this code may not be a callsign, but instead serve some other purpose. Radioscanner.ru identifies the owner of this station as a North-Caucasian military district communication center with callsign "Akacia" (ex-72nd communication center, Russian "72 узел связи штаба СКВО").

🔗 Chemicals

Aluminium oxynitride (marketed under the name ALON by Surmet Corporation) is a transparent ceramic composed of aluminium, oxygen and nitrogen. ALON is optically transparent (≥ 80%) in the near-ultraviolet, visible, and midwave-infrared regions of the electromagnetic spectrum. It is four times as hard as fused silica glass, 85% as hard as sapphire, and nearly 115% as hard as magnesium aluminate spinel. Since it has a cubic spinel structure, it can be fabricated to transparent windows, plates, domes, rods, tubes, and other forms using conventional ceramic powder processing techniques.

ALON is the hardest polycrystalline transparent ceramic available commercially. Because of its relatively low weight, distinctive optical and mechanical properties, and resistance to oxidation or radiation, it shows promise for applications such as bulletproof, blast-resistant, and optoelectronic windows. ALON-based armor has been shown to stop multiple armor-piercing projectiles of up to .50 BMG.

ALON is commercially available in sizes as large as 18-by-35-inch (460 mm × 890 mm; 46 cm × 89 cm) monolithic windows.

🔗 Physics 🔗 Physics/Acoustics

Thermoacoustic engines (sometimes called "TA engines") are thermoacoustic devices which use high-amplitude sound waves to pump heat from one place to another (this requires work, which is provided by the loudspeaker) or use a heat difference to produce work in the form of sound waves (these waves can then be converted into electrical current the same way as a microphone does).

These devices can be designed to use either standing wave or travelling wave.

Compared to vapor refrigerators, thermoacoustic refrigerators have no coolant and few moving parts (only the loudspeaker), therefore require no dynamic sealing or lubrication.

🔗 Poetry

The Star Gauge (Chinese: 璇璣圖; pinyin: Xuánjī Tú), or translated as "the armillary sphere chart", is the posthumous title given to a 4th-century Classical Chinese poem written by the Former Qin poet Su Hui for her husband during the Sixteen Kingdoms period. It consists of a 29 by 29 grid of characters, forming a reversible poem that can be read in different ways to form roughly 3,000 smaller rhyming poems. The outer border forms a single circular poem, thought to be both the first and the longest of its kind.

🔗 Classical Greece and Rome 🔗 Greece 🔗 Food and drink 🔗 Wine 🔗 Invention

A Pythagorean cup (also known as a Pythagoras cup, Greedy Cup, Tantalus cup or i koupa tis dikaiosynis) is a practical joke device in a form of a drinking cup, credited to Pythagoras of Samos. When it is filled beyond a certain point, a siphoning effect causes the cup to drain its entire contents through the base.

🔗 Disability 🔗 Writing systems 🔗 Constructed languages

Blissymbols or Blissymbolics is a constructed language conceived as an ideographic writing system called Semantography consisting of several hundred basic symbols, each representing a concept, which can be composed together to generate new symbols that represent new concepts. Blissymbols differ from most of the world's major writing systems in that the characters do not correspond at all to the sounds of any spoken language.

Blissymbols was published by Charles K. Bliss in 1949 and found use in the education of people with communication difficulties.