Award Data

THIS PROPOSAL COVERS THE DEVELOPMENT OF A 0.25 WATT, 80 K MECHANICAL CRYOCOOLER FOR USE IN SENSOR COOLING IN SPACE. THE CRYOCOOLER WILL USE THE MIKULIN PULSE TUBE CYCLE THAT HAS NO MOVING PARTS IN THE COLD SECTION OF THE CRYOCOOLER. THE ELIMINATION OF COLD MOVING PARTS REMOVES THE MAIN SOURCES OF FAILURE AND OF VIBRATION IN THE CRYOCOOLER. LIFETIMES OF OVER FIVE YEARS SHOULD BE POSSIBLE WITH THIS ...

MOST TYPICAL PROBLEMS IN STRUCTURAL ENGINEERING ARE BEST ANALYZED BY APPROXIMATING AN OBJECT'S GEOMETRY WITH FINITE ELEMENTS. SELECTING AN APPROPRIATE MESHING STRATEGY FOR A GIVEN SOLID REQUIRES KNOWLEDGE ABOUT FINITE ELEMENT THEORY IN GENERAL, AND ABOUT PACKAGE-SPECIFIC DETAILS IN PARTICULAR. THE ADEPT SYSTEM INTEGRATES A TRADITIONAL SOLIDMODELER WITH AN EXPERT SYSTEM EQUIPPED WITH THIS KNOWLEDGE ...

THE OBJECTIVE OF THIS PROJECT IS TO DESIGN AND FABRICATE AN INNOVATIVE FINGERTIP-SHAPED TACTILE TELEPRESENCE SYSTEM FOR DEXTEROUS TELEROBOTIC SYSTEMS. THE PRINCIPAL TASKS TO BE PERFORMED ARE: (1) DESIGN OF VARIOUS MINIATURE TACTILE STIMULATOR ELEMENTS AND EVALUATION OF THE ACTUATION STRENGTH, DISPLACEMENT MAGNITUDE, FREQUENCY RESPONSE RANGE, AND THERMAL LOADING CHARACTERISTICS, (2) CONSTRUCTION OF ...

CIVILIAN AND MILITARY SPACECRAFT SYSTEMS, COMMUNICATIONS, DETECTION, TRACKING AND SURVEILLANCE ACTIVITES CAN BE ENDANGERED OR DEGRADED BY SOLAR ACTIVITY. THE SUN INDUCES THESE DISTURBANCES THROUGH MAGNETIC FIELD DISTURBANCES, ELECTROMAGNETIC AND CHARGED PARTICLE IRRADIATION OF THE EARTH'S UPPER ATMOSPHERES. ONE METHOD OF CIRCUMVENTING SERIOUS CONSEQUENCES OF THIS ACTIVITY IS THROUGH SPACE BASEDMON ...

FUNDAMENTAL PHYSICS OF THE COMBUSTION PROCESSES IN LIQUID ROCKET ENGINES IS VERY COMPLEX. RECENT ADVANCES IN COMPUTATIONAL FLUID DYNAMICS (CFD) PROVIDE A BASIC MECHANISM FOR DETAILED ANALYSES. THE EXISTENCE OF CFD TECHNIQUES INCREASES THE NEED OF ADEQUATE MODELS FOR PHYSICAL PROCESSES, SUCH AS: ATOMIZATION AND SPRAY FORMATIONUNDER SUB AND SUPERCRITICAL CONDITIONS, DROPLET-DROPLET INTERACTION, TURB ...

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THE OBJECTIVE OF THIS PROJECT WAS TO DEVELOP NUMERICAL METHODOLOGIES FOR ANALYZING SOLID-LIQUID PHASE CHANGE PROBLEMS INVOLVING MULTI-COMPONENT MATERIALS SUCH AS BINARY MIXTURES AND ALLOYS. THE POTENTIAL NASA INTEREST FOR THIS WORK STEMS FROM MATERIALS SCIENCE APPLICATIONS IN SPACE, E.G. CRYSTAL GROWTH. THE AIM OF PHASE I WAS TO DEFINE A FRAMEWORK FOR DEVELOPMENTOF A GENERAL PURPOSE COMPUTER PROGR ...

NASA IS CURRENTLY SUPPORTING A VERY PROMISING PROJECT FOR DEVELOPMENT OF A HIGH-POWERED MULTIPROCESSOR SYSTEM, THE NAVIER-STOKES COMPUTER (NSC). WHILE MULTILEVEL ALGORITHMS ARE BEING STUDIED IN THE NSC ENVIRONMENT FOR SOLVING THE ELLIPTIC EQUATIONS THAT ARISE IN DISCRETIZING INCOMPRESSIBLENAVIER-STOKES EQUATIONS, NO RESEARCH HAS YET FOCUSED ON LOCAL ADAPTIVE SCHEMES FOR THIS PURPOSE. THIS IS IMPOR ...

THE USE OF IMAGERY FOR THE PRESENTATION OF DATA IS BECOMING INCREASINGLY COMMON. INTEGRATING IMAGE DATA WITH GRAPHIC DATA STRUCTURES AND FEATURE INFORMATION IS VERY DIFFICULT USING TRADITIONAL DIGITAL REPRESENTATIONS. SEPARATE IMAGE AND FEATURE INFORMATION DATABASES ARE COMMONLY USED, BUT THE ANALYST IS REQUIRED TO MAINTAIN TWO OR MORE DATABASES AND TO PERFORM INTEGRATION OF THE INFORMATION IN HIS ...

IN THE GROWTH OF CRYSTALS FROM MELTING MATERIALS USING THE CZOCHRALSKI METHOD, A GOOD TECHNIQUE OF ACCURATELY CONTROLLING THE PROCESS DOES NOT EXIST. THERMOCOUPLES ARE LARGELY USED AT PRESENT, BUT THEY DO NOT PROVIDE ADEQUATE INFORMATION SUCH AS THE THERMAL GRADIENT ACROSS A SINGLE LARGE CRYSTAL. THE USE OF CHARGE-COUPLED DEVICES TO MEASUREAND CONTROL CRYSTAL GROWTH USING THE CZOCHRALSKI METHOD IS ...