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Topic Review
Non-Destructive Quality-Detection Techniques for Cereal Grains
Grain quality involves the appearance, nutritional, and safety attributes of grains. With the improvement of people’s living standards, problems pertaining to the quality of grains have received greater attention. Modern quality detection techniques feature unique advantages including rapidness, non-destructiveness, accuracy, and efficiency in detecting grain quality.
  • 915
  • 09 Jan 2023
Topic Review
Machines Additive Manufacturing
Modern-day machine applications require extraordinary performance parameters such as high power-density, integrated functionalities, improved thermal, mechanical & electromagnetic properties. Additive manufacturing (AM)offers a higher degree of design flexibility to achieve these performance parameters, which is impossible to realize through conventional manufacturing techniques.
  • 915
  • 26 Aug 2021
Topic Review
Ni-Base Superalloys
Ni-base superalloys are materials largely used in aero-space and energy production sectors, in particular for manufacturing engine parts (e.g. blades, rotors, turbine disks etc.) of aircrafts and aerospace vehicles and parts of power plants (e.g. extraction of oil and gas, nuclear reactors, etc.). At high temperature they exhibit an exceptional combination of high mechanical strength and excellent corrosion resistance. Ni-base superalloys are considered materials of strategic importance and a lot of metallurgical research has been devoted for optimizing their microstructure and improving mechanical properties so that they can operate at ever higher temperature in conditions of safety and reliability. Ni-base superalloys are strengthened by the precipitation of the ordered γ' phase, L12 Ni3(Al,Ti), crystallographically coherent to the f.c.c. γ matrix and their unique mechanical properties at high temperature result from the great microstructure stability. The volume fraction of γ' phase varies from 25% to 50% in polycrystalline superalloys and reaches about 70% in the most modern single crystal superalloys used for the first stage of aeronautical turbine blades. In order to reduce as much as possible the strain misfit between coherent γ and γ' phases (less than 0.4%) they are designed by an accurate tailoring of the chemical composition and a strict control of the process parameters; the resulting interface energy (20-30 mJ/m2) guarantees an excellent stability of the microstructure at high temperature. Other phases such as carbides, borides, γ'', η, δ, σ, µ and Laves phases may be also present with various effects on the mechanical properties; for instance, the topological closed-packed (TCP) σ, µ and Laves phases are undesirable because reduce the ductility.  In spite of the fact that Ni-base superalloys cost from 3 to 5 times the Fe-base ones, their use is expanding especially in gas turbine components for the production of energy because higher temperature of the thermal cycle guarantees greater efficiency and reduction of polluting emission. The demand of Ni-base superalloys is expected to expand also for the energy production through conventional steam turbine plants for achieving super-critical conditions with a predicted increase of efficiency to ~ 60% and reduction of CO2 to about 0.7 ton/kWatth while current sub-critical power plants have an efficiency of ~ 35% and produce 1.2 ton/kWatth of CO2. Of course, higher operating temperature involves more severe degradation of mechanical properties owing to these factors: (i) microstructure evolution including formation of undesired phases, coalescence of γ' precipitates, degeneration of carbides due to fatigue and creep exposure etc.; ii) the formation of cracks. Three topics of great industrial relevance will be discussed hereinafter: (i) microstructural stability; (ii) manufacturing parts of complex geometry; (iii) welding of superalloys. 
  • 914
  • 16 Feb 2022
Topic Review
Heat Management Strategies for an Induction Motor
Induction motors have gained a renewed interest due to this new shift from conventional power sources to electric power. These motors are known for their high commencing torque, adequate speed control, and reasonable overload capacity. However, induction motors have an innate thermal issue wherein their lifespan and performance are strongly temperature dependent. Hence, it is highly essential to focus on the thermal management aspect of these motors to ensure reliability and enhance performance. This research suggests an integrated approach with two or more cooling strategies and help to serve members of the scientific community, manufacturers or motors users who are interested in the thermal management of induction motors
  • 914
  • 15 Nov 2022
Topic Review
Computer Vision Applications in Intelligent Transportation Systems
As technology continues to develop, computer vision (CV) applications are becoming increasingly widespread in the intelligent transportation systems (ITS) context. These applications are developed to improve the efficiency of transportation systems, increase their level of intelligence, and enhance traffic safety. Advances in CV play an important role in solving problems in the fields of traffic monitoring and control, incident detection and management, road usage pricing, and road condition monitoring, among many others, by providing more effective methods.
  • 913
  • 21 Mar 2023
Topic Review
Animated Cartoon
An animated cartoon is a film for the cinema, television or computer screen, which is made using sequential drawings, as opposed to animation in general, which include films made using clay, puppets, 3D modeling and other means. Animated cartoons are still created for entertainment, commercial, educational and personal purposes.
  • 913
  • 18 Nov 2022
Topic Review
Application of CFD to Food 3D Printing
CFD (Computational Fluid Dynamics) is one of the computer simulation methods used to characterize fluid flow behavior under certain geometries with boundary conditions. The criterion for its performance is how well numerical simulation outcomes align with experimental results conducted under specific conditions, and how well simulations can predict extremely complicated processes that cannot be analyzed in the real world. CFD has gained recognition as an emerging science around the world, particularly since the late 2000s when there was a significant increase in the development and application of CFD to all areas related to fluid behaviors associated with momentum, heat, and mass transfer.
  • 913
  • 12 Nov 2021
Topic Review
WEC with Linear Generator-Based Direct Electric-Drive PTO System
The traditional wave energy converters (WECs) use hydraulic or turbine-type power take-off (PTO) mechanisms which consist of many moving parts, creating mechanical complexity and increasing the installation and maintenance costs. Linear generator-based direct-drive WECs could be a solution to overcome this problem. 
  • 913
  • 01 Sep 2022
Topic Review
New Desalination Plants
This entry analyzes the requirements for the construction of new desalination plants within a framework of sustainability: technology used, energy sources, correction of the environmental impacts generated and appropriate contractual model for their development. These attributes justify that reverse osmosis is the safest and most efficient technology among those available. It is proposed to incorporate renewable energy production sources. The need to adopt corrective measures to mitigate the impact produced on the environment and implement monitoring plans to confirm the validity of these measures will also be demonstrated. Finally, turnkey contracts are proposed because osmosis technology is complex, although the election must be justified by a decision support system.
  • 913
  • 07 Jul 2020
Topic Review
Manned Orbiting Laboratory
The Manned Orbiting Laboratory (MOL), originally referred to as the Manned Orbital Laboratory, was a never-flown part of the United States Air Force 's human spaceflight program, a successor to the canceled Boeing X-20 Dyna-Soar military reconnaissance space plane project. The project was developed from several early Air Force and NASA concepts of crewed space stations to be used for reconnaissance purposes. MOL evolved into a single-use laboratory, with which crews would be launched on 40-day missions and return to Earth using a Gemini B spacecraft, derived from NASA's Project Gemini. The MOL program was announced to the public on 10 December 1963 as an inhabited platform to prove the utility of putting people in space for military missions. Astronauts selected for the program were later told of the reconnaissance mission for the program. The contractor for the MOL was the Douglas Aircraft Company. The Gemini B was externally similar to NASA's Gemini spacecraft, although it underwent several modifications, including the addition of a circular hatch through the heat shield, which allowed passage between the spacecraft and the laboratory. MOL was canceled in 1969, during the height of the Apollo program, when it was shown that uncrewed reconnaissance satellites could achieve the same objectives much more cost-effectively. U.S. space station development was instead pursued with the civilian NASA Skylab (Apollo Applications Program) which flew in the mid-1970s. In the 1970s, the Soviet Union launched three Almaz military space stations, similar in intent to the MOL, but cancelled the program in 1977 for the same reasons. There is a MOL space suit on display at the Oklahoma City Science Museum, presumably never used.
  • 913
  • 11 Oct 2022
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