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Radiation Law For Human Mobility
The radiation law is way of modeling human mobility ( geographic mobility, human migration) and it gives better empirical predictions than the gravity model of migration which is widely used in this subject. Intercity mobility Waves of migration due to displacement by war, or exploitation in the hope of geographical discoveries could be observed in the past, however with new technological advancements in transportation keep making it easier and cheaper to get to one place from another. With intercontinental flights we even can travel to another continent, on a business trip for instance, and come back within a few hours. Not only time but road networks and flight networks are being used more and more intensively also, and there is an increasing need to describe the patterns of human peoples' mobility and their effect on network usage, whether the network is a transportation, communication or some other type of network. The radiation model Source: Radiation models appeared fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gravity Model Of Trade
The gravity model of international trade in international economics is a model that, in its traditional form, predicts bilateral trade flows based on the economic sizes and distance between two units. Research shows that there is "overwhelming evidence that trade tends to fall with distance." The model was first introduced by Walter Isard in 1954, who elaborated the concept of "income potential" within the framework of international economics, building upon John Quincy Stewart's earlier idea of demographic gravitation, which had been introduced in 1941. Similarly, Stewart's work on population potential from 1947 had a significant impact on Chauncy Harris, who, in 1954, proposed the economic concept of market potential. The basic model for trade between two countries (''i'' and ''j'') takes the form of : F_ = G \cdot \frac. In this formula G is a constant, F stands for trade flow, D stands for the distance and M stands for the economic dimensions of the countries that are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wave Propagation
In physics, mathematics, engineering, and related fields, a wave is a propagating dynamic disturbance (change from equilibrium) of one or more quantities. '' Periodic waves'' oscillate repeatedly about an equilibrium (resting) value at some frequency. When the entire waveform moves in one direction, it is said to be a travelling wave; by contrast, a pair of superimposed periodic waves traveling in opposite directions makes a '' standing wave''. In a standing wave, the amplitude of vibration has nulls at some positions where the wave amplitude appears smaller or even zero. There are two types of waves that are most commonly studied in classical physics: mechanical waves and electromagnetic waves. In a mechanical wave, stress and strain fields oscillate about a mechanical equilibrium. A mechanical wave is a local deformation (strain) in some physical medium that propagates from particle to particle by creating local stresses that cause strain in neighboring particles too ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Social Theories
Social theories are analytical frameworks, or paradigms, that are used to study and interpret social phenomenon, social phenomena.Seidman, S., 2016. Contested knowledge: Social theory today. John Wiley & Sons. A tool used by social scientists, social theories relate to historical debates over the validity and reliability of different methodology, methodologies (e.g. positivism and antipositivism), the primacy of either structure or agency, as well as the relationship between contingency (philosophy), contingency and necessity. Social theory in an informal nature, or authorship based outside of academic social and political science, may be referred to as "social criticism" or "social commentary", or "cultural criticism" and may be associated both with formal cultural studies, cultural and literary criticism, literary scholarship, as well as other non-academic or journalistic forms of writing. Definitions Social theory by definition is used to make distinctions and generalizati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Alonso
William Alonso (January 29, 1933 – February 11, 1999) was an Argentine- American planner and economist. He was born in Buenos Aires but moved to the United States in 1946 during the Perón regime with his father Amado Alonso, a leading Spanish philologist, who was then appointed at Harvard. He earned a bachelor's degree in architectural science from Harvard in 1954 and a master's degree in city planning from Harvard University's Graduate School of Public Administration in 1956. In 1960 he received a doctorate in regional science from the University of Pennsylvania. From 1960 to 1961 Alonso worked as director and professor in the Department of Regional and Urban Planning at the Bandung Institute of Technology in Indonesia. He then served as a visiting professor at the Universidad Central de Venezuela in 1962 before coming to Harvard as the acting director of the Center of Urban Studies from 1963 to 1965. Alonso also worked at Yale University, the University of California at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alabama
Alabama ( ) is a U.S. state, state in the Southeastern United States, Southeastern and Deep South, Deep Southern regions of the United States. It borders Tennessee to the north, Georgia (U.S. state), Georgia to the east, Florida and the Gulf of Mexico to the south, and Mississippi to the west. Alabama is the List of U.S. states and territories by area, 30th largest by area, and the List of U.S. states and territories by population, 24th-most populous of the List of states and territories of the United States, 50 U.S. states. Alabama is nicknamed the ''Northern flicker, Yellowhammer State'', after the List of U.S. state birds, state bird. Alabama is also known as the "Heart of Dixie" and the "Cotton State". The state has diverse geography, with the north dominated by the mountainous Tennessee Valley and the south by Mobile Bay, a historically significant port. Alabama's capital is Montgomery, Alabama, Montgomery, and its largest city by population and area is Huntsville, Ala ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Utah
Utah is a landlocked state in the Mountain states, Mountain West subregion of the Western United States. It is one of the Four Corners states, sharing a border with Arizona, Colorado, and New Mexico. It also borders Wyoming to the northeast, Idaho to the north, and Nevada to the west. In comparison to all the U.S. states and territories, Utah, with a population of just over three million, is the List of U.S. states and territories by area, 13th largest by area, the List of U.S. states and territories by population, 30th most populous, and the List of U.S. states by population density, 11th least densely populated. Urban development is mostly concentrated in two regions: the Wasatch Front in the north-central part of the state, which includes the state capital, Salt Lake City, and is home to roughly two-thirds of the population; and Washington County, Utah, Washington County in the southwest, which has approximately 180,000 residents. Most of the western half of Utah lies in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flux
Flux describes any effect that appears to pass or travel (whether it actually moves or not) through a surface or substance. Flux is a concept in applied mathematics and vector calculus which has many applications in physics. For transport phenomena, flux is a vector quantity, describing the magnitude and direction of the flow of a substance or property. In vector calculus flux is a scalar quantity, defined as the surface integral of the perpendicular component of a vector field over a surface. Terminology The word ''flux'' comes from Latin: ''fluxus'' means "flow", and ''fluere'' is "to flow". As '' fluxion'', this term was introduced into differential calculus by Isaac Newton. The concept of heat flux was a key contribution of Joseph Fourier, in the analysis of heat transfer phenomena. His seminal treatise ''Théorie analytique de la chaleur'' (''The Analytical Theory of Heat''), defines ''fluxion'' as a central quantity and proceeds to derive the now well-known expre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commuting
Commuting is periodically recurring travel between a place of residence and place of work or study, where the traveler, referred to as a commuter, leaves the boundary of their home community. By extension, it can sometimes be any regular or often repeated travel between locations, even when not work-related. The modes of travel, time taken and distance traveled in commuting varies widely across the globe. Most people in least-developed countries continue to walk to work. The cheapest method of commuting after walking is usually Bicycle commuting, by bicycle, so this is common in low-income countries but is also increasingly practised by people in wealthier countries for environmental, health, and often time reasons. In middle-income countries, motorcycle commuting is very common. The next technology adopted as countries develop is more dependent on location: in more populous, older cities, especially in Eurasia mass transit (rail, bus, etc.) predominates, while in smaller, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Social Science
Social science (often rendered in the plural as the social sciences) is one of the branches of science, devoted to the study of societies and the relationships among members within those societies. The term was formerly used to refer to the field of sociology, the original "science of society", established in the 18th century. It now encompasses a wide array of additional academic disciplines, including anthropology, archaeology, economics, geography, history, linguistics, management, communication studies, psychology, culturology, and political science. The majority of positivist social scientists use methods resembling those used in the natural sciences as tools for understanding societies, and so define science in its stricter modern sense. Speculative social scientists, otherwise known as interpretivist scientists, by contrast, may use social critique or symbolic interpretation rather than constructing empirically falsifiable theories, and thus treat science in its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiation
In physics, radiation is the emission or transmission of energy in the form of waves or particles through space or a material medium. This includes: * ''electromagnetic radiation'' consisting of photons, such as radio waves, microwaves, infrared, visible light, ultraviolet, x-rays, and Gamma ray, gamma radiation (γ) * ''particle radiation'' consisting of particles of non-zero rest energy, such as alpha radiation (α), beta radiation (β), proton radiation and neutron radiation * ''acoustics, acoustic radiation'', such as ultrasound, sound, and seismic waves, all dependent on a physical transmission medium * ''gravitational radiation'', in the form of gravitational waves, ripples in spacetime Radiation is often categorized as either ''ionizing radiation, ionizing'' or ''non-ionizing radiation, non-ionizing'' depending on the energy of the radiated particles. Ionizing radiation carries more than 10 electron volt, electron volts (eV), which is enough to ionize atoms and molecul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geographic Mobility
Geographic mobility is the measure of how populations and goods move over time. Geographic mobility, population mobility, or more simply mobility is also a statistic that measures migration within a population. Commonly used in demography and human geography, it may also be used to describe the movement of animals between populations. These moves can be as large scale as international migrations or as small as regional commuting arrangements. Geographic mobility has a large impact on many sociological factors in a community and is a current topic of academic research.Population Mobility:Migration in a Global Economy (2013). Harvard College. It varies between different regions depending on both formal policies and established social norms, and has different effects and responses in different societies. Population mobility has implications ranging from administrative changes in government and impacts on local economic growth to housing markets and demand for regional services. M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Network Theory
In mathematics, computer science, and network science, network theory is a part of graph theory. It defines networks as Graph (discrete mathematics), graphs where the vertices or edges possess attributes. Network theory analyses these networks over the symmetric relations or directed graph, asymmetric relations between their (discrete) components. Network theory has applications in many disciplines, including statistical physics, particle physics, computer science, electrical engineering, biology, archaeology, linguistics, economics, finance, operations research, climatology, ecology, public health, sociology, psychology, and neuroscience. Applications of network theory include Logistics, logistical networks, the World Wide Web, Internet, gene regulatory networks, metabolic networks, social networks, epistemological networks, etc.; see List of network theory topics for more examples. Euler's solution of the Seven Bridges of Königsberg, Seven Bridges of Königsberg problem is c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
