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The Weissman score is an efficiency metric for lossless compression applications, which was developed for fictional use. It compares both required time and compression ratio of measured applications, with those of a de facto standard according to the data type. It was developed by Tsachy Weissman, a professor at Stanford University, and Vinith Mishra, a graduate student, at the request of producers for HBO's television series Silicon Valley, about a fictional tech start-up.

The formula is the following; where r is the compression ratio, T is the time required to compress, the overlined ones are the same metrics for a standard compressor, and alpha is a scaling constant.

Weissman score was used in Dropbox Tech Blog to explain real-world work on lossless compression.

🔗 International relations 🔗 Norway 🔗 European Union

Norway is not a member state of the European Union (EU). However, it is associated with the Union through its membership in agreements in the European Economic Area (EEA) established in 1994, and by virtue of being a founding member of the European Free Trade Association (EFTA) which was founded in 1960, one of the two historically dominant western European trade blocs. Norway had considered joining the European Community and the European Union twice, but opted to decline following referendums in 1972 and 1994.

🔗 Aviation

In aviation, the sterile flight deck rule or sterile cockpit rule is a procedural requirement that during critical phases of flight (normally below 10,000 feet (3,050 m)), only activities required for the safe operation of the aircraft may be carried out by the flight crew, and all non-essential activities in the cockpit are forbidden. In the United States, the Federal Aviation Administration (FAA) imposed the rule in 1981, after reviewing a series of accidents that were caused by flight crews who were distracted from their flying duties by engaging in non-essential conversations and activities during critical parts of the flight.

One such accident was Eastern Air Lines Flight 212, which crashed just short of the runway at Charlotte/Douglas International Airport in 1974 while conducting an instrument approach in dense fog. The National Transportation Safety Board (NTSB) concluded that a probable cause of the accident was lack of altitude awareness due to distraction from idle chatter among the flight crew during the approach phase of the flight.

🔗 United States 🔗 Numismatics 🔗 Numismatics/American currency 🔗 United States/Massachusetts

BerkShares is a local currency that circulates in The Berkshires region of Massachusetts. It was launched on September 29, 2006 by BerkShares Inc., with research and development assistance from the Schumacher Center for a New Economics. The BerkShares website lists around 400 businesses in Berkshire County that accept the currency. Since launch, over 10 million BerkShares have been issued from participating branch offices of local banks (as of February 2020, 9 branches of 3 different banks). The bills were designed by John Isaacs and were printed by Excelsior Printing on special paper with incorporated security features from Crane & Co.. BerkShares are pegged with an exchange rate to the US dollar, but the Schumacher Center has discussed the possibility of pegging its value to a basket of local goods in order to insulate the local economy against volatility in the US economy.

🔗 Computing 🔗 Computing/Software 🔗 Computing/Amiga 🔗 Project-independent assessment

Amiga Unix (informally known as Amix) is a discontinued full port of AT&T Unix System V Release 4 operating system developed by Commodore-Amiga, Inc. in 1990 for the Amiga computer family as an alternative to AmigaOS, which shipped by default. Bundled with the Amiga 3000UX, Commodore's Unix was one of the first ports of SVR4 to the 68k architecture. The Amiga A3000UX model even got the attention of Sun Microsystems, though ultimately nothing came of it.

Unlike Apple's A/UX, Amiga Unix contained no compatibility layer to allow AmigaOS applications to run under Unix. With few native applications available to take advantage of the Amiga's significant multimedia capabilities, it failed to find a niche in the quite-competitive Unix workstation market of the early 1990s. The A3000UX's price tag of $4,998 (equivalent to $9,382 in 2019) was also not very attractive compared to other Unix workstations at the time, such as the NeXTstation ($5,000 for a base system, with a full API and many times the number of applications available), the SGI Indigo (starting at $8,000), or the Personal DECstation 5000 Model 25 (starting at $5,000). Sun, HP, and IBM had similarly priced systems. The A3000UX's 68030 was noticeably underpowered compared to most of its RISC-based competitors.

Unlike typical commercial Unix distributions of the time, Amiga Unix included the source code to the vendor-specific enhancements and platform-dependent device drivers (essentially any part that wasn't owned by AT&T), allowing interested users to study or enhance those parts of the system. However this source code was subject to the same license terms as the binary part of the system – it was not free software. Amiga Unix also incorporated and depended upon many open source components, such as the GNU C Compiler and X Window System, and included their source code.

Like many other proprietary Unix variants with small market shares, Amiga Unix vanished into the mists of computer history when its vendor, Commodore, went out of business. Today, Unix-like operating systems such as Minix, NetBSD, and Linux are available for the Amiga platform.

🔗 Computing 🔗 Telecommunications 🔗 Lists

This list ranks the countries of the world by the number of mobile phone numbers in use. Note that it is not the number of phone devices that are being given here, but the number of phone numbers in a country. In some countries, one person might have two mobile phones. Also, some mobile phone numbers may be used by machines as a modem (examples: intrusion detection systems, home automation, leak detection).

🔗 Computing 🔗 Computing/Computer hardware

The Dadda multiplier is a hardware binary multiplier design invented by computer scientist Luigi Dadda in 1965. It uses a selection of full and half adders to sum the partial products in stages (the Dadda tree or Dadda reduction) until two numbers are left. The design is similar to the Wallace multiplier, but the different reduction tree reduces the required number of gates (for all but the smallest operand sizes) and makes it slightly faster (for all operand sizes).

Dadda and Wallace multipliers have the same three steps for two bit strings ${\displaystyle w_{1}}$ and ${\displaystyle w_{2}}$ of lengths ${\displaystyle \ell _{1}}$ and ${\displaystyle \ell _{2}}$ respectively:

1. Multiply (logical AND) each bit of ${\displaystyle w_{1}}$, by each bit of ${\displaystyle w_{2}}$, yielding ${\displaystyle \ell _{1}\cdot \ell _{2}}$ results, grouped by weight in columns
2. Reduce the number of partial products by stages of full and half adders until we are left with at most two bits of each weight.
3. Add the final result with a conventional adder.

As with the Wallace multiplier, the multiplication products of the first step carry different weights reflecting the magnitude of the original bit values in the multiplication. For example, the product of bits ${\displaystyle a_{n}b_{m}}$ has weight ${\displaystyle n+m}$.

Unlike Wallace multipliers that reduce as much as possible on each layer, Dadda multipliers attempt to minimize the number of gates used, as well as input/output delay. Because of this, Dadda multipliers have a less expensive reduction phase, but the final numbers may be a few bits longer, thus requiring slightly bigger adders.

🔗 Germany 🔗 Skepticism 🔗 Paranormal

An April 1561 broadsheet by Hans Glaser described a mass sighting of celestial phenomena or unidentified flying objects (UFO) above Nuremberg (then a Free Imperial City of the Holy Roman Empire). Ufologists have speculated that these phenomena may have been extraterrestrial spacecraft. Skeptics assert that the phenomenon was likely to have been another atmospheric phenomenon, such as a sun dog, although the print doesn't fit the usual classic description of the phenomena.

🔗 Human rights 🔗 Discrimination 🔗 Poland 🔗 Disability 🔗 Hungary 🔗 South Africa

"Nothing about us without us" (Latin: Nihil de nobis, sine nobis) is a slogan used to communicate the idea that no policy should be decided by any representative without the full and direct participation of members of the group(s) affected by that policy. In its modern form, this often involves national, ethnic, disability-based, or other groups that are often marginalized from political, social, and economic opportunities.

The East German balloon escape occurred on 16 September 1979, when eight people in two families escaped the Eastern Bloc country of East Germany by crossing the border to the Western Bloc's West Germany in a homemade hot air balloon at around 2:00 a.m. The escape plot was carried out over one and a half years, including a previously unsuccessful attempt, three different balloons, and various modifications. One failed crossing alerted the government to the plot, but the police were not able to identify the suspects before their flight to the West.