- 行业: Printing & publishing
- Number of terms: 178089
- Number of blossaries: 0
- Company Profile:
McGraw Hill Financial, Inc. is an American publicly traded corporation headquartered in Rockefeller Center in New York City. Its primary areas of business are financial, publishing, and business services.
Inkjet printing refers to a family of related technologies in which airborne droplets of ink are electronically guided to form images. The roots of this technology reach as far back as 1867, when William Thomson (later, Lord Kelvin) acquired a patent for “Receiving or Recording Instruments for Electrical Telegraphers.” The system used electrostatic forces to control the release of ink drops onto paper to record telegraph messages. In 1951, Siemens patented the first continuous-stream inkjet printer, but it achieved little commercial success. Later patents by Winston, Ascoli, Sweet, Hertz, Elmquist, and others led to commercially successful printers from A. B. Dick, Mead, and Toshiba in the 1960s.
Industry:Science
Lists or enumerations of astronomical data relevant to astronomy, navigation, geodesy, and space science applications. Astronomical catalogs vary a great deal in form and content depending upon the type of the data and the objects to which they are referring. The essential data may be positions and motions of the celestial objects, magnitudes, spectra, radial velocities of stars, or energy fluxes. The celestial objects may be stars, galaxies and other galactic and extragalactic objects, or solar system bodies, which are generally ordered by increasing right ascensions and identified by a catalog number. Catalogs are either derived directly from observations or are compiled from different sources.
Industry:Science
Nonnative organisms that cause a major change to native ecosystems—once called foreign species, biological invasions, alien invasives, exotics, or biohazards—are now generally referred to as invasive species or invasives. Invasive species of insects, fungi, plants, fish, and other organisms present a rising threat to natural forest ecosystems worldwide. Invasive animals are transferred to ecosystems in which there are no natural predators to keep them from spreading. Many species escape into the new environment where they become established, upsetting the ecological balance of the native forest ecosystem. Some invasives are competitors or predators of native species, whereas others cause disease.
Industry:Science
Microphones have advanced tremendously since Thomas Edison patented a device in 1877 based on the resistance of carbon granules. The most commonly used microphone today is the foil electret microphone, which was developed in the 1960s, and enabled microphones to be easily incorporated into a multitude of products. It appears that a new breakthrough in microphone technology may be imminent: the MEMS microphone. MEMS, an acronym for microelectromechanical systems, refers to any small mechanical device that can be fabricated on a silicon chip, often connected to some form of electrical system. A MEMS microphone can be very small (less than 1 mm) and can be incorporated directly onto an electronic chip.
Industry:Science
One of the bent grasses, <i>Agrostis alba</i> and its relatives, which occur in cooler, more humid regions of the United States on a wide variety of soils. Redtop tolerates both wet and dry lands and acid and infertile soils, and it is used where other species of grasses do not thrive. Redtop is a perennial, spreads slowly by rootstocks, and makes a coarse, loose turf. Top growth is 2–3 ft (0.6–0.9 m) tall, with moderately leafy, wiry stems. The inflorescence is a reddish open panicle. Redtop is used for pasture and hay and is fairly nutritious if harvested promptly when heading occurs. It is effective in preventing erosion by holding banks of drainage ditches, waterways, and terrace channels.
Industry:Science
In recent years, many natural and human-induced disasters have demonstrated to the public the interconnectedness and interdependence of critical infrastructures. The ease with which these connections and dependencies occur within systems is known as interoperability. From the Haiti and Chile earthquakes, to the volcanic ashes in Scandinavia, to the BP (British Petroleum) rig explosion and the oil spill in the Gulf of Mexico, to the financial crisis in Greece and southern Europe, the consequences and ripple effects of these interdependencies create many unintended consequences. Although disasters are never completely predictable, new tools are available to help to prepare and respond more effectively.
Industry:Science
One of the biggest challenges of deep space exploration is communicating over links spanning distances of solar system scale. Compared to a typical commercial link between a geostationary satellite and a user on the Earth's surface, which spans a distance of roughly 40,000 km (25,000 mi), a link between Mars and Earth can be up to 4 × 10<sup>8</sup> km (2.5 × 10<sup>8</sup> mi), and links to a Jupiter spacecraft can approach 10<sup>9</sup> km (6 × 10<sup>8</sup> mi). Because the performance of a communications system scales inversely as the square of link distance, these deep-space links pose unique problems and, in many cases, fundamentally limit the quantity of scientific data that can be returned.
Industry:Science
Power-line telecommunications (PLT) means the use of existing electric power lines (mains wiring) for broadband communications purposes. To achieve data rates of the order of tens of megabits per second, a frequency range up to tens of megahertz (typically, 30 MHz) is used. Electric power cables (mains cables) were not originally designed to carry broadband communication signals and actually have a configuration and layout that cause them to act as antennas at high-frequency (HF; 2–30 MHz) radio frequencies. Therefore, there is potential for interference to HF radio systems near a PLT installation, as well as at large distances due to cumulative contributions from a large number of PLT installations.
Industry:Science
Late in the nineteenth century, the Dutch physician Eugene Dubois traveled as a military doctor to the Dutch East Indies (now Indonesia) in search of the fossil remains of human ancestors. He was following the predictions of Ernst Haeckel, who anticipated a prehuman ancestor that walked upright but did not speak (“Pithecanthropus alalus”), and surmised that the tropics would be the origin of modern humans. His search was rewarded in the 1890s when workers discovered the skull cap of an early human at the site of Trinil along the Solo River of Java. From the same locality, but perhaps younger in age, came upper leg bones as well. Dubois named the fossils <i>Pithecanthropus erectus</i>, upright ape-man.
Industry:Science
Initially inapparent (covert) viral infections in which an equilibrium between the virus and the host has been established. Pathology may occur periodically, or chronically at a low level. If manifested in degenerative diseases of the central nervous system, these infections may result in death. The basis of these infections is an uncharacteristically low level of viral replication which may persist throughout the normal lifetime of the host, and which may follow the recovery from a more severe bout with the virus. The acute illness may have elicited production of antibodies, and an equilibrium between virus neutralization and antibody generation is established which may produce life-long immunity.
Industry:Science
