17-letter words containing m, e, a, t, n
- fractal dimension — (mathematics) A common type of fractal dimension is the Hausdorff-Besicovich Dimension, but there are several different ways of computing fractal dimension. Fractal dimension can be calculated by taking the limit of the quotient of the log change in object size and the log change in measurement scale, as the measurement scale approaches zero. The differences come in what is exactly meant by "object size" and what is meant by "measurement scale" and how to get an average number out of many different parts of a geometrical object. Fractal dimensions quantify the static *geometry* of an object. For example, consider a straight line. Now blow up the line by a factor of two. The line is now twice as long as before. Log 2 / Log 2 = 1, corresponding to dimension 1. Consider a square. Now blow up the square by a factor of two. The square is now 4 times as large as before (i.e. 4 original squares can be placed on the original square). Log 4 / log 2 = 2, corresponding to dimension 2 for the square. Consider a snowflake curve formed by repeatedly replacing ___ with _/\_, where each of the 4 new lines is 1/3 the length of the old line. Blowing up the snowflake curve by a factor of 3 results in a snowflake curve 4 times as large (one of the old snowflake curves can be placed on each of the 4 segments _/\_). Log 4 / log 3 = 1.261... Since the dimension 1.261 is larger than the dimension 1 of the lines making up the curve, the snowflake curve is a fractal. [sci.fractals FAQ].
- front-end payment — a payment required or incurred in advance of a project in order to get it under way
- functional isomer — any of several structural isomers that have the same molecular formula but with the atoms connected in different ways and therefore falling into different functional groups.
- garden apartments — a complex of low apartment buildings surrounded by lawn or landscaped areas
- garden mignonette — a Mediterranean plant, Resida odorata, which has spikes of small greenish-white flowers with prominent anthers
- gastroenterostomy — the making of a new passage between the stomach and the duodenum (gastroduodenostomy) or, especially, the jejunum (gastrojejunostomy)
- gastrojejunostomy — See under gastroenterostomy.
- general sarmiento — a city in E Argentina, a suburb of Buenos Aires.
- general semantics — a philosophical approach to language, developed by Alfred Korzybski, exploring the relationship between the form of language and its use and attempting to improve the capacity to express ideas.
- genetic algorithm — (GA) An evolutionary algorithm which generates each individual from some encoded form known as a "chromosome" or "genome". Chromosomes are combined or mutated to breed new individuals. "Crossover", the kind of recombination of chromosomes found in sexual reproduction in nature, is often also used in GAs. Here, an offspring's chromosome is created by joining segments choosen alternately from each of two parents' chromosomes which are of fixed length. GAs are useful for multidimensional optimisation problems in which the chromosome can encode the values for the different variables being optimised.
- gentleman-at-arms — (in England) one of a guard of 40 gentlemen who attend the sovereign on state occasions.
- geomagnetic storm — magnetic storm.
- geothermal energy — Geothermal energy is energy from temperature differences inside the earth's crust.
- gethsemane cheese — a semisoft, mild, yellow cheese from whole milk, made by Trappist monks.
- glove compartment — a compartment in the dashboard of an automobile for storing small items.
- go on the rampage — If people go on the rampage, they rush about in a wild or violent way, causing damage or destruction.
- government action — intervention by a government, esp to influence financial markets
- grand climacteric — Physiology. a period of decrease of reproductive capacity in men and women, culminating, in women, in the menopause.
- grandmother clock — a pendulum clock similar to a grandfather's clock but shorter.
- great namaqualand — an arid coastal region in the S part of Namibia, extending into the Cape of Good Hope province of the Republic of South Africa, divided by the Orange River into two regions, one in Namibia (Great Namaqualand) the other in South Africa (Little Namaqualand) inhabited by the Nama.
- great-grandmother — a grandmother of one's father or mother.
- guardian ad litem — a person appointed by a court as guardian of an infant or other person to act on his or her behalf in a particular action or proceeding.
- haemagglutinating — That agglutinates red blood cells.
- haemagglutination — Alternative form of hemagglutination.
- haematocrystallin — Alternative form of hematocrystallin.
- haemoglobinometer — an instrument used to determine the haemoglobin content of blood
- haemoglobinopathy — (medicine) Any of a group of inherited disorders in which haemoglobin does not function properly.
- hamiltonian cycle — Hamiltonian problem
- hanging committee — a group of people that selects and hangs works of art to exhibit
- harmonic interval — an intervening period of time: an interval of 50 years.
- heat of formation — the heat evolved or absorbed when one mole of a compound is formed from its constituent atoms
- hemoconcentration — an increase in the concentration of cellular elements in the blood, resulting from loss of plasma.
- heteronormativity — The view that all human beings are either male or female, both in sex and in gender, and that sexual and romantic thoughts and relations are normal only when between people of different sexes.
- histamine blocker — any of various substances that act at a specific receptor site to block certain actions of histamine.
- hollerith, herman — Herman Hollerith
- homeland security — national defence
- homogentisic acid — an intermediate compound in the metabolism of tyrosine and of phenylalanine, found in excess in the blood and urine of persons affected with alkaptonuria.
- honorable mention — a citation conferred on a contestant, exhibit, etc., having exceptional merit though not winning a top honor or prize.
- hormone treatment — any of several medical treatments using hormones
- hydrothermal vent — an opening on the floor of the sea from which hot, mineral-rich solutions issue. Compare vent1 (def 2).
- hydroxytryptamine — (organic compound) Any hydroxy derivative of tryptamine, but especially 5-hydroxytryptamine (serotonin).
- hyperalimentation — overfeeding.
- hyperpigmentation — coloration, especially of the skin.
- iambic pentameter — a verse line consisting of five metrical iambs
- illegal immigrant — a person who has entered a country illegally
- image enhancement — a method of improving the definition of a video picture by a computer program, which reduces the lowest grey values to black and the highest to white: used for pictures from microscopes, surveillance cameras, and scanners
- image intensifier — any of various devices for amplifying the intensity of an optical image, sometimes used in conjunction with an image converter
- image recognition — (graphics, artificial intelligence) The identification of objects in an image. This process would probably start with image processing techniques such as noise removal, followed by (low-level) feature extraction to locate lines, regions and possibly areas with certain textures. The clever bit is to interpret collections of these shapes as single objects, e.g. cars on a road, boxes on a conveyor belt or cancerous cells on a microscope slide. One reason this is an AI problem is that an object can appear very different when viewed from different angles or under different lighting. Another problem is deciding what features belong to what object and which are background or shadows etc. The human visual system performs these tasks mostly unconsciously but a computer requires skillful programming and lots of processing power to approach human performance.
- imitation doublet — a doublet formed entirely of glass.
- immediate annuity — an annuity bought with a single premium, with payments to the annuitant to begin at the end of one payment period, as a month or a year.