Imaging spectroscopyIn imaging spectroscopy (also hyperspectral imaging or spectral imaging) each pixel of an image acquires many bands of light intensity data from the spectrum, instead of just the three bands of the RGB color model. More precisely, it is the simultaneous acquisition of spatially in many spectrally contiguous bands. Some spectral images contain only a few s of a spectral data cube, while others are better thought of as full spectra at every location in the image.
Knowledge by acquaintanceIn philosophy, a distinction is often made between two different kinds of knowledge: knowledge by acquaintance and knowledge by description. Whereas knowledge by description is something like ordinary propositional knowledge (e.g. "I know that snow is white"), knowledge by acquaintance is familiarity with a person, place, or thing, typically obtained through perceptual experience (e.g. "I know Sam", "I know the city of Bogotá", or "I know Russell's Problems of Philosophy").
Optical sortingOptical sorting (sometimes called digital sorting) is the automated process of sorting solid products using cameras and/or lasers. Depending on the types of sensors used and the software-driven intelligence of the system, optical sorters can recognize an object's color, size, shape, structural properties and chemical composition. The sorter compares objects to user-defined accept/reject criteria to identify and remove defective products and foreign material (FM) from the production line, or to separate product of different grades or types of materials.
Earth observationEarth observation (EO) is the gathering of information about the physical, chemical, and biological systems of the planet Earth. It can be performed via remote-sensing technologies (Earth observation satellites) or through direct-contact sensors in ground-based or airborne platforms (such as weather stations and weather balloons, for example). According to the Group on Earth Observations (GEO), the concept encompasses both "space-based or remotely-sensed data, as well as ground-based or in situ data".
Radar astronomyRadar astronomy is a technique of observing nearby astronomical objects by reflecting radio waves or microwaves off target objects and analyzing their reflections. Radar astronomy differs from radio astronomy in that the latter is a passive observation (i.e., receiving only) and the former an active one (transmitting and receiving). Radar systems have been conducted for six decades applied to a wide range of Solar System studies. The radar transmission may either be pulsed or continuous.
Würzburg radarThe low-UHF band Würzburg radar was the primary ground-based tracking radar for the Wehrmacht's Luftwaffe and Kriegsmarine (German Navy) during World War II. Initial development took place before the war and the apparatus entered service in 1940. Eventually, over 4,000 Würzburgs of various models were produced. It took its name from the city of Würzburg. There were two primary models of the system. The first Würzburg was a transportable model that could be folded for transit and then brought into operation quickly after emplacement and levelling.
Ground-penetrating radarGround-penetrating radar (GPR) is a geophysical method that uses radar pulses to image the subsurface. It is a non-intrusive method of surveying the sub-surface to investigate underground utilities such as concrete, asphalt, metals, pipes, cables or masonry. This nondestructive method uses electromagnetic radiation in the microwave band (UHF/VHF frequencies) of the radio spectrum, and detects the reflected signals from subsurface structures. GPR can have applications in a variety of media, including rock, soil, ice, fresh water, pavements and structures.
Physical Review LettersPhysical Review Letters (PRL), established in 1958, is a peer-reviewed, scientific journal that is published 52 times per year by the American Physical Society. As also confirmed by various measurement standards, which include the Journal Citation Reports impact factor and the journal h-index proposed by Google Scholar, many physicists and other scientists consider Physical Review Letters to be one of the most prestigious journals in the field of physics. PRL is published as a print journal, and is in electronic format, online and CD-ROM.
Stealth aircraftStealth aircraft are designed to avoid detection using a variety of technologies that reduce reflection/emission of radar, infrared, visible light, radio frequency (RF) spectrum, and audio, collectively known as stealth technology. The F-117 Nighthawk was the first operational aircraft specifically designed around stealth technology. Other examples of stealth aircraft include the B-2 Spirit, the B-21 Raider, the F-22 Raptor, the F-35 Lightning II, the Chengdu J-20, and the Sukhoi Su-57.
PotatoThe potato is a starchy food, a tuber of the plant Solanum tuberosum and is a root vegetable native to the Americas. The plant is a perennial in the nightshade family Solanaceae. Wild potato species can be found from the southern United States to southern Chile. The potato was originally believed to have been domesticated () by Native Americans independently in multiple locations, but later genetic studies traced a single origin, in the area of present-day southern Peru and extreme northwestern Bolivia.
