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🔗 Software 🔗 Software/Computing

Waterfox is an open-source web browser for x64, ARM64, and PPC64LE systems. It is intended to be speedy and ethical, and maintain support for legacy extensions dropped by Firefox, from which it is forked. There are official releases for Windows (including a portable version), Mac OS, Linux and Android.

Waterfox is based on Firefox and is compiled using various compilers and using Intel's Math Kernel Library, Streaming SIMD Extensions 3 and Advanced Vector Extensions. Linux builds are built with Clang on all architectures other than PPC64LE. Waterfox is continuing to support the long-standing XUL and XPCOM add-on capability that Firefox removed in version 57.

🔗 Linguistics

Initial-stress derivation is a phonological process in English that moves stress to the first syllable of verbs when they are used as nouns or adjectives. (This is an example of a suprafix.) This process can be found in the case of several dozen verb-noun and verb-adjective pairs and is gradually becoming more standardized in some English dialects, but it is not present in all. The list of affected words differs from area to area, and often depends on whether a word is used metaphorically or not. At least 170 verb-noun or verb-adjective pairs exist. Some examples are:

• record.

as a verb, "Remember to recórd the show!".

as a noun, "I'll keep a récord of that request."

• permit.

as a verb, "I won't permít that."

as a noun, "We already have a pérmit."

🔗 Psychology

An autostereogram is a single-image stereogram (SIS), designed to create the visual illusion of a three-dimensional (3D) scene from a two-dimensional image. In order to perceive 3D shapes in these autostereograms, one must overcome the normally automatic coordination between accommodation (focus) and horizontal vergence (angle of one's eyes). The illusion is one of depth perception and involves stereopsis: depth perception arising from the different perspective each eye has of a three-dimensional scene, called binocular parallax.

The simplest type of autostereogram consists of horizontally repeating patterns (often separate images) and is known as a wallpaper autostereogram. When viewed with proper convergence, the repeating patterns appear to float above or below the background. The well-known Magic Eye books feature another type of autostereogram called a random dot autostereogram. One such autostereogram is illustrated above right. In this type of autostereogram, every pixel in the image is computed from a pattern strip and a depth map. A hidden 3D scene emerges when the image is viewed with the correct convergence.

Autostereograms are similar to normal stereograms except they are viewed without a stereoscope. A stereoscope presents 2D images of the same object from slightly different angles to the left eye and the right eye, allowing us to reconstruct the original object via binocular disparity. When viewed with the proper vergence, an autostereogram does the same, the binocular disparity existing in adjacent parts of the repeating 2D patterns.

There are two ways an autostereogram can be viewed: wall-eyed and cross-eyed. Most autostereograms (including those in this article) are designed to be viewed in only one way, which is usually wall-eyed. Wall-eyed viewing requires that the two eyes adopt a relatively parallel angle, while cross-eyed viewing requires a relatively convergent angle. An image designed for wall-eyed viewing if viewed correctly will appear to pop out of the background, while if viewed cross-eyed it will instead appear as a cut-out behind the background and may be difficult to bring entirely into focus.

🔗 Trains

The symmetry minute is a significant time point in the clock face timetables used by many public transport operators. At this point in the cycle, a train in a clock-face timetable meets its counterpart travelling in the opposite direction on the same line. If this crossing time is constant across a network, connecting times between lines are kept consistent in both directions.

At the symmetry time, the timetable is mirrored in both directions. At the ends of the line, the center of the turnaround time coincides with the symmetry minute. The distance between two consecutive symmetry times is equal to half the cycle time, so on an hourly schedule, opposite trains on the same line cross every 30 minutes. On a two-hour cycle, there is a symmetry time every hour.

In principle, a train-encounter can be set at any time. However, at the transition between two networks or lines, it is expedient to set uniform symmetry minutes, to create a symmetrical connection relation. For the long-distance cycle systems of ÖBB and SBB, the Forschungsgesellschaft für Straßen- und Verkehrswesen für Deutschland (Research Association for Roads and Traffic for Germany) recommends minute 58, so a four-minute minimum connecting time results in a departure at minute 0. Meanwhile, most railways in Central Europe and a number of other transport operators have established the symmetry minute 58½, for a three-minute hold time before a departure at minute 0. Shorter cycles have additional symmetry minutes, shifted by half the cycle time. So an hourly cycle has symmetries at minutes 28½ and 58½, a 30-minute cycle has symmetries at minutes 13½, 28½, 43½ and 58½, and so on.

The following table shows the departure times in opposite directions for an hourly cycle, using the 58½ symmetry minute (the most common in Central Europe). The other departure times for shorter cycles can be calculated from it. The last line gives the meeting times.

🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Palestine 🔗 Western Asia 🔗 Military history/Middle Eastern military history 🔗 Western Asia/Kuwait

The Highway of Death (Arabic: طريق الموت ṭarīq al-mawt) is a six-lane highway between Kuwait and Iraq, officially known as Highway 80. It runs from Kuwait City to the border town of Safwan in Iraq and then on to the Iraqi city of Basra. The road was used by Iraqi armored divisions for the 1990 invasion of Kuwait. It was repaired after the Gulf War and used by U.S. and British forces in the initial stages of the 2003 invasion of Iraq.

During the American-led coalition offensive in the Persian Gulf War, American, Canadian, British and French aircraft and ground forces attacked retreating Iraqi military personnel attempting to leave Kuwait on the night of February 26–27, 1991, resulting in the destruction of hundreds of vehicles and the deaths of many of their occupants. Between 1,400 and 2,000 vehicles were hit or abandoned on the main Highway 80 north of Al Jahra.

The scenes of devastation on the road are some of the most recognizable images of the war, and it has been suggested that they were a factor in President George H. W. Bush's decision to declare a cessation of hostilities the next day. Many Iraqi forces successfully escaped across the Euphrates river, and the U.S. Defense Intelligence Agency estimated that upwards of 70,000 to 80,000 troops from defeated divisions in Kuwait might have fled into Basra, evading capture.

🔗 Computing

Anton is a massively parallel supercomputer designed and built by D. E. Shaw Research in New York, first running in 2008. It is a special-purpose system for molecular dynamics (MD) simulations of proteins and other biological macromolecules. An Anton machine consists of a substantial number of application-specific integrated circuits (ASICs), interconnected by a specialized high-speed, three-dimensional torus network.

Unlike earlier special-purpose systems for MD simulations, such as MDGRAPE-3 developed by RIKEN in Japan, Anton runs its computations entirely on specialized ASICs, instead of dividing the computation between specialized ASICs and general-purpose host processors.

Each Anton ASIC contains two computational subsystems. Most of the calculation of electrostatic and van der Waals forces is performed by the high-throughput interaction subsystem (HTIS). This subsystem contains 32 deeply pipelined modules running at 800 MHz arranged much like a systolic array. The remaining calculations, including the bond forces and the fast Fourier transforms (used for long-range electrostatics), are performed by the flexible subsystem. This subsystem contains four general-purpose Tensilica cores (each with cache and scratchpad memory) and eight specialized but programmable SIMD cores called geometry cores. The flexible subsystem runs at 400 MHz.

Anton's network is a 3D torus and thus each chip has 6 inter-node links with a total in+out bandwidth of 607.2 Gbit/s. An inter-node link is composed of two equal one-way links (one traveling in each direction), with each one-way link having 50.6 Gbit/s of bandwidth. Each one-way link is composed of 11 lanes, where a lane is a differential pair of wires signaling at 4.6 Gbit/s. The per-hop latency in Anton's network is 50 ns. Each ASIC is also attached to its own DRAM bank, enabling large simulations.

The performance of a 512-node Anton machine is over 17,000 nanoseconds of simulated time per day for a protein-water system consisting of 23,558 atoms. In comparison, MD codes running on general-purpose parallel computers with hundreds or thousands of processor cores achieve simulation rates of up to a few hundred nanoseconds per day on the same chemical system. The first 512-node Anton machine became operational in October 2008. The multiple petaFLOP, distributed-computing project Folding@home has achieved similar aggregate ensemble simulation timescales, comparable to the total time of a single continuous simulation on Anton, specifically achieving the 1.5-millisecond range in January 2010.

The Anton supercomputer is named after Anton van Leeuwenhoek, who is often referred to as "the father of microscopy" because he built high-precision optical instruments and used them to visualize a wide variety of organisms and cell types for the first time.

The ANTON 2 machine with four 512 nodes and substantially increased speed and problem size has been described.

The National Institutes of Health have supported an ANTON for the biomedical research community at the Pittsburgh Supercomputing Center, Carnegie-Mellon University, and recently approved support of an ANTON 2 there.

🔗 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".

🔗 Computing 🔗 Computer science 🔗 Brands

Cell is a multi-core microprocessor microarchitecture that combines a general-purpose PowerPC core of modest performance with streamlined coprocessing elements which greatly accelerate multimedia and vector processing applications, as well as many other forms of dedicated computation.

It was developed by Sony, Toshiba, and IBM, an alliance known as "STI". The architectural design and first implementation were carried out at the STI Design Center in Austin, Texas over a four-year period beginning March 2001 on a budget reported by Sony as approaching US$400 million. Cell is shorthand for Cell Broadband Engine Architecture, commonly abbreviated CBEA in full or Cell BE in part.

The first major commercial application of Cell was in Sony's PlayStation 3 game console, released in 2006. In May 2008, the Cell-based IBM Roadrunner supercomputer became the first TOP500 LINPACK sustained 1.0 petaflops system. Mercury Computer Systems also developed designs based on the Cell.

The Cell architecture includes a memory coherence architecture that emphasizes power efficiency, prioritizes bandwidth over low latency, and favors peak computational throughput over simplicity of program code. For these reasons, Cell is widely regarded as a challenging environment for software development. IBM provides a Linux-based development platform to help developers program for Cell chips.

🔗 Energy

In utility-scale electricity generation, the duck curve is a graph of power production over the course of a day that shows the timing imbalance between peak demand and renewable energy production. The term was coined in 2012 by the California Independent System Operator.

🔗 Environment 🔗 Business 🔗 Politics 🔗 Sociology

In planning and policy, a wicked problem is a problem that is difficult or impossible to solve because of incomplete, contradictory, and changing requirements that are often difficult to recognize. It refers to an idea or problem that cannot be fixed, where there is no single solution to the problem; and "wicked" denotes resistance to resolution, rather than evil. Another definition is "a problem whose social complexity means that it has no determinable stopping point". Moreover, because of complex interdependencies, the effort to solve one aspect of a wicked problem may reveal or create other problems.

The phrase was originally used in social planning. Its modern sense was introduced in 1967 by C. West Churchman in a guest editorial Churchman wrote in the journal Management Science, responding to a previous use of the term by Horst Rittel. Churchman discussed the moral responsibility of operations research "to inform the manager in what respect our 'solutions' have failed to tame his wicked problems". Rittel and Melvin M. Webber formally described the concept of wicked problems in a 1973 treatise, contrasting "wicked" problems with relatively "tame", soluble problems in mathematics, chess, or puzzle solving.