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🔗 Computing 🔗 Michigan

The Michigan Terminal System (MTS) is one of the first time-sharing computer operating systems. Developed in 1967 at the University of Michigan for use on IBM S/360-67, S/370 and compatible mainframe computers, it was developed and used by a consortium of eight universities in the United States, Canada, and the United Kingdom over a period of 33 years (1967 to 1999).

🔗 Indigenous peoples of the Americas 🔗 Peru 🔗 Argentina

The Inca road system (often spelled Inka road system and known as Qhapaq Ñan meaning "royal road" in Quechua) was the most extensive and advanced transportation system in pre-Columbian South America. It was at least 40,000 kilometres (25,000 mi) long. The construction of the roads required a large expenditure of time and effort.

The network was composed of formal roads carefully planned, engineered, built, marked and maintained; paved where necessary, with stairways to gain elevation, bridges and accessory constructions such as retaining walls, and water drainage system. It was based on two north-south roads: one along the coast and the second and most important inland and up the mountains, both with numerous branches. It can be directly compared with the road network built during the Roman Empire, although the Inka road system was built one thousand years later. The road system allowed for the transfer of information, goods, soldiers and persons, without the use of wheels, within the Tawantinsuyu or Inka Empire throughout a territory with an extension was almost 2,000,000 km² (770,000 sq mi) and inhabited by about 12 million people.

The roads were bordered, at intervals, with buildings to allow the most effective usage: at short distance there were relay stations for chasquis, the running messengers; at a one-day walking interval tambos allowed support to the road users and the flocks of carrying llamas. Administrative centers with warehouses for re-distribution of goods were found along the roads. Towards the boundaries of the Inka Empire and in new conquered areas pukaras (fortresses) were found.

Part of the road network was built by cultures that precede the Inka Empire, notably the Wari culture in the northern central Peru and the Tiwanaku culture in Bolivia. Different organizations such as UNESCO and IUCN have been working to protect the network in collaboration with the governments and communities of the six countries (Colombia, Ecuador, Peru, Bolivia, Chile and Argentina) through which the Great Inka Road passes.

In modern times the roads see heavy use from tourism, such as the Inca Trail to Machu Picchu, well known by trekkers, connecting Ollantaytambo with Machu Picchu.

🔗 Biography 🔗 Computing 🔗 Business 🔗 Biography/science and academia 🔗 New York (state) 🔗 Criminal Biography 🔗 Computing/Computer Security 🔗 New Jersey 🔗 New York (state)/Cornell University 🔗 Computing/Networking

Robert Tappan Morris (born November 8, 1965) is an American computer scientist and entrepreneur. He is best known for creating the Morris worm in 1988, considered the first computer worm on the Internet.

Morris was prosecuted for releasing the worm, and became the first person convicted under the then-new Computer Fraud and Abuse Act. He went on to co-found the online store Viaweb, one of the first web-based applications, and later the funding firm Y Combinator—both with Paul Graham.

He later joined the faculty in the department of Electrical Engineering and Computer Science at the Massachusetts Institute of Technology, where he received tenure in 2006. He was elected to the National Academy of Engineering in 2019.

🔗 United States 🔗 Mathematics 🔗 Education 🔗 United States/Massachusetts 🔗 Higher Education

Math 55 is a two-semester long first-year undergraduate mathematics course at Harvard University, founded by Lynn Loomis and Shlomo Sternberg. The official titles of the course are Honors Abstract Algebra (Math 55a) and Honors Real and Complex Analysis (Math 55b). Previously, the official title was Honors Advanced Calculus and Linear Algebra.

🔗 Food and drink 🔗 Trains 🔗 Finland 🔗 Trains/Streetcars 🔗 Food and drink/Pubs

SpåraKoff is a HM V type tram converted into a mobile bar in Helsinki, Finland. Known as the pub tram, the vehicle does circular tours of downtown Helsinki picking up passengers for a fee during summer months. It is operated jointly by Sinebrychoff, HOK-Elanto (part of the S Group), and Helsinki City Transport.

The pub tram is immediately distinguishable in the Helsinki traffic by its vivid red colour (as opposed to the normal colours, green and cream, used on the Helsinki tram network of the Helsinki City Transport), and by the destination board that reads "PUB".

It is one of the four HM V trams that remain operational in Helsinki. Two of them are museum trams, and one is used as a non-passenger carrying advertisement tram.

🔗 Environment 🔗 Economics

In economics, the Jevons paradox (; sometimes Jevons effect) occurs when technological progress or government policy increases the efficiency with which a resource is used (reducing the amount necessary for any one use), but the rate of consumption of that resource rises due to increasing demand. The Jevons paradox is perhaps the most widely known paradox in environmental economics. However, governments and environmentalists generally assume that efficiency gains will lower resource consumption, ignoring the possibility of the paradox arising.

In 1865, the English economist William Stanley Jevons observed that technological improvements that increased the efficiency of coal-use led to the increased consumption of coal in a wide range of industries. He argued that, contrary to common intuition, technological progress could not be relied upon to reduce fuel consumption.

The issue has been re-examined by modern economists studying consumption rebound effects from improved energy efficiency. In addition to reducing the amount needed for a given use, improved efficiency also lowers the relative cost of using a resource, which increases the quantity demanded. This counteracts (to some extent) the reduction in use from improved efficiency. Additionally, improved efficiency increases real incomes and accelerates economic growth, further increasing the demand for resources. The Jevons paradox occurs when the effect from increased demand predominates, and improved efficiency increases the speed at which resources are used.

Considerable debate exists about the size of the rebound in energy efficiency and the relevance of the Jevons paradox to energy conservation. Some dismiss the paradox, while others worry that it may be self-defeating to pursue sustainability by increasing energy efficiency. Some environmental economists have proposed that efficiency gains be coupled with conservation policies that keep the cost of use the same (or higher) to avoid the Jevons paradox. Conservation policies that increase cost of use (such as cap and trade or green taxes) can be used to control the rebound effect.

🔗 Psychology

A cognitive distortion is an exaggerated or irrational thought pattern involved in the onset and perpetuation of psychopathological states, especially those more influenced by psychosocial factors, such as depression and anxiety. Psychiatrist Aaron T. Beck laid the groundwork for the study of these distortions, and his student David D. Burns continued research on the topic. Burns, in The Feeling Good Handbook (1989), described personal and professional anecdotes related to cognitive distortions and their elimination.

Cognitive distortions are thoughts that cause individuals to perceive reality inaccurately. According to the cognitive model of Beck, a negative outlook on reality, sometimes called negative schemas (or schemata), is a factor in symptoms of emotional dysfunction and poorer subjective well-being. Specifically, negative thinking patterns reinforce negative emotions and thoughts. During difficult circumstances, these distorted thoughts can contribute to an overall negative outlook on the world and a depressive or anxious mental state.

Challenging and changing cognitive distortions is a key element of cognitive behavioral therapy (CBT).

🔗 Africa 🔗 Photography 🔗 Africa/South Sudan

The Vulture and the Little Girl, also known as The Struggling Girl, is a photograph by Kevin Carter which first appeared in The New York Times on 26 March 1993. It is a photograph of a frail famine-stricken boy, initially believed to be a girl, who had collapsed in the foreground with a hooded vulture eyeing him from nearby. The child was reported to be attempting to reach a United Nations feeding centre about a half mile away in Ayod, Sudan (now South Sudan), in March 1993, and to have survived the incident. The picture won the Pulitzer Prize for Feature Photography award in 1994. Carter took his own life four months after winning the prize.

🔗 Computer graphics

Pixel-art scaling algorithms are graphical filters that are often used in video game console emulators to enhance hand-drawn 2D pixel art graphics. The re-scaling of pixel art is a specialist sub-field of image rescaling.

As pixel-art graphics are usually in very low resolutions, they rely on careful placing of individual pixels, often with a limited palette of colors. This results in graphics that rely on a high amount of stylized visual cues to define complex shapes with very little resolution, down to individual pixels. This makes image scaling of pixel art a particularly difficult problem.

A number of specialized algorithms have been developed to handle pixel-art graphics, as the traditional scaling algorithms do not take such perceptual cues into account.

Since a typical application of this technology is improving the appearance of fourth-generation and earlier video games on arcade and console emulators, many are designed to run in real time for sufficiently small input images at 60 frames per second. This places constraints on the type of programming techniques that can be used for this sort of real-time processing. Many work only on specific scale factors: 2× is the most common, with 3×, 4×, 5× and 6× also present.

🔗 Cryptography 🔗 Cryptography/Computer science

PGPfone was a secure voice telephony system developed by Philip Zimmermann in 1995. The PGPfone protocol had little in common with Zimmermann's popular PGP email encryption package, except for the use of the name. It used ephemeral Diffie-Hellman protocol to establish a session key, which was then used to encrypt the stream of voice packets. The two parties compared a short authentication string to detect a Man-in-the-middle attack, which is the most common method of wiretapping secure phones of this type. PGPfone could be used point-to-point (with two modems) over the public switched telephone network, or over the Internet as an early Voice over IP system.

In 1996, there were no protocol standards for Voice over IP. Ten years later, Zimmermann released the successor to PGPfone, Zfone and ZRTP, a newer and secure VoIP protocol based on modern VoIP standards. Zfone builds on the ideas of PGPfone.

According to the MIT PGPfone web page, "MIT is no longer distributing PGPfone. Given that the software has not been maintained since 1997, we doubt it would run on most modern systems."