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Freeing Space for NASA Freeing Space for NASA: Incorporating a Lossless Compression Algorithm into NASA’s FOSS System Kaitlyn Fiechtner, California State University, Fresno Allen Parker, NASA Dryden Flight Research Center Background Materials and Methods Conclusion Morse code… is an early example of data compression…” Stephen Gather data from FOSS system t1SFMJNJOBSZUFTUTJOEJDBUFUIBU-;0DPNQSFTTJPOBMHPSJUINT Wolfram, modern day scientists and inventor, explains in his book are compatible with data from the FOSS system. A New Kind of Science. Data compression has since progressed to t-;09 BOE-;0"TFFNUPCFUIFNPTUFòFDUJWFBMHPSJUINT digitized data, and in 1977 Abraham Lempel and Jacob Ziv created for the FOSS system a more e!cient compression algorithm—LZ compression. Instead of storing one static reference dictionary for the code (as in Morse code), LZ compression creates a code dictionary based on the data Looking Ahead being analyzed, so the coding correlates better with the data. In t/FFEUPJODPSQPSBUFCFUUFSUJNJOHGVODUJPOJOUPUIFQSPHSBNGPS 1996, Markus Oberhumer enhanced LZ compression by making an Compress Data better testing of compression speed algorithm, called LZO (Lempel Ziv Overhumer), that can be used t/FFEGVSUIFSBOBMZTJTPO-;0"DPNQSFTTJPOTQFFEUPEFUFSNJOF for real-time data compression. Oberhumer has since created JGJUJTDPOTJTUFOUMZNPSFGBTUFSUIBO-;09 many variations of the algorithm to enhance speed and/or t0ODFBO-;0BMHPSJUINJTJODPSQPSBUFEJOUPUIF'044TZTUFN UIF compression and decompression capabilities. extra data storage capacity created will allow the FOSS system to be in use for longer periods of time, making its application more Discussion Decompress Data practical for many structures, like long-#ight aircraft, wind turbines, NASA’s Fiber Optic Strain Sensing (FOSS) system, created to obtain bridges, and medical instruments used in lengthy testing. a better view of strain on an object by possessing more sensors, can gather and store up to 1,536,000 bytes per second (1.46 Acknowledgements megabytes per second). Since the FOSS system typically acquires t45"3TUBò /4' BOE/"4"GPSJNQMFNFOUJOHBOEGBDJMJUBUJOH hours—or even days—of data, the system can gather hundreds this internship. Results of gigabytes of data for a given test event. To free up memory t"MMFO1BSLFS 4ZTUFNT&OHJOFFS/"4"%'3$ GPSCFJOHBXPOEFSGVM space without compromising any data, NASA Dryden is incorporat- Preliminary results from oberhumer.com (using a slow processor) NFOUPS BOE1BUSJDL$IBO &MFDUSPOJDT&OHJOFFS/"4" GPSUIFFYUSB ing a Lempel-Ziv-Oberhumer (LZO) lossless data compression help and support algorithm to compress data as it is being acquired. The primary priority of the algorithm must be speed to keep up with data t3VTTFMM#JMMJOHT 7JDUPSJB$PTUB BOE:WPOOF$BNQPTGPSUIFBJE acquisition of the FOSS system. and support of the project and the future teaching applications Objectives References Wolfram, Stephen. (2002). A New Kind of Science. : Wolfram Media. t$POEVDUJOJUJBMUFTUTUPEFUFSNJOFJGUIF-;0BMHPSJUINJT Preliminary results from NASA Dryden tests compatible with the FOSS system Oberhumer, M. (1996). oberhumer.com. Retrieved June 8, 2011, from oberhumer.com (using a 64-bit processor) website: http://www.oberhumer.com/opensource/lzo/. t$POEVDUDPNQBSBUJWFUFTUTUPEFDJQIFSXIJDI-;0BMHPSJUIN Lempel, A, Ziv, J.(1977). A Universal Algorithm for Sequential Data Compression. is most e"ective for the FOSS system’s needs *&&&53"/4"$5*0/40/*/'03."5*0/5)&03: 5 t*ODPSQPSBUFUIFBMHPSJUINJOUPUIF'044TZTUFN -JN ) 'FCVSBSZ *OUFSBDUJWF%BUB$PNQSFTTJPO5VUPS Retrieved from http://www.eee.bham.ac.uk/WoolleySI/All7/ziv_1.htm 5IJTNBUFSJBMJTCBTFEVQPOXPSLTVQQPSUFECZUIF4%#FDIUFM +S'PVOEBUJPOBOECZUIF/BUJPOBM4DJFODF'PVOEBUJPOVOEFS(SBOU/PBOE(SBOU/P"OZPQJOJPOT öOEJOHT BOEDPODMVTJPOTPSSFDPNNFOEBUJPOTFYQSFTTFEJOUIJTNBUFSJBMBSFUIPTFPGUIFBVUIPSTBOEEPOPU OFDFTTBSJMZSFøFDUUIFWJFXTPGUIF4%#FDIUFM +S'PVOEBUJPOPSUIF/BUJPOBM4DJFODF'PVOEBUJPO'PSNPSFJOGPSNBUJPOLöFDIUO!HNBJMDPN.
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