Abstract: A method and system for a multi-spectrum celestial navigation system includes a first sensor responsive to at least a first and a second wavelength band of electromagnetic radiation. The sensor is configured to generate a first output related to the first wavelength band of electromagnetic radiation and to generate a second output related to the second wavelength band of electromagnetic radiation. The system also includes a processor programmed to receive the first and second outputs, determine a position of the sensor with respect to one or more stars using a stored star catalog and the received first and second outputs, and output the determined position.

Abstract: The present system and method detects and predicts potential tornadic activity. In one aspect, the invention predicts potential tornadic activity based on radar data. In another aspect, the invention predicts potential tornadic activity based on an integrated and composite product based on model forecast data and radar data by generating a composite tornado potential index using weighted values of the model forecast data and the radar data.

Abstract: A method of predicting and communicating transient hygrothermal behavior of an installed building component in a building wherein an interior environment of the building is materially affected by an environment exterior of the building, includes: defining a performance characteristic of the building component that is affected by transient hygrothermal behavior of the building component; defining exterior and interior climatic factors that affect the defined performance characteristic wherein the interior climatic factors are a function of the exterior climatic factors; and defining one or more non-climatic factors that affect the defined performance characteristic. Inputting these factors into a transient hygrothermal simulation software program to create a software model for performing simulations which predict changes in the defined performance characteristic, as a function of time, that are compared with a threshold performance characteristic value, to provide a user guide.

Abstract: Systems and methods are provided for determining data center cooling and power requirements and for monitoring performance of cooling and power systems in data centers. At least one aspect provides a system and method that enables a data center operator to determine available power and cooling at specific areas and enclosures in a data center to assist in locating new equipment in the data center.

Abstract: Apparatus and method are provided for facilitating simulation of heated airflow exhaust of an electronics subsystem, electronics rack or row of electronics racks. The apparatus includes a thermal simulator, which includes an air-moving device and a fluid-to-air heat exchanger. The air-moving device establishes airflow from an air inlet to air outlet side of the thermal simulator tailored to correlate to heated airflow exhaust of the electronics subsystem, rack or row of racks being simulated. The fluid-to-air heat exchanger heats airflow through the thermal simulator, with temperature of airflow exhausting from the simulator being tailored to correlate to temperature of the heated airflow exhaust of the electronics subsystem, rack or row of racks being simulated. The apparatus further includes a fluid distribution apparatus, which includes a fluid distribution unit disposed separate from the fluid simulator and providing hot fluid to the fluid-to-air heat exchanger of the thermal simulator.

Abstract: A method for optimizing sound and vibration comfort in a mobile passenger compartment, the method applied by a design team to carry out overall design of the passenger compartment and/or by at least one equipment supplier to carry out design of a portion of the passenger compartment. The method establishes target values to be achieved for well-identified comfort indices, defines requirements and input data relating to plural equipment suppliers to obtain a totality of information relating to the passenger compartment, estimates values of the comfort indices and compares them with the target values, and then modifies individually or in combination the input data to correlate them with the target values.

Abstract: A computer system to predict a value of a signal from a sensor schedule loads across a set of processor cores is described. During operation, the computer system generates N models to predict the value of the signal based on a set of quantized telemetry signals, where a given model produces a value of the signal using a subset of the set of quantized telemetry signals, and where the subset is selected from the set of quantized telemetry signals based on an objective criterion. Next, the computer system predicts the value of the signal by aggregating the values produced by the N models.

Abstract: A geophysical model of a subsurface region is generated based on seismic data, e.g., seismic reflection data. Migration and seismic inversion are applied to the seismic data to generate estimates of one or more physical or seismic properties of the subsurface region. Seismic inversion, such as spectral shaping inversion, is applied before or after migrating the seismic data through a variety of techniques that each avoid the amplification of dipping energy while optimizing computational efficiency and/or accuracy.

Abstract: The present invention provides a method to construct stable, high-order explicit discretization for the wave equation based on the discretization of the evolution formula. The present invention provides independent computation of discretization in one, two, or more spaces for bulk propagation, near boundaries propagation, and discretization of a projection operator to enforce boundary conditions. More specifically, the method includes an act of discretizing propagation operators L?t by using an identity that is derived using central differencing in time. The method also includes an act of providing a high-order discretization of a boundary projection operator that enforces boundary conditions independent of the discretization of the propagation operators L?t.

Abstract: A tool for simulating an industrial control system is provided. The tool includes a simulation component to emulate one or more simulation models according to a simulated execution environment. A switch component is associated with the simulation component to selectively enable or disable variability in the simulation models.

Abstract: Automatic detection and accurate time picking of weak events embedded in strong noise such as microseismicity induced by hydraulic fracturing is accomplished by: a noise reduction step to separate out the noise and estimate its spectrum; an events detection and confidence indicator step, in which a new statistical test is applied to detect which time windows contain coherent arrivals across components and sensors in the multicomponent array and to indicate the confidence in this detection; and a time-picking step to accurately estimate the time of onset of the arrivals detected above and measure the time delay across the array using a hybrid beamforming method incorporating the use of higher order statistics. In the context of hydraulic fracturing, this could enhance the coverage and mapping of the fractures while also enabling monitoring from the treatment well itself where there is usually much higher and spatially correlated noise.

Abstract: A computer-implemented method for generating depth-of-field effects includes receiving information specifying an input image rendered using a pinhole camera. A first set of circles of confusion associated with portions of the input image are determined based a set of parameters associated with the pinhole camera. The first set of circles of confusion are then associated with heat conductivity of a medium. The portions of the input image are blurred according to heat diffusion in the medium to generate a first output image having a first depth-of-field effect.

Abstract: Systems for simulating vehicle operation include a computer having a pedal activation program, the pedal activation program comprising instructions for generating signals relating to operation of a vehicle from the computer to a pedal sensor output according to a predetermined driving profile. Methods for simulating vehicle operation include providing a computer having a pedal activation program, utilizing the pedal activation program to initiate output signals to a pedal sensor output relating to a vehicle condition and transmitting the output signals to an engine control unit to implement a driving profile programmable within the pedal activation program.

Abstract: A system for modeling chemical reactions using analog or hybrid-analog-digital electronic circuits. The system exploits similarities between the kinetic rates of chemical reaction and the rates governing current flow in electronic devices such as bipolar junction transistors (BJTs) and metal oxide semiconductor field effect transistors (MOSFETs) operating at subthreshold conditions. These devices, which accurately model the stochastics of chemical processes, can networked into large array to model chemical reaction networks, including biochemical reactions and genetic processes such as activation, induction, transcription, and translation.

Abstract: This invention relates generally to a method of simulating the signal of an electromagnetic source using one or more dipole sources. In the method a dipole source is located at an excitation location corresponding to a segment of the electromagnetic source to be simulated. The dipole source is activated, and an electromagnetic signal recorded at one or more receiver locations. This process is repeated for additional excitation locations corresponding to additional segments of the electromagnetic source. The data from the sequence of dipole source excitation locations is processed to determine the simulated signal of the electromagnetic source.

Abstract: A multicomponent induction logging tool is used on a MWD bottomhole assembly. Multifrequency focusing that accounts for the finite, nonzero, conductivity of the mandrel is applied. Using separation of modes, the principal components and relative dip angles in an earth formation are determined. The results are used for reservoir navigation in an earth formation.

Abstract: The present invention is a system and method for generating predictions for various parameters in a reservoir. The invention includes receiving input data characterizing the reservoir and determining transient areas. The transient areas are determined by receiving data from the reservoir, transforming the data using discrete wavelet transformation to produce transformed data, removing outliers from the transformed data, identifying and reducing noise from in the transformed data and then detecting transient areas in the transformed data. A computer model is produced in response to the transient data and predictions for parameters in the reservoir are determined. These predictions are verified by comparing predictive values with a reservoir model and then the predictions for the various parameters can be used.

Abstract: A combined statistical-deterministic approach to methods and systems for assessing risk associated with natural disasters, in particular, hurricane wind risk. One example of a method of predicting wind speed distribution within a predetermined distance from a point of interest includes steps of statistically synthesizing a large plurality of wind storm tracks that pass within a predetermined radius of the point of interest, running a deterministic simulation of wind intensity along each one of the large plurality of wind storm tracks to produce an output representative of wind speed distribution along each track, and using the output to estimate an overall wind speed probability distribution from a combination of the wind speed distributions along each track within the predetermined distance from the point of interest.

Abstract: The present invention incorporates the use of model-driven and data-driven methodologies to attenuate multiples in seismic data utilizing a prediction model which includes multiply-reflected, surface-related seismic waves. The present invention includes beam techniques and convolving a predicted multiples beam with a segment of a modeled pegleg beam to obtain a convolved multiples beam. The convolved multiples beam can then he deconvolved to attenuate the multiples that are present in the original input beam.

Abstract: Described is a finite-difference methodology for efficiently computing the response from a model subject to changes within sub-volumes with the sub-volume enclosed with an extrapolation surface within an injection boundary using Green's functions to update the injection boundary and transmitting an updated wavefield from the injection boundary back into the altered sub-volume to include higher order reflections from outside of the altered sub-space.

Abstract: Systems and methods are provided for visually realistic simulation and real-time rendering of natural atmospheric lighting and related phenomena in an outdoor scene represented by an image provided by a simulation environment. The systems and methods of the present invention provide techniques to approximate the visual effects of natural atmospheric lighting and related phenomena that are visually realistic and that can be computed in real-time to render frames of a scene at real-time frame rates per second. The techniques consider the light scattering effects due to sunlight and ambient light in relation to objects, atmospheric particles and other scene elements represented by the image.

Abstract: Techniques for enhancing thermal design of a system having a number of boundary values are provided. A method for such enhancement includes representing thermal response of the system to the boundary values, obtaining at least one constraining parameter, and determining spatial and/or temporal distribution of the boundary values. The thermal response is represented as a superposition of temperature fields associated with given boundary values. The spatial and/or temporal distribution of the boundary values is determined based on the thermal response represented in the representing step, so as to satisfy the constraining parameter. The boundary values can be, for example, power sources, and the at least one constraining parameter can be, for example, a spatial or temporal location of one of the power sources.

Abstract: A method of modeling an integrated circuit includes: specifying a layout for the integrated circuit, wherein the layout includes a plurality of devices arranged in a plurality of layers and a plurality of connections between the layers; specifying locations for a source point and an observation point for the integrated circuit; determining a plurality of static images for the source point and the observation point; determining a plurality of discrete complex images for the source point and the observation point; determining a Green's-function value for the source point and the observation point by combining the static images and the discrete complex images; and saving at least some values based on the Green's-function value.

Abstract: A method is provided for assessing whether to terminate a computer-implemented simulation of a physical experiment. Computations associated with the computer-implemented simulation that model the physical experiment are executed and to determine if a desired outcome associated with the physical experiment will occur. The results of the computations are evaluated to determine if the results indicate that the desired outcome has occurred. If the desired outcome has not occurred, periodically the results of the computations are evaluated with respect to at least one negative indication that the desired outcome is not possible and thus not likely going to occur. If the at least one negative indication is present, the computations associated with the computer-implemented simulation is terminated.

Abstract: A method for solving a matrix equation AX=B, wherein A represents a block sparse matrix, B represents a right hand side block vector and X represents a solution block vector. In one embodiment, the method includes receiving the block sparse matrix and the right hand side block vector, constructing a reduced transformed block sparse matrix from the block sparse matrix, constructing a reduced transformed residual block vector from the block sparse matrix and the right hand side block vector, and solving for the solution block vector using the reduced transformed block sparse matrix and the reduced transformed residual block vector.

Abstract: A computer-implemented inversion method for determining characteristics of a bottom roughness field using a numerical wave model is provided. Measured wave heights over an area of interest are compared to predicted wave heights calculated by a wave model using an estimated bottom roughness parameter. If the error between the measured wave heights and the predicted wave heights is within a specified tolerance level, the analysis ends and the value of the bottom roughness parameter used in the wave model is retrieved. If the error is not within the specified tolerance level, an Influence Matrix IM is used to obtain a revised estimated bottom roughness parameter. The wave model is re-run using the revised roughness parameter and the resulting predicted wave heights are compared to the measured wave heights. The inversion continues until the wave height error is within the specified tolerance level. When the inversion ends, the bottom roughness field that produced those predicted wave heights is retrieved.

Abstract: A method for verifying an inertial unit for a moving body, the unit being mounted on a movement simulator, and the method includes: theoretical modeling of the inertial unit on the movement simulator, supplying theoretical inertial data representing measurement inertial data deemed to be measured by the inertial unit; simulation modeling including modeling of the inertial unit in a real navigation environment, the simulation modeling being fed with control commands and supplying simulation inertial data representing output data from the inertial unit in real navigation environment; calculating control commands as a function of the measurement inertial data, the simulation inertial data, and the theoretical inertial data; and validating the inertial unit by comparing the path of the moving body with a reference path.

Abstract: A system and method for predicting fatigue life in metal alloys for very high cycle fatigue applications. The system and method are especially useful for cast metal alloys, such as cast aluminum alloys, where a fatigue endurance limit is either non-existent or hard to discern. Fatigue properties, such as fatigue strength in the very high cycle fatigue region, are based on a modified random fatigue limit model, where the very high cycle fatigue strength and infinite life fatigue strength are refined to take into consideration the sizes of the discontinuities and microstructure constituents since the fatigue life scatter depends upon the presence of discontinuities and microstructure constituents. The sizes of the discontinuities and microstructure constituents that can initiate fatigue cracks can be determined with extreme value statistics, then input to the modified random fatigue limit model.

Abstract: A system and method is provided for an asymmetric formulation whereby multiple water masses mix together and generate an ‘eddy-like’ feature. Given the core and the shore profiles, embodiments produce a three-dimensional eddy representation for a particular ocean region based on three (core, inshore and offshore) specified profiles. The formulation employs parameter-based feature models and is generalized to ocean regions having asymmetric eddy water masses. Embodiments apply to regions in the global coastal ocean, providing nowcasting and forecasting in any oceanic region where eddies are part of the overall circulation. Examples of such eddies are off of Cape São Tomé (CST) and Cape Frio (CF) along the southeastern coast of Brazil.

Abstract: A system and method of predicting multi-dimensional meteorological and acoustic effects within and above a forest environment comprises collecting input data comprising meteorological and forest canopy characterization data for a specified forest environment; inputting the input data into program meteorology modules comprising an embedded radiative transfer and energy budget methodology module adapted to predict a heat source within and above the forest environment for any location at any time; calculating an incoming total radiation at a top of the forest environment; outputting multi-dimensional acoustics and meteorology numerical codes based on the program meteorology modules and the calculated total radiation; and formulating sound speeds within and above the forest environment based on the numerical codes.

Abstract: A method and system for simulating defects in conduits, where the defects are detected using long-range guided-wave inspection techniques. The guided wave interaction with a defect is treated as a one-dimensional problem of plane wave reflection from a boundary of different acoustic impedances. The defect waveform is simulated using an electrical transmission line model and inverse fast Fourier transformation.

Abstract: An electrical load is supplied with power from a driving power source, and a microprocessor (CPU) controls the opening/closing current supply rate (duty factor) of an opening/closing element in accordance with target current and driving power source voltage so that open loop control is carried out to achieve predetermined target current. The voltage between both the ends of a current detecting resistor connected to the ground side of the opening/closing element is input as a monitoring voltage from a current detecting amplifying circuit portion through a multichannel AD converter to CPU. When the error between the comparison target voltage corresponding to the target current and the monitoring voltage is above a first permissible error, CPU judges that there is an abnormality sign, and if the error is above a larger second permissible error, CPU judges that there is appearing abnormality.

Abstract: Methods for computer-implemented simulation for the interaction of two or more objects are provided. Data describing particles that represent each of the objects is generated from geometric data for objects. The data for each particle describes a mass density, velocity and energy at a position of the corresponding object. The particles are grouped into sectors to define a computational mesh comprising a plurality of sectors, wherein each sector is a volume region at a position in space in which particles associated with the objects may reside. For each of a plurality of select particles, so called neighboring particles are determined that are within a region of influence with respect to a select particle. Computations are performed based on laws of conservation of mass, energy and momentum to produce updated values for mass, velocity, energy, pressure, stress and position for the particles at each of a plurality of time steps.

Abstract: A computationally efficient general method of modeling or simulating matrix acidizing treatment when flow is not axisymmetric involves determining streamlines in the general flow field using complex potential theory to solve for the flow along the streamlines. The flow over a time step is used to model the propagation of the acid front and the creation and extension of wormholes.

Abstract: To perform inversion based on electromagnetic (EM) data acquired in a subterranean survey, time domain controlled source EM (TD-CSEM) data is acquired by at least one EM receiver in response to EM signals from a controlled EM source. Further data is received, where the further data is selected from among magnetotelluric (MT) data and DC data acquired by the at least one receiver. A probabilistic joint inversion is applied on the TD-CSEM data and the further data to produce a model representing a subterranean structure that is a target of the subterranean survey.

Abstract: A method and apparatus for constructing a velocity model of a subsurface of the earth, is disclosed herein. Seismic data may be received. A first velocity model of the subsurface may be constructed using the seismic data. The subsurface may have one or more salt bodies. A second velocity model of the subsurface without the salt bodies may be constructed using the seismic data. A set of attributes induced by the salt bodies may be determined based on the first velocity model and the second velocity model. A stiffness tensor change between the first velocity model and the second velocity model may be calculated based on the set of attributes induced by the salt bodies. The first velocity model may be updated based on the stiffness tensor change.

Abstract: A method is disclosed for executing a physics simulation in a system comprising a computational platform, a main application stored in the computational platform, a secondary application stored in the computational platform, and a smoothed particle hydrodynamics (SPH) application programming interface (API) implemented in the computational platform. The method defines a SPH call in the SPH API, and by operation of the main application, invokes a software routine using the SPH call. Additionally, by operation of the secondary application, a state of the physics simulation is updated in response to the software routine.

Abstract: A layered heater structure including an electrode layer and a localized tuning method for tuning the electrode layer of a layered heater structure with high precision is provided. The localized tuning method tunes the electrode layer to its proper local resistance to minimize temperature offsets on the heater surface and thus provide a desired thermal profile that is in marked contrast to conventional, non-localized resistance tuning approaches based on thickness trimming practices, such as grinding or blasting, or resistivity adjustment, such as local heat treatment.

Abstract: Apparatus and method are provided for facilitating simulation of heated airflow exhaust of an electronics subsystem, electronics rack or row of electronics racks. The apparatus includes a thermal simulator, which includes an air-moving device and a fluid-to-air heat exchanger. The air-moving device establishes airflow from an air inlet to air outlet side of the thermal simulator tailored to correlate to heated airflow exhaust of the electronics subsystem, rack or row of racks being simulated. The fluid-to-air heat exchanger heats airflow through the thermal simulator, with temperature of airflow exhausting from the simulator being tailored to correlate to temperature of the heated airflow exhaust of the electronics subsystem, rack or row of racks being simulated. The apparatus further includes a fluid distribution apparatus, which includes a fluid distribution unit disposed separate from the fluid simulator and providing hot fluid to the fluid-to-air heat exchanger of the thermal simulator.

Abstract: A system and device for estimating an amount of time needed for a vehicle brake assembly to cool to a predetermined temperature includes a first input for receiving data indicative of a temperature of the brake assembly, a second input for receiving data indicative of at least one environmental condition that affects cooling of said brake assembly, a processor and memory, and logic stored in said memory and executable by said processor. The logic stored in memory includes logic that simulates a temperature response of the brake assembly based on the brake assembly temperature and the at least one environmental condition.

Abstract: A method and system is disclosed for determining the internal structure and constituent properties of complexly structured materials using a computational simulation engine to calculate field propagation properties, physical testing of the materials to obtain measured field properties, and correlation of the calculated and measured field properties. The complexly structured materials consist of particles, inclusions, or voids of arbitrary distributions and compositions suspended in a matrix. The particles or inclusions can additionally display substructure such as layers or embedded subparticles, sub-inclusions, or voids. The simulation engine calculates multiple scattering in simulated materials using a multipole expansion method, and is used to generate a look-up table of propagation properties for a range of probable structures and compositions. The measurements are then classified with respect to the look-up table.

Abstract: A method and computer system for predicting or calculating the quality factor of a mechanical resonant (MR) device. The system and method simulates uncoupled elastic vibration of the MR device to produce simulated dilatation of the MR device, collects data relating to the dilatation and maximum stored elastic vibration energy of the device design. It determines the internal heat source data of the MR device caused by dilatation based on the thermal expansion effect of the MR device material, conveying the internal heat source data along with transient heat conduction data to a simulation engine, which simulates and determines the temperature variation within the MR device. Thermoelastic damping over one cycle of vibration of the MR device is determined, enabling the determination of the quality factor relating to thermoelastic damping as a function of the thermoelastic damping over one cycle of vibration of the MR device, and the maximum elastic vibration energy stored over one cycle of vibration.

Abstract: A selective laser sintering technique and system are provided for producing a heterogeneous product. The selective laser sintering technique and system is generally comprised of generating a computer model of the product and processing the model to obtain numerous cross-sectional representations of the model. The cross-sectional representations are manufactured layer by layer to create the product. Specifically, numerous different powders having a variety of properties are placed within nozzles positioned above a deposition bed using a hopper. Using the computer model as a guide, the different powders are placed at different positions on the deposition bed to form each layer of the device. The deposited powders are consolidated, micromachined, and milled using one or more lasers to create the product.

Abstract: A virtual ?T trip criterion is implemented in an electrical power distribution system to provide current-based tripping for a solid state power switching device. A first-order system model is implemented either by hardware or software to represent a rise in temperature of the electrical wire through which power is supplied. When the simulated temperature exceeds a threshold, the solid state power switching device may be tripped.

Abstract: The disclosed computer-implementable method allows for the fast creation of a multi-unit interval data signal suitable for simulation. The created signal represents the output of an otherwise ideal Discrete Time Filter (DTF) circuit, and the quick creation of the signal merely requires a designer to input the number of taps and their weights without the need of laying out or considering the circuitry of the DTF. A matrix is created based on a given data stream, and the number of taps and weights, which matrix is processed to create the multi-unit-interval data signal. Noise and jitter can be added to the created signal such that it now realistically reflects non-idealities common to actual systems. The signal can then be simulated using standard computer-based simulation techniques. For example, the transmission of the created signal can be simulated down a channel having a particular transfer function.

Abstract: A designing method for a display module is provided. First, set a predetermined chromaticity value. Second, readjust a respective area distribution among a red subpixel, a blue subpixel and a green subpixel in a pixel to produce a simulated chromaticity value close to the predetermined one. Next, compare the predetermined chromaticity value with the simulated one. Then, repeat the step of adjusting the respective area of the red subpixel, the green subpixel and the blue subpixel until a difference between the predetermined chromaticity value and the simulated one is in a predetermined deviation. By means of adjusting the area distribution among the different subpixels, the chromatic aberration of LCD could be improved.

Abstract: A diagnosis support system for cancer is disclosed that comprises: a measurement value acquiring section for acquiring a measurement value of a first cancer patient; a sample data memory for storing sample data of a plurality of cancer patients different from the first patient; a reference range determination section for determining a reference range based on the measurement value of the first cancer patient; a display unit; and a display controller for controlling the display unit to display a diagnosis support screen showing the clinical information included in the sample data having measurement value within the reference range. A method of providing cancer diagnosis support information and a computer program product are also disclosed.

Abstract: A system to simulate pyrotechnic shock may include a pulse or signal generator to generate a predetermined signal waveform. A signal conditioning device may be included to condition the predetermined signal waveform to produce a predetermined shock simulation for a shock test. The system may also include a power amplifier to amplify the conditioned predetermined signal waveform to a chosen amplitude to produce a selected level of shock. A shaker system produces the selected level of shock in response to an amplified signal waveform from the power amplifier. A shock measuring device measures a shock imparted to the test specimen, and an output device presents a result of the shock test on the test specimen.

Abstract: Systems for, and methods of, generating a visual representation of a wavelength division multiplexing (WDM) optical network and nodes thereof. In one embodiment, a system for generating a visual representation of multiple nodes of a WDM optical network includes: (1) a connectivity, pass-through and error identifier configured to identify connectivity and any pass-throughs and termination errors with respect to at least some nodes of the WDM optical network and (2) a connectivity, pass-through and error displayer coupled to the connectivity, pass-through and error identifier and configured to generate the visual representation that indicates the connectivity and the any pass-throughs and termination errors.

Abstract: A real-time algorithm for rendering an inhomogeneous scattering medium such as fog is described. An input media animation is represented as a sequence of density fields, each of which is decomposed into a weighted sum of a set of radial basis functions (RBFs) such as Gaussians. The algorithm computes airlight and surface reflectance of the inhomogeneous scattering medium. Several approximations are taken which lead to analytical solutions of quantities such as an optical depth integrations and single scattering integrations, and a reduced number of integrations that need to be calculated. The resultant algorithm is able to render inhomogeneous media including their shadowing and scattering effects in real time. The algorithm may be adopted for a variety of light sources including point lights and environmental lights.