NASA Astrophysics Data System (ADS)
Hao, Yudong; Zhao, Yang; Li, Dacheng
1999-11-01
Grating projection 3D profilometry has three major problems that have to be handled with great care. They are local shadows, phase discontinuities and surface isolations. Carrying no information, shadow areas give us no clue about the profile there. Phase discontinuities often baffle phase unwrappers because they may be generated for several reasons difficult to distinguish. Spatial phase unwrapping will inevitably fail if the object under teste have surface isolations. In this paper, a complementary grating projection profilometry is reported, which attempts to tackle the three aforementioned problems simultaneously. This technique involves projecting two grating patterns form both sides of the CCD camera. Phase unwrapping is carried out pixel by pixel using the two phase maps based on the excess fraction method, which is immune to phase discontinuities or surface isolations. Complementary projection makes sure that no area in the visible volume of CCD is devoid of fringe information, although in some cases a small area of the reconstructed profile is of low accuracy compared with others. The system calibration procedures and measurement results are presented in detail, and possible improvement is discussed.
NASA Astrophysics Data System (ADS)
Chen, Chao; Gao, Nan; Wang, Xiangjun; Zhang, Zonghua
2018-03-01
Phase-based fringe projection methods have been commonly used for three-dimensional (3D) measurements. However, image saturation results in incorrect intensities in captured fringe pattern images, leading to phase and measurement errors. Existing solutions are complex. This paper proposes an adaptive projection intensity adjustment method to avoid image saturation and maintain good fringe modulation in measuring objects with a high range of surface reflectivities. The adapted fringe patterns are created using only one prior step of fringe-pattern projection and image capture. First, a set of phase-shifted fringe patterns with maximum projection intensity value of 255 and a uniform gray level pattern are projected onto the surface of an object. The patterns are reflected from and deformed by the object surface and captured by a digital camera. The best projection intensities corresponding to each saturated-pixel clusters are determined by fitting a polynomial function to transform captured intensities to projected intensities. Subsequently, the adapted fringe patterns are constructed using the best projection intensities at projector pixel coordinate. Finally, the adapted fringe patterns are projected for phase recovery and 3D shape calculation. The experimental results demonstrate that the proposed method achieves high measurement accuracy even for objects with a high range of surface reflectivities.
3D mapping of breast surface using digital fringe projection
NASA Astrophysics Data System (ADS)
Vairavan, Rajendaran; Retnasamy, Vithyacharan; Mohamad Shahimin, Mukhzeer; Sauli, Zaliman; Leng, Lai Siang; Wan Norhaimi, Wan Mokhzani; Marimuthu, Rajeswaran; Abdullah, Othman; Kirtsaeng, Supap
2017-02-01
Optical sensing technique has inherited non-contact nature for generating 3D surface mapping where its application ranges from MEMS component characterization, corrosion analysis, and vibration analysis. In particular, the digital fringe projection is utilized for 3D mapping of objects through the illumination of structured light for medical application extending from oral dental measurements, lower back deformation analysis, monitoring of scoliosis and 3D face reconstruction for biometric identification. However, the usage of digital fringe projection for 3D mapping of human breast is very minimal. Thus, this paper addresses the application of digital fringe projection for 3D mapping of breast surface based on total non-contact nature. In this work, phase shift method is utilized to perform the 3D mapping. The phase shifted fringe pattern are displayed through a digital projector onto the breast surface, and the distorted fringe patterns are captured by a CCD camera. A phase map is produced, and phase unwrapping was executed to obtain the 3D surface mapping of the breast. The surface height profile from 3D fringe projection was compared with the surface height measured by a direct method using electronic digital vernier caliper. Preliminary results showed the feasibility of digital fringe projection in providing a 3D mapping of breast and its application could be further extended for breast carcinoma detection.
Fiber-optic projected-fringe digital interferometry
NASA Technical Reports Server (NTRS)
Mercer, Carolyn R.; Beheim, Glenn
1990-01-01
A phase-stepped projected-fringe interferometer was developed which uses a closed-loop fiber-optic phase-control system to make very accurate surface profile measurements. The closed-loop phase-control system greatly reduces phase-stepping error, which is frequently the dominant source of error in digital interferometers. Two beams emitted from a fiber-optic coupler are combined to form an interference fringe pattern on a diffusely reflecting object. Reflections off of the fibers' output faces are used to create a phase-indicating signal for the closed-loop optical phase controller. The controller steps the phase difference between the two beams by pi/2 radians in order to determine the object's surface profile using a solid-state camera and a computer. The system combines the ease of alignment and automated data reduction of phase-stepping projected-fringe interferometry with the greatly improved phase-stepping accuracy of our closed-loop phase-controller. The system is demonstrated by measuring the profile of a plate containing several convex surfaces whose heights range from 15 to 25 micron high.
Airspace Technology Demonstration 2 (ATD-2) Phase 1 Concept of Use (ConUse)
NASA Technical Reports Server (NTRS)
Jung, Yoon; Engelland, Shawn; Capps, Richard; Coppenbarger, Rich; Hooey, Becky; Sharma, Shivanjli; Stevens, Lindsay; Verma, Savita; Lohr, Gary; Chevalley, Eric;
2018-01-01
This document presents an operational Concept of Use (ConUse) for the Phase 1 Baseline Integrated Arrival, Departure, and Surface (IADS) prototype system of NASA's Airspace Technology Demonstration 2 (ATD-2) sub-project, which began demonstration in 2017 at Charlotte Douglas International Airport (CLT). NASA is developing the IADS system under the ATD-2 sub-project in coordination with the Federal Aviation Administration (FAA) and aviation industry partners. The primary goal of ATD-2 sub-project is to improve the predictability and the operational efficiency of the air traffic system in metroplex environments, through the enhancement, development, and integration of the nation's most advanced and sophisticated arrival, departure, and surface prediction, scheduling, and management systems. The ATD-2 effort is a five-year research activity through 2020. The initial phase of the ATD-2 sub-project, which is the focus of this document, will demonstrate the Phase 1 Baseline IADS capability at CLT in 2017. The Phase 1 Baseline IADS capabilities of the ATD-2 sub-project consists of: (a) Strategic and tactical surface scheduling to improve efficiency and predictability of airport surface operations, (b) Tactical departure scheduling to enhance merging of departures into overhead traffic streams via accurate predictions of takeoff times and automated coordination between the Airport Traffic Control Tower (ATCT, or Tower) and the Air Route Traffic Control Center (ARTCC, or Center), (c) Improvements in departure surface demand predictions in Time Based Flow Management (TBFM), (d) A prototype Electronic Flight Data (EFD) system provided by the FAA via the Terminal Flight Data Manager (TFDM) early implementation effort, and (e) Improved situational awareness and demand predictions through integration with the Traffic Flow Management System (TFMS), TBFM, and TFDM (3Ts) for electronic data integration and exchange, and an on-screen dashboard displaying pertinent analytics in real-time. The surface scheduling and metering element of the capability is consistent with the Surface CDM Concept of Operations published in 2014 by the FAA Surface Operations Directorate.1 Upon successful demonstration of the Phase 1 Baseline IADS capability, follow-on demonstrations of the matured IADS traffic management capabilities will be conducted in the 2018-2020 timeframe. At the end of each phase of the demonstrations, NASA will transfer the ATD-2 sub-project technology to the FAA and industry partners.
A portable intra-oral scanner based on sinusoidal pattern of fast phase-shifting
NASA Astrophysics Data System (ADS)
Jan, Chia-Ming; Lin, Ying-Chieh
2016-03-01
This paper presented our current research about the intra-oral scanner made by MIRDC. Utilizing the sinusoidal pattern for fast phase-shifting technique to deal with 3D digitalization of human dental surface profile, the development of pseudo-phase shifting digital projection can easily achieve one type of full-field scanning instead of the common technique of the laser line scanning. Based on traditional Moiré method, we adopt projecting fringes and retrieve phase reconstruction to forward phase unwrapping. The phase difference between the plane and object can be exactly calculated from the desired fringe images, and the surface profile of object was probably reconstructed by using the phase differences information directly. According to our algorithm of space mapping between projections and capturing orientation exchange of our intra-oral scanning configuration, the system we made certainly can be proved to achieve the required accuracy of +/-10μm to deal with intra-oral scanning on the basis of utilizing active triangulation method. The final purpose aimed to the scanning of object surface profile with its size about 10x10x10mm3.
Laser sensor system documentation.
DOT National Transportation Integrated Search
2017-03-01
Phase 1 of TxDOT Project 0-6873, True Road Surface Deflection Measuring Device, developed a : laser sensor system based on several sensors mounted on a rigid beam. : This sensor system remains with CTR currently, as the project is moving into Phase 2...
A Non-Abelian Geometric Phase for Spin Systems
NASA Astrophysics Data System (ADS)
H M, Bharath; Boguslawski, Matthew; Barrios, Maryrose; Chapman, Michael
Berry's geometric phase has been used to characterize topological phase transitions. Recent works have addressed the question of whether generalizations of Berry's phase to mixed states can be used to characterize topological phase transitions. Berry's phase is essentially the geometric information stored in the overall phase of a quantum system. Here, we show that geometric information is also stored in the higher order spin moments of a quantum spin system. In particular, we show that when the spin vector of a quantum spin system with a spin 1 or higher is transported along a closed path inside the Bloch ball, the tensor of second moments picks up a geometric phase in the form of an SO(3) operator. Geometrically interpreting this phase is tantamount to defining a steradian angle for closed paths inside the Bloch ball. Typically the steradian angle is defined by projecting the path onto the surface of the Bloch ball. However, paths that pass through the center cannot be projected onto the surface. We show that the steradian angles of all paths, including those that pass through the center can be defined by projecting them onto a real projective plane, instead of a sphere. This steradian angle is equal to the geometric phase picked up by a spin system.
Phase-stepping fiber-optic projected fringe system for surface topography measurements
NASA Technical Reports Server (NTRS)
Mercer, Carolyn R. (Inventor); Beheim, Glenn (Inventor)
1992-01-01
A projected fringe interferometer for measuring the topography of an object is presented. The interferometer periodically steps the phase angle between a pair of light beams emanating from a common source. The steps are pi/2 radians (90 deg) apart, and at each step a video image of the fringes is recorded and stored. Photodetectors measure either the phase and theta of the beams or 2(theta). Either of the measures can be used to control one of the light beams so that the 90 deg theta is accurately maintained. A camera, a computer, a phase controller, and a phase modulator established closed-loop control of theta. Measuring the phase map of a flat surface establishes a calibration reference.
The Pliocene Model Intercomparison Project - Phase 2
NASA Astrophysics Data System (ADS)
Haywood, Alan; Dowsett, Harry; Dolan, Aisling; Rowley, David; Abe-Ouchi, Ayako; Otto-Bliesner, Bette; Chandler, Mark; Hunter, Stephen; Lunt, Daniel; Pound, Matthew; Salzmann, Ulrich
2016-04-01
The Pliocene Model Intercomparison Project (PlioMIP) is a co-ordinated international climate modelling initiative to study and understand climate and environments of the Late Pliocene, and their potential relevance in the context of future climate change. PlioMIP examines the consistency of model predictions in simulating Pliocene climate, and their ability to reproduce climate signals preserved by geological climate archives. Here we provide a description of the aim and objectives of the next phase of the model intercomparison project (PlioMIP Phase 2), and we present the experimental design and boundary conditions that will be utilised for climate model experiments in Phase 2. Following on from PlioMIP Phase 1, Phase 2 will continue to be a mechanism for sampling structural uncertainty within climate models. However, Phase 1 demonstrated the requirement to better understand boundary condition uncertainties as well as uncertainty in the methodologies used for data-model comparison. Therefore, our strategy for Phase 2 is to utilise state-of-the-art boundary conditions that have emerged over the last 5 years. These include a new palaeogeographic reconstruction, detailing ocean bathymetry and land/ice surface topography. The ice surface topography is built upon the lessons learned from offline ice sheet modelling studies. Land surface cover has been enhanced by recent additions of Pliocene soils and lakes. Atmospheric reconstructions of palaeo-CO2 are emerging on orbital timescales and these are also incorporated into PlioMIP Phase 2. New records of surface and sea surface temperature change are being produced that will be more temporally consistent with the boundary conditions and forcings used within models. Finally we have designed a suite of prioritized experiments that tackle issues surrounding the basic understanding of the Pliocene and its relevance in the context of future climate change in a discrete way.
Divergent surface and total soil moisture projections under global warming
Berg, Alexis; Sheffield, Justin; Milly, Paul C.D.
2017-01-01
Land aridity has been projected to increase with global warming. Such projections are mostly based on off-line aridity and drought metrics applied to climate model outputs but also are supported by climate-model projections of decreased surface soil moisture. Here we comprehensively analyze soil moisture projections from the Coupled Model Intercomparison Project phase 5, including surface, total, and layer-by-layer soil moisture. We identify a robust vertical gradient of projected mean soil moisture changes, with more negative changes near the surface. Some regions of the northern middle to high latitudes exhibit negative annual surface changes but positive total changes. We interpret this behavior in the context of seasonal changes in the surface water budget. This vertical pattern implies that the extensive drying predicted by off-line drought metrics, while consistent with the projected decline in surface soil moisture, will tend to overestimate (negatively) changes in total soil water availability.
NASA Astrophysics Data System (ADS)
Chi, Sheng; Lee, Shu-Sheng; Huang, Jen, Jen-Yu; Lai, Ti-Yu; Jan, Chia-Ming; Hu, Po-Chi
2016-04-01
As the progress of optical technologies, different commercial 3D surface contour scanners are on the market nowadays. Most of them are used for reconstructing the surface profile of mold or mechanical objects which are larger than 50 mm×50 mm× 50 mm, and the scanning system size is about 300 mm×300 mm×100 mm. There are seldom optical systems commercialized for surface profile fast scanning for small object size less than 10 mm×10 mm×10 mm. Therefore, a miniature optical system has been designed and developed in this research work for this purpose. Since the most used scanning method of such system is line scan technology, we have developed pseudo-phase shifting digital projection technology by adopting projecting fringes and phase reconstruction method. A projector was used to project a digital fringe patterns on the object, and the fringes intensity images of the reference plane and of the sample object were recorded by a CMOS camera. The phase difference between the plane and object can be calculated from the fringes images, and the surface profile of the object was reconstructed by using the phase differences. The traditional phase shifting method was accomplished by using PZT actuator or precisely controlled motor to adjust the light source or grating and this is one of the limitations for high speed scanning. Compared with the traditional optical setup, we utilized a micro projector to project the digital fringe patterns on the sample. This diminished the phase shifting processing time and the controlled phase differences between the shifted phases become more precise. Besides, the optical path design based on a portable device scanning system was used to minimize the size and reduce the number of the system components. A screwdriver section about 7mm×5mm×5mm has been scanned and its surface profile was successfully restored. The experimental results showed that the measurement area of our system can be smaller than 10mm×10mm, the precision reached to +/-10μm, and the scanning time for each surface of an object was less than 15 seconds. This has proved that our system own the potential to be a fast scanning scanner for small object surface profile scanning.
Suppression of contrast-related artefacts in phase-measuring structured light techniques
NASA Astrophysics Data System (ADS)
Burke, Jan; Zhong, Liang
2017-06-01
Optical metrology using phase measurements has benefited significantly from the introduction of phase-shifting methods, first in interferometry, then also in fringe projection and fringe reflection. As opposed to interferometry, the latter two techniques generally use a spatiotemporal phase-shifting approach: A sequence of fringe patterns with varying spacing is used, and a phase map of each is generated by temporal phase shifting, to allow unique assignments of projector or screen pixels to camera pixels. One ubiquitous problem with phase-shifting structured-light techniques is that phase artefacts appear near regions of the image where the modulation amplitude of the projected or reflected fringes changes abruptly, e.g. near dirt/dust particles on the surface in deflectometry or bright-dark object colour transitions in fringe projection. Near the bright-dark boundaries, responses in the phase maps appear that are not plausible as actual surface features. The phenomenon has been known for a long time but is usually ignored because it does not compromise the overall reliability of results. In deflectometry, however, often the objective is to find and classify small defects, and of course it is then important to distinguish between bogus phase responses caused by fringe modulation changes, and actual surface defects. We present, for what we believe is the first time, an analytical derivation of the error terms, study the parameters influencing the phase artefacts (in particular the fringe period), and suggest some simple algorithms to minimise them.
Projection of the Liquidus Surface of the Co - Sn - Bi System
NASA Astrophysics Data System (ADS)
Abilov, Ch. I.; Allazov, M. R.; Sadygova, S. G.
2016-11-01
The crystallization behavior of phases in alloys of the Co - Sn - Bi system is studied by the methods of differential thermal (DTA), x-ray phase (XRP) and x-ray diffraction (XRD) analyses and hardness measurement. The projection of the liquidus surface is plotted. The boundaries of layering, the development of the monovariant processes, and the coordinates of the nonvariant equilibrium compositions are determined. Compositions of (Co3Sn2)1 - x Bi x solid solutions suitable for the production of antifriction materials are suggested.
NASA Technical Reports Server (NTRS)
Brown, Christopher A.
1993-01-01
The approach of the project is to base the design of multi-function, reflective topographies on the theory that topographically dependent phenomena react with surfaces and interfaces at certain scales. The first phase of the project emphasizes the development of methods for understanding the sizes of topographic features which influence reflectivity. Subsequent phases, if necessary, will address the scales of interaction for adhesion and manufacturing processes. A simulation of the interaction of electromagnetic radiation, or light, with a reflective surface is performed using specialized software. Reflectivity of the surface as a function of scale is evaluated and the results from the simulation are compared with reflectivity measurements made on multi-function, reflective surfaces.
NASA Astrophysics Data System (ADS)
Haywood, Alan M.; Dowsett, Harry J.; Dolan, Aisling M.; Rowley, David; Abe-Ouchi, Ayako; Otto-Bliesner, Bette; Chandler, Mark A.; Hunter, Stephen J.; Lunt, Daniel J.; Pound, Matthew; Salzmann, Ulrich
2016-03-01
The Pliocene Model Intercomparison Project (PlioMIP) is a co-ordinated international climate modelling initiative to study and understand climate and environments of the Late Pliocene, as well as their potential relevance in the context of future climate change. PlioMIP examines the consistency of model predictions in simulating Pliocene climate and their ability to reproduce climate signals preserved by geological climate archives. Here we provide a description of the aim and objectives of the next phase of the model intercomparison project (PlioMIP Phase 2), and we present the experimental design and boundary conditions that will be utilized for climate model experiments in Phase 2. Following on from PlioMIP Phase 1, Phase 2 will continue to be a mechanism for sampling structural uncertainty within climate models. However, Phase 1 demonstrated the requirement to better understand boundary condition uncertainties as well as uncertainty in the methodologies used for data-model comparison. Therefore, our strategy for Phase 2 is to utilize state-of-the-art boundary conditions that have emerged over the last 5 years. These include a new palaeogeographic reconstruction, detailing ocean bathymetry and land-ice surface topography. The ice surface topography is built upon the lessons learned from offline ice sheet modelling studies. Land surface cover has been enhanced by recent additions of Pliocene soils and lakes. Atmospheric reconstructions of palaeo-CO2 are emerging on orbital timescales, and these are also incorporated into PlioMIP Phase 2. New records of surface and sea surface temperature change are being produced that will be more temporally consistent with the boundary conditions and forcings used within models. Finally we have designed a suite of prioritized experiments that tackle issues surrounding the basic understanding of the Pliocene and its relevance in the context of future climate change in a discrete way.
NASA Technical Reports Server (NTRS)
Haywood, Alan M.; Dowsett, Harry J.; Dolan, Aisling M.; Rowley, David; Abe-Ouchi, Ayako; Otto-Bliesner, Bette; Chandler, Mark A.; Hunter, Stephen J.; Lunt, Daniel J.; Pound, Matthew;
2016-01-01
The Pliocene Model Intercomparison Project (PlioMIP) is a co-ordinated international climate modelling initiative to study and understand climate and environments of the Late Pliocene, as well as their potential relevance in the context of future climate change. PlioMIP examines the consistency of model predictions in simulating Pliocene climate and their ability to reproduce climate signals preserved by geological climate archives. Here we provide a description of the aim and objectives of the next phase of the model intercomparison project (PlioMIP Phase 2), and we present the experimental design and boundary conditions that will be utilized for climate model experiments in Phase 2. Following on from PlioMIP Phase 1, Phase 2 will continue to be a mechanism for sampling structural uncertainty within climate models. However, Phase 1 demonstrated the requirement to better understand boundary condition uncertainties as well as uncertainty in the methodologies used for data-model comparison. Therefore, our strategy for Phase 2 is to utilize state-of-the-art boundary conditions that have emerged over the last 5 years. These include a new palaeogeographic reconstruction, detailing ocean bathymetry and land-ice surface topography. The ice surface topography is built upon the lessons learned from offline ice sheet modelling studies. Land surface cover has been enhanced by recent additions of Pliocene soils and lakes. Atmospheric reconstructions of palaeo-CO2 are emerging on orbital timescales, and these are also incorporated into PlioMIP Phase 2. New records of surface and sea surface temperature change are being produced that will be more temporally consistent with the boundary conditions and forcings used within models. Finally we have designed a suite of prioritized experiments that tackle issues surrounding the basic understanding of the Pliocene and its relevance in the context of future climate change in a discrete way.
Special Advanced Studies for Pollution Prevention. Delivery Order 0058: The Monitor - Spring 2000
2001-04-01
Process complexity ➨ Strippability ➨ Maturity ➨ Process type and chemistry ➨ Licensing requirements ➨ Vendor information ➨ Niplate 700 (Surface...Courses of Action 4 Identify & Evaluate Potential Alternatives 5 Select Best Alternative & Develop Project 6 Prioritize Projects by Commodity 7 Rank...Burden CS Priority Process Specific P2 OASolution Selection Solution Planning Solution Implementation Solution Evaluation Phase 2 Phase 3 Phase 1
Persistence of a surface state arc in the topologically trivial phase of MoTe2
NASA Astrophysics Data System (ADS)
Crepaldi, A.; Autès, G.; Sterzi, A.; Manzoni, G.; Zacchigna, M.; Cilento, F.; Vobornik, I.; Fujii, J.; Bugnon, Ph.; Magrez, A.; Berger, H.; Parmigiani, F.; Yazyev, O. V.; Grioni, M.
2017-01-01
The prediction of Weyl fermions in the low-temperature noncentrosymmetric 1 T' phase of MoTe2 still awaits clear experimental confirmation. Here, we report angle-resolved photoemission (ARPES) data and ab initio calculations that reveal a surface state arc dispersing between the valence and the conduction band, as expected for a Weyl semimetal. However, we find that the arc survives in the high-temperature centrosymmetric 1 T'' phase. Therefore, a surface Fermi arc is not an unambiguous fingerprint of a topologically nontrivial phase. We have also investigated the surface state spin texture of the 1 T' phase by spin-resolved ARPES, and identified additional topologically trivial spin-split states within the projected band gap at higher binding energies.
NASA Astrophysics Data System (ADS)
Jin, Chengying; Li, Dahai; Kewei, E.; Li, Mengyang; Chen, Pengyu; Wang, Ruiyang; Xiong, Zhao
2018-06-01
In phase measuring deflectometry, two orthogonal sinusoidal fringe patterns are separately projected on the test surface and the distorted fringes reflected by the surface are recorded, each with a sequential phase shift. Then the two components of the local surface gradients are obtained by triangulation. It usually involves some complicated and time-consuming procedures (fringe projection in the orthogonal directions). In addition, the digital light devices (e.g. LCD screen and CCD camera) are not error free. There are quantization errors for each pixel of both LCD and CCD. Therefore, to avoid the complex process and improve the reliability of the phase distribution, a phase extraction algorithm with five-frame crossed fringes is presented in this paper. It is based on a least-squares iterative process. Using the proposed algorithm, phase distributions and phase shift amounts in two orthogonal directions can be simultaneously and successfully determined through an iterative procedure. Both a numerical simulation and a preliminary experiment are conducted to verify the validity and performance of this algorithm. Experimental results obtained by our method are shown, and comparisons between our experimental results and those obtained by the traditional 16-step phase-shifting algorithm and between our experimental results and those measured by the Fizeau interferometer are made.
3D silicon breast surface mapping via structured light profilometry
NASA Astrophysics Data System (ADS)
Vairavan, R.; Ong, N. R.; Sauli, Z.; Kirtsaeng, S.; Sakuntasathien, S.; Shahimin, M. M.; Alcain, J. B.; Lai, S. L.; Paitong, P.; Retnasamy, V.
2017-09-01
Digital fringe projection technique is one of the promising optical methods for 3D surface imaging as it demonstrates non contact and non invasive characteristics. The potential of this technique matches the requirement for human body evaluation, as it is vital for disease diagnosis and for treatment option selection. Thus, the digital fringe projection has addressed this requirement with its wide clinical related application and studies. However, the application of this technique for 3D surface mapping of the breast is very minimal. Hence, in this work, the application of digital fringe projection for 3D breast surface mapping is reported. Phase shift fringe projection technique was utilized to perform the 3D breast surface mapping. Maiden results have confirmed the feasibility of using the digital fringe projection method for 3D surface mapping of the breast and it can be extended for breast cancer detection.
Partially filled Landau level at even denominators: A vortex metal with a Berry phase
NASA Astrophysics Data System (ADS)
You, Yizhi
2018-04-01
We develop a vortex metal theory for a partially filled Landau level at ν =1/2 n whose ground state contains a composite Fermi surface formed by the vortex of electrons. In the projected Landau-level limit, the composite Fermi surface contains a -π/n Berry phase. Such a fractional Berry phase is a consequence of Landau-level projection which produces the Girvin-MacDonald-Platzman [S. M. Girvin, A. H. MacDonald, and P. M. Platzman, Phys. Rev. B 33, 2481 (1986), 10.1103/PhysRevB.33.2481] guiding center algebra and embellishes an anomalous velocity to the equation of motion for the vortex metal. Further, we investigate a particle-hole symmetric bilayer system with ν1=1/2 n and ν2=1 -1/2 n at each layer, and demonstrate that the -π/n Berry phase on the composite Fermi surface leads to the suppression of 2 kf backscattering between the particle-hole partner bilayer, which could be a smoking gun to detect the fractional Berry phase. We also mention various instabilities and competing orders in such bilayer systems, including a Z4 n topological order phase driven by quantum criticality.
Highlight removal based on the regional-projection fringe projection method
NASA Astrophysics Data System (ADS)
Qi, Zhaoshuai; Wang, Zhao; Huang, Junhui; Xing, Chao; Gao, Jianmin
2018-04-01
In fringe projection profilometry, highlight usually causes the saturation and blooming in captured fringes and reduces the measurement accuracy. To solve the problem, a regional-projection fringe projection (RP-FP) method is proposed. Regional projection patterns (RP patterns) are projected onto the tested object surface to avoid the saturation and blooming. Then, an image inpainting technique is employed to reconstruct the missing phases in the captured RP patterns and a complete surface of the tested object is obtained. Experiments verified the effectiveness of the proposed method. The method can be widely used in industrial inspections and quality controlling in mechanical and manufacturing industries.
NASA's Plans for Developing Life Support and Environmental Monitoring and Control Systems
NASA Technical Reports Server (NTRS)
Lawson, B. Michael; Jan, Darrell
2006-01-01
Life Support and Monitoring have recently been reworked in response to the Vision for Space Exploration. The Exploration Life Support (ELS) Project has replaced the former Advanced Life Support Element of the Human Systems Research and Technology Office. Major differences between the two efforts include: the separation of thermal systems into a new stand alone thermal project, deferral of all work in the plant biological systems, relocation of food systems to another organization, an addition of a new project called habitation systems, and overall reduction in the number of technology options due to lower funding. The Advanced Environmental Monitoring and Control (AEMC) Element is retaining its name but changing its focus. The work planned in the ELS and AEMC projects is organized around the three major phases of the Exploration Program. The first phase is the Crew Exploration Vehicle (CEV). The ELS and AEMC projects will develop hardware for this short duration orbital and trans-lunar vehicle. The second phase is sortie landings on the moon. Life support hardware for lunar surface access vehicles including upgrades of the CEV equipment and technologies which could not be pursued in the first phase due to limited time and budget will be developed. Monitoring needs will address lunar dust issues, not applicable to orbital needs. The ELS and AEMC equipment is of short duration, but has different environmental considerations. The third phase will be a longer duration lunar outpost. This will consist of a new set of hardware developments better suited for long duration life support and associated monitoring needs on the lunar surface. The presentation will show the planned activities and technologies that are expected to be developed by the ELS and AEMC projects for these program phases.
NASA Astrophysics Data System (ADS)
Lino, A. C. L.; Dal Fabbro, I. M.
2008-04-01
The conception of a tridimensional digital model of solid figures and plant organs started from topographic survey of virtual surfaces [1], followed by topographic survey of solid figures [2], fruit surface survey [3] and finally the generation of a 3D digital model [4] as presented by [1]. In this research work, i.e. step number [4] tested objects included cylinders, cubes, spheres and fruits. A Ronchi grid named G1 was generated in a PC, from which other grids referred as G2, G3, and G4 were set out of phase by 1/4, 1/2 and 3/4 of period from G1. Grid G1 was then projected onto the samples surface. Projected grid was named Gd. The difference between Gd and G1 followed by filtration generated de moiré fringes M1 and so on, obtaining the fringes M2, M3 and M4 from Gd. Fringes are out of phase one from each other by 1/4 of period, which were processed by the Rising Sun Moiré software to produce packed phase and further on, the unpacked fringes. Tested object was placed on a goniometer and rotate to generate four surfaces topography. These four surveyed surfaces were assembled by means of a SCILAB software, obtaining a three column matrix, corresponding to the object coordinates xi, also having elevation values and coordinates corrected as well. The work includes conclusions on the reliability of the proposed method as well as the setup simplicity and of low cost.
Annual report, 1966-67, stream ecology phase of the Caspar Creek project
John W. DeWitt
1967-01-01
During the 1966 - June 30, 1967 fiscal year, calibration work on the stream ecology phase of the project continued along about the lines of last year's work. The emphasis was on determining the importance of stream canopy, particulary as it affects the amount of solar radiation being received at the water surface and on stream conditions influenced by the amount...
Evaluation of aggregate sections at Mn/ROAD
DOT National Transportation Integrated Search
2000-06-01
This project focuses on the second construction phase of the Minnesota Road Research facility (Mn/ROAD) and evaluates three typical, locally available, surfacing aggregates along with a rollover section from the initial phase for performance. The pro...
ENVISAT Land Surface Processes. Phase 2
NASA Technical Reports Server (NTRS)
vandenHurk, B. J. J. M.; Su, Z.; Verhoef, W.; Menenti, M.; Li, Z.-L.; Wan, Z.; Moene, A. F.; Roerink, G.; Jia, I.
2002-01-01
This is a progress report of the 2nd phase of the project ENVISAT- Land Surface Processes, which has a 3-year scope. In this project, preparative research is carried out aiming at the retrieval of land surface characteristics from the ENVISAT sensors MERIS and AATSR, for assimilation into a system for Numerical Weather Prediction (NWP). Where in the 1st phase a number of first shot experiments were carried out (aiming at gaining experience with the retrievals and data assimilation procedures), the current 2nd phase has put more emphasis on the assessment and improvement of the quality of the retrieved products. The forthcoming phase will be devoted mainly to the data assimilation experiments and the assessment of the added value of the future ENVISAT products for NWP forecast skill. Referring to the retrieval of albedo, leaf area index and atmospheric corrections, preliminary radiative transfer calculations have been carried out that should enable the retrieval of these parameters once AATSR and MERIS data become available. However, much of this work is still to be carried out. An essential part of work in this area is the design and implementation of software that enables an efficient use of MODTRAN(sub 4) radiative transfer code, and during the current project phase familiarization with these new components has been achieved. Significant progress has been made with the retrieval of component temperatures from directional ATSR-images, and the calculation of surface turbulent heat fluxes from these data. The impact of vegetation cover on the retrieved component temperatures appears manageable, and preliminary comparison of foliage temperature to air temperatures were encouraging. The calculation of surface fluxes using the SEBI concept,which includes a detailed model of the surface roughness ratio, appeared to give results that were in reasonable agreement with local measurements with scintillometer devices. The specification of the atmospheric boundary conditions appears a crucial component, and the use of first guess estimates from the RACMO models partially explains the success. Earlier data assimilation experiments with directional surface temperatures have been analysed a bit further and were also compared to results obtained from directly modeling the surface roughness ratio. Results between these calculations and the data assimilation results appeared well comparable, but a full test in which the surface roughness model is allowed to play a free role during the data assimilation process has yet to be carried out. A considerable number of tasks that have yet to be carried out during Phase 3 has been formulated.
Airspace Technology Demonstration 2 (ATD-2) Technology Description Document (TDD)
NASA Technical Reports Server (NTRS)
Ging, Andrew; Engelland, Shawn; Capps, Al; Eshow, Michelle; Jung, Yoon; Sharma, Shivanjli; Talebi, Ehsan; Downs, Michael; Freedman, Cynthia; Ngo, Tyler;
2018-01-01
This Technology Description Document (TDD) provides an overview of the technology for the Phase 1 Baseline Integrated Arrival, Departure, and Surface (IADS) prototype system of the National Aeronautics and Space Administration's (NASA) Airspace Technology Demonstration 2 (ATD-2) project, to be demonstrated beginning in 2017 at Charlotte Douglas International Airport (CLT). Development, integration, and field demonstration of relevant technologies of the IADS system directly address recommendations made by the Next Generation Air Transportation System (NextGen) Integration Working Group (NIWG) on Surface and Data Sharing and the Surface Collaborative Decision Making (Surface CDM) concept of operations developed jointly by the Federal Aviation Administration (FAA) and aviation industry partners. NASA is developing the IADS traffic management system under the ATD-2 project in coordination with the FAA, flight operators, CLT airport, and the National Air Traffic Controllers Association (NATCA). The primary goal of ATD-2 is to improve the predictability and operational efficiency of the air traffic system in metroplex environments, through the enhancement, development, and integration of the nation's most advanced and sophisticated arrival, departure, and surface prediction, scheduling, and management systems. The ATD-2 project is a 5-year research activity beginning in 2015 and extending through 2020. The Phase 1 Baseline IADS capability resulting from the ATD-2 research will be demonstrated at the CLT airport beginning in 2017. Phase 1 will provide the initial demonstration of the integrated system with strategic and tactical scheduling, tactical departure scheduling to an en route meter point, and an early implementation prototype of a Terminal Flight Data Manager (TFDM) Electronic Flight Data (EFD) system. The strategic surface scheduling element of the capability is consistent with the Surface CDM Concept of Operations published in 2014 by the FAA Surface Operations Directorate.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dehoff, Ryan R.; List, III, Frederick Alyious; Carver, Keith
ORNL Manufacturing Demonstration Facility worked with ECM Technologies LLC to investigate the use of precision electro-chemical machining technology to polish the surface of parts created by Arcam electron beam melting. The goals for phase one of this project have been met. The project goal was to determine whether electro-chemical machining is a viable method to improve the surface finish of Inconel 718 parts fabricated using the Arcam EBM method. The project partner (ECM) demonstrated viability for parts of both simple and complex geometry. During the course of the project, detailed process knowledge was generated. This project has resulted in themore » expansion of United States operations for ECM Technologies.« less
Scanning moiré and spatial-offset phase-stepping for surface inspection of structures
NASA Astrophysics Data System (ADS)
Yoneyama, S.; Morimoto, Y.; Fujigaki, M.; Ikeda, Y.
2005-06-01
In order to develop a high-speed and accurate surface inspection system of structures such as tunnels, a new surface profile measurement method using linear array sensors is studied. The sinusoidal grating is projected on a structure surface. Then, the deformed grating is scanned by linear array sensors that move together with the grating projector. The phase of the grating is analyzed by a spatial offset phase-stepping method to perform accurate measurement. The surface profile measurements of the wall with bricks and the concrete surface of a structure are demonstrated using the proposed method. The change of geometry or fabric of structures and the defects on structure surfaces can be detected by the proposed method. It is expected that the surface profile inspection system of tunnels measuring from a running train can be constructed based on the proposed method.
NASA Astrophysics Data System (ADS)
Zhang, Yujia; Yilmaz, Alper
2016-06-01
Surface reconstruction using coded structured light is considered one of the most reliable techniques for high-quality 3D scanning. With a calibrated projector-camera stereo system, a light pattern is projected onto the scene and imaged by the camera. Correspondences between projected and recovered patterns are computed in the decoding process, which is used to generate 3D point cloud of the surface. However, the indirect illumination effects on the surface, such as subsurface scattering and interreflections, will raise the difficulties in reconstruction. In this paper, we apply maximum min-SW gray code to reduce the indirect illumination effects of the specular surface. We also analysis the errors when comparing the maximum min-SW gray code and the conventional gray code, which justifies that the maximum min-SW gray code has significant superiority to reduce the indirect illumination effects. To achieve sub-pixel accuracy, we project high frequency sinusoidal patterns onto the scene simultaneously. But for specular surface, the high frequency patterns are susceptible to decoding errors. Incorrect decoding of high frequency patterns will result in a loss of depth resolution. Our method to resolve this problem is combining the low frequency maximum min-SW gray code and the high frequency phase shifting code, which achieves dense 3D reconstruction for specular surface. Our contributions include: (i) A complete setup of the structured light based 3D scanning system; (ii) A novel combination technique of the maximum min-SW gray code and phase shifting code. First, phase shifting decoding with sub-pixel accuracy. Then, the maximum min-SW gray code is used to resolve the ambiguity resolution. According to the experimental results and data analysis, our structured light based 3D scanning system enables high quality dense reconstruction of scenes with a small number of images. Qualitative and quantitative comparisons are performed to extract the advantages of our new combined coding method.
NWR (National Weather Service) voice synthesis project, phase 1
NASA Astrophysics Data System (ADS)
Sampson, G. W.
1986-01-01
The purpose of the NOAA Weather Radio (NWR) Voice Synthesis Project is to provide a demonstration of the current voice synthesis technology. Phase 1 of this project is presented, providing a complete automation of an hourly surface aviation observation for broadcast over NWR. In examining the products currently available on the market, the decision was made that synthetic voice technology does not have the high quality speech required for broadcast over the NWR. Therefore the system presented uses the phrase concatenation type of technology for a very high quality, versatile, voice synthesis system.
The Pilot Phase of the Global Soil Wetness Project Phase 3
NASA Astrophysics Data System (ADS)
Kim, H.; Oki, T.
2015-12-01
After the second phase of the Global Soil Wetness Project (GSWP2) as an early global continuous gridded multi-model analysis, a comprehensive set of land surface fluxes and state variables became available. It has been broadly utilized in the hydrology community, and its success has evolved to take advantages of recent scientific progress and to extend the relatively short time span (1986-1995) of the previous project. In the third phase proposed here (GSWP3), an extensive set of quantities for hydro-energy-eco systems will be produced to investigate their long-term (1901-2010) changes. The energy-water-carbon cycles and their interactions are also examined subcomponent-wise with appropriate model verifications in ensemble land simulations. In this study, the preliminary results and problems found from the first round analysis of the GSWP3 pilot study are shown. Also, it is discussed how the global offline simulation activity contributes to wider communities and a bigger scope such as Climate Model Intercomparison Project Phase 6 (CMIP6).
Topometry of technical and biological objects by fringe projection
NASA Astrophysics Data System (ADS)
Windecker, R.; Tiziani, H. J.
1995-07-01
Fringe projection is a fast and accurate technique for obtaining the topometry of a wide range of surfaces. Here some features of the principle are described, together with the possibilities of adapting this technique for the measurement of vaulted surfaces. We discuss various methods of phase evaluation and compare them with simulated computer data to obtain the resolution limits. Under certain restrictions a semispatial algorithm, called the modified Fourier analysis algorithm, gives the best results. One special subject of interest is the application of fringe projection for the measurement of the three-dimensional surface of the cornea. First results of in vivo measurements are presented.
Zhao, Yue; Zhu, Dianwen; Baikejiang, Reheman; Li, Changqing
2015-11-10
This work introduces a fast, low-cost, robust method based on fringe pattern and phase shifting to obtain three-dimensional (3D) mouse surface geometry for fluorescence molecular tomography (FMT) imaging. We used two pico projector/webcam pairs to project and capture fringe patterns from different views. We first calibrated the pico projectors and the webcams to obtain their system parameters. Each pico projector/webcam pair had its own coordinate system. We used a cylindrical calibration bar to calculate the transformation matrix between these two coordinate systems. After that, the pico projectors projected nine fringe patterns with a phase-shifting step of 2π/9 onto the surface of a mouse-shaped phantom. The deformed fringe patterns were captured by the corresponding webcam respectively, and then were used to construct two phase maps, which were further converted to two 3D surfaces composed of scattered points. The two 3D point clouds were further merged into one with the transformation matrix. The surface extraction process took less than 30 seconds. Finally, we applied the Digiwarp method to warp a standard Digimouse into the measured surface. The proposed method can reconstruct the surface of a mouse-sized object with an accuracy of 0.5 mm, which we believe is sufficient to obtain a finite element mesh for FMT imaging. We performed an FMT experiment using a mouse-shaped phantom with one embedded fluorescence capillary target. With the warped finite element mesh, we successfully reconstructed the target, which validated our surface extraction approach.
Seasonal variability of near surface soil water and groundwater tables in Florida : phase II.
DOT National Transportation Integrated Search
2008-01-01
The seasonal high groundwater table (SHGWT) is a critical measure for design projects requiring : surface water permits including roadway design and detention or retention pond design. Accurately : measuring and, more importantly, predicting water ta...
Phase compensation with fiber optic surface profile acquisition and reconstruction system
NASA Astrophysics Data System (ADS)
Bo, En; Duan, Fajie; Feng, Fan; Lv, Changrong; Xiao, Fu; Huang, Tingting
2015-02-01
A fiber-optic sinusoidal phase modulating (SPM) interferometer was proposed for the acquisition and reconstruction of three-dimensional (3-D) surface profile. Sinusoidal phase modulation was induced by controlling the injection current of light source. The surface profile was constructed on the basis of fringe projection. Fringe patterns are vulnerable to external disturbances such as mechanical vibration and temperature fluctuation, which cause phase drift in the interference signal and decrease measuring accuracy. A closed-loop feedback phase compensation system was built. In the subsystem, the initial phase of the interference signal, which was caused by the initial optical path difference between interference arms, could be demodulated using phase generated carrier (PGC) method and counted out using coordinated rotation digital computer (CORDIC) , then a compensation voltage was generated for the PZT driver. The bias value of external disturbances superimposed on fringe patterns could be reduced to about 50 mrad, and the phase stability for interference fringes was less than 6 mrad. The feasibility for real-time profile measurement has been verified.
Surface to bulk Fermi arcs via Weyl nodes as topological defects
Kim, Kun Woo; Lee, Woo-Ram; Kim, Yong Baek; Park, Kwon
2016-01-01
A hallmark of Weyl semimetal is the existence of surface Fermi arcs. An intriguing question is what determines the connectivity of surface Fermi arcs, when multiple pairs of Weyl nodes are present. To answer this question, we show that the locations of surface Fermi arcs are predominantly determined by the condition that the Zak phase integrated along the normal-to-surface direction is . The Zak phase can reveal the peculiar topological structure of Weyl semimetal directly in the bulk. Here, we show that the winding of the Zak phase around each projected Weyl node manifests itself as a topological defect of the Wannier–Stark ladder, energy eigenstates under an electric field. Remarkably, this leads to bulk Fermi arcs, open-line segments in the bulk spectra. Bulk Fermi arcs should exist in conjunction with surface counterparts to conserve the Weyl fermion number under an electric field, which is supported by explicit numerical evidence. PMID:27845342
Project M: Scale Model of Lunar Landing Site of Apollo 17
NASA Technical Reports Server (NTRS)
O'Brien, Hollie; Crain, Timothy P.
2010-01-01
The basis of the project was creating a scale model representation of the Apollo 17 lunar landing site. Vital components included surface slope characteristics, crater sizes and locations, prominent rocks, and lighting conditions. The model was made for Project M support when evaluating approach and terminal descent as well as when planning surface operations with respect to the terrain. The project had five main mi lestones during the length of the project. The first was examining the best method to use to re-create the Apollo 17 landing site and then reviewing research fmdings with Dr. Tim Crain and EO staff which occurred on June 25, 2010 at a meeting. The second step was formulating a construction plan, budget, and schedule and then presenting the plan for authority to proceed which occurred on July 6,2010. The third part was building a prototype to test materials and building processes which were completed by July 13, 2010. Next was assembling the landing site model and presenting a mid-term construction status report on July 29, 2010. The fifth and final milestone was demonstrating the model and presenting an exit pitch which happened on August 4, 2010. The project was very technical: it needed a lot of research about moon topography, lighting conditions and angles of the sun on the moon, Apollo 17, and Autonomous Landing and Hazard Avoidance Technology (ALHAT), before starting the actual building process. This required using Spreadsheets, searching internet sources and conducting personal meetings with project representatives. This information assisted the interns in deciding the scale of the model with respect to cracks, craters and rocks and their relative sizes as the objects mentioned could interfere with any of the Lunar Landers: Apollo, Project M and future Landers. The project concluded with the completion of a three dimensional scale model of the Apollo 17 Lunar landing site. This model assists Project M members because they can now visualize approach phase, terminal descent phase, and surface phase operations on the physical model. The project had an additional requirement that was also satisfied: the granite table the model was placed on must be returnable to its original condition if needed in the future.
Introduction of the 2nd Phase of the Integrated Hydrologic Model Intercomparison Project
NASA Astrophysics Data System (ADS)
Kollet, Stefan; Maxwell, Reed; Dages, Cecile; Mouche, Emmanuel; Mugler, Claude; Paniconi, Claudio; Park, Young-Jin; Putti, Mario; Shen, Chaopeng; Stisen, Simon; Sudicky, Edward; Sulis, Mauro; Ji, Xinye
2015-04-01
The 2nd Phase of the Integrated Hydrologic Model Intercomparison Project commenced in June 2013 with a workshop at Bonn University funded by the German Science Foundation and US National Science Foundation. Three test cases were defined and compared that are available online at www.hpsc-terrsys.de including a tilted v-catchment case; a case called superslab based on multiple slab-heterogeneities in the hydraulic conductivity along a hillslope; and the Borden site case, based on a published field experiment. The goal of this phase is to further interrogate the coupling of surface-subsurface flow implemented in various integrated hydrologic models; and to understand and quantify the impact of differences in the conceptual and technical implementations on the simulation results, which may constitute an additional source of uncertainty. The focus has been broadened considerably including e.g. saturated and unsaturated subsurface storages, saturated surface area, ponded surface storage in addition to discharge, and pressure/saturation profiles and cross-sections. Here, first results are presented and discussed demonstrating the conceptual and technical challenges in implementing essentially the same governing equations describing highly non-linear moisture redistribution processes and surface-groundwater interactions.
Fringe-period selection for a multifrequency fringe-projection phase unwrapping method
NASA Astrophysics Data System (ADS)
Zhang, Chunwei; Zhao, Hong; Jiang, Kejian
2016-08-01
The multi-frequency fringe-projection phase unwrapping method (MFPPUM) is a typical phase unwrapping algorithm for fringe projection profilometry. It has the advantage of being capable of correctly accomplishing phase unwrapping even in the presence of surface discontinuities. If the fringe frequency ratio of the MFPPUM is too large, fringe order error (FOE) may be triggered. FOE will result in phase unwrapping error. It is preferable for the phase unwrapping to be kept correct while the fewest sets of lower frequency fringe patterns are used. To achieve this goal, in this paper a parameter called fringe order inaccuracy (FOI) is defined, dominant factors which may induce FOE are theoretically analyzed, a method to optimally select the fringe periods for the MFPPUM is proposed with the aid of FOI, and experiments are conducted to research the impact of the dominant factors in phase unwrapping and demonstrate the validity of the proposed method. Some novel phenomena are revealed by these experiments. The proposed method helps to optimally select the fringe periods and detect the phase unwrapping error for the MFPPUM.
NASA Astrophysics Data System (ADS)
Carrer, D.; Pinault, F.; Ceamanos, X.; Meurey, C.; Moparthy, S.; Swinnen, E.; Trigo, I.
2017-12-01
The two space programs of EUMETSAT (project CDOP3, LSA-SAF) and ECMWF (the Copernicus Climate Change Service; C3S_312a Lot9) provide (or will provide) added-value satellite products for the meteorological and environmental science communities, especially in the fields of climate modeling, environmental management, natural hazards management, and climate change detection. The EUMETSAT/LSA-SAF project started in 1999 with research and development activities. The Third Continuous Development and Operations Phase (CDOP-3) starts in March 2017 and will end in 2022. This project uses instruments on board European satellites that were, or will be, launched between 2004 and 2022. Unlike the LSA-SAF, the COPERNICUS/C3S_312a project has no NRT constraint. Its first phase started in november 2016. One of the major objective of the COPERNICUS/C3S_312a project is to harmonize datasets from various sensors in order to provide consistent and continuous ECV products from the 80's until now.Presently, the delivered operational products comprise several surface albedo products using data from various space missions (METEOSAT, NOAA, METOP, …). We present here the portfolio of the surface albedo products that are disseminated with an operational status. Their characteristics and accuracy are detailed here after. Also we will present the development plan to produce long-term re-analysis and to prepare the arrival of the next generation of satellite (MTG, EPS-SG, ...). This work will lead in 2018 to 40 years of products characterizing the albedo properties of the surface. These programs provide a great opportunity to monitor and identify human-induced climate change since consistent production of data sets is guaranteed until at least 2022.
Computer-Generated Phase Diagrams for Binary Mixtures.
ERIC Educational Resources Information Center
Jolls, Kenneth R.; And Others
1983-01-01
Computer programs that generate projections of thermodynamic phase surfaces through computer graphics were used to produce diagrams representing properties of water and steam and the pressure-volume-temperature behavior of most of the common equations of state. The program, program options emphasizing thermodynamic features of interest, and…
An integrated optical CO2 sensor. Phase 0: Design and fabrication of critical elements
NASA Technical Reports Server (NTRS)
Murphy, Michael C.; Kelly, Kevin W.; Li, B. Q.; Ma, EN; Wang, Wanjun; Vladimirsky, Yuli; Vladimirsky, Olga
1994-01-01
Significant progress has been made toward all of the goals for the first phase of the project short of actual fabrication of a light path. Two alternative approaches to fabricating gold mirrors using the basic LIGA process were developed, one using electroplated solid gold mirrors and the second using gold plated over a nickel base. A new method of fabrication, the transfer mask process, was developed and demonstrated. Analysis of the projected surface roughness and beam divergence effects was completed. With gold surface with low surface roughness scattering losses are expected to be insignificant. Beam divergence due to diffraction will require a modification of the original design, but should be eliminated by fabricating mirrors 1000 mu m in height by 1000 mu m in width and using a source with an initial beam radius greater than 300 mu m. This may eliminate any need for focusing optics. Since the modified design does not affect the mask layout, ordering of the mask and fabrication of the test structures can begin immediately at the start of Phase 1.
NASA Astrophysics Data System (ADS)
Bell, Lisa Y.; Boles, Walter; Smith, Alvin
1991-08-01
In an environment of intense competition for Federal funding, the U.S. space research community is responsible for developing a feasible, cost-effective approach to establishing a surface base on the moon to fulfill long-term Government objectives. This report presents the results of a construction operations analysis of two lunar scenarios provided by the National Aeronautics and Space Administration (NASA). Activities necessary to install the lunar base surface elements are defined and scheduled, based on the productivities and availability of the base resources allocated to the projects depicted in each scenario. The only construction project in which the required project milestones were not completed within the nominal timeframe was the initial startup phase of NASA's FY89 Lunar Evolution Case Study (LECS), primarily because this scenario did not include any Earth-based telerobotic site preparation before the arrival of the first crew. The other scenario analyzed. Reference Mission A from NASA's 90-Day Study of the Human Exploration of the Moon and Mars, did use telerobotic site preparation before the manned phase of the base construction. Details of the analysis for LECS are provided, including spreadsheets indicating quantities of work and Gantt charts depicting the general schedule for the work. This level of detail is not presented for the scenario based on the 90-Day Study because many of the projects include the same (or similar) surface elements and facilities.
Leaf cuticle topography retrieved by using fringe projection
NASA Astrophysics Data System (ADS)
Martínez, Amalia; Rayas, J. A.; Cordero, Raúl R.; Balieiro, Daniela; Labbe, Fernando
2012-02-01
The combination (often referred to as phase-stepping profilometry, PSP) of the fringe projection technique and the phase-stepping method allowed us to retrieve topographic maps of cuticles isolated from the abaxial surface of leaves; these were in turn sampled from an apple tree ( Malus domestica) of the variety Golden Delicious. The topographic maps enabled us to assess the natural features on the illuminated surface and also to detect the whole-field spatial variations in the thickness of the cuticle. Most of our attention was paid to retrieve the highly-resolved elevation information from the cuticle surface, which included the trace (in the order of tens of micrometers) left by ribs and veins. We expect that the PSP application for retrieving the cuticle topography will facilitate further studies on the dispersion and coverage of state-of-the-art agrochemical compounds meant to improve the defending properties of the cuticle. Methodological details are provided below.
Yun, Sungdae; Kyriakos, Walid E; Chung, Jun-Young; Han, Yeji; Yoo, Seung-Schik; Park, Hyunwook
2007-03-01
To develop a novel approach for calculating the accurate sensitivity profiles of phased-array coils, resulting in correction of nonuniform intensity in parallel MRI. The proposed intensity-correction method estimates the accurate sensitivity profile of each channel of the phased-array coil. The sensitivity profile is estimated by fitting a nonlinear curve to every projection view through the imaged object. The nonlinear curve-fitting efficiently obtains the low-frequency sensitivity profile by eliminating the high-frequency image contents. Filtered back-projection (FBP) is then used to compute the estimates of the sensitivity profile of each channel. The method was applied to both phantom and brain images acquired from the phased-array coil. Intensity-corrected images from the proposed method had more uniform intensity than those obtained by the commonly used sum-of-squares (SOS) approach. With the use of the proposed correction method, the intensity variation was reduced to 6.1% from 13.1% of the SOS. When the proposed approach was applied to the computation of the sensitivity maps during sensitivity encoding (SENSE) reconstruction, it outperformed the SOS approach in terms of the reconstructed image uniformity. The proposed method is more effective at correcting the intensity nonuniformity of phased-array surface-coil images than the conventional SOS method. In addition, the method was shown to be resilient to noise and was successfully applied for image reconstruction in parallel imaging.
IPRT polarized radiative transfer model intercomparison project - Phase A
NASA Astrophysics Data System (ADS)
Emde, Claudia; Barlakas, Vasileios; Cornet, Céline; Evans, Frank; Korkin, Sergey; Ota, Yoshifumi; Labonnote, Laurent C.; Lyapustin, Alexei; Macke, Andreas; Mayer, Bernhard; Wendisch, Manfred
2015-10-01
The polarization state of electromagnetic radiation scattered by atmospheric particles such as aerosols, cloud droplets, or ice crystals contains much more information about the optical and microphysical properties than the total intensity alone. For this reason an increasing number of polarimetric observations are performed from space, from the ground and from aircraft. Polarized radiative transfer models are required to interpret and analyse these measurements and to develop retrieval algorithms exploiting polarimetric observations. In the last years a large number of new codes have been developed, mostly for specific applications. Benchmark results are available for specific cases, but not for more sophisticated scenarios including polarized surface reflection and multi-layer atmospheres. The International Polarized Radiative Transfer (IPRT) working group of the International Radiation Commission (IRC) has initiated a model intercomparison project in order to fill this gap. This paper presents the results of the first phase A of the IPRT project which includes ten test cases, from simple setups with only one layer and Rayleigh scattering to rather sophisticated setups with a cloud embedded in a standard atmosphere above an ocean surface. All scenarios in the first phase A of the intercomparison project are for a one-dimensional plane-parallel model geometry. The commonly established benchmark results are available at the IPRT website.
Miyano, Naoki; Inoue, Yuuki; Teramura, Yuji; Fujii, Keisuke; Tsumori, Fujio; Iwata, Hiroo; Kotera, Hidetoshi
2008-07-01
In the diffusional phase transformation of two-phase alloys, the new phase precipitates form the matrix phase at specific temperatures, followed by the formation of a mixed microstructure comprising the precipitate and the matrix. It has been found that by specific chemical-etching treatment, the precipitate in Fe-25Cr-6Ni alloy projects substantially and clusters at the surface. The configuration of the precipitate has an extremely high aspect ratio: it is several microns in width and several tens of microns in length (known as micron-spiked). This study targets the development of a gene transfer device with a micro-spike produced based on the self-organization phenomenon of the Fe-25Cr-6Ni alloy. With this spike-projected device, we tried to efficiently transfer plasmid DNA into adherent cells by electric pulse-triggered gene transfer using a plasmid-loaded electrode (electroporation-based reverse transfection). The spiked structure was applied to a substrate of the device to allow efficient gene transfer into adherent cells, although the general substrate was flat and had a smooth surface. The results suggest that this unique spike-projected device has potential applications in gene transfer devices for the analysis of the human genome in the post-genome period.
SELDI Validation Study Phase II — EDRN Public Portal
This project –A Comprehensive Program for the Validation of Prostate Cancer Early Detection with Novel Protein Identification Techniques -- is divided into three phases. The goal of Phase I was to assess the reproducibility and portability of Surface-Enhanced Laser Desorption and Ionization time-of-flight mass spectrometry (SELDI-TOF-MS) using protein profiles generated from serum. Phase I was recently successfully completed at six institutions using a single source of pooled sera.
This research project will identify specific chemical and physical characteristics of activated carbon surfaces that promote the removal of gas-phase, polar organic pollutants. It is expected that basic and acidic functional groups will influence aldehyde adsorption through di...
2011-09-30
simulation provides boundary condition to the SPH simulation in a sub- domain. For the test with surface wave propagation, the free surface and the...This project aims at developing an advanced simulation tool for multi-fluids free - surface flows that can be used to study the fundamental physics...of horizontal velocity(normalized by wave phase speed c) obtained from SPH simulation and the corresponding free surface obtained from LSM
Pashaei, Ali; Bayer, Jason; Meillet, Valentin; Dubois, Rémi; Vigmond, Edward
2015-03-01
To show how atrial fibrillation rotor activity on the heart surface manifests as phase on the torso, fibrillation was induced on a geometrically accurate computer model of the human atria. The Hilbert transform, time embedding, and filament detection were compared. Electrical activity on the epicardium was used to compute potentials on different surfaces from the atria to the torso. The Hilbert transform produces erroneous phase when pacing for longer than the action potential duration. The number of phase singularities, frequency content, and the dominant frequency decreased with distance from the heart, except for the convex hull. Copyright © 2015 Elsevier Inc. All rights reserved.
Fringe projection application for surface variation analysis on helical shaped silicon breast
NASA Astrophysics Data System (ADS)
Vairavan, R.; Ong, N. R.; Sauli, Z.; Shahimin, M. M.; Kirtsaeng, S.; Sakuntasathien, S.; Alcain, J. B.; Paitong, P.; Retnasamy, V.
2017-09-01
Breast carcinoma is rated as a second collective cause of cancer associated death among adult females. Detection of the disease at an early stage would enhance the chance for survival. Established detection methods such as mammography, ultrasound and MRI are classified as non invasive breast cancer detection modality, but however they are not entire non-invasive as physical contact still occurs to the breast. Thus requirement for a complete non invasive and non contact is evident. Therefore, in this work, a novel application of digital fringe projection for early detection of breast cancer based on breast surface analysis is reported. Phase shift fringe projection technique and pixel tracing method was utilized to analyze the breast surface change due to the incidence of breast lump. Results have shown that the digital fringe projection is capable in detecting the existence of 1 cm sized lump within the breast sample.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Finley, Robert; Payne, William; Kirksey, Jim
2015-06-01
The Midwest Geological Sequestration Consortium (MGSC) has partnered with Archer Daniels Midland Company (ADM) and Schlumberger Carbon Services to conduct a large-volume, saline reservoir storage project at ADM’s agricultural products processing complex in Decatur, Illinois. The Development Phase project, named the Illinois Basin Decatur Project (IBDP) involves the injection of 1 million tonnes of carbon dioxide (CO 2) into a deep saline formation of the Illinois Basin over a three-year period. This report focuses on objectives, execution, and lessons learned/unanticipated results from the site development (relating specifically to surface equipment), operations, and the site closure plan.
Predicting Hidden bulk phases in Sr3Ru2O7 from surface phases
NASA Astrophysics Data System (ADS)
Rivero, Pablo; Chen, Chen; Jin, Roying; Meunier, Vincent; Plummer, E. W.; Shelton, William
Double-layered Sr3Ru2O7 has received phenomenal attention as it exhibits an overabundance of exotic phases when perturbed. Recently it has been shown that the surface of this material displays significantly different properties than in the bulk due to the surface induced tilt of the RuO6 octahedra. Here we report detailed first principles calculations of the surface structure, and the structure property relationship. Tilt of the octahedra drive the surface into a much less conducting state than in the bulk due in part to the different electronic properties of the two Ru atoms in the first RuO2 layer of the bilayer. The broken symmetry at the surface causes a tilt and enhanced rotation of the octahedra only present in the first (surface) bilayer. Theoretically the surface is ferromagnetically ordered but the stability with respect to the antiferromagnetic phase is small ( = 11 meV). We have calculated the bulk properties under uniaxial pressure, which induces a tilt and drives the bulk into an antiferromagnetic-insulating state. Support of this project came from DoE contract No. DE-SCOO12432 and the Louisiana Board of Regents. V. M. acknowledges support from New York State under NYSTAR program C080117.
Geologic Mapping of the Olympus Mons Volcano, Mars
NASA Technical Reports Server (NTRS)
Bleacher, J. E.; Williams, D. A.; Shean, D.; Greeley, R.
2012-01-01
We are in the third year of a three-year Mars Data Analysis Program project to map the morphology of the Olympus Mons volcano, Mars, using ArcGIS by ESRI. The final product of this project is to be a 1:1,000,000-scale geologic map. The scientific questions upon which this mapping project is based include understanding the volcanic development and modification by structural, aeolian, and possibly glacial processes. The project s scientific objectives are based upon preliminary mapping by Bleacher et al. [1] along a approx.80-km-wide north-south swath of the volcano corresponding to High Resolution Stereo Camera (HRSC) image h0037. The preliminary project, which covered approx.20% of the volcano s surface, resulted in several significant findings, including: 1) channel-fed lava flow surfaces are areally more abundant than tube-fed surfaces by a ratio of 5:1, 2) channel-fed flows consistently embay tube-fed flows, 3) lava fans appear to be linked to tube-fed flows, 4) no volcanic vents were identified within the map region, and 5) a Hummocky unit surrounds the summit and is likely a combination of non-channelized flows, dust, ash, and/or frozen volatiles. These results led to the suggestion that the volcano had experienced a transition from long-lived tube-forming eruptions to more sporadic and shorter-lived, channel-forming eruptions, as seen at Hawaiian volcanoes between the tholeiitic shield building phase (Kilauea to Mauna Loa) and alkalic capping phase (Hualalai and Mauna Kea).
Surface Wave Propagation on a Laterally Heterogeneous Earth
NASA Astrophysics Data System (ADS)
Tromp, Jeroen
1992-01-01
Love and Rayleigh waves propagating on the surface of the Earth exhibit path, phase and amplitude anomalies as a result of the lateral heterogeneity of the mantle. In the JWKB approximation, these anomalies can be determined by tracing surface wave trajectories, and calculating phase and amplitude anomalies along them. A time- or frequency -domain JWKB analysis yields local eigenfunctions, local dispersion relations, and conservation laws for the surface wave energy. The local dispersion relations determine the surface wave trajectories, and the energy equations determine the surface wave amplitudes. On an anisotrophic Earth model the local dispersion relation and the local vertical eigenfunctions depend explicitly on the direction of the local wavevector. Apart from the usual dynamical phase, which is the integral of the local wavevector along a raypath, there is an additional variation is phase. This additional phase, which is an analogue of the Berry phase in adiabatic quantum mechanics, vanishes in a waveguide with a local vertical two-fold symmetry axis or a local horizontal mirror plane. JWKB theory breaks down in the vicinity of caustics, where neighboring rays merge and the surface wave amplitude diverges. Based upon a potential representation of the surface wave field, a uniformly valid Maslov theory can be obtained. Surface wave trajectories are determined by a system of four ordinary differential equations which define a three-dimensional manifold in four-dimensional phase space (theta,phi,k_theta,k _phi), where theta is colatitude, phi is longitude, and k_theta and k _phi are the covariant components of the wavevector. There are no caustics in phase space; it is only when the rays in phase space are projected onto configuration space (theta,phi), the mixed spaces (k_theta,phi ) and (theta,k_phi), or onto momentum space (k_theta,k _phi), that caustics occur. The essential strategy is to employ a mixed or momentum space representation of the wavefield in the vicinity of a configuration space caustic.
Direct phase projection and transcranial focusing of ultrasound for brain therapy.
Pinton, Gianmarco F; Aubry, Jean-Francois; Tanter, Mickaël
2012-06-01
Ultrasound can be used to noninvasively treat the human brain with hyperthermia by focusing through the skull. To obtain an accurate focus, especially at high frequencies (>500 kHz), the phase of the transmitted wave must be modified to correct the aberrations introduced by the patient's individual skull morphology. Currently, three-dimensional finite-difference time-domain simulations are used to model a point source at the target. The outward-propagating wave crosses the measured representation of the human skull and is recorded at the therapy array transducer locations. The signal is then time reversed and experimentally transmitted back to its origin. These simulations are resource intensive and add a significant delay to treatment planning. Ray propagation is computationally efficient because it neglects diffraction and only describes two propagation parameters: the wave's direction and the phase. We propose a minimal method that is based only on the phase. The phase information is projected from the external skull surface to the array locations. This replaces computationally expensive finite-difference computations with an almost instantaneous direct phase projection calculation. For the five human skull samples considered, the phase distribution outside of the skull is shown to vary by less than λ/20 as it propagates over a 5 cm distance and the validity of phase projection is established over these propagation distances. The phase aberration introduced by the skull is characterized and is shown to have a good correspondence with skull morphology. The shape of this aberration is shown to have little variation with propagation distance. The focusing quality with the proposed phase-projection algorithm is shown to be indistinguishable from the gold-standard full finite-difference simulation. In conclusion, a spherical wave that is aberrated by the skull has a phase propagation that can be accurately described as radial, even after it has been distorted. By combining finite-difference simulations with a phase-projection algorithm, the time required for treatment planning is significantly reduced. The correlation length of the phase is used to validate the algorithm and it can also be used to provide guiding parameters for clinical array transducer design in terms of transducer spacing and phase error.
NASA Astrophysics Data System (ADS)
Yi, Faliu; Moon, Inkyu; Lee, Yeon H.
2015-01-01
Counting morphologically normal cells in human red blood cells (RBCs) is extremely beneficial in the health care field. We propose a three-dimensional (3-D) classification method of automatically determining the morphologically normal RBCs in the phase image of multiple human RBCs that are obtained by off-axis digital holographic microscopy (DHM). The RBC holograms are first recorded by DHM, and then the phase images of multiple RBCs are reconstructed by a computational numerical algorithm. To design the classifier, the three typical RBC shapes, which are stomatocyte, discocyte, and echinocyte, are used for training and testing. Nonmain or abnormal RBC shapes different from the three normal shapes are defined as the fourth category. Ten features, including projected surface area, average phase value, mean corpuscular hemoglobin, perimeter, mean corpuscular hemoglobin surface density, circularity, mean phase of center part, sphericity coefficient, elongation, and pallor, are extracted from each RBC after segmenting the reconstructed phase images by using a watershed transform algorithm. Moreover, four additional properties, such as projected surface area, perimeter, average phase value, and elongation, are measured from the inner part of each cell, which can give significant information beyond the previous 10 features for the separation of the RBC groups; these are verified in the experiment by the statistical method of Hotelling's T-square test. We also apply the principal component analysis algorithm to reduce the dimension number of variables and establish the Gaussian mixture densities using the projected data with the first eight principal components. Consequently, the Gaussian mixtures are used to design the discriminant functions based on Bayesian decision theory. To improve the performance of the Bayes classifier and the accuracy of estimation of its error rate, the leaving-one-out technique is applied. Experimental results show that the proposed method can yield good results for calculating the percentage of each typical normal RBC shape in a reconstructed phase image of multiple RBCs that will be favorable to the analysis of RBC-related diseases. In addition, we show that the discrimination performance for the counting of normal shapes of RBCs can be improved by using 3-D features of an RBC.
Optimized two-frequency phase-measuring-profilometry light-sensor temporal-noise sensitivity.
Li, Jielin; Hassebrook, Laurence G; Guan, Chun
2003-01-01
Temporal frame-to-frame noise in multipattern structured light projection can significantly corrupt depth measurement repeatability. We present a rigorous stochastic analysis of phase-measuring-profilometry temporal noise as a function of the pattern parameters and the reconstruction coefficients. The analysis is used to optimize the two-frequency phase measurement technique. In phase-measuring profilometry, a sequence of phase-shifted sine-wave patterns is projected onto a surface. In two-frequency phase measurement, two sets of pattern sequences are used. The first, low-frequency set establishes a nonambiguous depth estimate, and the second, high-frequency set is unwrapped, based on the low-frequency estimate, to obtain an accurate depth estimate. If the second frequency is too low, then depth error is caused directly by temporal noise in the phase measurement. If the second frequency is too high, temporal noise triggers ambiguous unwrapping, resulting in depth measurement error. We present a solution for finding the second frequency, where intensity noise variance is at its minimum.
NASA Technical Reports Server (NTRS)
Soffen, G. A.
1977-01-01
The Viking project launched two unmanned spacecraft to Mars in 1975 for scientific exploration with special emphasis on the search for life. Each spacecraft consisted of an orbiter and a lander. The landing sites were finally selected after the spacecraft were in orbit. Thirteen investigations were performed: three mapping experiments from the orbiter, one atmospheric investigation during the lander entry phase, eight experiments on the surface of the planet, and one using the spacecraft radio and radar systems. The experiments on the surface dealt principally with biology, chemistry, geology, and meteorology. Seventy-eight scientists have participated in the 13 teams performing these experiments. This paper is a summary of the project and an introduction to the articles that follow.
Wave Tank Studies of Phase Velocities of Short Wind Waves
NASA Astrophysics Data System (ADS)
Ermakov, S.; Sergievskaya, I.; Shchegolkov, Yu.
Wave tank studies of phase velocities of short wind waves have been carried out using Ka-band radar and an Optical Spectrum Analyser. The phase velocities were retrieved from measured radar and optical Doppler shifts, taking into account measurements of surface drift velocities. The dispersion relationship was studied in centimetre (cm)- and millimetre(mm)-scale wavelength ranges at different fetches and wind speeds, both for a clean water surface and for water covered with surfactant films. It is ob- tained that the phase velocities do not follow the dispersion relation of linear capillary- gravity waves, increasing with fetch and, therefore, depending on phase velocities of dominant decimetre (dm)-centimetre-scale wind waves. One thus can conclude that nonlinear cm-mm-scale harmonics bound to the dominant wind waves and propagat- ing with the phase velocities of the decimetric waves are present in the wind wave spectrum. The resulting phase velocities of short wind waves are determined by re- lation between free and bound waves. The relative intensity of the bound waves in the spectrum of short wind waves is estimated. It is shown that this relation depends strongly on the surfactant concentration, because the damping effect due to films is different for free and bound waves; this results to changes of phase velocities of wind waves in the presence of surfactant films. This work was supported by MOD, UK via DERA Winfrith (Project ISTC 1774P) and by RFBR (Project 02-05-65102).
Ultrasound beam transmission using a discretely orthogonal Gaussian aperture basis
NASA Astrophysics Data System (ADS)
Roberts, R. A.
2018-04-01
Work is reported on development of a computational model for ultrasound beam transmission at an arbitrary geometry transmission interface for generally anisotropic materials. The work addresses problems encountered when the fundamental assumptions of ray theory do not hold, thereby introducing errors into ray-theory-based transmission models. Specifically, problems occur when the asymptotic integral analysis underlying ray theory encounters multiple stationary phase points in close proximity, due to focusing caused by concavity on either the entry surface or a material slowness surface. The approach presented here projects integrands over both the transducer aperture and the entry surface beam footprint onto a Gaussian-derived basis set, thereby distributing the integral over a summation of second-order phase integrals which are amenable to single stationary phase point analysis. Significantly, convergence is assured provided a sufficiently fine distribution of basis functions is used.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dorhout, Jacquelyn Marie
2017-11-21
The goal of this project is to determine whether variables such as the molarity of nitric acid (HNO 3), temperature, and surface characteristics of uranium materials have an effect on the fractionation of 15N between the solution and vapor phases.
NASA Astrophysics Data System (ADS)
Argaman, E.; Egozi, R.; Goldshlager, N.
2012-04-01
Water availability in arid regions is a major limiting factor, which affect plant development. Therefore, knowledge about preliminary and ongoing spatial & temporal conditions (e.g. land surface properties, hydrological regime and vegetation dynamics) can improve greatly afforestation practice. The Ambassadors forest is one of the Jewish National Fund (JNF) new afforestation projects (initiated on 2005), which rely on water harvesting irrigation systems, located at the northern Negev region, Israel. Temporal and spatial processes are studied utilizing ground, air-borne and space-borne techniques for assessment of surface processes, that take place due to significant land-use change. Since 2005 the area shows significant variation of surface energy balance components which impact the spatial and temporal forest generation. Both human and climate affect these parameters, hence their influence is essential for future study of the region. Parameters of surface Albedo & Temperature and Vegetation dynamics are gathered by space-borne sensors (e.g. MODIS, Landsat & ALI) and verified at field scale in conjunction with ground-truth measurements of climate and soil properties. In addition, the project study various scenarios that might result from diverse climate trajectories that impact soil formation factors and therefore forest development. Preliminary results show that surface physical & ecoligical properties had changed significantly since the aforestation project began, comparing previous years. Sharp increase of surface albedo detected since 2005 that raised from 0.25 to 0.32, while vegetation density, estimated from NDVI, had dropped from annaul average of 0.21 down to 0.13 during 10-year time period. These changes are related to human interferance. The current paper presents the first phase of the long-term study of the Remote Sensing analysis and the current surface monitoring phase.
Temperature Changes in the United States. Chapter 6
NASA Technical Reports Server (NTRS)
Vose, R. S.; Easterling, D. R.; Kunkel, K. E.; LeGrande, A. N.; Wehner, M. F.
2017-01-01
Temperature is among the most important climatic elements used in decision-making. For example, builders and insurers use temperature data for planning and risk management while energy companies and regulators use temperature data to predict demand and set utility rates. Temperature is also a key indicator of climate change: recent increases are apparent over the land, ocean, and troposphere, and substantial changes are expected for this century. This chapter summarizes the major observed and projected changes in near-surface air temperature over the United States, emphasizing new data sets and model projections since the Third National Climate Assessment (NCA3). Changes are depicted using a spectrum of observations, including surface weather stations, moored ocean buoys, polar-orbiting satellites, and temperature-sensitive proxies. Projections are based on global models and downscaled products from CMIP5 (Coupled Model Intercomparison Project Phase 5) using a suite of Representative Concentration Pathways (RCPs; see Ch. 4: Projections for more on RCPs and future scenarios).
Recommended Practices to Improve Nurse Tank Safety: Phase II
DOT National Transportation Integrated Search
2013-12-01
This project addressed four topics: Pinhole leaks in nurse tanks were studied by radiography, serial milling, and side-angle ultrasound. These measurements indicated that welding surfaces contaminated by water, mill scale, rust, or other contamin...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mani, Amir; Tsai, Frank T. -C.; Kao, Shih-Chieh
Our study introduces a mixed integer linear fractional programming (MILFP) method to optimize conjunctive use of future surface water and groundwater resources under projected climate change scenarios. The conjunctive management model maximizes the ratio of groundwater usage to reservoir water usage. Future inflows to the reservoirs were estimated from the future runoffs projected through hydroclimate modeling considering the Variable Infiltration Capacity model, and 11 sets of downscaled Coupled Model Intercomparison Project phase 5 global climate model projections. Bayesian model averaging was adopted to quantify uncertainty in future runoff projections and reservoir inflow projections due to uncertain future climate projections. Optimizedmore » conjunctive management solutions were investigated for a water supply network in northern Louisiana which includes the Sparta aquifer. Runoff projections under climate change scenarios indicate that runoff will likely decrease in winter and increase in other seasons. Ultimately, results from the developed conjunctive management model with MILFP indicate that the future reservoir water, even at 2.5% low inflow cumulative probability level, could counterbalance groundwater pumping reduction to satisfy demands while improving the Sparta aquifer through conditional groundwater head constraint.« less
Mani, Amir; Tsai, Frank T. -C.; Kao, Shih-Chieh; ...
2016-06-16
Our study introduces a mixed integer linear fractional programming (MILFP) method to optimize conjunctive use of future surface water and groundwater resources under projected climate change scenarios. The conjunctive management model maximizes the ratio of groundwater usage to reservoir water usage. Future inflows to the reservoirs were estimated from the future runoffs projected through hydroclimate modeling considering the Variable Infiltration Capacity model, and 11 sets of downscaled Coupled Model Intercomparison Project phase 5 global climate model projections. Bayesian model averaging was adopted to quantify uncertainty in future runoff projections and reservoir inflow projections due to uncertain future climate projections. Optimizedmore » conjunctive management solutions were investigated for a water supply network in northern Louisiana which includes the Sparta aquifer. Runoff projections under climate change scenarios indicate that runoff will likely decrease in winter and increase in other seasons. Ultimately, results from the developed conjunctive management model with MILFP indicate that the future reservoir water, even at 2.5% low inflow cumulative probability level, could counterbalance groundwater pumping reduction to satisfy demands while improving the Sparta aquifer through conditional groundwater head constraint.« less
Antibody enhancement of free-flow electrophoresis
NASA Technical Reports Server (NTRS)
Cohly, H. H. P.; Morrison, Dennis R.; Atassi, M. Zouhair
1988-01-01
Specific T cell clones and antibodies (ABs) were developed to study the efficiency of purifying closely associated T cells using Continuous Flow Electrophoresis System. Enhanced separation is accomplished by tagging cells first with ABs directed against the antigenic determinants on the cell surface and then with ABs against the Fc portion of the first AB. This second AB protrudes sufficiently beyond the cell membrane and glycocalyx to become the major overall cell surface potential determinant and thus causes a reduction of electrophoretic mobility. This project was divided into three phases. Phase one included development of specific T cell clones and separation of these specific clones. Phase two extends these principles to the separation of T cells from spleen cells and immunized lymph node cells. Phase three applies this double antibody technique to the separation of T cytotoxic cells from bone marrow.
The global gridded crop model intercomparison: Data and modeling protocols for Phase 1 (v1.0)
Elliott, J.; Müller, C.; Deryng, D.; ...
2015-02-11
We present protocols and input data for Phase 1 of the Global Gridded Crop Model Intercomparison, a project of the Agricultural Model Intercomparison and Improvement Project (AgMIP). The project consist of global simulations of yields, phenologies, and many land-surface fluxes using 12–15 modeling groups for many crops, climate forcing data sets, and scenarios over the historical period from 1948 to 2012. The primary outcomes of the project include (1) a detailed comparison of the major differences and similarities among global models commonly used for large-scale climate impact assessment, (2) an evaluation of model and ensemble hindcasting skill, (3) quantification ofmore » key uncertainties from climate input data, model choice, and other sources, and (4) a multi-model analysis of the agricultural impacts of large-scale climate extremes from the historical record.« less
NASA Technical Reports Server (NTRS)
Koster, Randal D.; Fekete, Balazs M.; Huffman, George J.; Stackhouse, Paul W.
2006-01-01
The International Satellite Land Surface Climatology Project Initiative 2 (ISLSCP-2) data set provides the data needed to characterize the surface water budget across much of the globe in terms of energy availability (net radiation) and water availability (precipitation) controls. The data, on average, are shown to be consistent with Budyko s decades-old framework, thereby demonstrating the continuing relevance of Budyko s semiempirical relationships. This consistency, however, appears only when a small subset of the data with hydrologically suspicious behavior is removed from the analysis. In general, the precipitation, net radiation, and runoff data also appear consistent in their interannual variability and in the phasing of their seasonal cycles.
NASA Astrophysics Data System (ADS)
Ben, R.; Chalaturnyk, R.; Gardner, C.; Hawkes, C.; Johnson, J.; White, D.; Whittaker, S.
2008-12-01
In July 2000, a major research project was initiated to study the geological storage of CO2 as part of a 5000 tonnes/day EOR project planned for the Weyburn Field in Saskatchewan, Canada. Major objectives of the IEA GHG Weyburn CO2 monitoring and storage project included: assessing the integrity of the geosphere encompassing the Weyburn oil pool for effective long-term storage of CO2; monitoring the movement of the injected CO2, and assessing the risk of migration of CO2 from the injection zone (approximately 1500 metres depth) to the surface. Over the period 2000-2004, a diverse group of 80+ researchers worked on: geological, geophysical, and hydrogeological characterizations at both the regional (100 km beyond the field) and detailed scale (10 km around the field); conducted time-lapse geophysical surveys; carried out surface and subsurface geochemical surveys; and undertook numerical reservoir simulations. Results of the characterization were used for a performance assessment that concluded the risk of CO2 movement to the biosphere was very small. By September 2007, more than 14 Mtonnes of CO2 had been injected into the Weyburn reservoir, including approximately 3 Mtonnes recycled from oil production. A "Final Phase" research project was initiated (2007- 2011) to contribute to a "Best Practices" guide for long-term CO2 storage in EOR settings. Research objectives include: improving the geoscience characterization; further detailed analysis and data collection on the role of wellbores; additional geochemical and geophysical monitoring activities; and an emphasis on quantitative risk assessments using multiple analysis techniques. In this talk a review of results from Phase I will be presented followed by plans and initial results for the Final Phase.
High Power RF Testing of A 3-Cell Superconducting Traveling Wave Accelerating Structure
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kanareykin, Alex; Kostin, Romna; Avrakhov, Pavel
Euclid Techlabs has completed the Phase II SBIR project, entitled “High Power RF Testing of a 3-Cell Superconducting Traveling Wave Accelerating Structure” under Grant #DE-SC0006300. In this final technical report, we summarize the major achievements of Phase I of the project and review the details of Phase II of the project. The accelerating gradient in a superconducting structure is limited mainly by quenching, i.e., by the maximum surface RF magnetic field. Various techniques have been developed to increase the gradient. A traveling wave accelerating SC structure with a feedback waveguide was suggested to allow an increased transit time factor andmore » ultimately, a maximum gradient that is 22%-24% higher than in the best of the time standing wave SRF cavity solution. The proposed structure has an additional benefit in that it can be fabricated much longer than the standing wave ones that are limited by the field flatness factor. Taken together, all of these factors will result in a significant overall length and, correspondingly cost reduction of the SRF based linear collider ILC or SRF technology based FELs. In Phase I of this project, a 3-cell L-band SC traveling wave cavity was designed. Cavity shape, surface field ratios, inter-cell coupling coefficients, accelerating field flatness have been reviewed with the analysis of tuning issues. Moreover, the technological aspects of SC traveling wave accelerating structure fabrication have been studied. As the next step in the project, the Phase II experimental program included engineering design, manufacturing, surface processing and high gradient testing. Euclid Techlabs, LLC contracted AES, Inc. to manufacture two niobium cavities. Euclid Techlabs cold tested traveling wave regime in the cavity, and the results showed very good agreement with mathematical model specially developed for superconducting traveling wave cavity performance analysis. Traveling wave regime was adjusted by amplitude and phase variation of input signals due to application of developed power feeding scheme. Traveling wave excitation, adjustment and detection were successfully tested. Auxiliary equipment required for high power test such as the tuner, power and measure couplers, holding plates for VTS at Fermilab were developed and successfully tested. Both TW SRF cavities were fabricated by AES, Inc. without stiffening ribs before this company closed their production facility. Currently Roark EB welding company is finishing now welding process of the cavity for the high power testing at Fermilab VTS. Successful demonstration of high gradients in the 3-cell cavity along with studies of traveling wave excitation and tuning issues is leading to successful development of superconducting traveling wave technology for ILC applications and other future high energy SC accelerators.« less
Background Oriented Schlieren Implementation in a Jet-Surface Interaction Test
NASA Technical Reports Server (NTRS)
Clem, Michelle M.; Brown, Clifford A.; Fagan, Amy
2013-01-01
Many current and future aircraft designs rely on the wing or other aircraft surfaces to shield the engine noise from observers on the ground. However the available data regarding how a planar surface interacts with a jet to shield and/or enhance the jet noise are currently limited. Therefore, the Jet-Surface Interaction Tests supported by NASA's Fundamental Aeronautics Program's Fixed Wing Project were undertaken to supply experimental data covering a wide range of surface geometries and positions interacting with high-speed jet flows in order to support the development of noise prediction methods. Phase 1 of the Test was conducted in the Aero-Acoustic Propulsion Laboratory at NASA Glenn Research Center and consisted of validating noise prediction schemes for a round nozzle interacting with a planar surface. Phased array data and far-field acoustic data were collected for both the shielded and reflected sides of the surface. Phase 1 results showed that the broadband shock noise was greatly reduced by the surface when the jet was operated at the over-expanded condition, however, it was unclear whether this reduction was due a change in the shock cell structure by the surface. In the present study, Background Oriented Schlieren is implemented in Phase 2 of the Jet-Surface Interaction Tests to investigate whether the planar surface interacts with the high-speed jet ow to change the shock cell structure. Background Oriented Schlieren data are acquired for under-expanded, ideally-expanded, and over-expanded ow regimes for multiple axial and radial positions of the surface at three different plate lengths. These data are analyzed with far-field noise measurements to relate the shock cell structure to the broadband shock noise produced by a jet near a surface.
NASA Astrophysics Data System (ADS)
Madrigal, Carlos A.; Restrepo, Alejandro; Branch, John W.
2016-09-01
3D reconstruction of small objects is used in applications of surface analysis, forensic analysis and tissue reconstruction in medicine. In this paper, we propose a strategy for the 3D reconstruction of small objects and the identification of some superficial defects. We applied a technique of projection of structured light patterns, specifically sinusoidal fringes and an algorithm of phase unwrapping. A CMOS camera was used to capture images and a DLP digital light projector for synchronous projection of the sinusoidal pattern onto the objects. We implemented a technique based on a 2D flat pattern as calibration process, so the intrinsic and extrinsic parameters of the camera and the DLP were defined. Experimental tests were performed in samples of artificial teeth, coal particles, welding defects and surfaces tested with Vickers indentation. Areas less than 5cm were studied. The objects were reconstructed in 3D with densities of about one million points per sample. In addition, the steps of 3D description, identification of primitive, training and classification were implemented to recognize defects, such as: holes, cracks, roughness textures and bumps. We found that pattern recognition strategies are useful, when quality supervision of surfaces has enough quantities of points to evaluate the defective region, because the identification of defects in small objects is a demanding activity of the visual inspection.
Early 20th-century Arctic warming intensified by Pacific and Atlantic multidecadal variability
NASA Astrophysics Data System (ADS)
Tokinaga, Hiroki; Xie, Shang-Ping; Mukougawa, Hitoshi
2017-06-01
With amplified warming and record sea ice loss, the Arctic is the canary of global warming. The historical Arctic warming is poorly understood, limiting our confidence in model projections. Specifically, Arctic surface air temperature increased rapidly over the early 20th century, at rates comparable to those of recent decades despite much weaker greenhouse gas forcing. Here, we show that the concurrent phase shift of Pacific and Atlantic interdecadal variability modes is the major driver for the rapid early 20th-century Arctic warming. Atmospheric model simulations successfully reproduce the early Arctic warming when the interdecadal variability of sea surface temperature (SST) is properly prescribed. The early 20th-century Arctic warming is associated with positive SST anomalies over the tropical and North Atlantic and a Pacific SST pattern reminiscent of the positive phase of the Pacific decadal oscillation. Atmospheric circulation changes are important for the early 20th-century Arctic warming. The equatorial Pacific warming deepens the Aleutian low, advecting warm air into the North American Arctic. The extratropical North Atlantic and North Pacific SST warming strengthens surface westerly winds over northern Eurasia, intensifying the warming there. Coupled ocean-atmosphere simulations support the constructive intensification of Arctic warming by a concurrent, negative-to-positive phase shift of the Pacific and Atlantic interdecadal modes. Our results aid attributing the historical Arctic warming and thereby constrain the amplified warming projected for this important region.
NASA Technical Reports Server (NTRS)
Van Den Hurk, Bart; Kim, Hyungjun; Krinner, Gerhard; Seneviratne, Sonia I.; Derksen, Chris; Oki, Taikan; Douville, Herve; Colin, Jeanne; Ducharne, Agnes; Cheruy, Frederique;
2016-01-01
The Land Surface, Snow and Soil Moisture Model Intercomparison Project (LS3MIP) is designed to provide a comprehensive assessment of land surface, snow, and soil moisture feedbacks on climate variability and climate change, and to diagnose systematic biases in the land modules of current Earth System Models (ESMs). The solid and liquid water stored at the land surface has a large influence on the regional climate, its variability and predictability, including effects on the energy, water and carbon cycles. Notably, snow and soil moisture affect surface radiation and flux partitioning properties, moisture storage and land surface memory. They both strongly affect atmospheric conditions, in particular surface air temperature and precipitation, but also large-scale circulation patterns. However, models show divergent responses and representations of these feedbacks as well as systematic biases in the underlying processes. LS3MIP will provide the means to quantify the associated uncertainties and better constrain climate change projections, which is of particular interest for highly vulnerable regions (densely populated areas, agricultural regions, the Arctic, semi-arid and other sensitive terrestrial ecosystems).The experiments are subdivided in two components, the first addressing systematic land biases in offline mode (LMIP, building upon the 3rd phase of Global Soil Wetness Project; GSWP3) and the second addressing land feedbacks attributed to soil moisture and snow in an integrated framework (LFMIP, building upon the GLACE-CMIP blueprint).
van den Hurk, Bart; Kim, Hyungjun; Krinner, Gerhard; ...
2016-08-24
The Land Surface, Snow and Soil Moisture Model Intercomparison Project (LS3MIP) is designed to provide a comprehensive assessment of land surface, snow and soil moisture feedbacks on climate variability and climate change, and to diagnose systematic biases in the land modules of current Earth system models (ESMs). Furthermore, the solid and liquid water stored at the land surface has a large influence on the regional climate, its variability and predictability, including effects on the energy, water and carbon cycles. Notably, snow and soil moisture affect surface radiation and flux partitioning properties, moisture storage and land surface memory. They both stronglymore » affect atmospheric conditions, in particular surface air temperature and precipitation, but also large-scale circulation patterns. But, models show divergent responses and representations of these feedbacks as well as systematic biases in the underlying processes. LS3MIP will provide the means to quantify the associated uncertainties and better constrain climate change projections, which is of particular interest for highly vulnerable regions (densely populated areas, agricultural regions, the Arctic, semi-arid and other sensitive terrestrial ecosystems). The experiments are subdivided in two components, the first addressing systematic land biases in offline mode (“LMIP”, building upon the 3rd phase of Global Soil Wetness Project; GSWP3) and the second addressing land feedbacks attributed to soil moisture and snow in an integrated framework (“LFMIP”, building upon the GLACE-CMIP blueprint).« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
van den Hurk, Bart; Kim, Hyungjun; Krinner, Gerhard
The Land Surface, Snow and Soil Moisture Model Intercomparison Project (LS3MIP) is designed to provide a comprehensive assessment of land surface, snow and soil moisture feedbacks on climate variability and climate change, and to diagnose systematic biases in the land modules of current Earth system models (ESMs). Furthermore, the solid and liquid water stored at the land surface has a large influence on the regional climate, its variability and predictability, including effects on the energy, water and carbon cycles. Notably, snow and soil moisture affect surface radiation and flux partitioning properties, moisture storage and land surface memory. They both stronglymore » affect atmospheric conditions, in particular surface air temperature and precipitation, but also large-scale circulation patterns. But, models show divergent responses and representations of these feedbacks as well as systematic biases in the underlying processes. LS3MIP will provide the means to quantify the associated uncertainties and better constrain climate change projections, which is of particular interest for highly vulnerable regions (densely populated areas, agricultural regions, the Arctic, semi-arid and other sensitive terrestrial ecosystems). The experiments are subdivided in two components, the first addressing systematic land biases in offline mode (“LMIP”, building upon the 3rd phase of Global Soil Wetness Project; GSWP3) and the second addressing land feedbacks attributed to soil moisture and snow in an integrated framework (“LFMIP”, building upon the GLACE-CMIP blueprint).« less
NASA Technical Reports Server (NTRS)
Rossow, William B. (Principal Investigator)
Since 1983 an international group of institutions has collected and analyzed satellite radiance measurements from up to five geostationary and two polar orbiting satellites to infer the global distribution of cloud properties and their diurnal, seasonal and interannual variations. The primary focus of the first phase of the project (1983-1995) was the elucidation of the role of clouds in the radiation budget (top of the atmosphere and surface). In the second phase of the project (1995 onwards) the analysis also concerns improving understanding of clouds in the global hydrological cycle. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1983-07-01; Stop_Date=] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=112 Km; Longitude_Resolution=112 Km; Temporal_Resolution=5-day].
NASA Astrophysics Data System (ADS)
Kminek, Gerhard; Vago, Jorge; Gianfiglio, Giacinto; Haldemann, Albert; Elfving, Anders; Pinel, Jacques; McCoy, Don
The ExoMars mission will deploy two science elements on the Martian surface: a rover and a small, fixed package. The fixed Humboldt science package, will measure planetary geophysics parameters important for understanding Mars's evolution and habitability, identify possible surface hazards to future human missions, and study the environment. The Rover Pasteur science package will search for signs of past and present life on Mars, and characterise the water and geochemical environment with depth by collecting and analysing subsurface samples down to 2 meters. The very powerful combination of surface mobility and subsurface access to locations where organic molecules may be well-preserved is unique to this mission. ExoMars is currently in Phase B prior to PDR. This presentation will provide an update on the project status, including instrument and technology developments.
High-precision real-time 3D shape measurement based on a quad-camera system
NASA Astrophysics Data System (ADS)
Tao, Tianyang; Chen, Qian; Feng, Shijie; Hu, Yan; Zhang, Minliang; Zuo, Chao
2018-01-01
Phase-shifting profilometry (PSP) based 3D shape measurement is well established in various applications due to its high accuracy, simple implementation, and robustness to environmental illumination and surface texture. In PSP, higher depth resolution generally requires higher fringe density of projected patterns which, in turn, lead to severe phase ambiguities that must be solved with additional information from phase coding and/or geometric constraints. However, in order to guarantee the reliability of phase unwrapping, available techniques are usually accompanied by increased number of patterns, reduced amplitude of fringe, and complicated post-processing algorithms. In this work, we demonstrate that by using a quad-camera multi-view fringe projection system and carefully arranging the relative spatial positions between the cameras and the projector, it becomes possible to completely eliminate the phase ambiguities in conventional three-step PSP patterns with high-fringe-density without projecting any additional patterns or embedding any auxiliary signals. Benefiting from the position-optimized quad-camera system, stereo phase unwrapping can be efficiently and reliably performed by flexible phase consistency checks. Besides, redundant information of multiple phase consistency checks is fully used through a weighted phase difference scheme to further enhance the reliability of phase unwrapping. This paper explains the 3D measurement principle and the basic design of quad-camera system, and finally demonstrates that in a large measurement volume of 200 mm × 200 mm × 400 mm, the resultant dynamic 3D sensing system can realize real-time 3D reconstruction at 60 frames per second with a depth precision of 50 μm.
NASA Technical Reports Server (NTRS)
Kennedy, Kriss J.
2009-01-01
The Surface Habitat Systems (SHS) Focused Investment Group (FIG) is part of the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) effort to provide a focused direction and funding to the various projects that are working on human surface habitat designs and technologies for the planetary exploration missions. The overall SHS-FIG effort focuses on directing and guiding those projects that: 1) develop and demonstrate new surface habitat system concepts, innovations, and technologies to support human exploration missions, 2) improve environmental systems that interact with human habitats, 3) handle and emplace human surface habitats, and 4) focus on supporting humans living and working in habitats on planetary surfaces. The activity areas of the SHS FIG described herein are focused on the surface habitat project near-term objectives as described in this document. The SHS-FIG effort focuses on mitigating surface habitat risks (as identified by the Lunar Surface Systems Project Office (LSSPO) Surface Habitat Element Team; and concentrates on developing surface habitat technologies as identified in the FY08 gap analysis. The surface habitat gap assessment will be updated annually as the surface architecture and surface habitat definition continues to mature. These technologies are mapped to the SHS-FIG Strategic Development Roadmap. The Roadmap will bring to light the areas where additional innovative efforts are needed to support the development of habitat concepts and designs and the development of new technologies to support of the LSSPO Habitation Element development plan. Three specific areas of development that address Lunar Architecture Team (LAT)-2 and Constellation Architecture Team (CxAT) Lunar habitat design issues or risks will be focused on by the SHS-FIG. The SHS-FIG will establish four areas of development that will help the projects prepare in their planning for surface habitat systems development. Those development areas are the 1) surface habitat concept definition, 2) inflatable surface habitat development, and 3) autonomous habitat operations, and 4) cross-cutting / systems engineering. In subsequent years, the SHS-FIG will solicit a call for innovations and technologies that will support the development of these four development areas. The other development areas will be assessed yearly and identified on the SHS-FIG s Strategic Development Roadmap. Initial investment projects that are funded by the Constellation Program Office (CxPO), LSSPO, or the Exploration Technology Development Projects (ETDP) will also be included on the Roadmap. For example, in one or two years from now, the autonomous habitat operations and testbed would collaborations with the Integrated Systems Health Management (ISHM) and Automation for Operations ETDP projects, which will give the surface habitat projects an integrated habitat autonomy testbed to test software and systems. The SHS-FIG scope is to provide focused direction for multiple innovations, technologies and subsystems that are needed to support humans at a remote planetary surface habitat during the concept development, design definition, and integration phases of that project. Subsystems include: habitability, lightweight structures, power management, communications, autonomy, deployment, outfitting, life support, wireless connectivity, lighting, thermal and more.
DOT National Transportation Integrated Search
2017-09-01
Over time, many Louisiana highway embankments have experienced surface sliding failures, a safety issue causing traffic disruptions. Since no advance-warning system is available for these highway embankment failures, the Louisiana Department of Trans...
Injection molding lens metrology using software configurable optical test system
NASA Astrophysics Data System (ADS)
Zhan, Cheng; Cheng, Dewen; Wang, Shanshan; Wang, Yongtian
2016-10-01
Optical plastic lens produced by injection molding machine possesses numerous advantages of light quality, impact resistance, low cost, etc. The measuring methods in the optical shop are mainly interferometry, profile meter. However, these instruments are not only expensive, but also difficult to alignment. The software configurable optical test system (SCOTS) is based on the geometry of the fringe refection and phase measuring deflectometry method (PMD), which can be used to measure large diameter mirror, aspheric and freeform surface rapidly, robustly, and accurately. In addition to the conventional phase shifting method, we propose another data collection method called as dots matrix projection. We also use the Zernike polynomials to correct the camera distortion. This polynomials fitting mapping distortion method has not only simple operation, but also high conversion precision. We simulate this test system to measure the concave surface using CODE V and MATLAB. The simulation results show that the dots matrix projection method has high accuracy and SCOTS has important significance for on-line detection in optical shop.
The Southern Ocean in the Coupled Model Intercomparison Project phase 5
Meijers, A. J. S.
2014-01-01
The Southern Ocean is an important part of the global climate system, but its complex coupled nature makes both its present state and its response to projected future climate forcing difficult to model. Clear trends in wind, sea-ice extent and ocean properties emerged from multi-model intercomparison in the Coupled Model Intercomparison Project phase 3 (CMIP3). Here, we review recent analyses of the historical and projected wind, sea ice, circulation and bulk properties of the Southern Ocean in the updated Coupled Model Intercomparison Project phase 5 (CMIP5) ensemble. Improvements to the models include higher resolutions, more complex and better-tuned parametrizations of ocean mixing, and improved biogeochemical cycles and atmospheric chemistry. CMIP5 largely reproduces the findings of CMIP3, but with smaller inter-model spreads and biases. By the end of the twenty-first century, mid-latitude wind stresses increase and shift polewards. All water masses warm, and intermediate waters freshen, while bottom waters increase in salinity. Surface mixed layers shallow, warm and freshen, whereas sea ice decreases. The upper overturning circulation intensifies, whereas bottom water formation is reduced. Significant disagreement exists between models for the response of the Antarctic Circumpolar Current strength, for reasons that are as yet unclear. PMID:24891395
Texas Intense Positron Source (TIPS)
NASA Astrophysics Data System (ADS)
O'Kelly, D.
2003-03-01
The Texas Intense Positron Source (TIPS) is a state of the art variable energy positron beam under construction at the Nuclear Engineering Teaching Laboratory (NETL). Projected intensities on the order of the order of 10^7 e+/second using ^64Cu as the positron source are expected. Owing to is short half-life (t1/2 12.8 hrs), plans are to produce the ^64Cu isotope on-site using beam port 1 of NETL TRIGA Mark II reactor. Following tungsten moderation, the positrons will be electrostatically focused and accelerated from few 10's of eV up to 30 keV. This intensity and energy range should allow routine performance of several analytical techniques of interest to surface scientists (PALS, PADB and perhaps PAES and LEPD.) The TIPS project is being developed in parallel phases. Phase I of the project entails construction of the vacuum system, source chamber, main beam line, electrostatic/magnetic focusing and transport system as well as moderator design. Initial construction, testing and characterization of moderator and beam transport elements are underway and will use a commercially available 10 mCi ^22Na radioisotope as a source of positrons. Phase II of the project is concerned primarily with the Cu source geometry and thermal properties as well as production and physical handling of the radioisotope. Additional instrument optimizing based upon experience gained during Phase I will be incorporated in the final design. Current progress of both phases will be presented along with motivations and future directions.
Changes in groundwater recharge under projected climate in the upper Colorado River basin
Tillman, Fred; Gangopadhyay, Subhrendu; Pruitt, Tom
2016-01-01
Understanding groundwater-budget components, particularly groundwater recharge, is important to sustainably manage both groundwater and surface water supplies in the Colorado River basin now and in the future. This study quantifies projected changes in upper Colorado River basin (UCRB) groundwater recharge from recent historical (1950–2015) through future (2016–2099) time periods, using a distributed-parameter groundwater recharge model with downscaled climate data from 97 Coupled Model Intercomparison Project Phase 5 climate projections. Simulated future groundwater recharge in the UCRB is generally expected to be greater than the historical average in most decades. Increases in groundwater recharge in the UCRB are a consequence of projected increases in precipitation, offsetting reductions in recharge that would result from projected increased temperatures.
Li, Jing; Li, Fadong; Liu, Qiang
2017-07-01
Large-scale irrigation projects have impacted the regional surface-groundwater interactions in the North China Plain (NCP). Given this concern, the aim of this study is to evaluate levels of PAH pollution, identify the sources of the PAHs, analyze the influence of surface-groundwater interactions on PAH distribution, and propose urgent management strategies for PAHs in China's agricultural areas. PAH concentrations, hydrochemical indicators and stable isotopic compositions (δ 18 O and δ 2 H) were determined for surface water (SW) and groundwater (GW) samples. PAHs concentrations in surface water and groundwater varied from 11.84 to 393.12 ng/L and 8.51-402.84 ng/L, respectively, indicating mild pollution. The seasonal variations showed the following trend: PAHs in surface water at the low-water phase > PAHs in groundwater at the low-water phase > PAHs in surface water at the high-water phase > PAHs in groundwater at the high-water phase. Hydrochemical and δ 18 O value of most groundwater samples distributed between the Yellow River and seawater. The mean value of mixture ratio of the Yellow River water recharge to the groundwater was 65%, few anomalous sites can reach to 90%. Surface-groundwater interactions influence the spatial distribution of PAHs in the study area. In light of the ongoing serious pollution, management practices for source control, improved control technologies, and the construction of a monitoring network to warn of increased risk are urgently needed. Copyright © 2017 Elsevier Ltd. All rights reserved.
Surface based factory for the production of life support and technology support products
NASA Technical Reports Server (NTRS)
1987-01-01
The presence of a manned space colony on Mars may be expected to involve three phases in the utilization of planetary resources: (1) survival phase in which air, water, and food are produced, (2) self sufficiency phase in which chemicals, fuels, pharmaceuticals, polymers, and metals are produced, and (3) export to earth of materials and technology 1 phase in which the unique advantage of the extraterrestrial environment is fully exploited. The Advanced Design Project is administered as an interdisciplinary effort involving students and faculty throughout the College of Engineering. Senior students from Chemical, Civil, Electrical, and Mechanical Engineering are participating as a team. Multi discipline interfacing and coordination are stressed throughout the project. An interdisciplinary senior design course was developed and offered in the Spring of 1987. The first task of the survival phase is that of providing a supply of water and air adequate to support a ten person colony. The project has been divided into three subgroups: (1) design of a manufacturing and storage facility for air, (2) search and drill for water or water-bearing materials, and (3) retrieve, purify, and store potable water. The conceptual design phase has been completed and the project is being documented. The second task of the survival phase is that of providing a replenish able food supply. This task has two requirements: producing a supply of protein and providing an environment for growing plants for food. For the first requirement, we considered the design of a bioreactor system capable of growing beef cells for protein production. For the second, a design must be developed for a manufacturing system to produce materials needed to build a greenhouse farm.
NASA Astrophysics Data System (ADS)
Zawadowicz, M. A.; Cziczo, D. J.
2013-12-01
Atmospheric aerosol particles can be composed of inorganic salts, such as ammonium sulfate and sodium chloride, and therefore exhibit hygroscopic properties. Many inorganic salts have very well-defined deliquescence and efflorescence points at which they take up and lose water, respectively. For example, the deliquescence relative humidity of pure ammonium sulfate is about 80% and its efflorescence point is about 35%. This behavior of ammonium sulfate is important to atmospheric chemistry because some reactions, such as the hydrolysis of nitrogen pentoxide, occur on aqueous but not crystalline surfaces. Deliquescence and efflorescence of simple inorganic salt particles have been investigated by a variety of methods, such as IR spectroscopy, tandem mobility analysis and electrodynamic balance. Field measurements have shown that atmospheric aerosol are not typically a single inorganic salt, instead they often contain organic as well as inorganic species. Mixed inorganic/organic aerosol particles, while abundant in the atmosphere, have not been studied as extensively. Many recent studies have focused on microscopy techniques that require deposition of the aerosol on a glass slide, possibly changing its surface properties. This project investigates the deliquescence and efflorescence points, phase separation and ability to exchange gas-phase components of mixed organic and inorganic aerosol using a flow tube coupled with FTIR spectroscopy. Ammonium sulfate aerosol mixed with organic polyols with different O:C ratios, including glycerol, 1,2,6-hexanetriol, 1,4-butanediol and 1,5-pentanediol have been investigated. This project aims to study gas-phase exchange in these aerosol systems to determine if exchange is impacted when phase separation occurs.
Temporal phase unwrapping algorithms for fringe projection profilometry: A comparative review
Zuo, Chao; Huang, Lei; Zhang, Minliang; ...
2016-05-06
In fringe projection pro lometry (FPP), temporal phase unwrapping is an essential procedure to recover an unambiguous absolute phase even in the presence of large discontinuities or spatially isolated surfaces. So far, there are typically three groups of temporal phase unwrapping algorithms proposed in the literature: multi-frequency (hierarchical) approach, multi-wavelength (heterodyne) approach, and number-theoretical approach. In this paper, the three methods are investigated and compared in details by analytical, numerical, and experimental means. The basic principles and recent developments of the three kind of algorithms are firstly reviewed. Then, the reliability of different phase unwrapping algorithms is compared based onmore » a rigorous stochastic noise model. Moreover, this noise model is used to predict the optimum fringe period for each unwrapping approach, which is a key factor governing the phase measurement accuracy in FPP. Simulations and experimental results verified the correctness and validity of the proposed noise model as well as the prediction scheme. The results show that the multi-frequency temporal phase unwrapping provides the best unwrapping reliability, while the multi-wavelength approach is the most susceptible to noise-induced unwrapping errors.« less
Prediction of forces and moments for hypersonic flight vehicle control effectors
NASA Technical Reports Server (NTRS)
Maughmer, Mark D.; Long, Lyle N.; Guilmette, Neal; Pagano, Peter
1993-01-01
This research project includes three distinct phases. For completeness, all three phases of the work are briefly described in this report. The goal was to develop methods of predicting flight control forces and moments for hypersonic vehicles which could be used in a preliminary design environment. The first phase included a preliminary assessment of subsonic/supersonic panel methods and hypersonic local flow inclination methods for such predictions. While these findings clearly indicated the usefulness of such methods for conceptual design activities, deficiencies exist in some areas. Thus, a second phase of research was conducted in which a better understanding was sought for the reasons behind the successes and failures of the methods considered, particularly for the cases at hypersonic Mach numbers. This second phase involved using computational fluid dynamics methods to examine the flow fields in detail. Through these detailed predictions, the deficiencies in the simple surface inclination methods were determined. In the third phase of this work, an improvement to the surface inclination methods was developed. This used a novel method for including viscous effects by modifying the geometry to include the viscous/shock layer.
Neutral ion sources in precision manufacturing
NASA Technical Reports Server (NTRS)
Fawcett, Steven C.; Drueding, Thomas W.
1994-01-01
Ion figuring of optical components is a relatively new technology that can alleviate some of the problems associated with traditional contact polishing. Because the technique is non contacting, edge distortions and rib structure print through do not occur. This initial investigation was aimed at determining the effect of ion figuring on surface roughness of previously polished or ductile ground ceramic optical samples. This is the first step in research directed toward the combination of a pre-finishing process (ductile grinding or polishing) with ion figuring to produce finished ceramic mirrors. The second phase of the project is focusing on the development of mathematical algorithms that will deconvolve the ion beam profile from the surface figure errors so that these errors can be successfully removed from the optical components. In the initial phase of the project, multiple, chemical vapor deposited silicon carbide (CVD SiC) samples were polished or ductile ground to specular or near-specular roughness. These samples were then characterized to determine topographic surface information. The surface evaluation consisted of stylus profilometry, interferometry, and optical and scanning electron microscopy. The surfaces, were ion machined to depths from 0-5 microns. The finished surfaces were characterized to evaluate the effects of the ion machining process with respect to the previous processing methods and the pre-existing subsurface damage. The development of the control algorithms for figuring optical components has been completed. These algorithms have been validated with simulations and future experiments have been planned to verify the methods. This paper will present the results of the initial surface finish experiments and the control algorithms simulations.
DOT National Transportation Integrated Search
2011-08-01
This report documents the findings from the research that was carried out as part of Phase II of : TxDOT Project 0-5627. The research included measurements and analysis of mechanical and physical : properties of aggregates used in surface mixes in th...
PHASE I PILOT AIR CONVEYANCE SYSTEM DESIGN, CLEANING, AND CHARACTERIZATION
The report gives results of a project to develop and refine surface and airborne contamination
measurement techniques that can be used to evaluate air conveyance system (ACS) cleaning.
(NOTE: ACS cleaning is advertized to homeowners as a service having a number of benefits...
Northern California CO 2 Reduction Project
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hymes, Edward
2010-06-16
C6 Resources LLC, a wholly owned subsidiary of Shell Oil Company, worked with the US Department of Energy (DOE) under a Cooperative Agreement to develop the Northern California CO 2 Reduction Project. The objective of the Project is to demonstrate the viability of using Carbon Capture and Sequestration (CCS) to reduce existing greenhouse gas emissions from industrial sources on a large-scale. The Project will capture more than 700,000 metric tonnes of CO 2 per year, which is currently being vented to the atmosphere from the Shell Martinez Refinery in Contra Costa County. The CO 2 will be compressed and dehydratedmore » at the refinery and then transported via pipeline to a sequestration site in a rural area in neighboring Solano County. The CO 2 will be sequestered into a deep saline formation (more than two miles underground) and will be monitored to assure secure, long-term containment. The pipeline will be designed to carry as much as 1,400,000 metric tonnes of CO 2 per year, so additional capacity will be available to accommodate CO 2 captured from other industrial sources. The Project is expected to begin operation in 2015. The Project has two distinct phases. The overall objective of Phase 1 was to develop a fully definitive design basis for the Project. The Cooperative Agreement with the DOE provided cost sharing for Phase 1 and the opportunity to apply for additional DOE cost sharing for Phase 2, comprising the design, construction and operation of the Project. Phase 1 has been completed. DOE co-funding is provided by the American Recovery and Reinvestment Act (ARRA) of 2009. As prescribed by ARRA, the Project will stimulate the local economy by creating manufacturing, transportation, construction, operations, and management jobs while addressing the need to reduce greenhouse gas emissions at an accelerated pace. The Project, which will also assist in meeting the CO 2 reduction requirements set forth in California's Climate Change law, presents a major opportunity for both the environment as well as the region. C6 Resources is conducting the Project in collaboration with federally-funded research centers, such as Lawrence Berkeley National Lab and Lawrence Livermore National Lab. C6 Resources and Shell have identified CCS as one of the critical pathways toward a worldwide goal of providing cleaner energy. C6 Resources, in conjunction with the West Coast Regional Carbon Sequestration Partnership (WESTCARB), has conducted an extensive and ongoing public outreach and CCS education program for local, regional and state-wide stakeholders. As part of a long term relationship, C6 Resources will continue to engage directly with community leaders and residents to ensure public input and transparency. This topical report summarizes the technical work from Phase 1 of the Project in the following areas; Surface Facility Preliminary Engineering: summarizes the preliminary engineering work performed for CO 2 capture, CO 2 compression and dehydration at the refinery, and surface facilities at the sequestration site; Pipeline Preliminary Engineering: summarizes the pipeline routing study and preliminary engineering design; Geologic Sequestration: summarizes the work to characterize, model and evaluate the sequestration site; and Monitoring, Verification and Accounting (MVA): summarizes the MVA plan to assure long-term containment of the sequestered CO 2.« less
Broadband and chiral binary dielectric meta-holograms.
Khorasaninejad, Mohammadreza; Ambrosio, Antonio; Kanhaiya, Pritpal; Capasso, Federico
2016-05-01
Subwavelength structured surfaces, known as meta-surfaces, hold promise for future compact and optically thin devices with versatile functionalities. By revisiting the concept of detour phase, we demonstrate high-efficiency holograms with broadband and chiral imaging functionalities. In our devices, the apertures of binary holograms are replaced by subwavelength structured microgratings. We achieve broadband operation from the visible to the near infrared and efficiency as high as 75% in the 1.0 to 1.4 μm range by compensating for the inherent dispersion of the detour phase with that of the subwavelength structure. In addition, we demonstrate chiral holograms that project different images depending on the handedness of the reference beam by incorporating a geometric phase. Our devices' compactness, lightness, and ability to produce images even at large angles have significant potential for important emerging applications such as wearable optics.
Broadband and chiral binary dielectric meta-holograms
Khorasaninejad, Mohammadreza; Ambrosio, Antonio; Kanhaiya, Pritpal; Capasso, Federico
2016-01-01
Subwavelength structured surfaces, known as meta-surfaces, hold promise for future compact and optically thin devices with versatile functionalities. By revisiting the concept of detour phase, we demonstrate high-efficiency holograms with broadband and chiral imaging functionalities. In our devices, the apertures of binary holograms are replaced by subwavelength structured microgratings. We achieve broadband operation from the visible to the near infrared and efficiency as high as 75% in the 1.0 to 1.4 μm range by compensating for the inherent dispersion of the detour phase with that of the subwavelength structure. In addition, we demonstrate chiral holograms that project different images depending on the handedness of the reference beam by incorporating a geometric phase. Our devices’ compactness, lightness, and ability to produce images even at large angles have significant potential for important emerging applications such as wearable optics. PMID:27386518
Modeling for free surface flow with phase change and its application to fusion technology
NASA Astrophysics Data System (ADS)
Luo, Xiaoyong
The development of predictive capabilities for free surface flow with phase change is essential to evaluate liquid wall protection schemes for various fusion chambers. With inertial fusion energy (IFE) concepts such as HYLIFE-II, rapid condensation into cold liquid surfaces is required when using liquid curtains for protecting reactor walls from blasts and intense neutron radiation. With magnetic fusion energy (MFE) concepts, droplets are injected onto the free surface of the liquid to minimize evaporation by minimizing the surface temperature. This dissertation presents a numerical methodology for free surface flow with phase change to help resolve feasibility issues encountered in the aforementioned fusion engineering fields, especially spray droplet condensation efficiency in IFE and droplet heat transfer enhancement on free surface liquid divertors in MFE. The numerical methodology is being conducted within the framework of the incompressible flow with the phase change model. A new second-order projection method is presented in conjunction with Approximate-Factorization techniques (AF method) for incompressible Navier-Stokes equations. A sub-cell conception is introduced and the Ghost Fluid Method in extended in a modified mass transfer model to accurately calculate the mass transfer across the interface. The Crank-Nicholson method is used for the diffusion term to eliminate the numerical viscous stability restriction. The third-order ENO scheme is used for the convective term to guarantee the accuracy of the method. The level set method is used to capture accurately the free surface of the flow and the deformation of the droplets. This numerical investigation identifies the physics characterizing transient heat and mass transfer of the droplet and the free surface flow. The results show that the numerical methodology is quite successful in modeling the free surface with phase change even though some severe deformations such as breaking and merging occur. The versatility of the numerical methodology shows that the work can easily handle complex physical conditions that occur in the fusion science and engineering.
Altair Lunar Lander Development Status: Enabling Lunar Exploration
NASA Technical Reports Server (NTRS)
Laurini, Kathleen C.; Connolly, John F.
2009-01-01
As a critical part of the NASA Constellation Program lunar transportation architecture, the Altair lunar lander will return humans to the moon and enable a sustained program of lunar exploration. The Altair is to deliver up to four crew to the surface of the moon and return them to low lunar orbit at the completion of their mission. Altair will also be used to deliver large cargo elements to the lunar surface, enabling the buildup of an outpost. The Altair Project initialized its design using a "minimum functionality" approach that identified critical functionality required to meet a minimum set of Altair requirements. The Altair team then performed several analysis cycles using risk-informed design to selectively add back components and functionality to increase the vehicle's safety and reliability. The analysis cycle results were captured in a reference Altair design. This design was reviewed at the Constellation Lunar Capabilities Concept Review, a Mission Concept Review, where key driving requirements were confirmed and the Altair Project was given authorization to began Phase A project formulation. A key objective of Phase A is to revisit the Altair vehicle configuration, to better optimize it to complete its broad range of crew and cargo delivery missions. Industry was invited to partner with NASA early in the design to provide their insights regarding Altair configuration and key engineering challenges. NASA intends to continue to seek industry involvement in project formulation activities. This paper will update the international coimmunity on the status of the Altair Project as it addresses the challenges of project formulation, including optinuzing a vehicle configuration based on the work of the NASA Altair Project team, industry inputs and the plans going forward in designing the Altair lunar lander.
1985-06-28
1984 to April 1985 includedr installation of 27 raw mnitor wells and 11 amh l’,(1 zjit~s, collecticn cf seive~t, sarples ftw surfac , soil, shallowv...modifying a sampling and analytical program that addresses the requirements of the project. If project requirements necessitate different quality...reagent blank and at least five (5) different concentrations of thl analyte. A modification of the method of Hubaux and Vos will be used to deter
Critical Surface Cleaning and Verification Alternatives
NASA Technical Reports Server (NTRS)
Melton, Donald M.; McCool, A. (Technical Monitor)
2000-01-01
As a result of federal and state requirements, historical critical cleaning and verification solvents such as Freon 113, Freon TMC, and Trichloroethylene (TCE) are either highly regulated or no longer 0 C available. Interim replacements such as HCFC 225 have been qualified, however toxicity and future phase-out regulations necessitate long term solutions. The scope of this project was to qualify a safe and environmentally compliant LOX surface verification alternative to Freon 113, TCE and HCFC 225. The main effort was focused on initiating the evaluation and qualification of HCFC 225G as an alternate LOX verification solvent. The project was scoped in FY 99/00 to perform LOX compatibility, cleaning efficiency and qualification on flight hardware.
NASA Technical Reports Server (NTRS)
Vanalstine, James M.
1993-01-01
Project NAS8-36955 D.O. #100 initially involved the following tasks: (1) evaluation of various coatings' ability to control wall wetting and surface zeta potential expression; (2) testing various methods to mix and control the demixing of phase systems; and (3) videomicroscopic investigation of cell partition. Three complementary areas were identified for modification and extension of the original contract. They were: (1) identification of new supports for column cell partition; (2) electrokinetic detection of protein adsorption; and (3) emulsion studies related to bioseparations.
NASA Technical Reports Server (NTRS)
Sandy, Michael
2015-01-01
The Regolith Advanced Surface Systems Operations Robot (RASSOR) Phase 2 is an excavation robot for mining regolith on a planet like Mars. The robot is programmed using the Robotic Operating System (ROS) and it also uses a physical simulation program called Gazebo. This internship focused on various functions of the program in order to make it a more professional and efficient robot. During the internship another project called the Smart Autonomous Sand-Swimming Excavator was worked on. This is a robot that is designed to dig through sand and extract sample material. The intern worked on programming the Sand-Swimming robot, and designing the electrical system to power and control the robot.
NASA Technical Reports Server (NTRS)
Lee, Katharine
2004-01-01
The Surface Management System (SMS) is a decision support tool that will help controllers, traffic managers, and NAS users manage the movements of aircraft on the surface of busy airports, improving capacity, efficiency, and flexibility. The Advanced Air Transportation Technologies (AATT) Project at NASA is developing SMS in cooperation with the FAA's Free Flight Phase 2 (FFP2) pro5ram. SMS consists of three parts: a traffic management tool, a controller tool, and a National Airspace System (NAS) information tool.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Watson, D.; Leavitt, M.; Moss, D.
1997-03-01
Historical waste disposal activities within the Bear Creek Valley (BCV) Characterization Area (CA), at the U.S. Department of Energy (DOE) Oak Ridge Y-12 plant, have contaminated groundwater and surface water above human health risk levels and impacted the ecology of Bear Creek. Contaminates include nitrate, radioisotopes, metals, volatile organic chemicals (VOCS), and common ions. This paper provides a status report on a technology demonstration project that is investigating the feasibility of using passive in situ treatment systems to remove these contaminants. Although this technology may be applicable to many locations at the Oak Ridge Y-12 Plant, the project focuses onmore » collecting the information needed to take CERCLA removal actions in 1998 at the S-3 Disposal Ponds site. Phase 1 has been completed and included site characterization, laboratory screening of treatment media (sorbents; and iron), and limited field testing of biological treatment systems. Batch tests using different Y-12 Plant waters were conducted to evaluate the removal efficiencies of most of the media. Phase 1 results suggest that the most promising treatment media are Dowex 21 k resin, peat moss, zero-valent iron, and iron oxides. Phase 2 will include in-field column testing of these media to assess loading rates, and concerns with clogging, by-products, and long-term treatment efficiency and media stability. Continued testing of wetlands and algal mats (MATs) will be conducted to determine if they can be used for in-stream polishing of surface water. Hydraulic testing of a shallow trench and horizontal well will also be completed during Phase 2. 4 refs., 3 tabs.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
The Liquid Phase Methanol (LPMEOH{trademark}) Demonstration Project at Kingsport, Tennessee, is a $213.7 million cooperative agreement between the US Department of Energy (DOE) and Air Products Liquid Phase Conversion Company, L.P. (the Partnership). The LPMEOH{trademark} Process Demonstration Unit is being built at a site located at the Eastman Chemical Company (Eastman) complex in Kingsport. The project involves the construction of an 80,000 gallons per day (260 tons per day (TPD)) methanol unit utilizing coal-derived synthesis gas from Eastman`s integrated coal gasification facility. The new equipment consists of synthesis gas feed preparation and compression facilities, the liquid phase reactor and auxiliaries,more » product distillation facilities, and utilities. This liquid phase process suspends fine catalyst particles in an inert liquid, forming a slurry. The slurry dissipates the heat of the chemical reaction away from the catalyst surface, protecting the catalyst and allowing the methanol synthesis reaction to proceed at higher rates. At the Eastman complex, the technology is being integrated with existing coal-gasifiers.« less
NASA Astrophysics Data System (ADS)
Zhang, Chengzhu; Xie, Shaocheng; Klein, Stephen A.; Ma, Hsi-yen; Tang, Shuaiqi; Van Weverberg, Kwinten; Morcrette, Cyril J.; Petch, Jon
2018-03-01
All the weather and climate models participating in the Clouds Above the United States and Errors at the Surface project show a summertime surface air temperature (T2 m) warm bias in the region of the central United States. To understand the warm bias in long-term climate simulations, we assess the Atmospheric Model Intercomparison Project simulations from the Coupled Model Intercomparison Project Phase 5, with long-term observations mainly from the Atmospheric Radiation Measurement program Southern Great Plains site. Quantities related to the surface energy and water budget, and large-scale circulation are analyzed to identify possible factors and plausible links involved in the warm bias. The systematic warm season bias is characterized by an overestimation of T2 m and underestimation of surface humidity, precipitation, and precipitable water. Accompanying the warm bias is an overestimation of absorbed solar radiation at the surface, which is due to a combination of insufficient cloud reflection and clear-sky shortwave absorption by water vapor and an underestimation in surface albedo. The bias in cloud is shown to contribute most to the radiation bias. The surface layer soil moisture impacts T2 m through its control on evaporative fraction. The error in evaporative fraction is another important contributor to T2 m. Similar sources of error are found in hindcast from other Clouds Above the United States and Errors at the Surface studies. In Atmospheric Model Intercomparison Project simulations, biases in meridional wind velocity associated with the low-level jet and the 500 hPa vertical velocity may also relate to T2 m bias through their control on the surface energy and water budget.
Development of an Advanced Computational Model for OMCVD of Indium Nitride
NASA Technical Reports Server (NTRS)
Cardelino, Carlos A.; Moore, Craig E.; Cardelino, Beatriz H.; Zhou, Ning; Lowry, Sam; Krishnan, Anantha; Frazier, Donald O.; Bachmann, Klaus J.
1999-01-01
An advanced computational model is being developed to predict the formation of indium nitride (InN) film from the reaction of trimethylindium (In(CH3)3) with ammonia (NH3). The components are introduced into the reactor in the gas phase within a background of molecular nitrogen (N2). Organometallic chemical vapor deposition occurs on a heated sapphire surface. The model simulates heat and mass transport with gas and surface chemistry under steady state and pulsed conditions. The development and validation of an accurate model for the interactions between the diffusion of gas phase species and surface kinetics is essential to enable the regulation of the process in order to produce a low defect material. The validation of the model will be performed in concert with a NASA-North Carolina State University project.
NASA Astrophysics Data System (ADS)
Halios, Christos H.; Barlow, Janet F.
2018-03-01
The study of the boundary layer can be most difficult when it is in transition and forced by a complex surface, such as an urban area. Here, a novel combination of ground-based remote sensing and in situ instrumentation in central London, UK, is deployed, aiming to capture the full evolution of the urban boundary layer (UBL) from night-time until the fully-developed convective phase. In contrast with the night-time stable boundary layer observed over rural areas, the night-time UBL is weakly convective. Therefore, a new approach for the detection of the morning-transition and rapid-growth phases is introduced, based on the sharp, quasi-linear increase of the mixing height. The urban morning-transition phase varied in duration between 0.5 and 4 h and the growth rate of the mixing layer during the rapid-growth phase had a strong positive relationship with the convective velocity scale, and a weaker, negative relationship with wind speed. Wind shear was found to be higher during the night-time and morning-transition phases than the rapid-growth phase and the shear production of turbulent kinetic energy near the mixing-layer top was around six times larger than surface shear production in summer, and around 1.5 times larger in winter. In summer under low winds, low-level jets dominated the UBL, and shear production was greater than buoyant production during the night-time and the morning-transition phase near the mixing-layer top. Within the rapid-growth phase, buoyant production dominated at the surface, but shear production dominated in the upper half of the UBL. These results imply that regional flows such as low-level jets play an important role alongside surface forcing in determining UBL structure and growth.
Early 20th-century Arctic warming intensified by Pacific and Atlantic multidecadal variability
Tokinaga, Hiroki; Xie, Shang-Ping; Mukougawa, Hitoshi
2017-01-01
With amplified warming and record sea ice loss, the Arctic is the canary of global warming. The historical Arctic warming is poorly understood, limiting our confidence in model projections. Specifically, Arctic surface air temperature increased rapidly over the early 20th century, at rates comparable to those of recent decades despite much weaker greenhouse gas forcing. Here, we show that the concurrent phase shift of Pacific and Atlantic interdecadal variability modes is the major driver for the rapid early 20th-century Arctic warming. Atmospheric model simulations successfully reproduce the early Arctic warming when the interdecadal variability of sea surface temperature (SST) is properly prescribed. The early 20th-century Arctic warming is associated with positive SST anomalies over the tropical and North Atlantic and a Pacific SST pattern reminiscent of the positive phase of the Pacific decadal oscillation. Atmospheric circulation changes are important for the early 20th-century Arctic warming. The equatorial Pacific warming deepens the Aleutian low, advecting warm air into the North American Arctic. The extratropical North Atlantic and North Pacific SST warming strengthens surface westerly winds over northern Eurasia, intensifying the warming there. Coupled ocean–atmosphere simulations support the constructive intensification of Arctic warming by a concurrent, negative-to-positive phase shift of the Pacific and Atlantic interdecadal modes. Our results aid attributing the historical Arctic warming and thereby constrain the amplified warming projected for this important region. PMID:28559341
Higher-dimensional phase imaging
NASA Astrophysics Data System (ADS)
Huntley, Jonathan M.
2010-04-01
Traditional full-field interferometric techniques (speckle, moiré, holography etc) provide 2-D phase images, which encode the surface deformation state of the object under test. Over the past 15 years, the use of additional spatial or temporal dimensions has been investigated by a number of research groups. Early examples include the measurement of 3-D surface profiles by temporally-varying projected fringe patterns, and dynamic speckle interferometry. More recently (the past 5 years) a family of related techniques (Wavelength Scanning Interferometry, Phase Contrast Spectral Optical Coherence Tomography (OCT), and Tilt Scanning Interferometry) has emerged that provides the volume deformation state of the object. The techniques can be thought of as a marriage between the phase sensing capabilities of Phase Shifting Interferometry and the depth-sensing capabilities of OCT. Finally, in the past 12 months a technique called Hyperspectral Interferometry has been proposed in which absolute optical path distributions are obtained in a single shot through the spectral decomposition of a white light interferogram, and for which the additional dimension therefore corresponds to the illumination wavenumber. An overview of these developments, and the related issue of robust phase unwrapping of noisy 3-D wrapped phase volumes, is presented in this paper.
NASA Astrophysics Data System (ADS)
Barrett, B.; Davies, A. R.; Steppe, C. N.; Hackbarth, C.
2017-12-01
In the first part of this study, time-lagged composites of upper-ocean currents from February to May of 1993-2016 were binned by active phase of the leading atmospheric mode of intraseasonal variability, the Madden-Julian Oscillation (MJO). Seven days after the convectively active phase of the MJO enters the tropical Indian Ocean, anomalously strong south-southeastward upper-ocean currents are observed along the majority of U.S. west coast. Seven days after the convectively active phase enters the tropical western Pacific Ocean, upper-ocean current anomalies reverse along the U.S. west coast, with weaker southward flow. A physical pathway to the ocean was found for both of these: (a) tropical MJO convection modulates upper-tropospheric heights and circulation over the Pacific Ocean; (b) those anomalous atmospheric heights adjust the strength and position of the Aleutian Low and Hawaiian High; (c) surface winds change in response to the adjusted atmospheric pressure patterns; and (d) those surface winds project onto upper-ocean currents. In the second part of this study, we investigated if the MJO modulated intraseasonal variability of surface wind forcing and upper-ocean currents projected onto phytoplankton abundance along the U.S. west coast. Following a similar methodology, time-lagged, level 3 chlorophyll-a satellite products (a proxy for photosynthetic primary production) were binned by active MJO phase and analyzed for statistical significance using the Student's t test. Results suggest that intraseasonal variability of biological production along the U.S. west coast may be linked to the MJO, particularly since the time scale of the life cycle of phytoplankton is similar to the time scale of the MJO.
NASA Astrophysics Data System (ADS)
Meitav, Omri; Shaul, Oren; Abookasis, David
2018-03-01
A practical algorithm for estimating the wavelength-dependent refractive index (RI) of a turbid sample in the spatial frequency domain with the aid of Kramers-Kronig (KK) relations is presented. In it, phase-shifted sinusoidal patterns (structured illumination) are serially projected at a high spatial frequency onto the sample surface (mouse scalp) at different near-infrared wavelengths while a camera mounted normally to the sample surface captures the reflected diffuse light. In the offline analysis pipeline, recorded images at each wavelength are converted to spatial absorption maps by logarithmic function, and once the absorption coefficient information is obtained, the imaginary part (k) of the complex RI (CRI), based on Maxell's equations, can be calculated. Using the data represented by k, the real part of the CRI (n) is then resolved by KK analysis. The wavelength dependence of n ( λ ) is then fitted separately using four standard dispersion models: Cornu, Cauchy, Conrady, and Sellmeier. In addition, three-dimensional surface-profile distribution of n is provided based on phase profilometry principles and a phase-unwrapping-based phase-derivative-variance algorithm. Experimental results demonstrate the capability of the proposed idea for sample's determination of a biological sample's RI value.
NASA Technical Reports Server (NTRS)
Gern, Frank; Vicroy, Dan D.; Mulani, Sameer B.; Chhabra, Rupanshi; Kapania, Rakesh K.; Schetz, Joseph A.; Brown, Derrell; Princen, Norman H.
2014-01-01
Traditional methods of control allocation optimization have shown difficulties in exploiting the full potential of controlling large arrays of control devices on innovative air vehicles. Artificial neutral networks are inspired by biological nervous systems and neurocomputing has successfully been applied to a variety of complex optimization problems. This project investigates the potential of applying neurocomputing to the control allocation optimization problem of Hybrid Wing Body (HWB) aircraft concepts to minimize control power, hinge moments, and actuator forces, while keeping system weights within acceptable limits. The main objective of this project is to develop a proof-of-concept process suitable to demonstrate the potential of using neurocomputing for optimizing actuation power for aircraft featuring multiple independently actuated control surfaces. A Nastran aeroservoelastic finite element model is used to generate a learning database of hinge moment and actuation power characteristics for an array of flight conditions and control surface deflections. An artificial neural network incorporating a genetic algorithm then uses this training data to perform control allocation optimization for the investigated aircraft configuration. The phase I project showed that optimization results for the sum of required hinge moments are improved by more than 12% over the best Nastran solution by using the neural network optimization process.
Rapid matching of stereo vision based on fringe projection profilometry
NASA Astrophysics Data System (ADS)
Zhang, Ruihua; Xiao, Yi; Cao, Jian; Guo, Hongwei
2016-09-01
As the most important core part of stereo vision, there are still many problems to solve in stereo matching technology. For smooth surfaces on which feature points are not easy to extract, this paper adds a projector into stereo vision measurement system based on fringe projection techniques, according to the corresponding point phases which extracted from the left and right camera images are the same, to realize rapid matching of stereo vision. And the mathematical model of measurement system is established and the three-dimensional (3D) surface of the measured object is reconstructed. This measurement method can not only broaden application fields of optical 3D measurement technology, and enrich knowledge achievements in the field of optical 3D measurement, but also provide potential possibility for the commercialized measurement system in practical projects, which has very important scientific research significance and economic value.
Altair Lunar Lander Development Status: Enabling Human Lunar Exploration
NASA Technical Reports Server (NTRS)
Laurini, Kathleen C.; Connolly, John F.
2009-01-01
As a critical part of the NASA Constellation Program lunar transportation architecture, the Altair lunar lander will return humans to the moon and enable a sustained program of lunar exploration. The Altair is to deliver up to four crew to the surface of the moon and return them to low lunar orbit at the completion of their mission. Altair will also be used to deliver large cargo elements to the lunar surface, enabling the buildup of an outpost. The Altair Project initialized its design using a minimum functionality approach that identified critical functionality required to meet a minimum set of Altair requirements. The Altair team then performed several analysis cycles using risk-informed design to selectively add back components and functionality to increase the vehicles safety and reliability. The analysis cycle results were captured in a reference Altair design. This design was reviewed at the Constellation Lunar Capabilities Concept Review, a Mission Concept Review, where key driving requirements were confirmed and the Altair Project was given authorization to begin Phase A project formulation. A key objective of Phase A is to revisit the Altair vehicle configuration, to better optimize it to complete its broad range of crew and cargo delivery missions. Industry was invited to partner with NASA early in the design to provide their insights regarding Altair configuration and key engineering challenges. A blended NASA-industry team will continue to refine the lander configuration and mature the vehicle design over the next few years. This paper will update the international community on the status of the Altair Project as it addresses the challenges of project formulation, including optimizing a vehicle configuration based on the work of the NASA Altair Project team, industry inputs and the plans going forward in designing the Altair lunar lander.
NASA Astrophysics Data System (ADS)
Parhi, P.; Giannini, A.; Lall, U.; Gentine, P.
2016-12-01
Assessing and managing risks posed by climate variability and change is challenging in the tropics, from both a socio-economic and a scientific perspective. Most of the vulnerable countries with a limited climate adaptation capability are in the tropics. However, climate projections, particularly of extreme precipitation, are highly uncertain there. The CMIP5 (Coupled Model Inter- comparison Project - Phase 5) inter-model range of extreme precipitation sensitivity to the global temperature under climate change is much larger in the tropics as compared to the extra-tropics. It ranges from nearly 0% to greater than 30% across models (O'Gorman 2012). The uncertainty is also large in historical gauge or satellite based observational records. These large uncertainties in the sensitivity of tropical precipitation extremes highlight the need to better understand how tropical precipitation extremes respond to warming. We hypothesize that one of the factors explaining the large uncertainty is due to differing sensitivities during different phases of warming. We consider the `growth' and `mature' phases of warming under climate variability case- typically associated with an El Niño event. In the remote tropics (away from tropical Pacific Ocean), the response of the precipitation extremes during the two phases can be through different pathways: i) a direct and fast changing radiative forcing in an atmospheric column, acting top-down due to the tropospheric warming, and/or ii) an indirect effect via changes in surface temperatures, acting bottom-up through surface water and energy fluxes. We also speculate that the insights gained here might be useful in interpreting the large sensitivity under climate change scenarios, since the physical mechanisms during the two warming phases under climate variability case, have some correspondence with an increasing and stabilized green house gas emission scenarios.
Automatic generation of endocardial surface meshes with 1-to-1 correspondence from cine-MR images
NASA Astrophysics Data System (ADS)
Su, Yi; Teo, S.-K.; Lim, C. W.; Zhong, L.; Tan, R. S.
2015-03-01
In this work, we develop an automatic method to generate a set of 4D 1-to-1 corresponding surface meshes of the left ventricle (LV) endocardial surface which are motion registered over the whole cardiac cycle. These 4D meshes have 1- to-1 point correspondence over the entire set, and is suitable for advanced computational processing, such as shape analysis, motion analysis and finite element modelling. The inputs to the method are the set of 3D LV endocardial surface meshes of the different frames/phases of the cardiac cycle. Each of these meshes is reconstructed independently from border-delineated MR images and they have no correspondence in terms of number of vertices/points and mesh connectivity. To generate point correspondence, the first frame of the LV mesh model is used as a template to be matched to the shape of the meshes in the subsequent phases. There are two stages in the mesh correspondence process: (1) a coarse matching phase, and (2) a fine matching phase. In the coarse matching phase, an initial rough matching between the template and the target is achieved using a radial basis function (RBF) morphing process. The feature points on the template and target meshes are automatically identified using a 16-segment nomenclature of the LV. In the fine matching phase, a progressive mesh projection process is used to conform the rough estimate to fit the exact shape of the target. In addition, an optimization-based smoothing process is used to achieve superior mesh quality and continuous point motion.
Investigation of advanced phase-shifting projected fringe profilometry techniques
NASA Astrophysics Data System (ADS)
Liu, Hongyu
1999-11-01
The phase-shifting projected fringe profilometry (PSPFP) technique is a powerful tool in the profile measurements of rough engineering surfaces. Compared with other competing techniques, this technique is notable for its full-field measurement capacity, system simplicity, high measurement speed, and low environmental vulnerability. The main purpose of this dissertation is to tackle three important problems, which severely limit the capability and the accuracy of the PSPFP technique, with some new approaches. Chapter 1 provides some background information of the PSPFP technique including the measurement principles, basic features, and related techniques is briefly introduced. The objectives and organization of the thesis are also outlined. Chapter 2 gives a theoretical treatment to the absolute PSPFP measurement. The mathematical formulations and basic requirements of the absolute PSPFP measurement and its supporting techniques are discussed in detail. Chapter 3 introduces the experimental verification of the proposed absolute PSPFP technique. Some design details of a prototype system are discussed as supplements to the previous theoretical analysis. Various fundamental experiments performed for concept verification and accuracy evaluation are introduced together with some brief comments. Chapter 4 presents the theoretical study of speckle- induced phase measurement errors. In this analysis, the expression for speckle-induced phase errors is first derived based on the multiplicative noise model of image- plane speckles. The statistics and the system dependence of speckle-induced phase errors are then thoroughly studied through numerical simulations and analytical derivations. Based on the analysis, some suggestions on the system design are given to improve measurement accuracy. Chapter 5 discusses a new technique combating surface reflectivity variations. The formula used for error compensation is first derived based on a simplified model of the detection process. The techniques coping with two major effects of surface reflectivity variations are then introduced. Some fundamental problems in the proposed technique are studied through simulations. Chapter 6 briefly summarizes the major contributions of the current work and provides some suggestions for the future research.
Topological Weyl superconductor to diffusive thermal Hall metal crossover in the B phase of UPt3
NASA Astrophysics Data System (ADS)
Goswami, Pallab; Nevidomskyy, Andriy H.
2015-12-01
The recent phase-sensitive measurements in the superconducting B phase of UPt3 provide strong evidence for the triplet, chiral kz(kx±i ky) 2 pairing symmetries, which endow the Cooper pairs with orbital angular momentum projections Lz=±2 along the c axis. In the absence of disorder such pairing can support both line and point nodes, and both types of nodal quasiparticles exhibit nontrivial topology in the momentum space. The point nodes, located at the intersections of the closed Fermi surfaces with the c axis, act as the double monopoles and the antimonopoles of the Berry curvature, and generalize the notion of Weyl quasiparticles. Consequently, the B phase should support an anomalous thermal Hall effect, the polar Kerr effect, in addition to the protected Fermi arcs on the (1 ,0 ,0 ) and the (0 ,1 ,0 ) surfaces. The line node at the Fermi surface equator acts as a vortex loop in the momentum space and gives rise to the zero-energy, dispersionless Andreev bound states on the (0 ,0 ,1 ) surface. At the transition from the B phase to the A phase, the time-reversal symmetry is restored, and only the line node survives inside the A phase. As both line and double-Weyl point nodes possess linearly vanishing density of states, we show that weak disorder acts as a marginally relevant perturbation. Consequently, an infinitesimal amount of disorder destroys the ballistic quasiparticle pole, while giving rise to a diffusive phase with a finite density of states at the zero energy. The resulting diffusive phase exhibits T -linear specific heat, and an anomalous thermal Hall effect. We predict that the low-temperature thermodynamic and transport properties display a crossover between a ballistic thermal Hall semimetal and a diffusive thermal Hall metal. By contrast, the diffusive phase obtained from a time-reversal-invariant pairing exhibits only the T -linear specific heat without any anomalous thermal Hall effect.
NASA Technical Reports Server (NTRS)
Saunders, R. S.; Spear, A. J.; Allin, P. C.; Austin, R. S.; Berman, A. L.; Chandlee, R. C.; Clark, J.; Decharon, A. V.; De Jong, E. M.; Griffith, D. G.
1992-01-01
Magellan started mapping the planet Venus on September 15, 1990, and after one cycle (one Venus day or 243 earth days) had mapped 84 percent of the planet's surface. This returned an image data volume greater than all past planetary missions combined. Spacecraft problems were experienced in flight. Changes in operational procedures and reprogramming of onboard computers minimized the amount of mapping data lost. Magellan data processing is the largest planetary image-processing challenge to date. Compilation of global maps of tectonic and volcanic features, as well as impact craters and related phenomena and surface processes related to wind, weathering, and mass wasting, has begun. The Magellan project is now in an extended mission phase, with plans for additional cycles out to 1995. The Magellan project will fill in mapping gaps, obtain a global gravity data set between mid-September 1992 and May 1993, acquire images at different view angles, and look for changes on the surface from one cycle to another caused by surface activity such as volcanism, faulting, or wind activity.
Surface electrical properties experiment study phase, volume 3
NASA Technical Reports Server (NTRS)
1973-01-01
The reliability and quality assurance system and procedures used in developing test equipment for the Lunar Experiment projects are described. The subjects discussed include the following: (1) documentation control, (2) design review, (3) parts and materials selection, (4) material procurement, (5) inspection procedures, (6) qualification and special testing, and failure modes and effects analysis.
NASA Astrophysics Data System (ADS)
Wengel, C.; Latif, M.; Park, W.; Harlaß, J.; Bayr, T.
2018-02-01
The El Niño/Southern Oscillation (ENSO) is characterized by a seasonal phase locking, with strongest eastern and central equatorial Pacific sea surface temperature (SST) anomalies during boreal winter and weakest SST anomalies during boreal spring. In this study, key feedbacks controlling seasonal ENSO phase locking in the Kiel Climate Model (KCM) are identified by employing Bjerknes index stability analysis. A large ensemble of simulations with the KCM is analyzed, where the individual runs differ in either the number of vertical atmospheric levels or coefficients used in selected atmospheric parameterizations. All integrations use the identical ocean model. The ensemble-mean features realistic seasonal ENSO phase locking. ENSO phase locking is very sensitive to changes in the mean-state realized by the modifications described above. An excessive equatorial cold tongue leads to weak phase locking by reducing the Ekman feedback and thermocline feedback in late boreal fall and early boreal winter. Seasonal ENSO phase locking also is sensitive to the shortwave feedback as part of the thermal damping in early boreal spring, which strongly depends on eastern and central equatorial Pacific SST. The results obtained from the KCM are consistent with those from models participating in the Coupled Model Intercomparison Project phase 5 (CMIP5).
Nonlinear climate sensitivity and its implications for future greenhouse warming.
Friedrich, Tobias; Timmermann, Axel; Tigchelaar, Michelle; Elison Timm, Oliver; Ganopolski, Andrey
2016-11-01
Global mean surface temperatures are rising in response to anthropogenic greenhouse gas emissions. The magnitude of this warming at equilibrium for a given radiative forcing-referred to as specific equilibrium climate sensitivity ( S )-is still subject to uncertainties. We estimate global mean temperature variations and S using a 784,000-year-long field reconstruction of sea surface temperatures and a transient paleoclimate model simulation. Our results reveal that S is strongly dependent on the climate background state, with significantly larger values attained during warm phases. Using the Representative Concentration Pathway 8.5 for future greenhouse radiative forcing, we find that the range of paleo-based estimates of Earth's future warming by 2100 CE overlaps with the upper range of climate simulations conducted as part of the Coupled Model Intercomparison Project Phase 5 (CMIP5). Furthermore, we find that within the 21st century, global mean temperatures will very likely exceed maximum levels reconstructed for the last 784,000 years. On the basis of temperature data from eight glacial cycles, our results provide an independent validation of the magnitude of current CMIP5 warming projections.
Nonlinear climate sensitivity and its implications for future greenhouse warming
Friedrich, Tobias; Timmermann, Axel; Tigchelaar, Michelle; Elison Timm, Oliver; Ganopolski, Andrey
2016-01-01
Global mean surface temperatures are rising in response to anthropogenic greenhouse gas emissions. The magnitude of this warming at equilibrium for a given radiative forcing—referred to as specific equilibrium climate sensitivity (S)—is still subject to uncertainties. We estimate global mean temperature variations and S using a 784,000-year-long field reconstruction of sea surface temperatures and a transient paleoclimate model simulation. Our results reveal that S is strongly dependent on the climate background state, with significantly larger values attained during warm phases. Using the Representative Concentration Pathway 8.5 for future greenhouse radiative forcing, we find that the range of paleo-based estimates of Earth’s future warming by 2100 CE overlaps with the upper range of climate simulations conducted as part of the Coupled Model Intercomparison Project Phase 5 (CMIP5). Furthermore, we find that within the 21st century, global mean temperatures will very likely exceed maximum levels reconstructed for the last 784,000 years. On the basis of temperature data from eight glacial cycles, our results provide an independent validation of the magnitude of current CMIP5 warming projections. PMID:28861462
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shen, Weidian
This project, “Building Surface Science Capacity to Serve the Automobile Industry in Southeastern Michigan” was carried out in two phases: (1) the 2009 – 2012 renovation of space in the new EMU Science Complex, which included the Surface Science Laboratory (SSL), a very vigorous research lab at EMU that carries on a variety of research projects to serve the auto and other industries in Michigan; and (2) the 2013 purchase of several pieces of equipment to further enhance the research capability of the SSL. The funding granted by the DoE was proposed to “renovate the space in the Science Complexmore » to include SSL and purchase equipment for tribological and electrochemical impedance measurements in the lab, thus SSL will serve the auto and other industries in Michigan better.” We believe we have fully accomplished the mission.« less
NASA Technical Reports Server (NTRS)
Bose, Deepak
2012-01-01
The design of entry vehicles requires predictions of aerothermal environment during the hypersonic phase of their flight trajectories. These predictions are made using computational fluid dynamics (CFD) codes that often rely on physics and chemistry models of nonequilibrium processes. The primary processes of interest are gas phase chemistry, internal energy relaxation, electronic excitation, nonequilibrium emission and absorption of radiation, and gas-surface interaction leading to surface recession and catalytic recombination. NASAs Hypersonics Project is advancing the state-of-the-art in modeling of nonequilibrium phenomena by making detailed spectroscopic measurements in shock tube and arcjets, using ab-initio quantum mechanical techniques develop fundamental chemistry and spectroscopic databases, making fundamental measurements of finite-rate gas surface interactions, implementing of detailed mechanisms in the state-of-the-art CFD codes, The development of new models is based on validation with relevant experiments. We will present the latest developments and a roadmap for the technical areas mentioned above
Ferritin nanocontainers that self-direct in synthetic polymer systems
NASA Astrophysics Data System (ADS)
Sengonul, Merih C.
Currently, there are many approaches to introduce functionality into synthetic polymers. Among these, for example, are copolymerization, grafting, and blending methods. However, modifications made by such methods also change the thermodynamics and rheological properties of the polymer system of interest, and each new modification often requires a costly reoptimization of polymer processing. Such a reoptimalization would not be necessary if new functionality could be introduced via a container whose external surface is chemically and physically tuned to interact with the parent polymer. The contents of the container could then be changed without changing other important properties of the parent polymer. In this context this thesis project explores an innovative nanocontainer platform which can be introduced into phase-separating homopolymer blends. Ferritin is a naturally existing nanocontainer that can be used synthetically to package and selectively transport functional moieties to a particular phase that is either in the bulk or on the surface of a homopolymer blend system. The principal focus of this work centers on modifying the surface of wild ferritin to: (1) render modified ferritin soluble in a non-aqueous solvent; and (2) impart it with self-directing properties when exposed to a homopolymer blend surface or incorporated into the bulk of a homopolymer blend. Wild ferritin is water soluble, and this research project successfully modified wild ferritin by grafting either amine-functional poly(ethylene glycol) (PEG) or short-chain alkanes to carbodiimide activated carboxylate groups on ferritin's surface. Such modified ferritin is soluble in dichloromethane (DCM). Modification was confirmed by ion-exchange chromatography, zeta-potential measurements, and electrospray mass spectroscopy. FT-IR was used to quantify the extent of PEGylation of the reaction products through area ratios of the -C-O-C asymmetric stretching vibration of the grafted PEG chains to the carbonyl stretching vibration (amide I band) of the protein. The dimensionless grafting density after PEGylation was found to be 0.13 with 120 average grafted PEG chains per ferritin nanocontainer. Modified ferritin was used for bulk modification of a phase-separated polymer blend of poly(desaminotyrosyl tyrosine dodecyl ester carbonate) [PDTD] and PEG. TEM micrographs showed remarkable selectivity of PEGylated ferritin to PEG domains, while alkylated ferritin self-directs to the PDTD matrix. We explain this strong selectivity by the favourable interaction energies between the grafted and free matrix chains. In addition, both modified and wild ferritin were used for surface modification of the phase-separated homopolymer blend of PDTD and poly(ε-caprolactone) (PCL). At physiological pH wild ferritin selectively adsorbed onto the PDTD phase, while alkylated ferritin showed a striking selectivity to PCL phase. We attribute this behavior to the increase in protein's pI point above physiological pH after modification, which changes the electrostatic interactions between the ferritin and the polymer surface. Collectively, these results demonstrate the versatile use of ferritin as a model nanocontainer for the selective modification of surface and bulk properties of polymers.
Radarsat Antarctic Mapping Project: Antarctic Imaging Campaign 2
NASA Technical Reports Server (NTRS)
2001-01-01
The Radarsat Antarctic Mapping Project is a collaboration between NASA and the Canadian Space Agency to map Antarctica using synthetic aperture radar (SAR). The first Antarctic Mapping Mission (AMM-1) was successfully completed in October 1997. Data from the acquisition phase of the 1997 campaign have been used to achieve the primary goal of producing the first, high-resolution SAR image map of Antarctica. The limited amount of data suitable for interferometric analysis have also been used to produce remarkably detailed maps of surface velocity for a few selected regions. Most importantly, the results from AMM-1 are now available to the general science community in the form of various resolution, radiometrically calibrated and geometrically accurate image mosaics. The second Antarctic imaging campaign occurred during the fall of 2000. Modified from AMM-1, the satellite remained in north looking mode during AMM-2 restricting coverage to regions north of about -80 degrees latitude. But AMM-2 utilized for the first time RADARSAT-1 fine beams providing an unprecedented opportunity to image many of Antarctica's fast glaciers whose extent was revealed through AMM-1 data. AMM-2 also captured extensive data suitable for interferometric analysis of the surface velocity field. This report summarizes the science goals, mission objectives, and project status through the acquisition phase and the start of the processing phase. The reports describes the efforts of team members including Alaska SAR Facility, Jet Propulsion Laboratory, Vexcel Corporation, Goddard Space Flight Center, Wallops Flight Facility, Ohio State University, Environmental Research Institute of Michigan, White Sands Facility, Canadian Space Agency Mission Planning and Operations Groups, and the Antarctic Mapping Planning Group.
Flight Test of the F/A-18 Active Aeroelastic Wing Airplane
NASA Technical Reports Server (NTRS)
Clarke, Robert; Allen, Michael J.; Dibley, Ryan P.; Gera, Joseph; Hodgkinson, John
2005-01-01
Successful flight-testing of the Active Aeroelastic Wing airplane was completed in March 2005. This program, which started in 1996, was a joint activity sponsored by NASA, Air Force Research Laboratory, and industry contractors. The test program contained two flight test phases conducted in early 2003 and early 2005. During the first phase of flight test, aerodynamic models and load models of the wing control surfaces and wing structure were developed. Design teams built new research control laws for the Active Aeroelastic Wing airplane using these flight-validated models; and throughout the final phase of flight test, these new control laws were demonstrated. The control laws were designed to optimize strategies for moving the wing control surfaces to maximize roll rates in the transonic and supersonic flight regimes. Control surface hinge moments and wing loads were constrained to remain within hydraulic and load limits. This paper describes briefly the flight control system architecture as well as the design approach used by Active Aeroelastic Wing project engineers to develop flight control system gains. Additionally, this paper presents flight test techniques and comparison between flight test results and predictions.
FutureGen 2.0 Pipeline and Regional Carbon Capture Storage Project - Final Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Burger, Chris; Wortman, David; Brown, Chris
The U.S. Department of Energy’s (DOE) FutureGen 2.0 Program involves two projects: (1) the Oxy-Combustion Power Plant Project and (2) the CO2 Pipeline and Storage Project. This Final Technical Report is focused on the CO2 Pipeline and Storage Project. The FutureGen 2.0 CO2 Pipeline and Storage Project evolved from an initial siting and project definition effort in Phase I, into the Phase II activity consisting permitting, design development, the acquisition of land rights, facility design, and licensing and regulatory approvals. Phase II also progressed into construction packaging, construction procurement, and targeted early preparatory activities in the field. The CO2 Pipelinemore » and Storage Project accomplishments were significant, and in some cases unprecedented. The engineering, permitting, legal, stakeholder, and commercial learnings substantially advance the nation’s understanding of commercial-scale CO2 storage in deep saline aquifers. Voluminous and significant information was obtained from the drilling and the testing program of the subsurface, and sophisticated modeling was performed that held up to a wide range of scrutiny. All designs progressed to the point of securing construction contracts or comfort letters attesting to successful negotiation of all contract terms and willing execution at the appropriate time all major project elements – pipeline, surface facilities, and subsurface – as well as operations. While the physical installation of the planned facilities did not proceed in part due to insufficient time to complete the project prior to the expiration of federal funding, the project met significant objectives prior to DOE’s closeout decision. Had additional time been available, there were no known, insurmountable obstacles that would have precluded successful construction and operation of the project. Due to the suspension of the project, site restoration activities were developed and the work was accomplished. The site restoration efforts are also documented in this report. All permit applications had been submitted to all agencies for those permits or approvals required prior to the start of project construction. Most of the requisite permits were received during Phase II. This report includes information on each permitting effort. Successes and lessons learned are included in this report that will add value to the next generation of carbon storage efforts.« less
NASA Astrophysics Data System (ADS)
Feng, Shijie; Zhang, Yuzhen; Chen, Qian; Zuo, Chao; Li, Rubin; Shen, Guochen
2014-08-01
This paper presents a general solution for realizing high dynamic range three-dimensional (3-D) shape measurement based on fringe projection. Three concrete techniques are involved in the solution for measuring object with large range of reflectivity (LRR) or one with shiny specular surface. For the first technique, the measured surface reflectivities are sub-divided into several groups based on its histogram distribution, then the optimal exposure time for each group can be predicted adaptively so that the bright as well as dark areas on the measured surface are able to be handled without any compromise. Phase-shifted images are then captured at the calculated exposure times and a composite phase-shifted image is generated by extracting the optimally exposed pixels in the raw fringes images. For the second technique, it is proposed by introducing two orthogonal polarizers which are placed separately in front of the camera and projector into the first technique and the third one is developed by combining the second technique with the strategy of properly altering the angle between the transmission axes of the two polarizers. Experimental results show that the first technique can effectively improve the measurement accuracy of diffuse objects with LRR, the second one is capable of measuring object with weak specular reflection (WSR: e.g. shiny plastic surface) and the third can inspect surface with strong specular reflection (SSR: e.g. highlight on aluminum alloy) precisely. Further, more complex scene, such as the one with LRR and WSR, or even the one simultaneously involving LRR, WSR and SSR, can be measured accurately by the proposed solution.
NASA Astrophysics Data System (ADS)
Jelinek, H. J.
1986-01-01
This is the Final Report of Electronic Design Associates on its Phase I SBIR project. The purpose of this project is to develop a method for correcting helium speech, as experienced in diver-surface communication. The goal of the Phase I study was to design, prototype, and evaluate a real time helium speech corrector system based upon digital signal processing techniques. The general approach was to develop hardware (an IBM PC board) to digitize helium speech and software (a LAMBDA computer based simulation) to translate the speech. As planned in the study proposal, this initial prototype may now be used to assess expected performance from a self contained real time system which uses an identical algorithm. The Final Report details the work carried out to produce the prototype system. Four major project tasks were: a signal processing scheme for converting helium speech to normal sounding speech was generated. The signal processing scheme was simulated on a general purpose (LAMDA) computer. Actual helium speech was supplied to the simulation and the converted speech was generated. An IBM-PC based 14 bit data Input/Output board was designed and built. A bibliography of references on speech processing was generated.
The PAGES 2k Network, Phase 3: Themes and Call for Participation
NASA Astrophysics Data System (ADS)
von Gunten, L.; Mcgregor, H. V.; Martrat, B.; St George, S.; Neukom, R.; Bothe, O.; Linderholm, H. W.; Phipps, S. J.; Abram, N.
2017-12-01
The past 2000 years (the "2k" interval) provides critical context for understanding recent anthropogenic forcing of the climate and provides baseline information about the characteristics of natural climate variability. It also presents opportunities to improve the interpretation of proxy observations and to evaluate the climate models used to make future projections. Phases 1 and 2 of the PAGES 2k Network focussed on building regional and global surface temperature reconstructions for terrestrial regions and the oceans, and comparing these with model simulations to identify mechanisms of climate variation on interannual to bicentennial time scales. Phase 3 was launched in May 2017 and aims to address major questions around past hydroclimate, climate processes and proxy uncertainties. Its scientific themes are: Theme 1: "Climate Variability, Modes and Mechanisms"Further understand the mechanisms driving regional climate variability and change on interannual to centennial time scales; Theme 2: "Methods and Uncertainties"Reduce uncertainties in the interpretation of observations imprinted in paleoclimatic archives by environmental sensors; Theme 3: "Proxy and Model Understanding"Identify and analyse the extent of agreement between reconstructions and climate model simulations. Research is organized as a linked network of well-defined projects, identified and led by 2k community members. The 2k projects focus on specific scientific questions aligned with Phase 3 themes, rather than being defined along regional boundaries. New 2k projects can be proposed at any time at http://www.pastglobalchanges.org/ini/wg/2k-network/projects An enduring element of PAGES 2k is a culture of collegiality, transparency, and reciprocity. Phase 3 seeks to stimulate community based projects and facilitate collaboration between researchers from different regions and career stages, drawing on the breadth and depth of the global PAGES 2k community. All PAGES 2k projects also promote best practises in data stewardship for the research community. The network is open to anyone who is interested. If you would like to participate in PAGES 2k or receive updates, please join our mailing list or speak to a coordinating committee member.
NASA Technical Reports Server (NTRS)
Birchenough, Shawn; Kato, Denise; Kennedy, Fred; Akin, David
1990-01-01
The goals of Project Artemis are designed to meet the challege of President Bush to return to the Moon, this time to stay. The first goal of the project is to establish a permanent manned base on the Moon for the purposes of scientific research and technological development. The knowledge gained from the establishment and operations of the lunar base will then be used to achieve the second goal of Project Artemis, the establishment of a manned base on the Martian surface. Throughout both phases of the program, crew safety will be the number one priority. There are four main issues that have governed the entire program: crew safety and mission success, commonality, growth potential, and costing and scheduling. These issues are discussed in more detail.
Combining 3d Volume and Mesh Models for Representing Complicated Heritage Buildings
NASA Astrophysics Data System (ADS)
Tsai, F.; Chang, H.; Lin, Y.-W.
2017-08-01
This study developed a simple but effective strategy to combine 3D volume and mesh models for representing complicated heritage buildings and structures. The idea is to seamlessly integrate 3D parametric or polyhedral models and mesh-based digital surfaces to generate a hybrid 3D model that can take advantages of both modeling methods. The proposed hybrid model generation framework is separated into three phases. Firstly, after acquiring or generating 3D point clouds of the target, these 3D points are partitioned into different groups. Secondly, a parametric or polyhedral model of each group is generated based on plane and surface fitting algorithms to represent the basic structure of that region. A "bare-bones" model of the target can subsequently be constructed by connecting all 3D volume element models. In the third phase, the constructed bare-bones model is used as a mask to remove points enclosed by the bare-bones model from the original point clouds. The remaining points are then connected to form 3D surface mesh patches. The boundary points of each surface patch are identified and these boundary points are projected onto the surfaces of the bare-bones model. Finally, new meshes are created to connect the projected points and original mesh boundaries to integrate the mesh surfaces with the 3D volume model. The proposed method was applied to an open-source point cloud data set and point clouds of a local historical structure. Preliminary results indicated that the reconstructed hybrid models using the proposed method can retain both fundamental 3D volume characteristics and accurate geometric appearance with fine details. The reconstructed hybrid models can also be used to represent targets in different levels of detail according to user and system requirements in different applications.
Statistical models of lunar rocks and regolith
NASA Technical Reports Server (NTRS)
Marcus, A. H.
1973-01-01
The mathematical, statistical, and computational approaches used in the investigation of the interrelationship of lunar fragmental material, regolith, lunar rocks, and lunar craters are described. The first two phases of the work explored the sensitivity of the production model of fragmental material to mathematical assumptions, and then completed earlier studies on the survival of lunar surface rocks with respect to competing processes. The third phase combined earlier work into a detailed statistical analysis and probabilistic model of regolith formation by lithologically distinct layers, interpreted as modified crater ejecta blankets. The fourth phase of the work dealt with problems encountered in combining the results of the entire project into a comprehensive, multipurpose computer simulation model for the craters and regolith. Highlights of each phase of research are given.
Enhancing Functional Performance using Sensorimotor Adaptability Training Programs
NASA Technical Reports Server (NTRS)
Bloomberg, J. J.; Mulavara, A. P.; Peters, B. T.; Brady, R.; Audas, C.; Ruttley, T. M.; Cohen, H. S.
2009-01-01
During the acute phase of adaptation to novel gravitational environments, sensorimotor disturbances have the potential to disrupt the ability of astronauts to perform functional tasks. The goal of this project is to develop a sensorimotor adaptability (SA) training program designed to facilitate recovery of functional capabilities when astronauts transition to different gravitational environments. The project conducted a series of studies that investigated the efficacy of treadmill training combined with a variety of sensory challenges designed to increase adaptability including alterations in visual flow, body loading, and support surface stability.
Ultrasonic Waves in Water Visualized With Schlieren Imaging
NASA Technical Reports Server (NTRS)
Juergens, Jeffrey R.
2000-01-01
The Acoustic Liquid Manipulation project at the NASA Glenn Research Center at Lewis Field is working with high-intensity ultrasound waves to produce acoustic radiation pressure and acoustic streaming. These effects can be used to propel liquid flows to manipulate floating objects and liquid surfaces. Interest in acoustic liquid manipulation has been shown in acoustically enhanced circuit board electroplating, microelectromechanical systems (MEMS), and microgravity space experiments. The current areas of work on this project include phased-array ultrasonic beam steering, acoustic intensity measurements, and schlieren imaging of the ultrasonic waves.
Lead Paint Exposure Assessment in High Bays of Johnson Space Center
NASA Technical Reports Server (NTRS)
Stanch, Penney; Plaza, Angel; Keprta, Sean
2008-01-01
This slide presentation reviews the program to assess the possibility of lead paint exposure in the high bays of some of the Johnson Space Center buildings. Some of the buildings in the Manned Space Flight Center (MSC) were built in 1962 and predate any considerations to reduce lead in paints and coatings. There are many of these older buildings that contain open shops and work areas that have open ceilings, These shops include those that had operations that use leaded gasoline, batteries, and lead based paints. Test were planned to be conducted in three phases: (1) Surface Dust sampling, (2) personal exposure montioring, and (3) Ceiling paint Sampling. The results of the first two phases were reviewed. After considering the results of the first two phases, and the problems associated with the retrieval of samples from high ceilings, it was determined that the evaluation of ceiling coatings would be done on a project by project and in response to a complaint.
Dual-sensitivity profilometry with defocused projection of binary fringes.
Garnica, G; Padilla, M; Servin, M
2017-10-01
A dual-sensitivity profilometry technique based on defocused projection of binary fringes is presented. Here, two sets of fringe patterns with a sinusoidal profile are produced by applying the same analog low-pass filter (projector defocusing) to binary fringes with a high- and low-frequency spatial carrier. The high-frequency fringes have a binary square-wave profile, while the low-frequency binary fringes are produced with error-diffusion dithering. The binary nature of the binary fringes removes the need for calibration of the projector's nonlinear gamma. Working with high-frequency carrier fringes, we obtain a high-quality wrapped phase. On the other hand, working with low-frequency carrier fringes we found a lower-quality, nonwrapped phase map. The nonwrapped estimation is used as stepping stone for dual-sensitivity temporal phase unwrapping, extending the applicability of the technique to discontinuous (piecewise continuous) surfaces. We are proposing a single defocusing level for faster high- and low-frequency fringe data acquisition. The proposed technique is validated with experimental results.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-31
... scope of the action alternative which include acreage, water supply, and general site locations would... authorized boundary with a surface water supply as part of continued phased development of the CBP. The... alternative impacts considered in the Draft EIS. Two water supply options are being considered that would use...
Yunjun Yao; Shunlin Liang; Xianglan Li; Shaomin Liu; Jiquan Chen; Xiaotong Zhang; Kun Jia; Bo Jiang; Xianhong Xie; Simon Munier; Meng Liu; Jian Yu; Anders Lindroth; Andrej Varlagin; Antonio Raschi; Asko Noormets; Casimiro Pio; Georg Wohlfahrt; Ge Sun; Jean-Christophe Domec; Leonardo Montagnani; Magnus Lund; Moors Eddy; Peter D. Blanken; Thomas Grunwald; Sebastian Wolf; Vincenzo Magliulo
2016-01-01
The latent heat flux (LE) between the terrestrial biosphere and atmosphere is a major driver of the globalhydrological cycle. In this study, we evaluated LE simulations by 45 general circulation models (GCMs)in the Coupled Model Intercomparison Project Phase 5 (CMIP5) by a comparison...
360-degrees profilometry using strip-light projection coupled to Fourier phase-demodulation.
Servin, Manuel; Padilla, Moises; Garnica, Guillermo
2016-01-11
360 degrees (360°) digitalization of three dimensional (3D) solids using a projected light-strip is a well-established technique in academic and commercial profilometers. These profilometers project a light-strip over the digitizing solid while the solid is rotated a full revolution or 360-degrees. Then, a computer program typically extracts the centroid of this light-strip, and by triangulation one obtains the shape of the solid. Here instead of using intensity-based light-strip centroid estimation, we propose to use Fourier phase-demodulation for 360° solid digitalization. The advantage of Fourier demodulation over strip-centroid estimation is that the accuracy of phase-demodulation linearly-increases with the fringe density, while in strip-light the centroid-estimation errors are independent. Here we proposed first to construct a carrier-frequency fringe-pattern by closely adding the individual light-strip images recorded while the solid is being rotated. Next, this high-density fringe-pattern is phase-demodulated using the standard Fourier technique. To test the feasibility of this Fourier demodulation approach, we have digitized two solids with increasing topographic complexity: a Rubik's cube and a plastic model of a human-skull. According to our results, phase demodulation based on the Fourier technique is less noisy than triangulation based on centroid light-strip estimation. Moreover, Fourier demodulation also provides the amplitude of the analytic signal which is a valuable information for the visualization of surface details.
Early 20th Century Arctic Warming Intensified by Pacific and Atlantic Multidecadal Variability
NASA Astrophysics Data System (ADS)
Tokinaga, H.; Xie, S. P.; Mukougawa, H.
2017-12-01
We investigate the influence of Pacific and Atlantic multidecadal variability on the Arctic temperature, with a particular focus on the early 20th century Arctic warming. Arctic surface air temperature increased rapidly over the early 20th century, at rates comparable to those of recent decades despite much weaker greenhouse gas forcing than at present. We find that the concurrent phase shift of Pacific and Atlantic multidecadal variability is the major driver for the early 20th century Arctic warming. Atmospheric model simulations reproduce the early Arctic warming when the interdecadal variability of sea surface temperature (SST) is properly prescribed. The early Arctic warming is associated with the cold-to-warm phase shifts of Atlantic and Pacific multidecadal variability modes, a SST pattern reminiscent of the positive phase of the Pacific decadal and Atlantic multidecadal oscillations. The extratropical North Atlantic and North Pacific SST warming strengthens surface westerly winds over northern Eurasia, intensifying the warming there. The equatorial Pacific warming deepens the Aleutian low, advecting warm air to the North American Arctic. Coupled ocean-atmosphere simulations support the constructive intensification of Arctic warming by a concurrent, cold-to-warm phase shift of the Pacific and Atlantic multidecadal variability. Our results aid attributing the historical Arctic warming and thereby constrain the amplified warming projected for this important region.
NASA Astrophysics Data System (ADS)
Tada, Kohei; Koga, Hiroaki; Okumura, Mitsutaka; Tanaka, Shingo
2018-06-01
Spin contamination error in the total energy of the Au2/MgO system was estimated using the density functional theory/plane-wave scheme and approximate spin projection methods. This is the first investigation in which the errors in chemical phenomena on a periodic surface are estimated. The spin contamination error of the system was 0.06 eV. This value is smaller than that of the dissociation of Au2 in the gas phase (0.10 eV). This is because of the destabilization of the singlet spin state due to the weakening of the Au-Au interaction caused by the Au-MgO interaction.
Fission Surface Power Technology Development Update
NASA Technical Reports Server (NTRS)
Palac, Donald T.; Mason, Lee S.; Houts, Michael G.; Harlow, Scott
2011-01-01
Power is a critical consideration in planning exploration of the surfaces of the Moon, Mars, and places beyond. Nuclear power is an important option, especially for locations in the solar system where sunlight is limited or environmental conditions are challenging (e.g., extreme cold, dust storms). NASA and the Department of Energy are maintaining the option for fission surface power for the Moon and Mars by developing and demonstrating technology for a fission surface power system. The Fission Surface Power Systems project has focused on subscale component and subsystem demonstrations to address the feasibility of a low-risk, low-cost approach to space nuclear power for surface missions. Laboratory demonstrations of the liquid metal pump, reactor control drum drive, power conversion, heat rejection, and power management and distribution technologies have validated that the fundamental characteristics and performance of these components and subsystems are consistent with a Fission Surface Power preliminary reference concept. In addition, subscale versions of a non-nuclear reactor simulator, using electric resistance heating in place of the reactor fuel, have been built and operated with liquid metal sodium-potassium and helium/xenon gas heat transfer loops, demonstrating the viability of establishing system-level performance and characteristics of fission surface power technologies without requiring a nuclear reactor. While some component and subsystem testing will continue through 2011 and beyond, the results to date provide sufficient confidence to proceed with system level technology readiness demonstration. To demonstrate the system level readiness of fission surface power in an operationally relevant environment (the primary goal of the Fission Surface Power Systems project), a full scale, 1/4 power Technology Demonstration Unit (TDU) is under development. The TDU will consist of a non-nuclear reactor simulator, a sodium-potassium heat transfer loop, a power conversion unit with electrical controls, and a heat rejection system with a multi-panel radiator assembly. Testing is planned at the Glenn Research Center Vacuum Facility 6 starting in 2012, with vacuum and liquid-nitrogen cold walls to provide simulation of operationally relevant environments. A nominal two-year test campaign is planned including a Phase 1 reactor simulator and power conversion test followed by a Phase 2 integrated system test with radiator panel heat rejection. The testing is expected to demonstrate the readiness and availability of fission surface power as a viable power system option for NASA's exploration needs. In addition to surface power, technology development work within this project is also directly applicable to in-space fission power and propulsion systems.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Alexander, W.J.; Liddle, S.K.
1986-09-01
The primary objectives of this project were to collect and analyze groundwater, surface water, and sediment samples and to perform an initial characterization of the hydrogeochemical regime at potential contamination sites on Shaw Air Force Base near Sumter, South Carolina. This study constituted Phase II of the U.S. Air Force Installation Restoration Program (IRP). Five potential sources of groundwater pollution were studied. The evaluation primarily included the drilling of soil test borings, the installation, development, and sampling of groundwater monitoring wells, and the analyses of soil, surface water, and groundwater samples. Also used in the study were field measurements ofmore » water quality, water-level measurements site observations, published hydrogeologic data and Shaw AFB documents.« less
NASA Astrophysics Data System (ADS)
Price, G. J.; Marchant, T. E.; Parkhurst, J. M.; Sharrock, P. J.; Whitfield, G. A.; Moore, C. J.
2011-03-01
In image guided radiotherapy (IGRT) two of the most promising recent developments are four dimensional cone beam CT (4D CBCT) and dynamic optical metrology of patient surfaces. 4D CBCT is now becoming commercially available and finds use in treatment planning and verification, and whilst optical monitoring is a young technology, its ability to measure during treatment delivery without dose consequences has led to its uptake in many institutes. In this paper, we demonstrate the use of dynamic patient surfaces, simultaneously captured during CBCT acquisition using an optical sensor, to phase sort projection images for 4D CBCT volume reconstruction. The dual modality approach we describe means that in addition to 4D volumetric data, the system provides correlated wide field measurements of the patient's skin surface with high spatial and temporal resolution. As well as the value of such complementary data in verification and motion analysis studies, it introduces flexibility into the acquisition of the signal required for phase sorting. The specific technique used may be varied according to individual patient circumstances and the imaging target. We give details of three different methods of obtaining a suitable signal from the optical surfaces: simply following the motion of triangulation spots used to calibrate the surfaces' absolute height; monitoring the surface height in a single, arbitrarily selected, camera pixel; and tracking, in three dimensions, the movement of a surface feature. In addition to describing the system and methodology, we present initial results from a case study oesophageal cancer patient.
NASA Technical Reports Server (NTRS)
Hall, Edward; Magner, James
2011-01-01
This report is provided as part of ITT s NASA Glenn Research Center Aerospace Communication Systems Technical Support (ACSTS) contract NNC05CA85C, Task 7: New ATM Requirements-Future Communications, C-Band and L-Band Communications Standard Development and was based on direction provided by FAA project-level agreements for New ATM Requirements-Future Communications. Task 7 included two subtasks. Subtask 7-1 addressed C-band (5091- to 5150-MHz) airport surface data communications standards development, systems engineering, test bed and prototype development, and tests and demonstrations to establish operational capability for the Aeronautical Mobile Airport Communications System (AeroMACS). Subtask 7-2 focused on systems engineering and development support of the L-band digital aeronautical communications system (L-DACS). Subtask 7-1 consisted of two phases. Phase I included development of AeroMACS concepts of use, requirements, architecture, and initial high-level safety risk assessment. Phase II builds on Phase I results and is presented in two volumes. Volume I is devoted to concepts of use, system requirements, and architecture, including AeroMACS design considerations. Volume II (this document) describes an AeroMACS prototype evaluation and presents final AeroMACS recommendations. This report also describes airport categorization and channelization methodologies. The purposes of the airport categorization task were (1) to facilitate initial AeroMACS architecture designs and enable budgetary projections by creating a set of airport categories based on common airport characteristics and design objectives, and (2) to offer high-level guidance to potential AeroMACS technology and policy development sponsors and service providers. A channelization plan methodology was developed because a common global methodology is needed to assure seamless interoperability among diverse AeroMACS services potentially supplied by multiple service providers.
NASA Technical Reports Server (NTRS)
Hall, Edward; Isaacs, James; Henriksen, Steve; Zelkin, Natalie
2011-01-01
This report is provided as part of ITT s NASA Glenn Research Center Aerospace Communication Systems Technical Support (ACSTS) contract NNC05CA85C, Task 7: New ATM Requirements-Future Communications, C-Band and L-Band Communications Standard Development and was based on direction provided by FAA project-level agreements for New ATM Requirements-Future Communications. Task 7 included two subtasks. Subtask 7-1 addressed C-band (5091- to 5150-MHz) airport surface data communications standards development, systems engineering, test bed and prototype development, and tests and demonstrations to establish operational capability for the Aeronautical Mobile Airport Communications System (AeroMACS). Subtask 7-2 focused on systems engineering and development support of the L-band digital aeronautical communications system (L-DACS). Subtask 7-1 consisted of two phases. Phase I included development of AeroMACS concepts of use, requirements, architecture, and initial high-level safety risk assessment. Phase II builds on Phase I results and is presented in two volumes. Volume I (this document) is devoted to concepts of use, system requirements, and architecture, including AeroMACS design considerations. Volume II describes an AeroMACS prototype evaluation and presents final AeroMACS recommendations. This report also describes airport categorization and channelization methodologies. The purposes of the airport categorization task were (1) to facilitate initial AeroMACS architecture designs and enable budgetary projections by creating a set of airport categories based on common airport characteristics and design objectives, and (2) to offer high-level guidance to potential AeroMACS technology and policy development sponsors and service providers. A channelization plan methodology was developed because a common global methodology is needed to assure seamless interoperability among diverse AeroMACS services potentially supplied by multiple service providers.
NASA Astrophysics Data System (ADS)
Zhao, Yue; Zhu, Dianwen; Baikejiang, Reheman; Li, Changqing
2015-03-01
We have developed a new fluorescence molecular tomography (FMT) imaging system, in which we utilized a phase shifting method to extract the mouse surface geometry optically and a rotary laser scanning approach to excite fluorescence molecules and acquire fluorescent measurements on the whole mouse body. Nine fringe patterns with a phase shifting of 2π/9 are projected onto the mouse surface by a projector. The fringe patterns are captured using a webcam to calculate a phase map that is converted to the geometry of the mouse surface with our algorithms. We used a DigiWarp approach to warp a finite element mesh of a standard digital mouse to the measured mouse surface thus the tedious and time-consuming procedure from a point cloud to mesh is avoided. Experimental results indicated that the proposed method is accurate with errors less than 0.5 mm. In the FMT imaging system, the mouse is placed inside a conical mirror and scanned with a line pattern laser that is mounted on a rotation stage. After being reflected by the conical mirror, the emitted fluorescence photons travel through central hole of the rotation stage and the band pass filters in a motorized filter wheel, and are collected by a CCD camera. Phantom experimental results of the proposed new FMT imaging system can reconstruct the target accurately.
Novel Structured Metal Bipolar Plates for Low Cost Manufacturing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Conghua
2013-08-15
Bipolar plates are an important component in fuel cell stacks and accounts for more than 75% of stack weight and volume, and 20% of the stack cost. The technology development of metal bipolar plates can effectively reduce the fuel cells stack weight and volume over 50%. The challenge is to protect metal plate from corrosion at low cost for the broad commercial applications. While most of today’s PEM fuel cell metallic bipolar plate technologies use some precious metal, the focus of this SBIR project is to develop a low cost, novel nano-structured metal bipolar plate technology without using any preciousmore » metal. The technology will meet the performance and cost requirements for automobile applications. Through the Phase I project, TreadStone has identified the corrosion resistant and electrically conductive titanium oxide for the metal bipolar plate surface protection for automotive PEM fuel cell applications. TreadStone has overcome the manufacturing issues to apply the coating on metal substrate surface, and has demonstrated the feasibility of the coated stainless steel plates by ex-situ evaluation tests and the in-situ fuel cell long term durability test. The test results show the feasibility of the proposed nano-structured coating as the low cost metal bipolar plates of PEM fuel cells. The plan for further technology optimization is also outlined for the Phase II project.« less
Determining the location of buried plastic water pipes from measurements of ground surface vibration
NASA Astrophysics Data System (ADS)
Muggleton, J. M.; Brennan, M. J.; Gao, Y.
2011-09-01
‘Mapping the Underworld' is a UK-based project, which aims to create a multi-sensor device that combines complementary technologies for remote buried utility service detection and location. One of the technologies to be incorporated in the device is low-frequency vibro-acoustics, and techniques for detecting buried infrastructure, in particular plastic water pipes, are being investigated. One of the proposed techniques involves excitation of the pipe at some known location with concurrent vibrational mapping of the ground surface in order to infer the location of the remainder of the pipe. In this paper, measurements made on a dedicated pipe rig are reported. Frequency response measurements relating vibrational velocity on the ground to the input excitation were acquired. Contour plots of the unwrapped phase revealed the location of the pipe to within 0.1-0.2 m. Magnitude contour plots revealed the excitation point and also the location of the pipe end. By examining the unwrapped phase gradients along a line above the pipe, it was possible to identify the wave-type within the pipe responsible for the ground surface vibration. Furthermore, changes in the ground surface phase speed computed using this method enabled the location of the end of the pipe to be confirmed.
Novel Surface Modification Method for Ultrasupercritical Coal-Fired Boilers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Xiao, T. Danny
2013-05-22
US Department of Energy seeks an innovative coating technology for energy production to reduce the emission of SOx, NOx, and CO2 toxic gaseous species. To realize this need, Inframat Corporation (IMC) proposed an SPS thermal spray coating technique to produce ultrafine/nanocoatings that can be deposited onto the surfaces of high temperature boiler tubes, so that higher temperatures of boiler operation becomes possible, leading to significantly reduced emission of toxic gaseous species. It should be noted that the original PI was Dr. Xinqing Ma, who after 1.5 year conducting this project left Inframat in December, 2008. Thus, the PI was transferredmore » to Dr. Danny Xiao, who originally co-authored the proposal with Dr. Ma, in order to carry the project into a completion. Phase II Objectives: The proposed technology has the following attributes, including: (1). Dispersion of a nanoparticle or alloyed particle in a solvent to form a uniform slurry feedstock; (2). Feeding of the slurry feedstock into a thermal spray flame, followed by deposition of the slurry feedstock onto substrates to form tenacious nanocoatings; (3). High coating performance: including high bonding strength, and high temperature service life in the temperature range of 760oC/1400oF. Following the above premises, our past Phase I project has demonstrated the feasibility in small scale coatings on boiler substrates. The objective of this Phase II project was to focus on scale-up the already demonstrated Phase I work for the fabrication of SPS coatings that can satisfy DOE's emission reduction goals for energy production operations. Specifically, they are: (1). Solving engineering problems to scale-up the SPS-HVOF delivery system to a prototype production sub-delivery system; (2). Produce ultrafine/nanocoatings using the scale-up prototype system; (3). Demonstrate the coated components using the scale-up device having superior properties. Proposed Phase II Tasks: In the original Phase II proposal, we have six (6) technical tasks plus one (1) reporting task, as described below: Task 1 Scale-up and optimize the SPS process; Task 2 Coating design and fabrication with desired microstructure; Task 3 Evaluate microstructure and physical properties; Task 4 Test performance of long-term corrosion and erosion; Task 5 Test mechanical property and reliability; Task 6 Coating of a prototype boiler tube for evaluation; Task 7 Reporting task. To date, we have already completed all the technical tasks of 1 through 6. Major Phase II Achievements: In this four (4) year working period, Inframat had spent great effort to complete the proposed tasks. The project had been completed; the goals have been accomplished. Major achievements obtained include: (1). Developed a prototype scale-up slurry feedstock delivery system for thermal spray coatings; (2). Successfully coated high performance coatings using this scale-up slurry delivery system; (3). Commercial applications in energy efficiency and clean energy components have been developed using this newly fabricated slurry feedstock delivery system.« less
NASA Astrophysics Data System (ADS)
Shongwe, M.
2014-12-01
The warming rates projected by an ensemble of the Coupled Model Intercomparion Project Phase 5 (CMIP5) global climate models (GCMs) over southern Africa (south of 10 degrees latitude) are investigated. In all RCPs, CMIP5 models project a higher warming rate over the southwestern parts centred around the arid Kalahari and Namib deserts. The higher warming rates over these areas outpace global warming by up to a factor 2 in some GCMs. The projected warming is associated with an increase in heat waves. There is notable consensus across the models with little intermodel spread, suggesting a strong robustness of the projections. Mechanisms underlying the enhanced warming are investigated. A positive soil moisture-temperature feedback is suggested to contribute to the accelerated temperature increase. A decrease in soil moisture is projected by the GCMs over the area of highest warming. The reduction in soil wetness reduces evapotranspiration rates over the area where evaporation is dependent on available soil moisture. The reduction is evapotranspiration affects the partitioning of turbulent energy fluxes from the soil surface into the atmosphere and translates into an increase of the Bowen ratio featuring an increase in sensible relative to latent heat flux. An increase in sensible heat flux leads to an increase in near-surface temperature. The increase in temperature leads to a higher vapour pressure deficit and evaporative demand and evapotranspiration from the dry soils, possibly leading to a further decrease in soil moisture. A precipitation-soil moisture feedback is also suggested. A decrease in mean precipitation and an increase in drought conditions are projected over the area of enhanced warming. The reduced precipitation results in drier soils. The drier soil translates to reduced evapotranspiration for cloud and rainfall formation. However, the role played by the soil moisture-precipitation feedback loop is still inconclusive and characterized by some degree of uncertainty given that the strength of the local moisture recycling has not been explicitly quantified. An alternative mechanism involving the impact of soil moisture anomalies on boundary-layer stability and precipitation formation will be investigated.
Pressurized grout remote backfilling at AML sites near Beulah and Zap, North Dakota
DOE Office of Scientific and Technical Information (OSTI.GOV)
Weiner, E.J.; Dodd, W.E.
1999-07-01
The Abandoned Mine Lands (AML) Division of the North Dakota Public Service Commission (PSC) is charged with the reclamation of hazardous abandoned mine sites in North Dakota. Several underground lignite coalmines were operated near the cities of Beulah and Zap, North Dakota, from the early 1900's until about 1955. Coal seams in this area were relatively thick and the overburden generally shallow. As these mines have deteriorated with time, deep collapse features, or sinkholes, have surfaced in many areas. These features are very dangerous, especially when they occur at or near residential and commercial areas and public roads. In themore » past five years, sinkholes have surfaced beneath a commercial building (boat dealership, lounge, and gas station) and beneath a nearby occupied mobile home north of Beulah. sinkholes have also surfaced near KHOL Radio Station in Beulah and in the right of way of a public road south of Zap. The AML Division has conducted several emergency sinkhole-filling projects in these areas. In 1995--97, the AML Division conducted exploratory drilling which confirmed the presence of collapsing underground mines at these sites. The remediation of these sites around Beulah/Zap will take place over several years and involve three or more separate contracts due to budget considerations. In 1997, the AML Division began reclamation at these sties utilizing pressurized grout remote backfilling. In this technique, a cementitious grout is pumped through cased drill holes directly into the mine cavities to fill them and thereby stabilize the surface from collapse. The successful contractor for Phase One of the project was The Concrete Doctor, Inc. (TCDI). This paper will concentrate on Phase One of this work performed from June through September 1997. This project is especially interesting because grout was pumped through holes drilled inside the occupied commercial building. Grout was also pumped through angled holes that intercepted mined workings directly beneath the structure. Several specialized monitoring techniques were used to alert contractor if any movement in the structures occurred during grouting activities. Informational meetings were conducted by TCDI and PDC held with landowners, business owners, residents and road authorities before, during and after the project.« less
Microwave power transmitting phased array antenna research project
NASA Technical Reports Server (NTRS)
Dickinson, R. M.
1978-01-01
An initial design study and the development results of an S band RF power transmitting phased array antenna experiment system are presented. The array was to be designed, constructed and instrumented to permit wireless power transmission technology evaluation measurements. The planned measurements were to provide data relative to the achievable performance in the state of the art of flexible surface, retrodirective arrays, as a step in technically evaluating the satellite power system concept for importing to earth, via microwave beams, the nearly continuous solar power available in geosynchronous orbit. Details of the microwave power transmitting phased array design, instrumentation approaches, system block diagrams, and measured component and breadboard characteristics achieved are presented.
NASA Technical Reports Server (NTRS)
Morris, R. V.; Graff, T. G.; Achilles, C. N.; Agresti, D. G.; Ming, D. W.; Golden, D. C.
2011-01-01
Visible and near-IR (VNIR) spectra from the hyper-spectral imagers MRO-CRISM and Mars Express OMEGA in martian orbit have signatures from Fe-bearing phases (e.g., olivine, pyroxene, and jarosite), H2O/OH-bearing phases (e.g., smectites and other phyllosilicates, sulfates, and high-SiO2 phases), and carbonate [e.g., 1-5]. Mineralogical assignments of martian spectral features are made on the basis of VNIR spectra acquired in the laboratory under appropriate environmental conditions on samples whose mineralogical composition is known. We report here additional results for our ongoing project [6] to acquire VNIR spectra under arid conditions.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ivashchenko, I.A., E-mail: inna.ivashchenko@mail.ru; Danyliuk, I.V.; Olekseyuk, I.D.
2014-02-15
The quasi-ternary system Ag{sub 2}Se–Ga{sub 2}Se{sub 3}–In{sub 2}Se{sub 3} was investigated by differential thermal, X-ray phase, X-ray structure, microstructure analysis and microhardness measurements. Five quasi-binary phase diagrams, six polythermal sections, isothermal section at 820 K and the liquidus surface projection were constructed. The character and temperature of the invariant processes were determined. The specific resistance of the single crystals (Ga{sub 0.6}In{sub 0.4}){sub 2}Se{sub 3}, (Ga{sub 0.594}In{sub 0.396}Er{sub 0.01}){sub 2}Se{sub 3} was measured, 7.5×10{sup 5} and 3.15×10{sup 5} Ω m, respectively, optical absorption spectra in the 600–1050 nm range were recorded at room temperature, and the band gap energy was estimatedmore » which is 1.95±0. 01 eV for both samples. - Graphical abstract: The article reports for the first time the investigated liquidus surface projection of the Ag{sub 2}Se–Ga{sub 2}Se{sub 3}–In{sub 2}Se{sub 3} system and isothermal section at 820 K of the system. Five phase diagrams, six polythermal sections, isothermal section at 820 K and the liquidus surface projection were built at the first time. The existence of the large region of the solid solutions based on AgIn{sub 5}Se{sub 8}, Ga{sub 2}Se{sub 3} and AgGa{sub 1−x}In{sub x}Se{sub 2} was investigated. The existence of two ternary phases was established in the Ga{sub 2}Se{sub 3}–In{sub 2}Se{sub 3} system. Two single crystals (Ga{sub 0.6}In{sub 0.4}){sub 2}Se{sub 3}, (Ga{sub 0.594}In{sub 0.396}Er{sub 0.01}){sub 2}Se{sub 3} were grown and some of optical properties of them were studied at first time. Display Omitted - Highlights: • Liquidus surface projection was built for Ag{sub 2}Se–Ga{sub 2}Se{sub 3}–In{sub 2}Se{sub 3} system. • Solid solution ranges of AgIn{sub 5}Se{sub 8}, Ga{sub 2}Se{sub 3} and AgGa{sub 1−x}In{sub x}Se{sub 2} were investigated. • Two single crystals (Ga{sub 0.6}In{sub 0.4}){sub 2}Se{sub 3}, (Ga{sub 0.594}In{sub 0.396}Er{sub 0.01}){sub 2}Se{sub 3} were grown. • Some optical properties of these single crystals were studied.« less
Optimum projection pattern generation for grey-level coded structured light illumination systems
NASA Astrophysics Data System (ADS)
Porras-Aguilar, Rosario; Falaggis, Konstantinos; Ramos-Garcia, Ruben
2017-04-01
Structured light illumination (SLI) systems are well-established optical inspection techniques for noncontact 3D surface measurements. A common technique is multi-frequency sinusoidal SLI that obtains the phase map at various fringe periods in order to estimate the absolute phase, and hence, the 3D surface information. Nevertheless, multi-frequency SLI systems employ multiple measurement planes (e.g. four phase shifted frames) to obtain the phase at a given fringe period. It is therefore an age old challenge to obtain the absolute surface information using fewer measurement frames. Grey level (GL) coding techniques have been developed as an attempt to reduce the number of planes needed, because a spatio-temporal GL sequence employing p discrete grey-levels and m frames has the potential to unwrap up to pm fringes. Nevertheless, one major disadvantage of GL based SLI techniques is that there are often errors near the border of each stripe, because an ideal stepwise intensity change cannot be measured. If the step-change in intensity is a single discrete grey-level unit, this problem can usually be overcome by applying an appropriate threshold. However, severe errors occur if the intensity change at the border of the stripe exceeds several discrete grey-level units. In this work, an optimum GL based technique is presented that generates a series of projection patterns with a minimal gradient in the intensity. It is shown that when using this technique, the errors near the border of the stripes can be significantly reduced. This improvement is achieved with the choice generated patterns, and does not involve additional hardware or special post-processing techniques. The performance of that method is validated using both simulations and experiments. The reported technique is generic, works with an arbitrary number of frames, and can employ an arbitrary number of grey-levels.
PowerSat: A technology demonstration of a solar power satellite
NASA Technical Reports Server (NTRS)
Sigler, Douglas L. (Editor); Riedman, John; Duracinski, Jon; Edwards, Joe; Brown, Garry; Webb, Ron; Platzke, Mike; Yuan, Xiaolin; Rogers, Pete; Khan, Afsar
1994-01-01
PowerSat is a preliminary design strategy for microwave wireless power transfer of solar energy. Solar power satellites convert solar power into microwave energy and use wireless power transmission to transfer the power to the Earth's surface. The PowerSat project will show how new developments in inflatable technology can be used to deploy solar panels and phased array antennas.
USDA-ARS?s Scientific Manuscript database
Improving process-based crop models is needed to achieve high fidelity forecasts of regional energy, water, and carbon exchange. However, most state-of-the-art Land Surface Models (LSMs) assessed in the fifth phase of the Coupled Model Inter-comparison project (CMIP5) simulated crops as simple C3 or...
Performance modelling of miniaturized flash-imaging lidars for future mars exploration missions
NASA Astrophysics Data System (ADS)
Mitev, V.; Pollini, A.; Haesler, J.; Pereira do Carmo, João.
2017-11-01
Future planetary exploration missions require the support of 3D vision in the GN&C during key spacecraft's proximity phases, namely: i) spacecraft precision and soft Landing on the planet's surface; ii) Rendezvous and Docking (RVD) between a Sample Canister (SC) and an orbiter spacecraft; iii) Rover Navigation (RN) on planetary surface. The imaging LiDARs are among the best candidate for such tasks [1-3]. The combination of measurement requirements and environmental conditions seems to find its optimum in the flash 3D LiDAR architecture. Here we present key steps is the evaluation of novelty light detectors and MOEMS (Micro-Opto- Electro-Mechanical Systems) technologies with respect to LiDAR system performance and miniaturization. The objectives of the project MILS (Miniaturized Imaging LiDAR System, Phase 1) concentrated on the evaluation of novel detection and scanning technologies for the miniaturization of 3D LiDARs intended for planetary mission. Preliminary designs for an elegant breadboard (EBB) for the three tasks stated above (Landing, RVD and RN) were proposed, based on results obtained with a numerical model developed in the project and providing the performances evaluation of imaging LiDARs.
Digital fringe projection for hand surface coordinate variation analysis caused by osteoarthritis
NASA Astrophysics Data System (ADS)
Nor Haimi, Wan Mokhdzani Wan; Hau Tan, Cheek; Retnasamy, Vithyacharan; Vairavan, Rajendaran; Sauli, Zaliman; Roshidah Yusof, Nor; Hambali, Nor Azura Malini Ahmad; Aziz, Muhammad Hafiz Ab; Bakhit, Ahmad Syahir Ahmad
2017-11-01
Hand osteoarthritis is one of the most common forms of arthritis which impact millions of people worldwide. The disabling problem occurs when the protective cartilage on the boundaries of bones wear off over time. Currently, in order to identify hand osteoarthritis, special instruments namely X-ray scanning and MRI are used for the detection but it also has its limitations such as radiation exposure and can be quite costly. In this work, an optical metrology system based on digital fringe projection which comprises of an LCD projector, CCD camera and a personal computer has been developed to anticipate abnormal growth or deformation on the joints of the hand which are common symptoms of osteoarthritis. The main concept of this optical metrology system is to apply structured light as imaging source for surface change detection. The imaging source utilizes fringe patterns generated by C++ programming and is shifted by 3 phase shifts based on the 3 steps 2 shifts method. Phase wrapping technique and analysis were applied in order to detect the deformation of live subjects. The result has demonstrated a successful method of hand deformation detection based on the pixel tracking differences of a normal and deformed state.
NASA Astrophysics Data System (ADS)
Foglia, L.; Rossetto, R.; Borsi, I.; Josef, S.; Boukalova, Z.; Triana, F.; Ghetta, M.; Sabbatini, T.; Bonari, E.; Cannata, M.; De Filippis, G.
2016-12-01
The EU H2020 FREEWAT project (FREE and open source software tools for WATer resource management) aims at simplifying the application of EU-water related Directives, by developing an open source and public domain, GIS-integrated platform for planning and management of ground- and surface-water resources. The FREEWAT platform is conceived as a canvas, where several distributed and physically-based simulation codes are virtually integrated. The choice of such codes was supported by the result of a survey performed by means of questionnaires distributed to 14 case study FREEWAT project partners and several stakeholders. This was performed in the first phase of the project within the WP 6 (Enhanced science and participatory approach evidence-based decision making), Task 6.1 (Definition of a "needs/tools" evaluation grid). About 30% among all the invited entities and institutions from several EU and non-EU Countries expressed their interest in contributing to the survey. Most of them were research institutions, government and geoenvironmental companies and river basin authorities.The result of the questionnaire provided a spectrum of needs and priorities of partners/stakeholders, which were addressed during the development phase of the FREEWAT platform. The main needs identified were related to ground- and surface-water quality, sustainable water management, interaction between groundwater/surface-water bodies, and design and management of Managed Aquifer Recharge schemes. Needs and priorities were then connected to the specific EU Directives and Regulations to be addressed.One of the main goals of the questionnaires was to collect information and suggestions regarding the use of existing commercial/open-source software tools to address needs and priorities, and regarding the needs to address specific water-related processes/problems.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Xiang, Baoqiang; Zhao, Ming; Held, Isaac M.
The severity of the double Intertropical Convergence Zone (DI) problem in climate models can be measured by a tropical precipitation asymmetry index (PAI), indicating whether tropical precipitation favors the Northern Hemisphere or the Southern Hemisphere. Examination of 19 Coupled Model Intercomparison Project phase 5 models reveals that the PAI is tightly linked to the tropical sea surface temperature (SST) bias. As one of the factors determining the SST bias, the asymmetry of tropical net surface heat flux in Atmospheric Model Intercomparison Project (AMIP) simulations is identified as a skillful predictor of the PAI change from an AMIP to a coupledmore » simulation, with an intermodel correlation of 0.90. Using tropical top-of-atmosphere (TOA) fluxes, the correlations are lower but still strong. However, the extratropical asymmetries of surface and TOA fluxes in AMIP simulations cannot serve as useful predictors of the PAI change. Furthermore, this study suggests that the largest source of the DI bias is from the tropics and from atmospheric models.« less
NASA Astrophysics Data System (ADS)
Teller, Amit; Lange, Manfred; Ioannou, Stelios; Keleshis, Christos
2010-05-01
The Autonomous Flying Platforms for Atmospheric and Earth Surface Observations project (APAESO) of the Energy, Environment and Water Research Center (EEWRC) at the Cyprus Institute is aimed at the dual purpose of carrying out atmospheric and earth-surface observations in the Mediterranean. The APAESO platforms will offer the unique potential to determine physical, chemical and radiative atmospheric properties, aerosol and dust concentrations, atmospheric dynamics, surface morphology, vegetation and land use patterns as well as ocean surface properties (biology, waves, currents) and to carry out archaeological site reconnaissance and contaminant detection at high spatial resolution. The first phase of APAESO was dedicated to the preliminary design and the selection of an Unmanned Aerial Vehicle (UAV) as the backbone of the APAESO infrastructure. Selection of a UAV suitable for the many research objectives as outlined above is challenging because the UAV technology is new and rapidly evolving. This notwithstanding, a very large number of systems, mostly utilized for defense purposes, are currently available. The major challenge in the selection process lies in considering the trade-off between different platform characteristics (e.g. payload weight, endurance, max. altitude for operation and price) and in optimizing the potential performance of the UAV. Based on the required characteristics for the UAV platform, a survey of possible UAVs and suitable sensors was prepared based on various data sources. We used an elimination process in order to consider only a few models for the final selection process out of about 1000 commercially available UAV models that were initially investigated. The presentation will discuss the main scientific objectives that determine the specification of the UAV platform, major considerations in selecting best available technology for our needs and will briefly describe the next phases of the project.
The dynamical properties of a Rydberg hydrogen atom between two parallel metal surfaces
NASA Astrophysics Data System (ADS)
Liu, Wei; Li, Hong-Yun; Yang, Shan-Ying; Lin, Sheng-Lu
2011-03-01
This paper presents the dynamical properties of a Rydberg hydrogen atom between two metal surfaces using phase space analysis methods. The dynamical behaviour of the excited hydrogen atom depends sensitively on the atom—surface distance d. There exists a critical atom—surface distance dc = 1586 a.u. When the atom—surface distance d is larger than the critical distance dc, the image charge potential is less important than the Coulomb potential, the system is near-integrable and the electron motion is regular. As the distance d decreases, the system will tend to be non-integrable and unstable, and the electron might be captured by the metal surfaces. Project supported by the National Natural Science Foundation of China (Grant No. 10774093) and the Natural Science Foundation of Shandong Province (Grant No. ZR2009FZ006).
Low-energy electron diffraction study of Si(111)-(√3x √3)R30∘ -B
NASA Astrophysics Data System (ADS)
Marino, K. E.; Huang, Y. T.; Diehl, R. D.; Tu, Weison; Mulugeta, Daniel; Snijders, P. C.; Weitering, H. H.
2014-03-01
Metal-semiconductor interfaces are important for the function and manufacture of advanced electronics, such as those used in computers, tablets and phones. They also exhibit many interesting physical phenomena that are interesting from a fundamental point of view, including exotic phases and phase transitions. This study involves the analysis and modeling of the surface structure of a thin film of boron on the Si(111) surface. The addition of metal atoms to the surface of Si(111) simplifies its structure by removing a ``rippling'' that is present on the clean surface. The low-energy electron diffraction (LEED) data were measured at a surface temperature of 80 K at ORNL. The LEED analysis utilized the SATLEED analysis programs. The results are similar to those obtained in an earlier LEED study for this interface, but the precision is higher due to the larger dataset employed., The results of this study will be compared to other studies of this and similar systems. We acknowledge the Eberly College of Science for funding this project. González, Guo, Ortega, Flores, Weitering. Phys. Rev. Lett. 102, 115501 (2009)
Atmospheric surface and boundary layers of the Amazon Basin
NASA Technical Reports Server (NTRS)
Garstang, Michael
1987-01-01
Three phases of work were performed: design of and preparation for the Amazon Boundary Layer Experiment (ABLE 2-A); execution of the ABLE 2-A field program; and analysis of the ABLE 2-A data. Three areas of experiment design were dealt with: surface based meteorological measurements; aircraft missions; and project meteorological support. The primary goal was to obtain a good description of the structure of the atmosphere immediately above the rain forest canopy (top of canopy to a few thousand meters), to describe this region during the growing daytime phase of the boundary layer; and to examine the nighttime stratified state. A secondary objective was to examine the role that deep convective storms play in the vertical transport of heat, water vapor, and other trace gases. While significant progress was made, much of the analysis remains to be done.
INDUSTRIAL AND SCIENTIFIC APPLICATIONS OF NUCLEAR EXPLOSIONS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Johnson, Gerald W.
1960-01-19
ABS>Information is given for a series of underground and surface nuclear explosions ranging from 0.055 to 19 kilotons in size. A model of four stages is developed and applied to the case of the Rainier explosion: (1) Nuclear Reaction, microsecond range. (2) Hydrodynamic Phase, millisecond range. (3) Quasi-Static Phase, secondminute range. (4) Longer-Term Phase, minute-year range. Data are given for the growth rate of the Rainier cavity up to 75 msec, partition of energy in the second stage, and distribution of temperature 5 months after the Rainier explosion. The following generalizations were made for tuff soil: Radioactivity can be containedmore » completely underground at depths of D = 400 W/sup 1/3/ or greater, where W is the energy release in kilotons; the cavity initially formed has a radius of R = 50 W/sup 1/3/; and 65 to 80% of the fission-product activity is in dilute (0.1 ppm) glass solution. The purpose and scheme of the three current AEC projects, Gnome, Project Oil Sand, and Project Chariot, are given. Also, some experiments to be done with nuclear explosions are suggested for space research, production of transplutonic isotopes, neutron resonance, other cross sections, earth's structure, and seismology. (D.L.C.)« less
NASA Astrophysics Data System (ADS)
Fan, W.; Shearer, P. M.
2017-12-01
Fan and Shearer [2016] analyzed the 2012 Mw 7.2 Sumatra earthquake and reported that the earthquake dynamically triggered early aftershock/aftershocks 150 km away from the mainshock and 50 s later. The early aftershock/aftershocks were detected with teleseismic P-wave back-projection, coincided with passing surface waves, and showed observable seismic waveforms in a wide frequency range (0.02—5 Hz). Recently, however, Yue et al. [2017] interpreted these coda arrivals as water reverberations from the mainshock, based mostly on EGF analysis of a nearby M6 earthquake and a water-phase synthetic test. Here, we show detailed back-projection and waveform analysis of three M6 earthquakes within 100km of the Mw 7.2 earthquake, including the EGF event analyzed in Yue et al. [2017]. In addition, we examine the waveforms of three M5.5 reverse faulting earthquakes close to our detected early aftershock landward of the trench. Our results show that the coda energy in question is more likely caused by a separate earthquake near the trench than by a mainshock water reverberation phase, thus supporting our earlier conclusion that the detected coherent radiators are likely to be dynamically triggered early aftershock/aftershocks.
NASA Astrophysics Data System (ADS)
Stoykova, Elena; Gotchev, Atanas; Sainov, Ventseslav
2011-01-01
Real-time accomplishment of a phase-shifting profilometry through simultaneous projection and recording of fringe patterns requires a reliable phase retrieval procedure. In the present work we consider a four-wavelength multi-camera system with four sinusoidal phase gratings for pattern projection that implements a four-step algorithm. Successful operation of the system depends on overcoming two challenges which stem out from the inherent limitations of the phase-shifting algorithm, namely the demand for a sinusoidal fringe profile and the necessity to ensure equal background and contrast of fringes in the recorded fringe patterns. As a first task, we analyze the systematic errors due to the combined influence of the higher harmonics and multi-wavelength illumination in the Fresnel diffraction zone considering the case when the modulation parameters of the four gratings are different. As a second task we simulate the system performance to evaluate the degrading effect of the speckle noise and the spatially varying fringe modulation at non-uniform illumination on the overall accuracy of the profilometric measurement. We consider the case of non-correlated speckle realizations in the recorded fringe patterns due to four-wavelength illumination. Finally, we apply a phase retrieval procedure which includes normalization, background removal and denoising of the recorded fringe patterns to both simulated and measured data obtained for a dome surface.
Refining the Tonga Slab Geometry Using Slab Phases of Seismic Waves
NASA Astrophysics Data System (ADS)
Alongi, T.; Wei, S. S.; Blackman, D. K.
2017-12-01
Although the Tonga subducting slab geometry has been previously mapped by earthquake distribution, its detailed morphology is poorly constrained. The uncertainties of the slab surface relative to earthquakes can be translated into large errors in predicted temperature of hypocenters that is considered as a chief control of intermediate-depth seismicity. Seismic waves converted at the interface between the slab crust and the overlying mantle wedge can provide additional constraints on the location of the slab surface. A PS phase converted at the slab interface is observable in the horizontal components, whereas an SP converted phase can be seen in the vertical component. In this study, we analyze PS and SP phases in the seismic dataset of the 2009-2010 Ridge2000 Lau Spreading Center project, which consisted of 50 ocean bottom seismographs (OBSs) and 17 island-based seismic stations deployed in Fiji, Tonga, and the Lau Basin for about one year. More than 1,000 PS arrivals from local events were manually picked, predominantly with a 1-3 Hz filter. Next, the PS-P differential travel times will be inverted to determine improved depths of the slab surface relative to the local earthquakes and the receiving stations. The refined slab geometry will allow us to assess the thermal structure and dehydration reactions of the Tonga slab, lending further insight into the mechanisms of intermediate-depth seismicity.
Asteroid exploration and utilization
NASA Technical Reports Server (NTRS)
Radovich, Brian M.; Carlson, Alan E.; Date, Medha D.; Duarte, Manny G.; Erian, Neil F.; Gafka, George K.; Kappler, Peter H.; Patano, Scott J.; Perez, Martin; Ponce, Edgar
1992-01-01
The Earth is nearing depletion of its natural resources at a time when human beings are rapidly expanding the frontiers of space. The resources possessed by asteroids have enormous potential for aiding and enhancing human space exploration as well as life on Earth. Project STONER (Systematic Transfer of Near Earth Resources) is based on mining an asteroid and transporting raw materials back to Earth. The asteroid explorer/sample return mission is designed in the context of both scenarios and is the first phase of a long range plan for humans to utilize asteroid resources. Project STONER is divided into two parts: asteroid selection and explorer spacecraft design. The spacecraft design team is responsible for the selection and integration of the subsystems: GNC, communications, automation, propulsion, power, structures, thermal systems, scientific instruments, and mechanisms used on the surface to retrieve and store asteroid regolith. The sample return mission scenario consists of eight primary phases that are critical to the mission.
The PAGES 2k Network, Phase 3: Introduction, Goals and Call for Participation
NASA Astrophysics Data System (ADS)
McGregor, Helen; Phipps, Steven; von Gunten, Lucien; Martrat, Belen; Linderholm, Lars; Abram, Nerilie; Bothe, Oliver; Neukom, Raphael; St. George, Scott; Evans, Michael; Kaufman, Darrell; Goosse, Hugues; Turney, Chris
2017-04-01
The past 2000 years (the "2k" interval) provides critical context for recent anthropogenic forcing of the climate, baseline information about Earth's natural climate variability, opportunities to improve the interpretation of proxy observations, and evaluation of climate models. The PAGES 2k Network (2008-2013 Phase 1; 2014-2016 Phase 2) built regional and global surface temperature reconstructions for terrestrial regions and the oceans, and used comparison with realistically forced simulations to identify mechanisms of climate variation on interannual to bicentennial time scales. The goals of Phase 3 (2017-2019), which launches in May 2017 at the PAGES Open Science Meeting, are to: 1) Further understand the mechanisms driving regional climate variability and change on interannual to centennial time scales (Theme: "Climate Variability, Modes and Mechanisms"); 2) Reduce uncertainties in the interpretation of observations imprinted in paleoclimatic archives by environmental sensors (Theme: "Methods and Uncertainties"); and 3) Identify and analyse the extent of agreement between reconstructions and climate model simulations (Theme: "Proxy and Model Understanding") Research will be organized as a linked network of well-defined projects and targeted manuscripts, identified and led by 2k members. The 2k projects will focus on specific scientific questions aligned with Phase 3 goals, rather than being defined along regional boundaries. An enduring element from earlier phases of PAGES 2k will be a culture of collegiality, transparency, and reciprocity. Phase 3 seeks to stimulate community based projects and facilitate collaboration of researchers from different regions and career stages, drawing on breadth and depth of the global PAGES 2k community; support end-to-end workflow transparency and open data and knowledge access; and develop collaborations with other research communities and engage with stakeholders. If you would like to participate in PAGES 2k Phase 3 or receive updates, please join our mailing list, or speak to a coordinating committee member.
Moire technique utilization for detection and measurement of scoliosis
NASA Astrophysics Data System (ADS)
Zawieska, Dorota; Podlasiak, Piotr
1993-02-01
Moire projection method enables non-contact measurement of the shape or deformation of different surfaces and constructions by fringe pattern analysis. The fringe map acquisition of the whole surface of the object under test is one of the main advantages compared with 'point by point' methods. The computer analyzes the shape of the whole surface and next user can selected different points or cross section of the object map. In this paper a few typical examples of an application of the moire technique in solving different medical problems will be presented. We will also present to you the equipment the moire pattern analysis is done in real time using the phase stepping method with CCD camera.
Intermediate Experimental Vehicle (IXV): Avionics and Software of the ESA Reentry Demonstrator
NASA Astrophysics Data System (ADS)
Malucchi, Giovanni; Dussy, Stephane; Camuffo, Fabrizio
2012-08-01
The IXV project is conceived as a technology platform that would perform the step forward with respect to the Atmospheric Reentry Demonstrator (ARD), by increasing the system maneuverability and verifying the critical technology performances against a wider re- entry corridor.The main objective is to design, develop and to perform an in-flight verification of an autonomous lifting and aerodynamically controlled (by a combined use of thrusters and aerodynamic surfaces) reentry system.The project also includes the verification and experimentation of a set of critical reentry technologies and disciplines:Thermal Protection System (TPS), for verification and characterization of thermal protection technologies in representative operational environment;Aerodynamics - Aerthermodynamics (AED-A TD), for understanding and validation of aerodynamics and aerothermodyamics phenomena with improvement of design tools;Guidance, Navigation and Control (GNC), for verification of guidance, navigation and control techniques in representative operational environment (i.e. reentry from Low Earth Orbit);Flight dynamics, to update and validate the vehicle model during actual flight, focused on stability and control derivatives.The above activities are being performed through the implementation of a strict system design-to-cost approach with a proto-flight model development philosophy.In 2008 and 2009, the IXV project activities reached the successful completion of the project Phase-B, including the System PDR, and early project Phase-C.In 2010, following a re-organization of the industrial consortium, the IXV project successfully completed a design consolidation leading to an optimization of the technical baseline including the GNC, avionics (i.e. power, data handling, radio frequency and telemetry), measurement sensors, hot and cold composite structures, thermal protections and control, with significant improvements of the main system budgets.The project has successfully closed the System CDR during 2011 and it is currently running the Phase-D with the target to be launched with Vega from Kourou in 2014The paper will provide an overview of the IXV design and mission objectives in the frame of the atmospheric reentry overall activities, focusing on the avionics and software architecture and design.
Accurate Theoretical Predictions of the Properties of Energetic Materials
2008-09-18
decomposition, Monte Carlo, molecular dynamics, supercritical fluids, solvation and separation, quantum Monte Carlo, potential energy surfaces, RDX , TNAZ...labs, who are contributing to the theoretical efforts, providing data for testing of the models, or aiding in the transition of the methods, models...and results to DoD applications. The major goals of the project are: • Models that describe phase transitions and chemical reactions in
40 CFR 35.1650-3 - Conditions on award.
Code of Federal Regulations, 2011 CFR
2011-07-01
... non-Federal share of the project costs. (b) Phase 1. Phase 1 projects are subject to the following conditions: (1) The recipient must receive EPA project officer approval on any changes to satisfy the... additional work under the project. (c) Phase 2. Phase 2 projects are subject to the following conditions: (1...
40 CFR 35.1650-3 - Conditions on award.
Code of Federal Regulations, 2010 CFR
2010-07-01
... non-Federal share of the project costs. (b) Phase 1. Phase 1 projects are subject to the following conditions: (1) The recipient must receive EPA project officer approval on any changes to satisfy the... additional work under the project. (c) Phase 2. Phase 2 projects are subject to the following conditions: (1...
40 CFR 35.1650-3 - Conditions on award.
Code of Federal Regulations, 2014 CFR
2014-07-01
... non-Federal share of the project costs. (b) Phase 1. Phase 1 projects are subject to the following conditions: (1) The recipient must receive EPA project officer approval on any changes to satisfy the... additional work under the project. (c) Phase 2. Phase 2 projects are subject to the following conditions: (1...
40 CFR 35.1650-3 - Conditions on award.
Code of Federal Regulations, 2012 CFR
2012-07-01
... non-Federal share of the project costs. (b) Phase 1. Phase 1 projects are subject to the following conditions: (1) The recipient must receive EPA project officer approval on any changes to satisfy the... additional work under the project. (c) Phase 2. Phase 2 projects are subject to the following conditions: (1...
40 CFR 35.1650-3 - Conditions on award.
Code of Federal Regulations, 2013 CFR
2013-07-01
... non-Federal share of the project costs. (b) Phase 1. Phase 1 projects are subject to the following conditions: (1) The recipient must receive EPA project officer approval on any changes to satisfy the... additional work under the project. (c) Phase 2. Phase 2 projects are subject to the following conditions: (1...
NASA Astrophysics Data System (ADS)
Zhu, X.
2017-12-01
Based on methods of statistical analysis, the time series of global surface air temperature(SAT) anomalies from 1860-2014 has been defined by three types of phase changes that occur through the division of temperature changes into different stages. The characteristics of the three types of phase changes simulated by CMIP5 models were evaluated. The conclusion is as follows: the SAT from 1860-2014 can be divided into six stages according to trend differences, and this subdivision is proved to be statistically significant. Based on trend analysis and the distribution of slopes between any two points (two points' slope) in every stage, the six stages can be summarized as three phase changes of warming, cooling, and hiatus. Between 1860 and 2014, the world experienced three heating phases (1860-1878, 1909-1942,1975-2004), one cooling phase (1878-1909), and two hiatus phases (1942-1975, 2004-2014).Using the definition method, whether the next year belongs to the previous phase can be estimated. Furthermore, the temperature in 2015 was used as an example to validate the feasibility of this method. The simulations of the heating period by CMIP5 models are well; however the characteristics shown by SAT during the cooling and hiatus period cannot be represented by CMIP5 models. As such, the projections of future heating phases using the CMIP5 models are credible, but for cooling and hiatus events they are unreliable.
Feasibility Study of Commercial Markets for New Sample Acquisition Devices
NASA Technical Reports Server (NTRS)
Brady, Collin; Coyne, Jim; Bilen, Sven G.; Kisenwether, Liz; Miller, Garry; Mueller, Robert P.; Zacny, Kris
2010-01-01
The NASA Exploration Systems Mission Directorate (ESMD) and Penn State technology commercialization project was designed to assist in the maturation of a NASA SBIR Phase III technology. The project was funded by NASA's ESMD Education group with oversight from the Surface Systems Office at NASA Kennedy Space Center in the Engineering Directorate. Two Penn State engineering student interns managed the project with support from Honeybee Robotics and NASA Kennedy Space Center. The objective was to find an opportunity to integrate SBIR-developed Regolith Extractor and Sampling Technology as the payload for the future Lunar Lander or Rover missions. The team was able to identify two potential Google Lunar X Prize organizations with considerable interest in utilizing regolith acquisition and transfer technology.
Local blur analysis and phase error correction method for fringe projection profilometry systems.
Rao, Li; Da, Feipeng
2018-05-20
We introduce a flexible error correction method for fringe projection profilometry (FPP) systems in the presence of local blur phenomenon. Local blur caused by global light transport such as camera defocus, projector defocus, and subsurface scattering will cause significant systematic errors in FPP systems. Previous methods, which adopt high-frequency patterns to separate the direct and global components, fail when the global light phenomenon occurs locally. In this paper, the influence of local blur on phase quality is thoroughly analyzed, and a concise error correction method is proposed to compensate the phase errors. For defocus phenomenon, this method can be directly applied. With the aid of spatially varying point spread functions and local frontal plane assumption, experiments show that the proposed method can effectively alleviate the system errors and improve the final reconstruction accuracy in various scenes. For a subsurface scattering scenario, if the translucent object is dominated by multiple scattering, the proposed method can also be applied to correct systematic errors once the bidirectional scattering-surface reflectance distribution function of the object material is measured.
High pressure cosmochemistry applied to major planetary interiors: Experimental studies
NASA Technical Reports Server (NTRS)
Nicol, M. F.; Johnson, M.; Koumvakalis, A. S.
1984-01-01
Progress is reported on a project to determine the properties and boundaries of high pressure phases of the H2-He-H2O-NH3-CH4 system that are needed to constrain theoretical models of the interiors of the major planets. This project is one of the first attempts to measure phase equilibria in binary fluid-solid systems in diamond anvil cells. Vibrational spectroscopy, direct visual observations, and X-ray diffraction crystallography of materials confined in externally heated cells are the primary experimental probes. Adiabats of these materials are also measured in order to constrain models of heat flow in these bodies and to detect phase transitions by thermal anomalies. Initial efforts involve the NH3-H2O binary. This system is especially relevant to models for surface reconstruction of the icy satellites of Jupiter and Saturn. Thermal analysis experiments were completed for the P-X space, p4GPa:0 or = 0.50, near room temperature. The cryostat, sample handling equipment, and optics needed to extend the optical P-T-X work below room temperature was completed.
What spatial scales are believable for climate model projections of sea surface temperature?
NASA Astrophysics Data System (ADS)
Kwiatkowski, Lester; Halloran, Paul R.; Mumby, Peter J.; Stephenson, David B.
2014-09-01
Earth system models (ESMs) provide high resolution simulations of variables such as sea surface temperature (SST) that are often used in off-line biological impact models. Coral reef modellers have used such model outputs extensively to project both regional and global changes to coral growth and bleaching frequency. We assess model skill at capturing sub-regional climatologies and patterns of historical warming. This study uses an established wavelet-based spatial comparison technique to assess the skill of the coupled model intercomparison project phase 5 models to capture spatial SST patterns in coral regions. We show that models typically have medium to high skill at capturing climatological spatial patterns of SSTs within key coral regions, with model skill typically improving at larger spatial scales (≥4°). However models have much lower skill at modelling historical warming patters and are shown to often perform no better than chance at regional scales (e.g. Southeast Asian) and worse than chance at finer scales (<8°). Our findings suggest that output from current generation ESMs is not yet suitable for making sub-regional projections of change in coral bleaching frequency and other marine processes linked to SST warming.
The characteristics and interpretability of land surface change and implications for project design
Sohl, Terry L.; Gallant, Alisa L.; Loveland, Thomas R.
2004-01-01
The need for comprehensive, accurate information on land-cover change has never been greater. While remotely sensed imagery affords the opportunity to provide information on land-cover change over large geographic expanses at a relatively low cost, the characteristics of land-surface change bring into question the suitability of many commonly used methodologies. Algorithm-based methodologies to detect change generally cannot provide the same level of accuracy as the analyses done by human interpreters. Results from the Land Cover Trends project, a cooperative venture that includes the U.S. Geological Survey, Environmental Protection Agency, and National Aeronautics and Space Administration, have shown that land-cover conversion is a relatively rare event, occurs locally in small patches, varies geographically and temporally, and is spectrally ambiguous. Based on these characteristics of change and the type of information required, manual interpretation was selected as the primary means of detecting change in the Land Cover Trends project. Mixtures of algorithm-based detection and manual interpretation may often prove to be the most feasible and appropriate design for change-detection applications. Serious examination of the expected characteristics and measurability of change must be considered during the design and implementation phase of any change analysis project.
NASA Astrophysics Data System (ADS)
Mak, H. M.; Ng, C. O.
2010-11-01
The present work aims to study low-Reynolds-number flow through a microchannel with superhydrophobic surfaces, which contain a periodic array of parallel ribs on the upper and lower walls. Mimicking impregnation, the liquid is allowed to penetrate the grooves between the ribs which are filled with an inviscid gas. The array of ribs and grooves gives a heterogeneous wall boundary condition to the channel flow, with partial-slip boundary condition on the solid surface and no-shear boundary condition on the liquid-gas interface. Using the method of eigenfunction expansions and domain decomposition, semi-analytical models are developed for four configurations. Two of them are for longitudinal flow and the others are for transverse flow. For each flow orientation, in-phase and out-phase alignments of ribs between the upper and lower walls are analyzed. The effect of the phase alignments of ribs is appreciable when the channel height is sufficiently small. In-phase alignment gives rise to a larger effective slip length in longitudinal flow. On the contrary, out-phase alignment will yield a larger effective slip length in transverse flow. This work was supported by the Research Grants Council of the Hong Kong Special Administrative Region, China, through Project HKU 7156/09E.
Cluster observations of Shear-mode surface waves diverging from Geomagnetic Tail reconnection
NASA Astrophysics Data System (ADS)
Dai, L.; Wygant, J. R.; Dombeck, J. P.; Cattell, C. A.; Thaller, S. A.; Mouikis, C.; Balogh, A.; Reme, H.
2010-12-01
We present the first Cluster spacecraft study of the intense (δB/B~0.5, δE/VAB~0.5) equatorial plane surface waves diverging from magnetic reconnection in the geomagnetic tail at ~17 Re. Using phase lag analysis with multi-spacecraft measurements, we quantitatively determine the wavelength and phase velocity of the waves with spacecraft frame frequencies from 0.03 Hz to 1 Hz and wavelengths from much larger (4Re) than to comparable to the H+ gyroradius (~300km). The phase velocities track the strong variations in the equatorial plane projection of the reconnection outflow velocity perpendicular to the magnetic field. The propagation direction and wavelength of the observed surface waves resemble those of flapping waves of the magnetotail current sheet, suggesting a same origin shared by both of these waves. The observed waves appear ubiquitous in the outflows near magnetotail reconnection. Evidence is found that the observed waves are associated with velocity shear in reconnection outflows. Analysis shows that observed waves are associated with strong field-aligned Alfvenic Poynting flux directed away from the reconnection region toward Earth. These observations present a scenario in which the observed surface waves are driven and convected through a velocity-shear type instability by high-speed (~1000km) reconnection outflows tending to slow down due to power dissipation through Poynting flux. The mapped Poynting flux (100ergs/cm2s) and longitudinal scales (10-100 km) to 100km altitude suggest that the observed waves and their motions are an important boundary condition for night-side aurora. Figure: a) The BX-GSM in the geomagnetic tail current sheet. b) The phase difference wavelet spectrum between Bz_GSM from SC2 and SC3, used to determine the wave phase velocity, is correlated with the reconnection outflow velocity (represented by H+ VX-GSM) c) The spacecraft trajectory through magnetotail reconnection. d) The observed equatorial plane surface wave propagating outward from reconnection region.
Projecting 21st century snowpack trends in western USA mountains using variable-resolution CESM
NASA Astrophysics Data System (ADS)
Rhoades, Alan M.; Ullrich, Paul A.; Zarzycki, Colin M.
2018-01-01
Climate change will impact western USA water supplies by shifting precipitation from snow to rain and driving snowmelt earlier in the season. However, changes at the regional-to-mountain scale is still a major topic of interest. This study addresses the impacts of climate change on mountain snowpack by assessing historical and projected variable-resolution (VR) climate simulations in the community earth system model (VR-CESM) forced by prescribed sea-surface temperatures along with widely used regional downscaling techniques, the coupled model intercomparison projects phase 5 bias corrected and statistically downscaled (CMIP5-BCSD) and the North American regional climate change assessment program (NARCCAP). The multi-model RCP8.5 scenario analysis of winter season SWE for western USA mountains indicates by 2040-2065 mean SWE could decrease -19% (NARCCAP) to -38% (VR-CESM), with an ensemble median change of -27%. Contrary to CMIP5-BCSD and NARCCAP, VR-CESM highlights a more pessimistic outcome for western USA mountain snowpack in latter-parts of the 21st century. This is related to temperature changes altering the snow-albedo feedback, snowpack storage, and precipitation phase, but may indicate that VR-CESM resolves more physically consistent elevational effects lacking in statistically downscaled datasets and teleconnections that are not captured in limited area models. Overall, VR-CESM projects by 2075-2100 that average western USA mountain snowfall decreases by -30%, snow cover by -44%, SWE by -69%, and average surface temperature increase of +5.0°C. This places pressure on western USA states to preemptively invest in climate adaptation measures such as alternative water storage, water use efficiency, and reassess reservoir storage operations.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fairbank, Brian D.; Smith, Nicole
The Crump Geyser Exploration and Drilling Project – High Precision Geophysics and Detailed Structural Exploration and Slim Well Drilling ran from January 29, 2010 to September 30, 2013. During Phase 1 of the project, collection of all geophysical surveys was completed as outlined in the Statement of Project Objectives. In addition, a 5000-foot full sized exploration well was drilled by Ormat, and preexisting drilling data was discovered for multiple temperature gradient wells within the project area. Three dimensional modeling and interpretation of results from the geophysical surveys and drilling data gave confidence to move to the project into Phase 2more » drilling. Geological and geophysical survey interpretations combined with existing downhole temperature data provided an ideal target for the first slim-hole drilled as the first task in Phase 2. Slim-hole 35-34 was drilled in September 2011 and tested temperature, lithology, and permeability along the primary range-bounding fault zone near its intersection with buried northwest-trending faults that have been identified using geophysical methods. Following analysis of the results of the first slim-hole 35-34, the second slim hole was not drilled and subsequent project tasks, including flowing differential self-potential (FDSP) surveys that were designed to detail the affect of production and injection on water flow in the shallow aquifer, were not completed. NGP sold the Crump project to Ormat in August 2014, afterwards, there was insufficient time and interest from Ormat available to complete the project objectives. NGP was unable to continue managing the award for a project they did not own due to liability issues and Novation of the award was not a viable option due to federal award timelines. NGP submitted a request to mutually terminate the award on February 18, 2015. The results of all of the technical surveys and drilling are included in this report. Fault interpretations from surface geology, aeromag, seismic, and gravity data sets are in good agreement, illustrating two or more major range-bounding faults and buried northwest trending faults. The intersections of these fault systems provide the primary targets for drilling.« less
Internal Variability and Disequilibrium Confound Estimates of Climate Sensitivity from Observations
NASA Technical Reports Server (NTRS)
Marvel, Kate; Pincus, Robert; Schmidt, Gavin A.; Miller, Ron L.
2018-01-01
An emerging literature suggests that estimates of equilibrium climate sensitivity (ECS) derived from recent observations and energy balance models are biased low because models project more positive climate feedback in the far future. Here we use simulations from the Coupled Model Intercomparison Project Phase 5 (CMIP5) to show that across models, ECS inferred from the recent historical period (1979-2005) is indeed almost uniformly lower than that inferred from simulations subject to abrupt increases in CO2-radiative forcing. However, ECS inferred from simulations in which sea surface temperatures are prescribed according to observations is lower still. ECS inferred from simulations with prescribed sea surface temperatures is strongly linked to changes to tropical marine low clouds. However, feedbacks from these clouds are a weak constraint on long-term model ECS. One interpretation is that observations of recent climate changes constitute a poor direct proxy for long-term sensitivity.
Internal Variability and Disequilibrium Confound Estimates of Climate Sensitivity From Observations
NASA Astrophysics Data System (ADS)
Marvel, Kate; Pincus, Robert; Schmidt, Gavin A.; Miller, Ron L.
2018-02-01
An emerging literature suggests that estimates of equilibrium climate sensitivity (ECS) derived from recent observations and energy balance models are biased low because models project more positive climate feedback in the far future. Here we use simulations from the Coupled Model Intercomparison Project Phase 5 (CMIP5) to show that across models, ECS inferred from the recent historical period (1979-2005) is indeed almost uniformly lower than that inferred from simulations subject to abrupt increases in CO2 radiative forcing. However, ECS inferred from simulations in which sea surface temperatures are prescribed according to observations is lower still. ECS inferred from simulations with prescribed sea surface temperatures is strongly linked to changes to tropical marine low clouds. However, feedbacks from these clouds are a weak constraint on long-term model ECS. One interpretation is that observations of recent climate changes constitute a poor direct proxy for long-term sensitivity.
Drivers of Arctic Ocean warming in CMIP5 models
NASA Astrophysics Data System (ADS)
Burgard, Clara; Notz, Dirk
2017-05-01
We investigate changes in the Arctic Ocean energy budget simulated by 26 general circulation models from the Coupled Model Intercomparison Project Phase 5 framework. Our goal is to understand whether the Arctic Ocean warming between 1961 and 2099 is primarily driven by changes in the net atmospheric surface flux or by changes in the meridional oceanic heat flux. We find that the simulated Arctic Ocean warming is driven by positive anomalies in the net atmospheric surface flux in 11 models, by positive anomalies in the meridional oceanic heat flux in 11 models, and by positive anomalies in both energy fluxes in four models. The different behaviors are mainly characterized by the different changes in meridional oceanic heat flux that lead to different changes in the turbulent heat loss to the atmosphere. The multimodel ensemble mean is hence not representative of a consensus across the models in Arctic climate projections.
NASA Astrophysics Data System (ADS)
García-García, A.; Cuesta-Valero, F. J.; Beltrami, H.; Smerdon, J. E.
2017-12-01
The relationships between air and ground surface temperatures across North America are examined in the historical and future projection simulations from 32 General Circulation Models (GCMs) included in the fifth phase of the Coupled Model Intercomparison Project (CMIP5). The covariability between surface air (2 m) and ground surface temperatures (10 cm) is affected by simulated snow cover, vegetation cover and precipitation through changes in soil moisture at the surface. At high latitudes, the differences between air and ground surface temperatures, for all CMIP5 simulations, are related to the insulating effect of snow cover and soil freezing phenomena. At low latitudes, the differences between the two temperatures, for the majority of simulations, are inversely proportional to leaf area index and precipitation, likely due to induced-changes in latent and sensible heat fluxes at the ground surface. Our results show that the transport of energy across the air-ground interface differs from observations and among GCM simulations, by amounts that depend on the components of the land-surface models that they include. The large variability among GCMs and the marked dependency of the results on the choice of the land-surface model, illustrate the need for improving the representation of processes controlling the coupling of the lower atmosphere and the land surface in GCMs as a means of reducing the variability in their representation of weather and climate phenomena, with potentially important implications for positive climate feedbacks such as permafrost and soil carbon stability.
CMIP5-based global wave climate projections including the entire Arctic Ocean
NASA Astrophysics Data System (ADS)
Casas-Prat, M.; Wang, X. L.; Swart, N.
2018-03-01
This study presents simulations of the global ocean wave climate corresponding to the surface winds and sea ice concentrations as simulated by five CMIP5 (Coupled Model Intercomparison Project Phase 5) climate models for the historical (1979-2005) and RCP8.5 scenario future (2081-2100) periods. To tackle the numerical complexities associated with the inclusion of the North Pole, the WAVEWATCH III (WW3) wave model was used with a customized unstructured Spherical Multi-Cell grid of ∼100 km offshore and ∼50 km along coastlines. The climate model simulated wind and sea ice data, and the corresponding WW3 simulated wave data, were evaluated against reanalysis and hindcast data. The results show that all the five sets of wave simulations projected lower waves in the North Atlantic, corresponding to decreased surface wind speeds there in the warmer climate. The selected CMIP5 models also consistently projected an increase in the surface wind speed in the Southern Hemisphere (SH) mid-high latitudes, which translates in an increase in the WW3 simulated significant wave height (Hs) there. The higher waves are accompanied with increased peak wave period and increased wave age in the East Pacific and Indian Oceans, and a significant counterclockwise rotation in the mean wave direction in the Southern Oceans. The latter is caused by more intense waves from the SH traveling equatorward and developing into swells. Future wave climate in the Arctic Ocean in summer is projected to be predominantly of mixed sea states, with the climatological mean of September maximum Hs ranging mostly 3-4 m. The new waves approaching Arctic coasts will be less fetch-limited as ice retreats since a predominantly southwards mean wave direction is projected in the surrounding seas.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Reports. (a) States with Phase 1 projects shall submit semi-annual progress reports (original and one copy... in the next six months. (b) Phase 2. States with Phase 2 projects shall submit progress reports... Phase 2 project progress reports shall be determined by the size and complexity of the project, and...
Code of Federal Regulations, 2011 CFR
2011-07-01
... Reports. (a) States with Phase 1 projects shall submit semi-annual progress reports (original and one copy... in the next six months. (b) Phase 2. States with Phase 2 projects shall submit progress reports... Phase 2 project progress reports shall be determined by the size and complexity of the project, and...
40 CFR 35.1650-2 - Limitations on awards.
Code of Federal Regulations, 2010 CFR
2010-07-01
... which shall be completed before the project is awarded. (b) Before awarding Phase 2 projects, the Regional Administrator shall further determine that: (1) When a Phase 1 project was awarded, the final... restoration plan selected under the Phase 1 project must be implemented under a Phase 2 cooperative agreement...
MO-DE-207A-06: ECG-Gated CT Reconstruction for a C-Arm Inverse Geometry X-Ray System
DOE Office of Scientific and Technical Information (OSTI.GOV)
Slagowski, JM; Dunkerley, DAP
2016-06-15
Purpose: To obtain ECG-gated CT images from truncated projection data acquired with a C-arm based inverse geometry fluoroscopy system, for the purpose of cardiac chamber mapping in interventional procedures. Methods: Scanning-beam digital x-ray (SBDX) is an inverse geometry fluoroscopy system with a scanned multisource x-ray tube and a photon-counting detector mounted to a C-arm. In the proposed method, SBDX short-scan rotational acquisition is performed followed by inverse geometry CT (IGCT) reconstruction and segmentation of contrast-enhanced objects. The prior image constrained compressed sensing (PICCS) framework was adapted for IGCT reconstruction to mitigate artifacts arising from data truncation and angular undersampling duemore » to cardiac gating. The performance of the reconstruction algorithm was evaluated in numerical simulations of truncated and non-truncated thorax phantoms containing a dynamic ellipsoid to represent a moving cardiac chamber. The eccentricity of the ellipsoid was varied at frequencies from 1–1.5 Hz. Projection data were retrospectively sorted into 13 cardiac phases. Each phase was reconstructed using IGCT-PICCS, with a nongated gridded FBP (gFBP) prior image. Surface accuracy was determined using Dice similarity coefficient and a histogram of the point distances between the segmented surface and ground truth surface. Results: The gated IGCT-PICCS algorithm improved surface accuracy and reduced streaking and truncation artifacts when compared to nongated gFBP. For the non-truncated thorax with 1.25 Hz motion, 99% of segmented surface points were within 0.3 mm of the 15 mm diameter ground truth ellipse, versus 1.0 mm for gFBP. For the truncated thorax phantom with a 40 mm diameter ellipse, IGCT-PICCS surface accuracy measured 0.3 mm versus 7.8 mm for gFBP. Dice similarity coefficient was 0.99–1.00 (IGCT-PICCS) versus 0.63–0.75 (gFBP) for intensity-based segmentation thresholds ranging from 25–75% maximum contrast. Conclusions: The PICCS algorithm was successfully applied to reconstruct truncated IGCT projection data with angular undersampling resulting from simulated cardiac gating. Research supported by the National Heart, Lung, and Blood Institute of the NIH under award number R01HL084022. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.« less
NASA Astrophysics Data System (ADS)
Yazyev, Oleg V.; Autès, Gabriel; Isaeva, Anna; Moreschini, Luca; Johannsen, Jens C.; Pisoni, Andrea; Filatova, Taisia G.; Kuznetsov, Alexey N.; Forró, László; van den Broek, Wouter; Kim, Yeongkwan; Denlinger, Jonathan D.; Rotenberg, Eli; Bostwick, Aaron; Grioni, Marco
2015-03-01
A new strong Z2 topological insulator is theoretically predicted and experimentally confirmed in the β-phase of quasi-one-dimensional bismuth iodide Bi4I4. According to our first-principles calculations the material is characterized by Z2 invariants (1;110) making it the first representative of this topological class. Importantly, the electronic structure of β-Bi4I4 is in proximity with both the weak topological insulator phase (0;001) and the trivial phase (0;000), suggesting that a high degree of control over the topological electronic properties of this material can be achieved. Experimentally produced samples of this material appears to be practically defect-free, which results in a low concentration of intrinsic charge carriers. By using angle-resolved photoemission spectroscopy (ARPES) on the (001) surface we confirm the theoretical predictions of a highly anisotropic band structure with a small band gap hosting topological surface states centered at the M point, at the boundary of the surface Brillouin zone. We acknowledge support from Swiss NSF, ERC project ``TopoMat'', NCCR-MARVEL, DFG and US DoE. G.A., A.I., L.M. and J.C.J. contributed equally to this work.
Control of Oscillatory Thermocapillary Convection in Microgravity
NASA Technical Reports Server (NTRS)
Skarda, Ray
1998-01-01
This project focused on the generation and suppression of oscillatory thermocapillary convection in a thin liquid layer. The bulk of the research was experimental in nature, some theoretical work was also done. ne first phase of this research generated, for the first time, the hydrothermal-wave instability predicted by Smith and Davis in 1983. In addition, the behavior of the fluid layer under a number of conditions was investigated and catalogued. A transition map for the instability of buoyancy-thermocapillary convection was prepared which presented results in terms of apparatus-dependent and apparatus-independent parameters, for ease of comparison with theoretical results. The second phase of this research demonstrated the suppression of these hydrothermal waves through an active, feed-forward control strategy employing a CO2 laser to selectively heat lines of negative disturbance temperature on the free surface of the liquid layer. An initial attempt at this control was only partially successful, employing a thermocouple inserted slightly below the free surface of the liquid to generate the control scheme. Subsequent efforts, however, were completely successful in suppressing oscillations in a portion of the layer by utilizing data from an infrared image of the free surface to compute hydrothermal-wave phase speeds and, using these, to tailor the control scheme to each passing wave.
Liquid Fuels: Pyrolytic Degradation and Fire Spread Behavior as Influenced by Buoyancy
NASA Technical Reports Server (NTRS)
Ross, Howard D. (Technical Monitor); Yeboah, Yaw D.
2003-01-01
This project was conducted by the Combustion and Emission Control Lab in the Engineering Department at Clark Atlanta University under NASA Grant No. NCC3-707. The work aimed at providing data to supplement the ongoing NASA research activities on flame spread across liquid pools by providing flow visualization and velocity measurements especially in the gas phase and gas-liquid interface. During this investigation, the detailed physics of flame spread across liquid pools was revealed using particle image velocimetry (PIV), 3-dimensional Laser Doppler velocimetry (LDV) and high-speed video imaging system (HSVS). Flow fields (front and side views) of both the liquid and gas phases were visually investigated for the three subflash regimes of flame spread behavior. Some interesting findings obtained from the front and side views on flame spread across butanol pools are presented. PIV results showed the size of the transient vortex in the liquid phase near the flame front varied with the initial pool temperature. The transient vortex ahead of the flame front in the gas phase was, for the first time, clearly observed located just within 0-3 mm above the liquid surface and its size was dependent on the initial pool temperature. We calculated the flow velocity at 1 mm below the liquid surface near the flame front and inferred the generation mechanism of the vortex in the gas phase. Finally, after comparison of the flow velocity of the liquid surface and the flame spread rate, a reasonable explanation to the formation mechanism of the pulsating characteristic was proposed. This explanation is compatible with the previous numerical calculations and deductions.
Multi-Mode Cavity Accelerator Structure
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jiang, Yong; Hirshfield, Jay Leonard
2016-11-10
This project aimed to develop a prototype for a novel accelerator structure comprising coupled cavities that are tuned to support modes with harmonically-related eigenfrequencies, with the goal of reaching an acceleration gradient >200 MeV/m and a breakdown rate <10 -7/pulse/meter. Phase I involved computations, design, and preliminary engineering of a prototype multi-harmonic cavity accelerator structure; plus tests of a bimodal cavity. A computational procedure was used to design an optimized profile for a bimodal cavity with high shunt impedance and low surface fields to maximize the reduction in temperature rise ΔT. This cavity supports the TM010 mode and its 2ndmore » harmonic TM011 mode. Its fundamental frequency is at 12 GHz, to benchmark against the empirical criteria proposed within the worldwide High Gradient collaboration for X-band copper structures; namely, a surface electric field E sur max< 260 MV/m and pulsed surface heating ΔT max< 56 °K. With optimized geometry, amplitude and relative phase of the two modes, reductions are found in surface pulsed heating, modified Poynting vector, and total RF power—as compared with operation at the same acceleration gradient using only the fundamental mode.« less
A LEGO Mindstorms Brewster angle microscope
NASA Astrophysics Data System (ADS)
Fernsler, Jonathan; Nguyen, Vincent; Wallum, Alison; Benz, Nicholas; Hamlin, Matthew; Pilgram, Jessica; Vanderpoel, Hunter; Lau, Ryan
2017-09-01
A Brewster Angle Microscope (BAM) built from a LEGO Mindstorms kit, additional LEGO bricks, and several standard optics components, is described. The BAM was built as part of an undergraduate senior project and was designed, calibrated, and used to image phospholipid, cholesterol, soap, and oil films on the surface of water. A BAM uses p-polarized laser light reflected off a surface at the Brewster angle, which ideally yields zero reflectivity. When a film of different refractive index is added to the surface a small amount of light is reflected, which can be imaged in a microscope camera. Films of only one molecule (approximately 1 nm) thick, a monolayer, can be observed easily in the BAM. The BAM was used in a junior-level Physical Chemistry class to observe phase transitions of a monolayer and the collapse of a monolayer deposited on the water surface in a Langmuir trough. Using a photometric calculation, students observed a change in thickness of a monolayer during a phase transition of 7 Å, which was accurate to within 1 Å of the value determined by more advanced methods. As supplementary material, we provide a detailed manual on how to build the BAM, software to control the BAM and camera, and image processing software.
Method for 3D profilometry measurement based on contouring moire fringe
NASA Astrophysics Data System (ADS)
Shi, Zhiwei; Lin, Juhua
2007-12-01
3D shape measurement is one of the most active branches of optical research recently. A method of 3D profilometry measurement by the combination of Moire projection method and phase-shifting technology based on SCM (Single Chip Microcomputer) control is presented in the paper. Automatic measurement of 3D surface profiles can be carried out by applying this method with high speed and high precision.
Cryogenic Selective Surfaces: A Phase 2 NIAC Project: Mid-Term Continuation Review
NASA Technical Reports Server (NTRS)
Youngquist, Robert; Nurge, Mark; Gibson, Tracy; Johnson, Wesley
2017-01-01
The NASA Innovative Advanced Concepts (NIAC) program has been funding work at KSC (Kennedy Space Center) on a new coating that should allow cryogenic commodities to be stored in deep space. Recently a mid-term review of this work was given. I am requesting that this presentation be cleared for release so that the material can be presented publicly at an upcoming FISO (Future in Space) telecom.
Advanced underground Vehicle Power and Control: The locomotive Research Platform
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vehicle Projects LLC
2003-01-28
Develop a fuelcell mine locomotive with metal-hydride hydrogen storage. Test the locomotive for fundamental limitations preventing successful commercialization of hydride fuelcells in underground mining. During Phase 1 of the DOE-EERE sponsored project, FPI and its partner SNL, completed work on the development of a 14.4 kW fuelcell power plant and metal-hydride energy storage. An existing battery-electric locomotive with similar power requirements, minus the battery module, was used as the base vehicle. In March 2001, Atlas Copco Wagner of Portland, OR, installed the fuelcell power plant into the base vehicle and initiated integration of the system into the vehicle. The entiremore » vehicle returned to Sandia in May 2001 for further development and integration. Initial system power-up took place in December 2001. A revision to the original contract, Phase 2, at the request of DOE Golden Field Office, established Vehicle Projects LLC as the new prime contractor,. Phase 2 allowed industry partners to conduct surface tests, incorporate enhancements to the original design by SNL, perform an extensive risk and safety analysis, and test the fuelcell locomotive underground under representative production mine conditions. During the surface tests one of the fuelcell stacks exhibited reduced power output resulting in having to replace both fuelcell stacks. The new stacks were manufactured with new and improved technology resulting in an increase of the gross power output from 14.4 kW to 17 kW. Further work by CANMET and Hatch Associates, an engineering consulting firm specializing in safety analysis for the mining industry, both under subcontract to Vehicle Projects LLC, established minimum requirements for underground testing. CANMET upgraded the Programmable Logic Control (PLC) software used to monitor and control the fuelcell power plant, taking into account locomotive operator's needs. Battery Electric, a South Africa manufacturer, designed and manufactured (at no cost to the project) a new motor controller capable of operating the higher rpm motor and different power characteristics of the fuelcells. In early August 2002, CANMET, with the technical assistance of Nuvera Fuel Cells and Battery Electric, installed the new PLC software, installed the new motor controller, and installed the new fuelcell stacks. After minor adjustments, the fuelcell locomotive pulled its first fully loaded ore cars on a surface track. The fuelcell-powered locomotive easily matched the battery powered equivalent in its ability to pull tonnage and equaled the battery-powered locomotive in acceleration. The final task of Phase 2, testing the locomotive underground in a production environment, occurred in early October 2002 in a gold mine. All regulatory requirements to allow the locomotive underground were completed and signed off by Hatch Associates prior to going underground. During the production tests, the locomotive performed flawlessly with no failures or downtime. The actual tests occurred during a 2-week period and involved moving both gold ore and waste rock over a 1,000 meter track. Refueling, or recharging, of the metal-hydride storage took place on the surface. After each shift, the metal-hydride storage module was removed from the locomotive, transported to surface, and filled with hydrogen from high-pressure tanks. The beginning of each shift started with taking the fully recharged metal-hydride storage module down into the mine and re-installing it onto the locomotive. Each 8 hour shift consumed approximately one half to two thirds of the onboard hydrogen. This indicates that the fuelcell-powered locomotive can work longer than a similar battery-powered locomotive, which operates about 6 hours, before needing a recharge.« less
Mission Applications Support at NASA: The Proposal Surface Water and Ocean Topography Mission
NASA Astrophysics Data System (ADS)
Srinivasan, Margaret; Peterson, Craig; Callahan, Phil
2013-09-01
The NASA Applied Sciences Program is actively supporting an agency-wide effort to formalize a mission-level data applications approach. The program goal is to engage early-phase NASA Earth satellite mission project teams with applied science representation in the flight mission planning process. The end objective is to "to engage applications-oriented users and organizations early in the satellite mission lifecycle to enable them to envision possible applications and integrate end-user needs into satellite mission planning as a way to increase the benefits to the nation."Two mission applications representatives have been selected for each early phase Tier 2 mission, including the Surface Water and Ocean Topography (SWOT) mission concept. These representatives are tasked with identifying and organizing the applications communities and developing and promoting a process for the mission to optimize the reach of existing applications efforts in order to enhance the applications value of the missions. An early project-level awareness of mission planning decisions that may increase or decrease the utility of data products to diverse user and potential user communities (communities of practice and communities of potential, respectively) has high value and potential return to the mission and to the users.Successful strategies to enhance science and practical applications of projected SWOT data streams will require engaging with and facilitating between representatives in the science, societal applications, and mission planning communities.Some of the elements of this program include:• Identify early adopters of data products• Coordinate applications team, including;Project Scientist, Payload Scientist, ProjectManager, data processing lead• Describe mission and products sufficiently inearly stage of development to effectively incorporate all potential usersProducts and activities resulting from this effort will include (but are not limited to); workshops, workshop summaries, web pages, email lists of interested users/scientists, an Applications Plan, printed materials (posters, brochures) and participation in key meetings.
Colloidal Particles at Fluid Interfaces and the Interface of Colloidal Fluids
NASA Astrophysics Data System (ADS)
McGorty, Ryan
Holographic microscopy is a unifying theme in the different projects discussed in this thesis. The technique allows one to observe microscopic objects, like colloids and droplets, in a three-dimensional (3D) volume. Unlike scanning 3D optical techniques, holography captures a sample's 3D information in a single image: the hologram. Therefore, one can capture 3D information at video frame rates. The price for such speed is paid in computation time. The 3D information must be extracted from the image by methods such as reconstruction or fitting the hologram to scattering calculations. Using holography, we observe a single colloidal particle approach, penetrate and then slowly equilibrate at an oil--water interface. Because the particle moves along the optical axis (z-axis) and perpendicular to the interface holography is used to determine its position. We are able to locate the particle's z-position to within a few nanometers with a time resolution below a millisecond. We find that the capillary force pulling the particle into the interface is not balanced by a hydrodynamic force. Rather, a larger-than-viscous dissipation associated with the three-phase contact-line slipping over the particle's surface results in equilibration on time scales orders of magnitude longer than the minute time scales over which our setup allows us to examine. A separate project discussed here also examines colloidal particles and fluid-fluid interfaces. But the fluids involved are composed of colloids. With a colloid and polymer water-based mixture we study the phase separation of the colloid-rich (or liquid) and colloid-poor (or gas) region. In comparison to the oil--water interface in the previously mentioned project, the interface between the colloidal liquid and gas phases has a surface tension nearly six orders of magnitude smaller. So interfacial fluctuations are observable under microscopy. We also use holographic microscopy to study this system but not to track particles with great time and spatial resolution. Rather, holography allows us to observe nucleation of the liquid phase occurring throughout our sample volume.
State and county delivered bridge replacement project analysis : phase I and phase II.
DOT National Transportation Integrated Search
2010-02-01
The purpose of the study was to compare the cost of state delivered bridge projects and county delivered bridge projects. A total of 190 different bridge replacement projects were analyzed. The first phase of the project focused on whether or not the...
NASA Technical Reports Server (NTRS)
Florance, Jennifer P.; Burner, Alpheus W.; Fleming, Gary A.; Martin, Christopher A.
2003-01-01
An overview of the contributions of the NASA Langley Research Center (LaRC) to the DARPA/AFRL/NASA/ Northrop Grumman Corporation (NGC) Smart Wing program is presented. The overall objective of the Smart Wing program was to develop smart** technologies and demonstrate near-flight-scale actuation systems to improve the aerodynamic performance of military aircraft. NASA LaRC s roles were to provide technical guidance, wind-tunnel testing time and support, and Computational Fluid Dynamics (CFD) analyses. The program was divided into two phases, with each phase having two wind-tunnel entries in the Langley Transonic Dynamics Tunnel (TDT). This paper focuses on the fourth and final wind-tunnel test: Phase 2, Test 2. During this test, a model based on the NGC Unmanned Combat Air Vehicle (UCAV) concept was tested at Mach numbers up to 0.8 and dynamic pressures up to 150 psf to determine the aerodynamic performance benefits that could be achieved using hingeless, smoothly-contoured control surfaces actuated with smart materials technologies. The UCAV-based model was a 30% geometric scale, full-span, sting-mounted model with the smart control surfaces on the starboard wing and conventional, hinged control surfaces on the port wing. Two LaRC-developed instrumentation systems were used during the test to externally measure the shapes of the smart control surface and quantify the effects of aerodynamic loading on the deflections: Videogrammetric Model Deformation (VMD) and Projection Moire Interferometry (PMI). VMD is an optical technique that uses single-camera photogrammetric tracking of discrete targets to determine deflections at specific points. PMI provides spatially continuous measurements of model deformation by computationally analyzing images of a grid projected onto the model surface. Both the VMD and PMI measurements served well to validate the use of on-board (internal) rotary potentiometers to measure the smart control surface deflection angles. Prior to the final entry, NASA LaRC also performed three-dimensional unstructured Navier Stokes CFD analyses in an attempt to predict the potential aerodynamic impact of the smart control surface on overall model forces and moments. Eight different control surface shapes were selected for study at Mach = 0.6, Reynolds number = 3.25 x 10(exp 6), and + 2 deg., 3 deg., 8 deg., and 10 deg.model angles-of-attack. For the baseline, undeflected control surface geometry, the CFD predictions and wind-tunnel results matched well. The agreement was not as good for the more complex aero-loaded control surface shapes, though, because of the inability to accurately predict those shapes. Despite these results, the NASA CFD study served as an important step in studying advanced control effectors.
Application of MIMO Techniques in sky-surface wave hybrid networking sea-state radar system
NASA Astrophysics Data System (ADS)
Zhang, L.; Wu, X.; Yue, X.; Liu, J.; Li, C.
2016-12-01
The sky-surface wave hybrid networking sea-state radar system contains of the sky wave transmission stations at different sites and several surface wave radar stations. The subject comes from the national 863 High-tech Project of China. The hybrid sky-surface wave system and the HF surface wave system work simultaneously and the HF surface wave radar (HFSWR) can work in multi-static and surface-wave networking mode. Compared with the single mode radar system, this system has advantages of better detection performance at the far ranges in ocean dynamics parameters inversion. We have applied multiple-input multiple-output(MIMO) techniques in this sea-state radar system. Based on the multiple channel and non-causal transmit beam-forming techniques, the MIMO radar architecture can reduce the size of the receiving antennas and simplify antenna installation. Besides, by efficiently utilizing the system's available degrees of freedom, it can provide a feasible approach for mitigating multipath effect and Doppler-spread clutter in Over-the-horizon Radar. In this radar, slow-time phase-coded MIMO method is used. The transmitting waveforms are phase-coded in slow-time so as to be orthogonal after Doppler processing at the receiver. So the MIMO method can be easily implemented without the need to modify the receiver hardware. After the radar system design, the MIMO experiments of this system have been completed by Wuhan University during 2015 and 2016. The experiment used Wuhan multi-channel ionospheric sounding system(WMISS) as sky-wave transmitting source and three dual-frequency HFSWR developed by the Oceanography Laboratory of Wuhan University. The transmitter system located at Chongyang with five element linear equi-spaced antenna array and Wuhan with one log-periodic antenna. The RF signals are generated by synchronized, but independent digital waveform generators - providing complete flexibility in element phase and amplitude control, and waveform type and parameters. The field experimental results show the presented method is effective. The echoes are obvious and distinguishable both in co-located MIMO mode and widely distributed MIMO mode. Key words: sky-surface wave hybrid networking; sea-state radar; MIMO; phase-coded
Surface Accuracy and Pointing Error Prediction of a 32 m Diameter Class Radio Astronomy Telescope
NASA Astrophysics Data System (ADS)
Azankpo, Severin
2017-03-01
The African Very-long-baseline interferometry Network (AVN) is a joint project between South Africa and eight partner African countries aimed at establishing a VLBI (Very-Long-Baseline Interferometry) capable network of radio telescopes across the African continent. An existing structure that is earmarked for this project, is a 32 m diameter antenna located in Ghana that has become obsolete due to advances in telecommunication. The first phase of the conversion of this Ghana antenna into a radio astronomy telescope is to upgrade the antenna to observe at 5 GHz to 6.7 GHz frequency and then later to 18 GHz within a required performing tolerance. The surface and pointing accuracies for a radio telescope are much more stringent than that of a telecommunication antenna. The mechanical pointing accuracy of such telescopes is influenced by factors such as mechanical alignment, structural deformation, and servo drive train errors. The current research investigates the numerical simulation of the surface and pointing accuracies of the Ghana 32 m diameter radio astronomy telescope due to its structural deformation mainly influenced by gravity, wind and thermal loads.
Status of the Large Underground Xenon (LUX) Detector
NASA Astrophysics Data System (ADS)
Larsen, Nicole
2012-03-01
The LUX (Large Underground Xenon) experiment is a 350-kg xenon-based direct dark matter detection experiment consisting of a two-phase (liquid/gas) xenon time projection chamber with a 100-kg fiducial mass. This technology has many advantages, including scalability, self-shielding, the absence of any long-lived isotopes, high gamma ray stopping power, and the ability to precisely measure the charge-to-light ratio of interactions within the detector, which provides an accurate method for discriminating between electron recoils (gamma rays, beta decays) and nuclear recoils (neutrons, WIMPS) within the detector. LUX's projected sensitivity for 300 days of acquisition is a cross-section of 7 x10-46 cm^2 for a WIMP mass of 100 GeV, representing an increase of nearly an order of magnitude over previous WIMP cross-section limits. From November 2011 through February 2012, LUX was deployed in a surface laboratory at the Homestake Mine in South Dakota for its second surface run. This talk will provide an overview of the LUX design and a report on the status of the experiment after the surface run and before underground deployment.
Xiang, Baoqiang; Zhao, Ming; Held, Isaac M.; ...
2017-02-13
The severity of the double Intertropical Convergence Zone (DI) problem in climate models can be measured by a tropical precipitation asymmetry index (PAI), indicating whether tropical precipitation favors the Northern Hemisphere or the Southern Hemisphere. Examination of 19 Coupled Model Intercomparison Project phase 5 models reveals that the PAI is tightly linked to the tropical sea surface temperature (SST) bias. As one of the factors determining the SST bias, the asymmetry of tropical net surface heat flux in Atmospheric Model Intercomparison Project (AMIP) simulations is identified as a skillful predictor of the PAI change from an AMIP to a coupledmore » simulation, with an intermodel correlation of 0.90. Using tropical top-of-atmosphere (TOA) fluxes, the correlations are lower but still strong. However, the extratropical asymmetries of surface and TOA fluxes in AMIP simulations cannot serve as useful predictors of the PAI change. Furthermore, this study suggests that the largest source of the DI bias is from the tropics and from atmospheric models.« less
Challenge to image the stagnant slab beneath the Philippine Sea by seafloor electromagnetic survey
NASA Astrophysics Data System (ADS)
Utada, H.; Baba, K.; Goto, T.; Kasaya, T.; Ichikita, T.; Tada, N.; Shimizu, H.; Koyama, T.; Uyeshima, M.
2007-12-01
We have run a seafloor electromagnetic survey project in the Philippine Sea in order to image the deep mantle slab stagnating in the transition zone and surrounding mantle in three dimensions. Seafloor observations at every 500 km or so is necessary to resolve the geometry of the slab because existing data sets are based on the observations by land geomagnetic stations and submarine cables, which are distributed coarsely and unevenly. Although it is difficult to establish a bunch of nearly permanent observation stations at seafloor, iterative maneuver observations using ocean bottom electromagnetometers (OBEMs) can acquire the data required to probe down to the mantle transition zone. The project iterates one-year-long deployment three times. Earthquake Research Institute, University of Tokyo and Institute for Research on Earth Evolution (IFREE), Japan Agency for Marine-Earth Science and Technology (JAMSTEC) have resourced the project with the OBEMs. In the first phase, we deployed 11 OBEMs in October, 2005 and recovered all of them successfully in November, 2006. R/V Kairei of JAMSTEC was utilized for both cruises. In the second cruise, we deployed another 12 OBEMs and started the second phase. The recovery of the OBEMs and the third initiation will be done in November, 2007. The quality of the first phase data is quite good except for the electric field at one site. The MT responses are estimated at 10 sites in the period range of from about 300 to 60,000 seconds. The geomagnetic transfer functions are also estimated at all the 11 sites in the range of about 300 to 1,000,000 seconds. The responses at the period longer than 100,000 seconds are somewhat inaccurate and the improvement is expected by further data collection in the second and third phases. These responses will be analyzed together with the responses which were obtained by past experiments in the Philippine Sea. The features of the responses may be classified by basins composing the Philippine Sea plate. Some of these features are explained by land-ocean distribution and seafloor topography. Three-dimensional forward modelling study is now on going to examine effects of the surface heterogeneities and some simple patterns of sub-surface heterogeneities. These results and preliminary report on the second phase will be presented in the meeting.
Pareto-Optimal Estimates of California Precipitation Change
NASA Astrophysics Data System (ADS)
Langenbrunner, Baird; Neelin, J. David
2017-12-01
In seeking constraints on global climate model projections under global warming, one commonly finds that different subsets of models perform well under different objective functions, and these trade-offs are difficult to weigh. Here a multiobjective approach is applied to a large set of subensembles generated from the Climate Model Intercomparison Project phase 5 ensemble. We use observations and reanalyses to constrain tropical Pacific sea surface temperatures, upper level zonal winds in the midlatitude Pacific, and California precipitation. An evolutionary algorithm identifies the set of Pareto-optimal subensembles across these three measures, and these subensembles are used to constrain end-of-century California wet season precipitation change. This methodology narrows the range of projections throughout California, increasing confidence in estimates of positive mean precipitation change. Finally, we show how this technique complements and generalizes emergent constraint approaches for restricting uncertainty in end-of-century projections within multimodel ensembles using multiple criteria for observational constraints.
NASA Astrophysics Data System (ADS)
Whitehurst, A.; Murphy, K. J.
2017-12-01
The objectives of the NASA Citizen Science for Earth Systems Program (CSESP) include both the evaluation of using citizen science data in NASA Earth science related research and engaging the public in Earth systems science. Announced in 2016, 16 projects were funded for a one year prototype phase, with the possibility of renewal for 3 years pending a competitive evaluation. The current projects fall into the categories of atmospheric composition (5), biodiversity and conservation (5), and surface hydrology/water and energy cycle (6). Out of the 16, 8 of the projects include the development and/or implementation of low cost sensors to facilitate data collection. This presentation provides an overview of the NASA CSESP program to both highlight the diversity of innovative projects being funded and to share information with future program applicants.
Productivity improvement in engineering at Rocketdyne
NASA Technical Reports Server (NTRS)
Nordlund, R. M.; Vogt, S. T.; Woo, A. K.
1985-01-01
The Rocketdyne Division of Rockwell International has embarked on a productivity improvement program in engineering. This effort included participation in the White Collar Productivity Improvement (WCPI) project sponsored by the American Productivity Center. A number of things have been learned through this project. It seems that any productivity improvement project should be employee driven. The Rocketdyne project was essentially started as a result of a grassroots effort to remove some particular hindrances, and employee enthusiasm was a prime factor in the continuing progress of the effort. A significant result was that awareness of problems at all levels increased. Many issues surfaced in the diagnostic phase, and were then noted and discussed. This process added legitimacy to issues that had previously been merely unspoken concerns. The initial feelings of many members of the pilot group was that significant changes would occur relatively quickly. It is now recognized that this will have to be an ongoing, long-term effort.
DOT National Transportation Integrated Search
2010-02-01
The purpose of the study was to compare the cost of state delivered bridge projects and county delivered bridge projects. A total of 190 different bridge replacement projects were analyzed. The first phase of the project focused on whether or not the...
Towards a better control of optics cleanliness
NASA Astrophysics Data System (ADS)
Berlioz, P.
2017-11-01
The contamination of optics can considerably degrade the transmission and scattering of spacecraft optics. To prevent efficiently optics from contamination involves introducing since design phase requirements on materials and protections (covers…). Then, integration and test phase demands to implement heavy and stringent means (clean room, specific garment, covers…) and a permanent monitoring by fine contamination measurement of instrument environment and surfaces. Contamination budgets are drawn the project along, first prediction budgets based on analysis and potentially modeling, during design phase, then actual budgets based on contamination measurement during integration and test phase. Finally, the risk still exists to have to clean optics because of hazardous contamination, furthermore to dismount them. The cleanliness engineering set at ASTRIUM Toulouse is presented here, including the contamination monitoring via witness samples measured by IR spectrometry and via counters. ASTRIUM is presently focusing attention on no contact cleaning like the promising UV-ozone process.
NASA Astrophysics Data System (ADS)
Inanç, Arda; Kösoğlu, Gülşen; Yüksel, Heba; Naci Inci, Mehmet
2018-06-01
A new fibre optic Lloyd's mirror method is developed for extracting 3-D height distribution of various objects at the micron scale with a resolution of 4 μm. The fibre optic assembly is elegantly integrated to an optical microscope and a CCD camera. It is demonstrated that the proposed technique is quite suitable and practical to produce an interference pattern with an adjustable frequency. By increasing the distance between the fibre and the mirror with a micrometre stage in the Lloyd's mirror assembly, the separation between the two bright fringes is lowered down to the micron scale without using any additional elements as part of the optical projection unit. A fibre optic cable, whose polymer jacket is partially stripped, and a microfluidic channel are used as test objects to extract their surface topographies. Point by point sensitivity of the method is found to be around 8 μm, changing a couple of microns depending on the fringe frequency and the measured height. A straightforward calibration procedure for the phase to height conversion is also introduced by making use of the vertical moving stage of the optical microscope. The phase analysis of the acquired image is carried out by One Dimensional Continuous Wavelet Transform for which the chosen wavelet is the Morlet wavelet and the carrier removal of the projected fringe patterns is achieved by reference subtraction. Furthermore, flexible multi-frequency property of the proposed method allows measuring discontinuous heights where there are phase ambiguities like 2π by lowering the fringe frequency and eliminating the phase ambiguity.
NASA Astrophysics Data System (ADS)
Leng, Guoyong; Huang, Maoyi; Voisin, Nathalie; Zhang, Xuesong; Asrar, Ghassem R.; Leung, L. Ruby
2016-11-01
Despite the importance of surface water to people and ecosystems, few studies have explored detectable changes in surface water supply in a changing climate, given its large natural variability. Here we analyze runoff projections from the Variable Infiltration Capacity hydrological model driven by 97 downscaled and bias-corrected Coupled Model Intercomparison Project Phase 5 climate projections over the conterminous United States (CONUS). Our results show that more than 40% of the CONUS land area will experience significant changes in the probability distribution functions (i.e. PDFs) of summer and winter runoff by the end of the 21st century, which may pose great challenges to future surface water supply. Sub-basin mean runoff PDFs are projected to change significantly after 2040s depending on the emission scenarios, with earliest occurrence in the Pacific Northwest and northern California regions. When examining the response as a function of changes in the global mean temperature (ΔGMT), a linear relationship is revealed at the 95% confidence level. Generally, 1 °C increase of GMT leads to 11% and 17% more lands experiencing changes in summer and winter runoff PDFs, respectively. Such changes in land fraction scale with ΔGMT at the country scale independent of emission scenarios, but the same relationship does not necessarily hold at sub-basin scales, due to the larger role of atmospheric circulation changes and their uncertainties on regional precipitation. Further analyses show that the emergence of significant changes in sub-basin runoff PDFs is indicative of the emergence of new hydrology regimes and it is dominated by the changes in variability rather than shift in the mean, regardless of the emission scenarios.
POWER AND INFLUENCE CHARTING: THE GOOGLE WAY
DOE Office of Scientific and Technical Information (OSTI.GOV)
Troy Hiltbrand; Sharon Berrett
2011-07-01
The success or failure of a project may be charted in the initiation phase. Therefore, initiation is arguably the most important phase of any project. During the initiation phase, the foundation for the project is established, including the selection of project sponsors and champions and getting their buy-in, which sets the project up for success.
NASA Technical Reports Server (NTRS)
Ingersoll, A. P.; Miller, R. L.
1986-01-01
A rotating and adiabatic inviscid fluid planet possesses low frequency motions that are barotropic, quasi-geostrophic and quasi-columnar. The limiting curvature at which flow becomes unstable upon projection onto the planetary surface is negative, with an amplitude that is 3-4 times that for thin atmospheres, in planets in which density linearly decreases to zero at the surface. This result is shown to hold for all quasi-columnar perturbations. Both the phase speed of the normal mode oscillations and the barotropic stability criterion have features in common with Saturn and Jupiter oscillations.
Remote sensing of Earth terrain
NASA Technical Reports Server (NTRS)
Kong, J. A.
1992-01-01
Research findings are summarized for projects dealing with the following: application of theoretical models to active and passive remote sensing of saline ice; radiative transfer theory for polarimetric remote sensing of pine forest; scattering of electromagnetic waves from a dense medium consisting of correlated Mie scatterers with size distribution and applications to dry snow; variance of phase fluctuations of waves propagating through a random medium; theoretical modeling for passive microwave remote sensing of earth terrain; polarimetric signatures of a canopy of dielectric cylinders based on first and second order vector radiative transfer theory; branching model for vegetation; polarimetric passive remote sensing of periodic surfaces; composite volume and surface scattering model; and radar image classification.
Control characteristics for wrap-around fins on cruise missiles configurations
NASA Technical Reports Server (NTRS)
Sawyer, W. C.; Monta, W. J.; Carter, W. V.; Alexander, W. K.
1981-01-01
This paper presents selected results of a panel loads study conducted as part of the final phase of an extensive investigation of an air-breathing missile concept employing wrap-around aerodynamic surfaces. Typical results for M = 2.36 are presented for the fin load results, plus a brief review of basic results of the previously reported tests. Vapor screen results are also discussed. The present results indicate that the fin load characteristics are nearly identical for planar and curved fins having the same projected planform and would permit the use of planar-surface predictions for supersonic speeds in the preliminary design stages of missiles employing wrap-around curved fins.
The Mars Exploration Rovers Entry Descent and Landing and the Use of Aerodynamic Decelerators
NASA Technical Reports Server (NTRS)
Steltzner, Adam; Desai, Prasun; Lee, Wayne; Bruno, Robin
2003-01-01
The Mars Exploration Rovers (MER) project, the next United States mission to the surface of Mars, uses aerodynamic decelerators in during its entry, descent and landing (EDL) phase. These two identical missions (MER-A and MER-B), which deliver NASA s largest mobile science suite to date to the surface of Mars, employ hypersonic entry with an ablative energy dissipating aeroshell, a supersonic/subsonic disk-gap-band parachute and an airbag landing system within EDL. This paper gives an overview of the MER EDL system and speaks to some of the challenges faced by the various aerodynamic decelerators.
ENHANCED PRACTICAL PHOTOSYNTHETIC CO2 MITIGATION
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dr. Gregory Kremer; Dr. David J. Bayless; Dr. Morgan Vis
2001-10-15
This report documents significant achievements in the Enhanced Practical Photosynthetic CO{sub 2} Mitigation project during the period from 10/03/2000 through 10/02/2001. Most of the achievements are milestones in our efforts to complete the tasks and subtasks that constitute the project objectives. This is the fourth quarterly report for this project, so it also serves as a year-1 project review. We have made significant progress on our Phase I objectives, and our current efforts are focused on fulfilling these research objectives ''on time'' relative to the project timeline. Overall, we believe that we are on schedule to complete Phase I activitiesmore » by 10/2002, which is the milestone date from the original project timeline. Our results to date concerning the individual factors which have the most significant effect on CO{sub 2} uptake are inconclusive, but we have gathered useful information about the effects of lighting, temperature and CO{sub 2} concentration on one particular organism (Nostoc) and significant progress has been made in identifying other organisms that are more suitable for use in the bioreactor due to their better tolerance for the high temperatures likely to be encountered in the flue gas stream. Our current tests are focused on one such thermophilic organism (Cyanidium), and an enlarged bioreactor system (CRF-2) has been prepared for testing this organism. Tests on the enhanced mass transfer CO{sub 2} absorption technique are underway and useful information is currently being collected concerning pressure drop. The solar collectors for the deep-penetration hybrid solar lighting system have been designed and a single solar collector tracking unit is being prepared for installation in the pilot scale bioreactor system currently under construction. Much progress has been made in designing the fiber optic light delivery system, but final selection of the ''optimum'' delivery system design depends on many factors, most significantly the configuration and orientation of the growth surfaces in the bioreactor. For the growth surface subsystem we have identified advantages and disadvantages for several candidate growth surface materials, we have built and tested various ''screen'' systems and fluid delivery systems, and we continue to test compatibility of the candidate materials with the organisms and with the moisture delivery and harvesting system designs. These tests will be ongoing until an ''optimum'' combination of growth surface material/organism type/harvesting system is identified. For the harvesting system, a nozzle-based water jet system has been shown to be effective, but it has disadvantages for the overall system design in terms of space utilization. A streamlined and integrated screen wetting/harvesting system design is currently under development and will be the focus of harvesting system tests in the foreseeable future. This report addresses each of the key project tasks as defined in the statement of work, giving both a summary of key accomplishments over the past year and a plan for future work.« less
Full-Scale Spacecraft Simulator Design for a 2D Zero Gravity Small Body Surface Sampling Validation
NASA Astrophysics Data System (ADS)
Mongelli, Marco
NASA is developing several Touch-And-Go (TAG) classes of missions. These types of missions like the OSIRIS-REx asteroid sample return [1] or a comet sample return mission (CSSR)[2], consist usually in three phases: propulsive approach to the target, sampling and propulsion to move the spacecraft away from the target. The development of TAG mission, from concept to realization, is usually divided in two phases: Phase I discusses the major trades that could affect the mission architecture; Phase II focuses in detail on the design. This project of a spacecraft emulator fits into phase II and specifically on the way the spacecraft could react in absence of gravity while the Sample Acquisition System (SAS) is collecting the sample. A full-scale spacecraft on a 2D zero-friction environment has been designed. Also a propulsion system has been implemented to re-create the full dynamics of a spacecraft in space.
NASA Astrophysics Data System (ADS)
Kay, Jennifer E.; Bourdages, Line; Miller, Nathaniel B.; Morrison, Ariel; Yettella, Vineel; Chepfer, Helene; Eaton, Brian
2016-04-01
Spaceborne lidar observations from the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite are used to evaluate cloud amount and cloud phase in the Community Atmosphere Model version 5 (CAM5), the atmospheric component of a widely used state-of-the-art global coupled climate model (Community Earth System Model). By embedding a lidar simulator within CAM5, the idiosyncrasies of spaceborne lidar cloud detection and phase assignment are replicated. As a result, this study makes scale-aware and definition-aware comparisons between model-simulated and observed cloud amount and cloud phase. In the global mean, CAM5 has insufficient liquid cloud and excessive ice cloud when compared to CALIPSO observations. Over the ice-covered Arctic Ocean, CAM5 has insufficient liquid cloud in all seasons. Having important implications for projections of future sea level rise, a liquid cloud deficit contributes to a cold bias of 2-3°C for summer daily maximum near-surface air temperatures at Summit, Greenland. Over the midlatitude storm tracks, CAM5 has excessive ice cloud and insufficient liquid cloud. Storm track cloud phase biases in CAM5 maximize over the Southern Ocean, which also has larger-than-observed seasonal variations in cloud phase. Physical parameter modifications reduce the Southern Ocean cloud phase and shortwave radiation biases in CAM5 and illustrate the power of the CALIPSO observations as an observational constraint. The results also highlight the importance of using a regime-based, as opposed to a geographic-based, model evaluation approach. More generally, the results demonstrate the importance and value of simulator-enabled comparisons of cloud phase in models used for future climate projection.
Mars Pathfinder mission operations concepts
NASA Technical Reports Server (NTRS)
Sturms, Francis M., Jr.; Dias, William C.; Nakata, Albert Y.; Tai, Wallace S.
1994-01-01
The Mars Pathfinder Project plans a December 1996 launch of a single spacecraft. After jettisoning a cruise stage, an entry body containing a lander and microrover will directly enter the Mars atmosphere and parachute to a hard landing near the sub-solar latitude of 15 degrees North in July 1997. Primary surface operations last for 30 days. Cost estimates for Pathfinder ground systems development and operations are not only lower in absolute dollars, but also are a lower percentage of total project costs than in past planetary missions. Operations teams will be smaller and fewer than typical flight projects. Operations scenarios have been developed early in the project and are being used to guide operations implementation and flight system design. Recovery of key engineering data from entry, descent, and landing is a top mission priority. These data will be recorded for playback after landing. Real-time tracking of a modified carrier signal through this phase can provide important insight into the spacecraft performance during entry, descent, and landing in the event recorded data is never recovered. Surface scenarios are dominated by microrover activity and lander imaging during 7 hours of the Mars day from 0700 to 1400 local solar time. Efficient uplink and downlink processes have been designed to command the lander and microrover each Mars day.
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
In the Bear Creek Valley Watershed Remedial Investigation, the Boneyard/Burnyard was identified as the source of the largest releases of uranium into groundwater and surface water in Bear Creek Valley. The proposed action for remediation of this site is selective excavation and removal of source material and capping of the remainder of the site. The schedule for this action has been accelerated so that this is the first remedial action planned to be implemented in the Bear Creek Valley Record of Decision. Additional data needs to support design of the remedial action were identified at a data quality objectives meetingmore » held for this project. Sampling at the Boneyard/Burnyard will be conducted through the use of a phased approach. Initial or primary samples will be used to make in-the-field decisions about where to locate follow-up or secondary samples. On the basis of the results of surface water, soil, and groundwater analysis, up to six test pits will be dug. The test pits will be used to provide detailed descriptions of source materials and bulk samples. This document sets forth the requirements and procedures to protect the personnel involved in this project. This document also contains the health and safety plan, quality assurance project plan, waste management plan, data management plan, implementation plan, and best management practices plan for this project as appendices.« less
NASA Technical Reports Server (NTRS)
Kuhl, Christopher A.
2008-01-01
The Aerial Regional-scale Environmental Survey (ARES) is a Mars exploration mission concept designed to send an airplane to fly through the lower atmosphere of Mars, with the goal of taking scientific measurements of the atmosphere, surface, and subsurface phenomenon. ARES was first proposed to the Mars Scout program in December 2002 for a 2007 launch opportunity and was selected to proceed with a Phase A study, step-2 proposal which was submitted in May 2003. ARES was not selected for the Scout mission, but efforts continued on risk reduction of the atmospheric flight system in preparation for the next Mars Scout opportunity in 2006. The ARES concept was again proposed in July 2006 to the Mars Scout program but was not selected to proceed into Phase A. This document describes the Planetary Protection strategy that was developed in ARES Pre Phase-A activities to help identify, early in the design process, certain hardware, assemblies, and/or subsystems that will require unique design considerations based on constraints imposed by Planetary Protection requirements. Had ARES been selected as an exploration project, information in this document would make up the ARES Project Planetary Protection Plan.
NASA Astrophysics Data System (ADS)
Yang Kam Wing, G.; Sushama, L.; Diro, G. T.
2016-12-01
This study investigates the intraannual variability of soil moisture-temperature coupling over North America. To this effect, coupled and uncoupled simulations are performed with the fifth-generation Canadian Regional Climate Model (CRCM5), driven by ERA-Interim. In coupled simulations, land and atmosphere interact freely; in uncoupled simulations, the interannual variability of soil moisture is suppressed by prescribing climatological values for soil liquid and frozen water contents. The study also explores projected changes to coupling by comparing coupled and uncoupled CRCM5 simulations for current (1981-2010) and future (2071-2100) periods, driven by the Canadian Earth System Model. Coupling differs for the northern and southern parts of North America. Over the southern half, it is persistent throughout the year while for the northern half, strongly coupled regions generally follow the freezing line during the cold months. Detailed analysis of the southern Canadian Prairies reveals seasonal differences in the underlying coupling mechanism. During spring and fall, as opposed to summer, the interactive soil moisture phase impacts the snow depth and surface albedo, which further impacts the surface energy budget and thus the surface air temperature; the air temperature then influences the snow depth in a feedback loop. Projected changes to coupling are also season specific: relatively drier soil conditions strengthen coupling during summer, while changes in soil moisture phase, snow depth, and cloud cover impact coupling during colder months. Furthermore, results demonstrate that soil moisture variability amplifies the frequency of temperature extremes over regions of strong coupling in current and future climates.
Surface-water-quality assessment of the Yakima River basin, Washington; project description
McKenzie, S.W.; Rinella, J.F.
1987-01-01
In April 1986, the U.S. Geological Survey began the National Water Quality Assessment program to: (1) provide a nationally consistent description of the current status of water quality, (2) define water quality trends that have occurred over recent decades, and (3) relate past and present water quality conditions to relevant natural features, the history of land and water use, and land management and waste management practices. At present (1987), The National Water Quality Assessment program is in a pilot studies phase, in which assessment concepts and approaches are being tested and modified to prepare for possible full implementation of the program. Seven pilot projects (four surface water projects and three groundwater projects) have been started. The Yakima River basin in Washington is one of the pilot surface water project areas. The Yakima River basin drains in area of 6,155 sq mi and contains about 1,900 river mi of perennial streams. Major land use activities include growing and harvesting timber, dryland pasture grazing, intense farming and irrigated agriculture, and urbanization. Water quality issues that result from these land uses include potentially large concentrations of suspended sediment, bacteria, nutrients, pesticides, and trace elements that may affect water used for human consumption, fish propagation and passage, contact recreation, livestock watering, and irrigation. Data will be collected in a nine year cycle. The first three years of the cycle will be a period of concentrated data acquisition and interpretation. For the next six years, sample collection will be done at a much lower level of intensity to document the occurrence of any gross changes in water quality. This nine year cycle would then be repeated. Three types of sampling activities will be used for data acquisition: fixed location station sampling, synoptic sampling, and intensive reach studies. (Lantz-PTT)
NASA Astrophysics Data System (ADS)
Achutarao, K. M.; Singh, R.
2017-12-01
There are various sources of uncertainty in model projections of future climate change. These include differences in the formulation of climate models, internal variability, and differences in scenarios. Internal variability in a climate system represents the unforced change due to the chaotic nature of the climate system and is considered irreducible (Deser et al., 2012). Internal variability becomes important at regional scales where it can dominate forced changes. Therefore it needs to be carefully assessed in future projections. In this study we segregate the role of internal variability in the future temperature and precipitation projections over the Indian region. We make use of the Coupled Model Inter-comparison Project - phase 5 (CMIP5; Taylor et al., 2012) database containing climate model simulations carried out by various modeling centers around the world. While the CMIP5 experimental protocol recommended producing numerous ensemble members, only a handful of the modeling groups provided multiple realizations. Having a small number of realizations is a limitation in producing a quantification of internal variability. We therefore exploit the Community Earth System Model Large Ensemble (CESM-LE; Kay et al., 2014) dataset which contains a 40 member ensemble of a single model- CESM1 (CAM5) to explore the role of internal variability in Future Projections. Surface air temperature and precipitation change projections over regional and sub-regional scale are analyzed under the IPCC emission scenario (RCP8.5) for different seasons and homogeneous climatic zones over India. We analyze the spread in projections due to internal variability in the CESM-LE and CMIP5 datasets over these regions.
Free-Piston Stirling Power Conversion Unit for Fission Surface Power, Phase I Final Report
NASA Technical Reports Server (NTRS)
Wood, J. Gary; Buffalino, Andrew; Holliday, Ezekiel; Penswick, Barry; Gedeon, David
2010-01-01
This report summarizes the design of a 12 kW dual opposed free-piston Stirling convertor and controller for potential future use in space missions. The convertor is heated via a pumped NaK loop and cooling is provided by a pumped water circuit. Convertor efficiency is projected at 27 percent (AC electrical out/heat in). The controller converts the AC electrical output to 120 Vdc and is projected at 91 percent efficiency. A mechanically simple arrangement, based on proven technology, was selected in which the piston is resonated almost entirely by the working space pressure swing, while the displacer is resonated by planar mechanical springs in the bounce space.
Robotic Lunar Lander Development Project Status
NASA Technical Reports Server (NTRS)
Hammond, Monica; Bassler, Julie; Morse, Brian
2010-01-01
This slide presentation reviews the status of the development of a robotic lunar lander. The goal of the project is to perform engineering tests and risk reduction activities to support the development of a small lunar lander for lunar surface science. This includes: (1) risk reduction for the flight of the robotic lander, (i.e., testing and analyzing various phase of the project); (2) the incremental development for the design of the robotic lander, which is to demonstrate autonomous, controlled descent and landing on airless bodies, and design of thruster configuration for 1/6th of the gravity of earth; (3) cold gas test article in flight demonstration testing; (4) warm gas testing of the robotic lander design; (5) develop and test landing algorithms; (6) validate the algorithms through analysis and test; and (7) tests of the flight propulsion system.
Projection Moire measurement of the deflection of composite plates subject to bird strike impact
NASA Astrophysics Data System (ADS)
Shulev, A.; Van Paepegem, W.; Harizanova, J.; Moentjens, A.; Degrieck, J.; Sainov, V.
2007-06-01
For the new generation aircraft families, the use of fibre-reinforced plastics is considered for the leading edge of the wings. However, this leading edge is very prone to bird strike impact. This paper presents the use of the projection moire technique to measure the out-of-plane deflections of composite plates subject to bird strike. Very strict constraints with regard to: (i) high speed image acquisition, (ii) vibrations of the impact chamber, and (iii) projection and observation angles - complicated substantially the development of the set-up. Moreover, the high frame rates (12000 fps) required a very intensive illumination. In the optimized configuration, a specially designed grating with gradually changing period is projected by means of special Metal Hydride lamps through one of the side windows of the impact chamber onto the composite plate riveted in a steel frame. The digital high speed camera is mounted on the roof of the impact chamber and records through a mirror the object surface with the projected fringe pattern on it. Numerical routines based on Local Fourier Transform were developed to process the digital images, to extract the phase and the out-of-plane displacements. The phase evaluation is possible due to the carrier frequency nature of the projected moire pattern. This carrier frequency allows separation of the unwanted additive and multiplicative fringe pattern components in the frequency domain via the application of a proper mask. The numerical calculations were calibrated for the bird strike of an aluminium plate, where the plastic deformation could be checked after the test.
Implementing Effective Mission Systems Engineering Practices During Early Project Formulation Phases
NASA Technical Reports Server (NTRS)
Moton, Tryshanda
2016-01-01
Developing and implementing a plan for a NASA space mission can be a complicated process. The needs, goals, and objectives of any proposed mission or technology must be assessed early in the Project Life Cycle. The key to successful development of a space mission or flight project is the inclusion of systems engineering in early project formulation, namely during Pre-phase A, Phase A, and Phase B of the NASA Project Life Cycle. When a space mission or new technology is in pre-development, or "pre-Formulation", feasibility must be determined based on cost, schedule, and risk. Inclusion of system engineering during project formulation is key because in addition to assessing feasibility, design concepts are developed and alternatives to design concepts are evaluated. Lack of systems engineering involvement early in the project formulation can result in increased risks later in the implementation and operations phases of the project. One proven method for effective systems engineering practice during the pre-Formulation Phase is the use of a mission conceptual design or technology development laboratory, such as the Mission Design Lab (MDL) at NASA's Goddard Space Flight Center (GSFC). This paper will review the engineering process practiced routinely in the MDL for successful mission or project development during the pre-Formulation Phase.
Observation of an Opposition Surge on Triton
NASA Astrophysics Data System (ADS)
Herbert, B. D.; Buratti, B. J.; Schmidt, B.; Bauer, J. M.; Hicks, M. D.
2004-11-01
Ground-based observations of Neptune's moon Triton taken during the summers of 2000, 2003, and 2004 show a rotational light curve with a large amplitude. This is in stark contrast to data from the 1989 Voyager II flyby, which implies significant changes have occurred on Triton's surface since that time. The light curve has two notable regions, one that is significantly brighter than was observed in 1989 and one that is significantly darker. Data were also taken at a broad range of solar phase angles, allowing for a comprehensive study of the effects of phase on Triton's brightness. Analysis of the phase curve yields a solar phase coefficient close to zero for phases greater than 0.08 degrees, a number in close agreement with past studies that focused on higher phase angles. We also report a previously unrecognized opposition surge. Preliminary analysis suggests that the surge has different characteristics in the dark and bright regions currently visible on Triton, implying a non-homogenous regolith. Funding for this project was provided in part by the New York Space Grant Consortium and the NASA Undergraduate Student Research Program.
Composite, ordered material having sharp surface features
D'Urso, Brian R.; Simpson, John T.
2006-12-19
A composite material having sharp surface features includes a recessive phase and a protrusive phase, the recessive phase having a higher susceptibility to a preselected etchant than the protrusive phase, the composite material having an etched surface wherein the protrusive phase protrudes from the surface to form a sharp surface feature. The sharp surface features can be coated to make the surface super-hydrophobic.
Spin Bose-metal phase in a spin- (1)/(2) model with ring exchange on a two-leg triangular strip
NASA Astrophysics Data System (ADS)
Sheng, D. N.; Motrunich, Olexei I.; Fisher, Matthew P. A.
2009-05-01
Recent experiments on triangular lattice organic Mott insulators have found evidence for a two-dimensional (2D) spin liquid in close proximity to the metal-insulator transition. A Gutzwiller wave function study of the triangular lattice Heisenberg model with a four-spin ring exchange term appropriate in this regime has found that the projected spinon Fermi sea state has a low variational energy. This wave function, together with a slave particle-gauge theory analysis, suggests that this putative spin liquid possesses spin correlations that are singular along surfaces in momentum space, i.e., “Bose surfaces.” Signatures of this state, which we will refer to as a “spin Bose metal” (SBM), are expected to manifest in quasi-one-dimensional (quasi-1D) ladder systems: the discrete transverse momenta cut through the 2D Bose surface leading to a distinct pattern of 1D gapless modes. Here, we search for a quasi-1D descendant of the triangular lattice SBM state by exploring the Heisenberg plus ring model on a two-leg triangular strip (zigzag chain). Using density matrix renormalization group (DMRG) supplemented by variational wave functions and a bosonization analysis, we map out the full phase diagram. In the absence of ring exchange the model is equivalent to the J1-J2 Heisenberg chain, and we find the expected Bethe-chain and dimerized phases. Remarkably, moderate ring exchange reveals a new gapless phase over a large swath of the phase diagram. Spin and dimer correlations possess singular wave vectors at particular “Bose points” (remnants of the 2D Bose surface) and allow us to identify this phase as the hoped for quasi-1D descendant of the triangular lattice SBM state. We use bosonization to derive a low-energy effective theory for the zigzag spin Bose metal and find three gapless modes and one Luttinger parameter controlling all power law correlations. Potential instabilities out of the zigzag SBM give rise to other interesting phases such as a period-3 valence bond solid or a period-4 chirality order, which we discover in the DMRG. Another interesting instability is into a spin Bose-metal phase with partial ferromagnetism (spin polarization of one spinon band), which we also find numerically using the DMRG.
Vermeul, Vince R.; Strickland, Chris E.; Thorne, Paul D.; ...
2014-12-31
The FutureGen 2.0 Project will design and build a first-of-its-kind, near-zero emissions coal-fueled power plant with carbon capture and storage (CCS). To assess storage site performance and meet the regulatory requirements of the Class VI Underground Injection Control (UIC) Program for CO2 Geologic Sequestration, the FutureGen 2.0 project will implement a suite of monitoring technologies designed to 1) evaluate CO2 mass balance and 2) detect any unforeseen loss in CO2 containment. The monitoring program will include direct monitoring of the injection stream and reservoir, and early-leak-detection monitoring directly above the primary confining zone. It will also implement an adaptive monitoringmore » strategy whereby monitoring results are continually evaluated and the monitoring network is modified as required, including the option to drill additional wells in out-years. Wells will be monitored for changes in CO2 concentration and formation pressure, and other geochemical/isotopic signatures that provide indication of CO2 or brine leakage. Indirect geophysical monitoring technologies that were selected for implementation include passive seismic, integrated surface deformation, time-lapse gravity, and pulsed neutron capture logging. Near-surface monitoring approaches that have been initiated include surficial aquifer and surface- water monitoring, soil-gas monitoring, atmospheric monitoring, and hyperspectral data acquisition for assessment of vegetation conditions. Initially, only the collection of baseline data sets is planned; the need for additional near- surface monitoring will be continually evaluated throughout the design and operational phases of the project, and selected approaches may be reinstituted if conditions warrant. Given the current conceptual understanding of the subsurface environment, early and appreciable impacts to near-surface environments are not expected.« less
Phase-stepped fringe projection by rotation about the camera's perspective center.
Huddart, Y R; Valera, J D; Weston, N J; Featherstone, T C; Moore, A J
2011-09-12
A technique to produce phase steps in a fringe projection system for shape measurement is presented. Phase steps are produced by introducing relative rotation between the object and the fringe projection probe (comprising a projector and camera) about the camera's perspective center. Relative motion of the object in the camera image can be compensated, because it is independent of the distance of the object from the camera, whilst the phase of the projected fringes is stepped due to the motion of the projector with respect to the object. The technique was validated with a static fringe projection system by moving an object on a coordinate measuring machine (CMM). The alternative approach, of rotating a lightweight and robust CMM-mounted fringe projection probe, is discussed. An experimental accuracy of approximately 1.5% of the projected fringe pitch was achieved, limited by the standard phase-stepping algorithms used rather than by the accuracy of the phase steps produced by the new technique.
DOT National Transportation Integrated Search
2016-03-07
Building on the success of developing a UAV based unpaved road assessment system in Phase I, the project team was awarded a Phase II project by the USDOT to focus on outreach and implementation. The project team added Valerie Lefler of Integrated Glo...
1990-01-01
EXCELLENT DIELECTRIC PROPERTIES AND HIGH THERMAL CONDUCTIVITY. ASSUMING A GLASS -EPOXY DIELECTRIC, THE PWB THERMAL EXPANSION MUST BE MATCHED TO CHIP AND CASE...OF A GLASS FIBER-REINFORCED POLYMERIC RESIN AND IS PROJECTED TO REDUCE THE WEIGHT OF THE CARTRIDGE CASE ALONE BY 67%. THE TOTAL M855 CARTRIDGE WOULD...SENSOR DESIGN UTILIZES SURFACE PLASMON POLARITON(SPPs), TWO-DIMENSIONAL ELECTROGMAGNETIC WAVES GENERATED AT A METAL- GLASS BOUNDARY BY TAKING ENERGY FROM
High dynamic range fringe acquisition: A novel 3-D scanning technique for high-reflective surfaces
NASA Astrophysics Data System (ADS)
Jiang, Hongzhi; Zhao, Huijie; Li, Xudong
2012-10-01
This paper presents a novel 3-D scanning technique for high-reflective surfaces based on phase-shifting fringe projection method. High dynamic range fringe acquisition (HDRFA) technique is developed to process the fringe images reflected from the shiny surfaces, and generates a synthetic fringe image by fusing the raw fringe patterns, acquired with different camera exposure time and the illumination fringe intensity from the projector. Fringe image fusion algorithm is introduced to avoid saturation and under-illumination phenomenon by choosing the pixels in the raw fringes with the highest fringe modulation intensity. A method of auto-selection of HDRFA parameters is developed and largely increases the measurement automation. The synthetic fringes have higher signal-to-noise ratio (SNR) under ambient light by optimizing HDRFA parameters. Experimental results show that the proposed technique can successfully measure objects with high-reflective surfaces and is insensitive to ambient light.
The relationship between interannual and long-term cloud feedbacks
Zhou, Chen; Zelinka, Mark D.; Dessler, Andrew E.; ...
2015-12-11
The analyses of Coupled Model Intercomparison Project phase 5 simulations suggest that climate models with more positive cloud feedback in response to interannual climate fluctuations also have more positive cloud feedback in response to long-term global warming. Ensemble mean vertical profiles of cloud change in response to interannual and long-term surface warming are similar, and the ensemble mean cloud feedback is positive on both timescales. However, the average long-term cloud feedback is smaller than the interannual cloud feedback, likely due to differences in surface warming pattern on the two timescales. Low cloud cover (LCC) change in response to interannual andmore » long-term global surface warming is found to be well correlated across models and explains over half of the covariance between interannual and long-term cloud feedback. In conclusion, the intermodel correlation of LCC across timescales likely results from model-specific sensitivities of LCC to sea surface warming.« less
Progress in standoff surface contaminant detector platform
NASA Astrophysics Data System (ADS)
Dupuis, Julia R.; Giblin, Jay; Dixon, John; Hensley, Joel; Mansur, David; Marinelli, William J.
2017-05-01
Progress towards the development of a longwave infrared quantum cascade laser (QLC) based standoff surface contaminant detection platform is presented. The detection platform utilizes reflectance spectroscopy with application to optically thick and thin materials including solid and liquid phase chemical warfare agents, toxic industrial chemicals and materials, and explosives. The platform employs an ensemble of broadband QCLs with a spectrally selective detector to interrogate target surfaces at 10s of m standoff. A version of the Adaptive Cosine Estimator (ACE) featuring class based screening is used for detection and discrimination in high clutter environments. Detection limits approaching 0.1 μg/cm2 are projected through speckle reduction methods enabling detector noise limited performance. The design, build, and validation of a breadboard version of the QCL-based surface contaminant detector are discussed. Functional test results specific to the QCL illuminator are presented with specific emphasis on speckle reduction.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhou, Chen; Zelinka, Mark D.; Dessler, Andrew E.
The analyses of Coupled Model Intercomparison Project phase 5 simulations suggest that climate models with more positive cloud feedback in response to interannual climate fluctuations also have more positive cloud feedback in response to long-term global warming. Ensemble mean vertical profiles of cloud change in response to interannual and long-term surface warming are similar, and the ensemble mean cloud feedback is positive on both timescales. However, the average long-term cloud feedback is smaller than the interannual cloud feedback, likely due to differences in surface warming pattern on the two timescales. Low cloud cover (LCC) change in response to interannual andmore » long-term global surface warming is found to be well correlated across models and explains over half of the covariance between interannual and long-term cloud feedback. In conclusion, the intermodel correlation of LCC across timescales likely results from model-specific sensitivities of LCC to sea surface warming.« less
Ground Plane and Near-Surface Thermal Analysis for NASA's Constellation Program
NASA Technical Reports Server (NTRS)
Gasbarre, Joseph F.; Amundsen, Ruth M.; Scola, Salvatore; Leahy, Frank F.; Sharp, John R.
2008-01-01
Most spacecraft thermal analysis tools assume that the spacecraft is in orbit around a planet and are designed to calculate solar and planetary fluxes, as well as radiation to space. On NASA Constellation projects, thermal analysts are also building models of vehicles in their pre-launch condition on the surface of a planet. This process entails making some modifications in the building and execution of a thermal model such that the radiation from the planet, both reflected albedo and infrared, is calculated correctly. Also important in the calculation of pre-launch vehicle temperatures are the natural environments at the vehicle site, including air and ground temperatures, sky radiative background temperature, solar flux, and optical properties of the ground around the vehicle. A group of Constellation projects have collaborated on developing a cohesive, integrated set of natural environments that accurately capture worst-case thermal scenarios for the pre-launch and launch phases of these vehicles. The paper will discuss the standardization of methods for local planet modeling across Constellation projects, as well as the collection and consolidation of natural environments for launch sites. Methods for Earth as well as lunar sites will be discussed.
Acoustic Holography of the Solar Convection Zone with SOHO-MDI Observations
NASA Technical Reports Server (NTRS)
Lindsey, Charles
2005-01-01
The original grant with the title stated above was NAG5-10984, awarded to the Solar Physics Research Corporation (SPRC) in July, 2001, and was to be a three-year project. The basic theme of the project was the development and application of computational seismic holography for imaging, diagnostics, and monitoring of magnetic anomalies beneath active regions, in the deep solar interior, and on the Sun's far surface. The project was roughly separated into the following five tasks: (1) A holographic survey of active regions. (2) p-Mode absorption diagnostics of magnetic regions. (3) Acoustic modeling of the shallow subphotospheres of active regions and the quiet-Sun supergranulation based on phase-correlation seismic holography. (4) Seismic holography of the deep convection zone. (5) Improvements in holographic imaging of the far surface of the Sun. Following the death of Karen Harvey, President of SPRC, during the first year, the grant was transferred to Northwest Research Associates as NAG5-12901. Substantial but progress had been made on most of the above tasks in the first year under NAG5-10984, but none were completed. This work was continued under NAG5-12901.
Kotake, Shigeru; Nanke, Yuki; Yago, Toru; Kawamoto, Manabu; Kobashigawa, Tsuyoshi; Yamanaka, Hisashi
2016-01-01
Rheumatoid arthritis (RA) is a systemic autoimmune disease with chronic joint inflammation characterized by activated T cells. IL-17 and Th17 cells play important roles in the pathogenesis of RA. Recently, plasticity in helper T cells has been demonstrated; Th17 cells can convert to Th1 cells. However, it remains to be elucidated whether this conversion occurs in the early phase of RA. Here, we validated the methods of the Human Immunology Project using only the cell-surface marker through measuring the actual expression of IL-17 and IFNγ. We also evaluated the expression of CD161 in human Th17 cells. We then tried to identify Th17 cells, IL-17(+)Th17 cells, and IFNγ (+)Th17 cells in the peripheral blood of early-onset RA patients using the standardized method of the Human Immunology Project. Our findings validated the method and the expression of CD161. The ratio of IFNγ (+)Th17 cells in memory T cells was inversely correlated to the titers of anti-CCP antibodies in the early-onset RA patients. These findings suggest that Th17 cells play important roles in the early phase of RA and that anti-IL-17 antibodies should be administered to patients with early phase RA, especially those with high titers of CCP antibodies.
Kotake, Shigeru; Nanke, Yuki; Yago, Toru; Kawamoto, Manabu; Kobashigawa, Tsuyoshi; Yamanaka, Hisashi
2016-01-01
Rheumatoid arthritis (RA) is a systemic autoimmune disease with chronic joint inflammation characterized by activated T cells. IL-17 and Th17 cells play important roles in the pathogenesis of RA. Recently, plasticity in helper T cells has been demonstrated; Th17 cells can convert to Th1 cells. However, it remains to be elucidated whether this conversion occurs in the early phase of RA. Here, we validated the methods of the Human Immunology Project using only the cell-surface marker through measuring the actual expression of IL-17 and IFNγ. We also evaluated the expression of CD161 in human Th17 cells. We then tried to identify Th17 cells, IL-17+Th17 cells, and IFNγ +Th17 cells in the peripheral blood of early-onset RA patients using the standardized method of the Human Immunology Project. Our findings validated the method and the expression of CD161. The ratio of IFNγ +Th17 cells in memory T cells was inversely correlated to the titers of anti-CCP antibodies in the early-onset RA patients. These findings suggest that Th17 cells play important roles in the early phase of RA and that anti-IL-17 antibodies should be administered to patients with early phase RA, especially those with high titers of CCP antibodies. PMID:27294146
Norrman, Jenny; Volchko, Yevheniya; Hooimeijer, Fransje; Maring, Linda; Kain, Jaan-Henrik; Bardos, Paul; Broekx, Steven; Beames, Alistair; Rosén, Lars
2016-09-01
This paper presents a holistic approach to sustainable urban brownfield redevelopment where specific focus is put on the integration of a multitude of subsurface qualities in the early phases of the urban redevelopment process, i.e. in the initiative and plan phases. Achieving sustainability in brownfield redevelopment projects may be constrained by a failure of engagement between two key expert constituencies: urban planners/designers and subsurface engineers, leading to missed opportunities and unintended outcomes in the plan realisation phase. A more integrated approach delivers greater benefits. Three case studies in the Netherlands, Belgium and Sweden were used to test different sustainability assessment instruments in terms of the possibility for knowledge exchange between the subsurface and the surface sectors and in terms of cooperative learning among experts and stakeholders. Based on the lessons learned from the case studies, a generic decision process framework is suggested that supports holistic decision making. The suggested framework focuses on stakeholder involvement, communication, knowledge exchange and learning and provides an inventory of instruments that can support these processes. Copyright © 2016 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sherman, Andrew J
A heterogeneous body having ceramic rich cermet regions in a more ductile metal matrix. The heterogeneous bodies are formed by thermal spray operations on metal substrates. The thermal spray operations apply heat to a cermet powder and project it onto a solid substrate. The cermet powder is composed of complex composite particles in which a complex ceramic-metallic core particle is coated with a matrix precursor. The cermet regions are generally comprised of complex ceramic-metallic composites that correspond approximately to the core particles. The cermet regions are approximately lenticular shaped with an average width that is at least approximately twice themore » average thickness. The cermet regions are imbedded within the matrix phase and generally isolated from one another. They have obverse and reverse surfaces. The matrix phase is formed from the matrix precursor coating on the core particles. The amount of heat applied during the formation of the heterogeneous body is controlled so that the core particles soften but do not become so fluid that they disperse throughout the matrix phase. The force of the impact on the surface of the substrate tends to flatten them. The flattened cermet regions tend to be approximately aligned with one another in the body.« less
Additive Manufacturing of Wind Turbine Molds
DOE Office of Scientific and Technical Information (OSTI.GOV)
Post, Brian; Richardson, Bradley; Lloyd, Peter
The objective of this project was to explore the utility of Big Area Additive Manufacturing (BAAM) for low cost manufacturing of wind turbine molds. Engineers at Oak Ridge National Laboratory (ORNL) and TPI Composites (TPI) collaborated to design and manufacture a printed mold that can be used for resin infusion of wind turbine components. Specific focus was on required material properties (operating temperatures and pressures, coefficient of thermal expansion (CTE), thermal conductivity), surface finish (accuracy and coatings) and system integration (integrated vacuum ports, and heating element). The project began with a simple proof of principle components, targeting surface coatings andmore » material properties for printing a small section (approximately 4’ x 4’ x 2’) of a mold. Next, the second phase scaled up and integrated with the objective of capturing all of the necessary components (integrated heating to accelerate cure time, and vacuum, sealing) for resin infusion on a mold of significant size (8’ x 20’ x 6’).« less
NASA Technical Reports Server (NTRS)
Purgold, Gerald C.; Wheeler, Robert J.; Whitlock, Charles H.
1992-01-01
Tables and figures are presented which show local site observations of cloud fractions, the number of cloud layers, direction of movement, and precipitation data collected during the FIRE (First ISCCP Regional Experiment) Phase 2 Cirrus Intensive Field Observations (IFO) conducted in Coffeyville, Kansas during November and December, 1991. Selected data are also presented at the times of the TIROS Operational Vertical Sounder (TOVS) satellite overpass. Several major scientific projects have used surface-based observations of clouds to compare directly with those being observed from satellites. Characterizing the physical properties of clouds is extremely useful in obtaining a more accurate analysis of the effect of clouds and their movements on weather and climate. It is the purpose of this paper to report data collected during the FIRE Phase 2 IFO experiment and to provide a brief history of such a surface-based system and the technical information required for recording local cloud parameters.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Laura J. Pyrak-Nolte; Nicholas J. Giordano; David D. Nolte
2004-03-01
The principal challenge of upscaling techniques for multi-phase fluid dynamics in porous media is to determine which properties on the micro-scale can be used to predict macroscopic flow and spatial distribution of phases at core- and field-scales. The most notable outcome of recent theories is the identification of interfacial areas per volume for multiple phases as a fundamental parameter that determines much of the multi-phase properties of the porous medium. A formal program of experimental research was begun to directly test upscaling theories in fluid flow through porous media by comparing measurements of relative permeability and capillary-saturation with measurements ofmore » interfacial area per volume. This project on the experimental investigation of relative permeability upscaling has produced a unique combination of three quite different technical approaches to the upscaling problem of obtaining pore-related microscopic properties and using them to predict macroscopic behavior. Several important ''firsts'' have been achieved during the course of the project. (1) Optical coherence imaging, a laser-based ranging and imaging technique, has produced the first images of grain and pore structure up to 1 mm beneath the surface of the sandstone and in a laboratory borehole. (2) Woods metal injection has connected for the first time microscopic pore-scale geometric measurements with macroscopic saturation in real sandstone cores. (3) The micro-model technique has produced the first invertible relationship between saturation and capillary pressure--showing that interfacial area per volume (IAV) provides the linking parameter. IAV is a key element in upscaling theories, so this experimental finding may represent the most important result of this project, with wide ramifications for predictions of fluid behavior in porous media.« less
NASA Astrophysics Data System (ADS)
Wang, Jia; Guo, Zhenyan; Song, Yang; Han, Jun
2018-01-01
To realize volume moiré tomography (VMT) for the real three-dimensional (3D) diagnosis of combustion fields, according to 3D filtered back projection (FBP) reconstruction algorithm, the radial derivatives of the projected phase should be measured firstly. In this paper, a simple spatial phase-shifting moiré deflectometry with double cross gratings is presented to measure the radial first-order derivative of the projected phase. Based on scalar diffraction theory, the explicit analytical intensity distributions of moiré patterns on different diffracted orders are derived, and the spatial shifting characteristics are analyzed. The results indicate that the first-order derivatives of the projected phase in two mutually perpendicular directions are involved in moiré patterns, which can be combined to compute the radial first-order derivative. And multiple spatial phase-shifted moiré patterns can be simultaneously obtained; the phase-shifted values are determined by the parameters of the system. A four-step phase-shifting algorithm is proposed for phase extraction, and its accuracy is proved by numerical simulations. Finally, the moiré deflectometry is used to measure the radial first-order derivative of projected phase of a propane flame with plane incident wave, and the 3D temperature distribution is reconstructed.
ERIC Educational Resources Information Center
Meyer, Angela Osterman; Mon, Manuel J.; Hibbard, Susan T.
2011-01-01
We present our Lunar Phases Project, an ongoing effort utilizing students' actual observations within a mental model building framework to improve student understanding of the causes and process of the lunar phases. We implement this project with a sample of undergraduate, nonscience major students enrolled in a midsized public university located…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Advanced Resources International
2010-01-31
Within the Southwest Regional Partnership on Carbon Sequestration (SWP), three demonstrations of geologic CO{sub 2} sequestration are being performed -- one in an oilfield (the SACROC Unit in the Permian basin of west Texas), one in a deep, unmineable coalbed (the Pump Canyon site in the San Juan basin of northern New Mexico), and one in a deep, saline reservoir (underlying the Aneth oilfield in the Paradox basin of southeast Utah). The Pump Canyon CO{sub 2}-enhanced coalbed methane (CO{sub 2}/ECBM) sequestration demonstration project plans to demonstrate the effectiveness of CO{sub 2} sequestration in deep, unmineable coal seams via a small-scalemore » geologic sequestration project. The site is located in San Juan County, northern New Mexico, just within the limits of the high-permeability fairway of prolific coalbed methane production. The study area for the SWP project consists of 31 coalbed methane production wells located in a nine section area. CO{sub 2} was injected continuously for a year and different monitoring, verification and accounting (MVA) techniques were implemented to track the CO{sub 2} movement inside and outside the reservoir. Some of the MVA methods include continuous measurement of injection volumes, pressures and temperatures within the injection well, coalbed methane production rates, pressures and gas compositions collected at the offset production wells, and tracers in the injected CO{sub 2}. In addition, time-lapse vertical seismic profiling (VSP), surface tiltmeter arrays, a series of shallow monitoring wells with a regular fluid sampling program, surface measurements of soil composition, CO{sub 2} fluxes, and tracers were used to help in tracking the injected CO{sub 2}. Finally, a detailed reservoir model was constructed to help reproduce and understand the behavior of the reservoir under production and injection operation. This report summarizes the different phases of the project, from permitting through site closure, and gives the results of the different MVA techniques.« less
NASA Astrophysics Data System (ADS)
Poulet, Francois; Carter, John; Riu, Lucie; Martinez, Antoine; Bibring, Jean-Pierre; Gondet, Brigitte; Langevin, Yves
2017-10-01
An essential part of revealing the past conditions that occurred at the surface of Mars is determining its mineralogy. Igneous compositions can provide insight into mechanisms such as crustal formation, magma differentiation and volcanic activity, while clays, salts and other altered phases can constrain the past liquid water environments on/near the surface. The visible near-infrared imaging spectrometer OMEGA on board the ESA Mars Express mission provided major steps in our understanding of the composition of the Martian surface by mapping anhydrous and hydrated minerals (Riu et al. 2017; Carter et al. 2017). The ultimate step in interpreting IR OMEGA data is a quantitative retrieval of mineral abundances from the modeling of spectra of selected terrains. So far, such an approach was performed on restricted areas of the surface using a radiative transfer model (Poulet et al., 2009, 2014). The purpose of the M3 (Modal Mineralogy of Mars) project is thus to provide global distributions of Martian surface minerals using previous OMEGA investigations, and to distribute the mineral maps to the science community through the web portal PSUP (Poulet et al. 2017). Two types of terrains are considered: type 1: mafic-bearing ones; type 2: hydrated deposits.For type-1 terrains, a 3-D global image cube was constructed containing atmospheric- and aerosol-corrected NIR spectra distributed over 32px/° and +/-60° of latitude with a surface coverage of 90%. NIR reflectance spectra were modeled to retrieve mineral abundances and particle grain sizes of the mafic-bearing terrains. This work is completed with final maps presented this year (Riu et al. 2017).For type-2 terrains, a specific approach is required. First, signatures of hydrated minerals are detected for each single OMEGA cube. Second, the spectral modeling is applied to each pixel and then the modeled abundances are averaged when overlapping observations occur for a specific location. The validation of this approach has been performed on two regions that exhibit the greatest mineral diversity of hydrated minerals on Mars: Nilo-Syrtis region and Mawrth Vallis/Oxia Planum region. Mineral maps of various hydrated and primary phases will be presented.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pelliccia, Daniele; Vaz, Raquel; Svalbe, Imants
X-ray imaging of soft tissue is made difficult by their low absorbance. The use of x-ray phase imaging and tomography can significantly enhance the detection of these tissues and several approaches have been proposed to this end. Methods such as analyzer-based imaging or grating interferometry produce differential phase projections that can be used to reconstruct the 3D distribution of the sample refractive index. We report on the quantitative comparison of three different methods to obtain x-ray phase tomography with filtered back-projection from differential phase projections in the presence of noise. The three procedures represent different numerical approaches to solve themore » same mathematical problem, namely phase retrieval and filtered back-projection. It is found that obtaining individual phase projections and subsequently applying a conventional filtered back-projection algorithm produces the best results for noisy experimental data, when compared with other procedures based on the Hilbert transform. The algorithms are tested on simulated phantom data with added noise and the predictions are confirmed by experimental data acquired using a grating interferometer. The experiment is performed on unstained adult zebrafish, an important model organism for biomedical studies. The method optimization described here allows resolution of weak soft tissue features, such as muscle fibers.« less
Broadband multiple responses of surface modes in quasicrystalline plasmonic structure
Yuan, Haiming; Jiang, Xiangqian; Huang, Feng; Sun, Xiudong
2016-01-01
We numerically study the multiple excitation of surface modes in 2D photonic quasicrystal/metal/substrate structure. An improved rigorous coupled wave analysis method that can handle the quasicrystalline structure is presented. The quasicrystalline lattice, which refers to Penrose tiling in this paper, is generated by the cut-and-project method. The normal incidence spectrum presents a broadband multiple responses property. We find that the phase matching condition determines the excitation frequency for a given incident angle, while the depth of the reflection valley depends on the incident polarization. The modes will split into several sub-modes at oblique incidence, which give rise to the appearance of more responses on the spectrum. PMID:27492782
Dynamic deformation inspection of a human arm by using a line-scan imaging system
NASA Astrophysics Data System (ADS)
Hu, Eryi
2009-11-01
A line-scan imaging system is used in the dynamic deformation measurement of a human arm when the muscle is contracting and relaxing. The measurement principle is based on the projection grating profilometry, and the measuring system is consisted of a line-scan CCD camera, a projector, optical lens and a personal computer. The detected human arm is put upon a reference plane, and a sinusoidal grating is projected onto the object surface and reference plane at an incidence angle, respectively. The deformed fringe pattern in the same line of the dynamic detected arm is captured by the line-scan CCD camera with free trigger model, and the deformed fringe pattern is recorded in the personal computer for processing. A fast Fourier transform combining with a filtering and spectrum shifting method is used to extract the phase information caused by the profile of the detected object. Thus, the object surface profile can be obtained following the geometric relationship between the fringe deformation and the object surface height. Furthermore, the deformation procedure can be obtained line by line. Some experimental results are presented to prove the feasibility of the inspection system.
NASA Astrophysics Data System (ADS)
Kaptay, George
2018-05-01
Nano-materials are materials with at least one nano-phase. A nano-phase is a phase with at least one of its dimensions below 100 nm. It is shown here that nano-phases have at least 1% of their atoms along their surface layer. The ratio of surface atoms is proportional to the specific surface area of the phase, defined as the ratio of its surface area to its volume. Each specific/molar property has its bulk value and its surface value for the given phase, being always different, as the energetic states of the atoms in the bulk and in the surface layer of a phase are different. The average specific/molar property of a nano-phase is modeled here as a linear combination of the bulk and surface values of the same property, scaled with the ratio of the surface atoms. That makes the performance of all nano-phases proportional to their specific surface area. As the characteristic size of the nano-phase is inversely proportional to its specific surface area, all specific/molar properties of nano-phases are inversely proportional to the characteristic size of the phase. This is applied to the size dependence of the molar Gibbs energy of the nano-phase, which appears to be in agreement with the thermodynamics of Gibbs. This agreement proves the general validity of the present model on the size dependence of the specific/molar properties of independent nano-phases. It is shown that the properties of nano-phases are different for independent nano-phases (surrounded only by their equilibrium vapor phase) and for nano-phases in multi-phase situations, such as a liquid nano-droplet in the sessile drop configuration.
Passive monitoring for near surface void detection using traffic as a seismic source
NASA Astrophysics Data System (ADS)
Zhao, Y.; Kuzma, H. A.; Rector, J.; Nazari, S.
2009-12-01
In this poster we present preliminary results based on our several field experiments in which we study seismic detection of voids using a passive array of surface geophones. The source of seismic excitation is vehicle traffic on nearby roads, which we model as a continuous line source of seismic energy. Our passive seismic technique is based on cross-correlation of surface wave fields and studying the resulting power spectra, looking for "shadows" caused by the scattering effect of a void. High frequency noise masks this effect in the time domain, so it is difficult to see on conventional traces. Our technique does not rely on phase distortions caused by small voids because they are generally too tiny to measure. Unlike traditional impulsive seismic sources which generate highly coherent broadband signals, perfect for resolving phase but too weak for resolving amplitude, vehicle traffic affords a high power signal a frequency range which is optimal for finding shallow structures. Our technique results in clear detections of an abandoned railroad tunnel and a septic tank. The ultimate goal of this project is to develop a technology for the simultaneous imaging of shallow underground structures and traffic monitoring near these structures.
NASA Technical Reports Server (NTRS)
Goodwin, P. S.; Traxler, M. R.; Meeks, W. G.; Flanagan, F. M.
1976-01-01
The overall evolution of the Helios Project is summarized from its conception through to the completion of the Helios-1 mission phase 2. Beginning with the project objectives and concluding with the Helios-1 spacecraft entering its first superior conjunction (end of mission phase 2), descriptions of the project, the mission and its phases, international management and interfaces, and Deep Space Network-spacecraft engineering development in telemetry, tracking, and command systems to ensure compatibility between the U.S. Deep Space Network and the German-built spacecraft are included.
DOT National Transportation Integrated Search
2007-12-10
The Cadastral and Right of Way Data Sharing Pilot Project is divided into three phases: Phase 1 Identify Information to Share, Phase 2 Information Collection, Phase 3 Web-based Information Access and Transfer. The Phase 1 and Phase 2 Summary Report d...
40 CFR 35.1650-1 - Project period.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Project period. 35.1650-1 Section 35... Lakes § 35.1650-1 Project period. (a) The project period for Phase 1 projects shall not exceed three years. (b) The project period for Phase 2 projects shall not exceed four years. Implementation of...
40 CFR 35.1650-1 - Project period.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 1 2014-07-01 2014-07-01 false Project period. 35.1650-1 Section 35... Lakes § 35.1650-1 Project period. (a) The project period for Phase 1 projects shall not exceed three years. (b) The project period for Phase 2 projects shall not exceed four years. Implementation of...
40 CFR 35.1650-1 - Project period.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 1 2013-07-01 2013-07-01 false Project period. 35.1650-1 Section 35... Lakes § 35.1650-1 Project period. (a) The project period for Phase 1 projects shall not exceed three years. (b) The project period for Phase 2 projects shall not exceed four years. Implementation of...
40 CFR 35.1650-1 - Project period.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 1 2012-07-01 2012-07-01 false Project period. 35.1650-1 Section 35... Lakes § 35.1650-1 Project period. (a) The project period for Phase 1 projects shall not exceed three years. (b) The project period for Phase 2 projects shall not exceed four years. Implementation of...
40 CFR 35.1650-1 - Project period.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 1 2011-07-01 2011-07-01 false Project period. 35.1650-1 Section 35... Lakes § 35.1650-1 Project period. (a) The project period for Phase 1 projects shall not exceed three years. (b) The project period for Phase 2 projects shall not exceed four years. Implementation of...
Overview of NASA's Thermal Control System Development for Exploration Project
NASA Technical Reports Server (NTRS)
Stephan, Ryan A.
2010-01-01
NASA's Constellation Program includes the Orion, Altair, and Lunar Surface Systems project offices. The first two elements, Orion and Altair, are manned space vehicles while the third element is broader and includes several sub-elements including Rovers and a Lunar Habitat. The upcoming planned missions involving these systems and vehicles include several risks and design challenges. Due to the unique thermal environment, many of these risks and challenges are associated with the vehicles' thermal control system. NASA's Exploration Systems Mission Directorate (ESMD) includes the Exploration Technology Development Program (ETDP). ETDP consists of several technology development projects. The project chartered with mitigating the aforementioned risks and design challenges is the Thermal Control System Development for Exploration Project. The risks and design challenges are addressed through a rigorous technology development process that culminates with an integrated thermal control system test. The resulting hardware typically has a Technology Readiness Level (TRL) of six. This paper summarizes the development efforts being performed by the technology development project. The development efforts involve heat acquisition and heat rejection hardware including radiators, heat exchangers, and evaporators. The project has also been developing advanced phase change material heat sinks and performing assessments for thermal control system fluids.
NASA Astrophysics Data System (ADS)
West, Michael; Gao, Wei; Grand, Stephen
2004-08-01
Body and surface wave tomography have complementary strengths when applied to regional-scale studies of the upper mantle. We present a straight-forward technique for their joint inversion which hinges on treating surface waves as horizontally-propagating rays with deep sensitivity kernels. This formulation allows surface wave phase or group measurements to be integrated directly into existing body wave tomography inversions with modest effort. We apply the joint inversion to a synthetic case and to data from the RISTRA project in the southwest U.S. The data variance reductions demonstrate that the joint inversion produces a better fit to the combined dataset, not merely a compromise. For large arrays, this method offers an improvement over augmenting body wave tomography with a one-dimensional model. The joint inversion combines the absolute velocity of a surface wave model with the high resolution afforded by body waves-both qualities that are required to understand regional-scale mantle phenomena.
Topological Nodal Cooper Pairing in Doped Weyl Metals
NASA Astrophysics Data System (ADS)
Li, Yi; Haldane, F. D. M.
2018-02-01
We generalize the concept of Berry connection of the single-electron band structure to that of a two-particle Cooper pairing state between two Fermi surfaces with opposite Chern numbers. Because of underlying Fermi surface topology, the pairing Berry phase acquires nontrivial monopole structure. Consequently, pairing gap functions have topologically protected nodal structure as vortices in the momentum space with the total vorticity solely determined by the pair monopole charge qp. The nodes of gap function behave as the Weyl-Majorana points of the Bogoliubov-de Gennes pairing Hamiltonian. Their relation with the connection patterns of the surface modes from the Weyl band structure and the Majorana surface modes inside the pairing gap is also discussed. Under the approximation of spherical Fermi surfaces, the pairing symmetry are represented by monopole harmonic functions. The lowest possible pairing channel carries angular momentum number j =|qp|, and the corresponding gap functions are holomorphic or antiholomorphic functions on Fermi surfaces. After projected on the Fermi surfaces with nontrivial topology, all the partial-wave channels of pairing interactions acquire the monopole charge qp independent of concrete pairing mechanism.
The NEOShield-2 EU Project - The first year of the Italian contribution
NASA Astrophysics Data System (ADS)
Ieva, Simone; Dotto, Elisabetta; Mazzotta Epifani, Elena; Di Paola, Andrea; Speziali, Roberto; Lazzarin, Monica; Bertini, Ivano; Barucci, Maria Antonieta; Perna, Davide; Lazzaro, Daniela; Silva, Sergio; Monteiro, Filipe; Perozzi, Ettore; Micheli, Marco; Cortese, Matteo
2016-10-01
The population of Near Earth Asteroids (NEAs) is responsible for a continuous flux of impactors with our planet. To date, more than 14500 NEAs are known, with a current discovery rate of ˜1500 objects/year.The NEA population show a great diversity in terms of composition and physical properties: (different shapes, rotational states, rotational periods...). NEA diversity is also emphasized by the different taxonomic types found within the population that give some hints about the NEA surface composition.The study of their physical nature is compelling in view of the potential hazard posed to our planet, since it has been acknowledged that whatever the mitigation scenario, it strongly depends upon the composition of the impactor. Unfortunately, only less than 15% of them have been physically characterized, and at the current discovery rate the situation is becoming progressively worse.Within the framework of the Horizon 2020 program, the European Commission promoted the study of NEAs by approving and financing the NEOShield-2 project (2015-2017). One of the main aims of the NEOShield-2 project is to undertake an extensive observational campaign to provide physical and compositional characterization of a large number of NEAs in the 50-300 m size range.INAF-OAR and Padova University, the Italian contributors to the NEOShield-2 project, are responsible for the Task 10.2.1 'Colours and Phase function', with the aim to acquire photometric measurements for a wide sample of NEOs. An operational interface is maintained together with the ESA SSA-NEO Coordination Centre (NEOCC) in order to optimize observations devoted to physical characterization.We will present the results of the first year of the Italian contribution to the project on i) phase function analysis, ii) surface colors and iii) preliminary taxonomical classification and the statistical analysis of the data obtained from several telescopes around the world.This research has been funded with support from the European Commission (grant agreement no: 640351 H2020- PROTEC-2014 - Access technologies and characterisation for Near Earth Objects (NEOs).
Project: MOBILITY. Introduction and Summary.
ERIC Educational Resources Information Center
Fresno City Coll., CA.
This report summarizes a project designed to develop vocational educational programs and services for educationally disadvantaged and physically handicapped students at Fresno City College, California. The introduction provides an overview of the two phases of the project: phase I, a needs assessment; and phase II, curriculum development and…
Evaluation of waste concrete road materials for use in oyster aquaculture - Phase 3.
DOT National Transportation Integrated Search
2016-08-01
This project was the final phase of a three-phase project. The primary objective was to determine the suitability of recycled concrete aggregate (RCA) from road projects as a bottom conditioning material for on-bottom oyster aquaculture in the Chesap...
Fountoulakis, I; Bais, A F
2015-07-01
Simulations of the monthly mean noon UV index and the effective dose for the production of vitamin D in the human skin have been performed for local noon for the latitude band 55°N-85°N using a radiative transfer model. The magnitude and spatial distribution of the changes estimated for the two quantities between the past (1955-1965 mean), the present (2010-2020 mean) and the future (2085-2095 mean) are discussed and the main drivers for these changes are identified. The irradiance simulations are based on simulations and projections of total ozone, surface reflectivity and aerosol optical depth derived from models used in the fifth phase of the Coupled Model Intercomparison Project (CMIP-5). The cloud modification factor is also derived from the CMIP-5 models and used to account for the effects of cloudiness. Simulations have been derived for two socioeconomic scenarios: the moderate RCP 4.5 and the extreme RCP 8.5. For the future, the two quantities are projected to be generally lower than in the past and the present, mainly due to the projected super-recovery of stratospheric ozone and reduced surface reflectivity. Although the greatest changes are projected over the Arctic Ocean and do not directly affect humans, the changes over land are also important. Over land, the greatest changes are found in northern Asia, Greenland and the north-east shores of Canada and Alaska. The greatest reductions over land are projected for April under all skies, locally reaching ∼30% for the noon UV index and ∼50% for the noon effective UV dose for the production of vitamin D.
Array Automated Assembly Task Low Cost Silicon Solar Array Project, Phase 2
NASA Technical Reports Server (NTRS)
Rhee, S. S.; Jones, G. T.; Allison, K. L.
1978-01-01
Progress in the development of solar cells and module process steps for low-cost solar arrays is reported. Specific topics covered include: (1) a system to automatically measure solar cell electrical performance parameters; (2) automation of wafer surface preparation, printing, and plating; (3) laser inspection of mechanical defects of solar cells; and (4) a silicon antireflection coating system. Two solar cell process steps, laser trimming and holing automation and spray-on dopant junction formation, are described.
1989-03-01
and June 15, a three person field team conducted the archaeological survey in the Cottonwood, Redwood, and Yellow Medicine subbasins. The project...discovering sites that are exposed on the ground surface. A three- person survey team can examine between 100 and 150 acres per day, depending on field...results are dependent on the interval used between individual shovel tests. When 15 meter intervals between tests are used, we estimate that one person
1994-01-01
second gate indicating that the intruder is a runner or a fast truck. FILTER ASCPNFIER ONESHOT AND LOGIC BUS B note: t 0 0 7 the Q--. BISTABLE MV...Minutes of the PINTSITIWG Meeting. Test Integration Working Group, Fort Belvoir Research . Development and Engineering Center, Ft. Belvoir. VA, 22 April...MP-CD ADVANCED RESEARCH PROJECT AGENCY ATTN: ATZN-MP-DE ATTN: EAO ATTN: ATZN-MP-TB ATTN: STO N DOHERTY ATTN: ATZN-MP-TS DEFENSE INTELLIGENCE AGENCY U
NASA Astrophysics Data System (ADS)
Liu, Ling
The primary goal of this research is the analysis, development, and experimental demonstration of an adaptive phase-locked fiber array system for free-space optical communications and laser beam projection applications. To our knowledge, the developed adaptive phase-locked system composed of three fiber collimators (subapertures) with tip-tilt wavefront phase control at each subaperture represents the first reported fiber array system that implements both phase-locking control and adaptive wavefront tip-tilt control capabilities. This research has also resulted in the following innovations: (a) The first experimental demonstration of a phase-locked fiber array with tip-tilt wave-front aberration compensation at each fiber collimator; (b) Development and demonstration of the fastest currently reported stochastic parallel gradient descent (SPGD) system capable of operation at 180,000 iterations per second; (c) The first experimental demonstration of a laser communication link based on a phase-locked fiber array; (d) The first successful experimental demonstration of turbulence and jitter-induced phase distortion compensation in a phase-locked fiber array optical system; (e) The first demonstration of laser beam projection onto an extended target with a randomly rough surface using a conformal adaptive fiber array system. Fiber array optical systems, the subject of this study, can overcome some of the draw-backs of conventional monolithic large-aperture transmitter/receiver optical systems that are usually heavy, bulky, and expensive. The primary experimental challenges in the development of the adaptive phased-locked fiber-array included precise (<5 microrad) alignment of the fiber collimators and development of fast (100kHz-class) phase-locking and wavefront tip-tilt control systems. The precise alignment of the fiber collimator array is achieved through a specially developed initial coarse alignment tool based on high precision piezoelectric picomotors and a dynamic fine alignment mechanism implemented with specially designed and manufactured piezoelectric fiber positioners. Phase-locking of the fiber collimators is performed by controlling the phases of the output beams (beamlets) using integrated polarization-maintaining (PM) fiber-coupled LiNbO3 phase shifters. The developed phase-locking controllers are based on either the SPGD algorithm or the multi-dithering technique. Subaperture wavefront phase tip-tilt control is realized using piezoelectric fiber positioners that are controlled using a computer-based SPGD controller. Both coherent (phase-locked) and incoherent beam combining in the fiber array system are analyzed theoretically and experimentally. Two special fiber-based beam-combining testbeds have been built to demonstrate the technical feasibility of phase-locking compensation prior to free-space operation. In addition, the reciprocity of counter-propagating beams in a phase-locked fiber array system has been investigated. Coherent beam combining in a phase-locking system with wavefront phase tip-tilt compensation at each subaperture is successfully demonstrated when laboratory-simulated turbulence and wavefront jitters are present in the propagation path of the beamlets. In addition, coherent beam combining with a non-cooperative extended target in the control loop is successfully demonstrated.
Moire measuring technology for three-dimensional profile of the object
NASA Astrophysics Data System (ADS)
Fu, Yanjun; Yang, Kuntao
2006-02-01
An optical system is designed to get projection of the transmission grating, the deformed grating is obtained on surface of the object. The image of the deformed grating is given by the lens, the reference grating is put on the place of the image, and then the moire fringe is obtained. The amplify principle of the moire fringe is used to measure the profile of the object. The optical principle of the projection is analyzed. And the relation between the phase and the height of object is deduced. From the different point of geometry optics and the physics opticsl, the optical system is analyzed, the factors that influence the image equality and the measuring result are obtained. So the betterment of improving the measuring precision is brought forward, and in the later information processing, because of the diffuse reflection, the image equality is not very well. In order to get a good image, the digital filter is used to filter the noise and smooth the image firstly. Then in order to improve the measure precision, the subdivision technology is applied. The Fourier transform profilometry and phase shifting technology is used in the calculation. A detail analyses is done both in time field and frequency field. And the method of improving the measuring precision is put forward. A good digital filter algorithm is brought forward in the Fourier transform profilometry. In the phase shifting technology, the detail formula of three-step and four-step is given. At last the phase that is relational with the high information of the object is get, but the phase is disconnected phase, after the unwrapping algorithm,the disconnected phase is changed to be the continuous phase. Taking use of the relation between the phase and height, the height is obtained. Then the three-dimensional profile of the measured object can be reconstructed. The system is very convenient for non-contact measure of profile of some objects.
NASA Astrophysics Data System (ADS)
Breeson, Andrew C.; Sankar, Gopinathan; Goh, Gregory K. L.; Palgrave, Robert G.
2017-11-01
A method of quantitative phase analysis using valence band X-ray photoelectron spectra is presented and applied to the analysis of TiO2 anatase-rutile mixtures. The valence band spectra of pure TiO2 polymorphs were measured, and these spectral shapes used to fit valence band spectra from mixed phase samples. Given the surface sensitive nature of the technique, this yields a surface phase fraction. Mixed phase samples were prepared from high and low surface area anatase and rutile powders. In the samples studied here, the surface phase fraction of anatase was found to be linearly correlated with photocatalytic activity of the mixed phase samples, even for samples with very different anatase and rutile surface areas. We apply this method to determine the surface phase fraction of P25 powder. This method may be applied to other systems where a surface phase fraction is an important characteristic.
Project M: Scale Model of Lunar Landing Site of Apollo 17: Focus on Lighting Conditions and Analysis
NASA Technical Reports Server (NTRS)
Vanik, Christopher S.; Crain, Timothy P.
2010-01-01
This document captures the research and development of a scale model representation of the Apollo 17 landing site on the moon as part of the NASA INSPIRE program. Several key elements in this model were surface slope characteristics, crater sizes and locations, prominent rocks, and lighting conditions. This model supports development of Autonomous Landing and Hazard Avoidance Technology (ALHAT) and Project M for the GN&C Autonomous Flight Systems Branch. It will help project engineers visualize the landing site, and is housed in the building 16 Navigation Systems Technology Lab. The lead mentor was Dr. Timothy P. Crain. The purpose of this project was to develop an accurate scale representation of the Apollo 17 landing site on the moon. This was done on an 8'2.5"X10'1.375" reduced friction granite table, which can be restored to its previous condition if needed. The first step in this project was to research the best way to model and recreate the Apollo 17 landing site for the mockup. The project required a thorough plan, budget, and schedule, which was presented to the EG6 Branch for build approval. The final phase was to build the model. The project also required thorough research on the Apollo 17 landing site and the topography of the moon. This research was done on the internet and in person with Dean Eppler, a space scientist, from JSC KX. This data was used to analyze and calculate the scale of the mockup and the ratio of the sizes of the craters, ridges, etc. The final goal was to effectively communicate project status and demonstrate the multiple advantages of using our model. The conclusion of this project was that the mockup was completed as accurately as possible, and it successfully enables the Project M specialists to visualize and plan their goal on an accurate three dimensional surface representation.
Surface wave phase velocities from 2-D surface wave tomography studies in the Anatolian plate
NASA Astrophysics Data System (ADS)
Arif Kutlu, Yusuf; Erduran, Murat; Çakır, Özcan; Vinnik, Lev; Kosarev, Grigoriy; Oreshin, Sergey
2014-05-01
We study the Rayleigh and Love surface wave fundamental mode propagation beneath the Anatolian plate. To examine the inter-station phase velocities a two-station method is used along with the Multiple Filter Technique (MFT) in the Computer Programs in Seismology (Herrmann and Ammon, 2004). The near-station waveform is deconvolved from the far-station waveform removing the propagation effects between the source and the station. This method requires that the near and far stations are aligned with the epicentre on a great circle path. The azimuthal difference of the earthquake to the two-stations and the azimuthal difference between the earthquake and the station are restricted to be smaller than 5o. We selected 3378 teleseismic events (Mw >= 5.7) recorded by 394 broadband local stations with high signal-to-noise ratio within the years 1999-2013. Corrected for the instrument response suitable seismogram pairs are analyzed with the two-station method yielding a collection of phase velocity curves in various period ranges (mainly in the range 25-185 sec). Diffraction from lateral heterogeneities, multipathing, interference of Rayleigh and Love waves can alter the dispersion measurements. In order to obtain quality measurements, we select only smooth portions of the phase velocity curves, remove outliers and average over many measurements. We discard these average phase velocity curves suspected of suffering from phase wrapping errors by comparing them with a reference Earth model (IASP91 by Kennett and Engdahl, 1991). The outlined analysis procedure yields 3035 Rayleigh and 1637 Love individual phase velocity curves. To obtain Rayleigh and Love wave travel times for a given region we performed 2-D tomographic inversion for which the Fast Marching Surface Tomography (FMST) code developed by N. Rawlinson at the Australian National University was utilized. This software package is based on the multistage fast marching method by Rawlinson and Sambridge (2004a, 2004b). The azimuthal coverage of the respective two-station paths is proper to analyze the observed dispersion curves in terms of both azimuthal and radial anisotropy beneath the study region. This research is supported by Joint Research Project of the Scientific and Research Council of Turkey (TUBİTAK- Grant number 111Y190) and the Russian Federation for Basic Research (RFBR).
NASA Technical Reports Server (NTRS)
Francoeur, J. R.
1992-01-01
The Strategic Technologies in Automation and Robotics (STEAR) program is managing a number of development contracts to improve the protection of spacecraft materials from the Low Earth Orbit (LEO) space environment. The project is structured in two phases over a 3 to 4 year period with a budget of 3 to 4 million dollars. Phase 1 is designed to demonstrate the technical feasibility and commercial potential of a coating/substrate system and its associated application process. The objective is to demonstrate a prototype fabrication capability using a full scale component of a commercially viable process for the protection of materials and surface finishes from the LEO space environment, and to demonstrate compliance with a set of performance requirements. Only phase 1 will be discussed in this paper.
Short-term climate change impacts on Mara basin hydrology
NASA Astrophysics Data System (ADS)
Demaria, E. M.; Roy, T.; Valdés, J. B.; Lyon, B.; Valdés-Pineda, R.; Serrat-Capdevila, A.; Durcik, M.; Gupta, H.
2017-12-01
The predictability of climate diminishes significantly at shorter time scales (e.g. decadal). Both natural variability as well as sampling variability of climate can obscure or enhance climate change signals in these shorter scales. Therefore, in order to assess the impacts of climate change on basin hydrology, it is important to design climate projections with exhaustive climate scenarios. In this study, we first create seasonal climate scenarios by combining (1) synthetic precipitation projections generated from a Vector Auto-Regressive (VAR) model using the University of East Anglia Climate Research Unit (UEA-CRU) data with (2) seasonal trends calculated from 31 models in the Coupled Model Intercomparison Project Phase 5 (CMIP). The seasonal climate projections are then disaggregated to daily level using the Agricultural Modern-Era Retrospective Analysis for Research and Applications (AgMERRA) data. The daily climate data are then bias-corrected and used as forcings to the land-surface model, Variable Infiltration Capacity (VIC), to generate different hydrological projections for the Mara River basin in East Africa, which are then evaluated to study the hydrologic changes in the basin in the next three decades (2020-2050).
A projection method for coupling two-phase VOF and fluid structure interaction simulations
NASA Astrophysics Data System (ADS)
Cerroni, Daniele; Da Vià, Roberto; Manservisi, Sandro
2018-02-01
The study of Multiphase Fluid Structure Interaction (MFSI) is becoming of great interest in many engineering applications. In this work we propose a new algorithm for coupling a FSI problem to a multiphase interface advection problem. An unstructured computational grid and a Cartesian mesh are used for the FSI and the VOF problem, respectively. The coupling between these two different grids is obtained by interpolating the velocity field into the Cartesian grid through a projection operator that can take into account the natural movement of the FSI domain. The piecewise color function is interpolated back on the unstructured grid with a Galerkin interpolation to obtain a point-wise function which allows the direct computation of the surface tension forces.
Entry Vehicle Control System Design for the Mars Smart Lander
NASA Technical Reports Server (NTRS)
Calhoun, Philip C.; Queen, Eric M.
2002-01-01
The NASA Langley Research Center, in cooperation with the Jet Propulsion Laboratory, participated in a preliminary design study of the Entry, Descent and Landing phase for the Mars Smart Lander Project. This concept utilizes advances in Guidance, Navigation and Control technology to significantly reduce uncertainty in the vehicle landed location on the Mars surface. A candidate entry vehicle controller based on the Reaction Control System controller for the Apollo Lunar Excursion Module digital autopilot is proposed for use in the entry vehicle attitude control. A slight modification to the phase plane controller is used to reduce jet-firing chattering while maintaining good control response for the Martian entry probe application. The controller performance is demonstrated in a six-degree-of-freedom simulation with representative aerodynamics.
Ultrafast electron transport across nano gaps in nanowire circuits
DOE Office of Scientific and Technical Information (OSTI.GOV)
Potma, Eric O.
In this Program we aim for a closer look at electron transfer through single molecules. To achieve this, we use ultrafast laser pulses to time stamp an electron tunneling event in a molecule that is connected between two metallic electrodes, while reading out the electron current. A key aspect of this project is the use of metallic substrates with plasmonic activity to efficiently manipulate the tunneling probability. The first Phase of this program is concerned with developing highly sensitive tools for the ultrafast optical manipulation of tethered molecules through the evanescent surface field of plasmonic substrates. The second Phase ofmore » the program aims to use these tools for exercising control over the electron tunneling probability.« less
Project NOAH: Regulating modern sea-level rise. Phase II: Jerusalem Underground
NASA Astrophysics Data System (ADS)
Newman, Walter S.; Fairbridge, Rhodes W.
This proposal builds a high-speed inter-urban express between Jerusalem and Tel Aviv, generates 1500 megawatts of hydroelectric energy, curtails littoral erosion, builds a port along the Israeli Mediterranean coast and demands peaceful cooperation on both sides of the Jordan River. Phase II represents a pilot project demonstrating the feasibility of continuing to regulate world sea-level by a new series of water regulation schemes. Phase I previously described all those projects already completed or underway which have inadvertently and/or unintentionally served the purpose of sea-level regulation. These forms of Phase I sea-level regulation include large and small reservoirs, irrigation projects, water infiltration schemes, farm ponds, and swimming and reflecting pools. All these water storage projects have already exercised a very appreciable brake on 20th century sea-level rise. Phase II outlines a high-visibility proposal which will serve to illustrate the viability of “Project NOAH”.
ERIC Educational Resources Information Center
Mauro, Nicole; Buck-Bernard, Jennifer
1998-01-01
Describes a yearlong project that involves biology students in monitoring water quality. Includes details of the awareness phase, action phase, and presentation phase. Discusses student reaction to the project. (DDR)
Heo, Tae Wook; Chen, Long-Qing; Wood, Brandon C.
2015-04-08
In this paper, we present a comprehensive phase-field model for simulating diffusion-mediated kinetic phase behaviors near the surface of a solid particle. The model incorporates elastic inhomogeneity and anisotropy, diffusion mobility anisotropy, interfacial energy anisotropy, and Cahn–Hilliard diffusion kinetics. The free energy density function is formulated based on the regular solution model taking into account the possible solute-surface interaction near the surface. The coherency strain energy is computed using the Fourier-spectral iterative-perturbation method due to the strong elastic inhomogeneity with a zero surface traction boundary condition. Employing a phase-separating Li XFePO 4 electrode particle for Li-ion batteries as a modelmore » system, we perform parametric three-dimensional computer simulations. The model permits the observation of surface phase behaviors that are different from the bulk counterpart. For instance, it reproduces the theoretically well-established surface modes of spinodal decomposition of an unstable solid solution: the surface mode of coherent spinodal decomposition and the surface-directed spinodal decomposition mode. We systematically investigate the influences of major factors on the kinetic surface phase behaviors during the diffusional process. Finally, our simulation study provides insights for tailoring the internal phase microstructure of a particle by controlling the surface phase morphology.« less
23 CFR 630.106 - Authorization to proceed.
Code of Federal Regulations, 2011 CFR
2011-04-01
... estimate when the bid is approved, a project phase is completed, a design change is approved, etc...) phase(s) through the selection of a location. (3) Projects for ROW acquisition in hardship and... reflect any substantive change in the bids received as compared to the STD's estimated cost of the project...
23 CFR 630.106 - Authorization to proceed.
Code of Federal Regulations, 2012 CFR
2012-04-01
... estimate when the bid is approved, a project phase is completed, a design change is approved, etc...) phase(s) through the selection of a location. (3) Projects for ROW acquisition in hardship and... reflect any substantive change in the bids received as compared to the STD's estimated cost of the project...
23 CFR 630.106 - Authorization to proceed.
Code of Federal Regulations, 2010 CFR
2010-04-01
... estimate when the bid is approved, a project phase is completed, a design change is approved, etc...) phase(s) through the selection of a location. (3) Projects for ROW acquisition in hardship and... reflect any substantive change in the bids received as compared to the STD's estimated cost of the project...
The western Pacific monsoon in CMIP5 models: Model evaluation and projections
NASA Astrophysics Data System (ADS)
Brown, Josephine R.; Colman, Robert A.; Moise, Aurel F.; Smith, Ian N.
2013-11-01
ability of 35 models from the Coupled Model Intercomparison Project Phase 5 (CMIP5) to simulate the western Pacific (WP) monsoon is evaluated over four representative regions around Timor, New Guinea, the Solomon Islands and Palau. Coupled model simulations are compared with atmosphere-only model simulations (with observed sea surface temperatures, SSTs) to determine the impact of SST biases on model performance. Overall, the CMIP5 models simulate the WP monsoon better than previous-generation Coupled Model Intercomparison Project Phase 3 (CMIP3) models, but some systematic biases remain. The atmosphere-only models are better able to simulate the seasonal cycle of zonal winds than the coupled models, but display comparable biases in the rainfall. The CMIP5 models are able to capture features of interannual variability in response to the El Niño-Southern Oscillation. In climate projections under the RCP8.5 scenario, monsoon rainfall is increased over most of the WP monsoon domain, while wind changes are small. Widespread rainfall increases at low latitudes in the summer hemisphere appear robust as a large majority of models agree on the sign of the change. There is less agreement on rainfall changes in winter. Interannual variability of monsoon wet season rainfall is increased in a warmer climate, particularly over Palau, Timor and the Solomon Islands. A subset of the models showing greatest skill in the current climate confirms the overall projections, although showing markedly smaller rainfall increases in the western equatorial Pacific. The changes found here may have large impacts on Pacific island countries influenced by the WP monsoon.
The Southern Ocean as a constraint to reduce uncertainty in future ocean carbon sinks
Kessler, A.; Tjiputra, J.
2016-04-07
Earth system model (ESM) simulations exhibit large biases compares to observation-based estimates of the present ocean CO 2 sink. The inter-model spread in projections increases nearly 2-fold by the end of the 21st century and therefore contributes significantly to the uncertainty of future climate projections. In this study, the Southern Ocean (SO) is shown to be one of the hot-spot regions for future uptake of anthropogenic CO 2, characterized by both the solubility pump and biologically mediated carbon drawdown in the spring and summer. Here, we show, by analyzing a suite of fully interactive ESMs simulations from the Coupled Model Intercomparisonmore » Project phase 5 (CMIP5) over the 21st century under the high-CO 2 Representative Concentration Pathway (RCP) 8.5 scenario, that the SO is the only region where the atmospheric CO 2 uptake rate continues to increase toward the end of the 21st century. Furthermore, our study discovers a strong inter-model link between the contemporary CO 2 uptake in the Southern Ocean and the projected global cumulated uptake over the 21st century. This strong correlation suggests that models with low (high) carbon uptake rate in the contemporary SO tend to simulate low (high) uptake rate in the future. None the less, our analysis also shows that none of the models fully capture the observed biophysical mechanisms governing the CO 2 fluxes in the SO. The inter-model spread for the contemporary CO 2 uptake in the Southern Ocean is attributed to the variations in the simulated seasonal cycle of surface pCO 2. Two groups of model behavior have been identified. The first one simulates anomalously strong SO carbon uptake, generally due to both too strong a net primary production and too low a surface pCO 2 in December–January. The second group simulates an opposite CO 2 flux seasonal phase, which is driven mainly by the bias in the sea surface temperature variability. Furthermore, we show that these biases are persistent throughout the 21st century, which highlights the urgent need for a sustained and comprehensive biogeochemical monitoring system in the Southern Ocean to better constrain key processes represented in current model systems.« less
The Southern Ocean as a constraint to reduce uncertainty in future ocean carbon sinks
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kessler, A.; Tjiputra, J.
Earth system model (ESM) simulations exhibit large biases compares to observation-based estimates of the present ocean CO 2 sink. The inter-model spread in projections increases nearly 2-fold by the end of the 21st century and therefore contributes significantly to the uncertainty of future climate projections. In this study, the Southern Ocean (SO) is shown to be one of the hot-spot regions for future uptake of anthropogenic CO 2, characterized by both the solubility pump and biologically mediated carbon drawdown in the spring and summer. Here, we show, by analyzing a suite of fully interactive ESMs simulations from the Coupled Model Intercomparisonmore » Project phase 5 (CMIP5) over the 21st century under the high-CO 2 Representative Concentration Pathway (RCP) 8.5 scenario, that the SO is the only region where the atmospheric CO 2 uptake rate continues to increase toward the end of the 21st century. Furthermore, our study discovers a strong inter-model link between the contemporary CO 2 uptake in the Southern Ocean and the projected global cumulated uptake over the 21st century. This strong correlation suggests that models with low (high) carbon uptake rate in the contemporary SO tend to simulate low (high) uptake rate in the future. None the less, our analysis also shows that none of the models fully capture the observed biophysical mechanisms governing the CO 2 fluxes in the SO. The inter-model spread for the contemporary CO 2 uptake in the Southern Ocean is attributed to the variations in the simulated seasonal cycle of surface pCO 2. Two groups of model behavior have been identified. The first one simulates anomalously strong SO carbon uptake, generally due to both too strong a net primary production and too low a surface pCO 2 in December–January. The second group simulates an opposite CO 2 flux seasonal phase, which is driven mainly by the bias in the sea surface temperature variability. Furthermore, we show that these biases are persistent throughout the 21st century, which highlights the urgent need for a sustained and comprehensive biogeochemical monitoring system in the Southern Ocean to better constrain key processes represented in current model systems.« less
Electronic structure and surface properties of MgB2(0001) upon oxygen adsorption
NASA Astrophysics Data System (ADS)
Kim, Chang-Eun; Ray, Keith G.; Bahr, David F.; Lordi, Vincenzo
2018-05-01
We use density-functional theory to investigate the bulk and surface properties of MgB2. The unique bonding structure of MgB2 is investigated by Bader's atoms-in-molecules, charge density difference, and occupancy projected band structure analyses. Oxygen adsorption on the charge-depleted surfaces of MgB2 is studied by a surface potential energy mapping method, reporting a complete map including low-symmetry binding sites. The B-terminated MgB2(0001) demonstrates reconstruction of the graphenelike B layer, and the reconstructed geometry exposes a threefold site of the subsurface Mg, making it accessible from the surface. Detailed reconstruction mechanisms are studied by simulated annealing method based on ab initio molecular dynamics and nudged elastic band calculations. The surface clustering of B atoms significantly modifies the B 2 p states to occupy low energy valence states. The present paper emphasizes that a thorough understanding of the surface phase may explain an apparent inconsistency in the experimental surface characterization of MgB2. Furthermore, these results suggest that the surface passivation can be an important technical challenge when it comes to development of a superconducting device using MgB2.
Speckle phase near random surfaces
NASA Astrophysics Data System (ADS)
Chen, Xiaoyi; Cheng, Chuanfu; An, Guoqiang; Han, Yujing; Rong, Zhenyu; Zhang, Li; Zhang, Meina
2018-03-01
Based on Kirchhoff approximation theory, the speckle phase near random surfaces with different roughness is numerically simulated. As expected, the properties of the speckle phase near the random surfaces are different from that in far field. In addition, as scattering distances and roughness increase, the average fluctuations of the speckle phase become larger. Unusually, the speckle phase is somewhat similar to the corresponding surface topography. We have performed experiments to verify the theoretical simulation results. Studies in this paper contribute to understanding the evolution of speckle phase near a random surface and provide a possible way to identify a random surface structure based on its speckle phase.
Detection and localization capability of an urban seismic sinkhole monitoring network
NASA Astrophysics Data System (ADS)
Becker, Dirk; Dahm, Torsten; Schneider, Fabian
2017-04-01
Microseismic events linked to underground processes in sinkhole areas might serve as precursors to larger mass dislocation or rupture events which can cause felt ground shaking or even structural damage. To identify these weak and shallow events, a sensitive local seismic monitoring network is needed. In case of an urban environment the performance of local monitoring networks is severely compromised by the high anthropogenic noise level. We study the detection and localization capability of such a network, which is already partly installed in the urban area of the city of Hamburg, Germany, within the joint project SIMULTAN (http://www.gfz-potsdam.de/en/section/near-surface-geophysics/projects/simultan/). SIMULTAN aims to monitor a known sinkhole structure and gain a better understanding of the underlying processes. The current network consists of six surface stations installed in the basement of private houses and underground structures of a research facility (DESY - Deutsches Elektronen Synchrotron). During the started monitoring campaign since 2015, no microseismic events could be unambiguously attributed to the sinkholes. To estimate the detection and location capability of the network, we calculate synthetic waveforms based on the location and mechanism of former events in the area. These waveforms are combined with the recorded urban seismic noise at the station sites. As detection algorithms a simple STA/LTA trigger and a more sophisticated phase detector are used. While the STA/LTA detector delivers stable results and is able to detect events with a moment magnitude as low as 0.35 at a distance of 1.3km from the source even under the present high noise conditions the phase detector is more sensitive but also less stable. It should be stressed that due to the local near surface conditions of the wave propagation the detections are generally performed on S- or surface waves and not on P-waves, which have a significantly lower amplitude. Due to the often emergent onsets of the seismic phases of sinkhole events and the high noise conditions the localization capability of the network is assessed by a stacking approach of characteristic waveforms (STA/LTA traces) in addition to traditional estimates based on travel time uncertainties and network geometry. Also the effect of a vertical array of borehole sensors as well as a small scale surface array on the location accuracy is investigated. Due to the expected, rather low frequency character of the seismic signals arrays with a small aperture due to the required close proximity to the source exhibit considerable uncertainty in the determination of the azimuth of the incoming wavefront, but can contribute to better constrain the event location. Future borehole stations, apart from significantly reducing the detection threshold, would also significantly reduce the location uncertainty. In addition, the synthetic data sets created for this study can also be used to better constrain the magnitudes of the microseismic events by deriving attenuation relations for the surface waves of shallow events encountered in the sinkhole environment. This work has been funded by the German 'Geotechnologien' project SIMULTAN (BMBF03G0737A).
Fission Surface Power System Initial Concept Definition
NASA Technical Reports Server (NTRS)
2010-01-01
Under the NASA Exploration Technology Development Program (ETDP) and in partnership with the Department of Energy (DOE), NASA has embarked on a project to develop Fission Surface Power (FSP) technology. The primary goals of the project are to 1) develop FSP concepts that meet expected surface power requirements at reasonable cost with added benefits over other options, 2) establish a hardwarebased technical foundation for FSP design concepts and reduce overall development risk, 3) reduce the cost uncertainties for FSP and establish greater credibility for flight system cost estimates, and 4) generate the key products to allow NASA decision-makers to consider FSP as a preferred option for flight development. The FSP project was initiated in 2006 as the Prometheus Program and the Jupiter Icy Moons Orbiter (JIMO) mission were phased-out. As a first step, NASA Headquarters commissioned the Affordable Fission Surface Power System Study to evaluate the potential for an affordable FSP development approach. With a cost-effective FSP strategy identified, the FSP team evaluated design options and selected a Preliminary Reference Concept to guide technology development. Since then, the FSP Preliminary Reference Concept has served as a point-of-departure for several NASA mission architecture studies examining the use of nuclear power and has provided the foundation for a series of "Pathfinder" hardware tests. The long-term technology goal is a Technology Demonstration Unit (TDU) integrated system test using full-scale components and a non-nuclear reactor simulator. The FSP team consists of Glenn Research Center (GRC), Marshall Space Flight Center (MSFC) and the DOE National Laboratories at Los Alamos (LANL), Idaho (INL), Oak Ridge (ORNL), and Sandia (SNL). The project is organized into two main elements: Concept Definition and Risk Reduction. Under Concept Definition, the team performs trade studies, develops analytical tools, and formulates system concepts. Under Risk Reduction the team develops hardware prototypes and conducts laboratory-based testing.
ERIC Educational Resources Information Center
Nerenz, Anne G.; Webb, Norman L.
This is one of a series of reports which provide definitions of and descriptive data on the variables used in the Comparative Study of Phase IV of the Individually Guided Education (IEG) Evaluation Project. Phase IV investigated three curriculum programs specifically designed to be compatible with instructional programming for the individual…
20-mN Variable Specific Impulse (Isp) Colloid Thruster
NASA Technical Reports Server (NTRS)
Demmons, Nathaniel
2015-01-01
Busek Company, Inc., has designed and manufactured an electrospray emitter capable of generating 20 mN in a compact package (7x7x1.7 in). The thruster consists of nine porous-surface emitters operating in parallel from a common propellant supply. Each emitter is capable of supporting over 70,000 electrospray emission sites with the plume from each emitter being accelerated through a single aperture, eliminating the need for individual emission site alignment to an extraction grid. The total number of emission sites during operation is expected to approach 700,000. This Phase II project optimized and characterized the thruster fabricated during the Phase I effort. Additional porous emitters also were fabricated for full-scale testing. Propellant is supplied to the thruster via existing feed-system and microvalve technology previously developed by Busek, under the NASA Space Technology 7's Disturbance Reduction System (ST7-DRS) mission and via follow-on electric propulsion programs. This project investigated methods for extending thruster life beyond the previously demonstrated 450 hours. The life-extending capabilities will be demonstrated on a subscale version of the thruster.
Status of NASA's Advanced Radioisotope Power Conversion Technology Research and Development
NASA Technical Reports Server (NTRS)
Wong, Wayne A.; Anderson, David J.; Tuttle, Karen L.; Tew, Roy C.
2006-01-01
NASA s Advanced Radioisotope Power Systems (RPS) development program is funding the advancement of next generation power conversion technologies that will enable future missions that have requirements that can not be met by either the ubiquitous photovoltaic systems or by current Radioisotope Power Systems (RPS). Requirements of advanced radioisotope power systems include high efficiency and high specific power (watts/kilogram) in order to meet mission requirements with less radioisotope fuel and lower mass. Other Advanced RPS development goals include long-life, reliability, and scalability so that these systems can meet requirements for a variety of future space applications including continual operation surface missions, outer-planetary missions, and solar probe. This paper provides an update on the Radioisotope Power Conversion Technology Project which awarded ten Phase I contracts for research and development of a variety of power conversion technologies consisting of Brayton, Stirling, thermoelectrics, and thermophotovoltaics. Three of the contracts continue during the current Phase II in the areas of thermoelectric and Stirling power conversion. The accomplishments to date of the contractors, project plans, and status will be summarized.
An Overview of Air-Breathing Propulsion Efforts for 2015 SBIR Phase I
NASA Technical Reports Server (NTRS)
Nguyen, Hung D.; Steele, Gynelle C.
2016-01-01
NASA's Small Business Innovation Research (SBIR) program focuses on technological innovation by investing in development of innovative concepts and technologies to help NASA mission directorates address critical research needs for Agency programs. This report highlights 24 of the innovative SBIR 2015 Phase I projects that emphasize one of NASA Glenn Research Center's six core competencies-Air-Breathing Propulsion. The technologies cover a wide spectrum of applications such as hybrid nanocomposites for efficient aerospace structures; plasma flow control for drag reduction; physics-based aeroanalysis methods for open rotor conceptual designs; vertical lift by series hybrid power; fast pressure-sensitive paint systems for production wind tunnel testing; rugged, compact, and inexpensive airborne fiber sensor interrogators based on monolithic tunable lasers; and high sensitivity semiconductor sensor skins for multi-axis surface pressure characterization. Each featured technology describes an innovation and technical objective and highlights NASA commercial and industrial applications. This report provides an opportunity for NASA engineers, researchers, and program managers to learn how NASA SBIR technologies could help their programs and projects, and lead to collaborations and partnerships between the small SBIR companies and NASA that would benefit both.
Embedded 3D shape measurement system based on a novel spatio-temporal coding method
NASA Astrophysics Data System (ADS)
Xu, Bin; Tian, Jindong; Tian, Yong; Li, Dong
2016-11-01
Structured light measurement has been wildly used since 1970s in industrial component detection, reverse engineering, 3D molding, robot navigation, medical and many other fields. In order to satisfy the demand for high speed, high precision and high resolution 3-D measurement for embedded system, a new patterns combining binary and gray coding principle in space are designed and projected onto the object surface orderly. Each pixel corresponds to the designed sequence of gray values in time - domain, which is treated as a feature vector. The unique gray vector is then dimensionally reduced to a scalar which could be used as characteristic information for binocular matching. In this method, the number of projected structured light patterns is reduced, and the time-consuming phase unwrapping in traditional phase shift methods is avoided. This algorithm is eventually implemented on DM3730 embedded system for 3-D measuring, which consists of an ARM and a DSP core and has a strong capability of digital signal processing. Experimental results demonstrated the feasibility of the proposed method.
NASA Astrophysics Data System (ADS)
Saye, Robert
2017-09-01
In this two-part paper, a high-order accurate implicit mesh discontinuous Galerkin (dG) framework is developed for fluid interface dynamics, facilitating precise computation of interfacial fluid flow in evolving geometries. The framework uses implicitly defined meshes-wherein a reference quadtree or octree grid is combined with an implicit representation of evolving interfaces and moving domain boundaries-and allows physically prescribed interfacial jump conditions to be imposed or captured with high-order accuracy. Part one discusses the design of the framework, including: (i) high-order quadrature for implicitly defined elements and faces; (ii) high-order accurate discretisation of scalar and vector-valued elliptic partial differential equations with interfacial jumps in ellipticity coefficient, leading to optimal-order accuracy in the maximum norm and discrete linear systems that are symmetric positive (semi)definite; (iii) the design of incompressible fluid flow projection operators, which except for the influence of small penalty parameters, are discretely idempotent; and (iv) the design of geometric multigrid methods for elliptic interface problems on implicitly defined meshes and their use as preconditioners for the conjugate gradient method. Also discussed is a variety of aspects relating to moving interfaces, including: (v) dG discretisations of the level set method on implicitly defined meshes; (vi) transferring state between evolving implicit meshes; (vii) preserving mesh topology to accurately compute temporal derivatives; (viii) high-order accurate reinitialisation of level set functions; and (ix) the integration of adaptive mesh refinement. In part two, several applications of the implicit mesh dG framework in two and three dimensions are presented, including examples of single phase flow in nontrivial geometry, surface tension-driven two phase flow with phase-dependent fluid density and viscosity, rigid body fluid-structure interaction, and free surface flow. A class of techniques known as interfacial gauge methods is adopted to solve the corresponding incompressible Navier-Stokes equations, which, compared to archetypical projection methods, have a weaker coupling between fluid velocity, pressure, and interface position, and allow high-order accurate numerical methods to be developed more easily. Convergence analyses conducted throughout the work demonstrate high-order accuracy in the maximum norm for all of the applications considered; for example, fourth-order spatial accuracy in fluid velocity, pressure, and interface location is demonstrated for surface tension-driven two phase flow in 2D and 3D. Specific application examples include: vortex shedding in nontrivial geometry, capillary wave dynamics revealing fine-scale flow features, falling rigid bodies tumbling in unsteady flow, and free surface flow over a submersed obstacle, as well as high Reynolds number soap bubble oscillation dynamics and vortex shedding induced by a type of Plateau-Rayleigh instability in water ripple free surface flow. These last two examples compare numerical results with experimental data and serve as an additional means of validation; they also reveal physical phenomena not visible in the experiments, highlight how small-scale interfacial features develop and affect macroscopic dynamics, and demonstrate the wide range of spatial scales often at play in interfacial fluid flow.
NASA Astrophysics Data System (ADS)
Saye, Robert
2017-09-01
In this two-part paper, a high-order accurate implicit mesh discontinuous Galerkin (dG) framework is developed for fluid interface dynamics, facilitating precise computation of interfacial fluid flow in evolving geometries. The framework uses implicitly defined meshes-wherein a reference quadtree or octree grid is combined with an implicit representation of evolving interfaces and moving domain boundaries-and allows physically prescribed interfacial jump conditions to be imposed or captured with high-order accuracy. Part one discusses the design of the framework, including: (i) high-order quadrature for implicitly defined elements and faces; (ii) high-order accurate discretisation of scalar and vector-valued elliptic partial differential equations with interfacial jumps in ellipticity coefficient, leading to optimal-order accuracy in the maximum norm and discrete linear systems that are symmetric positive (semi)definite; (iii) the design of incompressible fluid flow projection operators, which except for the influence of small penalty parameters, are discretely idempotent; and (iv) the design of geometric multigrid methods for elliptic interface problems on implicitly defined meshes and their use as preconditioners for the conjugate gradient method. Also discussed is a variety of aspects relating to moving interfaces, including: (v) dG discretisations of the level set method on implicitly defined meshes; (vi) transferring state between evolving implicit meshes; (vii) preserving mesh topology to accurately compute temporal derivatives; (viii) high-order accurate reinitialisation of level set functions; and (ix) the integration of adaptive mesh refinement. In part two, several applications of the implicit mesh dG framework in two and three dimensions are presented, including examples of single phase flow in nontrivial geometry, surface tension-driven two phase flow with phase-dependent fluid density and viscosity, rigid body fluid-structure interaction, and free surface flow. A class of techniques known as interfacial gauge methods is adopted to solve the corresponding incompressible Navier-Stokes equations, which, compared to archetypical projection methods, have a weaker coupling between fluid velocity, pressure, and interface position, and allow high-order accurate numerical methods to be developed more easily. Convergence analyses conducted throughout the work demonstrate high-order accuracy in the maximum norm for all of the applications considered; for example, fourth-order spatial accuracy in fluid velocity, pressure, and interface location is demonstrated for surface tension-driven two phase flow in 2D and 3D. Specific application examples include: vortex shedding in nontrivial geometry, capillary wave dynamics revealing fine-scale flow features, falling rigid bodies tumbling in unsteady flow, and free surface flow over a submersed obstacle, as well as high Reynolds number soap bubble oscillation dynamics and vortex shedding induced by a type of Plateau-Rayleigh instability in water ripple free surface flow. These last two examples compare numerical results with experimental data and serve as an additional means of validation; they also reveal physical phenomena not visible in the experiments, highlight how small-scale interfacial features develop and affect macroscopic dynamics, and demonstrate the wide range of spatial scales often at play in interfacial fluid flow.
Sentinel-2A image quality commissioning phase final results: geometric calibration and performances
NASA Astrophysics Data System (ADS)
Languille, F.; Gaudel, A.; Dechoz, C.; Greslou, D.; de Lussy, F.; Trémas, T.; Poulain, V.; Massera, S.
2016-10-01
In the frame of the Copernicus program of the European Commission, Sentinel-2 offers multispectral high-spatial-resolution optical images over global terrestrial surfaces. In cooperation with ESA, the Centre National d'Etudes Spatiales (CNES) is in charge of the image quality of the project, and so ensures the CAL/VAL commissioning phase during the months following the launch. Sentinel-2 is a constellation of 2 satellites on a polar sun-synchronous orbit with a revisit time of 5 days (with both satellites), a high field of view - 290km, 13 spectral bands in visible and shortwave infrared, and high spatial resolution - 10m, 20m and 60m. The Sentinel-2 mission offers a global coverage over terrestrial surfaces. The satellites acquire systematically terrestrial surfaces under the same viewing conditions in order to have temporal images stacks. The first satellite was launched in June 2015. Following the launch, the CAL/VAL commissioning phase is then lasting during 6 months for geometrical calibration. This paper will point on observations and results seen on Sentinel-2 images during commissioning phase. It will provide explanations about Sentinel-2 products delivered with geometric corrections. This paper will detail calibration sites, and the methods used for geometrical parameters calibration and will present linked results. The following topics will be presented: viewing frames orientation assessment, focal plane mapping for all spectral bands, results on geolocation assessment, and multispectral registration. There is a systematic images recalibration over a same reference which is a set of S2 images produced during the 6 months of CAL/VAL. This set of images will be presented as well as the geolocation performance and the multitemporal performance after refining over this ground reference.
A Simulated Chlorine-Saturated Lunar Magmatic System at the Surface and At Depth
NASA Astrophysics Data System (ADS)
DiFrancesco, N.; Nekvasil, H.; Lindsley, D. H.
2016-12-01
Analysis of igneous minerals present in lunar rocks has provided evidence that volatiles such as water, chlorine and fluorine were concentrated in melts present at or near the lunar surface. While at depth, pressure on a magma allows these gases to remain dissolved in a silicate liquid, however as the magma ascends and depressurizes, these components become saturated and begin exsolving. While at pressure, it's possible for these components, specifically Cl, to form complexes in the melt with major cations such as Na, K, and Fe as well as trace elements such as Zn and Li. While dissolved in the melt, it may be possible for the Cl to inhibit the ability for these cations to enter into crystalline phases such as olivine, plagioclase, or pyroxene, potentially altering the composition of minerals associated with the melt. As the magma rises, these compounds are able to boil off from the magma, changing its bulk composition by effectively removing these cations as halides in a vapor phase. The goals of this project are to experimentally ascertain the nature of minerals sublimated by this degassing, and the effects that this process may have on the evolution and liquid line of decent for a cooling lunar magma. This is accomplished by crystallizing volatile-rich synthetic lunar basalts both at high and zero pressure and analyzing both vapor deposits and solidified liquids. Experimental data simulating volatile-rich magma degassing and crystallization at the lunar surface, and within the lunar crust has demonstrated that typical KREEP basalts (potentially rich in Cl) will crystallize more magnesian and calcic phases at high pressure, and subsequently lose alkalis and iron to a vapor phase at low pressure. We see evidence of vapor deposits and volatile element enrichment in returned Apollo samples such as "Rusty Rock", and on the surface of orange glass beads.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dodds, K.; Daley, T.; Freifeld, B.
2009-05-01
The Australian Cooperative Research Centre for Greenhouse Gas Technologies (CO2CRC) is currently injecting 100,000 tons of CO{sub 2} in a large-scale test of storage technology in a pilot project in southeastern Australia called the CO2CRC Otway Project. The Otway Basin, with its natural CO{sub 2} accumulations and many depleted gas fields, offers an appropriate site for such a pilot project. An 80% CO{sub 2} stream is produced from a well (Buttress) near the depleted gas reservoir (Naylor) used for storage (Figure 1). The goal of this project is to demonstrate that CO{sub 2} can be safely transported, stored underground, andmore » its behavior tracked and monitored. The monitoring and verification framework has been developed to monitor for the presence and behavior of CO{sub 2} in the subsurface reservoir, near surface, and atmosphere. This monitoring framework addresses areas, identified by a rigorous risk assessment, to verify conformance to clearly identifiable performance criteria. These criteria have been agreed with the regulatory authorities to manage the project through all phases addressing responsibilities, liabilities, and to assure the public of safe storage.« less
Mechanism of Corrosion by Naphthenic Acids and Organosulfur Compounds at High Temperatures
NASA Astrophysics Data System (ADS)
Jin, Peng
Due to the law of supply and demand, the last decade has witnessed a skyrocketing in the price of light sweet crude oil. Therefore, refineries are increasingly interested in "opportunity crudes", characterized by their discounted price and relative ease of procurement. However, the attractive economics of opportunity crudes come with the disadvantage of high acid/organosulfur compound content, which could lead to corrosion and even failure of facilities in refineries. However, it is generally accepted that organosulfur compounds may form protective iron sulfide layers on the metal surface and decrease the corrosion rate. Therefore, it is necessary to investigate the corrosive property of crudes at high temperatures, the mechanism of corrosion by acids (naphthenic acids) in the presence of organosulfur compounds, and methods to mitigate its corrosive effect. In 2004, an industrial project was initiated at the Institute for Corrosion and Multiphase Technology to investigate the corrosion by naphthenic acids and organosulfur compounds. In this project, for each experiment there were two experimentation phases: pretreatment and challenge. In the first pretreatment phase, a stirred autoclave was filled with a real crude oil fraction or model oil of different acidity and organosulfur compound concentration. Then, the stirred autoclave was heated to high temperatures to examine the corrosivity of the oil to different materials (specimens made from CS and 5% Cr containing steel were used). During the pretreatment, corrosion product layers were formed on the metal surface. In the second challenge phase, the steel specimens pretreated in the first phase were inserted into a rotating cylinder autoclave, called High Velocity Rig (HVR). The HVR was fed with a high-temperature oil solution of naphthenic acids to attack the iron sulfide layers. Based on the difference of specimen weight loss between the two steps, the net corrosion rate could be calculated and the protectiveness of corrosion product layer against naphthenic acid corrosion could be assessed. Routinely, the layers generated in pretreatment and challenge phases were investigated with SEM/EDS (Scanning Electron Microscopy/Energy Dispersive Spectroscopy). Selectively, some thin layers formed in the first or second phase were analyzed with FIB-TEM (Focused Ion Beam - Transmission Electron Microscopy). FIB-TEM analysis revealed that there was an iron oxide layer beneath the iron sulfide layer. Experimental results showed that the iron oxide layer was closely related to the layer protectiveness against naphthenic acid corrosion and its formation was due to the presence of naphthenic acids in the fluid. Finally, a new mechanism of naphthenic acid/organosulfur compound corrosion was proposed based on properties of crudes, results of corrosion experimentation, and microscopic analysis of developed surface layers.
The Atlanta Supersites project is the first of two Supersites projects to be established during Phase I of EPA's Supersites Program; Phase 11 is being established through a Request for Assistance. The other initial project is in Fresno, California. The Supersites Program is par...
Micropatterned photoalignment for wavefront controlled switchable optical devices
NASA Astrophysics Data System (ADS)
Glazar, Nikolaus
Photoalignment is a well-established technique for surface alignment of the liquid crystal director. Previously, chrome masks were necessary for patterned photoalignment but were difficult to use, costly, and inflexible. To extend the capabilities of photoalignment we built an automated maskless multi-domain photoalignment device based on a DMD (digital multimirror device) projection system. The device is capable of creating arbitrary photoalignment patterns with micron-sized features. Pancharatnam-Berry phase (PB-phase) is a geometric phase that arises from cyclic change of polarization state. By varying the azimuthal anchoring angle in a hybrid-aligned liquid crystal cell we can control the spatial variation of the PB-phase shift. Using our automated photoalignment device to align the liquid crystal arbitrary wave front manipulations are possible. The PB-phase shift effect is maximized when the cell is tuned to have a half-wave retardation and disappears at full-wave retardation, so the cell can be switched on and off by applying a voltage. Two wavefront controlled devices developed using this technique will be discussed: A switchable liquid crystal phase shift mask for creating sub-diffraction sized photolithographic features, and a transparent diffractive display that utilizes a switchable liquid crystal diffraction grating.
Optical transfer function in corneal topography for clinical contrast sensitivity analysis
NASA Astrophysics Data System (ADS)
Bende, Thomas; Jean, Benedikt J.; Oltrup, Theo
2000-06-01
Customized ablation aiming to optimize visual acuity in refractive surgery requires objective data on corneal surface, like the contrast sensitivity. Fast ray tracing, using the high resolution 3-D elevation data in conjunction with Snell's law describe the diffraction of the incident rays and the resulting image on a 'virtual retina.' A retroprojection leads to a 'surface quality map.' For objective contrast sensitivity measurement a sinus (or cos) wave of different frequencies is used for a calculated projection in analogy to the clinical contrast sensitivity charts. The projection on the individual cornea surface is analyzed for the Modular Transfer Function (MTF) and the Phase Shift Function (PSF) as a function of frequencies. PSF, not yet clinically used, is a parameter to determine even minimal corneal tilt. The resulting corneal aberration map (CAM) as described here and applied to a 4.5 D PRK (OZD equals 6.5 mm) reveals that the area of minimal aberration measures only 4.2 mm. The CAM can likewise be used to describe the 'quality' of a laser system's ablation pattern based upon the area of minimal optical aberrations. The CAM only describes surface aberration with high resolution, an advantage over wave front sensing which measures all accumulated optical aberrations including the changing ones of the lens during accommodation and the transient ones due to lens aging and early cataract formation.
Avionics Technology Contract Project Report Phase I with Research Findings.
ERIC Educational Resources Information Center
Sappe', Hoyt; Squires, Shiela S.
This document reports on Phase I of a project that examined the occupation of avionics technician, established appropriate committees, and conducted task verification. Results of this phase provide the basic information required to develop the program standards and to guide and set up the committee structure to guide the project. Section 1…
Microscale surface modifications for heat transfer enhancement.
Bostanci, Huseyin; Singh, Virendra; Kizito, John P; Rini, Daniel P; Seal, Sudipta; Chow, Louis C
2013-10-09
In this experimental study, two surface modification techniques were investigated for their effect on heat transfer enhancement. One of the methods employed the particle (grit) blasting to create microscale indentations, while the other used plasma spray coating to create microscale protrusions on Al 6061 (aluminum alloy 6061) samples. The test surfaces were characterized using scanning electron microscopy (SEM) and confocal scanning laser microscopy. Because of the surface modifications, the actual surface area was increased up to 2.8× compared to the projected base area, and the arithmetic mean roughness value (Ra) was determined to vary from 0.3 μm for the reference smooth surface to 19.5 μm for the modified surfaces. Selected samples with modified surfaces along with the reference smooth surface were then evaluated for their heat transfer performance in spray cooling tests. The cooling system had vapor-atomizing nozzles and used anhydrous ammonia as the coolant in order to achieve heat fluxes up to 500 W/cm(2) representing a thermal management setting for high power systems. Experimental results showed that the microscale surface modifications enhanced heat transfer coefficients up to 76% at 500 W/cm(2) compared to the smooth surface and demonstrated the benefits of these practical surface modification techniques to enhance two-phase heat transfer process.
NASA SBIR abstracts of 1990 phase 1 projects
NASA Technical Reports Server (NTRS)
Schwenk, F. C.; Gilman, J. A.; Paige, J. B.
1991-01-01
The research objectives of the 280 projects placed under contract in the National Aeronautics and Space Administration (NASA) 1990 Small Business Innovation Research (SBIR) Phase 1 program are described. The basic document consists of edited, non-proprietary abstracts of the winning proposals submitted by small businesses in response to NASA's 1990 SBIR Phase 1 Program Solicitation. The abstracts are presented under the 15 technical topics within which Phase 1 proposals were solicited. Each project was assigned a sequential identifying number from 001 to 280, in order of its appearance in the body of the report. The document also includes Appendixes to provide additional information about the SBIR program and permit cross-reference in the 1990 Phase 1 projects by company name, location by state, principal investigator, NASA field center responsible for management of each project, and NASA contract number.
Composite, nanostructured, super-hydrophobic material
D'Urso, Brian R [Clinton, TN; Simpson, John T [Clinton, TN
2007-08-21
A hydrophobic disordered composite material having a protrusive surface feature includes a recessive phase and a protrusive phase, the recessive phase having a higher susceptibility to a preselected etchant than the protrusive phase, the composite material having an etched surface wherein the protrusive phase protrudes from the surface to form a protrusive surface feature, the protrusive feature being hydrophobic.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, L; Zhang, Y; Harris, W
2015-06-15
Purpose: To develop an automatic markerless 4D-CBCT projection sorting technique by using a patient respiratory motion model extracted from the planning 4D-CT images. Methods: Each phase of onboard 4D-CBCT is considered as a deformation of one phase of the prior planning 4D-CT. The deformation field map (DFM) is represented as a linear combination of three major deformation patterns extracted from the planning 4D-CT using principle component analysis (PCA). The coefficients of the PCA deformation patterns are solved by matching the digitally reconstructed radiograph (DRR) of the deformed volume to the onboard projection acquired. The PCA coefficients are solved for eachmore » single projection, and are used for phase sorting. Projections at the peaks of the Z direction coefficient are sorted as phase 1 and other projections are assigned into 10 phase bins by dividing phases equally between peaks. The 4D digital extended-cardiac-torso (XCAT) phantom was used to evaluate the proposed technique. Three scenarios were simulated, with different tumor motion amplitude (3cm to 2cm), tumor spatial shift (8mm SI), and tumor body motion phase shift (2 phases) from prior to on-board images. Projections were simulated over 180 degree scan-angle for the 4D-XCAT. The percentage of accurately binned projections across entire dataset was calculated to represent the phase sorting accuracy. Results: With a changed tumor motion amplitude from 3cm to 2cm, markerless phase sorting accuracy was 100%. With a tumor phase shift of 2 phases w.r.t. body motion, the phase sorting accuracy was 100%. With a tumor spatial shift of 8mm in SI direction, phase sorting accuracy was 86.1%. Conclusion: The XCAT phantom simulation results demonstrated that it is feasible to use prior knowledge and motion modeling technique to achieve markerless 4D-CBCT phase sorting. National Institutes of Health Grant No. R01-CA184173 Varian Medical System.« less
Fluorescent Penetrant INSPECTION—CLEANING Study Update
NASA Astrophysics Data System (ADS)
Eisenmann, D.; Brasche, L.
2009-03-01
Fluorescent penetrant inspection (FPI) is widely used in the aviation industry and other industries for surface-breaking crack detection. As with all inspection methods, adherence to the process parameters is critical to the successful detection of defects. There is variety of lubricants and surface coatings used in the aviation industry which must be removed prior to FPI. Before the FPI process begins, components are cleaned using a variety of cleaning methods which are selected based on the alloy and the soil types which must be removed. It is also important that the cleaning process not adversely affect the FPI process. From the first three phases of this project it has been found that a hot water rinse can aid in the detection process when using this nondestructive method.
Historical and Projected Surface Temperature over India during the 20th and 21st century.
Basha, Ghouse; Kishore, P; Ratnam, M Venkat; Jayaraman, A; Agha Kouchak, Amir; Ouarda, Taha B M J; Velicogna, Isabella
2017-06-07
Surface Temperature (ST) over India has increased by ~0.055 K/decade during 1860-2005 and follows the global warming trend. Here, the natural and external forcings (e.g., natural and anthropogenic) responsible for ST variability are studied from Coupled Model Inter-comparison phase 5 (CMIP5) models during the 20 th century and projections during the 21 st century along with seasonal variability. Greenhouse Gases (GHG) and Land Use (LU) are the major factors that gave rise to warming during the 20 th century. Anthropogenic Aerosols (AA) have slowed down the warming rate. The CMIP5 projection over India shows a sharp increase in ST under Representative Concentration Pathways (RCP) 8.5 where it reaches a maximum of 5 K by the end of the 21 st century. Under RCP2.6 emission scenarios, ST increases up to the year 2050 and decreases afterwards. The seasonal variability of ST during the 21 st century shows significant increase during summer. Analysis of rare heat and cold events for 2080-2099 relative to a base period of 1986-2006 under RCP8.5 scenarios reveals that both are likely to increase substantially. However, by controlling the regional AA and LU change in India, a reduction in further warming over India region might be achieved.
NASA Technical Reports Server (NTRS)
Bowling, Laura C.; Lettenmaier, Dennis P.; Nijssen, Bart; Polcher, Jan; Koster, Randal D.; Lohmann, Dag; Houser, Paul R. (Technical Monitor)
2002-01-01
The Project for Intercomparison of Land Surface Parameterization Schemes (PILPS) Phase 2(e) showed that in cold regions the annual runoff production in Land Surface Schemes (LSSs) is closely related to the maximum snow accumulation, which in turn is controlled in large part by winter sublimation. To help further explain the relationship between snow cover, turbulent exchanges and runoff production, a simple equivalent model-(SEM) was devised to reproduce the seasonal and annual fluxes simulated by 13 LSSs that participated in PILPS Phase 2(e). The design of the SEM relates the annual partitioning of precipitation and energy in the LSSs to three primary parameters: snow albedo, effective aerodynamic resistance and evaporation efficiency. Isolation of each of the parameters showed that the annual runoff production was most sensitive to the aerodynamic resistance. The SEM was somewhat successful in reproducing the observed LSS response to a decrease in shortwave radiation and changes in wind speed forcings. SEM parameters derived from the reduced shortwave forcings suggested that increased winter stability suppressed turbulent heat fluxes over snow. Because winter sensible heat fluxes were largely negative, reductions in winter shortwave radiation imply an increase in annual average sensible heat.
Citygml Modelling for Singapore 3d National Mapping
NASA Astrophysics Data System (ADS)
Soon, K. H.; Khoo, V. H. S.
2017-10-01
Since 2014, the Land Survey Division of Singapore Land Authority (SLA) has spearheaded a Whole-of-Government (WOG) 3D mapping project to create and maintain a 3D national map for Singapore. The implementation of the project is divided into two phases. The first phase of the project, which was based on airborne data collection, has produced 3D models for Relief, Building, Vegetation and Waterbody. This part of the work was completed in 2016. To complement the first phase, the second phase used mobile imaging and scanning technique. This phase is targeted to be completed by the mid of 2017 and is creating 3D models for Transportation, CityFurniture, Bridge and Tunnel. The project has extensively adopted the Open Geospatial Consortium (OGC)'s CityGML standard. Out of 10 currently supported thematic modules in CityGML 2.0, the project has implemented 8. The paper describes the adoption of CityGML in the project, and discusses challenges, data validations and management of the models.
NASA Astrophysics Data System (ADS)
McPherson, Michelle Yvonne; García-García, Almudena; José Cuesta-Valero, Francisco; Beltrami, Hugo; Hansen-Ketchum, Patti; MacDougall, Donna; Hume Ogden, Nicholas
2017-04-01
A number of studies have assessed possible climate change impacts on the Lyme disease vector, Ixodes scapularis. However, most have used surface air temperature from only one climate model simulation and/or one emission scenario, representing only one possible climate future. We quantified effects of different Representative Concentration Pathway (RCP) and climate model outputs on the projected future changes in the basic reproduction number (R0) of I. scapularis to explore uncertainties in future R0 estimates. We used surface air temperature generated by a complete set of General Circulation Models from the Coupled Model Intercomparison Project Phase 5 (CMIP5) to hindcast historical and forecast future effects of climate change on the R0 of I. scapularis. As in previous studies, R0 of I. scapularis increased with a warming climate under future projected climate. Increases in the multi-model mean R0 values showed significant changes over time under all RCP scenarios, however; only the estimated R0 mean values between RCP6.0 and RCP8.5 showed statistically significant differences. Our results highlight the potential for climate change to have an effect on future Lyme disease risk in Canada even if the Paris Agreement's goal to keep global warming below 2°C is achieved, although mitigation reducing emissions from RCP8.5 levels to those of RCP6.0 or less would be expected to slow tick invasion after the 2030s. On-going planning is needed to inform and guide adaptation in light of the projected range of possible futures.
An anatomy of the projected North Atlantic warming hole in CMIP5 models
NASA Astrophysics Data System (ADS)
Menary, Matthew B.; Wood, Richard A.
2018-04-01
Global mean surface air temperature has increased over the past century and climate models project this trend to continue. However, the pattern of change is not homogeneous. Of particular interest is the subpolar North Atlantic, which has cooled in recent years and is projected to continue to warm less rapidly than the global mean. This is often termed the North Atlantic warming hole (WH). In climate model projections, the development of the WH is concomitant with a weakening of the Atlantic meridional overturning circulation (AMOC). Here, we further investigate the possible link between the AMOC and WH and the competing drivers of vertical mixing and surface heat fluxes. Across a large ensemble of 41 climate models we find that the spatial structure of the WH varies considerably from model to model but is generally upstream of the simulated deep water formation regions. A heat budget analysis suggests the formation of the WH is related to changes in ocean heat transport. Although the models display a plethora of AMOC mean states, they generally predict a weakening and shallowing of the AMOC also consistent with the evolving depth structure of the WH. A lagged regression analysis during the WH onset phase suggests that reductions in wintertime mixing lead a weakening of the AMOC by 5 years in turn leading initiation of the WH by 5 years. Inter-model differences in the evolution and structure of the WH are likely to lead to somewhat different projected climate impacts in nearby Europe and North America.
SH-2F LAMPS Instructional Systems Development: Phase II. Final Report.
ERIC Educational Resources Information Center
Gibbons, Andrew S.; Hymes, Jonah P.
This project was one of four aircrew training development projects in a continuing study of the methodology, effectiveness, and resource requirements of the Instructional Systems Development (ISD) process. This report covers the Phase II activities of a two-phase project for the development of aircrew training for SH-2F anti-submarine warfare…
The National Council on Crime and Delinquency NewGate Resource Center. Final Report.
ERIC Educational Resources Information Center
Herron, Rex; Muir, John
The origin and development of Project NewGate are described from 1971-74. (The project presents a model program of higher education for incarcerated offenders, consisting of the in-prison phase, transitional phase, and release phase.) Specific project characteristics are discussed and include a 4-year academic program for prison inmates; an…
Lafayette Parish Cooperative Jail Project--LPCJP. Phase III Final Report.
ERIC Educational Resources Information Center
Lafayette Parish School Board, LA.
A three-phase project was conducted to further the education of inmates in the Lafayette (Louisiana) Parish Correctional Center. Phase I of the project was designed to prepare inmates to be eligible to take the General Educational Development (GED) test, and/or to teach life-coping skills so that they would better function in society upon their…
Kittelmann, Jörg; Lang, Katharina M H; Ottens, Marcel; Hubbuch, Jürgen
2017-01-27
Quantitative structure-activity relationship (QSAR) modeling for prediction of biomolecule parameters has become an established technique in chromatographic purification process design. Unfortunately available descriptor sets fail to describe the orientation of biomolecules and the effects of ionic strength in the mobile phase on the interaction with the stationary phase. The literature describes several special descriptors used for chromatographic retention modeling, all of these do not describe the screening of electrostatic potential by the mobile phase in use. In this work we introduce two new approaches of descriptor calculations, namely surface patches and plane projection, which capture an oriented binding to charged surfaces and steric hindrance of the interaction with chromatographic ligands with regard to electrostatic potential screening by mobile phase ions. We present the use of the developed descriptor sets for predictive modeling of Langmuir isotherms for proteins at different pH values between pH 5 and 10 and varying ionic strength in the range of 10-100mM. The resulting model has a high correlation of calculated descriptors and experimental results, with a coefficient of determination of 0.82 and a predictive coefficient of determination of 0.92 for unknown molecular structures and conditions. The agreement of calculated molecular interaction orientations with both, experimental results as well as molecular dynamic simulations from literature is shown. The developed descriptors provide the means for improved QSAR models of chromatographic processes, as they reflect the complex interactions of biomolecules with chromatographic phases. Copyright © 2016 Elsevier B.V. All rights reserved.
The PRISM4 (mid-Piacenzian) Palaeoenvironmental Reconstruction
NASA Technical Reports Server (NTRS)
Dowsett, Harry; Dolan, Aisling; Rowley, David; Moucha, Robert; Forte, Alessandro M.; Mitrovica, Jerry X.; Pound, Matthew; Salzmann, Ulrich; Robinson, Marci; Chandler, Mark;
2016-01-01
The mid-Piacenzian is known as a period of relative warmth when compared to the present day. A comprehensive understanding of conditions during the Piacenzian serves as both a conceptual model and a source for boundary conditions as well as means of verification of global climate model experiments. In this paper we present the PRISM4 reconstruction, a paleoenvironmental reconstruction of the mid-Piacenzian (approximately 3 Ma) containing data for paleogeography, land and sea ice, sea-surface temperature, vegetation, soils, and lakes. Our retrodicted paleogeography takes into account glacial isostatic adjustments and changes in dynamic topography. Soils and lakes, both significant as land surface features, are introduced to the PRISM reconstruction for the first time. Sea-surface temperature and vegetation reconstructions are unchanged but now have confidence assessments. The PRISM4 reconstruction is being used as boundary condition data for the Pliocene Model Intercomparison Project Phase 2 (PlioMIP2) experiments.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gyenis, András; Inoue, Hiroyuki; Jeon, Sangjun
Following the intense studies on topological insulators, significant efforts have recently been devoted to the search for gapless topological systems. These materials not only broaden the topological classification of matter but also provide a condensed matter realization of various relativistic particles and phenomena previously discussed mainly in high energy physics. Weyl semimetals host massless, chiral, low-energy excitations in the bulk electronic band structure, whereas a symmetry protected pair of Weyl fermions gives rise to massless Dirac fermions.Weemployed scanning tunneling microscopy/spectroscopy to explore the behavior of electronic states both on the surface and in the bulk of topological semimetal phases. Bymore » mapping the quasiparticle interference (QPI) and emerging Landau levels at high magnetic field in Dirac semimetals Cd 3As 2 and Na 3Bi, we observed extended Dirac-like bulk electronic bands. QPI imaged on Weyl semimetal TaAs demonstrated the predicted momentum dependent delocalization of Fermi arc surface states in the vicinity of the surface projected Weyl nodes.« less
North Atlantic climate model bias influence on multiyear predictability
NASA Astrophysics Data System (ADS)
Wu, Y.; Park, T.; Park, W.; Latif, M.
2018-01-01
The influences of North Atlantic biases on multiyear predictability of unforced surface air temperature (SAT) variability are examined in the Kiel Climate Model (KCM). By employing a freshwater flux correction over the North Atlantic to the model, which strongly alleviates both North Atlantic sea surface salinity (SSS) and sea surface temperature (SST) biases, the freshwater flux-corrected integration depicts significantly enhanced multiyear SAT predictability in the North Atlantic sector in comparison to the uncorrected one. The enhanced SAT predictability in the corrected integration is due to a stronger and more variable Atlantic Meridional Overturning Circulation (AMOC) and its enhanced influence on North Atlantic SST. Results obtained from preindustrial control integrations of models participating in the Coupled Model Intercomparison Project Phase 5 (CMIP5) support the findings obtained from the KCM: models with large North Atlantic biases tend to have a weak AMOC influence on SAT and exhibit a smaller SAT predictability over the North Atlantic sector.
Television experiment for Mariner Mars 1971
Masursky, H.; Batson, R.; Borgeson, W.; Carr, M.; McCauley, J.; Milton, D.; Wildey, R.; Wilhelms, D.; Murray, B.; Horowitz, N.; Leighton, R.; Sharp, R.; Thompson, W.; Briggs, G.; Chandeysson, P.; Shipley, E.; Sagan, C.; Pollack, J.; Lederberg, J.; Levinthal, E.; Hartmann, W.; McCord, T.; Smith, B.; Davies, M.; De Vaucouleurs, G.; Leovy, C.
1970-01-01
The Television Experiment objectives are to provide imaging data which will complement previously gathered data and extend our knowledge of Mars. The two types of investigations will be fixed-feature (for mapping) and variable-feature (for surface and atmospheric changes). Two cameras with a factor-of-ten difference in resolution will be used on each spacecraft for medium- and high-resolution imagery. Mapping of 70% of the planet's surface will be provided by medium-resolution imagery. Spot coverage of about 5% of the surface will be possible with the high-resolution imagery. The experiment's 5 Principal Investigators and 21 Co-Investigators are organized into a team. Scientific disciplines and technical task groups have been formed to provide the formulation of experiment requirements for mission planning and instrument development. It is expected that the team concept will continue through the operational and reporting phases of the Mariner Mars 1971 Project. ?? 1970.
The PRISM4 (mid-Piacenzian) paleoenvironmental reconstruction
Dowsett, Harry J.; Dolan, Aisling M.; Rowley, David; Moucha, Robert; Forte, Alessandro; Mitrovica, Jerry X.; Pound, Matthew; Salzmann, Ulrich; Robinson, Marci M.; Chandler, Mark; Foley, Kevin M.; Haywood, Alan M.
2016-01-01
The mid-Piacenzian is known as a period of relative warmth when compared to the present day. A comprehensive understanding of conditions during the Piacenzian serves as both a conceptual model and a source for boundary conditions as well as means of verification of global climate model experiments. In this paper we present the PRISM4 reconstruction, a paleoenvironmental reconstruction of the mid-Piacenzian ( ∼ 3 Ma) containing data for paleogeography, land and sea ice, sea-surface temperature, vegetation, soils, and lakes. Our retrodicted paleogeography takes into account glacial isostatic adjustments and changes in dynamic topography. Soils and lakes, both significant as land surface features, are introduced to the PRISM reconstruction for the first time. Sea-surface temperature and vegetation reconstructions are unchanged but now have confidence assessments. The PRISM4 reconstruction is being used as boundary condition data for the Pliocene Model Intercomparison Project Phase 2 (PlioMIP2) experiments.
Current status of the joint Mayo Clinic-IBM PACS project
NASA Astrophysics Data System (ADS)
Hangiandreou, Nicholas J.; Williamson, Byrn, Jr.; Gehring, Dale G.; Persons, Kenneth R.; Reardon, Frank J.; Salutz, James R.; Felmlee, Joel P.; Loewen, M. D.; Forbes, Glenn S.
1994-05-01
A multi-phase collaboration between Mayo Clinic and IBM-Rochester was undertaken, with the goal of developing a picture archiving and communication system for routine clinical use in the Radiology Department. The initial phase of this project (phase 0) was started in 1988. The current system has been fully integrated into the clinical practice and, to date, over 6.5 million images from 16 imaging modalities have been archived. Phase 3 of this project has recently concluded.
Prey-sensing and orientational behaviors of sand scorpions
NASA Astrophysics Data System (ADS)
Brownell, Philip
2000-03-01
Sand scorpions use exquisitely sensitive vibrational and chemosensory systems to locate prey and identify prospective mates active on the sand surface. Prey location is determined by input to a static array of 8 vibration-sensitive receptors, each responding as phase-locked accelerometers to compressional and surface waves conducted through sand. Angular orientation of the target is determined from passing surface (Rayleigh) waves, target distance possibly from the time delay between arrival of compressional and surface waves. For localization and identification of prospective mates, male scorpions use sexually dimorphic chemosensory appendages, the pectines, which are swept over a static stimulus field (chemical trail deposited on sand). These organs support a 2D array of closely-spaced (freq = 100/mm) sensilla containing more than 10^6 neurons, all projecting with great topographic precision to the central nervous system. Movement of this sensory array over a static stimulus field creates timing within the sensory signal. The potential importance of timing as a means of increasing sensitivity and selectivity of sensory response in two distinctly different modes is discussed.
NASA Astrophysics Data System (ADS)
Cohen, K. K.; Klara, S. M.; Srivastava, R. D.
2004-12-01
The U.S. Department of Energy's (U.S. DOE's) Carbon Sequestration Program is developing state-of-the-science technologies for measurement, mitigation, and verification (MM&V) in field operations of geologic sequestration. MM&V of geologic carbon sequestration operations will play an integral role in the pre-injection, injection, and post-injection phases of carbon capture and storage projects to reduce anthropogenic greenhouse gas emissions. Effective MM&V is critical to the success of CO2 storage projects and will be used by operators, regulators, and stakeholders to ensure safe and permanent storage of CO2. In the U.S. DOE's Program, Carbon sequestration MM&V has numerous instrumental roles: Measurement of a site's characteristics and capability for sequestration; Monitoring of the site to ensure the storage integrity; Verification that the CO2 is safely stored; and Protection of ecosystems. Other drivers for MM&V technology development include cost-effectiveness, measurement precision, and frequency of measurements required. As sequestration operations are implemented in the future, it is anticipated that measurements over long time periods and at different scales will be required; this will present a significant challenge. MM&V sequestration technologies generally utilize one of the following approaches: below ground measurements; surface/near-surface measurements; aerial and satellite imagery; and modeling/simulations. Advanced subsurface geophysical technologies will play a primary role for MM&V. It is likely that successful MM&V programs will incorporate multiple technologies including but not limited to: reservoir modeling and simulations; geophysical techniques (a wide variety of seismic methods, microgravity, electrical, and electromagnetic techniques); subsurface fluid movement monitoring methods such as injection of tracers, borehole and wellhead pressure sensors, and tiltmeters; surface/near surface methods such as soil gas monitoring and infrared sensors and; aerial and satellite imagery. This abstract will describe results, similarities, and contrasts for funded studies from the U.S. DOE's Carbon Sequestration Program including examples from the Sleipner North Sea Project, the Canadian Weyburn Field/Dakota Gasification Plant Project, the Frio Formation Texas Project, and Yolo County Bioreactor Landfill Project. The abstract will also address the following: How are the terms ``measurement,'' ``mitigation''and ``verification'' defined in the Program? What is the U.S. DOE's Carbon Sequestration Program Roadmap and what are the Roadmap goals for MM&V? What is the current status of MM&V technologies?
Large active mirror in aluminium
NASA Astrophysics Data System (ADS)
Leblanc, Jean-M.; Rozelot, Jean-Pierre
1991-11-01
The Large Active Mirrors in Aluminum Project (LAMA) is intended as a metallic alternative to the conventional glass mirrors. This alternative is to bring about definite improvements in terms of lower cost, shorter manufacturing, and reduced brittleness. Combined in a system approach that integrates design, development, and manufacturing of both the aluminum meniscus and its active support, the LAMA project is a technologically consistent product for astronomical and laser telescopes. Large size mirrors can be delivered, up to 8 m diameter. Recent progress in active optics makes possible control, as well as real-time adjustment, of a metallic mirror's deformations, especially those induced by temperature variations and/or aging. It also enables correction of whatever low-frequency surface waves escaped polishing. Besides, the manufacturing process to produce the aluminum segments together with the electron welding technique ensure the material's homogeneity. Quality of the surface condition will result from optimized implementation of the specific aluminum machining and polishing techniques. This paper highlights the existing aluminum realizations compared to glass mirrors, and gives the main results obtained during a feasibility demonstration phase, based on 8 m mirror requirements.
Mechanisms and Dynamics of Abiotic and Biotic Interactions at Environmental Interfaces
DOE Office of Scientific and Technical Information (OSTI.GOV)
Roso, Kevin M.
The Stanford EMSI (SEMSI) was established in 2004 through joint funding by the National Science Foundation and the OBER-ERSD. It encompasses a number of universities and national laboratories. The PNNL component of the SEMSI is funded by ERSD and is the focus of this report. This component has the objective of providing theory support to the SEMSI by bringing computational capabilities and expertise to bear on important electron transfer problems at mineral/water and mineral/microbe interfaces. PNNL staff member Dr. Kevin Rosso, who is also ''matrixed'' into the Environmental Molecular Sciences Laboratory (EMSL) at PNNL, is a co-PI on the SEMSImore » project and the PNNL lead. The EMSL computational facilities being applied to the SEMSI project include the 11.8 teraflop massively-parallel supercomputer. Science goals of this EMSL/SEMSI partnership include advancing our understanding of: (1) The kinetics of U(VI) and Cr(VI) reduction by aqueous and solid-phase Fe(II), (2) The structure of mineral surfaces in equilibrium with solution, and (3) Mechanisms of bacterial electron transfer to iron oxide surfaces via outer-membrane cytochromes.« less
Error Cost Escalation Through the Project Life Cycle
NASA Technical Reports Server (NTRS)
Stecklein, Jonette M.; Dabney, Jim; Dick, Brandon; Haskins, Bill; Lovell, Randy; Moroney, Gregory
2004-01-01
It is well known that the costs to fix errors increase as the project matures, but how fast do those costs build? A study was performed to determine the relative cost of fixing errors discovered during various phases of a project life cycle. This study used three approaches to determine the relative costs: the bottom-up cost method, the total cost breakdown method, and the top-down hypothetical project method. The approaches and results described in this paper presume development of a hardware/software system having project characteristics similar to those used in the development of a large, complex spacecraft, a military aircraft, or a small communications satellite. The results show the degree to which costs escalate, as errors are discovered and fixed at later and later phases in the project life cycle. If the cost of fixing a requirements error discovered during the requirements phase is defined to be 1 unit, the cost to fix that error if found during the design phase increases to 3 - 8 units; at the manufacturing/build phase, the cost to fix the error is 7 - 16 units; at the integration and test phase, the cost to fix the error becomes 21 - 78 units; and at the operations phase, the cost to fix the requirements error ranged from 29 units to more than 1500 units
Moses Lake Fishery Restoration Project : FY 1999 Annual Report.
DOE Office of Scientific and Technical Information (OSTI.GOV)
None given
2000-12-01
The Moses Lake Project consists of 3 phases. Phase 1 is the assessment of all currently available physical and biological information, the collection of baseline biological data, the formulation of testable hypotheses, and the development of a detailed study plan to test the hypotheses. Phase 2 is dedicated to the implementation of the study plan including data collection, hypotheses testing, and the formulation of a management plan. Phase 3 of the project is the implementation of the management plan, monitoring and evaluation of the implemented recommendations. The project intends to restore the failed recreational fishery for panfish species (black crappie,more » bluegill and yellow perch) in Moses Lake as off site mitigation for lost recreational fishing opportunities for anadromous species in the upper Columbia River. This report summarizes the results of Phase 1 investigations and presents the study plan directed at initiating Phase 2 of the project. Phase 1of the project culminates with the formulation of testable hypotheses directed at investigating possible limiting factors to the production of panfish in Moses Lake. The limiting factors to be investigated will include water quality, habitat quantity and quality, food limitations, competition, recruitment, predation, over harvest, environmental requirements, and the physical and chemical limitations of the system in relation to the fishes.« less
TA 55 Reinvestment Project II Phase C Update Project Status May 23, 2017
DOE Office of Scientific and Technical Information (OSTI.GOV)
Giordano, Anthony P.
The TA-55 Reinvestment Project (TRP) II Phase C is a critical infrastructure project focused on improving safety and reliability of the Los Alamos National Laboratory (LANL) TA-55 Complex. The Project recapitalizes and revitalizes aging and obsolete facility and safety systems providing a sustainable nuclear facility for National Security Missions.
OBJECTIVES, DESIGN, AND PRELIMINARY RESULTS FROM THE ATLANTA SUPERSITE PROJECT
The Atlanta Supersites project is the first of two Supersites projects to be established during Phase I of EPA's Supersites Program; Phase II is being established through a Request for Assistance. The other initial project is in Fresno, California. The Supersite Program is part o...
Phase III of Early Restoration | NOAA Gulf Spill Restoration
information about this phase of Early Restoration, including fact sheets on each project. The final Phase III 44 projects are documented in a final Record of Decision. Information about Phase III of Early Archive Home Phase III of Early Restoration Phase III of Early Restoration Beach habitat would be restored
High performance sapphire windows
NASA Technical Reports Server (NTRS)
Bates, Stephen C.; Liou, Larry
1993-01-01
High-quality, wide-aperture optical access is usually required for the advanced laser diagnostics that can now make a wide variety of non-intrusive measurements of combustion processes. Specially processed and mounted sapphire windows are proposed to provide this optical access to extreme environment. Through surface treatments and proper thermal stress design, single crystal sapphire can be a mechanically equivalent replacement for high strength steel. A prototype sapphire window and mounting system have been developed in a successful NASA SBIR Phase 1 project. A large and reliable increase in sapphire design strength (as much as 10x) has been achieved, and the initial specifications necessary for these gains have been defined. Failure testing of small windows has conclusively demonstrated the increased sapphire strength, indicating that a nearly flawless surface polish is the primary cause of strengthening, while an unusual mounting arrangement also significantly contributes to a larger effective strength. Phase 2 work will complete specification and demonstration of these windows, and will fabricate a set for use at NASA. The enhanced capabilities of these high performance sapphire windows will lead to many diagnostic capabilities not previously possible, as well as new applications for sapphire.
High performance sapphire windows
NASA Astrophysics Data System (ADS)
Bates, Stephen C.; Liou, Larry
1993-02-01
High-quality, wide-aperture optical access is usually required for the advanced laser diagnostics that can now make a wide variety of non-intrusive measurements of combustion processes. Specially processed and mounted sapphire windows are proposed to provide this optical access to extreme environment. Through surface treatments and proper thermal stress design, single crystal sapphire can be a mechanically equivalent replacement for high strength steel. A prototype sapphire window and mounting system have been developed in a successful NASA SBIR Phase 1 project. A large and reliable increase in sapphire design strength (as much as 10x) has been achieved, and the initial specifications necessary for these gains have been defined. Failure testing of small windows has conclusively demonstrated the increased sapphire strength, indicating that a nearly flawless surface polish is the primary cause of strengthening, while an unusual mounting arrangement also significantly contributes to a larger effective strength. Phase 2 work will complete specification and demonstration of these windows, and will fabricate a set for use at NASA. The enhanced capabilities of these high performance sapphire windows will lead to many diagnostic capabilities not previously possible, as well as new applications for sapphire.
Phase coherent transport in hybrid superconductor-topological insulator devices
NASA Astrophysics Data System (ADS)
Finck, Aaron
2015-03-01
Heterostructures of superconductors and topological insulators are predicted to host unusual zero energy bound states known as Majorana fermions, which can robustly store and process quantum information. Here, I will discuss our studies of such heterostructures through phase-coherent transport, which can act as a unique probe of Majorana fermions. We have extensively explored topological insulator Josephson junctions through SQUID and single-junction diffraction patterns, whose unusual behavior give evidence for low-energy Andreev bound states. In topological insulator devices with closely spaced normal and superconducting leads, we observe prominent Fabry-Perot oscillations, signifying gate-tunable, quasi-ballistic transport that can elegantly interact with Andreev reflection. Superconducting disks deposited on the surface of a topological insulator generate Aharonov-Bohm-like oscillations, giving evidence for unusual states lying near the interface between the superconductor and topological insulator surface. Our results point the way towards sophisticated interferometers that can detect and read out the state of Majorana fermions in topological systems. This work was done in collaboration with Cihan Kurter, Yew San Hor, and Dale Van Harlingen. We acknowledge funding from Microsoft Project Q.
Streamline Your Project: A Lifecycle Model.
ERIC Educational Resources Information Center
Viren, John
2000-01-01
Discusses one approach to project organization providing a baseline lifecycle model for multimedia/CBT development. This variation of the standard four-phase model of Analysis, Design, Development, and Implementation includes a Pre-Analysis phase, called Definition, and a Post-Implementation phase, known as Maintenance. Each phase is described.…
NASA Astrophysics Data System (ADS)
Zhou, Wenyu; Xie, Shang-Ping
2017-08-01
Global climate models (GCMs) have long suffered from biases of excessive tropical precipitation in the Southern Hemisphere (SH). The severity of the double-Intertropical Convergence Zone (ITCZ) bias, defined here as the interhemispheric difference in zonal mean tropical precipitation, varies strongly among models in the Coupled Model Intercomparison Project Phase 5 (CMIP5) ensemble. Models with a more severe double-ITCZ bias feature warmer tropical sea surface temperature (SST) in the SH, coupled with weaker southeast trades. While previous studies focus on coupled ocean-atmosphere interactions, here we show that the intermodel spread in the severity of the double-ITCZ bias is closely related to land surface temperature biases, which can be further traced back to those in the Atmosphere Model Intercomparison Project (AMIP) simulations. By perturbing land temperature in models, we demonstrate that cooler land can indeed lead to a more severe double-ITCZ bias by inducing the above coupled SST-trade wind pattern in the tropics. The response to land temperature can be consistently explained from both the dynamic and energetic perspectives. Although this intermodel spread from the land temperature variation does not account for the ensemble model mean double-ITCZ bias, identifying the land temperature effect provides insights into simulating a realistic ITCZ for the right reasons.
NASA Technical Reports Server (NTRS)
Kuhl, Christoper A.
2009-01-01
The Aerial Regional-Scale Environmental Survey (ARES) is a Mars exploration mission concept with the goal of taking scientific measurements of the atmosphere, surface, and subsurface of Mars by using an airplane as the payload platform. ARES team first conducted a Phase-A study for a 2007 launch opportunity, which was completed in May 2003. Following this study, significant efforts were undertaken to reduce the risk of the atmospheric flight system, under the NASA Langley Planetary Airplane Risk Reduction Project. The concept was then proposed to the Mars Scout program in 2006 for a 2011 launch opportunity. This paper summarizes the design and development of the ARES airplane propulsion subsystem beginning with the inception of the ARES project in 2002 through the submittal of the Mars Scout proposal in July 2006.
Descent Stage of Mars Science Laboratory During Assembly
NASA Technical Reports Server (NTRS)
2008-01-01
This image from early October 2008 shows personnel working on the descent stage of NASA's Mars Science Laboratory inside the Spacecraft Assembly Facility at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The descent stage will provide rocket-powered deceleration for a phase of the arrival at Mars after the phases using the heat shield and parachute. When it nears the surface, the descent stage will lower the rover on a bridle the rest of the way to the ground. The larger three of the orange spheres in the descent stage are fuel tanks. The smaller two are tanks for pressurant gas used for pushing the fuel to the rocket engines. JPL, a division of the California Institute of Technology, manages the Mars Science Laboratory Project for the NASA Science Mission Directorate, Washington.Sears Point Tidal Marsh Restoration Project: Phase I
Information about the SFBWQP Sears Point Tidal Marsh Restoration Project: Phase I project, part of an EPA competitive grant program to improve SF Bay water quality focused on restoring impaired waters and enhancing aquatic resources.
User systems guidelines for software projects
DOE Office of Scientific and Technical Information (OSTI.GOV)
Abrahamson, L.
1986-04-01
This manual presents guidelines for software standards which were developed so that software project-development teams and management involved in approving the software could have a generalized view of all phases in the software production procedure and the steps involved in completing each phase. Guidelines are presented for six phases of software development: project definition, building a user interface, designing software, writing code, testing code, and preparing software documentation. The discussions for each phase include examples illustrating the recommended guidelines. 45 refs. (DWL)
NASA Astrophysics Data System (ADS)
Gorthi, Sai Siva; Rajshekhar, G.; Rastogi, Pramod
2010-04-01
For three-dimensional (3D) shape measurement using fringe projection techniques, the information about the 3D shape of an object is encoded in the phase of a recorded fringe pattern. The paper proposes a high-order instantaneous moments based method to estimate phase from a single fringe pattern in fringe projection. The proposed method works by approximating the phase as a piece-wise polynomial and subsequently determining the polynomial coefficients using high-order instantaneous moments to construct the polynomial phase. Simulation results are presented to show the method's potential.
Phase 2 of the Array Automated Assembly Task for the Low Cost Solar Array Project
NASA Technical Reports Server (NTRS)
Campbell, R. B.; Rai-Choundhury, P.; Seman, E. J.; Rohatgi, A.; Davis, J. R.; Ostroski, J. W.; Stapleton, R. E.
1979-01-01
Two process specifications supplied by contractors were tested. The aluminum silk screening process resulted in cells comparable to those from sputtered Al. The electroless plating of contacts specification could be used only with extensive modification. Several experiments suggest that there is some degradation of the front junction during the Al back surface field (BSF) fabrication. A revised process sequence was defined which incorporates Al BSF formation. A cost analysis of this process yielded a selling price of $0.75/watt peak in 1980.
1980-10-01
16 7.2 Remedial Measures 17 APPENDIX A - MAPS Plate A-1 Vicinity Topography Plate A-2 Location Map Plate A-3 Seismic Map APPENDIX B - PHOTOGRAPHS...reservoir surface area, and elvton-storage data were developed from the USGS Cape Girardeau, Missouri 7-1/2 minute topographic quadrangle map . The...project file. CA -18- APPENDIX A MAPS II ./ \\v 14,.. MITE LSRIES ILUOOtS HC Scal in eetVICIITYTOPOGRAPHY Contur Itoral -10’MO 30533
1987-12-01
d the location documented on a project site map . c. Split all water , sedi:-ent and soil p~ts as -art of the ccntractor’s specific Quality Assurance...regional/site specific hydrcg.volog-y, -]Il And boring logs, data from water level surveys, grcundwater surface and gradient maps , water quality and...COMMAND COMMAND BIOENVIRONMENTAL ENGINEER (AFSC/SGPB) ANDR-WS AIR FORCE BASE, DC 20334-5000 DECEMBER 1987 PREPARED BY RADIAN CORPORATION 8501 MO-PAC
High lateral resolution exploration using surface waves from noise records
NASA Astrophysics Data System (ADS)
Chávez-García, Francisco José Yokoi, Toshiaki
2016-04-01
Determination of the shear-wave velocity structure at shallow depths is a constant necessity in engineering or environmental projects. Given the sensitivity of Rayleigh waves to shear-wave velocity, subsoil structure exploration using surface waves is frequently used. Methods such as the spectral analysis of surface waves (SASW) or multi-channel analysis of surface waves (MASW) determine phase velocity dispersion from surface waves generated by an active source recorded on a line of geophones. Using MASW, it is important that the receiver array be as long as possible to increase the precision at low frequencies. However, this implies that possible lateral variations are discarded. Hayashi and Suzuki (2004) proposed a different way of stacking shot gathers to increase lateral resolution. They combined strategies used in MASW with the common mid-point (CMP) summation currently used in reflection seismology. In their common mid-point with cross-correlation method (CMPCC), they cross-correlate traces sharing CMP locations before determining phase velocity dispersion. Another recent approach to subsoil structure exploration is based on seismic interferometry. It has been shown that cross-correlation of a diffuse field, such as seismic noise, allows the estimation of the Green's Function between two receivers. Thus, a virtual-source seismic section may be constructed from the cross-correlation of seismic noise records obtained in a line of receivers. In this paper, we use the seismic interferometry method to process seismic noise records obtained in seismic refraction lines of 24 geophones, and analyse the results using CMPCC to increase the lateral resolution of the results. Cross-correlation of the noise records allows reconstructing seismic sections with virtual sources at each receiver location. The Rayleigh wave component of the Green's Functions is obtained with a high signal-to-noise ratio. Using CMPCC analysis of the virtual-source seismic lines, we are able to identify lateral variations of phase velocity inside the seismic line, and increase the lateral resolution compared with results of conventional analysis.
Crystalline and amorphous H2O on Charon
NASA Astrophysics Data System (ADS)
Dalle Ore, Cristina M.; Cruikshank, Dale P.; Grundy, Will M.; Ennico, Kimberly; Olkin, Catherine B.; Stern, S. Alan; Young, Leslie A.; Weaver, Harold A.
2015-11-01
Charon, the largest satellite of Pluto, is a gray-colored icy world covered mostly in H2O ice, with spectral evidence for NH3, as previously reported (Cook et al. 2007, Astrophys. J. 663, 1406-1419 Merlin, et al. 2010, Icarus, 210, 930; Cook, et al. 2014, AAS/Division for Planetary Sciences Meeting Abstracts, 46, #401.04). Images from the New Horizons spacecraft reveal a surface with terrains of widely different ages and a moderate degree of localized coloration. The presence of H2O ice in its crystalline form (Brown & Calvin 2000 Science 287, 107-109; Buie & Grundy 2000 Icarus 148, 324-339; Merlin et al, 2010) along with NH3 is consistent with a fresh surface.The phase of H2O ice is a key tracer of variations in temperature and physical conditions on the surface of outer Solar System objects. At Charon’s surface temperature H2O is expected to be amorphous, but ground-based observations (e.g., Merlin et al. 2010) show a clearly crystalline signature. From laboratory experiments it is known that amorphous H2O ice becomes crystalline at temperatures of ~130 K. Other mechanisms that can change the phase of the ice from amorphous to crystalline include micro-meteoritic bombardment (Porter et al. 2010, Icarus, 208, 492) or resurfacing processes such as cryovolcanism.New Horizons observed Charon with the LEISA imaging spectrometer, part of the Ralph instrument (Reuter, D.C., Stern, S.A., Scherrer, J., et al. 2008, Space Science Reviews, 140, 129). Making use of high spatial resolution (better than 10 km/px) and spectral resolving power of 240 in the wavelength range 1.25-2.5 µm, and 560 in the range 2.1-2.25 µm, we report on an analysis of the phase of H2O ice on parts of Charon’s surface with a view to investigate the recent history and evolution of this small but intriguing object.This work was supported by NASA’s New Horizons project.
1987-06-15
001 GENERAL DYNAMICS 00 FORT WORTH DIVISION INDUSTRIAL TECHNOLOGY MODERNIZATION PROGRAM Phase 2 Final Project Repc t JUNG 0 ?7 PROJECT 28 AUTOMATION...DYNAMICS FORT WORTH DIVISION INDUSTRIAL TECHNOLOGY MODERNIZATION PROGRAM Phase 2 Final Project Report PROJECT 28 AUTOMATION OF RECEIVING, RECEIVING...13 6 PROJECT ASSUMPTIONS 20 7 PRELIMINARY/FINAL DESIGN AND FINDINGS 21 8 SYSTEM/EQUIPMENT/MACHINING SPECIFICATIONS 37 9 VENDOR/ INDUSTRY ANALYSIS
Unconventional transformation of spin Dirac phase across a topological quantum phase transition
Xu, Su-Yang; Neupane, Madhab; Belopolski, Ilya; Liu, Chang; Alidoust, Nasser; Bian, Guang; Jia, Shuang; Landolt, Gabriel; Slomski, Batosz; Dil, J. Hugo; Shibayev, Pavel P.; Basak, Susmita; Chang, Tay-Rong; Jeng, Horng-Tay; Cava, Robert J.; Lin, Hsin; Bansil, Arun; Hasan, M. Zahid
2015-01-01
The topology of a topological material can be encoded in its surface states. These surface states can only be removed by a bulk topological quantum phase transition into a trivial phase. Here we use photoemission spectroscopy to image the formation of protected surface states in a topological insulator as we chemically tune the system through a topological transition. Surprisingly, we discover an exotic spin-momentum locked, gapped surface state in the trivial phase that shares many important properties with the actual topological surface state in anticipation of the change of topology. Using a spin-resolved measurement, we show that apart from a surface bandgap these states develop spin textures similar to the topological surface states well before the transition. Our results offer a general paradigm for understanding how surface states in topological phases arise from a quantum phase transition and are suggestive for the future realization of Weyl arcs, condensed matter supersymmetry and other fascinating phenomena in the vicinity of a quantum criticality. PMID:25882717
Unconventional transformation of spin Dirac phase across a topological quantum phase transition
Xu, Su -Yang; Neupane, Madhab; Belopolski, Ilya; ...
2015-04-17
The topology of a topological material can be encoded in its surface states. These surface states can only be removed by a bulk topological quantum phase transition into a trivial phase. Here we use photoemission spectroscopy to image the formation of protected surface states in a topological insulator as we chemically tune the system through a topological transition. Surprisingly, we discover an exotic spin-momentum locked, gapped surface state in the trivial phase that shares many important properties with the actual topological surface state in anticipation of the change of topology. Using a spin-resolved measurement, we show that apart from amore » surface bandgap these states develop spin textures similar to the topological surface states well before the transition. Our results provide a general paradigm for understanding how surface states in topological phases arise from a quantum phase transition and are suggestive for the future realization of Weyl arcs, condensed matter supersymmetry and other fascinating phenomena in the vicinity of a quantum criticality.« less
Electronic construction collaboration system : phase III.
DOT National Transportation Integrated Search
2011-12-01
This phase of the electronic collaboration project involved two major efforts: 1) implementation of AEC Sync (formerly known as Attolist), a web-based project management system (WPMS), on the Broadway Viaduct Bridge Project and the Iowa Falls Arch Br...
Chattanooga SmartBus Project : phase 2 evaluation report
DOT National Transportation Integrated Search
2008-06-10
This report presents the results of Phase II of the national evaluation of the Chattanooga Area Regional Transportation Authoritys (CARTAs) SmartBus Project. The Smartbus Project is a comprehensive transit ITS program for the city of Chattanoog...
Manned Spacecraft Requirements for Materials and Processes
NASA Technical Reports Server (NTRS)
Vaughn, Timothy P.
2006-01-01
A major cause of project failure can be attributed to an emphasized focus on end products and inadequate attention to resolving development risks during the initial phases of a project. The initial phases of a project, which we will call the "study period", are critical to determining project scope and costs, and can make or break most projects. If the requirements are not defined adequately, how can the scope be adequately determined, also how can the costs of the entire project be effectively estimated, and how can the risk of project success be accurately assessed? Using the proper material specifications and standards and incorporating these specifications and standards in the design process should be considered inherently crucial to the technical success of a project as just as importantly, crucial to the cost and schedule success. This paper will intertwine several important aspects or considerations for project success: 1) Characteristics of a "Good Material Requirement"; 2) Linking material requirements to the implementation of "Design for Manufacturing"; techniques and 3) The importance of decomposing materials requirements during the study phase/development phase to mitigate project risk for the maturation of technologies before the building of hardware.
NASA Astrophysics Data System (ADS)
Chmiel, Malgorzata; Roux, Philippe; Herrmann, Philippe; Rondeleux, Baptiste; Wathelet, Marc
2018-05-01
We investigated the construction of diffraction kernels for surface waves using two-point convolution and/or correlation from land active seismic data recorded in the context of exploration geophysics. The high density of controlled sources and receivers, combined with the application of the reciprocity principle, allows us to retrieve two-dimensional phase-oscillation diffraction kernels (DKs) of surface waves between any two source or receiver points in the medium at each frequency (up to 15 Hz, at least). These DKs are purely data-based as no model calculations and no synthetic data are needed. They naturally emerge from the interference patterns of the recorded wavefields projected on the dense array of sources and/or receivers. The DKs are used to obtain multi-mode dispersion relations of Rayleigh waves, from which near-surface shear velocity can be extracted. Using convolution versus correlation with a grid of active sources is an important step in understanding the physics of the retrieval of surface wave Green's functions. This provides the foundation for future studies based on noise sources or active sources with a sparse spatial distribution.
NASA Technical Reports Server (NTRS)
Key, Jeff; Maslanik, James; Steffen, Konrad
1995-01-01
During the second phase project year we have made progress in the development and refinement of surface temperature retrieval algorithms and in product generation. More specifically, we have accomplished the following: (1) acquired a new advanced very high resolution radiometer (AVHRR) data set for the Beaufort Sea area spanning an entire year; (2) acquired additional along-track scanning radiometer(ATSR) data for the Arctic and Antarctic now totalling over eight months; (3) refined our AVHRR Arctic and Antarctic ice surface temperature (IST) retrieval algorithm, including work specific to Greenland; (4) developed ATSR retrieval algorithms for the Arctic and Antarctic, including work specific to Greenland; (5) developed cloud masking procedures for both AVHRR and ATSR; (6) generated a two-week bi-polar global area coverage (GAC) set of composite images from which IST is being estimated; (7) investigated the effects of clouds and the atmosphere on passive microwave 'surface' temperature retrieval algorithms; and (8) generated surface temperatures for the Beaufort Sea data set, both from AVHRR and special sensor microwave imager (SSM/I).
Understanding global climate change scenarios through bioclimate stratification
NASA Astrophysics Data System (ADS)
Soteriades, A. D.; Murray-Rust, D.; Trabucco, A.; Metzger, M. J.
2017-08-01
Despite progress in impact modelling, communicating and understanding the implications of climatic change projections is challenging due to inherent complexity and a cascade of uncertainty. In this letter, we present an alternative representation of global climate change projections based on shifts in 125 multivariate strata characterized by relatively homogeneous climate. These strata form climate analogues that help in the interpretation of climate change impacts. A Random Forests classifier was calculated and applied to 63 Coupled Model Intercomparison Project Phase 5 climate scenarios at 5 arcmin resolution. Results demonstrate how shifting bioclimate strata can summarize future environmental changes and form a middle ground, conveniently integrating current knowledge of climate change impact with the interpretation advantages of categorical data but with a level of detail that resembles a continuous surface at global and regional scales. Both the agreement in major change and differences between climate change projections are visually combined, facilitating the interpretation of complex uncertainty. By making the data and the classifier available we provide a climate service that helps facilitate communication and provide new insight into the consequences of climate change.
Geometrically Induced Interactions and Bifurcations
NASA Astrophysics Data System (ADS)
Binder, Bernd
2010-01-01
In order to evaluate the proper boundary conditions in spin dynamics eventually leading to the emergence of natural and artificial solitons providing for strong interactions and potentials with monopole charges, the paper outlines a new concept referring to a curvature-invariant formalism, where superintegrability is given by a special isometric condition. Instead of referring to the spin operators and Casimir/Euler invariants as the generator of rotations, a curvature-invariant description is introduced utilizing a double Gudermann mapping function (generator of sine Gordon solitons and Mercator projection) cross-relating two angular variables, where geometric phases and rotations arise between surfaces of different curvature. Applying this stereographic projection to a superintegrable Hamiltonian can directly map linear oscillators to Kepler/Coulomb potentials and/or monopoles with Pöschl-Teller potentials and vice versa. In this sense a large scale Kepler/Coulomb (gravitational, electro-magnetic) wave dynamics with a hyperbolic metric could be mapped as a geodesic vertex flow to a local oscillator singularity (Dirac monopole) with spherical metrics and vice versa. Attracting fixed points and dynamic constraints are given by special isometries with magic precession angles. The nonlinear angular encoding directly provides for a Shannon mutual information entropy measure of the geodesic phase space flow. The emerging monopole patterns show relations to spiral Fresnel holography and Berry/Aharonov-Bohm geometric phases subject to bifurcation instabilities and singularities from phase ambiguities due to a local (entropy) overload. Neutral solitons and virtual patterns emerging and mediating in the overlap region between charged or twisted holographic patterns are visualized and directly assigned to the Berry geometric phase revealing the role of photons, neutrons, and neutrinos binding repulsive charges in Coulomb, strong and weak interaction.
DOE Office of Scientific and Technical Information (OSTI.GOV)
BEVINS, R.R.
This study is a requirements document that presents analysis for the functional description for the master pump shutdown system. This document identifies the sources of the requirements and/or how these were derived. Each requirement is validated either by quoting the source or an analysis process involving the required functionality, performance characteristics, operations input or engineering judgment. The requirements in this study apply to the first phase of the W314 Project. This document has been updated during the definitive design portion of the first phase of the W314 Project to capture additional software requirements and is planned to be updated duringmore » the second phase of the W314 Project to cover the second phase of the project's scope.« less
X-29 Research Pilot Rogers Smith
NASA Technical Reports Server (NTRS)
1988-01-01
Rogers Smith, a NASA research pilot, is seen here at the cockpit of the X-29 forward-swept-wing technology demonstrator at NASA's Ames-Dryden Flight Research Facility (later the Dryden Flight Research Center), Edwards, California, in 1988. The X-29 explored the use of advanced composites in aircraft construction; variable camber wing surfaces; the unique forward-swept-wing and its thin supercritical airfoil; strake flaps; and a computerized fly-by-wire flight control system that overcame the aircraft's instability. Grumman Aircraft Corporation built two X-29s. They were flight tested at Dryden from 1984 to 1992 in a joint NASA, DARPA (Defense Advanced Research Projects Agency) and U.S. Air Force program. Two X-29 aircraft, featuring one of the most unusual designs in aviation history, flew at the Ames-Dryden Flight Research Facility (now the Dryden Flight Research Center, Edwards, California) from 1984 to 1992. The fighter-sized X-29 technology demonstrators explored several concepts and technologies including: the use of advanced composites in aircraft construction; variable-camber wing surfaces; a unique forward- swept wing and its thin supercritical airfoil; strakes; close-coupled canards; and a computerized fly-by-wire flight control system used to maintain control of the otherwise unstable aircraft. Research results showed that the configuration of forward-swept wings, coupled with movable canards, gave pilots excellent control response at angles of attack of up to 45 degrees. During its flight history, the X-29 aircraft flew 422 research missions and a total of 436 missions. Sixty of the research flights were part of the X-29 follow-on 'vortex control' phase. The forward-swept wing of the X-29 resulted in reverse airflow, toward the fuselage rather than away from it, as occurs on the usual aft-swept wing. Consequently, on the forward-swept wing, the ailerons remained unstalled at high angles of attack. This provided better airflow over the ailerons and prevented stalling (loss of lift) at high angles of attack. Introduction of composite materials in the 1970s opened a new field of aircraft construction. It also made possible the construction of the X-29's thin supercritical wing. State-of-the-art composites allowed aeroelastic tailoring which, in turn, allowed the wing some bending but limited twisting and eliminated structural divergence within the flight envelope (i.e. deformation of the wing or the wing breaking off in flight). Additionally, composite materials allowed the wing to be sufficiently rigid for safe flight without adding an unacceptable weight penalty. The X-29 project consisted of two phases plus the follow-on vortex-control phase. Phase 1 demonstrated that the forward sweep of the X-29 wings kept the wing tips unstalled at the moderate angles of attack flown in that phase (a maximum of 21 degrees). Phase I also demonstrated that the aeroelastic tailored wing prevented structural divergence of the wing within the flight envelope, and that the control laws and control-surface effectiveness were adequate to provide artificial stability for an otherwise unstable aircraft. Phase 1 further demonstrated that the X-29 configuration could fly safely and reliably, even in tight turns. During Phase 2 of the project, the X-29, flying at an angle of attack of up to 67 degrees, demonstrated much better control and maneuvering qualities than computational methods and simulation models had predicted . During 120 research flights in this phase, NASA, Air Force, and Grumman project pilots reported the X-29 aircraft had excellent control response to an angle of attack of 45 degrees and still had limited controllability at a 67-degree angle of attack. This controllability at high angles of attack can be attributed to the aircraft's unique forward-swept wing- canard design. The NASA/Air Force-designed high-gain flight control laws also contributed to the good flying qualities. During the Air Force-initiated vortex-control phase, the X-29 successfully demonstrated vortex flow control (VFC). This VFC was more effective than expected in generating yaw forces, especially in high angles of attack where the rudder is less effective. VFC was less effective in providing control when sideslip (wind pushing on the side of the aircraft) was present, and it did little to decrease rocking oscillation of the aircraft. The X-29 vehicle was a single-engine aircraft, 48.1 feet long with a wing span of 27.2 feet. Each aircraft was powered by a General Electric F404-GE-400 engine producing 16,000 pounds of thrust. The program was a joint effort of the Department of Defense's Defense Advanced Research Projects Agency (DARPA), the U.S. Air Force, the Ames-Dryden Flight Research Facility, the Air Force Flight Test Center, and the Grumman Corporation. The program was managed by the Air Force's Wright Laboratory, Wright Patterson Air Force Base, Ohio.
Aerosol-cloud interactions in Arctic mixed-phase stratocumulus
NASA Astrophysics Data System (ADS)
Solomon, A.
2017-12-01
Reliable climate projections require realistic simulations of Arctic cloud feedbacks. Of particular importance is accurately simulating Arctic mixed-phase stratocumuli (AMPS), which are ubiquitous and play an important role in regional climate due to their impact on the surface energy budget and atmospheric boundary layer structure through cloud-driven turbulence, radiative forcing, and precipitation. AMPS are challenging to model due to uncertainties in ice microphysical processes that determine phase partitioning between ice and radiatively important cloud liquid water. Since temperatures in AMPS are too warm for homogenous ice nucleation, ice must form through heterogeneous nucleation. In this presentation we discuss a relatively unexplored source of ice production-recycling of ice nuclei in regions of ice subsaturation. AMPS frequently have ice-subsaturated air near the cloud-driven mixed-layer base where falling ice crystals can sublimate, leaving behind IN. This study provides an idealized framework to understand feedbacks between dynamics and microphysics that maintain phase-partitioning in AMPS. In addition, the results of this study provide insight into the mechanisms and feedbacks that may maintain cloud ice in AMPS even when entrainment of IN at the mixed-layer boundaries is weak.
An enhanced archive facilitating climate impacts analysis
Maurer, E.P.; Brekke, L.; Pruitt, T.; Thrasher, B.; Long, J.; Duffy, P.; Dettinger, M.; Cayan, D.; Arnold, J.
2014-01-01
We describe the expansion of a publicly available archive of downscaled climate and hydrology projections for the United States. Those studying or planning to adapt to future climate impacts demand downscaled climate model output for local or regional use. The archive we describe attempts to fulfill this need by providing data in several formats, selectable to meet user needs. Our archive has served as a resource for climate impacts modelers, water managers, educators, and others. Over 1,400 individuals have transferred more than 50 TB of data from the archive. In response to user demands, the archive has expanded from monthly downscaled data to include daily data to facilitate investigations of phenomena sensitive to daily to monthly temperature and precipitation, including extremes in these quantities. New developments include downscaled output from the new Coupled Model Intercomparison Project phase 5 (CMIP5) climate model simulations at both the monthly and daily time scales, as well as simulations of surface hydrologi- cal variables. The web interface allows the extraction of individual projections or ensemble statistics for user-defined regions, promoting the rapid assessment of model consensus and uncertainty for future projections of precipitation, temperature, and hydrology. The archive is accessible online (http://gdo-dcp.ucllnl.org/downscaled_ cmip_projections).
ANALYTICAL CHEMISTRY RESEARCH NEEDS FOR ...
The consensus among environmental scientists and risk assessors is that the fate and effects of pharmaceutical and personal care products (PPCPS) in the environment are poorly understood. Many classes of PPCPs have yet to be investigated. Acquisition of trends data for a suite of PPCPs (representatives from each of numerous significant classes), shown to recur amongst municipal wastewater treatment plants across the country, may prove of key importance. The focus of this paper is an overview of some of the analytical methods being developed at the Environmenental Protection Agency and their application to wastewater and surface water samples. Because PPCPs are generally micro-pollutants, emphasis is on development of enrichment and pre- concentration techniques using various means of solid-phase extraction. The research focused on in the subtasks is the development and application of state-of the-art technologies to meet the needs of the public, Office of Water, and ORD in the area of Water Quality. Located In the subtasks are the various research projects being performed in support of this Task and more in-depth coverage of each project. Briefly, each project's objective is stated below.Subtask 1: To integrate state-of-the-art technologies (polar organic chemical integrative samplers, advanced solid-phase extraction methodologies with liquid chromatography/electrospray/mass spectrometry) and apply them to studying the sources and fate of a select list of PPCP
ERIC Educational Resources Information Center
Hannah, Kathryn
Since August of 1976, the Faculty of Nursing at the University of Calgary has developed and implemented a four-phase computer assisted instruction (CAI) project. In Phase I, the pilot project to demonstrate effectiveness of CAI as an alternative teaching strategy in that setting has been completed and replication is on-going. In Phase II,…
Carbon Capture and Sequestration from a Hydrogen Production Facility in an Oil Refinery
DOE Office of Scientific and Technical Information (OSTI.GOV)
Engels, Cheryl; Williams, Bryan, Valluri, Kiranmal; Watwe, Ramchandra
2010-06-21
The project proposed a commercial demonstration of advanced technologies that would capture and sequester CO2 emissions from an existing hydrogen production facility in an oil refinery into underground formations in combination with Enhanced Oil Recovery (EOR). The project is led by Praxair, Inc., with other project participants: BP Products North America Inc., Denbury Onshore, LLC (Denbury), and Gulf Coast Carbon Center (GCCC) at the Bureau of Economic Geology of The University of Texas at Austin. The project is located at the BP Refinery at Texas City, Texas. Praxair owns and operates a large hydrogen production facility within the refinery. Asmore » part of the project, Praxair would construct a CO2 capture and compression facility. The project aimed at demonstrating a novel vacuum pressure swing adsorption (VPSA) based technology to remove CO2 from the Steam Methane Reformers (SMR) process gas. The captured CO2 would be purified using refrigerated partial condensation separation (i.e., cold box). Denbury would purchase the CO2 from the project and inject the CO2 as part of its independent commercial EOR projects. The Gulf Coast Carbon Center at the Bureau of Economic Geology, a unit of University of Texas at Austin, would manage the research monitoring, verification and accounting (MVA) project for the sequestered CO2, in conjunction with Denbury. The sequestration and associated MVA activities would be carried out in the Hastings field at Brazoria County, TX. The project would exceed DOE?s target of capturing one million tons of CO2 per year (MTPY) by 2015. Phase 1 of the project (Project Definition) is being completed. The key objective of Phase 1 is to define the project in sufficient detail to enable an economic decision with regard to proceeding with Phase 2. This topical report summarizes the administrative, programmatic and technical accomplishments completed in Phase 1 of the project. It describes the work relative to project technical and design activities (associated with CO2 capture technologies and geologic sequestration MVA), and Environmental Information Volume. Specific accomplishments of this Phase include: 1. Finalization of the Project Management Plan 2. Development of engineering designs in sufficient detail for defining project performance and costs 3. Preparation of Environmental Information Volume 4. Completion of Hazard Identification Studies 5. Completion of control cost estimates and preparation of business plan During the Phase 1 detailed cost estimate, project costs increased substantially from the previous estimate. Furthermore, the detailed risk assessment identified integration risks associated with potentially impacting the steam methane reformer operation. While the Phase 1 work identified ways to mitigate these integration risks satisfactorily from an operational perspective, the associated costs and potential schedule impacts contributed to the decision not to proceed to Phase 2. We have concluded that the project costs and integration risks at Texas City are not commensurate with the potential benefits of the project at this time.« less
Quantification of the Mass Transfer at Fluid Interfaces in Microfluidic Channels
NASA Astrophysics Data System (ADS)
Wismeth, Carina; Manhart, Michael; Niessner, Reinhard; Baumann, Thomas
2017-04-01
Mass transfer rates at interfaces in a complex porous media are relevant in many environmental applications and control the functions of natural filter systems in subsurface environments. The mass transfer at fluid interfaces is associated with interface convection caused by local inhomogeneities in interface tension and hydrodynamic instabilities at the interface. If there is a surface tension gradient along the surface a shear stress jump is generated that results in fluid motion along the surface that is called Marangoni effect. These spontaneous convection currents can lead to an increased mass transfer of the transition component at the phase boundary and to an increased mixing of the phases. Therefore compensatory currents at the interface can have a significant influence on the subsurface transport of contaminants in the groundwater area, especially in the vadose zone. Using microfluidic channels and advanced experimental techniques it is possible to measure the fluid flow and mass transfer rates directly and to quantify the effect of the Marangoni convection on the mass transfer at interfaces between a non-aqueous liquid and water with high temporal and spatial resolution. The use of fluorescent particles as well as the recording and analysis of their trajectories is intended to visualize interfacial processes and to quantify the mass transfer at fluid phase boundaries. Concentration gradients at the interface are analysed by spectroscopic methods and allow an assessment of the enrichment and depletion at the phase boundaries. Extensive test series provide the experimental basis for quantifying and analysing the impact of the Marangoni effect on the mass transfer rates at interfaces in porous media in subsurface aquatic environments. Within this research project we concentrate on the effect of Marangoni convection on the mass transfer near an 1-octanol-water interface, which serves as a well defined proxy for non-aqueous phase liquids in porous media. Experiments and a numerical simulation are closely coupled to provide a generic data set with high reproducibility and used to obtain highly resolved three-dimensional data of mass transfer in two- and three-phase systems to foster the understanding of subsurface transport, especially in the vadose zone.
Chattanooga SmartBus Project : phase III evaluation report
DOT National Transportation Integrated Search
2009-12-01
This report presents the results of Phase III of the national evaluation of the Chattanooga Area Regional Transportation Authoritys (CARTA) SmartBus Project. The SmartBus Project is a comprehensive transit ITS program for the city of Chattanooga, ...
DOT National Transportation Integrated Search
2015-01-01
As mobile technology becomes widely available and affordable, transportation agencies can use this : technology to streamline operations involved within project inspection. This research, conducted in two : phases, identified opportunities for proces...
30 CFR 881.6 - Project contract.
Code of Federal Regulations, 2011 CFR
2011-07-01
..., if the work is to be done in phases, a series of project contracts, entered into by the State and its... phase of a project, is limited to the estimated costs established in the cooperative agreement. If the... representative present. (d) If the State amends a project contract, or issues a change order thereunder, and the...
DOT National Transportation Integrated Search
1997-01-01
The purpose of this Phase 2 Study is to compare national motor vehicle accident projections : made from the Crash Avoidance Research Data base (CARDfile) with national motor : vehicle accident projections made from other data bases. For the most part...
Allan, Andrea M.; Hostetler, Steven W.; Alder, Jay R.
2014-01-01
We use the NCEP/NCAR Reanalysis (NCEP) and the MPI/ECHAM5 general circulation model to drive the RegCM3 regional climate model to assess the ability of the models to reproduce the spatiotemporal aspects of the Pacific-North American teleconnection (PNA) pattern. Composite anomalies of the NCEP-driven RegCM3 simulations for 1982–2000 indicate that the regional model is capable of accurately simulating the key features (500-hPa heights, surface temperature, and precipitation) of the positive and negative phases of the PNA with little loss of information in the downscaling process. The basic structure of the PNA is captured in both the ECHAM5 global and ECHAM5-driven RegCM3 simulations. The 1950–2000 ECHAM5 simulation displays similar temporal and spatial variability in the PNA index as that of NCEP; however, the magnitudes of the positive and negative phases are weaker than those of NCEP. The RegCM3 simulations clearly differentiate the climatology and associated anomalies of snow water equivalent and soil moisture of the positive and negative PNA phases. In the RegCM3 simulations of the future (2050–2100), changes in the location and extent of the Aleutian low and the continental high over North America alter the dominant flow patterns associated with positive and negative PNA modes. The future projections display a shift in the patterns of the relationship between the PNA and surface climate variables, which suggest the potential for changes in the PNA-related surface hydrology of North America.
Rayleigh wave phase velocity maps from the ambient noise tomography in central Mongolia
NASA Astrophysics Data System (ADS)
Pan, J.; Wu, Q.; Gao, M.; Li, Y.; Demberel, S. G.; Munkhuu, U.
2013-12-01
The study area (103°E-111°E, 44°N-49°N) located in the Mongolian fold belts and situated at the southeast of Baikal rift zone which is known as one of the most active regions on the Earth due to integrated influence of the India-Asia collision and compression and the subduction of the Pacific Plate. Additionally, it also located in the north of South-North earthquake belts of China. So, it is believed to be an ideal site for understanding intraplate dynamics. Seismic ambient noise tomography has been performed all over the world these years, and it has been proved it's a powerful way to image and study the structure of crust and uppermost mantle due to its exclusive capability to extract estimated Green's functions for short period surface waves. Compared with traditional earthquake tomography methods of surface waves, ambient noise tomography hasn't limitations related to the distribution of earthquakes as well as errors in earthquake locations and source mechanisms. A new scientific project was carried out in 2011 by Institute of Geophysics of China Earthquake Administration (IGP-CEA) and Research center of Astronomy and Geophysics of Mongolian Academy of Science (RCAG-MAS). In the seismic sub-project 60 portable seismic stations were deployed in central Mongolia in August 2011. Continuous time-series of vertical component between August 2011 and July 2012 have been collected and cross-correlated to obtain estimated Green's functions (EGF) of Rayleigh wave. Using the frequency and time analysis technique based on continuous wavelet transformation, 1258 of phase velocity dispersion curves of Rayleigh wave were extracted from EGFs. High resolution phase velocity maps at periods of 5, 10, 20 and 30 s were reconstructed with grid size 0.5°x0.5° by utilizing a generalized 2-D-linear inversion method developed by Ditmar & Yanovskaya. The tomography results reveal lateral heterogeneity of shear wave structure in the crust and upper mantle in the study region. For periods shorter than 10 s, the phase velocity variations are well correlated with the principal geological units, with low-speed anomalies corresponding to the sedimentary basins and high-speed anomalies coinciding with the main mountain ranges. Within the period range from 20 s to 30 s, phase velocity distribution is correlated to the crust thickness. However, the value of phase velocities have little lateral changes with ~0.15km/s on each map for the whole period band ranging from 5 s to 30 s, indicating that it doesn't have big lateral heterogeneity for shear wave structure in the crust and upper mantle in the study region.This study was supported by the international cooperation project of the Ministry of Science and Technology of China (2011DFB20120) and NSFC (41104029)
ART/Ada design project, phase 1: Project plan
NASA Technical Reports Server (NTRS)
Allen, Bradley P.
1988-01-01
The plan and schedule for Phase 1 of the Ada based ESBT Design Research Project is described. The main platform for the project is a DEC Ada compiler on VAX mini-computers and VAXstations running the Virtual Memory System (VMS) operating system. The Ada effort and lines of code are given in tabular form. A chart is given of the entire project life cycle.
NASA Technical Reports Server (NTRS)
Uslenghi, Piergiorgio L. E.; Laxpati, Sharad R.; Kawalko, Stephen F.
1993-01-01
The third phase of the development of the computer codes for scattering by coated bodies that has been part of an ongoing effort in the Electromagnetics Laboratory of the Electrical Engineering and Computer Science Department at the University of Illinois at Chicago is described. The work reported discusses the analytical and numerical results for the scattering of an obliquely incident plane wave by impedance bodies of revolution with phi variation of the surface impedance. Integral equation formulation of the problem is considered. All three types of integral equations, electric field, magnetic field, and combined field, are considered. These equations are solved numerically via the method of moments with parametric elements. Both TE and TM polarization of the incident plane wave are considered. The surface impedance is allowed to vary along both the profile of the scatterer and in the phi direction. Computer code developed for this purpose determines the electric surface current as well as the bistatic radar cross section. The results obtained with this code were validated by comparing the results with available results for specific scatterers such as the perfectly conducting sphere. Results for the cone-sphere and cone-cylinder-sphere for the case of an axially incident plane were validated by comparing the results with the results with those obtained in the first phase of this project. Results for body of revolution scatterers with an abrupt change in the surface impedance along both the profile of the scatterer and the phi direction are presented.
A Sample Handling System for Mars Sample Return - Design and Status
NASA Astrophysics Data System (ADS)
Allouis, E.; Renouf, I.; Deridder, M.; Vrancken, D.; Gelmi, R.; Re, E.
2009-04-01
A mission to return atmosphere and soil samples form the Mars is highly desired by planetary scientists from around the world and space agencies are starting preparation for the launch of a sample return mission in the 2020 timeframe. Such a mission would return approximately 500 grams of atmosphere, rock and soil samples to Earth by 2025. Development of a wide range of new technology will be critical to the successful implementation of such a challenging mission. Technical developments required to realise the mission include guided atmospheric entry, soft landing, sample handling robotics, biological sealing, Mars atmospheric ascent sample rendezvous & capture and Earth return. The European Space Agency has been performing system definition studies along with numerous technology development studies under the framework of the Aurora programme. Within the scope of these activities Astrium has been responsible for defining an overall sample handling architecture in collaboration with European partners (sample acquisition and sample capture, Galileo Avionica; sample containment and automated bio-sealing, Verhaert). Our work has focused on the definition and development of the robotic systems required to move the sample through the transfer chain. This paper presents the Astrium team's high level design for the surface transfer system and the orbiter transfer system. The surface transfer system is envisaged to use two robotic arms of different sizes to allow flexible operations and to enable sample transfer over relatively large distances (~2 to 3 metres): The first to deploy/retract the Drill Assembly used for sample collection, the second for the transfer of the Sample Container (the vessel containing all the collected samples) from the Drill Assembly to the Mars Ascent Vehicle (MAV). The sample transfer actuator also features a complex end-effector for handling the Sample Container. The orbiter transfer system will transfer the Sample Container from the capture mechanism through a bio-sealing system to the Earth Return Capsule (ERC) and has distinctly different requirements from the surface transfer system. The operations required to transfer the samples to the ERC are clearly defined and make use of mechanisms specifically designed for the job rather than robotic arms. Though it is mechanical rather than robotic, the design of the orbiter transfer system is very complex in comparison to most previous missions to fulfil all the scientific and technological requirements. Further mechanisms will be required to lock the samples into the ERC and to close the door at the rear of the ERC through which the samples have been inserted. Having performed this overall definition study, Astrium is now leading the next step of the development of the MSR sample handling: the Mars Surface Sample Transfer and Manipulation project (MSSTM). Organised in two phases, the project will re-evaluate in phase 1 the output of the previous study in the light of new inputs (e.g. addition of a rover) and investigate further the architectures and systems involved in the sample transfer chain while identifying the critical technologies. The second phase of the project will concentrate on the prototyping of a number of these key technologies with the goal of providing an end-to end validation of the surface sample transfer concept.
Space-Based Telemetry and Range Safety Project Ku-Band and Ka-Band Phased Array Antenna
NASA Technical Reports Server (NTRS)
Whiteman, Donald E.; Valencia, Lisa M.; Birr, Richard B.
2005-01-01
The National Aeronautics and Space Administration Space-Based Telemetry and Range Safety study is a multiphase project to increase data rates and flexibility and decrease costs by using space-based communications assets for telemetry during launches and landings. Phase 1 used standard S-band antennas with the Tracking and Data Relay Satellite System to obtain a baseline performance. The selection process and available resources for Phase 2 resulted in a Ku-band phased array antenna system. Several development efforts are under way for a Ka-band phased array antenna system for Phase 3. Each phase includes test flights to demonstrate performance and capabilities. Successful completion of this project will result in a set of communications requirements for the next generation of launch vehicles.
Ku- and Ka-Band Phased Array Antenna for the Space-Based Telemetry and Range Safety Project
NASA Technical Reports Server (NTRS)
Whiteman, Donald E.; Valencia, Lisa M.; Birr, Richard B.
2005-01-01
The National Aeronautics and Space Administration Space-Based Telemetry and Range Safety study is a multiphase project to increase data rates and flexibility and decrease costs by using space-based communications assets for telemetry during launches and landings. Phase 1 used standard S-band antennas with the Tracking and Data Relay Satellite System to obtain a baseline performance. The selection process and available resources for Phase 2 resulted in a Ku-band phased array antenna system. Several development efforts are under way for a Ka-band phased array antenna system for Phase 3. Each phase includes test flights to demonstrate performance and capabilities. Successful completion of this project will result in a set of communications requirements for the next generation of launch vehicles.
Electronic construction collaboration system -- final phase.
DOT National Transportation Integrated Search
2014-09-01
This phase of the research project involved two major efforts: (1) Complete the implementation of AEC-Sync (formerly known as : Attolist) on the Iowa Falls Arch Bridge project and (2) develop a WPMS for projects under $10 million. : For the first maj...
NASA Astrophysics Data System (ADS)
Ghyngazov, S. A.; Vasiliev, I. P.; Frangulyan, T. S.; Chernyavski, A. V.
2015-10-01
The effect of ion treatment on the phase composition and mechanical properties of the near-surface layers of zirconium ceramic composition 97 ZrO2-3Y2O3 (mol%) was studied. Irradiation of the samples was carried out by accelerated ions of aluminum with using vacuum-arc source Mevva 5-Ru. Ion beam had the following parameters: the energy of the accelerated ions E = 78 keV, the pulse current density Ji = 4mA / cm2, current pulse duration equal τ = 250 mcs, pulse repetition frequency f = 5 Hz. Exposure doses (fluence) were 1016 и 1017 ion/cm2. The depth distribution implanted ions was studied by SIMS method. It is shown that the maximum projected range of the implanted ions is equal to 250 nm. Near-surface layers were investigated by X-ray diffraction (XRD) at fixed glancing incidence angle. It is shown that implantation of aluminum ions into the ceramics does not lead to a change in the phase composition of the near-surface layer. The influence of implanted ions on mechanical properties of ceramic near-surface layers was studied by the method of dynamic nanoindentation using small loads on the indenter P=300 mN. It is shown that in ion- implanted ceramic layer the processes of material recovery in the deformed region in the unloading mode proceeds with higher efficiency as compared with the initial material state. The deformation characteristics of samples before and after ion treatment have been determined from interpretation of the resulting P-h curves within the loading and unloading sections by the technique proposed by Oliver and Pharr. It was found that implantation of aluminum ions in the near-surface layer of zirconia ceramics increases nanohardness and reduces the Young's modulus.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mllett, Paul; McDeavitt, Sean; Deo, Chaitanya
This proposal will investigate the stability of bimodal pore size distributions in metallic uranium and uranium-zirconium alloys during sintering and re-sintering annealing treatments. The project will utilize both computational and experimental approaches. The computational approach includes both Molecular Dynamics simulations to determine the self-diffusion coefficients in pure U and U-Zr alloys in single crystals, grain boundaries, and free surfaces, as well as calculations of grain boundary and free surface interfacial energies. Phase-field simulations using MOOSE will be conducted to study pore and grain structure evolution in microstructures with bimodal pore size distributions. Experiments will also be performed to validate themore » simulations, and measure the time-dependent densification of bimodal porous compacts.« less
Dai, Meiling; Yang, Fujun; He, Xiaoyuan
2012-04-20
A simple but effective fringe projection profilometry is proposed to measure 3D shape by using one snapshot color sinusoidal fringe pattern. One color fringe pattern encoded with a sinusoidal fringe (as red component) and one uniform intensity pattern (as blue component) is projected by a digital video projector, and the deformed fringe pattern is recorded by a color CCD camera. The captured color fringe pattern is separated into its RGB components and division operation is applied to red and blue channels to reduce the variable reflection intensity. Shape information of the tested object is decoded by applying an arcsine algorithm on the normalized fringe pattern with subpixel resolution. In the case of fringe discontinuities caused by height steps, or spatially isolated surfaces, the separated blue component is binarized and used for correcting the phase demodulation. A simple and robust method is also introduced to compensate for nonlinear intensity response of the digital video projector. The experimental results demonstrate the validity of the proposed method.
Monterey-Salinas Transit ITS Augmentation Project : Phase III Evaluation Report
DOT National Transportation Integrated Search
2009-12-01
The purpose of this document is to present the findings from Phase II and Phase III of the Evaluation of the Intelligent Transportation Systems (ITS) Augmentation Project that was implemented at the Monterey-Salinas Transit (MST) in Monterey, Califor...
WVU Hydrogen Fuel Dispensing Station
DOE Office of Scientific and Technical Information (OSTI.GOV)
Davis, William
2015-09-01
The scope of this project was changed during the course of the project. Phase I of the project was to construct a site similar to the site at Central West Virginia Regional Airport in Charleston, WV to show that duplication of the site was a feasible method of conducting hydrogen stations. Phase II of the project was necessitated due to a lack of funding that was planned for the development of the station in Morgantown. The US Department of Energy determined that the station in Charleston would be dismantled and moved to Morgantown and reassembled at the Morgantown site. Thismore » necessitated storage of the components of the station for almost a year at the NAFTC Headquarters which caused a number of issues with the equipment that will be discussed in later portions of this report. This report will consist of PHASE I and PHASE II with discussions on each of the tasks scheduled for each phase of the project.« less
NASA Astrophysics Data System (ADS)
Saputra, Y. A.; Setyaningtyas, V. E. D.; Latiffianti, E.; Wijaya, S. H.; Ladamay, O. S. A.
2018-04-01
Measuring project success level is a challenging activity. This area of works has attracted many researchers to look deeper into the method of measurement, success factor identification, risk management, and many others relevant topics. However, the project management scope is limited until the project handover stage. After a project handover, the control of a project management changes from Project Management Team to the project owner/commercialization team. From an investor’s point of view, the success of a project delivery needs to be followed by the success of commercialization phase. This paper aims to present an approach on how we track and measure the progress and success level of a project investment in the commercialization phase. This is an interesting topic which probably often being forgotten in many practical case. Our proposed concept modify Freeman and Beale concept by estimating the variance between the Planned Net Present Value / Annual Worth (as it is in the Feasibility Study Document) and the Actual Net Present Value / Annual Worth (until the point time of evaluation). The gap will lead us to the next analysis and give us some important information, especially exposing whether our project investment performs better than the planning or underperformed. Some corrective actions can be suggested based on the provided information. Practical cases to exercise the concept is also provided and discussed; one case in a property sector in the middle of commercialization phase, and another case in a Power Plant investment approaching the end of commercialization phase.
NASA Astrophysics Data System (ADS)
Fernandes, Katia; Giannini, Alessandra; Verchot, Louis; Baethgen, Walter; Pinedo-Vasquez, Miguel
2015-08-01
The unusual severity and return time of the 2005 and 2010 dry-season droughts in western Amazon is attributed partly to decadal climate fluctuations and a modest drying trend. Decadal variability of western Amazon hydroclimate is highly correlated to the Atlantic sea surface temperature (SST) north-south gradient (NSG). Shifts of dry and wet events frequencies are also related to the NSG phase, with a 66% chance of 3+ years of dry events per decade when NSG > 0 and 19% when NSG < 0. The western Amazon and NSG decadal covariability is well reproduced in general circulation models (GCMs) historical (HIST) and preindustrial control (PIC) experiments of the Coupled Model Intercomparison Project Phase 5 (CMIP5). The HIST and PIC also reproduce the shifts in dry and wet events probabilities, indicating potential for decadal predictability based on GCMs. Persistence of the current NSG positive phase favors above normal frequency of western Amazon dry events in coming decades.
NASA Astrophysics Data System (ADS)
Chisholm, John
2013-10-01
Galactic outflows have become vital for understanding galaxy evolution. Outflows have been used to explain the mass-metallicity relation, the star formation history of the universe, and the shape of the baryonic mass function. However, few studies have focused on the basic question of how outflow velocities depend upon the physical properties of their host galaxies. Here we propose an archival project utilizing 52 COS spectra of local star-forming galaxies spanning four decades of star formation rate, and stellar mass. We will preform a self-consistent analysis of trends between galactic properties {star formation rate, stellar mass, specific star formation rate and star formation rate surface density} and outflow velocities measured from interstellar metal absorption lines {e.g., CII 1335}. We will extend this analysis to different gas phases - cold, warm, and hot - to gain a more comprehensive understanding of the physics of multi-phase outflows. The trends we observe will provide insights into the feedback process and will be crucial new benchmarks for simulations.
NASA Astrophysics Data System (ADS)
Nakamura, Hiroo; Riccardi, B.; Loginov, N.; Ara, K.; Burgazzi, L.; Cevolani, S.; Dell'Orco, G.; Fazio, C.; Giusti, D.; Horiike, H.; Ida, M.; Ise, H.; Kakui, H.; Matsui, H.; Micciche, G.; Muroga, T.; Nakamura, Hideo; Shimizu, K.; Sugimoto, M.; Suzuki, A.; Takeuchi, H.; Tanaka, S.; Yoneoka, T.
2004-08-01
During the three year key element technology phase of the International Fusion Materials Irradiation Facility (IFMIF) project, completed at the end of 2002, key technologies have been validated. In this paper, these results are summarized. A water jet experiment simulating Li flow validated stable flow up to 20 m/s with a double reducer nozzle. In addition, a small Li loop experiment validated stable Li flow up to 14 m/s. To control the nitrogen content in Li below 10 wppm will require surface area of a V-Ti alloy getter of 135 m 2. Conceptual designs of diagnostics have been carried out. Moreover, the concept of a remote handling system to replace the back wall based on `cut and reweld' and `bayonet' options has been established. Analysis by FMEA showed safe operation of the target system. Recent activities in the transition phase, started in 2003, and plan for the next phase are also described.
NASA Astrophysics Data System (ADS)
Lu, Xiaolong; Shi, Ruixin; Hao, Changchun; Chen, Huan; Zhang, Lei; Li, Junhua; Xu, Guoqing; Sun, Runguang
2016-09-01
The interaction between proteins and lipids is one of the basic problems of modern biochemistry and biophysics. The purpose of this study is to compare the penetration degree of lysozyme into 1,2-diapalmitoyl-sn-glycero-3-phosphocholine (DPPC) and 1,2-dipalmitoyl-sn-glycero-3-phosphoethano-lamine (DPPE) by analyzing the data of surface pressure-area (π-A) isotherms and surface pressure-time (π-T) curves. Lysozyme can penetrate into both DPPC and DPPE monolayers because of the increase of surface pressure at an initial pressure of 15 mN/m. However, the changes of DPPE are larger than DPPC, indicating stronger interaction of lysozyme with DPPE than DPPC. The reason may be due to the different head groups and phase state of DPPC and DPPE monolayers at the surface pressure of 15 mN/m. Atomic force microscopy reveals that lysozyme was absorbed by DPPC and DPPE monolayers, which leads to self-aggregation and self-assembly, forming irregular multimers and conical multimeric. Through analysis, we think that the process of polymer formation is similar to the aggregation mechanism of amyloid fibers. Project supported by the National Natural Science Foundation of China (Grant Nos. 21402114 and 11544009), the Natural Science Basic Research Plan in Shaanxi Province of China (Grant No. 2016JM2010), the Fundamental Research Funds for the Central Universities of China (Grant No. GK201603026), and the National University Science and Technology Innovation Project of China (Grant No. 201610718013).
Optical aperture synthesis: limitations and interest for the earth observation
NASA Astrophysics Data System (ADS)
Brouard, Laurent; Safa, Frederic; Crombez, Vincent; Laubier, David
2017-11-01
For very large telescope diameters, typically above 4 meters, monolithic telescopes can hardly be envisaged for space applications. Optical aperture synthesis can be envisaged in the future for improving the image resolution from high altitude orbits by co-phasing several individual telescopes of smaller size and reconstituting an aperture of large surface. The telescopes can be deployed on a single spacecraft or distributed on several spacecrafts in free flying formation. Several future projects are based on optical aperture synthesis for science or earth observation. This paper specifically discusses the limitations and interest of aperture synthesis technique for Earth observation from high altitude orbits, in particular geostationary orbit. Classical Fizeau and Michelson configurations are recalled, and system design aspects are investigated: synthesis of the Modulation Transfer Function (MTF), integration time and imaging procedure are first discussed then co-phasing strategies and instrument metrology are developed. The discussion is supported by specific designs made at EADS Astrium. As example, a telescope design is presented with a surface of only 6.6 m2 for the primary mirror for an external diameter of 10.6 m allowing a theoretical resolution of 1.2 m from geostationary orbit with a surface lower than 10% of the overall surface. The impact is that the integration time is increasing leading to stringent satellite attitude requirements. Image simulation results are presented. The practical implementation of the concept is evaluated in terms of system impacts in particular spacecraft attitude control, spacecraft operations and imaging capability limitations.
Project K.I.C.K., A School-Based Drug Education Research Project--Peers, Parents and Kids.
ERIC Educational Resources Information Center
Rollin, Stephen A.; And Others
1994-01-01
Evaluated first phase of three-phase research project, Project KICK (Kids in Cooperation with Kids) by examining interaction between parent education, positive peer role modeling, and drug education for third graders. Hypothesized that intervention would lead to increase in self-esteem, improved attitudes, increased knowledge regarding drugs, and…
Iowa High School Industrial Arts Curriculum Project. Report on Year One of Phase II.
ERIC Educational Resources Information Center
Des Moines Public Schools, IA.
Phase II of the Iowa High School Industrial Arts project sought to revise industrial arts content to include the infusion of new technologies, structured mathematics and science content, and a less project-oriented approach to teaching. The project identified a philosophical basis and a content structure; set priorities for development and…
NHEXAS PHASE I MARYLAND STUDY--QUALITY SYSTEMS AND IMPLEMENTATION PLAN (HSPH QSIP)
This document describes the project design and quality systems used by the Maryland Study for NHEXAS Phase 1. It contains the following sections: Project Planning and Organization, Project Implementation Plan, Data Acquisition and Management, Records Usage and Management, Routin...
Development of a highway incident management operational and training guide : phase II.
DOT National Transportation Integrated Search
2014-08-01
The overall goal of both phases of this project was to reduce responder fatalities and injuries, as well as to prevent : secondary crashes, especially those involving incident responders. The phases of this project worked toward this goal : by creati...
This report summarizes Phase II (site optimization) of the Nationwide Fund-lead Pump and Treat Optimization Project. This phase included conducting Remediation System Evaluations (RSEs) at each of the 20 sites selected in Phase I.
SmartPark Technology Demonstration Project, Phase II: Final Report
DOT National Transportation Integrated Search
2018-05-01
The purpose of FMCSA's SmartPark project was to determine the feasibility of a technology for providing truck parking space availability information in real time to truckers on the road. SmartPark consisted of two phases. Phase I was a field operatio...
PUBLIC HEALTH AIR SURVEILLANCE EVALUATION (PHASE): BACKGROUND AND AIR QUALITY ASPECT
NERL's Human Exposure and Atmospheric Sciences Division and other participants in the Public Health Air Surveillance Evaluation (PHASE) project will be discussing their results with the New York State Departments of Health and Environmental Conservation. The PHASE project is a ...
Tennessee DUI probation followup demonstration project
DOT National Transportation Integrated Search
1981-04-01
This project was funded in 1975 for a 1 year planning phase, a 2 year operational phase, and a 221 year follow up period. During the operational phase, 4,148 clients were classified by drinker type using Mortimer-Filkins, and randomly assigned to tre...
DESIGN OF A TRAP GREASE UPGRADER FOR BIOFUEL PROCESSING - PHASE I
This project provides capstone senior design experience to several teams of engineering undergraduates at Drexel University through the technical and economic evaluation of a trap grease to biodiesel conversion process. The project incorporates two phases: Phase I characteri...
MERTIS: the thermal infrared imaging spectrometer onboard of the Mercury Planetary Orbiter
NASA Astrophysics Data System (ADS)
Zeh, T.; Peter, G.; Walter, I.; Kopp, E.; Knollenberg, J.; Helbert, J.; Gebhardt, A.; Weber, I.; Hiesinger, Harry
2017-11-01
The MERTIS instrument is a thermal infrared imaging spectrometer onboard of ESA's cornerstone mission BepiColombo to Mercury. MERTIS has four goals: the study of Mercury's surface composition, identification of rock-forming minerals, mapping of the surface mineralogy, and the study of the surface temperature variations and thermal inertia. MERTIS will provide detailed information about the mineralogical composition of Mercury's surface layer by measuring the spectral emittance in the spectral range from 7-14 μm at high spatial and spectral resolution. Furthermore MERTIS will obtain radiometric measurements in the spectral range from 7-40 μm to study the thermo-physical properties of the surface material. The MERTIS detector is based on an uncooled micro-bolometer array providing spectral separation and spatial resolution according to its 2-dimensional shape. The operation principle is characterized by intermediate scanning of the planet surface and three different calibration targets - free space view and two on-board black body sources. In the current project phase, the MERTIS Qualification Model (QM) is under a rigorous testing program. Besides a general overview of the instrument principles, the papers addresses major aspects of the instrument design, manufacturing and verification.
Surface nanocrystalline and hardening effects of Ti-Al-V alloy by electropulsing ultrasonic shock
NASA Astrophysics Data System (ADS)
Ye, Xiaoxin; Tang, Guoyi
2015-03-01
The effect of electropulsing ultrasonic shock (EUS) on the surface hardening and microstructure of Ti6Al4V alloy was studied. It was found that electropulsing improved the microhardness dramatically both in the influential depth and maximum value, compared with the only ultrasonic-shocked sample. It's indicated that refined surface layer with nanocrystalline and improved microhardness were obtained on account of surface severe plastic deformation, dynamic recrystallization (DRX) and phase change, which was implemented at relative low temperature and high strain rate/capacity due to the coupling of the thermal and athermal effects of EUS. It's different from conventional experiments and theory. It's discussed that the positive contributions of EPT in the thermodynamics and kinetics of microstructure and properties change were attributed to the reduction of nucleation energy barrier and acceleration of atomic diffusion. Therefore, it's supposed that EUS is an energy-saving and high-efficiency method of surface treatment technique with the help of high-energy electropulses, which is promising in cost reduction of the surface engineering and energy management. The work is supported by National Natural Science Foundation of China (No. 50571048) and Shenzhen science and technology research funding project of China (No. SGLH20121008144756946).
The Norwegian Earth System Model, NorESM1-M - Part 2: Climate response and scenario projections
NASA Astrophysics Data System (ADS)
Iversen, T.; Bentsen, M.; Bethke, I.; Debernard, J. B.; Kirkevåg, A.; Seland, Ø.; Drange, H.; Kristjánsson, J. E.; Medhaug, I.; Sand, M.; Seierstad, I. A.
2012-09-01
The NorESM1-M simulation results for CMIP5 (http://cmip-pcmdi.llnl.gov/cmip5/index.html) are described and discussed. Together with the accompanying paper by Bentsen et al. (2012), this paper documents that NorESM1-M is a valuable global climate model for research and for providing complementary results to the evaluation of possible man made climate change. NorESM is based on the model CCSM4 operated at NCAR on behalf of many contributors in USA. The ocean model is replaced by a developed version of MICOM and the atmospheric model is extended with on-line calculations of aerosols, their direct effect, and their indirect effect on warm clouds. Model validation is presented in a companion paper (Bentsen et al., 2012). NorESM1-M is estimated to have equilibrium climate sensitivity slightly smaller than 2.9 K, a transient climate response just below 1.4 K, and is less sensitive than most other models. Cloud feedbacks damp the response, and a strong AMOC reduces the heat fraction available for increasing near surface temperatures, for evaporation, and for melting ice. The future projections based on RCP scenarios yield global surface air temperature increase almost one standard deviation lower than a 15-model average. Summer sea-ice is projected to decrease considerably by 2100, and completely for RCP8.5. The AMOC is projected to reduce by 12%, 15-17%, and 32% for the RCP2.6, 4.5, 6.0 and 8.5 respectively. Precipitation is projected to increase in the tropics, decrease in the subtropics and in southern parts of the northern extra-tropics during summer, and otherwise increase in most of the extra-tropics. Changes in the atmospheric water cycle indicate that precipitation events over continents will become more intense and dry spells more frequent. Extra-tropical storminess in the Northern Hemisphere is projected to shift northwards. There are indications of more frequent spring and summer blocking in the Euro-Atlantic sectors and that ENSO events weaken but appear more frequent. These indications are uncertain because of biases in the model's representation of present-day conditions. There are indications that positive phase PNA and negative phase NAO become less frequent under the RCP8.5 scenario, but also this result is considered uncertain. Single-forcing experiments indicate that aerosols and greenhouse gases produce similar geographical patterns of response for near surface temperature and precipitation. These patterns tend to have opposite sign, with important exceptions for precipitation at low latitudes. The asymmetric aerosol effects between the two hemispheres leads to a southward displacement of ITCZ. Both forcing agents thus tend to reduce northern hemispheric subtropical precipitation.
NASA Astrophysics Data System (ADS)
Goelzer, Heiko; Nowicki, Sophie; Edwards, Tamsin; Beckley, Matthew; Abe-Ouchi, Ayako; Aschwanden, Andy; Calov, Reinhard; Gagliardini, Olivier; Gillet-Chaulet, Fabien; Golledge, Nicholas R.; Gregory, Jonathan; Greve, Ralf; Humbert, Angelika; Huybrechts, Philippe; Kennedy, Joseph H.; Larour, Eric; Lipscomb, William H.; Le clec'h, Sébastien; Lee, Victoria; Morlighem, Mathieu; Pattyn, Frank; Payne, Antony J.; Rodehacke, Christian; Rückamp, Martin; Saito, Fuyuki; Schlegel, Nicole; Seroussi, Helene; Shepherd, Andrew; Sun, Sainan; van de Wal, Roderik; Ziemen, Florian A.
2018-04-01
Earlier large-scale Greenland ice sheet sea-level projections (e.g. those run during the ice2sea and SeaRISE initiatives) have shown that ice sheet initial conditions have a large effect on the projections and give rise to important uncertainties. The goal of this initMIP-Greenland intercomparison exercise is to compare, evaluate, and improve the initialisation techniques used in the ice sheet modelling community and to estimate the associated uncertainties in modelled mass changes. initMIP-Greenland is the first in a series of ice sheet model intercomparison activities within ISMIP6 (the Ice Sheet Model Intercomparison Project for CMIP6), which is the primary activity within the Coupled Model Intercomparison Project Phase 6 (CMIP6) focusing on the ice sheets. Two experiments for the large-scale Greenland ice sheet have been designed to allow intercomparison between participating models of (1) the initial present-day state of the ice sheet and (2) the response in two idealised forward experiments. The forward experiments serve to evaluate the initialisation in terms of model drift (forward run without additional forcing) and in response to a large perturbation (prescribed surface mass balance anomaly); they should not be interpreted as sea-level projections. We present and discuss results that highlight the diversity of data sets, boundary conditions, and initialisation techniques used in the community to generate initial states of the Greenland ice sheet. We find good agreement across the ensemble for the dynamic response to surface mass balance changes in areas where the simulated ice sheets overlap but differences arising from the initial size of the ice sheet. The model drift in the control experiment is reduced for models that participated in earlier intercomparison exercises.
Goelzer, Heiko; Nowicki, Sophie; Edwards, Tamsin; ...
2018-04-19
Earlier large-scale Greenland ice sheet sea-level projections (e.g. those run during the ice2sea and SeaRISE initiatives) have shown that ice sheet initial conditions have a large effect on the projections and give rise to important uncertainties. Here, the goal of this initMIP-Greenland intercomparison exercise is to compare, evaluate, and improve the initialisation techniques used in the ice sheet modelling community and to estimate the associated uncertainties in modelled mass changes. initMIP-Greenland is the first in a series of ice sheet model intercomparison activities within ISMIP6 (the Ice Sheet Model Intercomparison Project for CMIP6), which is the primary activity within themore » Coupled Model Intercomparison Project Phase 6 (CMIP6) focusing on the ice sheets. Two experiments for the large-scale Greenland ice sheet have been designed to allow intercomparison between participating models of (1) the initial present-day state of the ice sheet and (2) the response in two idealised forward experiments. The forward experiments serve to evaluate the initialisation in terms of model drift (forward run without additional forcing) and in response to a large perturbation (prescribed surface mass balance anomaly); they should not be interpreted as sea-level projections. We present and discuss results that highlight the diversity of data sets, boundary conditions, and initialisation techniques used in the community to generate initial states of the Greenland ice sheet. We find good agreement across the ensemble for the dynamic response to surface mass balance changes in areas where the simulated ice sheets overlap but differences arising from the initial size of the ice sheet. The model drift in the control experiment is reduced for models that participated in earlier intercomparison exercises.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Goelzer, Heiko; Nowicki, Sophie; Edwards, Tamsin
Earlier large-scale Greenland ice sheet sea-level projections (e.g. those run during the ice2sea and SeaRISE initiatives) have shown that ice sheet initial conditions have a large effect on the projections and give rise to important uncertainties. Here, the goal of this initMIP-Greenland intercomparison exercise is to compare, evaluate, and improve the initialisation techniques used in the ice sheet modelling community and to estimate the associated uncertainties in modelled mass changes. initMIP-Greenland is the first in a series of ice sheet model intercomparison activities within ISMIP6 (the Ice Sheet Model Intercomparison Project for CMIP6), which is the primary activity within themore » Coupled Model Intercomparison Project Phase 6 (CMIP6) focusing on the ice sheets. Two experiments for the large-scale Greenland ice sheet have been designed to allow intercomparison between participating models of (1) the initial present-day state of the ice sheet and (2) the response in two idealised forward experiments. The forward experiments serve to evaluate the initialisation in terms of model drift (forward run without additional forcing) and in response to a large perturbation (prescribed surface mass balance anomaly); they should not be interpreted as sea-level projections. We present and discuss results that highlight the diversity of data sets, boundary conditions, and initialisation techniques used in the community to generate initial states of the Greenland ice sheet. We find good agreement across the ensemble for the dynamic response to surface mass balance changes in areas where the simulated ice sheets overlap but differences arising from the initial size of the ice sheet. The model drift in the control experiment is reduced for models that participated in earlier intercomparison exercises.« less
Ashfaq, Moetasim; Rastogi, Deeksha; Mei, Rui; ...
2016-09-01
We present high-resolution near-term ensemble projections of hydro-climatic changes over the contiguous U.S. using a regional climate model (RegCM4) that dynamically downscales 11 Global Climate Models from the 5th phase of Coupled Model Inter-comparison Project at 18km horizontal grid spacing. All model integrations span 41 years in the historical period (1965 – 2005) and 41 years in the near-term future period (2010 – 2050) under Representative Concentration Pathway 8.5 and cover a domain that includes the contiguous U.S. and parts of Canada and Mexico. Should emissions continue to rise, surface temperatures in every region within the U.S. will reach amore » new climate norm well before mid 21st century regardless of the magnitudes of regional warming. Significant warming will likely intensify the regional hydrological cycle through the acceleration of the historical trends in cold, warm and wet extremes. The future temperature response will be partly regulated by changes in snow hydrology over the regions that historically receive a major portion of cold season precipitation in the form of snow. Our results indicate the existence of the Clausius-Clapeyron scaling at regional scales where per degree centigrade rise in surface temperature will lead to a 7.4% increase in precipitation from extremes. More importantly, both winter (snow) and summer (liquid) extremes are projected to increase across the U.S. These changes in precipitation characteristics will be driven by a shift towards shorter and wetter seasons. Altogether, projected changes in the regional hydro-climate can have substantial impacts on the natural and human systems across the U.S.« less
NASA Astrophysics Data System (ADS)
Hopcroft, Peter O.; Valdes, Paul J.
2015-07-01
Previous work demonstrated a significant correlation between tropical surface air temperature and equilibrium climate sensitivity (ECS) in PMIP (Paleoclimate Modelling Intercomparison Project) phase 2 model simulations of the last glacial maximum (LGM). This implies that reconstructed LGM cooling in this region could provide information about the climate system ECS value. We analyze results from new simulations of the LGM performed as part of Coupled Model Intercomparison Project (CMIP5) and PMIP phase 3. These results show no consistent relationship between the LGM tropical cooling and ECS. A radiative forcing and feedback analysis shows that a number of factors are responsible for this decoupling, some of which are related to vegetation and aerosol feedbacks. While several of the processes identified are LGM specific and do not impact on elevated CO2 simulations, this analysis demonstrates one area where the newer CMIP5 models behave in a qualitatively different manner compared with the older ensemble. The results imply that so-called Earth System components such as vegetation and aerosols can have a significant impact on the climate response in LGM simulations, and this should be taken into account in future analyses.
Technical approach to groundwater restoration. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1993-11-01
The Technical Approach to Groundwater Restoration (TAGR) provides general technical guidance to implement the groundwater restoration phase of the Uranium Mill Tailings Remedial Action (UMTRA) Project. The TAGR includes a brief overview of the surface remediation and groundwater restoration phases of the UMTRA Project and describes the regulatory requirements, the National Environmental Policy Act (NEPA) process, and regulatory compliance. A section on program strategy discusses program optimization, the role of risk assessment, the observational approach, strategies for meeting groundwater cleanup standards, and remedial action decision-making. A section on data requirements for groundwater restoration evaluates the data quality objectives (DQO) andmore » minimum data required to implement the options and comply with the standards. A section on sits implementation explores the development of a conceptual site model, approaches to site characterization, development of remedial action alternatives, selection of the groundwater restoration method, and remedial design and implementation in the context of site-specific documentation in the site observational work plan (SOWP) and the remedial action plan (RAP). Finally, the TAGR elaborates on groundwater monitoring necessary to evaluate compliance with the groundwater cleanup standards and protection of human health and the environment, and outlines licensing procedures.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schwartz, Justin
Here we report the results from a project aimed at developing a fully superconducting joint between two REBCO coated conductors using electric field processing (EFP). Due to a reduction in the budget and time period of this contract, we reduced the project scope and focused first on the key scientific issues for forming a strong bond between conductors, and subsequently focused on improving through-the-joint transport. A modified timeline and task list is shown in Table 1, summarizing accomplishments to date. In the first period, we accomplished initial surface characterization as well as rounds of EFP experiments to begin to understandmore » processing parameters which produce well-bonded tapes. In the second phase, we explored the effects of two fundamental EFP parameters, voltage and pressure, and the limitations they place on the process. In the third phase, we achieved superconducting joints and established base characteristics of both the bonding process and the types of tapes best suited to this process. Finally, we investigated some of the parameters related to kinetics which appeared inhibit joint quality and performance.« less
Stream channel cross sections for a reach of the Boise River in Ada County, Idaho
Hortness, Jon E.; Werner, Douglas C.
1999-01-01
The Federal Emergency Management Agency produces maps of areas that are likely to be inundated during major floods, usually the 100-year, or 1-percent probability, flood. The maps, called Flood Insurance Rate Maps, are used to determine flood insurance rates for homes, businesses, or other structures located in flood-prone areas. State and local governments also use these maps for help with, among other things, development planning and disaster mitigation. During the period October 1997 through December 1998, the initial phase of a hydraulic analysis project of the Boise River from Barber Dam to the Ada/Canyon County boundary, the U.S. Geological Survey collected stream channel cross-section data at 238 locations along the river and documented 108 elevation reference marks established for horizontal and vertical control. In the final phase of the project, the Survey will use these data to determine water-surface elevations for the 10-, 50-, 100-, and 500-year floods and to define floodway limits. The Federal Emergency Management Agency will use the results of this hydraulic analysis to update the 100- and 500-year flood boundaries and the floodway limits on their Flood Insurance Rate Maps.
Development and Testing of the Phase 0 Autonomous Formation Flight Research System
NASA Technical Reports Server (NTRS)
Petersen, Shane; Fantini, Jay; Norlin, Ken; Theisen, John; Krasiewski, Steven
2004-01-01
The Autonomous Formation Flight (AFF) project was initiated in 1995 to demonstrate at least 10-percent drag reduction by positioning a trailing aircraft in the wingtip vortex of a leading aircraft. If successful, this technology would provide increased fuel savings, reduced emissions, and extended flight duration for fleet aircraft flying in formation. To demonstrate this technology, the AFF project at NASA Dryden Flight Research Center developed a system architecture incorporating two F-18 aircraft flying in leading-trailing formation. The system architecture has been designed to allow the trailing aircraft to maintain station-keeping position relative to the leading aircraft within +/-10 ft. Development of this architecture would be directed at the design and development of a computing system to feed surface position commands into the flight control computers, thereby controlling the longitudinal and lateral position of the trailing aircraft. In addition, modification to the instrumentation systems of both aircraft, pilot displays, and a means of broadcasting the leading aircraft inertial and global positioning system-based positional data to the trailing aircraft would be needed. This presentation focuses on the design and testing of the AFF Phase 0 research system.
Mutual influence of molecular diffusion in gas and surface phases
NASA Astrophysics Data System (ADS)
Hori, Takuma; Kamino, Takafumi; Yoshimoto, Yuta; Takagi, Shu; Kinefuchi, Ikuya
2018-01-01
We develop molecular transport simulation methods that simultaneously deal with gas- and surface-phase diffusions to determine the effect of surface diffusion on the overall diffusion coefficients. The phenomenon of surface diffusion is incorporated into the test particle method and the mean square displacement method, which are typically employed only for gas-phase transport. It is found that for a simple cylindrical pore, the diffusion coefficients in the presence of surface diffusion calculated by these two methods show good agreement. We also confirm that both methods reproduce the analytical solution. Then, the diffusion coefficients for ink-bottle-shaped pores are calculated using the developed method. Our results show that surface diffusion assists molecular transport in the gas phase. Moreover, the surface tortuosity factor, which is known to be uniquely determined by physical structure, is influenced by the presence of gas-phase diffusion. This mutual influence of gas-phase diffusion and surface diffusion indicates that their simultaneous calculation is necessary for an accurate evaluation of the diffusion coefficients.
NASA Astrophysics Data System (ADS)
Turner, Andrew; Bhat, Ganapati; Evans, Jonathan; Madan, Ranju; Marsham, John; Martin, Gill; Mitra, Ashis; Mrudula, Gm; Parker, Douglas; Pattnaik, Sandeep; Rajagopal, En; Taylor, Christopher; Tripathi, Sachchida
2017-04-01
The INCOMPASS project uses data from a field and aircraft measurement campaign during the 2016 monsoon onset to better understand and predict monsoon rainfall. The monsoon supplies the majority of water in South Asia, however modelling and forecasting the monsoon from days to the season ahead is limited by large model errors that develop quickly. Likely problems lie in physical parametrizations such as convection, the boundary layer and land surface. At the same time, lack of detailed observations prevents more thorough understanding of monsoon circulation and its interaction with the land surface; a process governed by boundary layer and convective cloud dynamics. From May to July 2016, INCOMPASS used a modified BAe-146 jet aircraft operated by the UK Facility for Airborne Atmospheric Measurements (FAAM), for the first project of this scale in India. The India and UK team flew around 100 hours of science sorties from bases in northern and southern India. Flights from Lucknow in the northern plains took measurements to the west and southeast to allow sampling of the complete contrast from dry desert air to the humid environment over the north Bay of Bengal. These routes were repeated in the pre-monsoon and monsoon phases, measuring contrasting surface and boundary layer structures. In addition, flights from the southern base in Bengaluru measured contrasts from the Arabian Sea, across the intense rains of the Western Ghats mountains, over the rain shadow in southeast India and over the southern Bay of Bengal. Flight planning was performed with the aid of forecasts from a new UK Met Office 4km limited area model. INCOMPASS also installed a network of surface flux towers, as well as operating a cloud-base ceilometer and performing intensive radiosonde launches from a supersite in Kanpur. Here we will outline preliminary results from the field campaign including new observations of the surface, boundary layer structure and atmospheric profiles from aircraft data. We also include initial results from nested high-resolution modelling experiments of the 2016 monsoon, at a resolution of 4km in comparison with bespoke regional forecasts run throughout the field campaign.
Cronin, Matthew John; Wharton, Samuel; Al-Radaideh, Ali; Constantinescu, Cris; Evangelou, Nikos; Bowtell, Richard; Gowland, Penny Anne
2016-06-01
The aim of this study was to compare the use of high-resolution phase and QSM images acquired at ultra-high field in the investigation of multiple sclerosis (MS) lesions with peripheral rings, and to discuss their usefulness for drawing inferences about underlying tissue composition. Thirty-nine Subjects were scanned at 7 T, using 3D T 2*-weighted and T 1-weighted sequences. Phase images were then unwrapped and filtered, and quantitative susceptibility maps were generated using a thresholded k-space division method. Lesions were compared visually and using a 1D profiling algorithm. Lesions displaying peripheral rings in the phase images were identified in 10 of the 39 subjects. Dipolar projections were apparent in the phase images outside of the extent of several of these lesions; however, QSM images showed peripheral rings without such projections. These projections appeared ring-like in a small number of phase images where no ring was observed in QSM. 1D profiles of six well-isolated example lesions showed that QSM contrast corresponds more closely to the magnitude images than phase contrast. Phase images contain dipolar projections, which confounds their use in the investigation of tissue composition in MS lesions. Quantitative susceptibility maps correct these projections, providing insight into the composition of MS lesions showing peripheral rings.
Seepage phenomena on Mars at subzero temperature
NASA Astrophysics Data System (ADS)
Kereszturi, Akos; Möhlmann, Diedrich; Berczi, Szaniszlo; Ganti, Tibor; Horvath, Andras; Kuti, Adrienn; Pocs, Tamas; Sik, Andras; Szathmary, Eors
At the southern hemisphere of Mars seasonal slope structures emanating from Dark Dune Spots are visible on MGS MOC, and MRO HiRISE images. Based on their analysis two groups of streaks could be identified: diffuse and fan shaped ones forming in an earlier phase of local spring, probably by CO2 gas jets, and confined streaks forming only on steep slopes during a later seasonal phase. The dark color of the streaks may arise from the dark color of the dune grains where surface frost disappeared above them, or caused by the phase change of the water ice to liquid-like water, or even it may be influenced by the solutes of salts in the undercooled interfacial water The second group's morphology (meandering style, ponds at their end), morphometry, and related theoretical modelling suggest they may form by undercooled water that remains in liquid phase in a thin layer around solid grains. We analyzed sequence of images, temperature and topographic data of Russel (54S 12E), Richardson (72S 180E) and an unnamed crater (68S 2E) during southern spring. The dark streaks here show slow motion, with an average speed of meter/day, when the maximal daytime temperature is between 190 and 220 K. Based on thermophysical considerations a thin layer of interfacial water is inevitable on mineral surfaces under the present conditions of Mars. With 10 precipitable micrometer of atmospheric water vapor, liquid phase can be present down about 190 K. Under such conditions dark streaks may form by the movement of grains lubricatred by interfacial water. This possibility have various consequences on chemical, mechanical or even possible astrobiological processes on Mars. Acknowledgment: This work was supported by the ESA ECS-project No. 98004 and the Pro Renovanda Cultura Hungariae Foundation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hu, E; Lasio, G; Yi, B
2014-06-01
Purpose: The Iterative Subtraction Algorithm (ISA) method generates retrospectively a pre-selected motion phase cone-beam CT image from the full motion cone-beam CT acquired at standard rotation speed. This work evaluates ISA method with real lung patient data. Methods: The goal of the ISA algorithm is to extract motion and no- motion components form the full reconstruction CBCT. The workflow consists of subtracting from the full CBCT all of the undesired motion phases and obtain a motion de-blurred single-phase CBCT image, followed by iteration of this subtraction process. ISA is realized as follows: 1) The projections are sorted to various phases,more » and from all phases, a full reconstruction is performed to generate an image CTM. 2) Generate forward projections of CTM at the desired phase projection angles, the subtraction of projection and the forward projection will reconstruct a CTSub1, which diminishes the desired phase component. 3) By adding back the CTSub1 to CTm, no motion CBCT, CTS1, can be computed. 4) CTS1 still contains residual motion component. 5) This residual motion component can be further reduced by iteration.The ISA 4DCBCT technique was implemented using Varian Trilogy accelerator OBI system. To evaluate the method, a lung patient CBCT dataset was used. The reconstruction algorithm is FDK. Results: The single phase CBCT reconstruction generated via ISA successfully isolates the desired motion phase from the full motion CBCT, effectively reducing motion blur. It also shows improved image quality, with reduced streak artifacts with respect to the reconstructions from unprocessed phase-sorted projections only. Conclusion: A CBCT motion de-blurring algorithm, ISA, has been developed and evaluated with lung patient data. The algorithm allows improved visualization of a single phase motion extracted from a standard CBCT dataset. This study has been supported by National Institute of Health through R01CA133539.« less
NASA Technical Reports Server (NTRS)
Penskiy, Ivan (Inventor); Charalambides, Alexandros (Inventor); Bergbreiter, Sarah (Inventor)
2018-01-01
At least one tactile sensor includes an insulating layer and a conductive layer formed on the surface of the insulating layer. The conductive layer defines at least one group of flexible projections extending orthogonally from the surface of the insulating layer. The flexible projections include a major projection extending a distance orthogonally from the surface and at least one minor projection that is adjacent to and separate from the major projection wherein the major projection extends a distance orthogonally that is greater than the distance that the minor projection extends orthogonally. Upon a compressive force normal to, or a shear force parallel to, the surface, the major projection and the minor projection flex such that an electrical contact resistance is formed between the major projection and the minor projection. A capacitive tactile sensor is also disclosed that responds to the normal and shear forces.
NASA Astrophysics Data System (ADS)
Bhattarai, R.; Kalita, P. K.; Davidson, P. C.; Kuhlenschmidt, M. S.
2012-12-01
More than 3.5 million people die each year from a water related diseases in this world. Every 20 seconds, a child dies from a water-related illness. Even in a developed country like the United States, there have been at least 1870 outbreaks associated with drinking water during the period of 1920 to 2002, causing 883,806 illnesses. Most of these outbreaks are resulted due to the presence of microbial pathogens in drinking water. Rotavirus infection has been recognized as the most common cause of diarrhea in young children throughout the world. Laboratory experiments conducted at the University of Illinois have demonstrated that recovery of rotavirus has been significantly affected by climatic and soil-surface conditions like slope, soil types, and ground cover. The objective of this study is to simulate the fate and transport of Rotavirus in overland and near-surface flow using a process-based model. In order to capture the dynamics of sediment-bound pathogens, the Water Erosion Prediction Project (WEPP) is coupled with the pathogen transport model. Transport of pathogens in overland flow can be simulated mathematically by including terms for the concentration of the pathogens in the liquid phase (in suspension or free-floating) and the solid phase (adsorbed to the fine solid particles like clay and silt). Advection, adsorption, and decay processes are considered. The mass balance equations are solved using numerical technique to predict spatial and temporal changes in pathogen concentrations in two phases. Outputs from WEPP simulations (flow velocity, depth, saturated conductivity and the soil particle fraction exiting in flow) are transferred as input for the pathogen transport model. Three soil types and three different surface cover conditions have been used in the experimental investigations. Results from these conditions have been used in calibrating and validating the simulation results. Bare surface conditions have produced very good agreement between observed and predicted results; however, transport of pathogens from vegetated surface has been challenging. This paper will provide concepts of the pathogen transport model, integration with WEPP, and results obtained from the modeling framework.
NASA Astrophysics Data System (ADS)
Ghiselli, Alice; Merazzi, Marzio; Strini, Andrea; Margutti, Roberto; Mercuriali, Michele
2011-06-01
As karst systems are natural windows to the underground, speleology, combined with geological surveys, can be useful tools for helping understand the geological evolution of karst areas. In order to enhance the reconstruction of the structural setting in a gypsum karst area (Vena del Gesso, Romagna Apennines), a detailed analysis has been carried out on hypogeal data. Structural features (faults, fractures, tectonic foliations, bedding) have been mapped in the "Grotta del Re Tiberio" cave, in the nearby gypsum quarry tunnels and open pit benches. Five fracture systems and six fault systems have been identified. The fault systems have been further analyzed through stereographic projections and geometric-kinematic evaluations in order to reconstruct the relative chronology of these structures. This analysis led to the detection of two deformation phases. The results permitted linking of the hypogeal data with the surface data both at a local and regional scale. At the local scale, fracture data collected in the underground have been compared with previous authors' surface data coming from the quarry area. The two data sets show a very good correspondence, as every underground fracture system matches with one of the surface fracture system. Moreover, in the cave, a larger number of fractures belonging to each system could be mapped. At the regional scale, the two deformation phases detected can be integrated in the structural setting of the study area, thereby enhancing the tectonic interpretation of the area ( e.g., structures belonging to a new deformation phase, not reported before, have been identified underground). The structural detailed hypogeal survey has, thus, provided very useful data, both by integrating the existing information and revealing new data not detected at the surface. In particular, some small structures ( e.g., displacement markers and short fractures) are better preserved in the hypogeal environment than on the surface where the outcropping gypsum is more exposed to dissolution and recrystallization. The hypogeal geological survey, therefore, can be considered a powerful tool for integrating the surface and log data in order to enhance the reconstruction of the deformational history and to get a three-dimensional model of the bedrock in karst areas.
Status of the MiniCLEAN dark matter experiment
NASA Astrophysics Data System (ADS)
Rielage, Keith
2009-10-01
MiniCLEAN utilizes over 400 kg of liquid cryogen to detect nuclear recoils from WIMP dark matter with a projected sensitivity of 2x10-45 cm^2 for a mass of 100 GeV. The liquid cryogen is interchangeable between argon and neon to study the A^2 dependence of the potential signal and examine backgrounds. MiniCLEAN utilizes a unique modular design with spherical geometry to maximize the light yield using cold photomultiplier tubes in a single-phase detector. Pulse shape discrimination techniques are used to separate nuclear recoil signals from electron recoil backgrounds. Particular attention is being paid to mitigating the backgrounds from contamination of surfaces by radon daughters during assembly. The design and assembly status of the experiment will be discussed. The projected timeline and future plans for staging the experiment at SNOLAB in Sudbury, Canada will be presented.
NASA Technical Reports Server (NTRS)
Kuhl. Christopher A.
2009-01-01
The Aerial Regional-Scale Environmental Survey (ARES) is a Mars exploration mission concept with the goal of taking scientific measurements of the atmosphere, surface, and subsurface of Mars by using an airplane as the payload platform. ARES team first conducted a Phase-A study for a 2007 launch opportunity, which was completed in May 2003. Following this study, significant efforts were undertaken to reduce the risk of the atmospheric flight system, under the NASA Langley Planetary Airplane Risk Reduction Project. The concept was then proposed to the Mars Scout program in 2006 for a 2011 launch opportunity. This paper summarizes the design and development of the ARES airplane propulsion subsystem beginning with the inception of the ARES project in 2002 through the submittal of the Mars Scout proposal in July 2006.
MONITORING PARTICLES, SOOT, AND PAHS IN A HOME
The Atlanta Supersites project is the first of two Supersites projects to be established during Phase I of EPA's Supersites Program; Phase II is being established through a Request for Assistance. The other initial project is in Fresno, California. The Supersites Program is par...
13 CFR 305.9 - Project phasing and Investment disbursement.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Project phasing and Investment disbursement. 305.9 Section 305.9 Business Credit and Assistance ECONOMIC DEVELOPMENT ADMINISTRATION, DEPARTMENT OF COMMERCE PUBLIC WORKS AND ECONOMIC DEVELOPMENT INVESTMENTS Requirements for Approved Projects...
U10 : Trusted Truck(R) II (phase B).
DOT National Transportation Integrated Search
2009-01-01
Phase B of the Trusted Truck II project built on the system developed in Phase A (or Year 1). For the implementation portion of the project, systems were added to the trailer to provide additional diagnostic trailer data that can be sent to the TTM...
EMSODEV and EPOS-IP: key findings for effective management of EU research infrastructure projects
NASA Astrophysics Data System (ADS)
Materia, Paola; Bozzoli, Sabrina; Beranzoli, Laura; Cocco, Massimo; Favali, Paolo; Freda, Carmela; Sangianantoni, Agata
2017-04-01
EMSO (European Multidisciplinary Seafloor and water-column Observatory, http://www.emso-eu.org) and EPOS (European Plate Observing System, https://www.epos-ip.org) are pan-European Research Infrastructures (RIs) in the ESFRI 2016 Roadmap. EMSO has recently become an ERIC (European Research Infrastructure Consortium), whilst EPOS application is in progress. Both ERICs will be hosted in Italy and the "Representing Entity" is INGV. EMSO consists of oceanic environment observation systems spanning from the Arctic through the Atlantic and Mediterranean, to the Black Sea for long-term, high-resolution, real-time monitoring of natural and man-induced processes such as hazards, climate, and marine ecosystems changes to study their evolution and interconnections. EPOS aims at creating a pan-European infrastructure for solid Earth science to support a safe and sustainable society. EPOS will enable innovative multidisciplinary research for a better understanding of Earth's physical and chemical processes controlling earthquakes, volcanic eruptions, ground instability, tsunami, and all those processes driving tectonics and Earth's surface dynamics. Following the conclusion of their Preparatory Phases the two RIs are now in their Implementation Phase still supported by the EC through the EMSODEV and EPOS-IP projects, both run by dedicated Project Management Offices at INGV with sound experience in EU projects. EMSODEV (H2020 project, 2015-2018) involves 11 partners and 9 associate partners and aims at improving the harmonization among the EMSO ERIC observation systems through the realization of EMSO Generic Instrument Modules (EGIMs), and a Data Management Platform (DMP) to implement interoperability and standardization. The DMP will provide access to data from all EMSO nodes, providing a unified, homogeneous, infrastructure-scale and user-oriented platform integrated with the increased measurement capabilities and functions provided by the EGIMs. EPOS IP (H2020 project, 2015-2019) is a project of 47 partners, 6 associate partners and several international organizations for a total of 25 countries involved. EPOS IP is a key step in EPOS' mission of a pan-European Earth science integrated platform. It will deliver not only a suite of domain-specific and multidisciplinary data and services in one platform, but also the legal, governance and financial frameworks to ensure the infrastructure future operation and sustainability (EPOS ERIC). INGV experience over the years indicates that effective management of EU RIs projects should contain 5 basic elements: 1.Defined life cycle and milestones: Map of phases, deliverables, key milestones and sufficiency criteria for each group involved in the project using project management tools and software. 2.Shared organization, systems, roles: Defined roles for team members and responsibilities for functional managers are crucial. Similarly, a system of communication and team involvement is essential to success. Leadership and interpersonal/organizational skills are also important. 3.Quality assurance: Quality dimension should be aligned to the project objectives and specific criteria should be identified for each phase of the project. 4.Tracking and variance analysis: Regular reports and periodic meetings of the teams are crucial to identify when things are off target. Schedule slips, cost overruns, open issues, new risks and problems must be dealt with as early as possible. 5.Impact assessment by monitoring the achievement of results and socio-economic impact.
2D and 3D X-ray phase retrieval of multi-material objects using a single defocus distance.
Beltran, M A; Paganin, D M; Uesugi, K; Kitchen, M J
2010-03-29
A method of tomographic phase retrieval is developed for multi-material objects whose components each has a distinct complex refractive index. The phase-retrieval algorithm, based on the Transport-of-Intensity equation, utilizes propagation-based X-ray phase contrast images acquired at a single defocus distance for each tomographic projection. The method requires a priori knowledge of the complex refractive index for each material present in the sample, together with the total projected thickness of the object at each orientation. The requirement of only a single defocus distance per projection simplifies the experimental setup and imposes no additional dose compared to conventional tomography. The algorithm was implemented using phase contrast data acquired at the SPring-8 Synchrotron facility in Japan. The three-dimensional (3D) complex refractive index distribution of a multi-material test object was quantitatively reconstructed using a single X-ray phase-contrast image per projection. The technique is robust in the presence of noise, compared to conventional absorption based tomography.
Mapping of information and identification of construction waste at project life cycle
NASA Astrophysics Data System (ADS)
Wibowo, Mochamad Agung; Handayani, Naniek Utami; Nurdiana, Asri; Sholeh, Moh Nur; Pamungkas, Gita Silvia
2018-03-01
The development of construction project towards green construction is needed in order to improve the efficiency of construction projects. One that needs to be minimized is construction waste. Construction waste is waste generated from construction project activities, both solid waste and non solid waste. More specifically, the waste happens at every phase of the project life cycle. Project life cycle are the stage of idea, design, construction, and operation/maintenance. Each phase is managed by different stakeholders. Therefore it requires special handling from the involved stakeholders. The objective of the study is to map the information and identify the waste at each phase of the project life cycle. The purpose of mapping is to figure out the process of information and product flow and with its timeline. This mapping used Value Stream Mapping (VSM). Identification of waste was done by distributing questionnaire to respondents to know the waste according to owner, consultant planner, contractor, and supervisory consultant. The result of the study is the mapping of information flow and product flow at the phases of idea, design, construction, and operation/ maintenance.
Analysis of Alpha Backgrounds in DarkSide-50
NASA Astrophysics Data System (ADS)
Monte, Alissa; DarkSide Collaboration
2017-01-01
DarkSide-50 is the current phase of the DarkSide direct dark matter search program, operating underground at the Laboratori Nazionali del Gran Sasso in Italy. The detector is a dual-phase argon Time Projection Chamber (TPC), designed for direct detection of Weakly Interacting Massive Particles, and housed within an active veto system of liquid scintillator and water Cherenkov detectors. Since switching to a target of low radioactivity argon extracted from underground sources in April, 2016, the background is no longer dominated by naturally occurring 39Ar. However, alpha backgrounds from radon and its daughters remain, both from the liquid argon bulk and internal detector surfaces. I will present details of the analysis used to understand and quantify alpha backgrounds, as well as to understand other types of radon contamination that may be present, and our sensitivity to them.
Buratti, B.J.; Hicks, M.D.; Nettles, J.; Staid, M.; Pieters, C.M.; Sunshine, J.; Boardman, J.; Stone, T.C.
2011-01-01
The USGS's Robotic Lunar Observatory (ROLO) dedicated ground-based lunar calibration project obtained photometric observations of the Moon over the spectral range attainable from Earth (0.347-2.39 ??m) and over solar phase angles of 1.55??-97??. From these observations, we derived empirical lunar surface solar phase functions for both the highlands and maria that can be used for a wide range of applications. The functions can be used to correct for the effects of viewing geometry to produce lunar mosaics, spectra, and quick-look products for future lunar missions and ground-based observations. Our methodology can be used for a wide range of objects for which multiply scattered radiation is not significant, including all but the very brightest asteroids and moons. Copyright 2011 by the American Geophysical Union.
Phases of five-dimensional theories, monopole walls, and melting crystals
NASA Astrophysics Data System (ADS)
Cherkis, Sergey A.
2014-06-01
Moduli spaces of doubly periodic monopoles, also called monopole walls or monowalls, are hyperkähler; thus, when four-dimensional, they are self-dual gravitational instantons. We find all monowalls with lowest number of moduli. Their moduli spaces can be identified, on the one hand, with Coulomb branches of five-dimensional supersymmetric quantum field theories on 3 × T 2 and, on the other hand, with moduli spaces of local Calabi-Yau metrics on the canonical bundle of a del Pezzo surface. We explore the asymptotic metric of these moduli spaces and compare our results with Seiberg's low energy description of the five-dimensional quantum theories. We also give a natural description of the phase structure of general monowall moduli spaces in terms of triangulations of Newton polygons, secondary polyhedra, and associahedral projections of secondary fans.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hermele, Michael; Chen, Xie
Here, we introduce a method, dubbed the flux-fusion anomaly test, to detect certain anomalous symmetry fractionalization patterns in two-dimensional symmetry-enriched topological (SET) phases. We focus on bosonic systems with Z2 topological order and a symmetry group of the form G=U(1)xG', where G' is an arbitrary group that may include spatial symmetries and/or time reversal. The anomalous fractionalization patterns we identify cannot occur in strictly d=2 systems but can occur at surfaces of d=3 symmetry-protected topological (SPT) phases. This observation leads to examples of d=3 bosonic topological crystalline insulators (TCIs) that, to our knowledge, have not previously been identified. In somemore » cases, these d=3 bosonic TCIs can have an anomalous superfluid at the surface, which is characterized by nontrivial projective transformations of the superfluid vortices under symmetry. The basic idea of our anomaly test is to introduce fluxes of the U(1) symmetry and to show that some fractionalization patterns cannot be extended to a consistent action of G' symmetry on the fluxes. For some anomalies, this can be described in terms of dimensional reduction to d=1 SPT phases. We apply our method to several different symmetry groups with nontrivial anomalies, including G=U(1)×Z T 2 and G=U(1)×Z P 2, where Z T 2 and Z P 2 are time-reversal and d=2 reflection symmetry, respectively.« less
NASA Astrophysics Data System (ADS)
da Silva, Thiago H.; Nelson, Eric B.; Williamson, Izaak; Efaw, Corey M.; Sapper, Erik; Hurley, Michael F.; Li, Lan
2018-05-01
First-principles density functional theory-based calculations were performed to study θ-phase Al2Cu, S-phase Al2CuMg surface stability, as well as their interactions with water molecules and chloride (Cl-) ions. These secondary phases are commonly found in aluminum-based alloys and are initiation points for localized corrosion. Density functional theory (DFT)-based simulations provide insight into the origins of localized (pitting) corrosion processes of aluminum-based alloys. For both phases studied, Cl- ions cause atomic distortions on the surface layers. The nature of the distortions could be a factor to weaken the interlayer bonds in the Al2Cu and Al2CuMg secondary phases, facilitating the corrosion process. Electronic structure calculations revealed not only electron charge transfer from Cl- ions to alloy surface but also electron sharing, suggesting ionic and covalent bonding features, respectively. The S-phase Al2CuMg structure has a more active surface than the θ-phase Al2Cu. We also found a higher tendency of formation of new species, such as Al3+, Al(OH)2+, HCl, AlCl2+, Al(OH)Cl+, and Cl2 on the S-phase Al2CuMg surface. Surface chemical reactions and resultant species present contribute to establishment of local surface chemistry that influences the corrosion behavior of aluminum alloys.
A Reflection on the Effects of the 985 Project
ERIC Educational Resources Information Center
Ying, Cheng
2011-01-01
China's 985 Project, which came after the 211 Project, is a key program of the Chinese government to create world-class universities and high-level research universities. The central government invested a total of RMB32.9 billion in special funds for phase I (1999-2001) and phase II (2004-2007) of the project, assisting thirty-nine universities.…
The CERES S'COOL Project: Development and Operational Phases
NASA Technical Reports Server (NTRS)
Chambers, Lin H.; Young, David F.; Racel, Anne M.
1998-01-01
As part of NASA's Mission to Planet Earth, the first Clouds and the Earth's Radiant Energy System (CERES) instrument will be launched on the Tropical Rainfall Measuring Mission (TRMM) spacecraft from the Tanegashima launch site in Japan in November 1997. The instrument will measure the radiation budget incoming and outgoing radiant energy - of the Earth. The major feature of interest is clouds, which play a very strong role in regulating our climate. CERES will identify clear and cloudy regions and determine cloud physical and microphysical properties using imager data from a companion instrument. Validation efforts for the remote sensing algorithms will be intensive. As one component of the validation, the S'COOL (Students' Cloud Observations On-Line) project will involve school children around the globe in making ground truth measurements at the time of a CERES overpass. They will report cloud type, height, fraction, and opacity, as well as the local surface conditions. Their observations will be collected at the NASA Langley Distributed Active Archive Center (DAAC) and made available over the Internet for educational purposes as well as for use by the CERES Science Team in validation efforts. Pilot testing of the S'COOL project began in January 1997 with two local schools in Southeastern Virginia and one remote site in Montana. National testing in April 1997 involved 8 schools (grades 3 to high school) across the United States. Global testing will be carried out in October 1997. Details of the S'COOL project, which is mainly Internet-based, are being developed in each of these phases according to feedback received from participants. In 1998, when the CERES instrument is operational, a global observer network should be in place providing useful information to the scientists and learning opportunities to the students. Broad participation in the S'COOL project is planned, both to obtain data from a wide range of geographic areas, and to involve as many students as possible in learning about clouds and atmospheric science. This paper reports on the development phase of the S'COOL project, including the reaction of the teachers and students who have been involved. It describes the operational state of the S'COOL network, and identifies opportunities for additional participants.
Individualized In-Service Teacher Education. (Project IN-STEP). Evaluation Report, Phase II.
ERIC Educational Resources Information Center
Thurber, John C.
Phase 2 of Project IN-STEP was conducted to revise, refine, and conduct further field testing of a new inservice teacher education model. The method developed (in Phase 1--see ED 003 905 for report) is an individualized, multi-media approach. Revision activities, based on feedback provided for Phase 1, include the remaking of six videotape…
In-line phase contrast micro-CT reconstruction for biomedical specimens.
Fu, Jian; Tan, Renbo
2014-01-01
X-ray phase contrast micro computed tomography (micro-CT) can non-destructively provide the internal structure information of soft tissues and low atomic number materials. It has become an invaluable analysis tool for biomedical specimens. Here an in-line phase contrast micro-CT reconstruction technique is reported, which consists of a projection extraction method and the conventional filter back-projection (FBP) reconstruction algorithm. The projection extraction is implemented by applying the Fourier transform to the forward projections of in-line phase contrast micro-CT. This work comprises a numerical study of the method and its experimental verification using a biomedical specimen dataset measured at an X-ray tube source micro-CT setup. The numerical and experimental results demonstrate that the presented technique can improve the imaging contrast of biomedical specimens. It will be of interest for a wide range of in-line phase contrast micro-CT applications in medicine and biology.
Iterative projection algorithms for ab initio phasing in virus crystallography.
Lo, Victor L; Kingston, Richard L; Millane, Rick P
2016-12-01
Iterative projection algorithms are proposed as a tool for ab initio phasing in virus crystallography. The good global convergence properties of these algorithms, coupled with the spherical shape and high structural redundancy of icosahedral viruses, allows high resolution phases to be determined with no initial phase information. This approach is demonstrated by determining the electron density of a virus crystal with 5-fold non-crystallographic symmetry, starting with only a spherical shell envelope. The electron density obtained is sufficiently accurate for model building. The results indicate that iterative projection algorithms should be routinely applicable in virus crystallography, without the need for ancillary phase information. Copyright © 2016 Elsevier Inc. All rights reserved.
The Far-UV Albedo of the Moon Determined from Dayside LAMP Observations
NASA Astrophysics Data System (ADS)
Bullock, Mark A.; Retherford, K. D.; Gladstone, R.; Greathouse, T. K.; Mandt, K. E.; Hendrix, A. R.; Feldman, P. D.; Miles, P. F.; Egan, A. F.
2013-10-01
The Lyman Alpha Mapping Project (LAMP) onboard the Lunar Reconnaissance Orbiter (LRO) has been recording far-UV photons reflected from the lunar surface almost continuously since December 2009 (Gladstone et al., 2010). One photon at a time, LAMP builds up spectra from 575 to 1965 Å with a resolution of 26 Å. We will present 3 years of accumulated LAMP lunar dayside spectral maps and derive the lunar geometric albedo spectrum for a range of phase angles. These LAMP observations can thus be used to reconstruct the lunar far-UV photometric function and refine photometric models of the lunar surface (Hapke, 1963; Lucke et al., 1976). We will also compare LAMP lunar dayside albedo with the albedo from 820-1840 Å obtained by the Hopkins Ultraviolet Telescope (HUT) on the March 1995 Astro-2 Space Shuttle mission (Henry et al., 1995). The improved lunar photometric functions from our analysis of LAMP albedo spectra will enable a better quantitative assessment of how phase angle and composition affect the Moon’s reflectance in the far-UV. Gladstone, G. R., Stern, S. A., Retherford, K. D., Black, R. K., Slater, D. C., Davis, M. W., Versteeg, M. H., Persson, K. B., Parker, J. W., Kaufmann, D. E., Egan, A. F., Greathouse, T. K., Feldman, P. D., Hurley, D., Pryor, W. R., Hendrix, A. R., 2010. LAMP: The lyman alpha mapping project on NASA's lunar reconnaissance orbiter mission. Space Science Reviews. 150, 161-181. Hapke, B. W., 1963. A theoretical photometric function for the lunar surface. Journal of Geophysical Research. 68, 4571-4586. Henry, R. C., Feldman, P. D., Kruk, J. W., Davidsen, A. F., Durrance, S. T., 1995. Ultraviolet Albedo of the Moon with the Hopkins Ultraviolet Telescope. The Astrophysical Journal Letters. 454, L69. Lucke, R. L., Henry, R. C., Fastie, W. G., 1976. Far-ultraviolet albedo of the moon. The Astronomical Journal. 81, 1162-1169.
Cr(VI) Sorption by Nanosized FeS-Coated Sand
NASA Astrophysics Data System (ADS)
Park, M.; Jeong, H. Y.; Lee, S.; Kang, N.; Kim, K. H.; Choi, H. J.
2015-12-01
Cr(VI) sorption experiments were conducted as a function of pH (4.7, 7.0 and 9.7) using nanosized FeS-coated sand under anoxic environments. Under the experimental conditions, the sand used, with the FeS content of 0.068 mmol per 1 g sand, completely reduced the initially added Cr(VI) to Cr(III) over the pH range examined. The sorption of the once-reduced Cr(III) varied greatly with the solution pH. By the solution-phase analysis, significant amounts of Cr(III) remained as dissolved species at pH 4.7. On the other hands, dissolved Cr was below the detection limit (0.2 μM) at pH 7.0 and 9.7, indicating the greater sorption of Cr(III) at neutral to basic pH than acidic pH. From Cr-K edge X-ray absorption spectroscopy (XAS) analysis of the solid products, the sorbed Cr was shown to be present predominantly as trivalent state in all samples. Regardless of pH, the second coordination shell around Cr (i.e., the Cr-Cr(Fe) shell) was shown to be located at ~2.6 Å, which was far shorter than those in Cr(III)-bearing model compounds such as Cr(OH)3(s) and [Cr, Fe](OH)3(s). Furthermore, the coordination numbers of the second and third shells in the sorption samples (N = 0.7-1.8) were much lower than those in Cr(OH)3(s) and [Cr, Fe](OH)3(s). Taken together, the sorption of the once-reduced Cr(III) was likely to occur via surface-mediated processes (e.g., surface complexation and/or surface precipitation) rather than the bulk-phase precipitation. Financial support was provided by the "R&D Project on Environmental Management of Geologic CO2 Storage" from the KEITI (Project Number: 2014001810003).
Phase C/D program development plan. Volume 1: Program plan
NASA Technical Reports Server (NTRS)
1971-01-01
The Phase C/D definition of the Modular Space Station has been developed. The modular approach selected during the option period was evaluated, requirements were defined, and program definition and preliminary design were accomplished. The Space Station Project is covered in depth, the research applications module is limited to a project-level definition, and the shuttle operations are included for interface requirements identification, scheduling, and costing. Discussed in detail are: (1) baseline program and project descriptions; (2) phase project planning; (3) modular space station program schedule; (4) program management plan; (5) operations; (6) facilities; (7) logistics; and (8) manpower.
Implementation of a production Ada project: The GRODY study
NASA Technical Reports Server (NTRS)
Godfrey, Sara; Brophy, Carolyn Elizabeth
1989-01-01
The use of the Ada language and design methodologies that encourage full use of its capabilities have a strong impact on all phases of the software development project life cycle. At the National Aeronautics and Space Administration/Goddard Space Flight Center (NASA/GSFC), the Software Engineering Laboratory (SEL) conducted an experiment in parallel development of two flight dynamics systems in FORTRAN and Ada. The differences observed during the implementation, unit testing, and integration phases of the two projects are described and the lessons learned during the implementation phase of the Ada development are outlined. Included are recommendations for future Ada development projects.
W.A. Parish Post-Combustion CO{sub 2} Capture and Sequestration Project Phase 1 Definition
DOE Office of Scientific and Technical Information (OSTI.GOV)
Armpriester, Anthony; Smith, Roger; Scheriffius, Jeff
2014-02-01
For a secure and sustainable energy future, the United States (U.S.) must reduce its dependence on imported oil and reduce its emissions of carbon dioxide (CO{sub 2}) and other greenhouse gases (GHGs). To meet these strategic challenges, the U.S. wiU have to create fundamentally new technologies with performance levels far beyond what is now possible. Developing advanced post-combustion clean coal technologies for capturing CO{sub 2} from existing coal-fired power plants can play a major role in the country's transition to a sustainable energy future, especially when coupled with CO{sub 2}-enhanced oil recovery (CO{sub 2}-EOR). Pursuant to these goals, NRG Energy,more » Inc. (NRG) submitted an application and entered into a cost-shared collaboration with the U.S. Department of Energy (DOE) under Round 3 of the Clean Coal Power Initiative (CCPI) to advance low-emission coal technologies. The objective of the NRG W A Parish Post-Combustion CO{sub 2} Capture and Sequestration Demonstration Project is to establish the technical feasibility and economic viability of post-combustion CO{sub 2} capture using flue gas from an existing pulverized coal-fired boiler integrated with geologic sequestration via an enhanced oil recovery (EOR) process. To achieve these objectives, the project will be executed in three phases. Each phase represents a distinct aspect of the project execution. The project phases are: • Phase I. Project Definition/Front-End Engineering Design (FEED) • Phase ll. Detailed Engineering, Procurement & Construction • Phase III. Demonstration and Monitoring The purpose of Phase I is to develop the project in sufficient detail to facilitate the decision-making process in progressing to the next stage of project delivery. Phase n. This report provides a complete summary of the FEED study effort, including pertinent project background information, the scope of facilities covered, decisions, challenges, and considerations made regarding configuration and performance of the facility, along with the conceptual design and estimate results. The findings of this report should be considered conceptual in nature and are conditioned on the statements contained herein. The cost of preparing this report (including the FEED study described herein) was funded in part by a $167-million grant provided by the U.S. DOE.« less
NASA Technical Reports Server (NTRS)
Mastropietro, A. J.; Pauken, Michael; Sunada, Eric; Gray, Sandria
2013-01-01
The thermal design and analysis of the experimental Supersonic Flight Dynamics Test (SFDT) vehicle is presented. The SFDT vehicle is currently being designed as a platform to help demonstrate key technologies for NASA's Low Density Supersonic Decelerator (LDSD) project. The LDSD project is charged by NASA's Office of the Chief Technologist (OCT) with the task of advancing the state of the art in Mars Entry, Descent, and Landing (EDL) systems by developing and testing three new technologies required for landing heavier payloads on Mars. The enabling technologies under development consist of a large 33.5 meter diameter Supersonic Ringsail (SSRS) parachute and two different types of Supersonic Inflatable Aerodynamic Decelerator (SIAD) devices - a robotic class, SIAD-R, that inflates to a 6 meter diameter torus, and an exploration class, SIAD-E, that inflates to an 8 meter diameter isotensoid. As part of the technology development effort, the various elements of the new supersonic decelerator system must be tested in a Mars-like environment. This is currently planned to be accomplished by sending a series of SFDT vehicles into Earth's stratosphere. Each SFDT vehicle will be lifted to a stable float altitude by a large helium carrier balloon. Once at altitude, the SFDT vehicles will be released from their carrier balloon and spun up via spin motors to provide trajectory stability. An onboard third stage solid rocket motor will propel each test vehicle to supersonic flight in the upper atmosphere. After main engine burnout, each vehicle will be despun and testing of the deceleration system will begin: first an inflatable decelerator will be deployed around the aeroshell to increase the drag surface area, and then the large parachute will be deployed to continue the deceleration and return the vehicle back to the Earth's surface. The SFDT vehicle thermal system must passively protect the vehicle structure and its components from cold temperatures experienced during the ascent phase of the mission as well as from the extreme heat fluxes produced during the supersonic test phase by the main motor plume and aeroheating. The passive thermal design approach for the SFDT vehicle relies upon careful and complex bounding analysis of all three modes of heat transfer - conduction, convection, and radiation - coupled with a tightly managed transient power dissipation timeline for onboard electronics components throughout all mission phases.
NASA Astrophysics Data System (ADS)
Silvestri, M.; Musacchio, M.; Buongiorno, M. F.; Dini, L.
2009-04-01
The Project called Sistema Rischio Vulcanico (SRV) is funded by the Italian Space Agency (ASI) in the frame of the National Space Plan 2003-2005 under the Earth Observations section for natural risks management. The SRV Project is coordinated by the Istituto Nazionale di Geofisica e Vulcanologia (INGV) which is responsible at national level for the volcanic monitoring. The project philosophy is to implement, by incremental versions, specific modules which allow to process, store and visualize through Web GIS tools geophysical parameters suitable for volcanic risk management. The ASI-SRV is devoted to the development of an integrated system based on Earth Observation (EO) data to respond to specific needs of the Italian Civil Protection Department (DPC) and improve the monitoring of Italian active volcanoes during all the risk phases (Pre Crisis, Crisis and Post Crisis). The ASI-SRV system provides support to risk managers during the different volcanic activity phases and its results are addressed to the Italian Civil Protection Department (DPC). SRV provides the capability to manage the import many different EO data into the system, it maintains a repository where the acquired data have to be stored and generates selected volcanic products. The processing modules for EO Optical sensors data are based on procedures jointly developed by INGV and University of Modena. This procedures allow to estimate a number of parameters such as: surface thermal proprieties, gas, aerosol and ash emissions and to characterize the volcanic products in terms of composition and geometry. For the analysis of the surface thermal characteristics, the available algorithms allow to extract information during the prevention phase and during the Warning and Crisis phase. In the prevention phase the thermal analysis is directed to the identification of temperature variation on volcanic structure which may indicate a change in the volcanic activity state. At the moment the only sensor that shows good technical characteristics for the prevention phase is the ASTER sensor (90 m pixel) on NASA satellite TERRA. The product regarding the Crisis phase is mainly finalized to the estimation of the effusion rate for active lava flows, the algorithms for this product are well consolidated and could be applied to the low spatial resolution space sensors (eg. AVHRR, MODIS) and to high spatial resolution space sensors (eg. Hyperion, ASTER). A further class of products regards the analysis of degassing plumes and eruptive clouds. The analysis of the emitted gas species from degassing plume is usually performed trough ground networks of instruments based on the spectral behaviour of the gas species, although many volcanoes in the world do not have such permanent networks. The SRV system will produce information on the concentration and flux of sulphur dioxide (SO2) water vapour and volcanic aerosol optical thickness by means of ASTER, MODIS and HYPERION data on Etna test site. The analysis of ash clouds will be made by means of already consolidated procedures which uses low spatial resolution sensors with an high revisit time (eg. AVHRR, MSG, MODIS). For the Post Crisis phase the required products will be obtained through classification algorithms and spectral analysis operated by the scientific personnel of INGV and introduced in the system repository after the use of modules. The processing modules for EO RADAR sensors data for ground deformation measurement via Differential Interferometric SAR (DInSAR) techniques is performed by IREA-CNR. The selected test sites are Etna, Vesuvius and Campi Flegrei caldera. In particular, ground deformation time series will be generated by using ERS and ENVISAT SAR data and via the application of the Small BAeline Subset (SBAS) technique. This algorithm has the advantage of being both simple and very effective; moreover, it allows an easy combination of multiplatform data, provided that the acquisition geometries of both platform are compatible. In this paper the first results obtained by means of modules developed within the ASI-SRV project and dedicated to the processing of EO historical series are presented.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guy Cerimele
2011-09-30
This Preliminary Public Design Report consolidates for public use nonproprietary design information on the Mountaineer Commercial Scale Carbon Capture & Storage project. The report is based on the preliminary design information developed during the Phase I - Project Definition Phase, spanning the time period of February 1, 2010 through September 30, 2011. The report includes descriptions and/or discussions for: (1) DOE's Clean Coal Power Initiative, overall project & Phase I objectives, and the historical evolution of DOE and American Electric Power (AEP) sponsored projects leading to the current project; (2) Alstom's Chilled Ammonia Process (CAP) carbon capture retrofit technology andmore » the carbon storage and monitoring system; (3) AEP's retrofit approach in terms of plant operational and integration philosophy; (4) The process island equipment and balance of plant systems for the CAP technology; (5) The carbon storage system, addressing injection wells, monitoring wells, system monitoring and controls logic philosophy; (6) Overall project estimate that includes the overnight cost estimate, cost escalation for future year expenditures, and major project risks that factored into the development of the risk based contingency; and (7) AEP's decision to suspend further work on the project at the end of Phase I, notwithstanding its assessment that the Alstom CAP technology is ready for commercial demonstration at the intended scale.« less
Converging Redundant Sensor Network Information for Improved Building Control
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dale Tiller; D. Phil; Gregor Henze
2007-09-30
This project investigated the development and application of sensor networks to enhance building energy management and security. Commercial, industrial and residential buildings often incorporate systems used to determine occupancy, but current sensor technology and control algorithms limit the effectiveness of these systems. For example, most of these systems rely on single monitoring points to detect occupancy, when more than one monitoring point could improve system performance. Phase I of the project focused on instrumentation and data collection. During the initial project phase, a new occupancy detection system was developed, commissioned and installed in a sample of private offices and open-planmore » office workstations. Data acquisition systems were developed and deployed to collect data on space occupancy profiles. Phase II of the project demonstrated that a network of several sensors provides a more accurate measure of occupancy than is possible using systems based on single monitoring points. This phase also established that analysis algorithms could be applied to the sensor network data stream to improve the accuracy of system performance in energy management and security applications. In Phase III of the project, the sensor network from Phase I was complemented by a control strategy developed based on the results from the first two project phases: this controller was implemented in a small sample of work areas, and applied to lighting control. Two additional technologies were developed in the course of completing the project. A prototype web-based display that portrays the current status of each detector in a sensor network monitoring building occupancy was designed and implemented. A new capability that enables occupancy sensors in a sensor network to dynamically set the 'time delay' interval based on ongoing occupant behavior in the space was also designed and implemented.« less
Phase retrieval with the reverse projection method in the presence of object's scattering
NASA Astrophysics Data System (ADS)
Wang, Zhili; Gao, Kun; Wang, Dajiang
2017-08-01
X-ray grating interferometry can provide substantially increased contrast over traditional attenuation-based techniques in biomedical applications, and therefore novel and complementary information. Recently, special attention has been paid to quantitative phase retrieval in X-ray grating interferometry, which is mandatory to perform phase tomography, to achieve material identification, etc. An innovative approach, dubbed ;Reverse Projection; (RP), has been developed for quantitative phase retrieval. The RP method abandons grating scanning completely, and is thus advantageous in terms of higher efficiency and reduced radiation damage. Therefore, it is expected that this novel method would find its potential in preclinical and clinical implementations. Strictly speaking, the reverse projection method is applicable for objects exhibiting only absorption and refraction. In this contribution, we discuss the phase retrieval with the reverse projection method for general objects with absorption, refraction and scattering simultaneously. Especially, we investigate the influence of the object's scattering on the retrieved refraction signal. Both theoretical analysis and numerical experiments are performed. The results show that the retrieved refraction signal is the product of object's refraction and scattering signals for small values. In the case of a strong scattering, the reverse projection method cannot provide reliable phase retrieval. Those presented results will guide the use of the reverse projection method for future practical applications, and help to explain some possible artifacts in the retrieved images and/or reconstructed slices.
NASA Astrophysics Data System (ADS)
Frankowski, G.; Hainich, R.
2009-02-01
Since the mid-eighties, a fundamental idea for achieving measuring accuracy in projected fringe technology was to consider the projected fringe pattern as an interferogram and evaluate it on the basis of advanced algorithms widely used for phase measuring in real-time interferometry. A fundamental requirement for obtaining a sufficiently high degree of measuring accuracy with this so-called "phase measuring projected fringe technology" is that the projected fringes, analogous to interference fringes, must have a cos2-shaped intensity distribution. Until the mid-nineties, this requirement for the projected fringe pattern measurement technology presented a basic handicap for its wide application in 3D metrology. This situation changed abruptly, when in the nineties Texas Instruments introduced to the market advanced digital light projection on the basis of micro mirror based projection systems, socalled DLP technology, which also facilitated the generation and projection of cos2-shaped intensity and/or fringe patterns. With this DLP technology, which from its original approach was actually oriented towards completely different applications such as multimedia projection, Texas Instruments boosted phase-measuring fringe projection in optical 3D metrology to a worldwide breakthrough both for medical as well as industrial applications. A subject matter of the lecture will be to present the fundamental principles and the resulting advantages of optical 3D metrology based on phase-measuring fringe projection using DLP technology. Further will be presented and discussed applications of the measurement technology in medical engineering and industrial metrology.
Downscaled projections of Caribbean coral bleaching that can inform conservation planning.
van Hooidonk, Ruben; Maynard, Jeffrey Allen; Liu, Yanyun; Lee, Sang-Ki
2015-09-01
Projections of climate change impacts on coral reefs produced at the coarse resolution (~1°) of Global Climate Models (GCMs) have informed debate but have not helped target local management actions. Here, projections of the onset of annual coral bleaching conditions in the Caribbean under Representative Concentration Pathway (RCP) 8.5 are produced using an ensemble of 33 Coupled Model Intercomparison Project phase-5 models and via dynamical and statistical downscaling. A high-resolution (~11 km) regional ocean model (MOM4.1) is used for the dynamical downscaling. For statistical downscaling, sea surface temperature (SST) means and annual cycles in all the GCMs are replaced with observed data from the ~4-km NOAA Pathfinder SST dataset. Spatial patterns in all three projections are broadly similar; the average year for the onset of annual severe bleaching is 2040-2043 for all projections. However, downscaled projections show many locations where the onset of annual severe bleaching (ASB) varies 10 or more years within a single GCM grid cell. Managers in locations where this applies (e.g., Florida, Turks and Caicos, Puerto Rico, and the Dominican Republic, among others) can identify locations that represent relative albeit temporary refugia. Both downscaled projections are different for the Bahamas compared to the GCM projections. The dynamically downscaled projections suggest an earlier onset of ASB linked to projected changes in regional currents, a feature not resolved in GCMs. This result demonstrates the value of dynamical downscaling for this application and means statistically downscaled projections have to be interpreted with caution. However, aside from west of Andros Island, the projections for the two types of downscaling are mostly aligned; projected onset of ASB is within ±10 years for 72% of the reef locations. © 2015 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.
NASA Technical Reports Server (NTRS)
vanDam, C. P.; Los, S. M.; Miley, S. J.; Yip, L. P.; Banks, D. W.; Roback, V. E.; Bertelrud, A.
1995-01-01
Flight experiments on NASA Langley's B737-100 (TSRV) airplane have been conducted to document flow characteristics in order to further the understanding of high-lift flow physics, and to correlate and validate computational predictions and wind-tunnel measurements. The project is a cooperative effort involving NASA, industry, and universities. In addition to focusing on in-flight measurements, the project includes extensive application of various computational techniques, and correlation of flight data with computational results and wind-tunnel measurements. Results obtained in the most recent phase of flight experiments are analyzed and presented in this paper. In-flight measurements include surface pressure distributions, measured using flush pressure taps and pressure belts on the slats, main element, and flap elements; surface shear stresses, measured using Preston tubes; off-surface velocity distributions, measured using shear-layer rakes; aeroelastic deformations of the flap elements, measured using an optical positioning system; and boundary-layer transition phenomena, measured using hot-film anemometers and an infrared imaging system. The analysis in this paper primarily focuses on changes in the boundary-layer state that occurred on the slats, main element, and fore flap as a result of changes in flap setting and/or flight condition. Following a detailed description of the experiment, the boundary-layer state phenomenon will be discussed based on data measured during these recent flight experiments.
The Atlanta Supersites project is the first of two Supersites projects to be established during Phase I of EPA's Supersites Program; Phase II is being established through a Request for Assistance. The other initial project is in Fresno, California. The Supersites Program is par...
Vertical amplitude phase structure of a low-frequency acoustic field in shallow water
NASA Astrophysics Data System (ADS)
Kuznetsov, G. N.; Lebedev, O. V.; Stepanov, A. N.
2016-11-01
We obtain in integral and analytic form the relations for calculating the amplitude and phase characteristics of an interference structure of orthogonal projections of the oscillation velocity vector in shallow water. For different frequencies and receiver depths, we numerically study the source depth dependences of the effective phase velocities of an equivalent plane wave, the orthogonal projections of the sound pressure phase gradient, and the projections of the oscillation velocity vector. We establish that at low frequencies in zones of interference maxima, independently of source depth, weakly varying effective phase velocity values are observed, which exceed the sound velocity in water by 5-12%. We show that the angles of arrival of the equivalent plane wave and the oscillation velocity vector in the general case differ; however, they virtually coincide in the zone of the interference maximum of the sound pressure under the condition that the horizontal projections of the oscillation velocity appreciably exceed the value of the vertical projection. We give recommendations on using the sound field characteristics in zones with maximum values for solving rangefinding and signal-detection problems.
This Small Business Innovation Research (SBIR) Phase II project will employ the large scale; highly reliable boron-doped ultrananocrystalline diamond (BD-UNCD®) electrodes developed during Phase I project to build and test Electrochemical Anodic Oxidation process (EAOP)...
Burn Injuries: Causes, Consequences, Knowledge, Behaviors.
ERIC Educational Resources Information Center
Healer, Cheryl V.; And Others
This report covers Phase I of the Burn Injury Education Demonstration Project, a four-phased project designed to explore the feasibility of using educational intervention strategies to increase knowledge and appropriate behaviors and attitudes to reduce the number and severity of burns. Phase I involved a comprehensive needs assessment conducted…
Commercial Art. Project Report Phase I with Research Findings.
ERIC Educational Resources Information Center
Brown, Ted; Sappe', Hoyt
This report provides results of Phase I of a project that researched the occupational area of commercial art, established appropriate committees, and conducted task verification. These results are intended to guide development of a program designed to train commercial artists. Section 1 contains general information: purpose of Phase I; description…
REDUCTION OF USE OF PETROLEUM ENERGY RESOURCES BY CONVERSION OF WASTE COOKING OILS INTO DIESEL FUEL
This project has a dual objective of providing hands-on experience to undergraduate engineering students and producing biodiesel fuel from a used cooking oil feedstock. The project consists of three phases: Phase I - process development and construction of a pilot plant; Phase...
Shao, Hongbo; Ray, Jessica R; Jun, Young-Shin
2011-02-15
To ensure the viability of geologic CO2 sequestration (GCS), we need a holistic understanding of reactions at supercritical CO2 (scCO2)-saline water-rock interfaces and the environmental factors affecting these interactions. This research investigated the effects of salinity and the extent of water on the dissolution and surface morphological changes of phlogopite [KMg2.87Si3.07Al1.23O10(F,OH)2], a model clay mineral in potential GCS sites. Salinity enhanced the dissolution of phlogopite and affected the location, shape, size, and phase of secondary minerals. In low salinity solutions, nanoscale particles of secondary minerals formed much faster, and there were more nanoparticles than in high salinity solutions. The effect of water extent was investigated by comparing scCO2-H2O(g)-phlogopite and scCO2-H2O(l)-phlogopite interactions. Experimental results suggested that the presence of a thin water film adsorbed on the phlogopite surface caused the formation of dissolution pits and a surface coating of secondary mineral phases that could change the physical properties of rocks. These results provide new information for understanding reactions at scCO2-saline water-rock interfaces in deep saline aquifers and will help design secure and environmentally sustainable CO2 sequestration projects.
ERIC Educational Resources Information Center
Cook, Desmond L.; And Others
This memorandum reports on the third phase, the design, of a four-phase project to design project management training materials for local educational agencies. The first section of the memorandum explains some considerations regarding management education and the organization of the report. Section 2 presents the design specifications for the…
ERIC Educational Resources Information Center
BREGZIS, RITVARS
THE PRINCIPAL GOAL OF THE PROJECT IS THE ACTIVATION OF A REAL- TIME MEDICAL LITERATURE SYSTEM, WITH THE CONCEPT FOR THE PROJECT BASED ON RECENT TECHNOLOGICAL INNOVATIONS AND AN APPRAISAL OF EXPECTED FUTURE INFORMATION SYSTEMS. DURING THE FIRST PHASE, A DATA FILE HAS BEEN CREATED WHICH, WITH SOME ADJUSTMENTS, CAN BE EMPLOYED FOR TIME-SHARED…
Phase 2: Array automated assembly task low cost silicon solar array project
NASA Technical Reports Server (NTRS)
Jones, G. T.
1979-01-01
Several microwave systems for use in solar cell fabrication were developed and experimentally tested. The first system used a standing wave rectangular waveguide horn applicator. Satisfactory results were achieved with this system for impedance matching and wafer surface heating uniformity. The second system utilized a resonant TM sub 011 mode cylindrical cavity but could not be employed due to its poor energy coupling efficiency. The third and fourth microwave systems utilized a circular waveguide operating in the TM sub 01 and TM sub 11 but had problems with impedance matching, efficiency, and field uniformity.
Development assessment of wash water reclamation
NASA Technical Reports Server (NTRS)
Putnam, D. F.
1976-01-01
An analytical study assessment of state-of-the-art wash water reclamation technology is presented. It covers all non-phase-change unit operations, unit processes and subsystems currently under development by NASA. Each approach to wash water reclamation is described in detail. Performance data are given together with the projected weights and sizes of key components and subsystems. It is concluded that a simple multifiltration subsystem composed of surface-type cartridge filters, carbon adsorption and ion exchange resins is the most attractive approach for spacecraft wash water reclamation in earth orbital missions of up to 10 years in duration.
Blind color isolation for color-channel-based fringe pattern profilometry using digital projection
NASA Astrophysics Data System (ADS)
Hu, Yingsong; Xi, Jiangtao; Chicharo, Joe; Yang, Zongkai
2007-08-01
We present an algorithm for estimating the color demixing matrix based on the color fringe patterns captured from the reference plane or the surface of the object. The advantage of this algorithm is that it is a blind approach to calculating the demixing matrix in the sense that no extra images are required for color calibration before performing profile measurement. Simulation and experimental results convince us that the proposed algorithm can significantly reduce the influence of the color cross talk and at the same time improve the measurement accuracy of the color-channel-based phase-shifting profilometry.
Individualized Inservice Teacher Education (Project In-Step). Evaluation Report. Phase III.
ERIC Educational Resources Information Center
Thurber, John C.
This is a report on the third phase of Project IN-STEP, which was intended to develop a viable model for individualized, multi-media in-service teacher education programs. (Phase I and II are reported in ED 033 905, and ED 042 709). The rationale for Phase III was to see if the model could be successfully transferred to an area other than teaching…
Wake Cycle Robustness of the Mars Science Laboratory Flight Software
NASA Technical Reports Server (NTRS)
Whitehill, Robert
2011-01-01
The Mars Science Laboratory (MSL) is a spacecraft being developed by the Jet Propulsion Laboratory (JPL) for the purpose of in-situ exploration on the surface of Mars. The objective of MSL is to explore and quantitatively assess a local region on the Martian surface as a habitat for microbial life, past or present. This objective will be accomplished through the assessment of the biological potential of at least one target environment, the characterization of the geology and geochemistry of the landing region, an investigation of the planetary process relevant to past habitability, and a characterization of surface radiation. For this purpose, MSL incorporates a total of ten scientific instruments for which functions are to include, among others, atmospheric and descent imaging, chemical composition analysis, and radiation measurement. The Flight Software (FSW) system is responsible for all mission phases, including launch, cruise, entry-descent-landing, and surface operation of the rover. Because of the essential nature of flight software to project success, each of the software modules is undergoing extensive testing to identify and correct errors.
Some regularity on how to locate electrodes for higher fECG SNRs
NASA Astrophysics Data System (ADS)
Zhang, Jie-Min; Huang, Xiao-Lin; Guan, Qun; Liu, Tie-Bing; Li, Ping; Zhao, Ying; Liu, Hong-Xing
2015-03-01
The electrocardiogram (ECG) recorded from the abdominal surface of a pregnant woman is a composite of maternal ECG, fetal ECG (fECG) and other noises, while only the fECG component is always needed by us. With different locations of electrode pairs on the maternal abdominal surface to measure fECGs, the signal-to-noise ratios (SNRs) of the recorded abdominal ECGs are also correspondingly different. Some regularity on how to locate electrodes to obtain higher fECG SNRs is needed practically. In this paper, 343 groups of abdominal ECG records were acquired from 78 pregnant women with different electrode pairs locating, and an appropriate extended research database is formed. Then the regularity on fECG SNRs corresponding to different electrode pairs locating was studied. Based on statistical analysis, it is shown that the fECG SNRs are significantly higher in certain locations than others. Reasonable explanation is also provided to the statistical result using the theories of the fetal cardiac electrical axis and the signal phase delay. Project supported by the National Natural Science Foundation of China (Grant No. 61271079) and the Supporting Plan Project of Jiangsu Province, China (Grant No. BE2010720).
Simulating industrial plasma reactors - A fresh perspective
NASA Astrophysics Data System (ADS)
Mohr, Sebastian; Rahimi, Sara; Tennyson, Jonathan; Ansell, Oliver; Patel, Jash
2016-09-01
A key goal of the presented research project PowerBase is to produce new integration schemes which enable the manufacturability of 3D integrated power smart systems with high precision TSV etched features. The necessary high aspect ratio etch is performed via the BOSCH process. Investigations in industrial research are often use trial and improvement experimental methods. Simulations provide an alternative way to study the influence of external parameters on the final product, whilst also giving insights into the physical processes. This presentation investigates the process of simulating an industrial ICP reactor used over high power (up to 2x5 kW) and pressure (up to 200 mTorr) ranges, analysing the specific procedures to achieve a compromise between physical correctness and computational speed, while testing commonly made assumptions. This includes, for example, the effect of different physical models and the inclusion of different gas phase and surface reactions with the aim of accurately predicting the dependence of surface rates and profiles on external parameters in SF6 and C4F8 discharges. This project has received funding from the Electronic Component Systems for European Leadership Joint Undertaking under Grant Agreement No. 662133 PowerBase.
NASA Astrophysics Data System (ADS)
Park, Byung Jun; Won, Youngjae; Kim, Byungyeon; Lee, Seungrag
2016-03-01
We have studied the RBC membrane properties between a normal RBC and a RBC in Paroxysrnal nocturnal hemoglobinuria (PNH) patient using common path interferometric quantitative phase microscopy (CPIQPM). CPIQPM system has provided the subnanometer optical path length sensitivity on a millisecond. We have measured the dynamic thickness fluctuations of a normal RBC membrane and a RBC membrane in PNH patient over the whole cell surface with CPIQPM. PNH is a rare and serious disease of blood featured by destruction of red blood cells (RBCs). This destruction happens since RBCs show the defect of protein which protects RBCs from the immune system. We have applied CPIQPM to study the characteristic of RBC membrane in PNH patient. We have shown the morphological shape, volume, and projected surface for both different RBC types. The results have showed both RBCs had the similar shape with donut, but membrane fluctuations in PNH patient was shown to reveal the difference of temporal properties compared with a normal RBC. In order to demonstrate the practical tool of the CPIQPM technique, we have also obtained the time series thickness fluctuation outside a cell.
Toward understanding the roaming mechanism in H + MgH → Mg + HH reaction
Mauguiere, Frederic A. L.; Collins, Peter; Stamatiadis, Stamatis; ...
2016-02-26
The roaming mechanism in the reaction H + MgH →Mg + HH is investigated by classical and quantum dynamics employing an accurate ab initio threedimensional ground electronic state potential energy surface. The reaction dynamics are explored by running trajectories initialized on a four-dimensional dividing surface anchored on three-dimensional normally hyperbolic invariant manifold associated with a family of unstable orbiting periodic orbits in the entrance channel of the reaction (H + MgH). By locating periodic orbits localized in the HMgH well or involving H orbiting around the MgH diatom, and following their continuation with the total energy, regions in phase spacemore » where reactive or nonreactive trajectories may be trapped are found. In this way roaming reaction pathways are deduced in phase space. Patterns similar to periodic orbits projected into configuration space are found for the quantum bound and resonance eigenstates. Roaming is attributed to the capture of the trajectories in the neighborhood of certain periodic orbits. As a result, the complex forming trajectories in the HMgH well can either return to the radical channel or “roam” to the MgHH minimum from where the molecule may react.« less
Fermionic spin liquid analysis of the paramagnetic state in volborthite
NASA Astrophysics Data System (ADS)
Chern, Li Ern; Schaffer, Robert; Sorn, Sopheak; Kim, Yong Baek
2017-10-01
Recently, thermal Hall effect has been observed in the paramagnetic state of volborthite, which consists of distorted kagome layers with S =1 /2 local moments. Despite the appearance of magnetic order below 1 K , the response to external magnetic field and unusual properties of the paramagnetic state above 1 K suggest possible realization of exotic quantum phases. Motivated by these discoveries, we investigate possible spin liquid phases with fermionic spinon excitations in a nonsymmorphic version of the kagome lattice, which belongs to the two-dimensional crystallographic group p 2 g g . This nonsymmorphic structure is consistent with the spin model obtained in the density functional theory calculation. Using projective symmetry group analysis and fermionic parton mean field theory, we identify twelve distinct Z2 spin liquid states, four of which are found to have correspondence in the eight Schwinger boson spin liquid states we classified earlier. We focus on the four fermionic states with bosonic counterpart and find that the spectrum of their corresponding root U (1 ) states features spinon Fermi surface. The existence of spinon Fermi surface in candidate spin liquid states may offer a possible explanation of the finite thermal Hall conductivity observed in volborthite.
NASA Astrophysics Data System (ADS)
Lee, Hyun-Chul; Kumar, Arun; Wang, Wanqiu
2018-03-01
Coupled prediction systems for seasonal and inter-annual variability in the tropical Pacific are initialized from ocean analyses. In ocean initial states, small scale perturbations are inevitably smoothed or distorted by the observational limits and data assimilation procedures, which tends to induce potential ocean initial errors for the El Nino-Southern Oscillation (ENSO) prediction. Here, the evolution and effects of ocean initial errors from the small scale perturbation on the developing phase of ENSO are investigated by an ensemble of coupled model predictions. Results show that the ocean initial errors at the thermocline in the western tropical Pacific grow rapidly to project on the first mode of equatorial Kelvin wave and propagate to the east along the thermocline. In boreal spring when the surface buoyancy flux weakens in the eastern tropical Pacific, the subsurface errors influence sea surface temperature variability and would account for the seasonal dependence of prediction skill in the NINO3 region. It is concluded that the ENSO prediction in the eastern tropical Pacific after boreal spring can be improved by increasing the observational accuracy of subsurface ocean initial states in the western tropical Pacific.