Pattern recognition systems are in many cases trained from labeled training data, but when no labeled data are available other algorithms can be used to discover previously unknown patterns. The terms pattern recognition, machine learning, data mining and knowledge discovery in databases are hard to separate, in pattern recognition, there may be a higher interest to formalize and visualize the pattern, while machine learning traditionally focuses on maximizing the recognition rates. In machine learning, pattern recognition is the assignment of a label to an input value. In statistics, discriminant analysis was introduced for this purpose in 1936. An example of pattern recognition is classification, which attempts to assign each input value to one of a set of classes. However, pattern recognition is a general problem that encompasses other types of output as well. Pattern recognition algorithms generally aim to provide an answer for all possible inputs and to perform most likely matching of the inputs.
This is opposed to pattern matching algorithms, which look for matches in the input with pre-existing patterns. Pattern recognition is generally categorized according to the type of learning procedure used to generate the output value, supervised learning assumes that a set of training data has been provided, consisting of a set of instances that have been properly labeled by hand with the correct output. A combination of the two that has recently been explored is semi-supervised learning, which uses a combination of labeled and unlabeled data. Note that in cases of unsupervised learning, there may be no training data at all to speak of, in other words, Note that sometimes different terms are used to describe the corresponding supervised and unsupervised learning procedures for the same type of output. Note that in some fields, the terminology is different, For example, in community ecology, the piece of input data for which an output value is generated is formally termed an instance. The instance is formally described by a vector of features, which constitute a description of all known characteristics of the instance.
Typically, features are either categorical, integer-valued or real-valued, often and ordinal data are grouped together, likewise for integer-valued and real-valued data. Furthermore, many algorithms work only in terms of categorical data, many common pattern recognition algorithms are probabilistic in nature, in that they use statistical inference to find the best label for a given instance. Unlike other algorithms, which output a best label, often probabilistic algorithms output a probability of the instance being described by the given label. In addition, many probabilistic algorithms output a list of the N-best labels with associated probabilities, for some value of N, when the number of possible labels is fairly small, N may be set so that the probability of all possible labels is output. Probabilistic algorithms have many advantages over non-probabilistic algorithms, They output a confidence value associated with their choice, they can abstain when the confidence of choosing any particular output is too low
Dynamic light scattering
Dynamic light scattering is a technique in physics that can be used to determine the size distribution profile of small particles in suspension or polymers in solution. In the scope of DLS, temporal fluctuations are analyzed by means of the intensity or photon auto-correlation function. It has been shown that the intensity ACF is the Fourier transformation of the power spectrum, DLS can be used to probe the behavior of complex fluids such as concentrated polymer solutions. A monochromatic light source, usually a laser, is shot through a polarizer, the scattered light goes through a second polarizer where it is collected by a photomultiplier and the resulting image is projected onto a screen. This is known as a speckle pattern, all of the molecules in the solution are being hit with the light and all of the molecules diffract the light in all directions. The diffracted light from all of the molecules can either interfere constructively or destructively and this process is repeated at short time intervals and the resulting set of speckle patterns are analyzed by an autocorrelator that compares the intensity of light at each spot over time.
The polarizers can be set up in two geometrical configurations, One is a vertical/vertical geometry, where the second polarizer allows light through that is in the same direction as the primary polarizer. In vertical/horizontal geometry the second polarizer allows light not in direction as the incident light. When light hits small particles, the light scatters in all directions as long as the particles are small compared to the wavelength, even if the light source is a laser, and thus is monochromatic and coherent, the scattering intensity fluctuates over time. This fluctuation is due to molecules in solutions are undergoing Brownian motion. Sample preparation either by filtration or centrifugation is critical to remove dust, the dynamic information of the particles is derived from an autocorrelation of the intensity trace recorded during the experiment. The angular brackets <> denote the expected value operator, which in some texts is denoted by a capital E. At short time delays, the correlation is high because the particles do not have a chance to move to an extent from the initial state that they were in.
The two signals are thus essentially unchanged when compared after only a short time interval. This exponential decay is related to the motion of the particles, to fit the decay, numerical methods are used, based on calculations of assumed distributions. If the sample is the decay is simply a single exponential. It is roughly equal to the inverse of the number of speckle from which light is collected, a smaller focus of the laser beam yields a coarser speckle pattern, a lower number of speckle on the detector, and thus a larger second order autocorrelation. The most important use of the function is its use for size determination
A logarithmic scale is a nonlinear scale used when there is a large range of quantities. Common uses include the strength, sound loudness, light intensity. It is based on orders of magnitude, rather than a linear scale. In particular our sense of hearing perceives equal ratios of frequencies as equal differences in pitch, the top left graph is linear in the X and Y axis, and the Y-axis ranges from 0 to 10. A base-10 log scale is used for the Y axis of the left graph. The top right graph uses a scale for just the X axis. A slide rule has logarithmic scales, and nomograms often employ logarithmic scales, the geometric mean of two numbers is midway between the numbers. Before the advent of graphics, logarithmic graph paper was a commonly used scientific tool. If both the vertical and horizontal axes of a plot are scaled logarithmically, the plot is referred to as a log–log plot, if only the ordinate or abscissa is scaled logarithmically, the plot is referred to as a semi-logarithmic plot. Bit Byte Decade John Napier Level Logarithm Logarithmic mean Preferred number Dehaene, Izard, Véronique, Elizabeth, distinct intuitions of the number scale in Western and Amazonian indigene cultures.
American Association for the Advancement of Science, why using logarithmic scale to display share prices
Mineral dust is a term used to indicate atmospheric aerosols originated from the suspension of minerals constituting the soil, being composed of various oxides and carbonates. Human activities lead to 30% of the dust load in the atmosphere, the Sahara Desert is the major source of mineral dust, which subsequently spreads across the Mediterranean and Caribbean seas into northern South America, Central America, North America, and Europe. Additionally, it plays a significant role in the nutrient inflow to the Amazon rainforest, the Gobi Desert is another source of dust in the atmosphere, which affects eastern Asia and western North America. Mineral dust is mainly constituted of the oxides and carbonates that constitute the Earths crust, global mineral dust emissions are estimated at 1000-5000 millions of tons per year, of which the largest part is attributed to deserts. Large dust concentrations may cause problems to people having respiratory problems, another effect of dust clouds is more colorful sunsets.
The Sahara is the source on Earth of mineral dust. There is a variability in the dust transport across the Atlantic into the Caribbean. Saharan plumes can form iberulites when these plumes travel through North Africa and the eastern North Atlantic Ocean, in the Mediterranean region, Saharan dust is important as it represents the major source of nutrients for phytoplankton and other aquatic organisms. Saharan dust carries the fungus Aspergillus sydowii and others, Aspergillus borne by Saharan dust falls into the Caribbean Sea and possibly infects coral reefs with Sea Fan disease. It has been linked to increased incidence of asthma attacks in the Caribbean. Since 1970, dust outbreaks have worsened due to periods of drought in Africa, dust events have been linked to a decline in the health of coral reefs across the Caribbean and Florida, primarily since the 1970s. There were only 5 hurricanes in 2006 and compared with 15 in 2005 and it is known that one of the major factors that create hurricanes is warm water temperatures on the surface of the ocean.
Evidence shows that dust from the Sahara desert caused surface temperatures to be cooler in 2006 than in 2005, in Eastern Asia, mineral dust events originated in springtime in the Gobi Desert gives rise to the phenomenon called Asian dust. The aerosols are carried eastward by prevailing winds, and pass over China, sometimes, significant concentrations of dust can be carried as far as the Western United States. Areas affected by Asian dust experience decreased visibility and health problems, such as sore throat, the effects of Asian dust, are not strictly negative, as it is thought that its deposition enrichs the soil with important trace minerals. Morales, The airborne transport of Saharan dust, a review, Climate Change 9, influence of Saharan dust on the rain acidity and atmospheric input to the Mediterranean, Nature 321, 427-428. Sokolik and Toon, Direct radiative forcing by anthropogenic airborne mineral aerosols, Nature 381, tegen and Fung, Contribution to the atmospheric mineral aerosol load from land surface modification, Journal of Geophysical Research 100, 18707-18726. Yücekutlu, N.
Terzioğlu, S. Saydam, C. and Bildacı, organic Farming By Using Saharan Soil, Could It Be An Alternative To Fertilizers
A crystal or crystalline solid is a solid material whose constituents are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macroscopic single crystals are usually identifiable by their geometrical shape, the scientific study of crystals and crystal formation is known as crystallography. The process of crystal formation via mechanisms of crystal growth is called crystallization or solidification, the word crystal derives from the Ancient Greek word κρύσταλλος, meaning both ice and rock crystal, from κρύος, icy cold, frost. Examples of large crystals include snowflakes and table salt, most inorganic solids are not crystals but polycrystals, i. e. many microscopic crystals fused together into a single solid. Examples of polycrystals include most metals, ceramics, a third category of solids is amorphous solids, where the atoms have no periodic structure whatsoever. Examples of amorphous solids include glass and many plastics, Crystals are often used in pseudoscientific practices such as crystal therapy, along with gemstones, are sometimes associated with spellwork in Wiccan beliefs and related religious movements.
The scientific definition of a crystal is based on the arrangement of atoms inside it. A crystal is a solid where the form a periodic arrangement. For example, when liquid water starts freezing, the change begins with small ice crystals that grow until they fuse. Most macroscopic inorganic solids are polycrystalline, including almost all metals, ice, solids that are neither crystalline nor polycrystalline, such as glass, are called amorphous solids, called glassy, vitreous, or noncrystalline. These have no periodic order, even microscopically, there are distinct differences between crystalline solids and amorphous solids, most notably, the process of forming a glass does not release the latent heat of fusion, but forming a crystal does. A crystal structure is characterized by its cell, a small imaginary box containing one or more atoms in a specific spatial arrangement. The unit cells are stacked in three-dimensional space to form the crystal, the symmetry of a crystal is constrained by the requirement that the unit cells stack perfectly with no gaps.
There are 219 possible crystal symmetries, called space groups. These are grouped into 7 crystal systems, such as cubic crystal system or hexagonal crystal system, Crystals are commonly recognized by their shape, consisting of flat faces with sharp angles. Euhedral crystals are those with obvious, well-formed flat faces, anhedral crystals do not, usually because the crystal is one grain in a polycrystalline solid. The flat faces of a crystal are oriented in a specific way relative to the underlying atomic arrangement of the crystal. This occurs because some surface orientations are more stable than others, as a crystal grows, new atoms attach easily to the rougher and less stable parts of the surface, but less easily to the flat, stable surfaces
Nash Point is a headland and beach in the Monknash Coast of the Vale of Glamorgan in south Wales, about a mile from Marcross. It is a location for ramblers and hiking along the cliffs to Llantwit Major beach. The lighthouse meadow is a Site of Special Scientific Interest, containing plants such as the tuberous thistle. Many fossils, including ammonites and gryphaea are to be found there, Marcross Brook passes through the cliffs and an Iron Age hillfort, usually called Nash Point Camp, stands on the north side of the brook, although its remains have been largely eroded by the sea. Round barrows are to be found nearby, in 1962, the empty tanker BP Driver was pushed on the rocks and was abandoned by its crew of five, all of whom survived. Despite the assistance given by the lighthouse, the captain was unable to bring her in safely to land. At low tide, remains of the wreck can be found about 200m north of the access by the light house. The Nash Point Lighthouse is a Grade II listed building, dating from 1831-32, there are two lights, a high light and a low light, located at a distance of around 300 metres from one another.
The leading light was removed during the 1920s because of the location of the Nash sandbank. The lighthouse was designed by James Walker, the engineer for Trinity House. Its construction is said to have been spurred by the wreck of The Frolic on the Nash Sands in March 1831, the ship was on its way from Bristol to Haverfordwest. First lit in 1832, the lighthouse was electrified in 1968, Nash Point Lighthouse became the last manned lighthouse in Wales, and was automated in 1998. The lighthouse is now open to visitors, and is used as a wedding venue. The fog signal, no longer needed by ships, is sounded on the first Saturday, cottages around the lighthouse can be rented out as holiday accommodation. List of lighthouses in Wales Information and photos Trinity House
Clastic rocks are composed of fragments, or clasts, of pre-existing minerals and rock. A clast is a fragment of geological detritus and smaller grains of rock broken off other rocks by physical weathering. Geologists use the term clastic with reference to sedimentary rocks as well as to particles in sediment transport whether in suspension or as bed load, clastic sedimentary rocks are rocks composed predominantly of broken pieces or clasts of older weathered and eroded rocks. Clastic sediments or sedimentary rocks are classified based on size and cementing material composition. The classification factors are often useful in determining a samples environment of deposition, an example clastic environment would be a river system in which the full range of grains being transported by the moving water consist of pieces eroded from solid rock upstream. Grain size varies from clay in shales and claystones, through silt in siltstones, sand in sandstones, the Krumbein phi scale numerically orders these terms in a logarithmic size scale.
Siliciclastic rocks are clastic rocks that are composed almost exclusively of silicon. The composition of sedimentary rocks includes the chemical and mineralogical components of the framework as well as the cementing material that make up these rocks. Boggs divides them into four categories, major minerals, accessory minerals, rock fragments, major minerals can be categorized into subdivisions based on their resistance to chemical decomposition. Those that possess a great resistance to decomposition are categorized as stable, while those that do not are considered less stable, the most common stable mineral in siliciclastic sedimentary rocks is quartz. Quartz makes up approximately 65 percent of framework grains present in sandstones, less stable minerals present in this type of rocks are feldspars, including both potassium and plagioclase feldspars. Feldspars comprise a considerably lesser portion of framework grains and minerals and they only make up about 15 percent of framework grains in sandstones and 5% of minerals in shales.
Clay mineral groups are present in mudrocks but can be found in other siliciclastic sedimentary rocks at considerably lower levels. Accessory minerals are associated with those whose presence in the rock are not directly important to the classification of the specimen and these generally occur in smaller amounts in comparison to the quartz, and feldspars. Furthermore, those that do occur are generally heavy minerals or coarse grained micas, rock fragments occur in the composition of siliciclastic sedimentary rocks and are responsible for about 10 -15 percent of the composition of sandstone. They generally make up most of the gravel size particles in conglomerates, though they sometimes are, rock fragments are not always sedimentary in origin. They can be metamorphic or igneous, chemical cements vary in abundance but are predominantly found in sandstones. The two major types, are based and carbonate based
Gravel /ˈɡrævəl/ is composed of unconsolidated rock fragments that have a general particle size range and include size classes from granule- to boulder-sized fragments. Gravel is categorized by the Udden-Wentworth scale into granular gravel and pebble gravel, one cubic metre of gravel typically weighs about 1,800 kg. Gravel is an important commercial product, with a number of applications, many roadways are surfaced with gravel, especially in rural areas where there is little traffic. Globally, far more roads are surfaced with gravel than with concrete or tarmac, both sand and small gravel are important for the manufacture of concrete. Large gravel deposits are a geological feature, being formed as a result of the weathering. The action of rivers and waves tends to pile up gravel in large accumulations and this can sometimes result in gravel becoming compacted and concreted into the sedimentary rock called conglomerate. Where natural gravel deposits are insufficient for human purposes, gravel is often produced by quarrying and crushing hard-wearing rocks, such as sandstone, quarries where gravel is extracted are known as gravel pits.
Southern England possesses particularly large concentrations of them due to the deposition of gravel in the region during the Ice Ages. As of 2006, the United States is the leading producer and consumer of gravel. The word gravel comes from the Breton language, adding the -el suffix in Breton denotes the component parts of something larger. Thus gravel means the stones which make up such a beach on the coast. Many dictionaries ignore the Breton language, citing Old French gravele or gravelle, Gravel often has the meaning a mixture of different size pieces of stone mixed with sand and possibly some clay. American English allows small stones without sand mixed in known as crushed stone, types of gravel include, Bank gravel, naturally deposited gravel intermixed with sand or clay found in and next to rivers and streams. Also known as Bank run or River run, bench gravel, a bed of gravel located on the side of a valley above the present stream bottom, indicating the former location of the stream bed when it was at a higher level.
Creek rock, this is rounded, semi-polished stones, potentially of a wide range of types. It is used as concrete aggregate and less often as a paving surface. Crushed stone, rock crushed and graded by screens and mixed to a blend of stones and fines and it is widely used as a surfacing for roads and driveways, sometimes with tar applied over it. Crushed stone may be made from granite, dolomite, known as crusher run, DGA QP, and shoulder stone
Soil texture is known as a qualitative classification instrument used both in the field and laboratory for agricultural soils to determine classes based on their physical texture. As a qualitative rather than a tool it is a fast, simple. The USDA soil taxonomy and WRB soil classification systems use 12 classes whereas the UK-ADAS system uses just 11, hand analysis is a simple and effective means to rapidly assess and classify a soils physical condition. Correctly executed, the procedure allows for rapid and frequent assessment of soil characteristics with little or no equipment and it is thus an extremely useful tool for identifying spatial variation both within and between plots as well as identifying progressive changes and boundaries between soil classes and orders. The method involves taking a sample of soil, sufficient to roll into a ball of approx 2.5 cm diameter. Using a small drop of water or spit the sample is moistened to the sticky point, the ball is molded to determine its work ability and its class according to the steps in the chart opposite.
Soil separates are specific ranges of particle sizes, the next smallest particles are silt particles and have diameters between 0.002 mm and 0.05 mm. The largest particles are sand particles and are larger than 0.05 mm in diameter, large sand particles can be described as coarse, intermediate as medium, and the smaller as fine. Other countries have their own particle size classifications, Soil textures are classified by the fractions of each soil separate present in a soil. Classifications are typically named for the primary constituent particle size or a combination of the most abundant particles sizes, e. g. sandy clay or silty clay. A fourth term, loam, is used to describe a roughly equal concentration of sand and clay, in the United States, twelve major soil texture classifications are defined by the USDA. Determining the soil textures is often aided with the use of a soil texture triangle and physical properties of a soil are related to texture. Particle size and distribution will affect a soils capacity for holding water, fine textured soils generally have a higher capacity for water retention, whereas sandy soils contain large pore spaces that allow leaching.
The first classification, the International system, was first proposed by Albert Atterberg, Commission One of the International Society of Soil Science recommended its use at the first International Congress of Soil Science in Washington in 1927. Australia adopted this system and according to Marshall its equal logarithmic intervals are a feature worth maintaining. The USDA adopted its own system in 1938, and the FAO used the USDA system in the FAO-UNESCO world soil map, Soil color Texture Soil Texture, by R. B. Brown, University of Florida, Institute of Food and Agricultural Sciences, Atterberg A Die rationalle Klassifikation der Sande und Kiese. Davis ROE, Bennett HH Grouping of soils on the basis of mechanical analysis, United States Department of Agriculture Departmental Circulation No.419
A granular material is a conglomeration of discrete solid, macroscopic particles characterized by a loss of energy whenever the particles interact. The constituents that compose granular material must be large enough such that they are not subject to thermal motion fluctuations, the lower size limit for grains in granular material is about 1 µm. Some examples of materials are snow, coal, rice, corn flakes, fertilizer. Powders are a class of granular material due to their small particle size. Granular materials are important in applications as diverse as pharmaceutical industry, agriculture. Research into granular materials is thus directly applicable and goes back at least to Charles-Augustin de Coulomb, according to material scientist Patrick Richard, Granular materials are ubiquitous in nature and are the second-most manipulated material in industry. In some sense, granular materials do not constitute a phase of matter but have characteristics reminiscent of solids, liquids. However, in each of these states granular materials exhibit properties which are unique, Granular materials exhibit a wide range of pattern forming behaviors when excited.
As such granular materials under excitation can be thought of as an example of a complex system, when the average energy of the individual grains is low and the grains are fairly stationary relative to each other, the granular material acts like a solid. In general, stress in a solid is not distributed uniformly but is conducted away along so-called force chains which are networks of grains resting on one another. Between these chains are regions of low stress whose grains are shielded for the effects of the grains above by vaulting and arching, if the granular material is driven harder such that contacts between the grains become highly infrequent, the material enters a gaseous state. Correspondingly, one can define a granular temperature equal to the mean square of grain velocity fluctuations that is analogous to thermodynamic temperature. Unlike conventional gases, granular materials will tend to cluster and clump due to the nature of the collisions between grains and this clustering has some interesting consequences.
This effect, known as the granular Maxwells demon, does not violate any thermodynamics principles since energy is constantly being lost from the system in the process. Granular systems are known to exhibit jamming and undergo a transition which is thought of as a thermodynamic phase transition to a jammed state. The Lubachevsky-Stillinger algorithm of jamming allows one to produce simulated jammed granular configurations, excited granular matter is a rich pattern-forming system. Some of the pattern-forming behaviours seen in granular materials are, The un-mixing or segregation of unlike grains under vibration, Some larger materials get stuck while going down the circle and therefore stay on the top. The formation of surface patterns in vibrated granular layers and these patterns include but are not limited to stripes and hexagons
In geology, a boulder is a rock fragment with size greater than 25.6 centimetres in diameter. Smaller pieces are called cobbles and pebbles, while a boulder may be small enough to move or roll manually, others are extremely massive. In common usage, a boulder is too large for a person to move, smaller boulders are usually just called rocks or stones. The word boulder is short for boulder stone, from Middle English bulderston or Swedish bullersten, in places covered by ice sheets during Ice Ages, such as Scandinavia, northern North America, and Siberia, glacial erratics are common. Erratics are boulders picked up by ice sheets during their advance and they are called erratic because they typically are of a different rock type than the bedrock on which they are deposited. One of them is used as the pedestal of the Bronze Horseman in Saint Petersburg, boulder sized clasts are found in some sedimentary rocks, such as coarse conglomerate and boulder clay. The climbing of large boulders is called bouldering, road debris Monolith Media related to Boulders at Wikimedia Commons
Sand is a naturally occurring granular material composed of finely divided rock and mineral particles. It is defined by size, being finer than gravel and coarser than silt, Sand can refer to a textural class of soil or soil type, i. e. a soil containing more than 85% sand-sized particles by mass. The second most common type of sand is calcium carbonate, for example aragonite, for example, it is the primary form of sand apparent in areas where reefs have dominated the ecosystem for millions of years like the Caribbean. Sand is a non renewable resource over human timescales, and sand suitable for making concrete is in high demand, in terms of particle size as used by geologists, sand particles range in diameter from 0.0625 mm to 2 mm. An individual particle in this size is termed a sand grain. Sand grains are between gravel and silt, a 1953 engineering standard published by the American Association of State Highway and Transportation Officials set the minimum sand size at 0.074 mm. A1938 specification of the United States Department of Agriculture was 0.05 mm.
Sand feels gritty when rubbed between the fingers. ISO14688 grades sands as fine and coarse with ranges 0.063 mm to 0.2 mm to 0.63 mm to 2.0 mm. In the United States, sand is commonly divided into five sub-categories based on size, very fine sand, fine sand, medium sand, coarse sand, and very coarse sand. These sizes are based on the Krumbein phi scale, where size in Φ = -log2D, on this scale, for sand the value of Φ varies from −1 to +4, with the divisions between sub-categories at whole numbers. The composition of sand is highly variable, depending on the local rock sources. The gypsum sand dunes of the White Sands National Monument in New Mexico are famous for their bright, arkose is a sand or sandstone with considerable feldspar content, derived from weathering and erosion of a granitic rock outcrop. Some sands contain magnetite, glauconite or gypsum, Sands rich in magnetite are dark to black in color, as are sands derived from volcanic basalts and obsidian. Chlorite-glauconite bearing sands are typically green in color, as are sands derived from basaltic with a high olivine content, many sands, especially those found extensively in Southern Europe, have iron impurities within the quartz crystals of the sand, giving a deep yellow color.
Sand deposits in some areas contain garnets and other resistant minerals, the study of individual grains can reveal much historical information as to the origin and kind of transport of the grain. Quartz sand that is weathered from granite or gneiss quartz crystals will be angular. It is called grus in geology or sharp sand in the trade where it is preferred for concrete. Sand that is transported long distances by water or wind will be rounded, people who collect sand as a hobby are known as arenophiles