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Topic Review
Astronomical Interferometer
An astronomical interferometer is an array of separate telescopes, mirror segments, or radio telescope antennas that work together as a single telescope to provide higher resolution images of astronomical objects such as stars, nebulas and galaxies by means of interferometry. The advantage of this technique is that it can theoretically produce images with the angular resolution of a huge telescope with an aperture equal to the separation between the component telescopes. The main drawback is that it does not collect as much light as the complete instrument's mirror. Thus it is mainly useful for fine resolution of more luminous astronomical objects, such as close binary stars. Another drawback is that the maximum angular size of a detectable emission source is limited by the minimum gap between detectors in the collector array. Interferometry is most widely used in radio astronomy, in which signals from separate radio telescopes are combined. A mathematical signal processing technique called aperture synthesis is used to combine the separate signals to create high-resolution images. In Very Long Baseline Interferometry (VLBI) radio telescopes separated by thousands of kilometers are combined to form a radio interferometer with a resolution which would be given by a hypothetical single dish with an aperture thousands of kilometers in diameter. At the shorter wavelengths used in infrared astronomy and optical astronomy it is more difficult to combine the light from separate telescopes, because the light must be kept coherent within a fraction of a wavelength over long optical paths, requiring very precise optics. Practical infrared and optical astronomical interferometers have only recently been developed, and are at the cutting edge of astronomical research. At optical wavelengths, aperture synthesis allows the atmospheric seeing resolution limit to be overcome, allowing the angular resolution to reach the diffraction limit of the optics. Astronomical interferometers can produce higher resolution astronomical images than any other type of telescope. At radio wavelengths, image resolutions of a few micro-arcseconds have been obtained, and image resolutions of a fractional milliarcsecond have been achieved at visible and infrared wavelengths. One simple layout of an astronomical interferometer is a parabolic arrangement of mirror pieces, giving a partially complete reflecting telescope but with a "sparse" or "dilute" aperture. In fact the parabolic arrangement of the mirrors is not important, as long as the optical path lengths from the astronomical object to the beam combiner (focus) are the same as would be given by the complete mirror case. Instead, most existing arrays use a planar geometry, and Labeyrie's hypertelescope will use a spherical geometry.
  • 780
  • 09 Nov 2022
Topic Review
High-Mix, Low-Volume Manufacturing Industry
The high-mix, low-volume (HMLV) industry has seen growth in the need for product customisation with research to increase manufacturers’ flexibility for the variation in market demands. Industries with HMLV insights are discussed, to reveal production sectors and research areas, categorising the research work, type of validation and their applications.
  • 780
  • 29 May 2023
Topic Review
Farming and Cultivation
We like to report on the concept of an advanced energy-engineering system for self-sustainable and rural areas farming and cultivation (RAFC). In this energy-engineering approach, we accounted for the effects of thin-film coated energy-saving features, in an optimized off-grid hybrid power generation system for advanced farm-house. Design and optimization of a hybrid (photovoltaic-battery-generator) power system have been performed by using the Hybrid Optimization of Multiple Energy Resources (HOMER Pro _ Version 3.14.0) software, developed by National Renewable Energy Limited (NREL, Boulder, CO 80301, USA). Optimized results show that the off-grid hybrid system together with the additional Low-E type coating assisted energy-saving features is more feasible for next-generation modern cultivation and farming with long-term sustainability. 
  • 779
  • 26 Oct 2020
Topic Review
Insight and Background of a Blockchain-based IoT economy
In the IoT-based economy, a large number of subjects (companies, public bodies, or private citizens) are willing to buy data or services offered by subjects that provide, operate, or host IoT devices. To support economic transactions in this setting, and to pave the way for the implementation of decentralized algorithmic governance powered by smart contracts, the adoption of the blockchain has been proposed both in scientific literature and in actual projects. The blockchain technology promises a decentralized payment system independent of (and possibly cheaper than) conventional electronic payment systems. However, there are a number of aspects that need to be considered for an effective IoT–blockchain integration. 
  • 779
  • 24 Apr 2022
Topic Review
Starch-Based Polymer Materials as Adsorbents for Water Treatment
Owing to its non-toxicity, biodegradability, and biocompatibility, starch is a naturally occurring polysaccharide that scientists are looking into as a possible environmentally friendly material for sustainable water remediation. Starch could exhibit significant adsorption capabilities towards pollutants with the substitution of amide, amino, carboxyl, and other functional groups for hydroxyl groups. Starch derivatives may effectively remove contaminants such as oil, organic solvents, pesticides, heavy metals, dyes, and pharmaceutical pollutants by employing adsorption techniques at a rate greater than 90%. The maximal adsorption capacities of starch-based adsorbents for oil and organic solvents, pesticides, heavy metal ions, dyes, and pharmaceuticals are 13,000, 66, 2000, 25,000, and 782 mg/g, respectively.
  • 779
  • 25 Jul 2023
Topic Review
Aptamer Sensors
Recently, aptamers have attracted attention in the biosensing field as signal recognition elements because of their high binding affinity toward specific targets such as proteins, cells, small molecules, and even metal ions. Aptamers have intrinsic advantages, such as their availability for both chemical modifications and conjugation with different labels, facilitating their ability to be used to construct a sensitive and highly selective platform sensor. Aptamers can be easily functionalized and engineered, providing several signaling modes such as colorimetric, fluorometric, and electrochemical, in what is known as aptasensors.
  • 779
  • 17 Jun 2021
Topic Review
Wave Energy Resource
Advanced assessment of the wave energy resource is fundamental to guarantee the implementation of energy converters in the marine environment, thus capturing the available power with maximum efficiency, reduced costs, and minimum environmental impacts. We review here the most recent resource characterizations encompassing a panel of approaches and techniques applied to available observations (in situ and satellite), hindcast and reanalysis archives, and refined numerical simulations specifically dedicated to wave power assessments. After a description of formulations adopted to characterize the wave energy flux, the review exhibits a series of energy metrics and selection indexes considered to refine the analysis. Benefits, limitations and potential of the different methods were discussed with respect to different applications in the most energetic locations around the world.
  • 778
  • 24 Apr 2021
Topic Review
Industrial Crystallization of Citrate
The citrate industry has a wide range of applications in food, pharmaceutical, and other fields. As a common class of food additives and functional supplements with tremendous development potential and strong core competitiveness, particles with good powder characteristics and functionalization are becoming one of the primary directions in the evolution of citrate into the high-end market.
  • 778
  • 11 Aug 2023
Topic Review
Agrivoltaics in Alberta Canada
As Alberta increases conventional solar power generation, land-use conflicts with agriculture increase. A solution that enables low-carbon electricity generation and continued (in some cases, increased) agricultural output is the co-locating of solar photovoltaics (PV) and agriculture: agrivoltaics.
  • 778
  • 10 Jan 2023
Topic Review
Fully Autonomous Vehicle
Fully autonomous vehicles (AV) would potentially be one of the most disruptive technologies of our time. The extent of the prospective benefits of AVs is strongly linked to how widely they will be accepted and adopted. Monitoring and tracking of individuals' reactions and intentions to use AVs are critical.
  • 777
  • 10 Dec 2020
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