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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 branch of meteorology and ecology that deals with the effects of weather and climate on plants, animals, and humans.
Industry:Science
A branch of meteorology that examines the effects and impacts of weather and climate on crops, rangeland, livestock, and various agricultural operations. The branch of agricultural meteorology dealing with atmospheric-biospheric processes occurring at small spatial scales and over relatively short time periods is known as micrometeorology, sometimes called crop micrometeorology for managed vegetative ecosystems and animal biometeorology for livestock operations. The branch that studies the processes and impacts of climatic factors over larger time and spatial scales is often referred to as agricultural climatology.
Industry:Science
A branch of modern control theory that deals with designing controls for linear systems by minimizing a performance index that depends on the system variables. Under some mild assumptions, making the performance index small also guarantees that the system variables will be small, thus ensuring closed-loop stability.
Industry:Science
A branch of paleontology dealing with the fossilized microscopic organic remains (microfossils) of the geologic past, their structure, biology, phylogenetic relations, and distribution in space and time. The study of these microfossils has become an independent scientific field largely because of the following: (1) The size of these fossils requires special methods for collection and examination. (2) Their abundance in geologic formations makes it possible to analyze their spatial distribution and the rates of morphological changes during the course of evolution by means of statistical methods which can be used only under exceptional circumstances in the study of larger fossils. (3) Microfossils have become indispensable tools in certain branches of applied geology, especially in the exploration for oil-bearing strata, because countless numbers of these minute fossils may be obtained from small pieces of subsurface rock recovered from drill holes. (4) The diversity of microfossils, their wide spatial distribution in varied environments, and their distinctive steps in evolution and the ease of studying them have contributed to make micropaleontology one of the most actively studied branches of the earth sciences. Many organisms are restricted to certain environments best suited to their life activities. The occurrence of certain organisms in sediments, therefore, can in turn provide a clue to a particular environment that existed in the past. Micropaleontologists can obtain important information about depositional environments, such as their ancient environment, water depth, temperature, current systems, water mass distribution, proximity of shore lines and, of course, these organisms are used to date ages of enclosing sediments.
Industry:Science
A branch of physical chemistry concerned with the absorption or evolution of heat that accompanies chemical reactions. Closely related topics are the latent heat associated with a change in phase (crystal, liquid, gas), the chemical composition of reacting systems at equilibrium, and the electrical potentials of galvanic cells. Thermodynamics provides the link among these phenomena.
Industry:Science
A branch of physical chemistry that seeks to measure the rates of chemical reactions, describe them in terms of elementary steps, and understand them in terms of the fundamental interactions between molecules.
Industry:Science
A branch of physics dealing with physical properties of matter at temperatures such that thermal fluctuations are greatly reduced and effects of interactions at the quantum-mechanical level can be observed. As the temperature is lowered, order sets in (either in space or in motion), and quantum-mechanical phenomena can be observed on a macroscopic scale. As an example, consider a magnetic system. In a sample at high temperatures, there is a high degree of disorder corresponding to a large entropy because of the random orientations of its magnetic moments, the sample being in a paramagnetic state. At low temperatures, the sample is in a highly ordered state, the ferromagnetic state (lower entropy), and the details of the interactions responsible for this state can be studied.
Industry:Science
A branch of probability and statistics concerned with deriving information about properties of random variables, stochastic processes, and systems based on observed samples. Some of the important applications of estimation theory are found in control and communication systems, where it is used to estimate the unknown states and parameters of the system. For example, the position and velocity of a satellite is estimated from ground radar observations of its range, elevation, and azimuth. These observations are contaminated with random noise due to atmospheric propagation and radar circuitry. The statistical properties of random noise are assumed known except for some parameters which can be estimated from the data. Generally, the random noise is assumed to have a gaussian distribution, and its mean and covariance may be known or unknown. It is also assumed to be “white,” that is, uncorrelated from one time instant to the next. The integral of white noise is a Wiener process or brownian motion process which plays a fundamental role in the theory of stochastic processes.
Industry:Science
A branch of psychology concerned with developing a scientifically defensible conception of human nature—in modern parlance, a general theory of behavior. Personality theory is an outgrowth of nineteenth-century French and German psychiatry. Nineteenth-century psychiatry was a practical rather than an academic discipline, concerned with the origins and treatment of psychopathology. It dealt with abnormal rather than normal thought processes and focused on the unconscious rather than the conscious mind. Perhaps most distinctively, it considered a single person as the unit of study, in contrast to academic psychology's focus on a single perception or behavioral response. These themes continue today. Thus, with only a few exceptions, the prominent personality theorists have been psychiatrists or clinical psychologists, and personality psychology has developed largely outside the mainstream of academic psychology. The major exceptions are those personality theorists who have a behaviorist orientation, who stress the role of learning in personality development: John Dollard, Neal Miller, Albert Bandura, and Walter Mischel.
Industry:Science
A branch of science concerned with the scope and limitations of the various rules, effects, and generalizations in use in organic chemistry by means of physical and mathematical methods. It includes, but is not limited to, the dynamics and energetics of organic chemical transformations, transient intermediates in these reactions, rate comparisons between families of reactions, dynamic stereochemistry, conservation of orbital symmetry, the least-motion principle, the isomer number for a given elemental composition, conformational analysis, nonexistent compounds, aromaticity, tautomerism, strain and steric hindrance, and the double-bond rule. Spectroscopy is the main tool employed, with nuclear magnetic resonance being the most widely used spectroscopic technique. With the advent of modern fast computers, computational chemistry has also become an important tool.
Industry:Science
