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Topic Review
Semaphore Line
A semaphore telegraph is a system of conveying information by means of visual signals, using towers with pivoting shutters, also known as blades or paddles. Information is encoded by the position of the mechanical elements; it is read when the shutter is in a fixed position. The most widely used system was invented in 1792 in France by Claude Chappe, and was popular in the late eighteenth to early nineteenth centuries. Lines of relay towers with a semaphore rig at the top were built within line-of-sight of each other, at separations of 5 to 20 miles. Operators at each tower would watch the neighboring tower through a spyglass, and when the semaphore arms began to move spelling out a message. They would pass the message on to the next tower. This system was much faster than post riders for conveying a message over long distances, and also had cheaper long-term operating costs, once constructed. Semaphore lines were a precursor of the electrical telegraph, which would replace them half a century later, and would also be cheaper, faster, and more private. The line-of-sight distance between relay stations was limited by geography and weather, and prevented the optical telegraph from crossing wide expanses of water, unless a convenient island could be used for a relay station. Modern derivatives of the semaphore system include flag semaphore (a flag relay system) and the heliograph (optical telegraphy using mirror-directed sunlight reflections).
  • 1.9K
  • 20 Oct 2022
Topic Review
UAVs in the U.S. Military
As of January 2014, the U.S. military operates a large number of unmanned aerial systems (UAVs or Unmanned Air Vehicles): 7,362 RQ-11 Ravens; 990 AeroVironment Wasp IIIs; 1,137 AeroVironment RQ-20 Pumas; and 306 RQ-16 T-Hawk small UAS systems and 246 Predators and MQ-1C Grey Eagles; 126 MQ-9 Reapers; 491 RQ-7 Shadows; and 33 RQ-4 Global Hawk large systems. The military role of unmanned aircraft systems is growing at unprecedented rates. In 2005, tactical- and theater-level unmanned aircraft alone had flown over 100,000 flight hours in support of Operation Enduring Freedom and Operation Iraqi Freedom, in which they are organized under Task Force Liberty in Afghanistan and Task Force ODIN in Iraq. Rapid advances in technology are enabling more and more capability to be placed on smaller airframes, which is spurring a large increase in the number of Small Unmanned Aircraft Systems (SUAS) being deployed on the battlefield. The use of SUAS in combat is so new that no formal DoD wide reporting procedures have been established to track SUAS flight hours. As the capabilities grow for all types of UAS, nations continue to subsidize their research and development, leading to further advances and enabling them to perform a multitude of missions. UAS no longer only perform intelligence, surveillance, and reconnaissance missions, although this still remains their predominant type. Their roles have expanded to areas including electronic attack, drone strikes, suppression or destruction of enemy air defense, network node or communications relay, combat search and rescue, and derivations of these themes. These UAS range in cost from a few thousand dollars to tens of millions of dollars, with aircraft ranging from less than one pound to over 40,000 pounds.
  • 1.9K
  • 14 Oct 2022
Topic Review
ZIS-5 (Truck)
The ZIS-5 (Russian: ЗиС-5) was a 4x2 Soviet truck produced by Moscow ZIS factory from 1932 to 1948 (first one made at the end of 1930).
  • 1.9K
  • 04 Nov 2022
Biography
Shahid Khan
Shahid Khan (Urdu: شاہد خان‎; born July 18, 1950),[1][2] also known as Shad Khan, is a Pakistani-American billionaire businessman and philanthropist. He is the owner of the Jacksonville Jaguars of the National Football League (NFL) and Fulham F.C. of the English Premier League. Khan is also the owner of the automobile parts manufacturer Flex-N-Gate in Urbana, Illinois. Khan was feature
  • 1.9K
  • 30 Nov 2022
Topic Review
AI Public Datasets for Railway Applications
The aim of this entry is to review existing publicly available and open artificial intelligence (AI) oriented datasets in different domains and subdomains of the railway sector. The contribution of this paper is an overview of AI-oriented railway data published under Creative Commons (CC) or any other copyright type that entails public availability and freedom of use. These data are of great value for open research and publications related to the application of AI in the railway sector.
  • 1.9K
  • 09 Oct 2021
Topic Review
Strain Rate Sensitivity
Strain rate is a parameter related with dynamic loading phenomena, which are common in industrial applications.
  • 1.9K
  • 06 Sep 2021
Topic Review
Applications of Social Robotics
Social robots are being proposed in telepresence, medicine, education, entertainment, assistance, and other domains. Benefiting from their information acquisition and processing, and actuation capacities, social robots are conceived to either replace or assist humans in daily social interaction contexts.
  • 1.9K
  • 04 Aug 2022
Topic Review
Probabilistic Optimization Techniques in Smart Power System
Stochastic programming is used to solve optimization problems in which the majority of the parameters are probabilistic. Probabilistic optimization can make efficient use of information, both in terms of selecting evaluation points and the message they convey. It can handle many sorts of noise and adapts to various aspects of optimization issues. Unlike deterministic optimization, probabilistic optimization techniques discover the best solution for data with randomness.
  • 1.9K
  • 17 Feb 2022
Topic Review
Daihatsu Rocky
The Daihatsu Rocky (Japanese: ダイハツ・ロッキー, Daihatsu Rokkī) is an automobile nameplate used by Daihatsu for their lineup of SUVs. The nameplate was originally used as a ladder frame-based mini SUV that was sold in Japan and some international markets between 1989 and 2002. It was gradually replaced by the introduction of Terios in 1997. Beginning in 2019, the Rocky nameplate returned to Japan as a subcompact crossover SUV that replaces the Be‣go and is also rebadged and sold under Toyota brand as the Toyota Raize (Japanese: トヨタ・ライズ, Toyota Raizu).
  • 1.9K
  • 27 Oct 2022
Topic Review
Human Emotion Recognition
Automated emotion recognition (AEE) is important issue in the various field of activities, which uses human emotional reaction as a signal for marketing, technical equipment or human-robot interaction. Paper analyzes vast layer of scientific research and technical papers for sensor use analysis, where various methods implemented or researched. Paper cover few classes of sensors, using contactless methods, contact and skin-penetrating electrodes with for human emotion detection and measurement of their intensity. Result of performed analysis in this paper presented applicable methods for each type of emotions or their intensity and proposed their classification. Provided classification of emotion sensors revealed area of application and expected outcome from each method as well as noticed limitation of them. This paper should be interested for researchers, needed to use of human emotion evaluation and analysis, when there is a need to choose proper method for their purposes or find alternative decision.
  • 1.9K
  • 27 Jan 2021
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