Langley aerospace test highlights, 1985

The role of the Langley Research Center is to perform basic and applied research necessary for the advancement of aeronautics and space flight, to generate new and advanced concepts for the accomplishment of related national goals, and to provide research advice, technological support, and assistance to other NASA installations, other government agencies, and industry. Significant tests which were performed during calendar year 1985 in Langley test facilities, are highlighted. Both the broad range of the research and technology activities at the Langley Research Center and the contributions of this work toward maintaining United States leadership in aeronautics and space research, are illustrated. Other highlights of Langley research and technology for 1985 are described in Research and Technology-1985 Annual Report of the Langley Research Center

Fiscal year 1981 scientific and technical reports, articles, papers, and presentations

This bibliography lists approximately 503 formal NASA technical reports, papers published in technical journals, and presentations by MSFC personnel in FY-1981. It also includes papers of MSFC contractors. Citations announced in the NASA scientific and technical information system are noted

Safety and Mission Assurance Acronyms, Abbreviations, and Definitions

This NASA Technical Handbook compiles into a single volume safety, reliability, maintainability, and quality assurance and risk management terms defined and used in NASA safety and mission assurance directives and standards. The purpose of this handbook is to support effective communication within NASA and with its contractors. The definitions in this handbook are updated when the definition of the acronym or term is updated in the originating document

The role of mitochondrial genome in inherited optic neuropathies

Leber's hereditary optic neuropathy (LHON) and Dominant Optic Atrophy (DOA) are common cause of vision loss. LHON is due in 90% of cases to three common point mutations in mitochondrial genome (mtDNA), affecting complex I subunit genes. In 10% LHON is associated to a rare mtDNA mutation and, for the first time, with peculiar combinations of individually non-pathogenic missense mtDNA variants. The pathogenic potential of these mtDNA haplotypes is supported by multiple evidences: the LHON phenotype is strictly inherited along maternal line; the combinations of variants are unique; the mitochondrial defect is co-transferred into the cybrid-cell model; all but one of these variants clustered along the same predicted fourth E-channel deputed to proton translocation. Hence, the definition of the pathogenic role of a specific mtDNA mutation becomes blurrier than ever and, even in the absence of a clearly established LHON primary mutation, unprecedented combinations of missense mtDNA variants, individually known as polymorphisms, may lead to reduced OXPHOS efficiency sufficient to trigger LHON. In this complex scenario, mtDNA variability itself may play a modifying role in LHON and DOA. The mtDNA was completely sequenced in largest European cohort of 119 independent probands, carrying the m.14484T>C/MT-ND6 LHON mutation. Besides the occasional finding of double mutants and multiple founder events, we confirm the association with haplogroup J root, but not with its more recent sub-clades. The phylogenetic analysis suggests a possible double role of haplogroup J: predisposing factor to mutagenesis or preserving the mutation during evolution. On the clinical ground, the penetrance of m.14484T>C/MT-ND6 mutation increases on haplogroup J, especially in females. In DOA cohorts, the relationship with mtDNA genetic variation is complex: no specific haplogroups resulted associated with DOA, neither clearly modified its clinical outcome. We only documented a minor effect of mtDNA, and nDNA played a definitely stronger role as modifier

Design and Characterization of an Affordable Laser Communication System

Over the last decades, an exponential growth in communication demand has been observed. Radio Frequency (RF) band has been one of the most used bandwidths for data transmission in the world. Given the influence and the continuous growth of communication technology, the RF spectrum is overpopulated. More efficient systems are necessary to meet the communication needs of this generation. A change to optical bandwidth is the most practical alternative to deal with the congestion of radio frequency. The aim of this thesis is to present the features of Free Space Optical links with off-the-shelf components. A description of how these systems can apply to satellite communication is given. A theoretical background of the history of optical communications will be provided followed by a gander at the fundamental properties of FSO mechanisms. The thesis will conclude with a detailed description of the choice of hardware utilized, results, and future work

Quantum key distribution devices: How to make them and how to break them

As more aspects of modern society depend on digital communication, we increasingly rely on infrastructure that ensures the privacy and security of this communication. Classically, this has been provided by cryptographic protocols such as public-key encryption, in which secrets called keys are exchanged between different parties to enable secure communication. The rapid development of quantum algorithms which violate the assumptions of these protocols, however, poses a security challenge to modern cryptography. Quantum resources can also be used to strengthen cryptographic security, particularly the security of key exchange protocols. This approach, QKD, can be implemented by encoding in quantum systems such as single photons sent through free-space or a fiber. Fiber based QKD devices are already commercially available, but are fundamentally limited to distributing keys over a few hundred kilometers. To address this distance limitation, research QKD systems are being developed to exchange keys through free-space to satellites. This work considers practical challenges to building and testing both types of QKD devices. Firstly, we consider modeling and mission analysis for airborne demonstrations of QKD to stratospheric balloons and aircraft to simulate a satellite. Based on the mission parameters available for both platforms, we found aircraft platforms were more promising for testing prototype QKD satellite systems. We developed a mission planning tool to help design the flight geometries for testing the device. Next, we developed three new components for a QKD satellite prototype. The requirements for electro-optical devices in orbit are very different from lab environments, mandating new approaches to designing QKD devices. We developed a quad single photon detector package to meet the requirements for free-space links to low earth orbit. Moreover, we designed and built optical systems for analyzing the polarization of photons and an adaptive optics unit to increase the efficiency of collecting the encoded photons. All three devices were tested in conditions that simulated the time and loss of a satellite pass. Finally, we demonstrated a laser damage attack on a live commercial QKD system. Our attack injected additional optical power into the sender device to modify security-critical components. Specifically, our attack damaged the PIN diodes which monitor the encoded photon number, reducing their sensitivity or completely blinding them. Our damage could compromise the entire key, and was performed during system operation while raising no alarms. In summary, this work shows the trade-offs of testing QKD payloads on different airborne platforms, develops components for a satellite QKD payload, and demonstrates a security vulnerability in a commercial QKD system that can fully compromise the key. These results help address practical challenges to building QKD devices, improving the security of modern cryptography

NASA Tech Briefs, October 2006

Topics covered include: Protein Sensors Based on Optical Ring Resonators; Phase Sensor for Aligning a Segmented Telescope Mirror; Control Software for Advanced Video Guidance Sensor; Generating Control Commands From Gestures Sensed by EMG; Multiple-Flat-Panel System Displays Multidimensional Data; 3D X-Ray Luggage-Screening System; Probe Station and Near-Field Scanner for Testing Antennas; Photodetector Arrays for Multicolor Visible/Infrared Imaging; Semiconductor Bolometers Give Background-Limited Performance; Multichannel X-Band Dielectric-Resonator Oscillator; Automatic Alignment of Displacement-Measuring Interferometer; Earth Observing System Data Gateway; Power User Interface; Mercury Shopping Cart Interface; Cassini Archive Tracking System; Architecture Adaptive Computing Environment; Computing Fault Displacements from Surface Deformations; Oxygen-Permeable, Hydrophobic Membranes of Silanized alpha-Al2O3; SiC Composite Turbine Vanes; Retaining Device for the Interior Structure of a Spacecraft Payload; Tool for Torquing Circular Electrical-Connector Collars; System for Continuous Deaeration of Hydraulic Oil; Solar-Powered Cooler and Heater for an Automobile Interior; Improved Oxygen-Beam Texturing of Glucose-Monitoring Optics; Tool for Two Types of Friction Stir Welding; Stationary Apparatus Would Apply Forces of Walking to Feet; Instrument Would Detect and Collect Biological Aerosols; Boundary Condition for Modeling Semiconductor Nanostructures; Miniature Distillation Column for Producing LOX From Air; Even Illumination from Fiber-Optic-Coupled Laser Diodes; Optically Driven Deformable Mirrors; Algorithm for Automated Detection of Edges of Clouds; Exploiting Quantum Resonance to Solve Combinatorial Problems; Hybrid Terrain Database; On Release of Microbe-Laden Particles from Mars Landers; A Concept for Run-Time Support of the Chapel Language; Thermoelectric Inhomogeneities in (Ag(sub 1-y)SbTe2)(sub x)(PbTe)(sub 1-x); and Spacecraft Escape Capsule

NASA Tech Briefs, September 2008

Topics covered include: Nanotip Carpets as Antireflection Surfaces; Nano-Engineered Catalysts for Direct Methanol Fuel Cells; Capillography of Mats of Nanofibers; Directed Growth of Carbon Nanotubes Across Gaps; High-Voltage, Asymmetric-Waveform Generator; Magic-T Junction Using Microstrip/Slotline Transitions; On-Wafer Measurement of a Silicon-Based CMOS VCO at 324 GHz; Group-III Nitride Field Emitters; HEMT Amplifiers and Equipment for their On-Wafer Testing; Thermal Spray Formation of Polymer Coatings; Improved Gas Filling and Sealing of an HC-PCF; Making More-Complex Molecules Using Superthermal Atom/Molecule Collisions; Nematic Cells for Digital Light Deflection; Improved Silica Aerogel Composite Materials; Microgravity, Mesh-Crawling Legged Robots; Advanced Active-Magnetic-Bearing Thrust- Measurement System; Thermally Actuated Hydraulic Pumps; A New, Highly Improved Two-Cycle Engine; Flexible Structural-Health-Monitoring Sheets; Alignment Pins for Assembling and Disassembling Structures; Purifying Nucleic Acids from Samples of Extremely Low Biomass; Adjustable-Viewing-Angle Endoscopic Tool for Skull Base and Brain Surgery; UV-Resistant Non-Spore-Forming Bacteria From Spacecraft-Assembly Facilities; Hard-X-Ray/Soft-Gamma-Ray Imaging Sensor Assembly for Astronomy; Simplified Modeling of Oxidation of Hydrocarbons; Near-Field Spectroscopy with Nanoparticles Deposited by AFM; Light Collimator and Monitor for a Spectroradiometer; Hyperspectral Fluorescence and Reflectance Imaging Instrument; Improving the Optical Quality Factor of the WGM Resonator; Ultra-Stable Beacon Source for Laboratory Testing of Optical Tracking; Transmissive Diffractive Optical Element Solar Concentrators; Delaying Trains of Short Light Pulses in WGM Resonators; Toward Better Modeling of Supercritical Turbulent Mixing; JPEG 2000 Encoding with Perceptual Distortion Control; Intelligent Integrated Health Management for a System of Systems; Delay Banking for Managing Air Traffic; and Spline-Based Smoothing of Airfoil Curvatures

Advanced photonic sensors for industrial applications

380 p.En esta tesis se han desarrollado diversos sensores basados en fibra óptica cuya finalidad es ofrecer una alternativa o solución a las necesidades particulares de la industria. En este contexto, las fibras ópticas y la fotónica en general son especialmente atractivas gracias a características intrínsecas que poseen, como su pequeño tamaño y alta sensibilidad, por ejemplo, lo que ha aumentado el interés por parte del sector industrial en esta tecnología.En la primera parte de la tesis, se describe el proceso llevado a cabo para el diseño y fabricación de sensores ópticos para la medida sin contacto del parámetro llamado Tip Clearance (TC) en motores aeronáuticos. El TC consiste en medir la distancia (del orden de micrómetros) entre los álabes que están girando a altas revoluciones y la carcasa del motor, y, por tanto, es un parámetro de suma importancia para la industria aeronáutica tanto a nivel de seguridad como de eficiencia del motor. Dichos sensores fueron puestos a pruebas en el túnel de viento del Centro de Tecnologías Aeronáutcas (Zamudio, Bizkaia) con buenos resultados.En la segunda parte de la tesis se han diseñado y fabricado sensores basados en fibra multinúcleo particularizados específicamente para la medida de diversos parámetros como la temperatura,vibraciones, curvatura, bending, etc. que son de interés para la industria. Dichos sensores mostraron una alta sensibilidad, lo que unido a su simplicidad y pequeño tamaño los convierte en una alternativa interesante tanto para su integración en cadenas de producción como para su uso en test de validación