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🔗 Typography

A California job case is a kind of type case: a compartmentalized wooden box used to store movable type used in letterpress printing. It was the most popular and accepted of the job case designs in America. The California job case took its name from the Pacific Coast location of the foundries that made the case popular.

The defining characteristic of the California job case is the layout, documented by J. L. Ringwalt in the American Encyclopaedia of Printing in 1871, as used by San Francisco printers. This modification of a previously popular case, the Italic, it was claimed reduced the compositor's hand travel as he set the pieces of type into his composing stick by more than half a mile per day. In the previous convention, upper- and lowercase type were kept in separate cases, or trays. This is why capital letters are called uppercase and the minuscules are lowercase. The combined case became popular during the western expansion of the United States in the 19th century.

🔗 Human rights 🔗 Korea 🔗 Correction and Detention Facilities 🔗 Korea/North Korea

Hwasong concentration camp (Chosŏn'gŭl: 화성 제16호 관리소, also spelled Hwasŏng or Hwaseong) is a labor camp in North Korea for political prisoners. The official name is Kwan-li-so (Penal-labor colony) No. 16.

🔗 United States 🔗 Computing 🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry 🔗 Iran 🔗 Computing/Software 🔗 Computing/Computer Security 🔗 Military history/Middle Eastern military history

Stuxnet is a malicious computer worm, first uncovered in 2010, thought to have been in development since at least 2005. Stuxnet targets supervisory control and data acquisition (SCADA) systems and is believed to be responsible for causing substantial damage to the nuclear program of Iran. Although neither country has openly admitted responsibility, the worm is widely understood to be a cyberweapon built jointly by the United States and Israel.

Stuxnet specifically targets programmable logic controllers (PLCs), which allow the automation of electromechanical processes such as those used to control machinery and industrial processes including gas centrifuges for separating nuclear material. Exploiting four zero-day flaws, Stuxnet functions by targeting machines using the Microsoft Windows operating system and networks, then seeking out Siemens Step7 software. Stuxnet reportedly compromised Iranian PLCs, collecting information on industrial systems and causing the fast-spinning centrifuges to tear themselves apart. Stuxnet's design and architecture are not domain-specific and it could be tailored as a platform for attacking modern supervisory control and data acquisition (SCADA) and PLC systems (e.g., in factory assembly lines or power plants), most of which are in Europe, Japan, and the US. Stuxnet reportedly ruined almost one-fifth of Iran's nuclear centrifuges. Targeting industrial control systems, the worm infected over 200,000 computers and caused 1,000 machines to physically degrade.

Stuxnet has three modules: a worm that executes all routines related to the main payload of the attack; a link file that automatically executes the propagated copies of the worm; and a rootkit component responsible for hiding all malicious files and processes, to prevent detection of Stuxnet. It is typically introduced to the target environment via an infected USB flash drive, thus crossing any air gap. The worm then propagates across the network, scanning for Siemens Step7 software on computers controlling a PLC. In the absence of either criterion, Stuxnet becomes dormant inside the computer. If both the conditions are fulfilled, Stuxnet introduces the infected rootkit onto the PLC and Step7 software, modifying the code and giving unexpected commands to the PLC while returning a loop of normal operation system values back to the users.

In 2015, Kaspersky Lab noted that the Equation Group had used two of the same zero-day attacks prior to their use in Stuxnet and commented that "the similar type of usage of both exploits together in different computer worms, at around the same time, indicates that the Equation Group and the Stuxnet developers are either the same or working closely together".

🔗 Internet 🔗 Computing 🔗 Computing/Software 🔗 Computing/Free and open-source software 🔗 JavaScript

Node.js is an open-source, cross-platform, JavaScript runtime environment that executes JavaScript code outside of a web browser. Node.js lets developers use JavaScript to write command line tools and for server-side scripting—running scripts server-side to produce dynamic web page content before the page is sent to the user's web browser. Consequently, Node.js represents a "JavaScript everywhere" paradigm, unifying web-application development around a single programming language, rather than different languages for server- and client-side scripts.

Though .js is the standard filename extension for JavaScript code, the name "Node.js" doesn't refer to a particular file in this context and is merely the name of the product. Node.js has an event-driven architecture capable of asynchronous I/O. These design choices aim to optimize throughput and scalability in web applications with many input/output operations, as well as for real-time Web applications (e.g., real-time communication programs and browser games).

The Node.js distributed development project was previously governed by the Node.js Foundation, and has now merged with the JS Foundation to form the OpenJS Foundation, which is facilitated by the Linux Foundation's Collaborative Projects program.

Corporate users of Node.js software include GoDaddy, Groupon, IBM, LinkedIn, Microsoft, Netflix, PayPal, Rakuten, SAP, Voxer, Walmart, and Yahoo!.

🔗 Computing

In computing, the Two Generals' Problem is a thought experiment meant to illustrate the pitfalls and design challenges of attempting to coordinate an action by communicating over an unreliable link. In the experiment, two generals are only able to communicate with one another by sending a messenger through enemy territory. The experiment asks how they might reach an agreement on the time to launch an attack, while knowing that any messenger they send could be captured.

It is related to the more general Byzantine Generals Problem and appears often in introductory classes about computer networking (particularly with regard to the Transmission Control Protocol, where it shows that TCP can't guarantee state consistency between endpoints and why this is the case), though it applies to any type of two-party communication where failures of communication are possible. A key concept in epistemic logic, this problem highlights the importance of common knowledge. Some authors also refer to this as the Two Generals' Paradox, the Two Armies Problem, or the Coordinated Attack Problem. The Two Generals' Problem was the first computer communication problem to be proved to be unsolvable. An important consequence of this proof is that generalizations like the Byzantine Generals problem are also unsolvable in the face of arbitrary communication failures, thus providing a base of realistic expectations for any distributed consistency protocols.

🔗 Music/Music genres

Black MIDI is a music genre consisting of compositions that use MIDI files to create a song or a remix containing a large number of notes, typically in the thousands, millions, billions, or even trillions. People who make black MIDIs are known as blackers. However, there are no specific criteria of what is considered "black"; as a result, pinpointing the exact origin of black MIDI is impossible.

🔗 Literature

"Belling the Cat" is a fable also known under the titles "The Bell and the Cat" and "The Mice in Council". Although often attributed to Aesop, it was not recorded before the Middle Ages and has been confused with the quite different fable of Classical origin titled The Cat and the Mice. In the classificatory system established for the fables by B. E. Perry, it is numbered 613, which is reserved for Mediaeval attributions outside the Aesopic canon.

🔗 Computing

Lambda lifting is a meta-process that restructures a computer program so that functions are defined independently of each other in a global scope. An individual "lift" transforms a local function into a global function. It is a two step process, consisting of;

• Eliminating free variables in the function by adding parameters.
• Moving functions from a restricted scope to broader or global scope.

The term "lambda lifting" was first introduced by Thomas Johnsson around 1982 and was historically considered as a mechanism for implementing functional programming languages. It is used in conjunction with other techniques in some modern compilers.

Lambda lifting is not the same as closure conversion. It requires all call sites to be adjusted (adding extra arguments to calls) and does not introduce a closure for the lifted lambda expression. In contrast, closure conversion does not require call sites to be adjusted but does introduce a closure for the lambda expression mapping free variables to values.

The technique may be used on individual functions, in code refactoring, to make a function usable outside the scope in which it was written. Lambda lifts may also be repeated, in order to transform the program. Repeated lifts may be used to convert a program written in lambda calculus into a set of recursive functions, without lambdas. This demonstrates the equivalence of programs written in lambda calculus and programs written as functions. However it does not demonstrate the soundness of lambda calculus for deduction, as the eta reduction used in lambda lifting is the step that introduces cardinality problems into the lambda calculus, because it removes the value from the variable, without first checking that there is only one value that satisfies the conditions on the variable (see Curry's paradox).

Lambda lifting is expensive on processing time for the compiler. An efficient implementation of lambda lifting is ${\displaystyle O(n^{2})}$ on processing time for the compiler.

In the untyped lambda calculus, where the basic types are functions, lifting may change the result of beta reduction of a lambda expression. The resulting functions will have the same meaning, in a mathematical sense, but are not regarded as the same function in the untyped lambda calculus. See also intensional versus extensional equality.

The reverse operation to lambda lifting is lambda dropping.

Lambda dropping may make the compilation of programs quicker for the compiler, and may also increase the efficiency of the resulting program, by reducing the number of parameters, and reducing the size of stack frames. However it makes a function harder to re-use. A dropped function is tied to its context, and can only be used in a different context if it is first lifted.

🔗 Astronomy 🔗 Central Asia 🔗 Museums 🔗 Central Asia/Uzbekistan

The Ulugh Beg Observatory is an observatory in Samarkand, Uzbekistan. Built in the 1420s by the Timurid astronomer Ulugh Beg. Islamic astronomers who worked at the observatory include Al-Kashi, Ali Qushji, and Ulugh Beg himself. The observatory was destroyed in 1449 and rediscovered in 1908.

🔗 Climate change 🔗 Environment 🔗 Plants 🔗 Arctic 🔗 Palaeontology 🔗 Geology

The Azolla event is a scenario hypothesized to have occurred in the middle Eocene epoch, around 49 million years ago, when blooms of the freshwater fern Azolla are thought to have happened in the Arctic Ocean. As they sank to the stagnant sea floor, they were incorporated into the sediment; the resulting draw-down of carbon dioxide has been speculated to have helped transform the planet from a "greenhouse Earth" state, hot enough for turtles and palm trees to prosper at the poles, to the current icehouse Earth known as the Late Cenozoic Ice Age.