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Sensorvault is an internal Google database that contains records of users' historical geo-location data.^: 1

It has been used by law enforcement to obtain a geo-fence warrant and to search for all devices within the vicinity of a crime, (within a geo-fenced area)^{: 1 : 1} and after looking at those devices' movements and narrowing those devices down to potential suspects or witnesses, then asking Google for the information about the owners of those devices.^{: 1 : 1}

An animated image showing the definition of pi. A number line is marked off by a circle of unit diameter. Starting from zero, the circle "unrolls" its circumference. At one full turn, the unrolled circumference has extended to the point we call π. This number is real but irrational, transcendental, and cannot be constructed with compass and straightedge.

Animation credit: John Reid
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The Jacquard machine (French: [ʒakaʁ]) is a device fitted to a power loom that simplifies the process of manufacturing textiles with such complex patterns as brocade, damask and matelassé. It was invented by Joseph Marie Jacquard in 1804, based on earlier inventions by the Frenchmen Basile Bouchon (1725), Jean Baptiste Falcon (1728), and Jacques Vaucanson (1740). The machine was controlled by a "chain of cards"; a number of punched cards laced together into a continuous sequence. Multiple rows of holes were punched on each card, with one complete card corresponding to one row of the design. Several such paper cards, generally white in color, can be seen in the images below. Chains, like Bouchon's earlier use of paper tape, allowed sequences of any length to be constructed, not limited by the size of a card.

Both the Jacquard process and the necessary loom attachment are named after their inventor. This mechanism is probably one of the most important weaving inventions as Jacquard shedding made possible the automatic production of unlimited varieties of pattern weaving. The term "Jacquard" is not specific or limited to any particular loom, but rather refers to the added control mechanism that automates the patterning. The process can also be used for patterned knitwear and machine-knitted textiles, such as jerseys.

This use of replaceable punched cards to control a sequence of operations is considered an important step in the history of computing hardware.

The 100 Year Starship (100YSS) is a joint U.S. Defense Advanced Research Projects Agency (DARPA) and National Aeronautics and Space Administration (NASA) grant project to a private entity. The goal of the study is to create a business plan that can foster the research and technology needed for interstellar travel within 100 years.

A black start is the process of restoring an electric power station or a part of an electric grid to operation without relying on the external electric power transmission network to recover from a total or partial shutdown.

Normally, the electric power used within the plant is provided from the station's own generators. If all of the plant's main generators are shut down, station service power is provided by drawing power from the grid through the plant's transmission line. However, during a wide-area outage, off-site power from the grid is not available. In the absence of grid power, a so-called black start needs to be performed to bootstrap the power grid into operation.

To provide a black start, some power stations have small diesel generators, normally called the black start diesel generator (BSDG), which can be used to start larger generators (of several megawatts capacity), which in turn can be used to start the main power station generators. Generating plants using steam turbines require station service power of up to 10% of their capacity for boiler feedwater pumps, boiler forced-draft combustion air blowers, and for fuel preparation. It is uneconomical to provide such a large standby capacity at each station, so black-start power must be provided over designated tie lines from another station. Often hydroelectric power plants are designated as the black-start sources to restore network interconnections. A hydroelectric station needs very little initial power for starting purposes (just enough to open the intake gates and provide excitation current to the generator field coils), and can put a large block of power on line very quickly to allow start-up of fossil-fuel or nuclear stations. Certain types of combustion turbine can be configured for black start, providing another option in places without suitable hydroelectric plants. In 2017, a utility in Southern California successfully demonstrated the use of a battery-based energy-storage system to provide a black start, firing up a combined-cycle gas turbine from an idle state.

Free speech zones (also known as First Amendment zones, free speech cages, and protest zones) are areas set aside in public places for the purpose of political protesting. The First Amendment to the United States Constitution states that "Congress shall make no law ... abridging ... the right of the people peaceably to assemble, and to petition the Government for a redress of grievances." The existence of free speech zones is based on U.S. court decisions stipulating that the government may reasonably regulate the time, place, and manner – but not content – of expression.

The Supreme Court has developed a four-part analysis to evaluate the constitutionality of time, place and manner (TPM) restrictions. To pass muster under the First Amendment, TPM restrictions must be neutral with respect to content, be narrowly drawn, serve a significant government interest, and leave open alternative channels of communication. Application of this four-part analysis varies with the circumstances of each case, and typically requires lower standards for the restriction of obscenity and fighting words.

Free speech zones have been used at a variety of political gatherings. The stated purpose of free speech zones is to protect the safety of those attending the political gathering, or for the safety of the protesters themselves. Critics, however, suggest that such zones are "Orwellian", and that authorities use them in a heavy-handed manner to censor protesters by putting them literally out of sight of the mass media, hence the public, as well as visiting dignitaries. Though authorities generally deny specifically targeting protesters, on a number of occasions, these denials have been contradicted by subsequent court testimony. The American Civil Liberties Union (ACLU) has filed, with various degrees of success and failure, a number of lawsuits on the issue.

Though free speech zones existed prior to the Presidency of George W. Bush, it was during Bush's presidency that their scope was greatly expanded. These zones continued through the presidency of Barack Obama; he signed a bill in 2012 that expanded the power of the Secret Service to restrict speech and make arrests.

Many colleges and universities earlier instituted free speech zone rules during the Vietnam-era protests of the 1960s and 1970s. In recent years, a number of them have revised or removed these restrictions following student protests and lawsuits.

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.

Fabrice Bellard (French pronunciation: ​[fa.bʁis bɛ.laʁ]) is a computer programmer who created the FFmpeg and QEMU software projects. He has also developed a number of other programs, including the Tiny C Compiler.

The Matthew effect of accumulated advantage, Matthew principle, or Matthew effect for short, is sometimes summarized by the adage "the rich get richer and the poor get poorer". The concept is applicable to matters of fame or status, but may also be applied literally to cumulative advantage of economic capital. In the beginning, Matthew effects were primarily focused on the inequality in the way scientists were recognized for their work. However, Norman Storer, of Columbia University, led a new wave of research. He believed he discovered that the inequality that existed in the social sciences also existed in other institutions.

The term was coined by sociologist Robert K. Merton in 1968 and takes its name from the Parable of the talents or minas in the biblical Gospel of Matthew. Merton credited his collaborator and wife, sociologist Harriet Zuckerman, as co-author of the concept of the Matthew effect.

A 2019 report by the National Center for Education Statistics determined that mid to high literacy in the United States is 79% with 21% of American adults categorized as having "low level English literacy," including 4.1% classified as "functionally illiterate" and an additional 4% that could not participate. According to the U.S. Department of Education, 54% of adults in the United States have prose literacy below the 6th-grade level.

In many nations, the ability to read a simple sentence suffices as literacy, and was the previous standard for the U.S. The definition of literacy has changed greatly; the term is presently defined as the ability to use printed and written information to function in society, to achieve one's goals, and to develop one's knowledge and potential.

The United States Department of Education assesses literacy in the general population through its National Assessment of Adult Literacy (NAAL). The NAAL survey defines three types of literacy:

• prose literacy: the knowledge and skills needed to search, comprehend, and use continuous texts. Examples include editorials, news stories, brochures, and instructional materials.
• document literacy: the knowledge and skills needed to search, comprehend, and use non-continuous texts in various formats. Examples include job applications, payroll forms, transportation schedules, maps, tables, and drug and food labels.
• quantitative literacy: the knowledge and skills required to identify and perform computations, either alone or sequentially, using numbers embedded in printed materials. Examples include balancing a checkbook, figuring out tips, completing an order form, or determining an amount.

Modern jobs often demand a high level of literacy, and its lack in adults and adolescents has been studied extensively.

According to a 1992 survey, about 40 million adults had Level 1 literary competency, the lowest level, comprising understanding only basic written instructions. A number of reports and studies are published annually to monitor the nation's status, and initiatives to improve literacy rates are funded by government and external sources.