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WikiReader was a project to deliver an offline, text-only version of Wikipedia on a mobile device. The project was sponsored by Openmoko and made by Pandigital, and its source code has been released.

The project debuted an offline portable reader for Wikipedia in October 2009. Updates in multiple languages were available online and a twice-yearly offline update service delivered via Micro SD card was also available at a cost of $29 per year. WikiReader versions of the English Wikipedia, Wikiquote, Wiktionary and Project Gutenberg can be installed together on a user-supplied 16 GB Micro SDHC memory card. Unlike Wikipedia itself, the device features parental controls.

The device can also run programs written in the Forth programming language; a simple calculator program is included.

In late 2014, the WikiReader website and project itself were shut down and abandoned for unknown reasons. Existing WikiReaders no longer receive updates to their database. Devices, professionally produced updates, and homegrown updates continue to be available from the secondary markets (e.g. eBay and Amazon), as well as from community efforts centered around the WikiReader subreddit.

🔗 Mathematics 🔗 Archaeology

The Ishango bone is a bone tool and possible mathematical object, dated to the Upper Paleolithic era. It is a dark brown length of bone, the fibula of a baboon, with a sharp piece of quartz affixed to one end, perhaps for engraving. It is thought by some to be a tally stick, as it has a series of what has been interpreted as tally marks carved in three columns running the length of the tool, though it has also been suggested that the scratches might have been to create a better grip on the handle or for some other non-mathematical reason. Others argue that the marks on the object are non-random and that it was likely a kind of counting tool and used to perform simple mathematical procedures.

🔗 Computing 🔗 Systems 🔗 Business 🔗 Engineering 🔗 Systems/Systems engineering

Parkinson's law of triviality is C. Northcote Parkinson's 1957 argument that members of an organization give disproportionate weight to trivial issues. Parkinson provides the example of a fictional committee whose job was to approve the plans for a nuclear power plant spending the majority of its time on discussions about relatively minor but easy-to-grasp issues, such as what materials to use for the staff bike shed, while neglecting the proposed design of the plant itself, which is far more important and a far more difficult and complex task.

The law has been applied to software development and other activities. The terms bicycle-shed effect, bike-shed effect, and bike-shedding were coined as metaphors to illuminate the law of triviality; it was popularised in the Berkeley Software Distribution community by the Danish software developer Poul-Henning Kamp in 1999 and has spread from there to the whole software industry.

🔗 Apple Inc./Macintosh 🔗 Apple Inc. 🔗 Computing 🔗 Apple Inc./iOS

Mach () is a kernel developed at Carnegie Mellon University to support operating system research, primarily distributed and parallel computing. Mach is often mentioned as one of the earliest examples of a microkernel. However, not all versions of Mach are microkernels. Mach's derivatives are the basis of the operating system kernel in GNU Hurd and of Apple's XNU kernel used in macOS, iOS, iPadOS, tvOS, and watchOS.

The project at Carnegie Mellon ran from 1985 to 1994, ending with Mach 3.0, which is a true microkernel. Mach was developed as a replacement for the kernel in the BSD version of Unix, so no new operating system would have to be designed around it. Mach and its derivatives exist within a number of commercial operating systems. These include all using the XNU operating system kernel which incorporates an earlier non-microkernel Mach as a major component. The Mach virtual memory management system was also adopted in 4.4BSD by the BSD developers at CSRG, and appears in modern BSD-derived Unix systems, such as FreeBSD.

Mach is the logical successor to Carnegie Mellon's Accent kernel. The lead developer on the Mach project, Richard Rashid, has been working at Microsoft since 1991 in various top-level positions revolving around the Microsoft Research division. Another of the original Mach developers, Avie Tevanian, was formerly head of software at NeXT, then Chief Software Technology Officer at Apple Inc. until March 2006.

🔗 Computing 🔗 Computing/Computer hardware

The Honeywell 316 was a popular 16-bit minicomputer built by Honeywell starting in 1969. It is part of the Series 16, which includes the Models 116 (1965, discrete^: 4), 316 (1969), 416 (1966), 516 (1966) and DDP-716 (1969). They were commonly used for data acquisition and control, remote message concentration, clinical laboratory systems, Remote Job Entry and time-sharing. The Series-16 computers are all based on the DDP-116 designed by Gardner Hendrie at Computer Control Company, Inc. (3C) in 1964.

The 516 and later the 316 were used as Interface Message Processors (IMP) for the American ARPANET and the British NPL Network.

🔗 History 🔗 Architecture 🔗 Sociology 🔗 Urban studies and planning

New Urbanism is an urban design movement which promotes environmentally friendly habits by creating walkable neighborhoods containing a wide range of housing and job types. It arose in the United States in the early 1980s, and has gradually influenced many aspects of real estate development, urban planning, and municipal land-use strategies. New urbanism attempts to address the ills associated with urban sprawl and post-Second World War suburban development.

New Urbanism is strongly influenced by urban design practices that were prominent until the rise of the automobile prior to World War II; it encompasses ten basic principles such as traditional neighborhood design (TND) and transit-oriented development (TOD). These ideas can all be circled back to two concepts: building a sense of community and the development of ecological practices.

The organizing body for New Urbanism is the Congress for the New Urbanism, founded in 1993. Its foundational text is the Charter of the New Urbanism, which begins:

We advocate the restructuring of public policy and development practices to support the following principles: neighborhoods should be diverse in use and population; communities should be designed for the pedestrian and transit as well as the car; cities and towns should be shaped by physically defined and universally accessible public spaces and community institutions; urban places should be framed by architecture and landscape design that celebrate local history, climate, ecology, and building practice.

New Urbanists support regional planning for open space; context-appropriate architecture and planning; adequate provision of infrastructure such as sporting facilities, libraries and community centres; and the balanced development of jobs and housing. They believe their strategies can reduce traffic congestion by encouraging the population to ride bikes, walk, or take the train. They also hope that this set up will increase the supply of affordable housing and rein in suburban sprawl. The Charter of the New Urbanism also covers issues such as historic preservation, safe streets, green building, and the re-development of brownfield land. The ten Principles of Intelligent Urbanism also phrase guidelines for new urbanist approaches.

Architecturally, new urbanist developments are often accompanied by New Classical, postmodern, or vernacular styles, although that is not always the case.

A crinkle crankle wall, also known as a crinkum crankum, serpentine, ribbon or wavy wall, is an unusual type of garden wall built in a serpentine pattern with alternating curves.

The crinkle crankle wall economizes on bricks, despite its sinuous configuration, because it can be made just one brick thin. If a wall this thin were to be made in a straight line, without buttresses, it would easily topple over. The alternate convex and concave curves in the wall provide stability and help it to resist lateral forces.

"Crinkle crankle" is an ablaut reduplication, defined as something with bends and turns, first attested in 1598 (though "crinkle" and "crankle" have somewhat longer histories). However, it was not until the 18th century that the term began to be applied to wavy walls. At that time these garden walls were usually aligned east-west, so that one side faced south to catch the warming sun and were historically used for growing fruit.

Many crinkle crankle walls are found in the East Anglia region of England where the marshes of The Fens were drained by Dutch engineers starting in the mid-1600s. The walls' construction is attributed to these engineers who called them slangenmuur, meaning snake wall.  The county of Suffolk claims at least 50 examples, twice as many as in the whole of the rest of the country, and where crinkle crankle is said to derive from a local dialect. In the estate village of Easton the noted crinkle crankle wall running from the former manor house to All Saints' Church is supposed to be the longest existing example. In Lymington, Hampshire, there are at least two examples of crinkle crankle walls. The oldest is thought to have been constructed at the time of the Napoleonic Wars (1803–1815) by exiled Hanoverian soldiers living in the adjacent house.

As a minor part of a larger system of fortification, such a wall may have been used to force oncoming troops to break ranks from closed to open ranks, and further expose them to defensive assault.

Thomas Jefferson (1743–1826) incorporated so-called serpentine walls into the architecture of the University of Virginia, which he founded. Flanking both sides of its landmark rotunda and extending down the length of the lawn are ten pavilions, each with its own walled garden separated by crinkle crankle walls. Although some authorities claim Jefferson invented this design, he was merely adapting a well-established English style of construction. A university document in his own hand shows how he calculated the savings and combined aesthetics with utility.

🔗 Heraldry and vexillology

A broad arrow, of which a pheon is a variant, is a stylised representation of a metal arrowhead, comprising a tang and two barbs meeting at a point. It is a symbol used traditionally in heraldry, most notably in England, and later by the British government to mark government property. It became particularly associated with the Board of Ordnance, and later the War Department and the Ministry of Defence. It was exported to other parts of the British Empire, where it was used in similar official contexts.

In heraldry, the arrowhead generally points downwards, whereas in other contexts it more usually points upwards.

🔗 Biography 🔗 Mathematics 🔗 France 🔗 Biography/science and academia

Évariste Galois (; French: [evaʁist ɡalwa]; 25 October 1811 – 31 May 1832) was a French mathematician and political activist. While still in his teens, he was able to determine a necessary and sufficient condition for a polynomial to be solvable by radicals, thereby solving a problem that had been open for 350 years. His work laid the foundations for Galois theory and group theory, two major branches of abstract algebra.

Galois was a staunch republican and was heavily involved in the political turmoil that surrounded the French Revolution of 1830. As a result of his political activism, he was arrested repeatedly, serving one jail sentence of several months. For reasons that remain obscure, shortly after his release from prison, Galois fought in a duel and died of the wounds he suffered.

🔗 Computing 🔗 Computer science

In computer programming, COMEFROM (or COME FROM) is an obscure control flow structure used in some programming languages, originally as a joke. COMEFROM is roughly the opposite of GOTO in that it can take the execution state from any arbitrary point in code to a COMEFROM statement.

The point in code where the state transfer happens is usually given as a parameter to COMEFROM. Whether the transfer happens before or after the instruction at the specified transfer point depends on the language used. Depending on the language used, multiple COMEFROMs referencing the same departure point may be invalid, be non-deterministic, be executed in some sort of defined priority, or even induce parallel or otherwise concurrent execution as seen in Threaded Intercal.

A simple example of a "COMEFROM x" statement is a label x (which does not need to be physically located anywhere near its corresponding COMEFROM) that acts as a "trap door". When code execution reaches the label, control gets passed to the statement following the COMEFROM. This may also be conditional, passing control only if a condition is satisfied, analogous to a GOTO within an IF statement. The primary difference from GOTO is that GOTO only depends on the local structure of the code, while COMEFROM depends on the global structure – a GOTO transfers control when it reaches a line with a GOTO statement, while COMEFROM requires scanning the entire program or scope to see if any COMEFROM statements are in scope for the line, and then verifying if a condition is hit. The effect of this is primarily to make debugging (and understanding the control flow of the program) extremely difficult, since there is no indication near the line or label in question that control will mysteriously jump to another point of the program – one must study the entire program to see if any COMEFROM statements reference that line or label.

Debugger hooks can be used to implement a COMEFROM statement, as in the humorous Python goto module; see below. This also can be implemented with the gcc feature "asm goto" as used by the Linux kernel configuration option CONFIG_JUMP_LABEL. A no-op has its location stored, to be replaced by a jump to an executable fragment that at its end returns to the instruction after the no-op.