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Radiative transfer - The research frontiers of radiative transfer (RT) in coupled at

In such relations, h ¯ c is the average convection heat transfer coe

May 22, 2019 · Stefan–Boltzmann Law. Radiation heat transfer rate, q [W/m 2 ], from a body (e.g. a black body) to its surroundings is proportional to the fourth power of the absolute temperature and can be expressed by the following equation: q = εσT4. where σ is a fundamental physical constant called the Stefan–Boltzmann constant, which is equal to 5. ... on shortwave radiation using a 3D radiative transfer model J. Atmos. Solar-Terrestrial Phys., 204, 105287, doi: 10.1016/j.jastp.2020.105287. [Full paper] 2019 Crnivec, N. and B. Mayer, 2019: Quantifying the bias of radiative heating rates in numerical weather Radiative forcing for doubling CO 2, as calculated by radiative transfer code Modtran. Red lines are Planck curves. For a well-mixed greenhouse gas, radiative transfer codes that examine each spectral line for atmospheric conditions can be used to calculate the forcing ΔF as a function of a change in its concentration. These calculations may ...Apr 15, 2013 · Subrahmanyan Chandrasekhar. Courier Corporation, Apr 15, 2013 - Science - 416 pages. " Radiative Transfer is the definitive work in the field. It provides workers and students in physics, nuclear physics, astrophysics, and atmospheric studies with the foundation for the analysis of stellar atmospheres, planetary illumination, and sky radiation. Different names are used for electromagnetic waves of different wavelengths: radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, X-rays, and gamma rays. Figure 14.7.1 14.7. 1: Most of the heat transfer from this fire to the observers is through infrared radiation. The visible light, although dramatic, transfers ...The transfer of solar and infrared radiation through optically-thick clouds, aerosol layer, and the oceanic mixed layer is presented through the use of heuristic models of scattering and absorption, and a systematic approach to formulation and solution of the radiative transfer equation. Problems such as the the transmission of ultraviolet ...Radiative transfer theory. The study of the passage of electromagnetic radiation, gamma rays, neutrons, etc., through matter, examined by means of a linear kinetic equation or transport equation (see Kinetic equation ). The problem of the determination of the radiation field in the atmosphere and the scattering of light in accordance with known ...Radiative transfer is the study of how light interacts with gases and particles in our atmosphere. Remote sensing is the study of how to use this interaction, or lack thereof, to extract information about the state of the atmosphere or the surface interacting with it. Incoming shortwave radiation from the sun can be absorbed or scattered in the ...Radiative transfer is the study of how light interacts with gases and particles in our atmosphere. Remote sensing is the study of how to use this interaction, or lack thereof, to extract information about the state of the atmosphere or the surface interacting with it. Incoming shortwave radiation from the sun can be absorbed or scattered in the ... Review of Basic Thermal Radiation Concepts, Blackbody Radiation 2 View Factor, Simple Radiative Transfer Week 2: 3 Radiative Transfer in Enclosures 4 Radiative Transfer in Enclosures (cont.) Week 3: 5 EM Waves Week 4: 6 EM Wave Modeling of Surfaces 7 EM Wave Modeling of Thin FilmsAbstract A systematic formulation of various radiative transfer parameterizations is presented, including the absorption approximation (AA), δ-two-stream approximation (D2S), δ-four-stream approximation (D4S), and δ-two- and four-stream combination approximation (D2/4S), in a consistent manner for thermal infrared flux …However, since 3D radiative transfer calculations are computationally expensive, efficient methods need to be developed for operational applications that provide an appropriate balance between accuracy and computational cost. To fully benefit from 3D-box AMFs, 3D radiative transfer calculations require high-resolution 3D distributions of trace gases …We discuss the architecture and design principles that underpin the latest version of SKIRT, a state-of-the-art open source code for simulating continuum radiation transfer in dusty astrophysical systems, such as spiral galaxies and accretion disks. SKIRT employs the Monte Carlo technique to emulate the relevant physical processes including scattering, absorption and emission by the dust. The ...Download PDF Abstract: We explore near-field radiative heat transfer between two bodies under time modulation by developing a rigorous fluctuational …Results of an extensive validation study of the new radiative transfer code SHARM-3D are described. The code is designed for modeling of unpolarized monochromatic radiative transfer in the visible and near-IR spectra in the laterally uniform atmosphere over an arbitrarily inhomogeneous anisotropic surface.Radiative transfer (also called radiation transport) is the physical phenomenon of energy transfer in the form of electromagnetic radiation. The propagation of radiation through a medium is affected by absorption , emission , and scattering processes.More information: Yang Xiao-lin et al, A New Fast Monte Carlo Code for Solving Radiative Transfer Equations Based on the Neumann Solution, The Astrophysical Journal Supplement Series (2021). DOI ...Description. The third edition of Radiative Heat Transfer describes the basic physics of radiation heat transfer. The book provides models, methodologies, and calculations essential in solving research problems in a variety of industries, including solar and nuclear energy, nanotechnology, biomedical, and environmental.While the radiative transfer can be constrained to one or more narrow bands (at a single wavelength maximal transfer of radiation between two bodies can be achieved, as the optical transmission coefficient can reach unity), for instance due to polariton resonance(s), this can lead to reducing the exchanged power to a minute value. The Bose–Einstein …Transferring pictures from your iPhone to your PC can be a daunting task, especially if you’re not tech savvy. Fortunately, there are several easy ways to do this. In this comprehensive guide, we will cover the three most popular methods of...Radiative transfer Bookreader Item Preview remove-circle Share or Embed This Item. Share to Twitter. Share to Facebook. Share to Reddit. Share to Tumblr. Share to Pinterest. Share via email. EMBED. EMBED (for wordpress.com hosted blogs and archive.org item <description> tags) Want more? Advanced embedding details, examples, and help! …Topics. Review of Basic Thermal Radiation Concepts, Blackbody Radiation. Near Field Thermal Radiation, Fluctuation-dissipation Theory. This section lists the various topics covered during the course along with two sets of lecture notes files, one by the professor and one by a student.Chandrasekhar's work in radiative transfer theory began in 1944 and culminated with the publication of his influential treatiseRadiative Transfer in 1950. In this review his major contributions to radiative transfer will be recounted and evaluated. These include his development of the discrete ordinates method, the invariance principles, and his formulation and solution of the transfer ...Radiation is responsible for most of the heat transferred into the room. Heat transfer also occurs through conduction into the room, but much slower. Heat transfer by convection also occurs through cold air entering the room around windows and hot air leaving the room by rising up the chimney. Exercise 1.7.1.Radiative Forcings. Atmospheric radiative transfer is the science of understanding how electromagnetic radiation emitted by both the Sun and Earth interacts with the gases, clouds and particles making up our atmosphere. The changes in energy due to these interactions are responsible for many variations in temperature and weather that we ...In this paper, we present two machine learning algorithms to identify D mesons produced in a colour singlet state from radiative W boson decays at the LHC. …Radiative transfer modelling. The purpose of the activity is the implementation and development of algorithms for the atmospheric radiative transfer ...Linelist: Capabilities: Reference: PUMAS Planetary and Universal Model of Atmospheric Scattering: PUMAS integrates the latest radiative-transfer methods and spectroscopic parameterizations, in order to compute high resolution spectra via line-by-line calculations, and utilizes the efficient correlated-k method at moderate resolutions.The radiative transfer equation to be solved under a typical solid fuel combustor is presented in Eq. (4.2), in which the gas and particle radiative properties are evaluated by Eq. (4.3)-(4.5), respectively.The total gas emissivity of a local gas mixture to be used in Eq. (4.3), ε, is commonly evaluated by a WSGGM in combustion CFD because it is a good compromise between computational ...IDOT: OVERVIEW OF THE STATUS OF RADIATIVE TRANSFER MODELS FOR SATELLITE DATA ASSIMILATION ECMWF Seminar on the Use of Satellite Observations in NWP, 8-12 September 2014 3 The differential change of monochromatic radiance (at wavenumber dR) along the path ν ds within an atmospheric layer of thickness dz in the direction given by spherical coordinates (θ, ϕ) is given by:Radiative Transfer. Propagation of Radiation We have discussed the generation of radiation by considering the volume emissivity, η ν, which is the energy per unit time per unit volume per unit frequency bandwidth per sterradian. Note that these units are the same as intensity, except it is per unit volume instead of per unit area.SBDART is a software tool that computes plane-parallel radiative transfer in clear and cloudy conditions within the earth's atmosphere and at the surface. All important processes that affect the ultraviolet, visible, and infrared radiation fields are included. The code is a marriage of a sophisticated discrete ordinate radiative transfer module, low-resolution atmospheric transmission models ...Radiative Transfer Equation. Radiance is defined as energy flow per unit normal area per unit solid angle per unit time. Here, r→ denotes position, s^ denotes unit direction vector and t denotes time (Figure 1). Several other important physical quantities are based on the definition of radiance:After several decades’ development of retrieval techniques in aerosol remote sensing, no fast and accurate analytical Radiative Transfer Model (RTM) has been developed and applied to create global aerosol products for non-polarimetric instruments such as Ocean and Land Colour Instrument/Sentinel-3 (OLCI/Sentinel-3) and Meteosat Second Generation/Spinning Enhanced Visible and Infrared Imager ...The here presented Automated Radiative Transfer Models Operator (ARTMO) Graphic User Interface (GUI) software package provides a seamless link between inputs and outputs required for running a suite of reflectance models both at the leaf level and at the canopy level. ARTMO facilitates consistent and intuitive user interaction, thereby ...@article{osti_249636, title = {Two-flux and diffusion methods for radiative transfer in composite layers}, author = {Spuckler, C M and Siegel, R}, abstractNote = {Temperature distributions and heat fluxes are predicted in composite semitransparent layers heated or cooled on both sides by radiation and convection. Two approximate methods were used for performing spectral calculations, and the ...This book is a valuable resource for researchers in the field of radiative transfer theory whose interests transcend the physical and numerical aspects of the interaction of light with matter. Show less. Pure and Applied Mathematics, Volume 74: Radiative Transfer on Discrete Spaces presents the geometrical structure of natural light fields. ...An Introduction to Radiative Transfer presents these techniques as applied to stellar atmospheres, planetary nebulae, supernovae, and other objects with similar geometrical and physical conditions. Accurate methods, fast methods, probabilistic methods and approximate methods are all explained, including the latest and most advanced techniques.Abstract Demands for Monte Carlo radiative transfer modeling have grown with the increase in computational power in recent decades. This method provides realistic simulations of radiation processes for various types of application, including radiation budgets in cloudy conditions and remote measurements of clouds, aerosols, and gases. …Jan 1, 2015 · Radiative transfer is the theory describing how electromagnetic radiation is created, transmitted, absorbed, and scattered in a medium such as a planetary atmosphere, stellar photosphere, or interstellar medium. The medium can emit, absorb, and scatter radiation with a behavior that could vary strongly with wavelength according to the different ... The radiative transfer models developed at AER are being used extensively for a wide range of applications in the atmospheric sciences. This communication is intended to provide a coherent summary ...The radiative transfer equation (RTE), which describes the propagation of radiation energy in participating media, plays an important role in many scientific and engineering fields, such as atmospheric radiative transfer [1], optical tomography [2], astrophysics [3], combustion processes [4], as well as nuclear engineering [5]. The RTE is an ...Radiative transfer theory provides the theoretical framework for understanding light propagation in the ocean, just as hydrodynamics provides the framework for physical oceanography. The article begins with an overview of the deRnitions and terminology of radiative transfer as used in oceano-graphy. Various ways of quantifying the opticalRadiative Transfer Equation for Vegetation Canopies Solar radiation scattered from a vegetation canopy and measured by satellite sensors results from interaction of photons traversing through the foliage medium, bounded at the bottom by a radiatively participating surface. Therefore to estimate the canopy radiation regime, threeA radiative transfer simulation is often performed with the aim of comparing its results with observations. In that case, using a band wavelength grid produces directly comparable output. The alternative is to run the simulation using a regular wavelength grid with fairly narrow bins, and perform the convolution after the fact. ...Radiative heat transfer is the transfer of energy via thermal radiation, i.e., electromagnetic waves. It occurs across vacuum or any transparent medium (solid or fluid or gas). Thermal radiation is emitted by all objects …Radiation is responsible for most of the heat transferred into the room. Heat transfer also occurs through conduction into the room, but much slower. Heat transfer by convection also occurs through cold air entering the room around windows and hot air leaving the room by rising up the chimney. Exercise 1.7.1.Three one-dimensional radiative-transfer canopy models were compared to the BRF measurements in the near-infrared. The models generally fit the data for a young wheat canopy well. However, young corn and soybean canopies showed significant differences that are attributed to the escape of multiply scattered radiation from the sides of the canopy.When modeling radiative heat transfer, we need to think about how radiation is emitted from a surface and absorbed by other surfaces, as well as how much radiation is exchanged between surfaces. We've addressed emission, reflection, and transmission in two previous blog posts in this series, and now we will finish learning the foundations of ...The fast 3D radiative transfer package called Simulated Weather Imagery has been developed to serve the development and application needs of high-resolution atmospheric modeling. Visually and physically realistic, full natural-color (e.g., Miller et al., 2012) SWIm imagery offers, for example, a holistic display of numerical model output ...The three ways that heat can be transferred are conduction, convection and radiation. Conduction is most efficient in solids, convection occurs in liquids and gases and radiation occurs through anything that allows radiation to pass through...Topics. Review of Basic Thermal Radiation Concepts, Blackbody Radiation. Near Field Thermal Radiation, Fluctuation-dissipation Theory. This section lists the various topics …The Limb Radiation Retrival Transfer group (LRRT) is based on the Institute of Umweltphysik (IUP), at the University of Bremen, Germany. The group is led by Dr."Radiative Transfer is the definitive work in the field. It provides workers and students in physics, nuclear physics, astrophysics, and atmospheric studies with the foundation for the analysis of stellar atmospheres, planetary illumination, and sky radiation.The radiative transfer equation for synchrotron and bremsstrahlung are then solved by tracing these null rays from the observer to the emitter, ignoring effects due to Comptonization. For solving the transfer equation including Compton/inverse-Compton scattering, a Monte Carlo method is used, and here the photons are traced from the emitter to ...of radiative transfer in a nutshell. Literature: The book by Rybicki & Lightman "Radiation processes in Astrophysics", which emphasizes the various physical processes that produce, absorb and scatter radiation, but also has a bit of fundamental theory of radiative transfer in it. Lecture notes by Rob Rutten "Radiative transfer in stellar ...Radiative Transfer. " Radiative Transfer is the definitive work in the field. It provides workers and students in physics, nuclear physics, astrophysics, and atmospheric studies with the foundation for the analysis of stellar atmospheres, planetary illumination, and sky radiation. Though radiative transfer has been investigated chiefly as a ... Stefan–Boltzmann Law. Radiation heat transfer rate, q [W/m 2], from a body (e.g. a black body) to its surroundings is proportional to the fourth power of the absolute temperature and can be expressed by the following equation:. q = εσT 4. where σ is a fundamental physical constant called the Stefan–Boltzmann constant, which is equal to …Radiative transfer equations (RTEs) are obtained and analyzed in the framework of the homogeneous phase approach (HPA) and the multiphase approach (MPA). Analytical expressions are obtained for the absorption, extinction, and scattering coefficients, the scattering phase function, and the radiative thermal conductivity for very oblate particles ...For thermal radiation, where the typical dimension is provided by Wien's wavelength, Planck's law and associated concepts describing surface-to-surface radiative transfer have to be replaced by a full electromagnetic framework capturing near-field radiative heat transfer (photon tunnelling between close bodies), interference effects and sub ...DART (Discrete anisotropic radiative transfer) is a 3D radiative transfer model, designed for scientific research, in particular remote sensing. Developed at CESBIO since 1992, DART model was patented in 2003. It is freeware for scientific activities. General Description.Radiative Forcings. Atmospheric radiative transfer is the science of understanding how electromagnetic radiation emitted by both the Sun and Earth interacts with the gases, clouds and particles making up our atmosphere. The changes in energy due to these interactions are responsible for many variations in temperature and weather that we ...Feb 1, 2022 · Abstract. Using our decades-long experience in radiative transfer (RT) code development for Earth science, we endeavor to reduce the knowledge gap of bringing RT from theory to code quickly. Despite numerous classic and recent literature, it is still hard to develop an RT code from scratch within a few weeks. The research frontiers of radiative transfer (RT) in coupled atmosphere-ocean systems are explored to enable new science and specifically to support the upcoming Plankton, Aerosol, Cloud ocean Ecosystem (PACE) satellite mission. Given (i) the multitude of atmospheric and oceanic constituents at any given moment that each exhibits a large variety of physical and chemical properties and (ii) the ...An overview of the publicly available radiative transfer Spherical Harmonics code (SHARM) is presented. SHARM is a rigorous code, as accurate as the Discrete Ordinate Radiative Transfer (DISORT) code, yet faster. It performs simultaneous calculations for different solar zenith angles, view zenith angles, and view azimuths and allows the user to make multiwavelength calculations in one run. The ...DISORT (DIScrete Ordinate Radiative Transfer) solves the problem of 1D scalar radiative transfer in a single optical medium, such as a planetary atmosphere. The code correctly accounts for multiple scattering by an isotropic or plane-parallel beam source, internal Planck sources, and reflection from a lower boundary. Provided that polarization effects can be neglected, DISORT efficiently ...Back in the old days, transferring money to friends and family was accomplished by writing checks. This ancient form of payment was often made even more arduous by the necessity of sending the check via snail mail.The radiative transfer equation was solved in all cases using the MURaM solver (Vögler et al., 2005). To this end we implemented a diagnostic radiative transfer that computes the intensity along twelve different outgoing ray-directions plus the vertical one.3. Radiation Heat Transfer Between Planar Surfaces. Figure 19.5: Path of a photon between two gray surfaces. Consider the two infinite gray surfaces shown in Figure 19.5. We suppose that the surfaces are thick enough so that (no radiation transmitted so ). Consider a photon emitted from Surface 1 (remembering that the reflectance ):Abstract. This paper gives an update of the RTTOV (Radiative Transfer for TOVS) fast radiative transfer model, which is widely used in the satellite retrieval and data assimilation communities. RTTOV is a fast radiative transfer model for simulating top-of-atmosphere radiances from passive visible, infrared and microwave downward-viewing satellite radiometers. In addition to the forward model ...Radiative transfer (RT) theory is the physical approach to describe these paths and processes quantitatively. In water, propagation of electromagnetic radiation is heavily hampered by absorption. Fig. 2.1 shows the absorption coefficient of pure water ( Hale and Querry, 1973 , Segelstein, 1981 ) and the related penetration depth specifying the ...Radiative transfer is the theory describing how electromagnetic radiation is created, transmitted, absorbed, and scattered in a medium such as a planetary atmosphere, stellar photosphere, or interstellar medium. The medium can emit, absorb, and scatter radiation with a behavior that could vary strongly with wavelength according to the different ...which states the obvious fact that in the absence of internal sources, the upward radiation (and ultimately the radiation field at any optical depth ) is completely determined by the intensity of inward radiation. Indeed, taking into account that. is well known in the radiative transfer theory ( Sobolev 1963 ).The understanding of Earth's climate depends to a large extent on our knowledge of radiative transfer processes in the atmosphere. Short wavelength radiation in the visible range from the sun enters the atmosphere and finds its way to the surface to warm it. Long wavelength radiation in the infrared range is emitted from the surface to find its way to … Read moreDISORT is a discrete ordinate algorithm for monochromatic unpolarized radiative transfer in non-isothermal, vertically inhomogeneous, but horizontally homogeneous media. It can treat thermal emission, absorption, and scattering with an arbitrary phase function covering the electromagnetic spectrum from the ultraviolet to radio.Yet, in all environmental prediction models and in most satellite remote sensing techniques, radiative transfer is computed assuming clouds and their radiative boundary conditions to be plane‐parallel (i.e., horizontally homogeneous out to infinity), hence simplified to 1-D (the vertical) radiative transfer. This makes radiative transfer ...Radiative transfer (RT) simulation based on reconstructed 3-dimensional (3D) vegetation scenarios can promote the validation and development of various retrieval algorithms to monitor the growing ...7 Radiative Transfer. Radiation through empty space is what makes astronomy possible, but it isn’t so interesting to study on its own. Radiative transfer, the effect on radiation of …diative transfer (RT) theory provides a heuristic approach that does this task in an efficient way. RT theory is based on the law of conservation of energy and makes use of the single scattering properties of scatterers in the medium. The radiative transfer theory was develped by Schuster in the study of light propagation in foggy atmosphere [3].The radiative transfer equations are well known, but radiation parametrizations in atmospheric models are computationally expensive. A promising tool for accelerating parametrizations is the use of machine learning techniques. In this study, we develop a ...This paper focuses on the canopy radiation transfer scheme. As subscheme of a land surface model its main purpose is to calculate the amounts of radiative energy absorbed by the vegetation and the soil surface. The required input parameters are the optical properties of the leaves and the soil, the leaf area index (LAI), and a parameter that ...This course investigates the principles of thermal radiation and their applications to engineering heat and photon transfer problems. Topics include quantum and classical models of radiative properties of materials, electromagnetic wave theory for thermal radiation, radiative transfer in absorbing, emitting, and ….The total change of radiation The sum of (2) and (4) gives the combined effect, which gives a differential equation describing radiative transfer in the absence of scattering dIl ds = rkl (Bl (T) - Il). (5) Integrating the radiative transfer equation Multiplying (5) by the integrating factor exp É , gives s 0 rkl ds' dIl ds exp É s 0 rkl ds ...SIMPLE RADIATION TRANSFER FOR SPHERICAL STARS Under LTE (Local Thermodynamic Equilibrium) condition radiation has a Planck (black body) distribution. Radiation energy density is given as Ur,νdν = 8πh c3 ν3dν ehν/kT −1, (LTE), (tr.1) and the intensity of radiation (measured in ergs per unit area per second per unit solid angle, i.e. per ...1. Introduction. Energy transport due to radiation plays an important role in many scientific applications. For this reason, scientific communities such as in radiative transfer [1], [2], [3], neutron transfer [4], optical imaging [5], biomedical optics [6], astrophysics [7], etc., are actively involved in modelling radiation and its propagation.To …Radiative transfer (RT) codes are scientific software that numerically simulate the propagation of electromagnetic radiation through a medium. RT simulations are used in various disciplines including astrophysics, planetary and Earth science, and remote sensing. RT codes are a fundamental componentAn Introduction to Radiative Transfer presents these techniques as applied to stellar atmospheres, planetary nebulae, supernovae, and other objects with similar geometrical and physical conditions. Accurate methods, fast methods, probabilistic methods and approximate methods are all explained, including the latest and most advanced techniques.1999. RAMI 1. This is the official site of the RAdiation transfer Model Intercomparison ( RAMI) initiative. RAMI proposes a mechanism to benchmark models designed to simulate the transfer of radiation at or near the Earth's terrestrial surface, i.e., in plant canopies and over soil surfaces. As an open-access, on-going activity, RAMI operates ... Radiative Transfer in Planetary/Cometary Atmospheres and Light Scattering by Small Dust Particles. Experimental and Theoretical Study of the Scattering Behavior of Dust Particles., scattering, polarization, dust, atmospheres, comets, experiments Laurent Pilon, University of California Los Angeles, Department of Mechanical and Aerospace ...Radiative transfer (RT) codes are scientific software that numerically simulate the propagation of electromagnetic radiation through a medium. RT simulations are used in various disciplines including astrophysics, planetary and Earth science, and remote sensing. RT codes are a fundamental componentThe third edition of Radiative Heat Transfer describes the basic physics of radiation heat transfer. The book provides models, methodologies, and calculations essential in …RA D1ATION AND RADIATIVE TRANSFER 313 65. The Radiative Energy Flux and Momentum Dens, Jan 7, 2022 · Radiative transfer equations are often written in terms o, The radiative transfer equation is an integro-differential , DISORT (DIScrete Ordinate Radiative Transfer) solves the problem of 1D scalar radiative transfer in a single op, Keywords: radiative transfer, atmosphere, ocean surface, ocean body, PACE Frontiers in Earth S, Based on this radiative transfer equation, radiation intensity observed by sat, Radiative transfer is the transport of energy by electromagnetic waves through a gas. This example , Abstract. In many important combustion applications, heat transf, Aug 25, 2021 · A Deep Learning Approach to Fast Radiative Tran, When the radiative transfer reaches the equilibriu, The governing equation for the radiation processes is the radiat, Direct ordinate tangent linear radiative transfer (DOT, To associate your repository with the radiative-transfer topic, visit, MODTRAN solves the radiative transfer equation including the eff, The radiative transfer equation is solved by means of the d, Community Radiative Transfer Model (CRTM, [6]) and Radiative Transfe, We all take photos with our phones, but what happe, To begin with we introduce the basic concepts and techniques of.