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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).
  • 1.7K
  • 04 Nov 2022
Topic Review
Zipline (Drone Delivery)
Zipline is an American medical product delivery company that is headquartered in South San Francisco, California, and which designs, manufactures, and operates delivery drones. The company operates distribution centers in Rwanda, Ghana, and the US, with signed agreements to begin service in Japan , Nigeria, Cote d'Ivoire, and Kenya. As of December 2021, its drones have made over 225,000 commercial deliveries. The company's drones deliver whole blood, platelets, frozen plasma, and cryoprecipitate along with medical products including vaccines, infusions and routine medical commodities. As of September 2021, more than 75% of blood deliveries in Rwanda outside of Kigali use Zipline drones. In April 2019 in Ghana, the company began using drones to deliver vaccines, blood, and medicines. During the COVID-19 pandemic in 2020, the US Federal Aviation Administration (FAA) granted a Part 107 waiver to Zipline's partner organization Novant Health for the delivery of medical supplies and personal protective equipment (PPE) to medical facilities in North Carolina. Along with nine other drone delivery companies, the FAA selected Zipline to participate in a type certification program for delivery drones.
  • 3.9K
  • 06 Oct 2022
Topic Review
YSD-11 Class Seaplane Wrecking Derrick
YSD-11 Class Seaplane Wrecking Derrick is a class of US Navy derrick crane ship. While listed to service seaplanes the crane was able to lift small boats and large engines also. Hull classification symbol YSD is for Yard Seaplane Dirrick, Yard as in ship repair yard. YSD-11s were used to remove broken seaplanes from the water for repair or regular maintenance. The US had 2,661 Consolidated PBY Catalina built for the war, Canada built 620. Other seaplanes built in mass production were the 1,366 Martin PBM Mariner, 749 Short Sunderland and 345 Grumman G-21 Goose. The YSD-11 Class Derrick was built to support World War 2, having a displacement of 220 tons no load and 270 tons loaded. The YSD-11 Class had a length 104 feet; a beam of 31 feet and 2 inches; a draft of 4 feet. They had a top speed 10 knots, built with a steel hull. The ship had one American Hoist & Derrick model 685 rotating crane. The crane had a boom of 54 feet with a lifting capacity of 10 tons. The crane was powered by a 6-cylinder Cummins Diesel engine. The ship housed a crew of one Officer and 15 Enlisted men. The ships had a diving gear locker for the crew salvage work. For service power, the ship had two generators: one 30Kw Diesel engine to electric generator and one 20Kw Diesel Generator. Ship power was from two Superior model MRDB-8 200 HP Diesel engines with two propellers, 640shp. The YSD-11 Class Derricks were built by a number of United States shipyards, including Moore Equipment Company, Puget Sound Navy Yard, Charleston Navy Yard, Mare Island Naval Shipyard, Soule Steel Company, Pearl Harbor Navy Yard and Boston Navy Yard.
  • 503
  • 24 Oct 2022
Topic Review
Yandex Self-Driving Car
Yandex self-driving car (Yandex Self-Driving Group) is a robotaxi project of the Russian-based internet corporation Yandex. The first driverless prototype launched in May 2017. As of 2018, functional service was launched in Russia with prototypes also being tested in Israel and the US. In 2019, Yandex revealed autonomous delivery robots based on the same technology stack as the company's self-driving cars. Since 2020, autonomous robots have been delivering food, groceries and parcels in Russia and the USA. In 2020, the self-driving project was spun-off into a standalone company under the name of Yandex Self-Driving Group (Yandex SDG).
  • 1.2K
  • 27 Oct 2022
Topic Review
Wreckage (Transformers)
Wreckage is the name of three fictional characters from the Transformers series.
  • 351
  • 23 Nov 2022
Topic Review
World Bicycle Relief
World Bicycle Relief is an international, non-profit organization based in Chicago, IL that specializes in large-scale, comprehensive bicycle distribution programs to aid poverty relief in developing countries around the world. Their programs focus primarily on education, economic development, and health care. As of February 2020, World Bicycle Relief has distributed 500,000 bicycles in 21 countries and trained more than 2,300 bicycle mechanics in the developing world. Within their largest program, the Bicycles For Educational Empowerment program, nearly 70 percent of the student bicycles are designated for girl students.
  • 308
  • 14 Nov 2022
Topic Review
Working Bikes
Working Bikes is a not-for-profit tax-exempt 501(c)3 volunteer-driven organization based in Chicago, IL that aims to divert bicycles from the waste stream and put them to use in Chicago and abroad. It operates a warehouse, shipping center, repair shop and retail outlet from its location in the Pilsen neighborhood. Working Bikes mission is to provide bicycles to charity organizations in the Chicago area to benefit youth, transitioning homeless and refugees as well as to ship bicycles to the Gulf Coast and around the world. Each year Working Bikes aims to sell 2,000 refurbished bikes through its storefront and runs a repair shop to keep bikes in operation. It uses the proceeds from these activities to give away approximately 6,000 bikes per year. Since its inception, as cited within the Working Bikes 2018 Annual Report, "More than 70,000 bikes have been given new life across our region and the world".
  • 307
  • 03 Nov 2022
Topic Review
Work
In physics, work is the energy transferred to or from an object via the application of force along a displacement. In its simplest form, it is often represented as the product of force and displacement. A force is said to do positive work if (when applied) it has a component in the direction of the displacement of the point of application. A force does negative work if it has a component opposite to the direction of the displacement at the point of application of the force. For example, when a ball is held above the ground and then dropped, the work done by the gravitational force on the ball as it falls is equal to the weight of the ball (a force) multiplied by the distance to the ground (a displacement). When the force F is constant and the angle between the force and the displacement s is θ, then the work done is given by: [math]\displaystyle{ W = F s \cos{\theta} }[/math] Work is a scalar quantity, so it has only magnitude and no direction. Work transfers energy from one place to another, or one form to another. The SI unit of work is the joule (J), the same unit as for energy.
  • 1.1K
  • 25 Oct 2022
Topic Review
Woodward Effect
The Woodward effect, also referred to as a Mach effect, is part of a hypothesis proposed by James F. Woodward in 1990. The hypothesis states that transient mass fluctuations arise in any object that absorbs internal energy while undergoing a proper acceleration. Harnessing this effect could generate a reactionless thrust, which Woodward and others claim to measure in various experiments. Hypothetically, the Woodward effect would allow for field propulsion spacecraft engines that would not have to expel matter. Such a proposed engine is sometimes called a Mach effect thruster (MET) or a Mach Effect Gravitational Assist (MEGA) drive. So far, experimental results have not strongly supported this hypothesis, but experimental research on this effect, and its potential applications, continues. The Space Studies Institute was selected as part of NASA's Innovative Advanced Concepts program as a Phase I proposal in April 2017 for Mach Effect research. The year after, NASA awarded a NIAC Phase II grant to the SSI to further develop these propellantless thrusters. The effect is controversial within mainstream physics because the underlying model proposed for it appears to be faulty, resulting in violations of energy conservation as well as momentum conservation.
  • 2.3K
  • 16 Nov 2022
Topic Review
Wooden Boats of World War 2
Splinter fleet or Splinter navy was a nickname given to the wooden boats used in World War II. The boats served in many different roles during the war. These boats were built in small boatyards on the West coast and East coast, Great Lakes and the Gulf of Mexico. They could be built quickly, in just 60 to 120 days. Most of the boats were built by boatyards that already had the tools and knowledge from building yachts, sailboats and motor boats. Many were built by craftsmen in family-owned small businesses. Under the Emergency Shipbuilding Program and War Shipping Administration contracts went out to over fifty boatyards across the country. The boats were built for the US Navy, the, United States Army Air Forces , United States Coast Guard, and US Army. Some of the wooden boats went to Allied nations on the Lend-Lease program. In addition to new boat construction, some wooden boats built between 1910 and 1941 were acquired for the war effort, some used as-is and others converted for war use. Wooden boats have lighter weight and are easier to repair than steel hull boats. These wooden boats ranged from 19 to 200 feet in length. Some worked near shore and others working in the open ocean, called the Blue-water navy. The Splinter fleet is in contrast to the more common steel hull war ships and Merchant Marine ships. After the war, many of these boats were deemed not needed. Many were abandoned or destroyed, a few served in the Korean war and a few in the Vietnam War, some sold to private and some donated. During World War I there was a debate as to if wooden boats and ships should be used in war time. William Denman, President of the Emergency Fleet Corporation supported the building of wooden ships for the war and General Goethals disapproved. In the end, both men turned in their resignation over the heated debate. During World War II the situation was different. There was a shortage of steel and steel shipyards, so there was no debate about the need for a vast wooden fleet of boats and ships.
  • 2.9K
  • 14 Oct 2022
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