ray will be nearly parallel, and the image coordinates to a 3D unit vector, NASA’s Jet Propulsion Laboratory. Further angle between the direct ray and the negation of the z component of the information is contained in a TSP (see reflected ray can be approximated as unit vector, and conversion of the mod- page 1). two times the glancing angle. Calcula- ified unit vector back to 2D image This software is available for commercial li- tions to locate the pixel a direct ray en- coordinates. censing. Please contact Daniel Broderick of ters are simple and involve for any can- This work was done by Arturo L. Rankin the California Institute of Technology at didate water pixel conversion of the 2D and Larry H. Matthies of Caltech for [email protected]. Refer to NPO-47092.

Nonlinear Combustion Instability Prediction Marshall Space Flight Center, Alabama The liquid rocket engine stability physical understanding of the combus- The program accommodates any combus- prediction software (LCI) predicts tion instability problem, which has re- tion-chamber shape. The program can run combustion stability of systems sulted in a computationally predictive on desktop computer systems, and is readily using LOX-LH2 propellants. Both algorithm that allows determination of upgradeable as new data become available. longitudinal and transverse mode sta- pressure oscillation frequencies and This program was written by Gary Flandro of bility characteristics are calculated. geometry, growth rates for component the , Space Institute, This software has the unique feature modes of oscillation, development of Calspan Center, for Marshall Space Flight Cen- of being able to predict system limit steepened wave structures, limit (maxi- ter. For further information, contact Sammy amplitude. mum) amplitude of oscillations, and Nabors, MSFC Commercialization Assistance New methods for predicting stability changes in mean operation chamber Lead, at sammy.a.nabors@.gov. Refer to have been created based on a detailed conditions. MFS-32549-1.

JMISR INteractive eXplorer NASA’s Jet Propulsion Laboratory, Pasadena, California MISR (Multi-angle Imaging Spec - then warping the images to minimize and their extent, and wind direction. troRadiometer) INteractive eXplorer the misregistration offsets. Plots of BRF Overposting of MODIS thermal anom- (MINX) is an interactive visualization (bidirectional reflectance factor) vs. aly data aids in the identification of program that allows a user to digitize camera angle for points clicked in an smoke plumes. The software has been smoke, dust, or volcanic plumes in image can be displayed. Users get rapid used to preserve graphical and textural MISR multiangle images, and automat- access to map views of MISR path and versions of the digitized data in a ically retrieve height and wind profiles orbit locations and overflight dates, Web-based database that currently con- associated with those plumes. This in- and past or future orbits can be identi- tains more than 7,000 smoke plumes novation can perform 9-camera anima- fied that pass over a specified location (http://www-misr2.jpl.nasa.gov/ tions of MISR level-1 radiance images at a specified time. Single-camera, EPA-Plumes/). to study the 3D relationships of clouds level-1 radiance data at 1,100- or 275- This work was done by David L. Nelson of and plumes. MINX also enables archiv- meter resolution can be quickly dis- Columbus Technologies and Services; David J. ing MISR aerosol properties played in color using a browse option. Diner, Charles K. Thompson, Jeffrey R. Hall, and Moderate Resolution Imaging This software determines the heights and Brian E. Rheingans of Caltech; Michael J. Spectroradiometer (MODIS) fire ra- and motion vectors of features above Garay of Raytheon; and Dominic Mazzoni of diative power along with the heights the terrain with greater precision and Google, Inc. for NASA’s Jet Propulsion Labora- and winds. It can correct geometric coverage than previous methods, based tory. For more information, download the misregistration between cameras by on an algorithm that takes wind direc- MINX software package and User’s Guide at correlating off-nadir camera scenes tion into consideration. Human inter- http://www.openchannelsoftware.com/ with corresponding nadir scenes and preters can precisely identify plumes projects/MINX/. NPO-47098

Characterization of Cloud Water-Content Distribution NASA’s Jet Propulsion Laboratory, Pasadena, California

The development of realistic cloud variables. To this end, a software tool was This software characterizes distribu- parameterizations for climate models re- developed to characterize cloud water- tions of cloud water content with re- quires accurate characterizations of sub- content distributions in climate-model spect to cloud phase, cloud type, precip- grid distributions of thermodynamic sub-grid scales. itation occurrence, and geo-location

38 NASA Tech Briefs, September 2010 using CloudSat radar measurements. It km and a variable vertical resolution be- estimating the probability density func- uses a statistical method called maxi- tween 100 m and 1 km. Since climate tion of cloud water content at the sub-grid mum likelihood estimation to estimate models cannot explicitly resolve what hap- scale using CloudSat measurements. the probability density function of the pens at the sub-grid scales, the physics This work was done by Seungwon Lee of Cal- cloud water content. must be parameterized as a function of tech for NASA’s Jet Propulsion Laboratory. For A crude treatment of sub-grid scale the resolved motions. The fundamental more information, contact iaoffice@jpl. cloud processes in current climate models problem of cloud parameterization is to nasa.gov. is widely recognized as a major limitation characterize the distributions of cloud This software is available for commercial li- in predictions of global climate change. variables at sub-grid scales and to relate censing. Please contact Daniel Broderick of the At present, typical climate models have a the sub-grid variations to the resolved California Institute of Technology at horizontal resolution on the order of 100 flow. This software solves the problem by [email protected]. Refer to NPO-47248.

Autonomous Planning and Replanning for Mine-Sweeping Unmanned Underwater Vehicles NASA’s Jet Propulsion Laboratory, Pasadena, California This software generates high-quality sumption of the vehicle when idle and tions of the vehicle and world states. The plans for carrying out mine-sweeping ac- when moving. effects of these updates are propagated tivities under resource constraints. The The planner begins by using a depth- into the future and allow the planner to autonomous planning and replanning first, branch-and-bound search algo- detect conflicts ahead of time, or to system for unmanned underwater vehi- rithm to find an optimal mine sweep to identify any resource surplus that might cles (UUVs) takes as input a set of prior- maximize the value of the mine-sweep exist and could allow the planner to in- itized mine-sweep regions, and a specifi- regions included in the plan, subjected clude additional mine-sweep regions. cation of available UUV resources to available resources. The software is- This work was done by Daniel M. Gaines including available battery energy, data sues task commands to an underlying of Caltech for NASA’s Jet Propulsion Labora- storage, and time available for accom- control architecture to carry out the ac- tory. For more information, contact plishing the mission. Mine-sweep areas tivities on the vehicle, and to receive up- [email protected]. vary in location, size of area to be swept, dates on the state of the world and the This software is available for commercial li- and importance of the region. The plan- vehicle. During plan execution, the censing. Please contact Daniel Broderick of ner also works with a model of the UUV, planner uses updates from the control the California Institute of Technology at as well as a model of the power con- system to make updates to the predic- [email protected]. Refer to NPO-47018.

Dayside Ionospheric Superfountain NASA’s Jet Propulsion Laboratory, Pasadena, California The Dayside Ionospheric Super - oped over many years at the Naval Re- sion Laboratory. For more information, fountain modified SAMI2 code predicts search Laboratory, and has importance contact [email protected]. the uplift, given storm-time electric relating to accuracy of GPS positioning, This software is available for commercial li- fields, of the dayside near-equatorial ion- and for satellite drag. censing. Please contact Daniel Broderick of osphere to heights of over 800 kilome- This work was done by Bruce T. Tsurutani, the California Institute of Technology at ters during magnetic storm intervals. Olga P. Verkhoglyadova, and Anthony J. [email protected]. Refer to NPO-47209. This software is a simple 2D code devel- Mannucci of Caltech for NASA’s Jet Propul -

In-Situ Pointing Correction and Rover Microlocalization NASA’s Jet Propulsion Laboratory, Pasadena, California Two software programs, marstie and sion-specific code in either of these pro- overlap, and presents overlapping pairs marsnav, work together to generate point- grams. This software corrects geometric to the user. The user then manually cre- ing corrections and rover micro-localiza- seams in images as much as possible ates a number of tiepoints between each tion for in-situ images. The programs are (some parallax seams are uncorrectable). pair, by identifying the locations of fea- based on the PIG (Planetary Image Geom- First, marstie is used to gather tie- tures that are common to both images. etry) library, which handles all mission de- points. The program analyzes the input An automatic correlator assists the user pendencies. As a result, there is no mis- image set, determines which images in getting subpixel accuracy on these tie-

NASA Tech Briefs, September 2010 39