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🔗 United States/U.S. Government 🔗 United States

This article deals with the activities of the Central Intelligence Agency of the Federal government of the United States, that violate human rights.

🔗 Military history 🔗 Disaster management 🔗 Military history/Military aviation 🔗 Telecommunications 🔗 Computer Security 🔗 Computer Security/Computing 🔗 Syria 🔗 Israel 🔗 Military history/Middle Eastern military history 🔗 Explosives 🔗 Military history/Post-Cold War 🔗 Lebanon

On 17 September 2024, communication pagers simultaneously exploded across Lebanon and Syria in an apparent coordinated attack. Many of the pagers were owned by members of the Hezbollah militant group. Eighteen people were confirmed killed: eleven in Lebanon (including a child and at least two Hezbollah members) and seven in Syria. Around 4,000 people were reportedly injured, including Hezbollah members and civilians.

The blasts affected several Hezbollah strongholds, including Beirut's Dahieh suburb, southern Lebanon, and in the Beqaa Valley. Over 500 of the group's militants lost their eyesight. They called the incident the organization's "biggest security breach yet" and accused Israel of responsibility.

A day after Hamas launched its October 7 attacks on Israel in 2023, the Iranian-backed organization Hezbollah joined the conflict in support of Hamas by firing on Israel. This led to a series of cross-border military exchanges between Hezbollah and Israel. In February 2024, the secretary-general of Hezbollah, Hassan Nasrallah, told the group's members to use pagers instead of cell phones, claiming that Israel had infiltrated their cell phone network. Hezbollah then bought a new brand of pagers that were recently imported to Lebanon.

Earlier on the day of the explosion, Israel's domestic security agency, the Shin Bet, announced it had thwarted a Hezbollah plot to assassinate a former senior defense official using an explosive device.

Around 150 hospitals across Lebanon received victims of the attack, which saw chaotic scenes.

🔗 Geographical coordinates 🔗 Microformats

Geohash is a public domain geocode system invented in 2008 by Gustavo Niemeyer and (similar work in 1966) G.M. Morton, which encodes a geographic location into a short string of letters and digits. It is a hierarchical spatial data structure which subdivides space into buckets of grid shape, which is one of the many applications of what is known as a Z-order curve, and generally space-filling curves.

Geohashes offer properties like arbitrary precision and the possibility of gradually removing characters from the end of the code to reduce its size (and gradually lose precision). As a consequence of the gradual precision degradation, nearby places will often (but not always) present similar prefixes. While in rare cases nearby places may have very short shared prefixes, the longer their shared prefix is, the closer two places are guaranteed to be.

🔗 Electronics

In signal processing, the Nyquist frequency (or folding frequency), named after Harry Nyquist, is a characteristic of a sampler, which converts a continuous function or signal into a discrete sequence. For a given sampling rate (samples per second), the Nyquist frequency (cycles per second) is the frequency whose cycle-length (or period) is twice the interval between samples, thus 0.5 cycle/sample. For example, audio CDs have a sampling rate of 44100 samples/second. At 0.5 cycle/sample, the corresponding Nyquist frequency is 22050 cycles/second (Hz). Conversely, the Nyquist rate for sampling a 22050 Hz signal is 44100 samples/second.

When the highest frequency (bandwidth) of a signal is less than the Nyquist frequency of the sampler, the resulting discrete-time sequence is said to be free of the distortion known as aliasing, and the corresponding sample rate is said to be above the Nyquist rate for that particular signal.

In a typical application of sampling, one first chooses the highest frequency to be preserved and recreated, based on the expected content (voice, music, etc.) and desired fidelity. Then one inserts an anti-aliasing filter ahead of the sampler. Its job is to attenuate the frequencies above that limit. Finally, based on the characteristics of the filter, one chooses a sample rate (and corresponding Nyquist frequency) that will provide an acceptably small amount of aliasing. In applications where the sample rate is pre-determined (such as the CD rate), the filter is chosen based on the Nyquist frequency, rather than vice versa.

🔗 Espionage 🔗 Military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Intelligence

The Thing, also known as the Great Seal bug, was one of the first covert listening devices (or "bugs") to use passive techniques to transmit an audio signal. It was concealed inside a gift given by the Soviet Union to W. Averell Harriman, the United States Ambassador to the Soviet Union, on August 4, 1945. Because it was passive, needing electromagnetic energy from an outside source to become energized and activate, it is considered a predecessor of Radio-Frequency Identification (RFID) technology.

🔗 Physics

The Mpemba effect is a process in which hot water can freeze faster than cold water. The phenomenon is temperature-dependent. There is disagreement about the parameters required to produce the effect and about its theoretical basis.

The Mpemba effect is named after Tanzanian scientist Erasto Bartholomeo Mpemba (b.1950) who discovered it in 1963. There were preceding ancient accounts of similar phenomena, but these lacked sufficient detail to attempt verification.

🔗 Internet

Demand Progress is an internet activist-related entity encompassing a 501(c)4 arm sponsored by the 1630 Fund and a 501(c)3 arm sponsored by the New Venture Fund. It specializes in online-intensive and other grassroots activism to support Internet freedom, civil liberties, transparency, and human rights, and in opposition to censorship and corporate control of government. The organization was founded through a petition in opposition to the Combating Online Infringement and Counterfeits Act, sparking the movement that eventually defeated COICA's successor bills, the Stop Online Piracy Act and the PROTECT IP Act, two highly controversial pieces of United States legislation.

The organization has continued to fight for such causes in the wake of the successful shelving of these two acts. Demand Progress has also played key roles in forwarding the passage of net neutrality rules, blocking expansion of the Computer Fraud and Abuse Act, under which co-founder Aaron Swartz was indicted, and other key legislative efforts. Estimated membership numbers in early 2015 weigh in at over two million. As of late 2013, the organization encompasses the Demand Progress, Rootstrikers and Watchdog.net wings/brands.

🔗 Russia 🔗 Physics 🔗 Physics/relativity 🔗 Russia/science and education in Russia

The Novikov self-consistency principle, also known as the Novikov self-consistency conjecture and Larry Niven's law of conservation of history, is a principle developed by Russian physicist Igor Dmitriyevich Novikov in the mid-1980s. Novikov intended it to solve the problem of paradoxes in time travel, which is theoretically permitted in certain solutions of general relativity that contain what are known as closed timelike curves. The principle asserts that if an event exists that would cause a paradox or any "change" to the past whatsoever, then the probability of that event is zero. It would thus be impossible to create time paradoxes.

🔗 Military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry 🔗 Cold War

Blue Peacock, renamed from Blue Bunny and originally Brown Bunny, was a British tactical nuclear weapon project in the 1950s.

The project's goal was to store a number of ten-kiloton nuclear mines in Germany, to be placed on the North German Plain and, in the event of Soviet invasion from the east, detonated by wire or an eight-day timer to:

... not only destroy facilities and installations over a large area, but ... deny occupation of the area to an enemy for an appreciable time due to contamination ...