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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.
A form of water in which the hydrogen atoms of mass 1 (<sup>1</sup>H) ordinarily present in water are replaced by deuterium (symbol D or <sup>2</sup>H), the heavy stable isotope of hydrogen of mass 2. The molecular formula of heavy water is D<sub>2</sub>O (or <sup>2</sup>H<sub>2</sub>O).
Industry:Science
A formal computerized approach to inventory planning, manufacturing scheduling, supplier scheduling, and overall corporate planning. The material requirements planning (MRP) system provides the user with information about timing (when to order) and quantity (how much to order), generates new orders, and reschedules existing orders as necessary to meet the changing requirements of customers and manufacturing. The system is driven by change and constantly recalculates material requirements based on actual forecast orders. It makes adjustments for possible problems prior to their occurrence, as opposed to traditional control systems, which looked at more historical demand and reacted to existing problems. Material resource planning (MRP II) evolved from material requirements planning when it was recognized that most major data needed to manage a manufacturing or distribution firm could be obtained from the material requirements planning information. The ability of a material resource planning system to meet the various needs of manufacturing, materials, and marketing personnel within a changing business environment contributes to its growing implementation by manufacturing companies.
Industry:Science
A former widely recognized subclass of Magnoliophyta (angiosperms or flowering plants). Deoxyribonucleic acid (DNA) and morphological studies have demonstrated that this group includes many more families than previously thought (for example, a large number of families previously referred to the subclass Dilleniidae). Whereas formal reclassification awaits further evidence, it is clear that there is a large group that can be considered rosid. Approximately 136 families (roughly 30% of the total angiosperms) in 11 orders are included in the rosids. With the asterids (often recognized as Asteridae), the rosids represent the two most advanced lines of dicots.
Industry:Science
A formulation of quantum theory in which the operators are represented by time-dependent matrices. For a discussion of quantum-mechanical operators and other information essential to an understanding of this article
Industry:Science
A fossil lobe-finned (sarcopterygian) fish from rock strata of the Baltic region dating to the Middle–Late Devonian Period (about 372–368 million years ago), which provides key evidence about the evolutionary transition from fish to land vertebrates (tetrapods). As the most tetrapod-like fish known, it reveals the earliest steps of the transformation that adapted the fish body plan to terrestrial life.
Industry:Science
A fossilization, or taphonomic, process characterized by the deposition of a mineral or mineraloid (an amorphous “gel mineral”) in the pore spaces of an organism's body structures. Pores in bone, shell, or plant material may be impregnated by minerals or mineraloids precipitated from ground water, lake or stream water, or ocean water. Minerals commonly involved in permineralization are quartz, calcite, pyrite, siderite (iron carbonate), and apatite (calcium phosphate). Opal, a mineraloid, is also a common agent of permineralization. Normally, the structural parts of organisms undergo little, if any, shape change as the pores are filled, leading in many examples to exquisite preservation of the fine structural details of bodily remains.
Industry:Science
A foundational quantity in physics that is always conserved in isolated systems, defined in classical mechanics as the product of mass and velocity. An equivalent definition that is better suited to modern physics is that momentum is the rate of change of energy with respect to velocity: this allows extending the conservation laws to include entities of zero mass. Whenever energy is transported from one system to another, it is always associated with some form of momentum.
Industry:Science
A four-bar parallel linkage, with no links fixed, used as a copying device for generating geometrically similar figures, larger or smaller in size, within the limits of the mechanism. In the <b>illustration</b> the curve traced by point <i>T</i> will be similar to that generated by point <i>S</i>. This similarity results because points <i>T</i> and <i>S</i> will always lie on the straight line <span style="text-decoration:overline"><i>OTS</i></span>; triangles <i>OBS</i> and <i>TCS</i> are always similar because lengths <span style="text-decoration:overline"><i>OB</i></span>, <span style="text-decoration:overline"><i>BS</i></span>, <span style="text-decoration:overline"><i>CT</i></span>, and <span style="text-decoration:overline"><i>CS</i></span> are constant and <span style="text-decoration:overline"><i>OB</i></span> is always parallel to <span style="text-decoration:overline"><i>CT</i></span>. Distance <span style="text-decoration:overline"><i>OT</i></span> always maintains a constant proportion to distance <span style="text-decoration:overline"><i>OS</i></span> because of the similarity of the above triangles. Numerous modifications of the pantograph as a copying device have been made.
Industry:Science
A framework for solving a problem. The analytic hierarchy process is a systematic procedure for representing the elements of any problem. It organizes the basic rationality by breaking down a problem into its smaller constituents and then calls for only simple pairwise comparison judgments, to develop priorities in each level.
Industry:Science
A framework structure silicate of the feldspathoidal mineral group. It is commonly found as euhedral phenocrysts in K<sub>2</sub>O-rich and SiO<sub>2</sub>-poor volcanic rocks, consistent with its chemical composition, (K,Na)AlSi<sub>2</sub>O<sub>6</sub>, where K is more abundant than Na. The crystals are typically white, and the luster varies from dull to vitreous. Mohs hardness lies between 5.5 and 6. Density ranges from 2.45 to 2.5. Crystals, exhibiting the characteristic isometric trapezohedral form (see <b>illus.</b>), as large as 7 cm (3 in.) are common in the lavas of Nyiragongo volcano, Zaire. Other well-known areas include West Kimberley, Australia; Mount Vesuvius, Italy; Highwood Mountains and Bearpaw Mountains, Montana; and the Leucite Hills, Wyoming.
Industry:Science
