Average absolute deviationThe average absolute deviation (AAD) of a data set is the average of the absolute deviations from a central point. It is a summary statistic of statistical dispersion or variability. In the general form, the central point can be a mean, median, mode, or the result of any other measure of central tendency or any reference value related to the given data set. AAD includes the mean absolute deviation and the median absolute deviation (both abbreviated as MAD). Several measures of statistical dispersion are defined in terms of the absolute deviation.
Phase-contrast X-ray imagingPhase-contrast X-ray imaging or phase-sensitive X-ray imaging is a general term for different technical methods that use information concerning changes in the phase of an X-ray beam that passes through an object in order to create its images. Standard X-ray imaging techniques like radiography or computed tomography (CT) rely on a decrease of the X-ray beam's intensity (attenuation) when traversing the sample, which can be measured directly with the assistance of an X-ray detector.
History of fashion designHistory of fashion design refers specifically to the development of the purpose and intention behind garments, shoes ,accessories, and their design and construction. The modern industry, based around firms or fashion houses run by individual designers, started in the 19th century with Charles Frederick Worth who, beginning in 1858, was the first designer to have his label sewn into the garments he created. Fashion started when humans began wearing clothes. These clothes were typically made from plants, animal skins and bone.
Standard deviationIn statistics, the standard deviation is a measure of the amount of variation or dispersion of a set of values. A low standard deviation indicates that the values tend to be close to the mean (also called the expected value) of the set, while a high standard deviation indicates that the values are spread out over a wider range. Standard deviation may be abbreviated SD, and is most commonly represented in mathematical texts and equations by the lower case Greek letter σ (sigma), for the population standard deviation, or the Latin letter s, for the sample standard deviation.
French fashionFashion in France is an important subject in the culture and country's social life, as well, being an important part of its economy. Fashion design and production became prominent in France since 15th century. During the 17th century, fashion exploded into a rich industry, for exportation and local consumption. In the 19th century, fashion made a transition into specialisation for modern term haute couture, originated in the 1860s, bringing good taste to fashion argot.
Italian fashionItaly is one of the leading countries in fashion design, alongside France, the United States and the United Kingdom. Fashion has always been an important part of the country's cultural life and society, and Italians are well known for their attention to dress; la bella figura, or good appearance, retains its traditional importance. Italian fashion became prominent during the 11th to 16th centuries, when artistic development in Italy was at its peak.
Covariance matrixIn probability theory and statistics, a covariance matrix (also known as auto-covariance matrix, dispersion matrix, variance matrix, or variance–covariance matrix) is a square matrix giving the covariance between each pair of elements of a given random vector. Any covariance matrix is symmetric and positive semi-definite and its main diagonal contains variances (i.e., the covariance of each element with itself). Intuitively, the covariance matrix generalizes the notion of variance to multiple dimensions.
Sine and cosine transformsIn mathematics, the Fourier sine and cosine transforms are forms of the Fourier transform that do not use complex numbers or require negative frequency. They are the forms originally used by Joseph Fourier and are still preferred in some applications, such as signal processing or statistics. The Fourier sine transform of f(t), sometimes denoted by either or , is If t means time, then ξ is frequency in cycles per unit time, but in the abstract, they can be any pair of variables which are dual to each other.
FashionFashion is a term used interchangeably to describe the creation of clothing, footwear, accessories, cosmetics, and jewellery of different cultural aesthetics and their mix and match into outfits that depict distinctive ways of dressing (styles and trends) as signifiers of social status, self-expression, and group belonging. As a multifaceted term, fashion describes an industry, styles, aesthetics, and trends.
Fractional Fourier transformIn mathematics, in the area of harmonic analysis, the fractional Fourier transform (FRFT) is a family of linear transformations generalizing the Fourier transform. It can be thought of as the Fourier transform to the n-th power, where n need not be an integer — thus, it can transform a function to any intermediate domain between time and frequency. Its applications range from filter design and signal analysis to phase retrieval and pattern recognition.
