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Topic Review
Ground Based Strategic Deterrent
The Ground Based Strategic Deterrent (GBSD) is a future American land-based intercontinental ballistic missile system (ICBM) currently in the early stages of development. It is slated to replace the aging Minuteman III missiles, currently stationed in North Dakota, Wyoming, Montana, Nebraska and Colorado, from 2029 through 2075. In 2020, under the Trump administration, the Department of the Air Force gave the defense contractor, Northrop Grumman, a $13.3 billion sole-source contract for development of the GBSD after Boeing withdrew its proposal. Northrop Grumman's subcontractors on the GBSD include Lockheed Martin, General Dynamics, Bechtel, Honeywell, Aerojet Rocketdyne, Parsons, Textron and others.
  • 577
  • 28 Nov 2022
Topic Review
Nanosilica-toughened epoxy resins
Surface-modified silica nanoparticles are available as concentrates in epoxy resins inindustrial quantities for nearly 20 years. Meanwhile, they are used in many epoxy resin formulationsfor various applications like fiber-reinforced composites, adhesives or electronic components; even inspace vehicles like satellites. Some of the drawbacks of “classic” epoxy toughening using elastomersas a second phase, like lower modulus or a loss in strength can be compensated by using nanosilicatogether with such tougheners. Apparently, there exists a synergy as toughness and fatigueperformance are increased significantly. This work intends to provide an overview regarding thepossibilities of nanotoughening with silica, the industrial applications of such epoxy resin formulationsand the most recent research results. Furthermore an overview of other material improvements achieved by the modification of epoxy resins with nanosilica is given.
  • 575
  • 05 Jan 2021
Biography
Robert W. Farquhar
Robert Willard Farquhar (September 12, 1932 – October 18, 2015) was an American mission design specialist who worked for NASA. He designed halo orbits and was involved in a number of spaceflight missions. Robert Farquhar was born Robert Greener on September 12, 1932 in Chicago , Illinois. His father left when he was six weeks old and his mother remarried when he was thirteen years old, marr
  • 575
  • 22 Nov 2022
Topic Review
Ultrafast Laser Spectroscopy
Ultrafast laser spectroscopy is a spectroscopic technique that uses ultrashort pulse lasers for the study of dynamics on extremely short time scales (attoseconds to nanoseconds). Different methods are used to examine dynamics of charge carriers, atoms and molecules. Many different procedures have been developed spanning different time scales and photon energy ranges; some common methods are listed below.
  • 573
  • 15 Nov 2022
Topic Review
Evolution of AI and ML in Medical Infrastructure
People in the life sciences who work with Artificial Intelligence (AI) and Machine Learning (ML) are under increased pressure to develop algorithms faster than ever. The possibility of revealing innovative insights and speeding breakthroughs lies in using large datasets integrated on several levels. However, even if there is more data at our disposal than ever, only a meager portion is being filtered, interpreted, integrated, and analyzed. Both an increase in the learning capacity and the provision of a decision support system at a size that is redefining the future of healthcare are enabled by AI and ML.
  • 573
  • 31 Jan 2023
Topic Review
Blue Streak (Missile)
The de Havilland Propellers Blue Streak was a British medium-range ballistic missile (MRBM), and later the first stage of the Europa satellite launch vehicle. Blue Streak was cancelled without entering full production. The project was intended to maintain an independent British nuclear deterrent, replacing the V bomber fleet which would become obsolete by 1965. The operational requirement for the missile was issued in 1955 and the design was complete by 1957. However, during development it became clear that the missile system was too expensive and too vulnerable to a pre-emptive strike. The missile project was cancelled in 1960, with US-led Skybolt the preferred replacement. Partly to avoid political embarrassment from the cancellation, the UK Government proposed that the rocket be used as the first stage of a civilian satellite launcher called Black Prince. However, the cost was thought to be too great for the UK alone, and international collaboration was sought. This led to the formation of the European Launcher Development Organisation (ELDO), with Blue Streak used as the first stage of a carrier rocket named Europa. Europa was tested at Woomera Test Range, Australia, and later at Kourou in French Guiana. Following launch failures, the ELDO project was cancelled in 1972 and development of Blue Streak was halted.
  • 571
  • 11 Oct 2022
Topic Review
Radio Frequency Welding
Radio frequency welding, also known as dielectric welding and high frequency welding, is a plastics joining process that utilizes high-frequency radio waves to heat plastic parts to the point they form a melt layer. After the development of the melt layer, the parts are pressed together and then allowed to cool causing fusion. This process is capable of producing high quality joints in a range of plastics. Advantages of this process are fast cycle times, easily automated, repeatable, and good weld appearance. While this process has some great advantages, there are some limitations. Only plastics which have dipoles can be heated using radio waves and therefore not all plastics are able to be welded using this process. Also, this process is not well suited for thick or overly complex joints. The most common use of this process is lap joints or seals on thin plastic sheets or parts.
  • 571
  • 14 Nov 2022
Topic Review
Shingled Magnetic Recording
Shingled magnetic recording (SMR) is a magnetic storage data recording technology used in hard disk drives (HDDs) to increase storage density and overall per-drive storage capacity. Conventional hard disk drives record data by writing non-overlapping magnetic tracks parallel to each other (perpendicular magnetic recording, PMR), while shingled recording writes new tracks that overlap part of the previously written magnetic track, leaving the previous track narrower and allowing for higher track density. Thus, the tracks partially overlap similar to roof shingles. This approach was selected because, if the writing head is made too narrow, it cannot provide the very high fields required in the recording layer of the disk.:7–9 The overlapping-tracks architecture complicates the writing process since writing to one track also overwrites an adjacent track. If adjacent tracks contain valid data, they must be rewritten as well. As a result, SMR drives are divided into many append-only (sequential) zones of overlapping tracks that need to be rewritten entirely when full, resembling flash blocks in solid state drives. Device-managed SMR devices hide this complexity by managing it in the firmware, presenting an interface like any other hard disk. Other SMR devices are host-managed and depend on the operating system to know how to handle the drive, and only write sequentially to certain regions of the drive. :11 ff. While SMR drives can use DRAM and flash memory caches to improve writing performance, continuous writing of large amount of data is noticeably slower than with PMR drives.
  • 571
  • 01 Dec 2022
Topic Review
Friction-plate Electromagnetic Couplings
Electromagnetic clutches and brakes operate electrically, but transmit torque mechanically. This is why they used to be referred to as electro-mechanical clutches or brakes. Over the years, EM became known as electromagnetic versus electro mechanical, referring more about their actuation method versus physical operation. Since the clutches started becoming popular over 60 years ago, the variety of applications and brake and clutch designs has increased dramatically, but the basic operation remains the same. This article is about the working principles of single face friction plate clutches and brakes. In this article, clutches and brakes are referred to as (mechanical) couplings.
  • 570
  • 07 Oct 2022
Topic Review
Juice Jacking: Security Issues and USB Technology
For a reliable and convenient system, it is essential to build a secure system that will be protected from outer attacks and also serve the purpose of keeping the inner data safe from intruders. A juice jacking is a popular and spreading cyber-attack that allows intruders to get inside the system through the web and theive potential data from the system. For peripheral communications, Universal Serial Bus (USB) is the most commonly used standard in 5G generation computer systems. USB is not only used for communication, but also to charge gadgets. However, the transferal of data between devices using USB is prone to various security threats. It is necessary to maintain the confidentiality and sensitivity of data on the bus line to maintain integrity. 
  • 569
  • 28 Feb 2022
Topic Review
Current Sensing Techniques
In electrical engineering, current sensing is any one of several techniques used to measure electric current. The measurement of current ranges from picoamps to tens of thousands of amperes. The selection of a current sensing method depends on requirements such as magnitude, accuracy, bandwidth, robustness, cost, isolation or size. The current value may be directly displayed by an instrument, or converted to digital form for use by a monitoring or control system. Current sensing techniques include shunt resistor, current transformers and Rogowski coils, magnetic-field based transducers and others.
  • 569
  • 17 Oct 2022
Biography
Torkel Korling
Torkel Korling (April 24, 1903 – October 22, 1998) was a Swedish-born American -, commercial, portrait and botanical photographer. Torkel Korling was born into a 400-year line of Lutheran Church choir directors and organists in Kristdala, Sweden. His father, Felix Körling, was first to find success beyond the church as a composer and conductor in Sweden. Korling set out to be a botanist. T
  • 569
  • 13 Dec 2022
Topic Review
CdTe X/γ-ray Detectors
Different contact materials and optimization of techniques of their depositions expand the possibilities to obtain high performance room temperature CdTe-based X/γ-ray detectors. The heterostructures with ohmic (MoOx) and Schottky (MoOx, TiOx, TiN, and In) contacts, created by DC reactive magnetron sputtering and vacuum thermal evaporation, as well as In/CdTe/Au diodes with a p-n junction, formed by laser-induced doping, have been developed and investigated. Depending on the surface pre-treatment of semi-insulating p-CdTe crystals, the deposition of a MoOx film formed either ohmic or Schottky contacts. Based on the calculations and I-V characteristics of the Mo-MoOx/p-CdTe/MoOx-Mo, In/p-CdTe/MoOx-Mo, Ti-TiOx/p-CdTe/MoOx-Mo, and Ti-TiN/p-CdTe/MoOx-Mo Schottky-diode detectors, the current transport processes were described in the models of the carrier generation–recombination within the space-charge region (SCR) at low bias, and space-charge limited current incorporating the Poole–Frenkel effect at higher voltages, respectively. The energies of generation–recombination centers, density of trapping centers, and effective carrier lifetimes were determined. Nanosecond laser irradiation of the In electrode, pre-deposited on the p-CdTe crystals, resulted in extending the voltage range, corresponding to the carrier generation–recombination in the SCR in the I-V characteristics of the In/CdTe/Au diodes. Such In/CdTe/Au p-n junction diode detectors demonstrated high energy resolutions (7%@59.5 keV, 4%@122 keV, and 1.6%@662 keV).
  • 568
  • 08 Jun 2021
Topic Review
List of AMD Turion Microprocessors
Turion 64 is the name of a family of CPUs designed by AMD for the mobile computing market.
  • 568
  • 23 Nov 2022
Topic Review
Time Stretch Analog-to-digital Converter
The time-stretch analog-to-digital converter (TS-ADC), also known as the time stretch enhanced recorder (TiSER), is an analog-to-digital converter (ADC) system that has the capability of digitizing very high bandwidth signals that cannot be captured by conventional electronic ADCs. Alternatively, it is also known as the photonic time stretch (PTS) digitizer, since it uses an optical frontend. It relies on the process of time-stretch, which effectively slows down the analog signal in time (or compresses its bandwidth) before it can be digitized by a slow electronic ADC.
  • 566
  • 20 Oct 2022
Topic Review
DEMOnstration Power Station
DEMO (DEMOnstration Power Station) is a proposed nuclear fusion power station that is intended to build upon the ITER experimental nuclear fusion reactor. The objectives of DEMO are usually understood to lie somewhere between those of ITER and a "first of a kind" commercial station, sometimes referred to as PROTO. While there is no clear international consensus on exact parameters or scope, the following parameters are often used as a baseline for design studies: DEMO should produce at least 2 gigawatts of fusion power on a continuous basis, and it should produce 25 times as much power as required for breakeven. DEMO's design of 2 to 4 gigawatts of thermal output will be on the scale of a modern electric power station. To achieve its goals, DEMO must have linear dimensions about 15% larger than ITER, and a plasma density about 30% greater than ITER. As a prototype commercial fusion reactor, it was estimated in 2006, that DEMO could make fusion energy available by 2033, but has now been delayed. It is estimated that subsequent commercial fusion reactors could be built for about a quarter of the cost of DEMO.
  • 565
  • 10 Oct 2022
Topic Review
Load Following Power Plant
A load following power plant, regarded as producing mid-merit or mid-priced electricity, is a power plant that adjusts its power output as demand for electricity fluctuates throughout the day. Load following plants are typically in-between base load and peaking power plants in efficiency, speed of start up and shut down, construction cost, cost of electricity and capacity factor.
  • 565
  • 27 Oct 2022
Topic Review
Federation (Spacecraft)
Federation (Russian: Федерация, Federatsiya), formerly called PPTS (Prospective Piloted Transport System, Перспективная Пилотируемая Транспортная Система, Perspektivnaya Pilotiruemaya Transportnaya Sistema) is a project by Roscosmos to develop a new-generation, partially reusable piloted spacecraft. Until 2016 its official name was Пилотируемый Транспортный Корабль Нового Поколения, Pilotiruemyi Transportny Korabl Novogo Pokoleniya or PTK NP meaning "New Generation Piloted Transport Ship". The goal of the project is to develop a new-generation spacecraft to replace the aging Soyuz spacecraft developed by the former Soviet Union to support low Earth orbit and lunar operations. It is similar in function to the United States Orion spacecraft. The PPTS project was started following the failed attempt by Russia and the European Space Agency to co-develop the Crew Space Transportation System (CSTS), which until the middle of 2006 was known as the ACTS. Following this the Russian Federal Space Agency ordered the local space industry to finalize proposals for the new manned spacecraft. A firm development contract was awarded to RKK Energia on December 19, 2013. Federation will be capable of carrying crews of four into Earth orbit and beyond on missions of up to 30 days. If docked with a space station, it could stay in space up to a year, which is double the duration of the Soyuz spacecraft. The spacecraft will send cosmonauts to the moon orbit, with a plan to place a space station there.
  • 565
  • 01 Nov 2022
Biography
Patrick G. Forrester
Patrick Graham Forrester (born March 31, 1957) is a retired United States Army officer and a NASA astronaut. At the time of his retirement from the U.S. Army, Forrester had achieved the rank of colonel. He is married and has two children. Forrester has flown on three Space Shuttle missions, STS-105, STS-117 and STS-128. He is the current Chief of the Astronaut Office, having assumed the role fr
  • 564
  • 02 Dec 2022
Topic Review
Surface Laptop 3
The Surface Laptop 3 is a laptop computer developed by Microsoft. It is the third generation of Surface Laptop and was unveiled alongside the Surface Pro 7 and Surface Pro X on an event on 2 October 2019. It succeeds the Surface Laptop 2 that was released in October 2018. Surface Laptop 3 keeps the same form and design, but with an addition of a USB C port, improved battery life, an AMD CPU for the 15 inch model, a first for a surface device. Microsoft opted for an aluminum finish as an option for some models alongside the traditional Alcantara fabric covering. The device runs Windows 10 Home. The devices' display are the same as the previous models. The 13.5 inch model comes with a 2256 x 1504 resolution and the 15 inch model comes with a 2496 x 1664 resolution. Both models have the same 3:2 aspect ratio and 201 ppi. The Surface Laptop 3 13.5 inch model starts at $1,000 and goes up to $2,400. The 15 inch model starts at $1,200 and goes up to $2,800.
  • 563
  • 21 Oct 2022
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