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Topic Review
Photonic Laser Thruster
A photonic laser thruster (PLT) is an amplified photonic propulsion thruster for space propulsion that works on the principle of a photon-pushed sail, generating thrust directly from the momentum of a photon from a laser reflected from a mirror. The thruster, invented by Young K. Bae differs from other solar sail and laser propulsion thrusters in that an amplification process is used, in which the incident beam is re-used by being reflected by a stationary mirror, with an amplification stage at each reflection. Because of the recycling of energy, the photonic laser thruster has been demonstrated to be more energy efficient than other laser-pushed sail concepts. The near-term usage of the photonic laser thruster the earth-orbit applications include propellant-free and thrust-plume-contamination-free spacecraft maneuvering for precision formation flying, large optical and RF synthetic aperture construction, and stationkeeping. The usage of the photonic laser thruster for main space propulsion would require scaling-up of the laser power and controlling laser diffraction over interplanetary and interstellar distances. Photonic laser thrusters have a very high specific impulse, and can permit spacecraft to reach much higher speeds that approach a fraction of the light speed, unlike conventional rockets, which are limited by the Tsiolkovsky rocket equation.
  • 2.2K
  • 01 Nov 2022
Topic Review
Battery Swapping Stations for Electric Vehicles
Battery Swapping Stations (BSS), refers to the rapid recovery of electric vehicle energy by replacing batteries when the electric vehicle energy is about to run out.  Figure 1 shows the structure of BSS. The Electric vehicle users only own cars and rent batteries from service operators, thus greatly reducing the purchase cost of electric vehicles and solving the problem of long charging times.
  • 2.1K
  • 19 Apr 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).
  • 2.1K
  • 04 Nov 2022
Topic Review
Fiat CR.42
The Fiat CR.42 Falco ("Falcon", plural: Falchi) was a single-seat sesquiplane fighter developed and produced by Italian aircraft manufacturer Fiat Aviazione. It served primarily in Italy's Regia Aeronautica both before and during the Second World War. The CR.42 was an evolutionary design of Fiat’s earlier CR.32 fighter, featuring a more powerful supercharged Fiat A.74R1C.38 air-cooled radial engine and aerodynamic improvements to its relatively clean exterior surfaces. The aircraft proved to be relatively agile in flight, a factor that had been attributed to its very low wing loading and a sometimes decisive tactical advantage. RAF Intelligence praised its exceptional maneuverability, further noting that "the plane was immensely strong", though it was technically outclassed by faster, more heavily armed monoplanes. While primarily used as a fighter, various other roles were adopted for some variants of the type, such as the CR.42CN dedicated night fighter model, the CR.42AS ground attack aircraft, and the CR.42B Biposto twin-seat trainer aircraft. During May 1939, the CR.42 entered service with the Regia Aeronautica; it was the last of the Fiat biplane fighters to enter front line service. By 10 June 1940, the date when Italy entered the Second World War, roughly 300 of the type had been delivered, which were initially tasked with defending Italy's cities and key military installations. By the end of 1940, the Falco had been involved in combat on various fronts, including the Battle of France, the Battle of Britain, Malta, North Africa, and Greece. By the end of the war, Italian CR.42s had been used on further fronts, including Iraq, the Eastern Front and the Italian mainland. Following the signing of the Italian armistice with the Allies on 8 September 1943, the type was primarily relegated to use as a trainer by the Italian Co-Belligerent Air Force , while some Italian CR.42s were seized by the Germans and used by the Luftwaffe to perform ground attack missions. In addition to its service in Italy, the CR.42 was produced and entered service in smaller numbers with the air forces of several nations, including Belgium, Sweden and Hungary. By the end of production, in excess of 1,800 CR.42s has been constructed, making it the most numerous Italian aircraft to be used during the Second World War. Aviation author Przemyslaw Skulski has claimed that the fighter had performed at its best during its service with the Hungarian Air Force, specifically during its deployment against Soviet forces on the Eastern Front of the war, where it reportedly achieved a kill to loss ratio of 12 to 1.
  • 2.1K
  • 18 Nov 2022
Topic Review
DRDO Rustom
The DRDO Rustom (English: Warrior) is a Medium Altitude Long Endurance unmanned air vehicle (UAV) being developed by Defence Research and Development Organisation for the three services, Indian Army, Indian Navy and the Indian Air Force of the Indian Armed Forces. Rustom is derived from the NAL's LCRA (Light Canard Research Aircraft) developed by a team under the leadership of late Prof Rustom Damania in the 1980s. The UAV will have structural changes and a new engine. Rustom will replace/supplement the Heron UAVs in service with the Indian armed forces.
  • 2.1K
  • 02 Nov 2022
Topic Review
List of German Aircraft Projects, 1939–45
The aircraft in this list include prototype versions of aircraft used by the German Luftwaffe during World War II and unfinished wartime experimental programmes. In the former, development can stretch back to the 1920s and in the latter the project must have started between 1939-1945.
  • 2.1K
  • 14 Oct 2022
Topic Review
NEC Engineering and Construction Contract
The New Engineering Contract (NEC), or NEC Engineering and Construction Contract, is a formalised system created by the UK Institution of Civil Engineers that guides the drafting of documents on civil engineering and construction projects for the purpose of obtaining tenders, awarding and administering contracts. As such they legally define the responsibilities and duties of Employers (who commission work) and Contractors (who carry out work) in the Works Information. The contract consists of two key parts the Contract Data part one (Data provided by the Employer) and Contract Data part two (Data provided by the Contractor). Several approaches are included making it a family of options. It is used in the UK and internationally in countries including New Zealand, Australia , Hong Kong and South Africa . There have been four editions, the first in 1993, the second in 1995, the third in 2005 and the most recent in 2017. The NEC3 was launched in 2005 and it was amended in April 2013. NEC4 was announced in March 2017 and has been available since June 2017. This new edition reflects procurement and project management developments and emerging best practice, with improvements in flexibility, clarity and the ease of administration. It also introduces two new contracts: NEC4 Design, Build and Operate (DBO) and NEC4 Alliance Contract (ALC).
  • 2.1K
  • 28 Sep 2022
Topic Review
Autonomous Vehicle Guideline for Public Road-Testing Sustainability
Numerous countries have developed guidelines for public road testing, but those rules are not uniform, and discrepancies occur between nations. Issues such as vehicular safety, registrations, authority, insurance, cybersecurity, and infrastructures weigh differently in each country. Rather than relying on a single national standard as a reference, an amalgam of guidelines from different countries allows a more holistic and measured view of AV testing practices. Synthesizing these diverse national regulations into global guidelines would promote the safety and sustainability of autonomous vehicle testing and benefit all parties interested in autonomous vehicles.
  • 2.1K
  • 17 Feb 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.
  • 2.0K
  • 14 Oct 2022
Topic Review
Bayraktar Tactical UAS
The Bayraktar Tactical UAS is a surveillance and reconnaissance unmanned aerial vehicle (UAV) initially developed for the Turkish Armed Forces. It is developed by the Kale-Baykar, a joint venture between the Kale Group and Baykar Technologies. In 2014, Bayraktar held the national endurance and altitude record for Turkey's unmanned aerial vehicles (UAV). It set a record for autonomous flight endurance when it flew 24 hours and 34 minutes at 18,000 feet on 5 August 2014. It furthermore recorded highest altitude of 27,030 feet on its flight on 14 June 2014 with full payload. Bayraktar TB2 successfully demonstrated firing of ROKETSAN MAM-L Smart Micro Munition with 100% accuracy in December 2015. While the Turkish Armed Forces describes Bayraktar as "Tactical UAV Class" to prevent it from being a competitor to the TAI Anka UAV, international standards would classify it as a medium-altitude long-endurance UAV. With its 650 kg MTOW and 12 meters wingspan platform powered by an internal combustion engine, Bayraktar is capable of flying at 22,500 feet and loitering for more than 24 hours.
  • 2.0K
  • 24 Oct 2022
Topic Review
Jeep Renegade (BU)
The Jeep Renegade (BU/520) is a subcompact crossover SUV (B-segment) produced by FCA US under their Jeep marque. It was first shown to the public in March 2014 at the Geneva Motor Show and production started in late August of that year. Standard Renegade models come with front-wheel drive. The vehicle offers the four-wheel drive systems Active Drive I and Active Drive Low, both of which are paired with Jeep's Selec-Terrain System.
  • 2.0K
  • 15 Nov 2022
Topic Review
Fire Engine
A fire engine, also known in some places as a fire truck or fire lorry, is a road vehicle (usually a truck) that functions as a firefighting apparatus. The primary purposes of a fire engine include transporting firefighters to an incident as well as carrying equipment for firefighting operations. Some fire engines have specialised functions, such as wildfire suppression and aircraft rescue and firefighting, and may also carry equipment for technical rescue. Many fire engines are based on commercial vehicle chassis that are further upgraded and customised for firefighting requirements. They are normally fitted with sirens and emergency vehicle lighting, as well as communication equipment such as two-way radios and mobile computer technology. The terms fire engine and fire truck are often used interchangeably to a broad range of vehicles involved in firefighting; however, in some fire departments they refer to separate and specific types of vehicle.
  • 2.0K
  • 12 Oct 2022
Topic Review
List of AEW&C Aircraft Operators
Airborne early warning and control (AEW&C) aircraft are airborne radar systems designed to detect and track aircraft, missiles, ships and vehicles and provide command and control to direct friendly forces. Some operators, such as the Royal Air Force refer to such aircraft as Airborne early warning (AEW), while others reserve the shorter name for AEW aircraft lacking command and control facilities.
  • 2.0K
  • 03 Nov 2022
Topic Review
Panzer I Variants
The Panzerkampfwagen I (PzKpfW I) was a light tank produced in Germany in the 1930s. The Panzer I was built in several variants and was the basis for a number of variants listed below.
  • 1.9K
  • 31 Oct 2022
Topic Review
Shipunov 2A42
The Shipunov 2A42 is a Soviet/Russian 30 mm autocannon. It is built by the Tulamashzavod Joint Stock Company.
  • 1.9K
  • 11 Oct 2022
Topic Review
Lugnut (Transformers)
Lugnut is the name of several fictional characters from the Transformers universe. Both are Decepticon jets who are loyal to Megatron.
  • 1.9K
  • 18 Nov 2022
Topic Review
Solar Radiation Management
Solar radiation management (SRM) proposals are a type of climate engineering which would seek to reflect sunlight and thus reduce global warming. Proposed methods include increasing the planetary albedo, for example using stratospheric sulfate aerosols. Restorative methods have been proposed regarding the protection of natural heat reflectors like sea ice, snow and glaciers with engineering projects. Their principal advantages as an approach to climate engineering is the speed with which they can be deployed and become fully active, their potential low financial cost, and the reversibility of their direct climatic effects. Solar radiation management projects could serve as a temporary response while levels of greenhouse gases can be brought under control by mitigation and greenhouse gas removal techniques. They would not reduce greenhouse gas concentrations in the atmosphere, and thus do not address problems such as ocean acidification caused by excess carbon dioxide (CO2).
  • 1.9K
  • 24 Nov 2022
Topic Review
Breguet 14
The Breguet 14 was a French biplane bomber and reconnaissance aircraft of the First World War. It was built in very large numbers and production continued for many years after the end of the war. Apart from its widespread usage, the Breguet 14 is known for being the first mass-produced aircraft to use large amounts of metal, rather than wood, in its structure. This allowed the airframe to be lighter than a wooden airframe of the same strength, in turn making the aircraft relatively fast and agile for its size; in combat situations, it was able to outrun many of the contemporary fighters of the day. The Breguet 14's strong construction allowed it to sustain considerable damage, in addition to being easy to handle and possessing favourable performance. The type has often been considered to have been one of the best aircraft of the war.
  • 1.9K
  • 14 Nov 2022
Topic Review
Regulation of Unmanned Aerial Vehicles
The use of unmanned aerial vehicles (UAVs) is generally regulated by the national aviation authority of the country.
  • 1.9K
  • 31 Oct 2022
Topic Review
Hydraulics
Hydraulics (from Greek: Υδραυλική) is a technology and applied science using engineering, chemistry, and other sciences involving the mechanical properties and use of liquids. At a very basic level, hydraulics is the liquid counterpart of pneumatics, which concerns gases. Fluid mechanics provides the theoretical foundation for hydraulics, which focuses on the applied engineering using the properties of fluids. In its fluid power applications, hydraulics is used for the generation, control, and transmission of power by the use of pressurized liquids. Hydraulic topics range through some parts of science and most of engineering modules, and cover concepts such as pipe flow, dam design, fluidics and fluid control circuitry. The principles of hydraulics are in use naturally in the human body within the vascular system and erectile tissue. Free surface hydraulics is the branch of hydraulics dealing with free surface flow, such as occurring in rivers, canals, lakes, estuaries and seas. Its sub-field open-channel flow studies the flow in open channels. The word "hydraulics" originates from the Greek word ὑδραυλικός (hydraulikos) which in turn originates from ὕδωρ (hydor, Greek for water) and αὐλός (aulos, meaning pipe).
  • 1.9K
  • 28 Nov 2022
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