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Sample records for range component directional

  1. Direct qualification of digital components

    SciTech Connect

    Lawrence, J. D., LLNL

    1998-07-08

    Existing methods for qualifying digital system software for use in safety critical systems are expensive and are based on inferences that are of doubtful validity. This report on work-in-progress describes a new approach to qualifying a class of small safety systems that can meet a number of design restrictions, where the restrictions are carefully crafted to permit safety qualification to be determined by means of static analysis of the software combined with a limited amount of testing. This approach differs from attempts to qualify unrestricted programs in the general case. Work that has been accomplished towards this goal is discussed in summary terms. The technique relies on transforming a program into a form of directed graph known as a flowgraph. Existing testing theory is used, sometimes with minor modifications, to derive a set of design restrictions that permit reasoning about safety properties of the program, based on analysis and limited testing. Future work required to complete the research is outlined.

  2. Giant components in directed multiplex networks.

    PubMed

    Azimi-Tafreshi, N; Dorogovtsev, S N; Mendes, J F F

    2014-11-01

    We describe the complex global structure of giant components in directed multiplex networks that generalizes the well-known bow-tie structure, generic for ordinary directed networks. By definition, a directed multiplex network contains vertices of one type and directed edges of m different types. In directed multiplex networks, we distinguish a set of different giant components based on the existence of directed paths of different types between their vertices such that for each type of edges, the paths run entirely through only edges of that type. If, in particular, m=2, we define a strongly viable component as a set of vertices in which for each type of edges each two vertices are interconnected by at least two directed paths in both directions, running through the edges of only this type. We show that in this case, a directed multiplex network contains in total nine different giant components including the strongly viable component. In general, the total number of giant components is 3^{m}. For uncorrelated directed multiplex networks, we obtain exactly the size and the emergence point of the strongly viable component and estimate the sizes of other giant components. PMID:25493836

  3. Giant components in directed multiplex networks

    NASA Astrophysics Data System (ADS)

    Azimi-Tafreshi, N.; Dorogovtsev, S. N.; Mendes, J. F. F.

    2014-11-01

    We describe the complex global structure of giant components in directed multiplex networks that generalizes the well-known bow-tie structure, generic for ordinary directed networks. By definition, a directed multiplex network contains vertices of one type and directed edges of m different types. In directed multiplex networks, we distinguish a set of different giant components based on the existence of directed paths of different types between their vertices such that for each type of edges, the paths run entirely through only edges of that type. If, in particular, m =2 , we define a strongly viable component as a set of vertices in which for each type of edges each two vertices are interconnected by at least two directed paths in both directions, running through the edges of only this type. We show that in this case, a directed multiplex network contains in total nine different giant components including the strongly viable component. In general, the total number of giant components is 3m. For uncorrelated directed multiplex networks, we obtain exactly the size and the emergence point of the strongly viable component and estimate the sizes of other giant components.

  4. Pantaloon Hernia: Obstructed Indirect Component and Direct Component with Cryptorchidism.

    PubMed

    Kariappa, Mohan Kumar; Harihar, Vivek; Kothudum, Ashwini Rajareddy; Hiremath, Vivekanand Kedarlingayya

    2016-01-01

    Cryptorchidism is a condition in which one or both testes have not passed down into the scrotal sac. It is categorized as true undescended testis in which testes are present in the normal path of descent, and as ectopic testis, in which testes are present at abnormal site. Common complications of cryptorchidism are testicular torsion, subfertility, inguinal hernia, and testicular cancer. Here we present a rare case of pantaloon hernia of obstructed indirect component and direct component with cryptorchidism. PMID:27579208

  5. Pantaloon Hernia: Obstructed Indirect Component and Direct Component with Cryptorchidism

    PubMed Central

    Kariappa, Mohan Kumar; Hiremath, Vivekanand Kedarlingayya

    2016-01-01

    Cryptorchidism is a condition in which one or both testes have not passed down into the scrotal sac. It is categorized as true undescended testis in which testes are present in the normal path of descent, and as ectopic testis, in which testes are present at abnormal site. Common complications of cryptorchidism are testicular torsion, subfertility, inguinal hernia, and testicular cancer. Here we present a rare case of pantaloon hernia of obstructed indirect component and direct component with cryptorchidism. PMID:27579208

  6. Development of a 6-component balance for the cryogenic range

    NASA Astrophysics Data System (ADS)

    Graewe, E.

    1984-06-01

    Criteria for wind tunnel strain gage component balances applicable in the temperature range 100 to 300 K were derived. An unheated six-component balance was constructed and examined. With the corresponding software this balance is practibable on quasi stationary temperatures in the range 100 to 300 K.

  7. Directed light fabrication of rhenium components

    SciTech Connect

    Milewski, J.O.; Thoma, D.J.; Lewis, G.K.

    1997-02-01

    Directed Light Fabrication (DLF) is a direct metal deposition process that fuses powder, delivered by gas into the focal zone of a high powered laser beam to form fully dense near-net shaped components. This is accomplished in one step without the use of molds, dies, forming, pressing, sintering or forging equipment. DLF is performed in a high purity inert environment free from the contaminants associated with conventional processing such as oxide and carbon pickup, lubricants, binding agents, cooling or cleaning agents. Applications using rhenium have historically been limited in part by its workability and cost. This study demonstrates the ability to fuse rhenium metal powder, using a DLF machine, into free standing rods and describes the associated parameter study. Microstructural comparisons between DLF deposited rhenium and commercial rhenium sheet product is performed. This research combined with existing DLF technology demonstrates the feasibility of forming complex rhenium, metal shapes directly from powder.

  8. Programmable, directed assembly of micron-scale components

    NASA Astrophysics Data System (ADS)

    Floryan, Caspar; Westervelt, Robert

    2011-03-01

    Self assembly is a nascent paradigm for assembling components in the micron to millimeter size range. Such assemblies are often performed by modifying the surface chemistries of the individual components or by creating flow fields directing them into position. We propose a method of directed assembly using dielectric contrast between the components and a surrounding fluid. A hybrid integrated-circuit / microfluidic device will be used to trap and manipulate pieces into pre-defined patterns. The device contains an array of electrically-chargeable pixels on its surface, with a resolution of 10 μ m. Thomas Hunt, David Issadore, Robert Westervelt ``Integrated Circuit/Microfluidic Chip to Programmably Trap and Move Cells and Droplets with Dielectrophoresis'' Lab on a Chip 8, 81-87 (2008)

  9. Direct-write diffracting tubular optical components using femtosecond lasers

    NASA Astrophysics Data System (ADS)

    McMillen, Ben; Bellouard, Yves

    2014-03-01

    Over the last decade, femtosecond lasers have been used extensively for the fabrication of optical elements via direct writing and in combination with chemical etching. These processes have been an enabling technology for manufacturing a variety of devices such as waveguides, fluidic channels, and mechanical components. Here, we present high quality micro-scale optical components buried inside various glass substrates such as soda-lime glass or fused silica. These components consist of high-precision, simple patterns with tubular shapes. Typical diameters range from a few microns to one hundred microns. With the aid of high-bandwidth, high acceleration flexure stages, we achieve highly symmetric pattern geometries, which are particularly important for achieving homogeneous stress distribution within the substrate. We model the optical properties of these structures using beam propagation simulation techniques and experimentally demonstrate that such components can be used as cost-effective, low-numerical aperture lenses. Additionally, we investigate their capability for studying the stress-distribution induced by the laser-affected zones and possible related densification effects.

  10. Ratchetaxis: Long-Range Directed Cell Migration by Local Cues.

    PubMed

    Caballero, David; Comelles, Jordi; Piel, Matthieu; Voituriez, Raphaël; Riveline, Daniel

    2015-12-01

    Directed cell migration is usually thought to depend on the presence of long-range gradients of either chemoattractants or physical properties such as stiffness or adhesion. However, in vivo, chemical or mechanical gradients have not systematically been observed. Here we review recent in vitro experiments, which show that other types of spatial guidance cues can bias cell motility. Introducing local geometrical or mechanical anisotropy in the cell environment, such as adhesive/topographical microratchets or tilted micropillars, show that local and periodic external cues can direct cell motion. Together with modeling, these experiments suggest that cell motility can be viewed as a stochastic phenomenon, which can be biased by various types of local cues, leading to directional migration. PMID:26615123

  11. Theoretical antineutrino detection, direction and ranging at long distances

    NASA Astrophysics Data System (ADS)

    Jocher, Glenn R.; Bondy, Daniel A.; Dobbs, Brian M.; Dye, Stephen T.; Georges, James A.; Learned, John G.; Mulliss, Christopher L.; Usman, Shawn

    2013-06-01

    In this paper we introduce the concept of what we call “NUDAR” (NeUtrino Direction and Ranging), making the point that measurements of the observed energy and direction vectors can be employed to passively deduce the exact three-dimensional location and thermal power of geophysical and anthropogenic neutrino sources from even a single detector. Earlier studies have presented the challenges of long-range detection, dominated by the unavoidable inverse-square falloff in neutrinos, which force the use of kiloton scale detectors beyond a few kilometers. Earlier work has also presented the case for multiple detectors, and has reviewed the background challenges. We present the most precise background estimates to date, all handled in full three dimensions, as functions of depth and geographical location. For the present calculations, we consider a hypothetical 138 kiloton detector which can be transported to an ocean site and deployed to an operational depth. We present a Bayesian estimation framework to incorporate any a priori knowledge of the reactor that we are trying to detect, as well as the estimated uncertainty in the background and the oscillation parameters. Most importantly, we fully employ the knowledge of the reactor spectrum and the distance-dependent effects of neutrino oscillations on such spectra. The latter, in particular, makes possible determination of range from one location, given adequate signal statistics. Further, we explore the rich potential of improving detection with even modest improvements in individual neutrino direction determination. We conclude that a 300 MWth reactor can indeed be geolocated, and its operating power estimated with one or two detectors in the hundred kiloton class at ranges out to a few hundred kilometers. We note that such detectors would have natural and non-interfering utility for scientific studies of geo-neutrinos, neutrino oscillations, and astrophysical neutrinos. This motivates the development of cost

  12. Rectified directional sensing in long-range cell migration

    PubMed Central

    Nakajima, Akihiko; Ishihara, Shuji; Imoto, Daisuke; Sawai, Satoshi

    2014-01-01

    How spatial and temporal information are integrated to determine the direction of cell migration remains poorly understood. Here, by precise microfluidics emulation of dynamic chemoattractant waves, we demonstrate that, in Dictyostelium, directional movement as well as activation of small guanosine triphosphatase Ras at the leading edge is suppressed when the chemoattractant concentration is decreasing over time. This ‘rectification’ of directional sensing occurs only at an intermediate range of wave speed and does not require phosphoinositide-3-kinase or F-actin. From modelling analysis, we show that rectification arises naturally in a single-layered incoherent feedforward circuit with zero-order ultrasensitivity. The required stimulus time-window predicts ~5 s transient for directional sensing response close to Ras activation and inhibitor diffusion typical for protein in the cytosol. We suggest that the ability of Dictyostelium cells to move only in the wavefront is closely associated with rectification of adaptive response combined with local activation and global inhibition. PMID:25373620

  13. Ionoacoustics: A new direct method for range verification

    NASA Astrophysics Data System (ADS)

    Parodi, Katia; Assmann, Walter

    2015-05-01

    The superior ballistic properties of ion beams may offer improved tumor-dose conformality and unprecedented sparing of organs at risk in comparison to other radiation modalities in external radiotherapy. However, these advantages come at the expense of increased sensitivity to uncertainties in the actual treatment delivery, resulting from inaccuracies of patient positioning, physiological motion and uncertainties in the knowledge of the ion range in living tissue. In particular, the dosimetric selectivity of ion beams depends on the longitudinal location of the Bragg peak, making in vivo knowledge of the actual beam range the greatest challenge to full clinical exploitation of ion therapy. Nowadays, in vivo range verification techniques, which are already, or close to, being investigated in the clinical practice, rely on the detection of the secondary annihilation photons or prompt gammas, resulting from nuclear interaction of the primary ion beam with the irradiated tissue. Despite the initial promising results, these methods utilize a not straightforward correlation between nuclear and electromagnetic processes, and typically require massive and costly instrumentation. On the contrary, the long-term known, yet only recently revisited process of "ionoacoustics", which is generated by local tissue heating especially at the Bragg peak, may offer a more direct approach to in vivo range verification, as reviewed here.

  14. Direct-write fabrication of integrated, multilayer ceramic components

    SciTech Connect

    Dimos, D.; Yang, P.; Garino, T.J.; Raymond, M.V.; Rodriguez, M.A.

    1997-08-01

    The need for advanced (electronic) ceramic components with smaller size, greater functionality, and enhanced reliability requires the ability to integrate electronic ceramics in complex 3-D architectures. For rapid prototyping and small-lot manufacturing, traditional tape casting and screen printing approaches are poorly suited. To address this need, the authors are developing a direct-write approach for fabricating highly integrated, multilayer components using a micropen to deposit slurries in precise patterns. With this technique, components can be constructed layer by layer, simplifying fabrication. It can also be used to produce structures combining several materials in a single layer. The parts are either cofired or sequentially fired, after each layer is deposited. Since differential shrinkage can lead to defects in these multilayer structures, they are characterizing the sintering behavior of individual layers. This technique has been used to fabricate devices such integrated RC filters, multilayer voltage transformers, and other passive components. The direct-write approach provides the ability to fabricate multifunctional, multimaterial integrated ceramic components (MMICCs) in an agile and rapid way.

  15. Laser engineered net shaping for direct fabrication of metal components

    SciTech Connect

    Dimos, D.; Schlienger, M.E.

    1997-09-01

    Sandia National Laboratories is developing a new technology to fabricate three-dimensional metallic components directly from CAD solid models. This process, called Laser Engineered Net Shaping (LENS{trademark}), exhibits enormous potential to revolutionize the way in which metal parts, such as complex prototypes, tooling, and small lot production parts, are produced. To perform the process, metal powder is injected into a molten pool created by a focused, high powered laser beam. Simultaneously, the substrate on which the deposition is occurring is scanned under the beam/powder interaction zone to fabricate the desired cross-sectional geometry. Consecutive layers are sequentially deposited, thereby producing a three-dimensional metal component.

  16. Automatic and Direct Identification of Blink Components from Scalp EEG

    PubMed Central

    Kong, Wanzeng; Zhou, Zhanpeng; Hu, Sanqing; Zhang, Jianhai; Babiloni, Fabio; Dai, Guojun

    2013-01-01

    Eye blink is an important and inevitable artifact during scalp electroencephalogram (EEG) recording. The main problem in EEG signal processing is how to identify eye blink components automatically with independent component analysis (ICA). Taking into account the fact that the eye blink as an external source has a higher sum of correlation with frontal EEG channels than all other sources due to both its location and significant amplitude, in this paper, we proposed a method based on correlation index and the feature of power distribution to automatically detect eye blink components. Furthermore, we prove mathematically that the correlation between independent components and scalp EEG channels can be translating directly from the mixing matrix of ICA. This helps to simplify calculations and understand the implications of the correlation. The proposed method doesn't need to select a template or thresholds in advance, and it works without simultaneously recording an electrooculography (EOG) reference. The experimental results demonstrate that the proposed method can automatically recognize eye blink components with a high accuracy on entire datasets from 15 subjects. PMID:23959240

  17. Ranging system which compares an object reflected component of a light beam to a reference component of the light beam

    NASA Technical Reports Server (NTRS)

    Mclauchlan, J. M.; Auyeung, J.; Tubbs, E. F.; Goss, W. C.; Psaltis, D. (Inventor)

    1985-01-01

    A system is described for measuring the distance to an object by comparing a first component of a light pulse that is reflected off the object with a second component of the light pulse that passes along a reference path of known length, which provides great accuracy with a relatively simple and rugged design. The reference path can be changed in precise steps so that it has an equivalent length approximately equal to the path length of the light pulse component that is reflected from the object. The resulting small difference in path lengths can be precisely determined by directing the light pulse components into opposite ends of a detector formed of a material that emits a second harmonic light output at the locations where the opposite going pulses past simultaneously across one another.

  18. Direct and Collisional Excitation of Automotive Fuel Components)

    NASA Astrophysics Data System (ADS)

    White, Allen R.; Wilson, Kyle; Sakai, Stephen; Devasher, Rebecca B.

    2010-06-01

    Adding energy directly into the vibrational modes of automotive fuel may reduce the threshold energy required for combustion, without raising the combustion charge temperature. This energy can be supplied either directly via incident laser radiation or indirectly through collision with directly excited molecules. The most common chemical in commercial gasoline, isooctane, does not absorb infrared radiation sufficiently at any wavelength for which an infrared laser is readily available. However, CO2 lasers are relatively cheap, and are available at wavelengths which are absorbed by isopropanol as well as ethanol, which is also a component of commercial gasoline. In this study, the infrared absorption of isopropanol and ethanol in balance isooctane were measured at three wavelengths (10.6 m, 10.2 m, and 9.3 m) of incident CO2 laser radiation. Additional time-resolved emission measurements were performed for these mixtures. The data support the existence of the proposed collisional pathway for energy transfer from ethanol and isopropanol to isooctane.

  19. Weighted Model Components for Gradient Direction Matching in Overhead Images

    SciTech Connect

    Grant, C W; Nikolaev, S; Paglieroni, D W

    2006-03-17

    Gradient direction matching (GDM) is the main target identification algorithm used in the Image Content Engine project at Lawrence Livermore National Laboratory. GDM is a 3D solid model-based edge-matching algorithm which does not require explicit edge extraction from the source image. The GDM algorithm is presented, identifying areas where performance enhancement seems possible. Improving the process of producing model gradient directions from the solid model by assigning different weights to different parts of the model is an extension tested in the current study. Given a simple geometric model, we attempt to determine, without obvious semantic clues, if different weight values produce significantly better matching accuracy, and how those weights should be assigned to produce the best matching accuracy. Two simple candidate strategies for assigning weights are proposed--pixel-weighted and edge-weighted. We adjust the weights of the components in a simple model of a tractor/semi-trailer using relevance feedback to produce an optimal set of weights for this model and a particular test image. The optimal weights are then compared with pixel and edge-weighting strategies to determine which is most suitable and under what circumstances.

  20. Hot isostatic pressing of direct selective laser sintered metal components

    NASA Astrophysics Data System (ADS)

    Wohlert, Martin Steven

    2000-10-01

    A new manufacturing process combining the benefits of Selective Laser Sintering (SLS) and Hot Isostatic Pressing (HIP) has been developed to permit Rapid Prototyping of high performance metal components. The new process uses Direct Metal SLS to produce a gas impermeable HIP container from the same powdered material that will eventually compose the bulk of the part. The SLS generated capsule performs the functions of the sheet metal container in traditional HIP, but unlike a sheet metal container, the SLSed capsule becomes an integral part of the final component. Additionally, SLS can produce a capsule of far greater geometric complexity than can be achieved by sheet metal forming. Two high performance alloys, Ti-6Al-4V and Inconel 625, were selected for use in the development of the new process. HIP maps were constructed to predict the densification rate of the two materials during HIP processing. Comparison to experimentally determined densification behavior indicated that the maps provide a useful qualitative description of densification rates; however, the accuracy of quantitative predictions was greatly enhanced by tuning key material parameters based on a limited number of experimental HIP cycles. Microstructural characterization of SLS + HIP samples revealed two distinct regions within the components. The outer SLS processed capsule material exhibited a relatively coarse microstructure comparable to a cast, or multi-layer welded structure. No layer boundaries were discernible in the SLS material, with grains observed to grow epitaxially from previously deposited material. The microstructure of the HIP consolidated core material was similar to conventionally HIP processed powder materials, featuring a fine grain structure and preserved prior particle boundaries. The large variation in grain size between the capsule and core materials was reflected in hardness measurements conducted on the Alloy 625 material; however, the variation in hardness was less

  1. Direct Measurement of Intermediate-Range Casimir-Polder Potentials

    SciTech Connect

    Bender, H.; Courteille, Ph. W.; Marzok, C.; Zimmermann, C.; Slama, S.

    2010-02-26

    We present the first direct measurements of Casimir-Polder forces between solid surfaces and atomic gases in the transition regime between the electrostatic short-distance and the retarded long-distance limit. The experimental method is based on ultracold ground-state Rb atoms that are reflected from evanescent wave barriers at the surface of a dielectric glass prism. Our novel approach does not require assumptions about the potential shape. The experimental data are compared to the theoretical predictions valid in the different regimes. They agree best with a full QED calculation.

  2. Directed self-assembly of mesoscopic components for led applications

    NASA Astrophysics Data System (ADS)

    Tkachenko, Anton

    Light-emitting diodes (LEDs) constitute a rapidly evolving and fast growing technology that promises to replace incandescent bulbs and compact fluorescent lights in many illumination applications. Large-area LED luminaires have a capability to transform lighting by providing a venue for development of smart lighting systems with additional benefits, such as visible light communications, sensing, health and productivity improvement through color temperature control, capability of creating "virtual sky" ceiling, and many others. The objective of this work is to explore directed self-assembly (DSA) approaches suitable for cost-effective assembly of large amount of LEDs and other mesoscopic (i.e. millimeter and sub-millimeter) electronic components and thus to enable manufacturing of smart lighting luminaires. Existing alternative approaches for assembly of semiconductor dies are examined including transfer printing, laser-assisted die transfer, and various directed self-assembly approaches using shape-recognition, magnetic and capillary forces, etc. After comparing their advantages and limitations, we developed two approaches to magnetic force-assisted DSA of LEDs on a large-area substrate in liquid and air medium. The first approach involves pick-up of buoyant and magnetic dies from the liquid surface onto the flexible substrate in a roll-to-roll process. The possibility of high-speed assembly of LED dies is demonstrated, but with a low yield due to the influence of the capillary force of the carrier liquid and the difficulty in ensuring reliable supply of dies to the assembly interface. To overcome the aforementioned challenges this process was modified to assemble the dies by sinking them onto the receiving substrate with a stencil mask on top, demonstrating LED assembly with a very low error rate but at a lower speed. A solder-assisted self-alignment is used to further improve placement precision and to ensure the proper orientation of the dies. The second

  3. Evaluation of skin melanoma in spectral range 450-950 nm using principal component analysis

    NASA Astrophysics Data System (ADS)

    Jakovels, D.; Lihacova, I.; Kuzmina, I.; Spigulis, J.

    2013-06-01

    Diagnostic potential of principal component analysis (PCA) of multi-spectral imaging data in the wavelength range 450- 950 nm for distant skin melanoma recognition is discussed. Processing of the measured clinical data by means of PCA resulted in clear separation between malignant melanomas and pigmented nevi.

  4. Direct Visualization of Short Transverse Relaxation Time Component (ViSTa)

    PubMed Central

    Oh, Se-Hong; Bilello, Michel; Schindler, Matthew; Markowitz, Clyde E.; Detre, John A.; Lee, Jongho

    2013-01-01

    White matter of the brain has been demonstrated to have multiple relaxation components. Among them, the short transverse relaxation time component (T2 < 40 ms; T2* < 25 ms at 3T) has been suggested to originate from myelin water whereas long transverse relaxation time components have been associated with axonal and/or interstitial water. In myelin water imaging, T2 or T2* signal decay is measured to estimate myelin water fraction based on T2 or T2* differences among the water components. This method has been demonstrated to be sensitive to demyelination in the brain but suffers from low SNR and image artifacts originating from ill-conditioned multi-exponential fitting. In this study, a novel approach that selectively acquires short transverse relaxation time signal is proposed. The method utilizes a double inversion RF pair to suppress a range of long T1 signal. This suppression leaves short T2* signal, which has been suggested to have short T1, as the primary source of the image. The experimental results confirms that after suppression of long T1 signals, the image is dominated by short T2* in the range of myelin water, allowing us to directly visualize the short transverse relaxation time component in the brain. Compared to conventional myelin water imaging, this new method of direct visualization of short relaxation time component (ViSTa) provides high quality images. When applied to multiple sclerosis patients, chronic lesions show significantly reduced signal intensity in ViSTa images suggesting sensitivity to demyelination. PMID:23796545

  5. Enhancement of concentration range of chromatographically detectable components with array detector mass spectrometry

    DOEpatents

    Enke, Christie

    2013-02-19

    Methods and instruments for high dynamic range analysis of sample components are described. A sample is subjected to time-dependent separation, ionized, and the ions dispersed with a constant integration time across an array of detectors according to the ions m/z values. Each of the detectors in the array has a dynamically adjustable gain or a logarithmic response function, producing an instrument capable of detecting a ratio of responses or 4 or more orders of magnitude.

  6. Sizing Power Components of an Electrically Driven Tail Cone Thruster and a Range Extender

    NASA Technical Reports Server (NTRS)

    Jansen, Ralph H.; Bowman, Cheryl; Jankovsky, Amy

    2016-01-01

    The aeronautics industry has been challenged on many fronts to increase efficiency, reduce emissions, and decrease dependency on carbon-based fuels. This paper provides an overview of the turboelectric and hybrid electric technologies being developed under NASA's Advanced Air Transportation Technology (AATT) Project and discusses how these technologies can impact vehicle design. The discussion includes an overview of key hybrid electric studies and technology investments, the approach to making informed investment decisions based on key performance parameters and mission studies, and the power system architectures for two candidate aircraft. Finally, the power components for a single-aisle turboelectric aircraft with an electrically driven tail cone thruster and for a hybrid-electric nine-passenger aircraft with a range extender are parametrically sized, and the sensitivity of these components to key parameters is presented.

  7. Directed intermixing in multi-component self-assembling biomaterials

    PubMed Central

    Gasiorowski, Joshua Z.; Collier, Joel H.

    2011-01-01

    The non-covalent co-assembly of multiple different peptides can be a useful route for producing multifunctional biomaterials. However, to date such materials have almost exclusively been investigated as homogeneous self-assemblies, having functional components uniformly distributed throughout their supramolecular structures. Here we illustrate control over the intermixing of multiple different self-assembling peptides, in turn providing a simple but powerful means for modulating these materials’ mechanical and biological properties. In beta-sheet fibrillizing hydrogels, significant increases in stiffening could be achieved using heterobifunctional cross-linkers by sequestering peptides bearing different reactive groups into distinct populations of fibrils, thus favoring inter-fibril cross-linking. Further, by specifying the intermixing of RGD-bearing peptides in 2-D and 3-D self-assemblies, the growth of HUVECs and NIH 3T3 cells could be significantly modulated. This approach may be immediately applicable towards a wide variety of self-assembling systems that form stable supramolecular structures. PMID:21863894

  8. Interpreting the Geochemistry of the Northern Peninsula Ranges Batholith Using Principle Component Analysis and Spatial Interpolation

    NASA Astrophysics Data System (ADS)

    Pompe, L.; Clausen, B. L.; Morton, D. M.

    2014-12-01

    The Cretaceous northern Peninsular Ranges batholith (PRB) exemplifies emplacement in a combination oceanic arc / continental margin arc setting. Two approaches that can aid in understanding its statistical and spatial geochemistry variation are principle component analysis (PCA) and GIS interpolation mapping. The data analysis primarily used 287 samples from the large granitoid geochemical data set systematically collected by Baird and Welday. Of these, 80 points fell in the western Santa Ana block, 108 in the transitional Perris block, and 99 in the eastern San Jacinto block. In the statistical analysis, multivariate outliers were identified using Mahalanobis distance and excluded. A centered log ratio transformation was used to facilitate working with geochemical concentration values that range over many orders of magnitude. The data was then analyzed using PCA with IBM SPSS 21 reducing 40 geochemical variables to 4 components which are approximately related to the compatible, HFS, HRE, and LIL elements. The 4 components were interpreted as follows: (1) compatible [and negatively correlated incompatible] elements indicate extent of differentiation as typified by SiO2, (2) HFS elements indicate crustal contamination as typified by Sri and Nb/Yb ratios, (3) HRE elements indicate source depth as typified by Sr/Y and Gd/Yb ratios, and (4) LIL elements indicate alkalinity as typified by the K2O/SiO2ratio. Spatial interpolation maps of the 4 components were created with Esri ArcGIS for Desktop 10.2 by interpolating between the sample points using kriging and inverse distance weighting. Across-arc trends on the interpolation maps indicate a general increase from west to east for each of the 4 components, but with local exceptions as follows. The 15km offset on the San Jacinto Fault may be affecting the contours. South of San Jacinto is a west-east band of low Nb/Yb, Gd/Yb, and Sr/Y ratios. The highest Sr/Y ratios in the north central area that decrease further east may

  9. Extracellular matrix components direct porcine muscle stem cell behavior

    SciTech Connect

    Wilschut, Karlijn J.; Haagsman, Henk P.; Roelen, Bernard A.J.

    2010-02-01

    In muscle tissue, extracellular matrix proteins, together with the vasculature system, muscle-residence cells and muscle fibers, create the niche for muscle stem cells. The niche is important in controlling proliferation and directing differentiation of muscle stem cells to sustain muscle tissue. Mimicking the extracellular muscle environment improves tools exploring the behavior of primary muscle cells. Optimizing cell culture conditions to maintain muscle commitment is important in stem cell-based studies concerning toxicology screening, ex vivo skeletal muscle tissue engineering and in the enhancement of clinical efficiency. We used the muscle extracellular matrix proteins collagen type I, fibronectin, laminin, and also gelatin and Matrigel as surface coatings of tissue culture plastic to resemble the muscle extracellular matrix. Several important factors that determine myogenic commitment of the primary muscle cells were characterized by quantitative real-time RT-PCR and immunofluorescence. Adhesion of high PAX7 expressing satellite cells was improved if the cells were cultured on fibronectin or laminin coatings. Cells cultured on Matrigel and laminin coatings showed dominant integrin expression levels and exhibited an activated Wnt pathway. Under these conditions both stem cell proliferation and myogenic differentiation capacity were superior if compared to cells cultured on collagen type I, fibronectin and gelatin. In conclusion, Matrigel and laminin are the preferred coatings to sustain the proliferation and myogenic differentiation capacity of the primary porcine muscle stem cells, when cells are removed from their natural environment for in vitro culture.

  10. Information processing in parallel through directionally resolved molecular polarization components in coherent multidimensional spectroscopy

    NASA Astrophysics Data System (ADS)

    Yan, Tian-Min; Fresch, Barbara; Levine, R. D.; Remacle, F.

    2015-08-01

    We propose that information processing can be implemented by measuring the directional components of the macroscopic polarization of an ensemble of molecules subject to a sequence of laser pulses. We describe the logic operation theoretically and demonstrate it by simulations. The measurement of integrated stimulated emission in different phase matching spatial directions provides a logic decomposition of a function that is the discrete analog of an integral transform. The logic operation is reversible and all the possible outputs are computed in parallel for all sets of possible multivalued inputs. The number of logic variables of the function is the number of laser pulses used in sequence. The logic function that is computed depends on the chosen chromophoric molecular complex and on its interactions with the solvent and on the two time intervals between the three pulses and the pulse strengths and polarizations. The outputs are the homodyne detected values of the polarization components that are measured in the allowed phase matching macroscopic directions, kl, k l = ∑ i l i k i where ki is the propagation direction of the ith pulse and {li} is a set of integers that encodes the multivalued inputs. Parallelism is inherently implemented because all the partial polarizations that define the outputs are processed simultaneously. The outputs, which are read directly on the macroscopic level, can be multivalued because the high dynamical range of partial polarization measurements by nonlinear coherent spectroscopy allows for fine binning of the signals. The outputs are uniquely related to the inputs so that the logic is reversible.

  11. Control range: a controllability-based index for node significance in directed networks

    NASA Astrophysics Data System (ADS)

    Wang, Bingbo; Gao, Lin; Gao, Yong

    2012-04-01

    While a large number of methods for module detection have been developed for undirected networks, it is difficult to adapt them to handle directed networks due to the lack of consensus criteria for measuring the node significance in a directed network. In this paper, we propose a novel structural index, the control range, motivated by recent studies on the structural controllability of large-scale directed networks. The control range of a node quantifies the size of the subnetwork that the node can effectively control. A related index, called the control range similarity, is also introduced to measure the structural similarity between two nodes. When applying the index of control range to several real-world and synthetic directed networks, it is observed that the control range of the nodes is mainly influenced by the network's degree distribution and that nodes with a low degree may have a high control range. We use the index of control range similarity to detect and analyze functional modules in glossary networks and the enzyme-centric network of homo sapiens. Our results, as compared with other approaches to module detection such as modularity optimization algorithm, dynamic algorithm and clique percolation method, indicate that the proposed indices are effective and practical in depicting structural and modular characteristics of sparse directed networks.

  12. Direct Georeferencing with on Board Navigation Components of Light Weight Uav Platforms

    NASA Astrophysics Data System (ADS)

    Pfeifer, N.; Glira, P.; Briese, C.

    2012-08-01

    Unmanned aerial vehicles (UAV) are a promising platform for close range airborne photogrammetry. Next to the possibility of carrying certain sensor equipment, different on board navigation components may be integrated. These devices are getting, due to recent developments in the field of electronics, smaller and smaller and are easily affordable. Therefore, UAV platforms are nowadays often equipped with several navigation devices in order to support the remote control of a UAV. Furthermore, these devices allow an automated flight mode that allows to systematically sense a certain area or object of interest. However, next to their support for the UAV navigation they allow the direct georeferencing of synchronised sensor data. This paper introduces the direct georeferencing of airborne UAV images with a low cost solution based on a quadrocopter. The system is equipped with a Global Navigation Satellite System (GNSS), an Inertial Measurement Unit (IMU), an air pressure sensor, a magnetometer, and a small compact camera. A challenge using light weight consumer-grade sensors is the acquisition of high quality images with respect to brightness and sharpness. It is demonstrated that an appropriate solution for data synchronisation and data processing allows a direct georeferencing of the acquired images with a precision below 1m in each coordinate. The precision for roll and pitch is below 1° and for the yaw it is 2.5°. The evaluation is based on image positions estimated based on the on board sensors and compared to an independent bundle block adjustment of the images.

  13. Preliminary Evaluation of Various Training Components on Accuracy of Direct Behavior Ratings

    ERIC Educational Resources Information Center

    Chafouleas, Sandra M.; Kilgus, Stephen P.; Riley-Tillman, T. Chris; Jaffery, Rose; Harrison, Sayward

    2012-01-01

    This study examined the impact of various components of rater training on the accuracy of rating behavior using Direct Behavior Rating-Single Item Scales (DBR-SIS). Specifically, the addition of frame-of-reference and rater error training components to a standard package involving an overview and then modeling, practice, and feedback was…

  14. Wide-range Vacuum Measurements from MWNT Field Emitters Grown Directly on Stainless Steel Substrates.

    PubMed

    Zhang, Jian; Li, Detian; Zhao, Yangyang; Cheng, Yongjun; Dong, Changkun

    2016-12-01

    The field emission properties and the vacuum measurement application are investigated from the multi-walled carbon nanotubes (MWNTs) grown directly on catalytic stainless steel substrates. The MWNT emitters present excellent emission properties after the acid treatment of the substrate. The MWNT gauge is able to work down to the extreme-high vacuum (XHV) range with linear measurement performance in wide range from 10(-11) to 10(-6) Torr. A modulating grid is attempted with improved gauge sensitivity. The extension of the lower pressure limit is attributed largely to low outgassing effect due to direct growth of MWNTs and justified design of the electron source. PMID:26738501

  15. Wide-range Vacuum Measurements from MWNT Field Emitters Grown Directly on Stainless Steel Substrates

    NASA Astrophysics Data System (ADS)

    Zhang, Jian; Li, Detian; Zhao, Yangyang; Cheng, Yongjun; Dong, Changkun

    2016-01-01

    The field emission properties and the vacuum measurement application are investigated from the multi-walled carbon nanotubes (MWNTs) grown directly on catalytic stainless steel substrates. The MWNT emitters present excellent emission properties after the acid treatment of the substrate. The MWNT gauge is able to work down to the extreme-high vacuum (XHV) range with linear measurement performance in wide range from 10-11 to 10-6 Torr. A modulating grid is attempted with improved gauge sensitivity. The extension of the lower pressure limit is attributed largely to low outgassing effect due to direct growth of MWNTs and justified design of the electron source.

  16. The muscle force component in pedaling retains constant direction across pedaling rates.

    PubMed

    Loras, Havardn; Ettema, Gertjan; Leirdal, Stig

    2009-02-01

    Changes in pedaling rate during cycling have been found to alter the pedal forces. Especially, the force effectiveness is reduced when pedaling rate is elevated. However, previous findings related to the muscular force component indicate strong preferences for certain force directions. Furthermore, inertial forces (due to limb inertia) generated at the pedal increase with elevated pedaling rate. It is not known how pedaling rate alters the inertia component and subsequently force effectiveness. With this in mind, we studied the effect of pedal rate on the direction of the muscle component, quantified with force effectiveness. Cycle kinetics were recorded for ten male competitive cyclists at five cadences (60-100 rpm) during unloaded cycling (to measure inertia) and at a submaximal load (~260 W). The force effectiveness decreased as a response to increased pedaling rate, but subtracting inertia eliminated this effect. This indicates consistent direction of the muscle component of the foot force. PMID:19299833

  17. Emergence of the giant weak component in directed random graphs with arbitrary degree distributions

    NASA Astrophysics Data System (ADS)

    Kryven, Ivan

    2016-07-01

    The weak component generalizes the idea of connected components to directed graphs. In this paper, an exact criterion for the existence of the giant weak component is derived for directed graphs with arbitrary bivariate degree distributions. In addition, we consider a random process for evolving directed graphs with bounded degrees. The bounds are not the same for different vertices but satisfy a predefined distribution. The analytic expression obtained for the evolving degree distribution is then combined with the weak-component criterion to obtain the exact time of the phase transition. The phase-transition time is obtained as a function of the distribution that bounds the degrees. Remarkably, when viewed from the step-polymerization formalism, the new results yield Flory-Stockmayer gelation theory and generalize it to a broader scope.

  18. Future directions for probing two and three nucleon short-range correlations at high energies

    SciTech Connect

    Frankfurt, Leonid; Sargsian, Misak; Strikman, Mark

    2008-10-13

    We summarize recent progress in the studies of the short-rang correlations (SRC) in nuclei in high energy electron and hadron nucleus scattering and suggest directions for the future high energy studies aimed at establishing detailed structure of two-nucleon SRCs, revealing structure of three nucleon SRC correlations and discovering non-nucleonic degrees of freedom in nuclei.

  19. HOTCFGM-2D: A Coupled Higher-Order Theory for Cylindrical Structural Components with Bi-Directionally Components with Bi-Directionally Graded Microstructures

    NASA Technical Reports Server (NTRS)

    Pindera, Marek-Jerzy; Aboudi, Jacob

    2000-01-01

    The objective of this two-year project was to develop and deliver to the NASA-Glenn Research Center a two-dimensional higher-order theory, and related computer codes, for the analysis and design of cylindrical functionally graded materials/structural components for use in advanced aircraft engines (e.g., combustor linings, rotor disks, heat shields, brisk blades). To satisfy this objective, two-dimensional version of the higher-order theory, HOTCFGM-2D, and four computer codes based on this theory, for the analysis and design of structural components functionally graded in the radial and circumferential directions were developed in the cylindrical coordinate system r-Theta-z. This version of the higher-order theory is a significant generalization of the one-dimensional theory, HOTCFGM-1D, developed during the FY97 for the analysis and design of cylindrical structural components with radially graded microstructures. The generalized theory is applicable to thin multi-phased composite shells/cylinders subjected to steady-state thermomechanical, transient thermal and inertial loading applied uniformly along the axial direction such that the overall deformation is characterized by a constant average axial strain. The reinforcement phases are uniformly distributed in the axial direction, and arbitrarily distributed in the radial and circumferential direction, thereby allowing functional grading of the internal reinforcement in the r-Theta plane. The four computer codes fgmc3dq.cylindrical.f, fgmp3dq.cylindrical.f, fgmgvips3dq.cylindrical.f, and fgmc3dq.cylindrical.transient.f are research-oriented codes for investigating the effect of functionally graded architectures, as well as the properties of the multi-phase reinforcement, in thin shells subjected to thermomechanical and inertial loading, on the internal temperature, stress and (inelastic) strain fields. The reinforcement distribution in the radial and circumferential directions is specified by the user. The thermal

  20. Light-Directed Ranging System Implementing Single Camera System for Telerobotics Applications

    NASA Technical Reports Server (NTRS)

    Wells, Dennis L. (Inventor); Li, Larry C. (Inventor); Cox, Brian J. (Inventor)

    1997-01-01

    A laser-directed ranging system has utility for use in various fields, such as telerobotics applications and other applications involving physically handicapped individuals. The ranging system includes a single video camera and a directional light source such as a laser mounted on a camera platform, and a remotely positioned operator. In one embodiment, the position of the camera platform is controlled by three servo motors to orient the roll axis, pitch axis and yaw axis of the video cameras, based upon an operator input such as head motion. The laser is offset vertically and horizontally from the camera, and the laser/camera platform is directed by the user to point the laser and the camera toward a target device. The image produced by the video camera is processed to eliminate all background images except for the spot created by the laser. This processing is performed by creating a digital image of the target prior to illumination by the laser, and then eliminating common pixels from the subsequent digital image which includes the laser spot. A reference point is defined at a point in the video frame, which may be located outside of the image area of the camera. The disparity between the digital image of the laser spot and the reference point is calculated for use in a ranging analysis to determine range to the target.

  1. Towards the bi-directional cellular automaton model with perception ranges

    NASA Astrophysics Data System (ADS)

    Zheng, Liang; Zhong, Shiquan; Ma, Shoufeng

    2013-07-01

    The traditional cellular automaton (CA) model assumes that drivers only receive information from the preceding vehicles, e.g. the brake light information. However, in reality, drivers not only perceive information from downstream but can also get upstream information, e.g. the honk stimulation. The CA model involving traffic information from downstream and upstream is called the bi-directional CA model here. Meanwhile, with the introduction of Connected Vehicle Technologies, the perception range of drivers is expected to significantly increase which can lead to more informed driving behavior. Such an impact cannot be easily modeled by traditional one-directional CA models. In this study, the perception ranges of both the brake light effect and honk stimulation are introduced into the bi-directional CA model. Fundamental diagrams and spatial-temporal diagrams are then analyzed and two methods, i.e. the traffic flow interruption effect and microscopic analysis of time series data, are utilized to distinguish the synchronized traffic flow. Further numerical results illustrate that the perception range and slow-to-start sensitivity threshold are two important factors to reproduce the synchronized flow, and consideration of the honk information and the larger perception range both benefit the stability of traffic flow, which implies the potential significance of the application of Connected Vehicle Technologies.

  2. From lignin to cycloparaffins and aromatics: directional synthesis of jet and diesel fuel range biofuels using biomass.

    PubMed

    Bi, Peiyan; Wang, Jicong; Zhang, Yajing; Jiang, Peiwen; Wu, Xiaoping; Liu, Junxu; Xue, He; Wang, Tiejun; Li, Quanxin

    2015-05-01

    The continual growth in commercial aviation fuels and more strict environmental legislations have led to immense interest in developing green aviation fuels from biomass. This paper demonstrated a controllable transformation of lignin into jet and diesel fuel range hydrocarbons, involving directional production of C8-C15 aromatics by the catalytic depolymerization of lignin into C6-C8 low carbon aromatic monomers coupled with the alkylation of aromatics, and the directional production of C8-C15 cycloparaffins by the hydrogenation of aromatics. The key step, the production of the desired C8-C15 aromatics with the selectivity up to 94.3%, was achieved by the low temperature alkylation reactions of the lignin-derived monomers using ionic liquid. The synthetic biofuels basically met the main technical requirements of conventional jet fuels. The transformation potentially provides a useful way for the development of cycloparaffinic and aromatic components in jet fuels using renewable lignocellulose biomass. PMID:25710678

  3. Long-range plasmonic directional coupler switches controlled by nematic liquid crystals.

    PubMed

    Zografopoulos, D C; Beccherelli, R

    2013-04-01

    A liquid-crystal tunable plasmonic optical switch based on a long-range metal stripe directional coupler is proposed and theoretically investigated. Extensive electro-optic tuning of the coupler's characteristics is demonstrated by introducing a nematic liquid crystal layer above two coplanar plasmonic waveguides. The switching properties of the proposed plasmonic structure are investigated through rigorous liquid-crystal studies coupled with a finite-element based analysis of light propagation. A directional coupler optical switch is demonstrated, which combines very low power consumption, low operation voltages, adjustable crosstalk and coupling lengths, along with sufficiently reduced insertion losses. PMID:23571914

  4. 75 FR 64309 - Components for Evaluation of Direct-Reading Monitors for Gases and Vapors and Addendum

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-19

    ... HUMAN SERVICES Centers for Disease Control and Prevention Components for Evaluation of Direct-Reading... addendum are entitled, respectively, ``Components for Evaluation of Direct-Reading Monitors for Gases and Vapors'' and ``Addendum to Components for Evaluation of Direct-Reading Monitors for Gases and...

  5. Direct detection of the Yarkovsky effect by radar ranging to ateroid 6489 Golevka

    NASA Technical Reports Server (NTRS)

    Chesley, S. R.; Ostro, S. J.; Vokrouhlicky, D.; Capek, D.; Giorgini, J. D.; Nolan, M. C.; Margot, J. L.; Hine, A. A.; Benner, L. A. M.; Chamberlin, A. B.

    2003-01-01

    Radar ranging from Arecibo, Puerto Rico, to the 0.5-kilometer near-Earth asteroid 6489 Golevka unambiguously reveals a small nongravitational acceleration caused by the anisotropic thermal emission of absorbed sunlight. The magnitude of this perturbation, known as the Yarkovsky effect, is a function of the asteroid's mass and surface thermal characteristics. Direct detection of the Yarkovsky effect on asteroids will help constrain their physical properties, such as bulk density, and refine their orbital paths.

  6. Resolving multiple propagation paths in time of flight range cameras using direct and global separation methods

    NASA Astrophysics Data System (ADS)

    Whyte, Refael; Streeter, Lee; Cree, Michael J.; Dorrington, Adrian A.

    2015-11-01

    Time of flight (ToF) range cameras illuminate the scene with an amplitude-modulated continuous wave light source and measure the returning modulation envelopes: phase and amplitude. The phase change of the modulation envelope encodes the distance travelled. This technology suffers from measurement errors caused by multiple propagation paths from the light source to the receiving pixel. The multiple paths can be represented as the summation of a direct return, which is the return from the shortest path length, and a global return, which includes all other returns. We develop the use of a sinusoidal pattern from which a closed form solution for the direct and global returns can be computed in nine frames with the constraint that the global return is a spatially lower frequency than the illuminated pattern. In a demonstration on a scene constructed to have strong multipath interference, we find the direct return is not significantly different from the ground truth in 33/136 pixels tested; where for the full-field measurement, it is significantly different for every pixel tested. The variance in the estimated direct phase and amplitude increases by a factor of eight compared with the standard time of flight range camera technique.

  7. Directly Reconstructing Principal Components of Heterogeneous Particles from Cryo-EM Images

    PubMed Central

    Tagare, Hemant D.; Kucukelbir, Alp; Sigworth, Fred J.; Wang, Hongwei; Rao, Murali

    2015-01-01

    Structural heterogeneity of particles can be investigated by their three-dimensional principal components. This paper addresses the question of whether, and with what algorithm, the three-dimensional principal components can be directly recovered from cryo-EM images. The first part of the paper extends the Fourier slice theorem to covariance functions showing that the three-dimensional covariance, and hence the principal components, of a heterogeneous particle can indeed be recovered from two-dimensional cryo-EM images. The second part of the paper proposes a practical algorithm for reconstructing the principal components directly from cryo-EM images without the intermediate step of calculating covariances. This algorithm is based on maximizing the (posterior) likelihood using the Expectation-Maximization algorithm. The last part of the paper applies this algorithm to simulated data and to two real cryo-EM data sets: a data set of the 70S ribosome with and without Elongation Factor-G (EF-G), and a data set of the inluenza virus RNA dependent RNA Polymerase (RdRP). The first principal component of the 70S ribosome data set reveals the expected conformational changes of the ribosome as the EF-G binds and unbinds. The first principal component of the RdRP data set reveals a conformational change in the two dimers of the RdRP. PMID:26049077

  8. Direct Chemical Vapor Deposition-Derived Graphene Glasses Targeting Wide Ranged Applications.

    PubMed

    Sun, Jingyu; Chen, Yubin; Priydarshi, Manish Kr; Chen, Zhang; Bachmatiuk, Alicja; Zou, Zhiyu; Chen, Zhaolong; Song, Xiuju; Gao, Yanfeng; Rümmeli, Mark H; Zhang, Yanfeng; Liu, Zhongfan

    2015-09-01

    Direct growth of graphene on traditional glasses is of great importance for various daily life applications. We report herein the catalyst-free atmospheric-pressure chemical vapor deposition approach to directly synthesizing large-area, uniform graphene films on solid glasses. The optical transparency and sheet resistance of such kinds of graphene glasses can be readily adjusted together with the experimentally tunable layer thickness of graphene. More significantly, these graphene glasses find a broad range of real applications by enabling the low-cost construction of heating devices, transparent electrodes, photocatalytic plates, and smart windows. With a practical scalability, the present work will stimulate various applications of transparent, electrically and thermally conductive graphene glasses in real-life scenarios. PMID:26305883

  9. Laser-Directed Ranging System Implementing Single Camera System for Telerobotics Applications

    NASA Technical Reports Server (NTRS)

    Wells, Dennis L. (Inventor); Li, Larry C. (Inventor); Cox, Brian J. (Inventor)

    1995-01-01

    The invention relates generally to systems for determining the range of an object from a reference point and, in one embodiment, to laser-directed ranging systems useful in telerobotics applications. Digital processing techniques are employed which minimize the complexity and cost of the hardware and software for processing range calculations, thereby enhancing the commercial attractiveness of the system for use in relatively low-cost robotic systems. The system includes a video camera for generating images of the target, image digitizing circuitry, and an associated frame grabber circuit. The circuit first captures one of the pairs of stereo video images of the target, and then captures a second video image of the target as it is partly illuminated by the light beam, suitably generated by a laser. The two video images, taken sufficiently close together in time to minimize camera and scene motion, are converted to digital images and then compared. Common pixels are eliminated, leaving only a digital image of the laser-illuminated spot on the target. Mw centroid of the laser illuminated spot is dm obtained and compared with a predetermined reference point, predetermined by design or calibration, which represents the coordinate at the focal plane of the laser illumination at infinite range. Preferably, the laser and camera are mounted on a servo-driven platform which can be oriented to direct the camera and the laser toward the target. In one embodiment the platform is positioned in response to movement of the operator's head. Position and orientation sensors are used to monitor head movement. The disparity between the digital image of the laser spot and the reference point is calculated for determining range to the target. Commercial applications for the system relate to active range-determination systems, such as those used with robotic systems in which it is necessary to determine the, range to a workpiece or object to be grasped or acted upon by a robot arm end

  10. Calorimetric support of directional-hemispherical reflection measurements in the infrared spectral range.

    PubMed

    Richter, W; Sarge, S M; Kämmer, F

    1994-03-01

    Measurements of the directional-hemispherical reflectance ρ with the Physikalisch-Technische Bundesanstalt IR sphere reflectometer have been confirmed by calorimetric determination of the absorptance α in the same geometrical conditions (irradiation at 10°, hemispherical reflection). The good agreement of ρ with (1 - α) on both highly reflecting and low-reflecting surfaces indicates that in the mid-IR spectral range the integrating sphere reflectometer is capable of essentially correct reflectance measurements of diffusely reflecting surfaces, with an estimated uncertainty of 0.01 after correction for a small systematic deviation. This capability opens up the possibility of developing IR reflectance standards. PMID:20862150

  11. A comparative study of optimum and suboptimum direct-detection laser ranging receivers

    NASA Technical Reports Server (NTRS)

    Abshire, J. B.

    1978-01-01

    A summary of previously proposed receiver strategies for direct-detection laser ranging receivers is presented. Computer simulations are used to compare performance of candidate implementation strategies in the 1- to 100-photoelectron region. Under the condition of no background radiation, the maximum-likelihood and minimum mean-square error estimators were found to give the same performance for both bell-shaped and rectangular optical-pulse shapes. For signal energies greater than 100 photoelectrons, the root-mean-square range error is shown to decrease as Q to the -1/2 power for bell-shaped pulses and Q to the -1 power for rectangular pulses, where Q represents the average pulse energy. Of several receiver implementations presented, the matched-filter peak detector was found to be preferable. A similar configuration, using a constant-fraction discriminator, exhibited a signal-level dependent time bias.

  12. Development of a Piezoelectric Vacuum Sensing Component for a Wide Pressure Range

    PubMed Central

    Wang, Bing-Yu; Hsieh, Fan-Chun; Lin, Che-Yu; Chen, Shao-En; Chen, Fong-Zhi; Wu, Chia-Che

    2014-01-01

    In this study, we develop a clamped–clamped beam-type piezoelectric vacuum pressure sensing element. The clamped–clamped piezoelectric beam is composed of a PZT layer and a copper substrate. A pair of electrodes is set near each end. An input voltage is applied to a pair of electrodes to vibrate the piezoelectric beam, and the output voltage is measured at the other pair. Because the viscous forces on the piezoelectric beam vary at different air pressures, the vibration of the beam depends on the vacuum pressure. The developed pressure sensor can sense a wide range of pressure, from 6.5 × 10−6 to 760 Torr. The experimental results showed that the output voltage is inversely proportional to the gas damping ratio, and thus, the vacuum pressure was estimated from the output voltage. PMID:25421736

  13. Short and medium range order in two-component silica glasses by positron annihilation spectroscopy

    SciTech Connect

    Inoue, K.; Kataoka, H.; Nagai, Y.; Hasegawa, M.; Kobayashi, Y.

    2014-05-28

    The dependence of chemical composition on the average sizes of subnanometer-scale intrinsic structural open spaces surrounded by glass random networks in two-component silica-based glasses was investigated systematically using positronium (Ps) confined in the open spaces. The average sizes of the open spaces for SiO{sub 2}-B{sub 2}O{sub 3} and SiO{sub 2}-GeO{sub 2} glasses are only slightly dependent on the chemical compositions because the B{sub 2}O{sub 3} and GeO{sub 2} are glass network formers that are incorporated into the glass network of the base SiO{sub 2}. However, the open space sizes for all SiO{sub 2}-R{sub 2}O (R = Li, Na, K) glasses, where R{sub 2}O is a glass network modifier that occupies the open spaces, decrease rapidly with an increase in the R{sub 2}O concentration. Despite the large difference in the ionic radii of the alkali metal (R) atoms, the open space sizes decrease similarly for all the alkali metal atoms studied. This dependence of the chemical composition on the open space sizes in SiO{sub 2}-R{sub 2}O observed by Ps shows that the alkali metal atoms do not randomly occupy the structural open spaces, but filling of the open spaces by R{sub 2}O proceeds selectively from the larger to the smaller open spaces as the R{sub 2}O concentrations are increased.

  14. Properties of pattern and component direction-selective cells in area MT of the macaque.

    PubMed

    Wang, Helena X; Movshon, J Anthony

    2016-06-01

    Neurons in area MT/V5 of the macaque visual cortex encode visual motion. Some cells are selective for the motion of oriented features (component direction-selective, CDS); others respond to the true direction of complex patterns (pattern-direction selective, PDS). There is a continuum of selectivity in MT, with CDS cells at one extreme and PDS cells at the other; we compute a pattern index that captures this variation. It is unknown how a neuron's pattern index is related to its other tuning characteristics. We therefore analyzed the responses of 792 MT cells recorded in the course of other experiments from opiate-anesthetized macaque monkeys, as a function of the direction, spatial frequency, drift rate, size, and contrast of sinusoidal gratings and of the direction and speed of random-dot textures. We also compared MT responses to those of 718 V1 cells. As expected, MT cells with higher pattern index tended to have stronger direction selectivity and broader direction tuning to gratings, and they responded better to plaids than to gratings. Strongly PDS cells also tended to have smaller receptive fields and stronger surround suppression. Interestingly, they also responded preferentially to higher drift rates and higher speeds of moving dots. The spatial frequency preferences of PDS cells depended strongly on their preferred temporal frequencies, whereas these preferences were independent in component-selective cells. Pattern direction selectivity is statistically associated with many response properties of MT cells but not strongly associated with any particular property. Pattern-selective signals are thus available in association with most other signals exported by MT. PMID:26561603

  15. Discussion on resolution and dynamic range of Se-TFT direct digital radiographic detector

    NASA Astrophysics Data System (ADS)

    Lee, Denny L. Y.; Cheung, Lawrence K.; Palecki, Eugene F.; Jeromin, Lothar S.

    1996-04-01

    The imaging performance of a new direct digital radiographic detector based on amorphous selenium and amorphous silicon TFT array which is under development is discussed. Progress has been made on the development of a multilayer digital x-ray detector panel with a structure consisting of a thin-film transistor pixel array, selenium x-ray photoconductor, dielectric layer and top electrode. An electronic system allows the rapid readout of image data which produces high resolution and wide dynamic range images. Using a straight edge, small wires and low contrast small holes targets, we have studied the spatial resolution, contrast detectability, and dynamic range of this new detector. Digital signals obtained from each pixel of this detector are almost linear with the total x-ray energy absorbed within the pixel area over a wide range of x-ray exposures. The resultant wide dynamic range allows extended latitude of exposure conditions and the enhancement or emphasis of different gray level regions from a single set of image data. For example, from one single exposure of the head, the soft tissue of the nose, detail structure of the teeth, as well as the bone structure of the neck can be examined by displaying and emphasizing selective gray levels of the image data. Image information obtained from this detector appears to be more evenly distributed over a wide dynamic range which is different from digital data obtained from other digital modalities such as the electrometer sensing of discharged potentials on photoconductors or from film digitization. Examples of images are shown. The discrete pixel structure of this detector and the higher intrinsic spatial resolution of selenium combine to produce image sharpness greater than those produced from digital detectors of similar pixel pitch using indirect conversion method or from digitizing film-screen images. The applicability of mathematical tools, such as the MTF which was developed primarily for analog images on a

  16. Analytic model for the direct and diffuse components of downwelling spectral irradiance in water.

    PubMed

    Gege, Peter

    2012-03-20

    The direct and diffuse components of downwelling irradiance have in general different path lengths in water, and hence they decrease differently with sensor depth. Furthermore, the ever-changing geometry of a wind-roughened and wave-modulated water surface induces uncorrelated intensity changes to these components. To cope with both effects, an analytic model of the downwelling irradiance in water was developed that calculates the direct and diffuse components separately. By assigning weights f(dd) and f(ds) to the intensities of the two components, measurements performed at arbitrary surface conditions can be analyzed by treating f(dd) and f(ds) as fit parameters. The model was validated against HydroLight and implemented into the public-domain software WASI. It was applied to data from three German lakes to determine the statistics of f(dd) and ff(ds), to derive the sensor depth of each measurement and to estimate the concentrations of water constituents. PMID:22441489

  17. SINGLE- AND TWO-COMPONENT GAMMA-RAY BURST SPECTRA IN THE FERMI GBM-LAT ENERGY RANGE

    SciTech Connect

    Veres, P.; Meszaros, P. E-mail: nnp@astro.psu.edu

    2012-08-10

    Most Fermi gamma-ray burst spectra appear as either a broken power law extending to GeV energies or as a broken power with a separate GeV power-law component. Here we show that such spectra can be understood in terms of magnetically dominated relativistic jets where a dissipative photosphere produces the prompt MeV emission, which is extended into the GeV range by inverse Compton scattering in the external shock, with possible contributions from a reverse shock as well. The bulk Lorentz factors required in these models are in the range of 300-600, and the MeV-GeV time delays arise naturally. In some cases an optical flash and a sub-dominant thermal component are also present.

  18. Modelling temporal variance of component temperatures and directional anisotropy over vegetated canopy

    NASA Astrophysics Data System (ADS)

    Bian, Zunjian; du, yongming; li, hua

    2016-04-01

    Land surface temperature (LST) as a key variable plays an important role on hydrological, meteorology and climatological study. Thermal infrared directional anisotropy is one of essential factors to LST retrieval and application on longwave radiance estimation. Many approaches have been proposed to estimate directional brightness temperatures (DBT) over natural and urban surfaces. While less efforts focus on 3-D scene and the surface component temperatures used in DBT models are quiet difficult to acquire. Therefor a combined 3-D model of TRGM (Thermal-region Radiosity-Graphics combined Model) and energy balance method is proposed in the paper for the attempt of synchronously simulation of component temperatures and DBT in the row planted canopy. The surface thermodynamic equilibrium can be final determined by the iteration strategy of TRGM and energy balance method. The combined model was validated by the top-of-canopy DBTs using airborne observations. The results indicated that the proposed model performs well on the simulation of directional anisotropy, especially the hotspot effect. Though we find that the model overestimate the DBT with Bias of 1.2K, it can be an option as a data reference to study temporal variance of component temperatures and DBTs when field measurement is inaccessible

  19. Single-step direct laser fabrication of complex shaped microoptical components

    NASA Astrophysics Data System (ADS)

    Žukauskas, Albertas; Tikuišis, Kristupas K.; Ščiuka, Mindaugas; Melninkaitis, Andrius; Gadonas, Roaldas; Reinhardt, Carsten; Malinauskas, Mangirdas

    2012-06-01

    We report on the fabrication of the minimized conventional microoptical components out of the hybrid organic- inorganic SZ2080 and SG4060 photoresins using laser direct writing technique. An ascending laser focus multiscan approach is introduced as a method for the structuring of 2D nanolines. The diameters and heights of the nanolines are comparable to the ones written with the electron beam lithography. Using our proposed laser direct writing approach one can write 3D microstructures with the 2D nanofeatures in a single step procedure. As demonstration of this technology, microlenses with 1D, 2D and circular transmission gratings were fabricated. Additionally, for the rst time, ISO certied laser-induced damage testing was applied to determine the optical breakdown threshold of the SZ2080 photoresin used for the laser direct writing.

  20. NEET-AMM Final Technical Report on Laser Direct Manufacturing (LDM) for Nuclear Power Components

    SciTech Connect

    Anderson, Scott; Baca, Georgina; O'Connor, Michael

    2015-12-31

    Final technical report summarizes the program progress and technical accomplishments of the Laser Direct Manufacturing (LDM) for Nuclear Power Components project. A series of experiments varying build process parameters (scan speed and laser power) were conducted at the outset to establish the optimal build conditions for each of the alloys. Fabrication was completed in collaboration with Quad City Manufacturing Laboratory (QCML). The density of all sample specimens was measured and compared to literature values. Optimal build process conditions giving fabricated part densities close to literature values were chosen for making mechanical test coupons. Test coupons whose principal axis is on the x-y plane (perpendicular to build direction) and on the z plane (parallel to build direction) were built and tested as part of the experimental build matrix to understand the impact of the anisotropic nature of the process.. Investigations are described 316L SS, Inconel 600, 718 and 800 and oxide dispersion strengthed 316L SS (Yttria) alloys.

  1. Thioarsenides: A case for long-range Lewis acid-base-directed van der Waals interactions

    SciTech Connect

    Gibbs, Gerald V.; Wallace, Adam F.; Downs, R. T.; Ross, Nancy L.; Cox, David F.; Rosso, Kevin M.

    2011-04-01

    Electron density distributions, bond paths, Laplacian and local energy density properties have been calculated for a number of As4Sn (n = 3,4,5) thioarsenide molecular crystals. On the basis of the distributions, the intramolecular As-S and As-As interactions classify as shared bonded interactions and the intermolecular As-S, As-As and S-S interactions classify as closed-shell van der Waals bonded interactions. The bulk of the intermolecular As-S bond paths link regions of locally concentrated electron density (Lewis base regions) with aligned regions of locally depleted electron density (Lewis acid regions) on adjacent molecules. The paths are comparable with intermolecular paths reported for several other molecular crystals that link aligned Lewis base and acid regions in a key-lock fashion, interactions that classified as long range Lewis acid-base directed van der Waals interactions. As the bulk of the intermolecular As-S bond paths (~70%) link Lewis acid-base regions on adjacent molecules, it appears that molecules adopt an arrangement that maximizes the number of As-S Lewis acid-base intermolecular bonded interactions. The maximization of the number of Lewis acid-base interactions appears to be connected with the close-packed array adopted by molecules: distorted cubic close-packed arrays are adopted for alacránite, pararealgar, uzonite, realgar and β-AsS and the distorted hexagonal close-packed arrays adopted by α- and β-dimorphite. A growth mechanism is proposed for thioarsenide molecular crystals from aqueous species that maximizes the number of long range Lewis acid-base vdW As-S bonded interactions with the resulting directed bond paths structuralizing the molecules as a molecular crystal.

  2. Thioarsenides: a case for long-range Lewis acid-base-directed van der Waals interactions

    NASA Astrophysics Data System (ADS)

    Gibbs, G. V.; Wallace, A. F.; Downs, R. T.; Ross, N. L.; Cox, D. F.; Rosso, K. M.

    2011-04-01

    Electron density distributions, bond paths, Laplacian and local-energy density properties have been calculated for a number of As4S n ( n = 3, 4 and 5) thioarsenide molecular crystals. On the basis of the distributions, the intramolecular As-S and As-As interactions classify as shared bonded interactions, and the intermolecular As-S, As-As and S-S interactions classify as closed-shell van der Waals (vdW) bonded interactions. The bulk of the intermolecular As-S bond paths link regions of locally concentrated electron density (Lewis-base regions) with aligned regions of locally depleted electron density (Lewis-acid regions) on adjacent molecules. The paths are comparable with intermolecular paths reported for several other molecular crystals that link aligned Lewis base and acid regions in a key-lock fashion, interactions that classified as long-range Lewis acid-base-directed vdW interactions. As the bulk of the intermolecular As-S bond paths (~70%) link Lewis acid-base regions on adjacent molecules, it appears that molecules adopt an arrangement that maximizes the number of As-S Lewis acid-base intermolecular bonded interactions. The maximization of the number of Lewis acid-base interactions appears to be connected with the close-packed array adopted by molecules: distorted cubic close-packed arrays are adopted for alacránite, pararealgar, uzonite, realgar and β-AsS and the distorted hexagonal close-packed arrays adopted by α- and β-dimorphite. A growth mechanism is proposed for thioarsenide molecular crystals from aqueous species that maximizes the number of long-range Lewis acid-base vdW As-S bonded interactions with the resulting directed bond paths structuralizing the molecules as a molecular crystal.

  3. Direct Imaging of Long-Range Exciton Transport in Quantum Dot Superlattices by Ultrafast Microscopy.

    PubMed

    Yoon, Seog Joon; Guo, Zhi; Dos Santos Claro, Paula C; Shevchenko, Elena V; Huang, Libai

    2016-07-26

    Long-range charge and exciton transport in quantum dot (QD) solids is a crucial challenge in utilizing QDs for optoelectronic applications. Here, we present a direct visualization of exciton diffusion in highly ordered CdSe QDs superlattices by mapping exciton population using ultrafast transient absorption microscopy. A temporal resolution of ∼200 fs and a spatial precision of ∼50 nm of this technique provide a direct assessment of the upper limit for exciton transport in QD solids. An exciton diffusion length of ∼125 nm has been visualized in the 3 ns experimental time window and an exciton diffusion coefficient of (2.5 ± 0.2) × 10(-2) cm(2) s(-1) has been measured for superlattices constructed from 3.6 nm CdSe QDs with center-to-center distance of 6.7 nm. The measured exciton diffusion constant is in good agreement with Förster resonance energy transfer theory. We have found that exciton diffusion is greatly enhanced in the superlattices over the disordered films with an order of magnitude higher diffusion coefficient, pointing toward the role of disorder in limiting transport. This study provides important understandings on energy transport mechanisms in both the spatial and temporal domains in QD solids. PMID:27387010

  4. Direct Measurements of Brown Carbon Absorption in A Wide Range of Biomass Burning Plumes

    NASA Astrophysics Data System (ADS)

    Murphy, S. M.; Pokhrel, R. P.; Beamesderfer, E.; Lack, D.; Langridge, J.; Wagner, N. L.

    2014-12-01

    Biomass burning represents one of the largest global sources of absorbing aerosol. Despite the importance of biomass burning emissions on the Earth's radiative balance, there remains significant uncertainty about the optical properties of emitted particles. Of particular interest is the impact of lensing on black carbon absorption and the impact of brown carbon. This presentation describes results from the Fire Lab at Missoula Experiment-4 (FLAME-4), which occurred in October 2012. Multi-channel photoacoustic (PAS) and Cavity Ringdown (CRDS) spectrometers were used to measure absorption, extinction, and absorption enhancement of aerosol particles produced from a wide range of globally relevant biomass fuels. Measurements were made at 405, 532, and 660 nm with duplicate channels at 405 and 660 measuring denuded particles, allowing for direct observation of the enhancement of absorption by black carbon particles caused by clear and brown organic coatings. Fuels were chosen based on their contribution to global wildfire emissions and a wide range of fuels will be discussed including some of the first optical measurements of Indonesian peat. The SSA and absorption angstrom exponent (AAE) of different biomass fuels will be explored and the relative importance of black and brown carbon emitted from different biomass fuels will be assessed, demonstrating that for certain fuels absorption from brown carbon is as important, or even more important than absorption from black carbon.

  5. EON: a component-based approach to automation of protocol-directed therapy.

    PubMed Central

    Musen, M A; Tu, S W; Das, A K; Shahar, Y

    1996-01-01

    Provision of automated support for planning protocol-directed therapy requires a computer program to take as input clinical data stored in an electronic patient-record system and to generate as output recommendations for therapeutic interventions and laboratory testing that are defined by applicable protocols. This paper presents a synthesis of research carried out at Stanford University to model the therapy-planning task and to demonstrate a component-based architecture for building protocol-based decision-support systems. We have constructed general-purpose software components that (1) interpret abstract protocol specifications to construct appropriate patient-specific treatment plans; (2) infer from time-stamped patient data higher-level, interval-based, abstract concepts; (3) perform time-oriented queries on a time-oriented patient database; and (4) allow acquisition and maintenance of protocol knowledge in a manner that facilitates efficient processing both by humans and by computers. We have implemented these components in a computer system known as EON. Each of the components has been developed, evaluated, and reported independently. We have evaluated the integration of the components as a composite architecture by implementing T-HELPER, a computer-based patient-record system that uses EON to offer advice regarding the management of patients who are following clinical trial protocols for AIDS or HIV infection. A test of the reuse of the software components in a different clinical domain demonstrated rapid development of a prototype application to support protocol-based care of patients who have breast cancer. PMID:8930854

  6. Spatiotemporal analysis of GPS time series in vertical direction using independent component analysis

    NASA Astrophysics Data System (ADS)

    Liu, Bin; Dai, Wujiao; Peng, Wei; Meng, Xiaolin

    2015-11-01

    GPS has been widely used in the field of geodesy and geodynamics thanks to its technology development and the improvement of positioning accuracy. A time series observed by GPS in vertical direction usually contains tectonic signals, non-tectonic signals, residual atmospheric delay, measurement noise, etc. Analyzing these information is the basis of crustal deformation research. Furthermore, analyzing the GPS time series and extracting the non-tectonic information are helpful to study the effect of various geophysical events. Principal component analysis (PCA) is an effective tool for spatiotemporal filtering and GPS time series analysis. But as it is unable to extract statistically independent components, PCA is unfavorable for achieving the implicit information in time series. Independent component analysis (ICA) is a statistical method of blind source separation (BSS) and can separate original signals from mixed observations. In this paper, ICA is used as a spatiotemporal filtering method to analyze the spatial and temporal features of vertical GPS coordinate time series in the UK and Sichuan-Yunnan region in China. Meanwhile, the contributions from atmospheric and soil moisture mass loading are evaluated. The analysis of the relevance between the independent components and mass loading with their spatial distribution shows that the signals extracted by ICA have a strong correlation with the non-tectonic deformation, indicating that ICA has a better performance in spatiotemporal analysis.

  7. Lateral Spectrum Splitting Concentrator Photovoltaics: Direct Measurement of Component and Submodule Efficiency

    SciTech Connect

    Xiaoting, W.; Waite, N.; Murcia, P.; Emery, K.; Steiner, M.; Kiamilev, F.; Goossen, K.; Honsberg, C.; Barnett, A.

    2012-03-01

    To achieve high energy conversion efficiency, a solar module architecture called lateral spectrum splitting concentrator photovoltaics (LSSCPV) is being developed. LSSCPV can concentrate available sunlight and laterally split a single beam into bands with different spectra for absorption by different solar cells with band gaps matched to the split spectrum. Test assemblies of a sample LSSCPV architecture were constructed, each of which contains four p-n junctions and two optical pieces. Independent experiments or simulations had been implemented on the components but by using optimal assumptions. In order to examine the actual performances of all the components, which are dependent on each other and the light source, direct outdoor measurements were made. A set of self-consistent efficiency definitions was articulated and a test bed was developed to measure the parameters required by the efficiency calculation. By comparing the component efficiency items derived from the outdoor measurement and the expected values based on independent simulations, the potential opportunities for efficiency improvement are determined. In the outdoor measurement at the University of Delaware, the optical component demonstrated 89.1% efficiency. Additional assemblies were tested at the National Renewable Energy Laboratory. One assembly demonstrated 36.7% submodule efficiency, which compares favorably with the 32.6% previously reported verified submodule efficiency.

  8. Hybrid optical (freeform) components--functionalization of nonplanar optical surfaces by direct picosecond laser ablation.

    PubMed

    Kleindienst, Roman; Kampmann, Ronald; Stoebenau, Sebastian; Sinzinger, Stefan

    2011-07-01

    The performance of optical systems is typically improved by increasing the number of conventionally fabricated optical components (spheres, aspheres, and gratings). This approach is automatically connected to a system enlargement, as well as potentially higher assembly and maintenance costs. Hybrid optical freeform components can help to overcome this trade-off. They merge several optical functions within fewer but more complex optical surfaces, e.g., elements comprising shallow refractive/reflective and high-frequency diffractive structures. However, providing the flexibility and precision essential for their realization is one of the major challenges in the field of optical component fabrication. In this article we present tailored integrated machining techniques suitable for rapid prototyping as well as the fabrication of molding tools for low-cost mass replication of hybrid optical freeform components. To produce the different feature sizes with optical surface quality, we successively combine mechanical machining modes (ultraprecision micromilling and fly cutting) with precisely aligned direct picosecond laser ablation in an integrated fabrication approach. The fabrication accuracy and surface quality achieved by our integrated fabrication approach are demonstrated with profilometric measurements and experimental investigations of the optical performance. PMID:21743521

  9. Liquid Phase Exfoliation of Two-Dimensional Materials by Directly Probing and Matching Surface Tension Components.

    PubMed

    Shen, Jianfeng; He, Yongmin; Wu, Jingjie; Gao, Caitian; Keyshar, Kunttal; Zhang, Xiang; Yang, Yingchao; Ye, Mingxin; Vajtai, Robert; Lou, Jun; Ajayan, Pulickel M

    2015-08-12

    Exfoliation of two-dimensional (2D) materials into mono- or few layers is of significance for both fundamental studies and potential applications. In this report, for the first time surface tension components were directly probed and matched to predict solvents with effective liquid phase exfoliation (LPE) capability for 2D materials such as graphene, h-BN, WS2, MoS2, MoSe2, Bi2Se3, TaS2, and SnS2. Exfoliation efficiency is enhanced when the ratios of the surface tension components of the applied solvent is close to that of the 2D material in question. We enlarged the library of low-toxic and common solvents for LPE. Our study provides distinctive insight into LPE and has pioneered a rational strategy for LPE of 2D materials with high yield. PMID:26200657

  10. Direct solar radiation up to 30 km and stratification of attenuation components in the stratosphere.

    PubMed

    Kondratiev, K Y; Nicolsky, G A; Badinov, I Y; Andreev, S D

    1967-02-01

    The balloon apparatus and some of the results of the direct solar radiation investigations up to 30 km in the middle belt of the Soviet Union in 1961-1965 are briefly described. Measurements of total direct solar radiation showed that the aerosol extinction properties in the free atmosphere are rather considerable, not only up to 30 km but also at the higher levels. The layered character of the stratospheric optical structure is demonstrated. The dynamics of layers and the possible influence of volcanic activity is discussed. Spectral investigations in the 0.35-13 micro region demonstrated that the stratospheric humidity is small, approximating 10(-6)-10(-5) g/g. The measurements in the visible spectrum confirmed that stratospheric aerosol component is essential, the stratospheric optical density being about 10(-4)-10(-3) km(-1). Comparison of the results of spectral and integral investigations indicates that the aerosol ext nction is also dominant above 30 km. PMID:20057727

  11. Direct Machining of Low-Loss THz Waveguide Components With an RF Choke

    PubMed Central

    Lewis, Samantha M.; Nanni, Emilio A.; Temkin, Richard J.

    2015-01-01

    We present results for the successful fabrication of low-loss THz metallic waveguide components using direct machining with a CNC end mill. The approach uses a split-block machining process with the addition of an RF choke running parallel to the waveguide. The choke greatly reduces coupling to the parasitic mode of the parallel-plate waveguide produced by the split-block. This method has demonstrated loss as low as 0.2 dB/cm at 280 GHz for a copper WR-3 waveguide. It has also been used in the fabrication of 3 and 10 dB directional couplers in brass, demonstrating excellent agreement with design simulations from 240–260 GHz. The method may be adapted to structures with features on the order of 200 μm. PMID:25821412

  12. Directional short range order in L10 FeMnPt magnetic thin films

    NASA Astrophysics Data System (ADS)

    Sun, Cheng-Jun; Xu, Dongbin; Heald, Steve M.; Chen, Jingsheng; Chow, Gan-Moog

    2011-10-01

    A method for investigating the directional short range order (DSRO) of an element of interest in L10 FeMnPt thin films using polarization-dependent x-ray absorption near edge structure (XANES) spectroscopy is described. The XANES calculations for both L10 FePt and L10 MnPt phases indicate that the height of the low-energy shoulder of the polarization-dependent XANES is proportional to the degree of DSRO of the element of interest in the case of L10 FePt and MnPt systems. The experimentally observed DSROs of Fe and Mn in L10 FeMnPt magnetic thin films are consistent with a decrease of ordering parameter with increasing Mn doping. We demonstrate theoretically and experimentally that the heights of the low-energy shoulder in the FeK- and MnK-edge polarization-dependent XANES are proportional to the DSROs of Fe and Mn, respectively.

  13. Directed alignment of conjugated polymers for enhanced long-range photocurrent collection

    NASA Astrophysics Data System (ADS)

    Li, Anton; Bilby, David; Dong, Ban; Kim, Jinsang; Green, Peter

    2015-03-01

    To realize the full potential of conjugated polymers, possessing anisotropic structure and properties, it is often desirable to extend their organization to larger length scales. An epitaxy-directing solvent additive 1,3,5-trichlorobenzene was combined with an off-center spin-casting technique to produce poly(3-hexylthiophene) (P3HT) fibers with uniaxial in-plane alignment on the centimeter scale, which were incorporated into planar heterojunction solar cells with PCBM acceptor. Topography and photocurrent were mapped by photoconductive AFM; in devices with aligned P3HT, local photocurrent measured on fibers was over 4 times higher than in control devices with unaligned polymer. Even at large distances (>200 μm) between laser spot (carrier excitation) and conductive probe (charge extraction), significant long-range photocurrent was measured in the aligned devices, especially when the separation was oriented parallel to the fiber alignment. Complementary TFT measurements of neat P3HT fibers revealed that the anisotropy of in-plane carrier mobilities was greater than a factor of 3. Together, these findings highlight the importance of conjugated polymer alignment for improving carrier transport and ultimately the performance of solar cells and other devices.

  14. Laser alchemy: direct writing of multifunctional components in a glass chip with femtosecond laser pulses

    NASA Astrophysics Data System (ADS)

    Liao, Yang; Lin, Jintian; Cheng, Ya

    2013-12-01

    Recently, hybrid integration of multifunctional micro-components for creating complex, intelligent micro/nano systems has attracted significant attention. These micro-/nano-systems have important applications in a variety of areas, such as healthcare, environment, communication, national security, and so on. However, fabrication of micro/nano systems incorporated with different functions is still a challenging task, which generally requires fabrication of discrete microcomponents beforehand followed by assembly and packaging procedures. Furthermore, current micro-/nano-fabrication techniques are mainly based on the well-established planar lithographic approach, which suffer from severe issues in producing three dimensional (3D) structures with complex geometries and arbitrary configurations. In recent years, the rapid development of femtosecond laser machining technology has enabled 3D direct fabrication and integration of multifunctional components, such as microfluidics, microoptics, micromechanics, microelectronics, etc., into single substrates. In this invited talk, we present our recent progress in this active area. Particularly, we focus on fabrication of 3D micro- and nanofluidic devices and 3D high-Q microcavities in glass substrates by femtosecond laser direct writing.

  15. Direct interaction of mitochondrial targeting presequences with purified components of the TIM23 protein complex.

    PubMed

    Marom, Milit; Dayan, Dana; Demishtein-Zohary, Keren; Mokranjac, Dejana; Neupert, Walter; Azem, Abdussalam

    2011-12-23

    Precursor proteins that are imported from the cytosol into the matrix of mitochondria carry positively charged amphipathic presequences and cross the inner membrane with the help of vital components of the TIM23 complex. It is currently unclear which subunits of the TIM23 complex recognize and directly bind to presequences. Here we analyzed the binding of presequence peptides to purified components of the TIM23 complex. The interaction of three different presequences with purified soluble domains of yeast Tim50 (Tim50IMS), Tim23 (Tim23IMS), and full-length Tim44 was examined. Using chemical cross-linking and surface plasmon resonance we demonstrate, for the first time, the ability of purified Tim50IMS and Tim44 to interact directly with the yeast Hsp60 presequence. We also analyzed their interaction with presequences derived from precursors of yeast mitochondrial 70-kDa heat shock protein (mHsp70) and of bovine cytochrome P450SCC. Moreover, we characterized the nature of the interactions and determined their KDs. On the basis of our results, we suggest a mechanism of translocation where stronger interactions of the presequences on the trans side of the channel support the import of precursor proteins through TIM23 into the matrix. PMID:21969381

  16. Direct Interaction of Mitochondrial Targeting Presequences with Purified Components of the TIM23 Protein Complex*

    PubMed Central

    Marom, Milit; Dayan, Dana; Demishtein-Zohary, Keren; Mokranjac, Dejana; Neupert, Walter; Azem, Abdussalam

    2011-01-01

    Precursor proteins that are imported from the cytosol into the matrix of mitochondria carry positively charged amphipathic presequences and cross the inner membrane with the help of vital components of the TIM23 complex. It is currently unclear which subunits of the TIM23 complex recognize and directly bind to presequences. Here we analyzed the binding of presequence peptides to purified components of the TIM23 complex. The interaction of three different presequences with purified soluble domains of yeast Tim50 (Tim50IMS), Tim23 (Tim23IMS), and full-length Tim44 was examined. Using chemical cross-linking and surface plasmon resonance we demonstrate, for the first time, the ability of purified Tim50IMS and Tim44 to interact directly with the yeast Hsp60 presequence. We also analyzed their interaction with presequences derived from precursors of yeast mitochondrial 70-kDa heat shock protein (mHsp70) and of bovine cytochrome P450SCC. Moreover, we characterized the nature of the interactions and determined their KDs. On the basis of our results, we suggest a mechanism of translocation where stronger interactions of the presequences on the trans side of the channel support the import of precursor proteins through TIM23 into the matrix. PMID:21969381

  17. Directing folding pathways for multi-component DNA origami nanostructures with complex topology

    NASA Astrophysics Data System (ADS)

    Marras, A. E.; Zhou, L.; Kolliopoulos, V.; Su, H.-J.; Castro, C. E.

    2016-05-01

    Molecular self-assembly has become a well-established technique to design complex nanostructures and hierarchical mesoscale assemblies. The typical approach is to design binding complementarity into nucleotide or amino acid sequences to achieve the desired final geometry. However, with an increasing interest in dynamic nanodevices, the need to design structures with motion has necessitated the development of multi-component structures. While this has been achieved through hierarchical assembly of similar structural units, here we focus on the assembly of topologically complex structures, specifically with concentric components, where post-folding assembly is not feasible. We exploit the ability to direct folding pathways to program the sequence of assembly and present a novel approach of designing the strand topology of intermediate folding states to program the topology of the final structure, in this case a DNA origami slider structure that functions much like a piston-cylinder assembly in an engine. The ability to program the sequence and control orientation and topology of multi-component DNA origami nanostructures provides a foundation for a new class of structures with internal and external moving parts and complex scaffold topology. Furthermore, this work provides critical insight to guide the design of intermediate states along a DNA origami folding pathway and to further understand the details of DNA origami self-assembly to more broadly control folding states and landscapes.

  18. Specialized filopodia direct long-range transport of SHH during vertebrate tissue patterning.

    PubMed

    Sanders, Timothy A; Llagostera, Esther; Barna, Maria

    2013-05-30

    The ability of signalling proteins to traverse tissues containing tightly packed cells is of fundamental importance for cell specification and tissue development; however, how this is achieved at a cellular level remains poorly understood. For more than a century, the vertebrate limb bud has served as a model for studying cell signalling during embryonic development. Here we optimize single-cell real-time imaging to delineate the cellular mechanisms for how signalling proteins, such as sonic hedgehog (SHH), that possess membrane-bound covalent lipid modifications traverse long distances within the vertebrate limb bud in vivo. By directly imaging SHH ligand production under native regulatory control in chick (Gallus gallus) embryos, our findings show that SHH is unexpectedly produced in the form of a particle that remains associated with the cell via long cytoplasmic extensions that span several cell diameters. We show that these cellular extensions are a specialized class of actin-based filopodia with novel cytoskeletal features that have not been previously described. Notably, particles containing SHH travel along these extensions with a net anterograde movement within the field of SHH cell signalling. We further show that in SHH-responding cells, specific subsets of SHH co-receptors, including cell adhesion molecule downregulated by oncogenes (CDO) and brother of CDO (BOC), actively distribute and co-localize in specific micro-domains within filopodial extensions, far from the cell body. Stabilized interactions are formed between filopodia containing SHH ligand and those containing co-receptors over a long range. These results suggest that contact-mediated release propagated by specialized filopodia contributes to the delivery of SHH at a distance. Together, these studies identify an important mode of communication between cells that considerably extends our understanding of ligand movement and reception during vertebrate tissue patterning. PMID:23624372

  19. 30 CFR 75.703 - Grounding offtrack direct-current machines and the enclosures of related detached components.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Grounding offtrack direct-current machines and...-UNDERGROUND COAL MINES Grounding § 75.703 Grounding offtrack direct-current machines and the enclosures of related detached components. The frames of all offtrack direct-current machines and the enclosures...

  20. 30 CFR 75.703 - Grounding offtrack direct-current machines and the enclosures of related detached components.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Grounding offtrack direct-current machines and...-UNDERGROUND COAL MINES Grounding § 75.703 Grounding offtrack direct-current machines and the enclosures of related detached components. The frames of all offtrack direct-current machines and the enclosures...

  1. 30 CFR 75.703 - Grounding offtrack direct-current machines and the enclosures of related detached components.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Grounding offtrack direct-current machines and...-UNDERGROUND COAL MINES Grounding § 75.703 Grounding offtrack direct-current machines and the enclosures of related detached components. The frames of all offtrack direct-current machines and the enclosures...

  2. Selection of astrophysical/astronomical/solar sites at the Argentina East Andes range taking into account atmospheric components

    NASA Astrophysics Data System (ADS)

    Piacentini, R. D.; García, B.; Micheletti, M. I.; Salum, G.; Freire, M.; Maya, J.; Mancilla, A.; Crinó, E.; Mandat, D.; Pech, M.; Bulik, T.

    2016-06-01

    In the present work we analyze sites in the Argentinian high Andes mountains as possible places for astrophysical/astronomical/solar observatories. They are located at: San Antonio de los Cobres (SAC) and El Leoncito/CASLEO region: sites 1 and 2. We consider the following atmospheric components that affect, in different and specific wavelength ranges, the detection of photons of astronomical/astrophysical/solar origin: ozone, microscopic particles, precipitable water and clouds. We also determined the atmospheric radiative transmittance in a day near the summer solstice at noon, in order to confirm the clearness of the sky in the proposed sites at SAC and El Leoncito. Consequently, all the collected and analyzed data in the present work, indicate that the proposed sites are very promising to host astrophysical/astronomical/solar observatories. Some atmospheric components, like aerosols, play a significant role in the attenuation of light (Cherencov and/or fluorescence) detected in cosmic rays (particles or gamma photons) astrophysical observatories, while others, like ozone have to be considered in astronomical/solar light detection.

  3. Distinct Roles of Cytoskeletal Components in Immunological Synapse Formation and Directed Secretion

    PubMed Central

    Ueda, Hironori; Zhou, Jie; Xie, Jianming

    2015-01-01

    A hallmark of CD4+ T cell activation and immunological synapse (IS) formation is the migration of the microtubule organization center and associated organelles toward the APCs. In this study, we found that when murine CD4+ T cells were treated with a microtubule-destabilizing agent (vinblastine) after the formation of IS, the microtubule organization center dispersed and all of the major cellular organelles moved away from the IS. Cytokines were no longer directed toward the synapse but were randomly secreted in quantities similar to those seen in synaptic secretion. However, if the actin cytoskeleton was disrupted at the same time with cytochalasin D, the organelles did not shift away from the IS. These findings suggest that there is a complex interplay between the microtubules and actin cytoskeleton, where microtubules are important for directing particular cytokines into the synapse, but they are not involved in the amount of cytokines that are produced for at least 1 h after IS formation. In addition, we found that they play a critical role in mobilizing organelles to reorient toward the synapse during T cell activation and in stabilizing organelles against the force that is generated through actin polymerization so that they move toward the APCs. These findings show that there is a complex interplay between these major cytoskeletal components during synapse formation and maintenance. PMID:26392461

  4. Effect of Directional Array Size on the Measurement of Airframe Noise Components

    NASA Technical Reports Server (NTRS)

    Brooks, Thomas F.; Humphreys, William M., Jr.

    1999-01-01

    A study was conducted to examine the effects of overall size of directional (or phased) arrays on the measurement of aeroacoustic components. An airframe model was mounted in the potential core of an open-jet windtunnel, with the directional arrays located outside the flow in an anechoic environment. Two array systems were used; one with a solid measurement angle that encompasses 31.6 deg.of source directivity and a smaller one that encompasses 7.2 deg. The arrays, and sub-arrays of various sizes, measured noise from a calibrator source and flap edge model setups. In these cases, noise was emitted from relatively small, but finite size source regions, with intense levels compared to other sources. Although the larger arrays revealed much more source region detail, the measured source levels were substantially reduced due to finer resolution compared to that of the smaller arrays. To better understand the measurements quantitatively, an analytical model was used to define the basic relationships between array to source region sizes and measured output level. Also, the effect of noise scattering by shear layer turbulence was examined using the present data and those of previous studies. Taken together, the two effects were sufficient to explain spectral level differences between arrays of different sizes. An important result of this study is that total (integrated) noise source levels are retrievable and the levels are independent of the array size as long as certain experimental and processing criteria are met. The criteria for both open and closed tunnels are discussed. The success of special purpose diagonal-removal processing in obtaining integrated results is apparently dependent in part on source distribution. Also discussed is the fact that extended sources are subject to substantial measurement error, especially for large arrays.

  5. Contributions of biarticular myogenic components to the limitation of the range of motion after immobilization of rat knee joint

    PubMed Central

    2014-01-01

    Background Muscle atrophy caused by immobilization in the shortened position is characterized by a decrease in the size or cross-sectional area (CSA) of myofibers and decreased muscle length. Few studies have addressed the relationship between limitation of the range of motion (ROM) and the changes in CSA specifically in biarticular muscles after atrophy because of immobilization. We aimed to determine the contribution of 2 distinct muscle groups, the biarticular muscles of the post thigh (PT) and those of the post leg (PL), to the limitation of ROM as well as changes in the myofiber CSAs after joint immobilization surgery. Methods Male Wistar rats (n = 40) were randomly divided into experimental and control groups. In the experimental group, the left knee was surgically immobilized by external fixation for 1, 2, 4, 8, or 16 weeks (n = 5 each) and sham surgery was performed on the right knee. The rats in the control groups (n = 3 per time point) did not undergo surgery. After the indicated immobilization periods, myotomy of the PT or PL biarticular muscles was performed and the ROM was measured. The hamstrings and gastrocnemius muscles from the animals operated for 1 or 16 weeks were subjected to morphological analysis. Results In immobilized knees, the relative contribution of the PT biarticular myogenic components to the total restriction reached 80% throughout the first 4 weeks and decreased thereafter. The relative contribution of the PL biarticular myogenic components remained <20% throughout the immobilization period. The ratio of the myofiber CSA of the immobilized to that of the sham-operated knees was significantly lower at 16 weeks after surgery than at 1 week after surgery only in the hamstrings. Conclusions The relative contribution of the PT and PL components to myogenic contracture did not significantly change during the experimental period. However, the ratio of hamstrings CSAs to the sham side was larger than the ratio of medial

  6. Site-Directed Mutagenesis to Improve Sensitivity of a Synthetic Two-Component Signaling System.

    PubMed

    Olshefsky, Audrey; Shehata, Laila; Kuldell, Natalie

    2016-01-01

    Two-component signaling (2CS) systems enable bacterial cells to respond to changes in their local environment, often using a membrane-bound sensor protein and a cytoplasmic responder protein to regulate gene expression. Previous work has shown that Escherichia coli's natural EnvZ/OmpR 2CS could be modified to construct a light-sensing bacterial photography system. The resulting bacterial photographs, or "coliroids," rely on a phosphotransfer reaction between Cph8, a synthetic version of EnvZ that senses red light, and OmpR. Gene expression changes can be visualized through upregulation of a LacZ reporter gene by phosphorylated OmpR. Unfortunately, basal LacZ expression leads to a detectable reporter signal even when cells are grown in the light, diminishing the contrast of the coliroids. We performed site-directed mutagenesis near the phosphotransfer site of Cph8 to isolate mutants with potentially improved image contrast. Five mutants were examined, but only one of the mutants, T541S, increased the ratio of dark/light gene expression, as measured by β-galactosidase activity. The ratio changed from 2.57 fold in the starting strain to 5.59 in the T541S mutant. The ratio decreased in the four other mutant strains we examined. The phenotype observed in the T541S mutant strain may arise because the serine sidechain is chemically similar but physically smaller than the threonine sidechain. This may minimally change the protein's local structure, but may be less sterically constrained when compared to threonine, resulting in a higher probability of a phosphotransfer event. Our initial success pairing synthetic biology and site-directed mutagenesis to optimize the bacterial photography system's performance encourages us to imagine further improvements to the performance of this and other synthetic systems, especially those based on 2CS signaling. PMID:26799494

  7. Site-Directed Mutagenesis to Improve Sensitivity of a Synthetic Two-Component Signaling System

    PubMed Central

    Kuldell, Natalie

    2016-01-01

    Two-component signaling (2CS) systems enable bacterial cells to respond to changes in their local environment, often using a membrane-bound sensor protein and a cytoplasmic responder protein to regulate gene expression. Previous work has shown that Escherichia coli’s natural EnvZ/OmpR 2CS could be modified to construct a light-sensing bacterial photography system. The resulting bacterial photographs, or “coliroids,” rely on a phosphotransfer reaction between Cph8, a synthetic version of EnvZ that senses red light, and OmpR. Gene expression changes can be visualized through upregulation of a LacZ reporter gene by phosphorylated OmpR. Unfortunately, basal LacZ expression leads to a detectable reporter signal even when cells are grown in the light, diminishing the contrast of the coliroids. We performed site-directed mutagenesis near the phosphotransfer site of Cph8 to isolate mutants with potentially improved image contrast. Five mutants were examined, but only one of the mutants, T541S, increased the ratio of dark/light gene expression, as measured by β-galactosidase activity. The ratio changed from 2.57 fold in the starting strain to 5.59 in the T541S mutant. The ratio decreased in the four other mutant strains we examined. The phenotype observed in the T541S mutant strain may arise because the serine sidechain is chemically similar but physically smaller than the threonine sidechain. This may minimally change the protein’s local structure, but may be less sterically constrained when compared to threonine, resulting in a higher probability of a phosphotransfer event. Our initial success pairing synthetic biology and site-directed mutagenesis to optimize the bacterial photography system’s performance encourages us to imagine further improvements to the performance of this and other synthetic systems, especially those based on 2CS signaling. PMID:26799494

  8. 30 CFR 75.703 - Grounding offtrack direct-current machines and the enclosures of related detached components.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Grounding offtrack direct-current machines and the enclosures of related detached components. 75.703 Section 75.703 Mineral Resources MINE SAFETY AND...-UNDERGROUND COAL MINES Grounding § 75.703 Grounding offtrack direct-current machines and the enclosures...

  9. 30 CFR 75.703 - Grounding offtrack direct-current machines and the enclosures of related detached components.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Grounding offtrack direct-current machines and the enclosures of related detached components. 75.703 Section 75.703 Mineral Resources MINE SAFETY AND...-UNDERGROUND COAL MINES Grounding § 75.703 Grounding offtrack direct-current machines and the enclosures...

  10. Direct-View Multi-Point Two-Component Interferometric Rayleigh Scattering Velocimeter

    NASA Technical Reports Server (NTRS)

    Bivolaru, Daniel; Danehy, Paul M.; Gaffney, Richard L., Jr.; Cutler, Andrew D.

    2008-01-01

    This paper describes an instantaneous velocity measurement system based on the Doppler shift of elastically scattered laser light from gas molecules (Rayleigh scattering) relative to an incident laser. The system uses a pulsed laser as the light source, direct-viewing optics to collect the scattered light, an interferometer to analyze spectrally the scattered light mixed with the incident laser light, and a CCD camera to capture the resulting interferogram. The system is capable of simultaneous, spatially (approximately 0.2 mm(exp 3)) and temporally (approximately 40 ns) resolved, multiple point measurements of two orthogonal components of flow velocity in the presence of background scattered light, acoustic noise and vibrations, and flow particulates. Measurements in a large-scale axi-symmetric Mach 1.6 H2-air combustion-heated jet running at a flow sensible enthalpy specific to Mach 5.5 hypersonic flight are performed to demonstrate the technique. The measurements are compared with CFD calculations using a finite-volume discretization of the Favre-averaged Navier-Stokes equations (VULCAN code).

  11. Remote sensing of row crop structure and component temperatures using directional radiometric temperatures and inversion techniques

    NASA Technical Reports Server (NTRS)

    Kimes, D. S.

    1983-01-01

    A physically based sensor response model of a row crop was used as the mathematical framework from which several inversion strategies were tested for extracting row structure information and component temperatures using a series of sensor view angles. The technique was evaluated on ground-based radiometric thermal infrared data of a cotton row crop that covered 48 percent of the ground in the vertical projection. The results showed that the accuracies of the predicted row heights and widths, vegetation temperatures, and soil temperatures of the cotton row crop were on the order of 5 cm, 1 deg, and 2 deg C, respectively. The inversion techniques can be applied to directional sensor data from aircraft platforms and even space platforms if the effects of atmospheric absorption and emission can be corrected. In theory, such inversion techniques can be applied to a wide variety of vegetation types and thus can have significant implications for remote sensing research and applications in disciplines that deal with incomplete vegetation canopies.

  12. Non-mechanical scanning laser Doppler velocimetry with sensitivity to direction of transverse velocity component using optical serrodyne frequency shifting

    NASA Astrophysics Data System (ADS)

    Maru, Koichi; Watanabe, Kento

    2014-05-01

    This paper proposes a non-mechanical axial scanning laser Doppler velocimeter (LDV) with sensitivity to the direction of the transverse velocity component using optical serrodyne frequency shifting. Serrodyne modulation via the electro-optic effect of a LiNbO3 (LN) phase shifter is employed to discriminate the direction of the transverse velocity component. The measurement position is scanned without any moving mechanism in the probe by changing the wavelength of the light input to the probe. The experimental results using a sensor probe setup indicate that both the scan of the measurement position and the introduction of directional sensitivity are successfully demonstrated.

  13. Policy Directions for U. S. Agriculture; Long-Range Choices in Farming and Rural Living.

    ERIC Educational Resources Information Center

    Clawson, Marion

    A comprehensive view of agriculture is presented in this volume written to aid critical re-examination of long-range agricultural policy. Farm people, rural institutions and services, rural towns, the spatial organization of agriculture, and its capital structure, in addition to the usual subjects of agricultural output, demand, trade, price, and…

  14. Spur-free dynamic range measurements of a fiber optic link with traveling wave linearized directional coupler modulators

    NASA Astrophysics Data System (ADS)

    Schaffner, James H.; Lam, Juan F.; Gaeta, Celestino J.; Tangonan, Gregory L.; Joyce, Robert L.; Farwell, Mark L.; Chang, William S. C.

    1994-02-01

    Two-tone testing was performed on a laboratory fiber optic link with LiNbO3 traveling wave linearized directional coupler modulators. The third-order distortion was measured at 500 MHz and 1000 MHz, and the spur-free dynamic range was determined. Two modulator configurations, with either one or two passive bias sections, were tested and the results were compared with measurements of simple directional coupler modulators. A 9.5-11 dB improvement in the dynamic range was found in the links employing the linearized modulators.

  15. Direct observation and quantification of extracellular long-range electron flow in anaerobic bacteria

    NASA Astrophysics Data System (ADS)

    Malvankar, Nikhil; Yalcin, Sibel; Vargas, Madeline; Tuominen, Mark; Lovley, Derek

    2013-03-01

    Some anaerobic microorganisms are capable of transporting electrons outside their cell to distant electron acceptors such as metals, minerals or partner species. Previous studies have focused primarily on transport over short distances (< 1 μm) via diffusion of molecular intermediates, or alternatively via tunneling or thermally-activated hopping across biomolecules. However, we have found that Geobacter sulfurreducens can transport electrons over long distances (> 10 μm) using pili filaments that show organic metal-like conductivity. Pili also enable direct exchange of electrons among syntrophic Geobacter co-cultures. In order to establish the physical principles underlying this remarkable electron transport, we have employed a novel scanning probe microscopy-based method to perform quantitative measurements of electron flow at a single cell level under physiological conditions. Using this nanoscopic approach, we have directly observed the propagation and distribution of injected electrons in individual native bacterial extracellular proteins. Our direct measurements demonstrate unambiguously for the first time that the pili of G. sulfurreducens are a novel class of electronically functional proteins that can sustain electron flow in a surprising manner that has not been observed previously in any other natural protein. Funded by Office of Naval Research, DOE Genomic Sciences and NSF-NSEC Center for Hierarchical Manufacturing grant no. CMMI-1025020.

  16. Using individual differences to predict job performance: correcting for direct and indirect restriction of range.

    PubMed

    Sjöberg, Sofia; Sjöberg, Anders; Näswall, Katharina; Sverke, Magnus

    2012-08-01

    The present study investigates the relationship between individual differences, indicated by personality (FFM) and general mental ability (GMA), and job performance applying two different methods of correction for range restriction. The results, derived by analyzing meta-analytic correlations, show that the more accurate method of correcting for indirect range restriction increased the operational validity of individual differences in predicting job performance and that this increase primarily was due to general mental ability being a stronger predictor than any of the personality traits. The estimates for single traits can be applied in practice to maximize prediction of job performance. Further, differences in the relative importance of general mental ability in relation to overall personality assessment methods was substantive and the estimates provided enables practitioners to perform a correct utility analysis of their overall selection procedure. PMID:22612634

  17. Direct writing of fiber optic components in photonic crystal fibers and other specialty fibers

    NASA Astrophysics Data System (ADS)

    Fernandes, Luis Andre; Sezerman, Omur; Best, Garland; Ng, Mi Li; Kane, Saidou

    2016-04-01

    Femtosecond direct laser writing has recently shown great potential for the fabrication of complex integrated devices in the cladding of optical fibers. Such devices have the advantage of requiring no bulk optical components and no breaks in the fiber path, thus reducing the need for complicated alignment, eliminating contamination, and increasing stability. This technology has already found applications using combinations of Bragg gratings, interferometers, and couplers for the fabrication of optical filters, sensors, and power monitors. The femtosecond laser writing method produces a local modification of refractive index through non-linear absorption of the ultrafast laser pulses inside the dielectric material of both the core and cladding of the fiber. However, fiber geometries that incorporate air or hollow structures, such as photonic crystal fibers (PCFs), still present a challenge since the index modification regions created by the writing process cannot be generated in the hollow regions of the fiber. In this work, the femtosecond laser method is used together with a pre-modification method that consists of partially collapsing the hollow holes using an electrical arc discharge. The partial collapse of the photonic band gap structure provides a path for femtosecond laser written waveguides to couple light from the core to the edge of the fiber for in-line power monitoring. This novel approach is expected to have applications in other specialty fibers such as suspended core fibers and can open the way for the integration of complex devices and facilitate miniaturization of optical circuits to take advantage of the particular characteristics of the PCFs.

  18. Direct Numerical Simulation and Theories of Wall Turbulence with a Range of Pressure Gradients

    NASA Technical Reports Server (NTRS)

    Coleman, G. N.; Garbaruk, A.; Spalart, P. R.

    2014-01-01

    A new Direct Numerical Simulation (DNS) of Couette-Poiseuille flow at a higher Reynolds number is presented and compared with DNS of other wall-bounded flows. It is analyzed in terms of testing semi-theoretical proposals for universal behavior of the velocity, mixing length, or eddy viscosity in pressure gradients, and in terms of assessing the accuracy of two turbulence models. These models are used in two modes, the traditional one with only a dependence on the wall-normal coordinate y, and a newer one in which a lateral dependence on z is added. For pure Couette flow and the Couette-Poiseuille case considered here, this z-dependence allows some models to generate steady streamwise vortices, which generally improves the agreement with DNS and experiment. On the other hand, it complicates the comparison between DNS and models.

  19. Bi-directional fast flow sensor with a large dynamic range

    NASA Astrophysics Data System (ADS)

    de Bree, Hans-Elias; Jansen, Henri V.; Lammerink, Theo S. J.; Krijnen, Gijs J. M.; Elwenspoek, Miko

    1999-06-01

    In this article an extended mass-flow sensor is presented. Apart from the magnitude of the flow, as an add-on to the traditional anemometer, this sensor also measures the direction of the flow. This is of interest for the flow sensor market in general, and more in particular for the safety monitoring of low over-pressure systems like surgeries and cleanrooms where the risk of reverse flow needs to be avoided at all times. It detects the smallest amount of gas-flow, down to approximately 100 µm s-1 airflow up to high flow levels of 1 m s-1. The response time is of the order of milliseconds.

  20. Nanometer-range atomic order directly recovered from resonant diffuse scattering

    NASA Astrophysics Data System (ADS)

    Kopecký, M.; Kub, J.; Fábry, J.; Hlinka, J.

    2016-02-01

    The method for three-dimensional imaging with an atomic resolution, based on the measurement of resonant scattering of x rays, is presented and tested on a nanoscale-range occupational ordering of niobium and magnesium ions in the lead magnesium niobate (PbMg1 /3Nb2 /3O3 ) single crystal. X-ray diffuse scattering experiments performed at two wavelengths close to the absorption edge of niobium allowed us to record two 1024 ×1024 ×1024 data sets of scattering intensities covering densely a large volume of the reciprocal space (up to Qmax=8.5 Å-1 , with steps smaller than δ Q =0.05 Å-1 ). It is demonstrated that the anomalous part of the scattering intensity, including both discrete diffraction spots and diffuse scattering, can be employed to reconstruct the local atomic environment around the niobium cation up to the distance of several nanometers.

  1. Principal component analysis of palaeomagnetic directions: converting a Maximum Angular Deviation (MAD) into an α95 angle

    NASA Astrophysics Data System (ADS)

    Khokhlov, A.; Hulot, G.

    2016-01-01

    Directions recovered from palaeomagnetic samples are usually archived with some quantitative information about their precision, most often in the form of a so-called α95 angle. Such angles are classically co-estimated with the recovered palaeomagnetic direction from a collection of samples providing individual estimates of this direction. In some instances, however, palaeomagnetic directions have to be inferred from a single sample in which case no α95 angle can be recovered in this way. Fortunately, the progressive demagnetization techniques and principal component analysis universally used to recover directional information from single samples provide alternative measures of the error affecting the recovered direction, known as Maximum Angular Deviation (MAD) angles. These have so far only been considered as rough quality indicators. Here, however, we show that directions recovered in this way can be assumed to satisfy a Fisher distribution, and that the corresponding MAD angles can be rescaled into α95 estimates by multiplying it by an appropriate factor, which only depends on the number of demagnetization steps used in the principal component analysis and on whether one relies on a standard or a so-called `anchored' principal component analysis. These coefficients have been tabulated and practical recommendations for taking advantage of them outlined in the final section of the text. They provide simple means for users to produce much needed error bars on declination and inclination time series recovered from sedimentary long sequences.

  2. Data-Based Locally Directed Evaluation of Vocational Education Programs. Component 6. Evaluation of Occupational Competencies.

    ERIC Educational Resources Information Center

    Florida State Univ., Tallahassee. Program of Vocational Education.

    Part of a system by which local education agency (LEA) personnel may evaluate secondary and postsecondary vocational education programs, this sixth of eight components focuses on the evaluation of students' occupational competence based on the identification of job tasks. The component makes use of existing Vocational-Technical Education…

  3. Direct numerical simulations of a turbulent separation bubble over a wide Reynolds-number range

    NASA Astrophysics Data System (ADS)

    Abe, Hiroyuki; Mizobuchi, Yasuhiro; Matsuo, Yuichi; Spalart, Philippe R.

    2015-11-01

    Direct numerical simulations (DNSs) of a turbulent boundary layer separating from a flat plate and reattaching have been performed with inlet data generated by rescaling-recycling at Reθ =300, 600 and 900. The focus is put on massive separation and the set-up close to those of Spalart & Coleman (1997) and Na & Moin (1998) at lower Reynolds number. This extends the work of Abe et al. (CTR Annual Brief, 2012) but removes the stagnation point, present over the bubble and due to strong blowing and suction Vtop at the upper boundary. The new simulations have a reduced Vtop, compensated by a smaller ceiling height. The overall agreement with the earlier DNSs is satisfactory. A small difference appears in the recovery region, in which turbulence is reduced slightly in the present DNSs. At all three Reθ , separation and reattachment locations are nearly identical. Also, the mean spanwise vorticity is conserved to a large extent along the bubble. We associate this inviscid transport with the high peak in Reynolds shear stress known to appear after reattachment, and to be a challenging phenomenon for turbulence theories and models. In the latter region, a significant Re dependence is found for the skin friction due to the weak development of near-wall turbulence.

  4. A strongly goal-directed close-range vision system for spacecraft docking

    NASA Technical Reports Server (NTRS)

    Boyer, Kim L.; Goddard, Ralph E.

    1991-01-01

    In this presentation, we will propose a strongly goal-oriented stereo vision system to establish proper docking approach motions for automated rendezvous and capture (AR&C). From an input sequence of stereo video image pairs, the system produces a current best estimate of: contact position; contact vector; contact velocity; and contact orientation. The processing demands imposed by this particular problem and its environment dictate a special case solution; such a system should necessarily be, in some sense, minimalist. By this we mean the system should construct a scene description just sufficiently rich to solve the problem at hand and should do no more processing than is absolutely necessary. In addition, the imaging resolution should be just sufficient. Extracting additional information and constructing higher level scene representations wastes energy and computational resources and injects an unnecessary degree of complexity, increasing the likelihood of malfunction. We therefore take a departure from most prior stereopsis work, including our own, and propose a system based on associative memory. The purpose of the memory is to immediately associate a set of motor commands with a set of input visual patterns in the two cameras. That is, rather than explicitly computing point correspondences and object positions in world coordinates and trying to reason forward from this information to a plan of action, we are trying to capture the essence of reflex behavior through the action of associative memory. The explicit construction of point correspondences and 3D scene descriptions, followed by online velocity and point of impact calculations, is prohibitively expensive from a computational point of view for the problem at hand. Learned patterns on the four image planes, left and right at two discrete but closely spaced instants in time, will be bused directly to infer the spacecraft reaction. This will be a continuing online process as the docking collar approaches.

  5. A strongly goal-directed close-range vision system for spacecraft docking

    NASA Astrophysics Data System (ADS)

    Boyer, Kim L.; Goddard, Ralph E.

    In this presentation, we will propose a strongly goal-oriented stereo vision system to establish proper docking approach motions for automated rendezvous and capture (AR&C). From an input sequence of stereo video image pairs, the system produces a current best estimate of: contact position; contact vector; contact velocity; and contact orientation. The processing demands imposed by this particular problem and its environment dictate a special case solution; such a system should necessarily be, in some sense, minimalist. By this we mean the system should construct a scene description just sufficiently rich to solve the problem at hand and should do no more processing than is absolutely necessary. In addition, the imaging resolution should be just sufficient. Extracting additional information and constructing higher level scene representations wastes energy and computational resources and injects an unnecessary degree of complexity, increasing the likelihood of malfunction. We therefore take a departure from most prior stereopsis work, including our own, and propose a system based on associative memory. The purpose of the memory is to immediately associate a set of motor commands with a set of input visual patterns in the two cameras. That is, rather than explicitly computing point correspondences and object positions in world coordinates and trying to reason forward from this information to a plan of action, we are trying to capture the essence of reflex behavior through the action of associative memory. The explicit construction of point correspondences and 3D scene descriptions, followed by online velocity and point of impact calculations, is prohibitively expensive from a computational point of view for the problem at hand. Learned patterns on the four image planes, left and right at two discrete but closely spaced instants in time, will be bused directly to infer the spacecraft reaction. This will be a continuing online process as the docking collar approaches.

  6. Two-directional two-dimensional modified Fisher principal component analysis: an efficient approach for thermal face verification

    NASA Astrophysics Data System (ADS)

    Wang, Ning; Li, Qiong; El-Latif, Ahmed A. Abd; Peng, Jialiang; Niu, Xiamu

    2013-04-01

    In recent years, verification based on thermal face images has been extensively studied because of its invariance to illumination and immunity to forgery. However, most of them have not given full consideration to high-verification performance and singular within-class scatter matrix problems. We propose a novel thermal face verification algorithm, which is named two-directional two-dimensional modified Fisher principal component analysis. First, two-dimensional principal component analysis (2-DPCA) is utilized to extract the optimal projective vector in the row direction. Then, 2-D modified Fisher linear discriminant analysis is implemented to overcome the singular within-class scatter matrix problem of the 2-DPCA space in the column direction. Comparative experiments on the natural visible and infrared facial expression thermal face subdatabase demonstrate that the proposed approach outperforms state-of-the-art methods in terms of verification performance.

  7. Stigma-reducing components in direct-to-consumer prescription ads: onset controllability, offset controllability, and recategorization.

    PubMed

    An, Soontae; Kang, Hannah

    2011-01-01

    This study analyzed direct-to-consumer (DTC) print ads for stigmatized illnesses from 1998 to 2008. Attribution theory and recategorization theory were used as theoretical frames to assess whether those DTC ads contained message components to reduce stigma. DTC ads for 10 stigmatized illnesses in National Geographic, Better Homes and Gardens, Ladies' Home Journal, and Time were analyzed for the presence of onset controllability, offset controllability, and recategorization. Results showed that only 3.7% of ads offered the three message components together and, in fact, 21% of the ads did not contain any of the stigma-reducing message elements. Recategorization cue was the most prevalent component, while cues for onset and offset controllability were relatively less frequent, indicating the lack of educational components. PMID:21442502

  8. In silico dissection of Type VII Secretion System components across bacteria: New directions towards functional characterization.

    PubMed

    Das, Chandrani; Ghosh, Tarini Shankar; Mande, Sharmila S

    2016-03-01

    Type VII Secretion System (T7SS) is one of the factors involved in virulence of Mycobacterium tuberculosis H37Rv. Numerous research efforts have been made in the last decade towards characterizing the components of this secretion system. An extensive genome-wide analysis through compilation of isolated information is required to obtain a global view of diverse characteristics and pathogenicity-related aspects of this machinery. The present study suggests that differences in structural components (of T7SS) between Actinobacteria and Firmicutes, observed earlier in a few organisms, is indeed a global trend. A few hitherto uncharacterized T7SS-like clusters have been identified in the pathogenic bacteria Enterococcus faecalis, Saccharomonospora viridis, Streptococcus equi, Streptococcus gordonii and Streptococcus sanguinis. Experimental verification of these clusters can shed lights on their role in bacterial pathogenesis. Similarly, verification of the identified variants of T7SS clusters consisting additional membrane components may help in unraveling new mechanism of protein translocation through T7SS. A database of various components of T7SS has been developed to facilitate easy access and interpretation of T7SS related data. PMID:26949095

  9. Multi-component molecular-level body composition reference methods: evolving concepts and future directions.

    PubMed

    Heymsfield, S B; Ebbeling, C B; Zheng, J; Pietrobelli, A; Strauss, B J; Silva, A M; Ludwig, D S

    2015-04-01

    Excess adiposity is the main phenotypic feature that defines human obesity and that plays a pathophysiological role in most chronic diseases. Measuring the amount of fat mass present is thus a central aspect of studying obesity at the individual and population levels. Nevertheless, a consensus is lacking among investigators on a single accepted 'reference' approach for quantifying fat mass in vivo. While the research community generally relies on the multi-component body volume class of 'reference' models for quantifying fat mass, no definable guide discerns among different applied equations for partitioning the four (fat, water, protein and mineral mass) or more quantified components, standardizes 'adjustment' or measurement system approaches for model-required labelled water dilution volumes and bone mineral mass estimates, or firmly establishes the body temperature at which model physical properties are assumed. The resulting differing reference strategies for quantifying body composition in vivo leads to small, but under some circumstances, important differences in the amount of measured body fat. Recent technological advances highlight opportunities to expand model applications to new subject groups and measured components such as total body protein. The current report reviews the historical evolution of multi-component body volume-based methods in the context of prevailing uncertainties and future potential. PMID:25645009

  10. Hadronic components of EAS by rigorous saddle point method in the energy range between 10(5) and 10(8) GeV

    NASA Technical Reports Server (NTRS)

    Roy, S.; Sinha, M.

    1985-01-01

    The study of hadronic components in the high energy range between 10 to the 5 and 10 to the 8 Gev exhibits by far the strongest mass sensitivity since the primary energy spectrum as discussed by Linsley and measured by many air shower experimental groups indicates a change of slope from -1.7 to 2.0 in this energy range. This change of slope may be due to several reasons such as a genuine spectral feature of astrophysical origin, a confinement effect of galactic component or a rather rapid change of mass, a problem which we have attempted to study here in detail.

  11. Direct estimation of dissolved organic carbon using synchronous fluorescence and independent component analysis (ICA): advantages of a multivariate calibration.

    PubMed

    De Almeida Brehm, Franciane; de Azevedo, Julio Cesar R; da Costa Pereira, Jorge; Burrows, Hugh D

    2015-11-01

    Dissolved organic carbon (DOC) is frequently used as a diagnostic parameter for the identification of environmental contamination in aqueous systems. Since this organic matter is evolving and decaying over time. If samples are collected under environmental conditions, some sample stabilization process is needed until the corresponding analysis can be made. This may affect the analysis results. This problem can be avoided using the direct determination of DOC. We report a study using in situ synchronous fluorescence spectra, with independent component analysis to retrieve relevant major spectral contributions and their respective component contributions, for the direct determination of DOC. Fluorescence spectroscopy is a very powerful and sensitive technique to evaluate vestigial organic matter dissolved in water and is thus suited for the analytical task of direct monitoring of dissolved organic matter in water, thus avoiding the need for the stabilization step. We also report the development of an accurate calibration model for dissolved organic carbon determinations using environmental samples of humic and fulvic acids. The method described opens the opportunity for a fast, in locus, DOC estimation in environmental or other field studies using a portable fluorescence spectrometer. This combines the benefits of the use of fresh samples, without the need of stabilizers, and also allows the interpretation of various additional spectral contributions based on their respective estimated properties. We show how independent component analysis may be used to describe tyrosine, tryptophan, humic acid and fulvic acid spectra and, thus, to retrieve the respective individual component contribution to the DOC. PMID:26497563

  12. Unimodal primary sensory cortices are directly connected by long-range horizontal projections in the rat sensory cortex

    PubMed Central

    Stehberg, Jimmy; Dang, Phat T.; Frostig, Ron D.

    2014-01-01

    Research based on functional imaging and neuronal recordings in the barrel cortex subdivision of primary somatosensory cortex (SI) of the adult rat has revealed novel aspects of structure-function relationships in this cortex. Specifically, it has demonstrated that single whisker stimulation evokes subthreshold neuronal activity that spreads symmetrically within gray matter from the appropriate barrel area, crosses cytoarchitectural borders of SI and reaches deeply into other unimodal primary cortices such as primary auditory (AI) and primary visual (VI). It was further demonstrated that this spread is supported by a spatially matching underlying diffuse network of border-crossing, long-range projections that could also reach deeply into AI and VI. Here we seek to determine whether such a network of border-crossing, long-range projections is unique to barrel cortex or characterizes also other primary, unimodal sensory cortices and therefore could directly connect them. Using anterograde (BDA) and retrograde (CTb) tract-tracing techniques, we demonstrate that such diffuse horizontal networks directly and mutually connect VI, AI and SI. These findings suggest that diffuse, border-crossing axonal projections connecting directly primary cortices are an important organizational motif common to all major primary sensory cortices in the rat. Potential implications of these findings for topics including cortical structure-function relationships, multisensory integration, functional imaging, and cortical parcellation are discussed. PMID:25309339

  13. Impact of multi-component diffusion in turbulent combustion using direct numerical simulations

    SciTech Connect

    Bruno, Claudio; Sankaran, Vaidyanathan; Kolla, Hemanth; Chen, Jacqueline H.

    2015-08-28

    This study presents the results of DNS of a partially premixed turbulent syngas/air flame at atmospheric pressure. The objective was to assess the importance and possible effects of molecular transport on flame behavior and structure. To this purpose DNS were performed at with two proprietary DNS codes and with three different molecular diffusion transport models: fully multi-component, mixture averaged, and imposing the Lewis number of all species to be unity.

  14. Spin engineering: Direct determination of the Ruderman-Kittel-Kasuya-Yosida far-field range function in ruthenium

    SciTech Connect

    Parkin, S.S.P. ); Mauri, D. )

    1991-10-01

    Oscillations in both {ital ferromagnetic} and antiferromagnetic indirect exchange coupling through Ru are directly measured. Ferromagnetic coupling is determined by {ital spin} {ital engineering} multilayered structures comprised of trilayers of Ni{sub 80}Co{sub 20}/Ru/Ni{sub 80}Co{sub 20} in which one of the Ni{sub 80}Co{sub 20} layers is strongly antiferromagnetically pinned to a Co layer. Oscillations in antiferromagnetic exchange coupling are measured in companion Ni{sub 80}Cu{sub 20}/Ru multilayers. The dependence of the exchange coupling strength on Ru thickness is well described by the Ruderman-Kittel-Kasuya-Yosida far-field range function, providing a direct measurement of this function through a transition metal.

  15. Direct measurement high resolution wide range extreme temperature optical sensor using an all-silicon carbide probe.

    PubMed

    Sheikh, Mumtaz; Riza, Nabeel A

    2009-05-01

    We propose and demonstrate a temperature sensing method using an all-silicon carbide probe that combines wavelength-tuned signal processing for coarse measurements and classical Fabry-Perot etalon peak shift for fine measurements. This method gives direct unambiguous temperature measurements with a high temperature resolution over a wide temperature range. Specifically, temperature measurements from room temperature to 1000 degrees C are experimentally demonstrated with an estimated resolution varying from 0.66 degrees C at room temperature to 0.12 degrees C at 1000 degrees C. The proposed sensor has applications in next-generation greener gas turbines for power production. PMID:19412286

  16. Direct measurements of the current-phase relation in long-range spin-triplet SFS Josephson junctions

    NASA Astrophysics Data System (ADS)

    Hamilton, David; van Harlingen, Dale; Wang, Yixing; Birge, Norman

    2015-03-01

    We present direct measurements of the current-phase relation (CPR) of Josephson junctions which use multiple ferromagnetic layers to generate long-range spin-triplet pair correlations. Using a phase-sensitive Josephson interferometry technique, we obtain the phase and temperature dependence of this spin-triplet supercurrent. We also demonstrate the use of an inductive shunt to enhance this technique at higher critical currents. Our data suggest that the current-phase relation of these junctions is harmonic in character. Further measurements are planned in order to determine the ground state phase shift of these junctions.

  17. The Intracellular Concentration of Acetyl Phosphate in Escherichia coli Is Sufficient for Direct Phosphorylation of Two-Component Response Regulators▿

    PubMed Central

    Klein, Adam H.; Shulla, Ana; Reimann, Sylvia A.; Keating, David H.; Wolfe, Alan J.

    2007-01-01

    Acetyl phosphate, the intermediate of the AckA-Pta pathway, acts as a global signal in Escherichia coli. Although acetyl phosphate clearly signals through two-component response regulators, it remains unclear whether acetyl phosphate acts as a direct phospho donor or functions through an indirect mechanism. We used two-dimensional thin-layer chromatography to measure the relative concentrations of acetyl phosphate, acetyl coenzyme A, ATP, and GTP over the course of the entire growth curve. We estimated that the intracellular concentration of acetyl phosphate in wild-type cells reaches at least 3 mM, a concentration sufficient to activate two-component response regulators via direct phosphoryl transfer. PMID:17545286

  18. Direct molecular dynamics simulation of liquid-solid phase equilibria for a three-component plasma.

    PubMed

    Hughto, J; Horowitz, C J; Schneider, A S; Medin, Zach; Cumming, Andrew; Berry, D K

    2012-12-01

    The neutron-rich isotope ²²Ne may be a significant impurity in carbon and oxygen white dwarfs and could impact how the stars freeze. We perform molecular dynamics simulations to determine the influence of ²²Ne in carbon-oxygen-neon systems on liquid-solid phase equilibria. Both liquid and solid phases are present simultaneously in our simulation volumes. We identify liquid, solid, and interface regions in our simulations using a bond angle metric. In general we find good agreement for the composition of liquid and solid phases between our MD simulations and the semianalytic model of Medin and Cumming. The trace presence of a third component, neon, does not appear to strongly impact the chemical separation found previously for two-component carbon and oxygen systems. This suggests that small amounts of ²²Ne may not qualitatively change how the material in white dwarf stars freezes. However, we do find systematically lower melting temperatures (higher Γ) in our MD simulations compared to the semianalytic model. This difference seems to grow with impurity parameter Q_{imp} and suggests a problem with simple corrections to the linear mixing rule for the free energy of multicomponent solid mixtures that is used in the semianalytic model. PMID:23368065

  19. Multi-Component Molecular-Level Body Composition Reference Methods: Evolving Concepts and Future Directions

    PubMed Central

    Heymsfield, Steven B.; Ebbeling, Cara B.; Zheng, Jolene; Pietrobelli, Angelo; Strauss, Boyd J.; Silva, Analiza M.; Ludwig, David S.

    2015-01-01

    Excess adiposity is the main phenotypic feature that defines human obesity and that plays a pathophysiological role in most chronic diseases. Measuring the amount of fat mass present is thus a central aspect of studying obesity at the individual and population levels. Nevertheless, a consensus is lacking among investigators on a single accepted “reference” approach for quantifying fat mass in vivo. While the research community generally relies on the multicomponent body-volume class of “reference” models for quantifying fat mass, no definable guide discerns among different applied equations for partitioning the four (fat, water, protein, and mineral mass) or more quantified components, standardizes “adjustment” or measurement system approaches for model-required labeled water dilution volumes and bone mineral mass estimates, or firmly establishes the body temperature at which model physical properties are assumed. The resulting differing reference strategies for quantifying body composition in vivo leads to small but under some circumstances important differences in the amount of measured body fat. Recent technological advances highlight opportunities to expand model applications to new subject groups and measured components such as total body protein. The current report reviews the historical evolution of multicomponent body volume-based methods in the context of prevailing uncertainties and future potential. PMID:25645009

  20. Direct molecular dynamics simulation of liquid-solid phase equilibria for a three-component plasma

    NASA Astrophysics Data System (ADS)

    Hughto, J.; Horowitz, C. J.; Schneider, A. S.; Medin, Zach; Cumming, Andrew; Berry, D. K.

    2012-12-01

    The neutron-rich isotope 22Ne may be a significant impurity in carbon and oxygen white dwarfs and could impact how the stars freeze. We perform molecular dynamics simulations to determine the influence of 22Ne in carbon-oxygen-neon systems on liquid-solid phase equilibria. Both liquid and solid phases are present simultaneously in our simulation volumes. We identify liquid, solid, and interface regions in our simulations using a bond angle metric. In general we find good agreement for the composition of liquid and solid phases between our MD simulations and the semianalytic model of Medin and Cumming. The trace presence of a third component, neon, does not appear to strongly impact the chemical separation found previously for two-component carbon and oxygen systems. This suggests that small amounts of 22Ne may not qualitatively change how the material in white dwarf stars freezes. However, we do find systematically lower melting temperatures (higher Γ) in our MD simulations compared to the semianalytic model. This difference seems to grow with impurity parameter Qimp and suggests a problem with simple corrections to the linear mixing rule for the free energy of multicomponent solid mixtures that is used in the semianalytic model.

  1. Performance of the Components of the XJ34-WE-32 Turbojet Engine over a Range of Engine and Flight Conditions

    NASA Technical Reports Server (NTRS)

    Mcaulay, John E; Sobolewski, Adam E; Smith, Ivan D

    1952-01-01

    Performance of the compressor, combustor, and turbine operating as integral parts of the XJ34-WE-32 turbojet engine was determined in the Lewis altitude wind tunnel over a range of altitudes from 5000 to 55,000 feet and flight Mach numbers from 0.28 to 1.05. Data were obtained for each of four exhaust-nozzle areas and are presented in graphical and tabular form.

  2. Surface modification of polypropylene battery separator by direct fluorination with different gas components

    NASA Astrophysics Data System (ADS)

    Li, Baoyin; Gao, Jie; Wang, Xu; Fan, Cong; Wang, Huina; Liu, Xiangyang

    2014-01-01

    Improvement in hydrophilicity of polypropylene (PP) separator and its stability is essential for enhancing the comprehensive performance of battery. In this study, the PP separators were surface modified by direct fluorination with F2/N2 and F2/O2/N2 gas atmosphere. The alkali absorption ratios (AARs) of these two kinds of fluorinated separators are 302.7% and 418.4%, respectively, which is about nine and twelve times than that of the virgin PP separator. At the same time, the AARs of the fluorinated separators stored for 90 days at ambient temperature in air environment still remain. The surface energy of PP separators is increased from 37.8 mN/m to 47.7 mN/m and 48.9 mN/m determined by contact angle measurement after direct fluorination. X-ray photoelectron spectroscopy (XPS) and attenuated total reflection infrared spectroscopy (ATR-FTIR) results indicate that polar groups, such as sbnd Cdbnd O(OH) and sbnd Csbnd Fx, are introduced into the polymeric structures of the two fluorinated separator surfaces. Larger quantity of polar groups, especially sbnd Cdbnd O(OH), are introduced on separator surface by the F2/O2/N2 modified route, which results in the difference of the AARs and behavior of alkali absorption. Scanning electron microscope (SEM) demonstrates that the size and shape of micropores of PP separators remain almost unchanged after direct fluorination.

  3. Very low levels of direct additive genetic variance in fitness and fitness components in a red squirrel population

    PubMed Central

    McFarlane, S Eryn; Gorrell, Jamieson C; Coltman, David W; Humphries, Murray M; Boutin, Stan; McAdam, Andrew G

    2014-01-01

    A trait must genetically correlate with fitness in order to evolve in response to natural selection, but theory suggests that strong directional selection should erode additive genetic variance in fitness and limit future evolutionary potential. Balancing selection has been proposed as a mechanism that could maintain genetic variance if fitness components trade off with one another and has been invoked to account for empirical observations of higher levels of additive genetic variance in fitness components than would be expected from mutation–selection balance. Here, we used a long-term study of an individually marked population of North American red squirrels (Tamiasciurus hudsonicus) to look for evidence of (1) additive genetic variance in lifetime reproductive success and (2) fitness trade-offs between fitness components, such as male and female fitness or fitness in high- and low-resource environments. “Animal model” analyses of a multigenerational pedigree revealed modest maternal effects on fitness, but very low levels of additive genetic variance in lifetime reproductive success overall as well as fitness measures within each sex and environment. It therefore appears that there are very low levels of direct genetic variance in fitness and fitness components in red squirrels to facilitate contemporary adaptation in this population. PMID:24963372

  4. Direct measurement of the intermolecular forces between counterion-condensed DNA double helices. Evidence for long range attractive hydration forces.

    PubMed Central

    Rau, D C; Parsegian, V A

    1992-01-01

    Rather than acting by modifying van der Waals or electrostatic double layer interactions or by directly bridging neighboring molecules, polyvalent ligands bound to DNA double helices appear to act by reconfiguring the water between macromolecular surfaces to create attractive long range hydration forces. We have reached this conclusion by directly measuring the repulsive forces between parallel B-form DNA double helices pushed together from the separations at which they have self organized into hexagonal arrays of parallel rods. For all of the wide variety of "condensing agents" from divalent Mn to polymeric protamines, the resulting intermolecular force varies exponentially with a decay rate of 1.4-1.5 A, exactly one-half that seen previously for hydration repulsion. Such behavior qualitatively contradicts the predictions of all electrostatic double layer and van der Waals force potentials previously suggested. It fits remarkably well with the idea, developed and tested here, that multivalent counterion adsorption reorganizes the water at discrete sites complementary to unadsorbed sites on the apposing surface. The measured strength and range of these attractive forces together with their apparent specificity suggest the presence of a previously unexpected force in molecular organization. Images FIGURE 1 PMID:1540693

  5. Recent standardization directions for high-speed client and line side components

    NASA Astrophysics Data System (ADS)

    Isono, Hideki

    2016-03-01

    Triggered by the recent vast demands of the information bandwidth, high speed transmission networking system, such as 100G/400G, have been developed and installed with extremely high speed. In order to lead the proper concept/design of the leading edge optical components which is applied for these high speed networking equipment, de-fact standardization bodies such as IEEE802.3/OIF have made important roles in the industry. The demands of the bandwidth will still continue to increase with endless degree, and therefore the future migration towards higher speed transceivers such as 1T class, and also towards the smaller form factor transceivers is absolutely inevitable, and to be examined.

  6. Direct Atomic-Orbital-Based Relativistic Two-Component Linear Response Method for Calculating Excited-State Fine Structures.

    PubMed

    Egidi, Franco; Goings, Joshua J; Frisch, Michael J; Li, Xiaosong

    2016-08-01

    In this work, we present a linear-response formalism of the complex two-component Hartree-Fock Hamiltonian that includes relativistic effects within the Douglas-Kroll-Hess and the Exact-Two-Component frameworks. The method includes both scalar and spin relativistic effects in the variational description of electronic ground and excited states, although it neglects the picture-change and explicit spin-orbit contributions arising from the two-electron interaction. An efficient direct formalism of solving the complex two-component response function is also presented in this work. The presence of spin-orbit couplings in the Hamiltonian and the two-component nature of the wave function and Fock operator allows the computation of excited-state zero-field splittings of systems for which relativistic effects are dominated by the one-electron term. Calculated results are compared to experimental reference values to assess the quality of the underlying approximations. The results show that the relativistic two-component linear response methods are able to capture the excited-state zero-field splittings with good agreement with experiments for the systems considered here, with all approximations exhibiting a similar performance. However, the error increases for heavy elements and for states of high orbital angular momentum, suggesting the importance of the two-electron relativistic effect in such situations. PMID:27387787

  7. Informing Water Management by Direct Use of Snow Information as Surrogate of Medium-to-Long Range Streamflow Forecast

    NASA Astrophysics Data System (ADS)

    Denaro, S.; Giuliani, M.; Castelletti, A.

    2014-12-01

    Medium-to-long range streamflow forecast provide a key assistance in anticipating hydro- climatic adverse events and prompting effective adaptation measures. For instance, accurate medium-long range streamflow forecasts have a great potential to improve water reservoir operation by enabling more efficient allocation of water volumes in time (e.g. via hedging). Unfortunately, these forecasts often lacks reliability and accuracy, especially when low-frequency climate forcing (e.g. ENSO) is not intense enough to improve the forecast lead time (e.g. in Europe), and might be computationally very demanding, In this work, we explore the direct use of both rough snow data (e.g. snow depth) and snow water equivalent estimates as surrogate of medium-to-long range streamflow forecast to inform the operation of a regulated lake. The underlying idea is that snow data contains key information on current and future water availability throughout the snow melting season that might significantly improve the operation's anticipation potential. We adopt a three step methodology: First, we compute the upper bound of the system performance by assuming perfect foresight and we assess the value of additional information as the difference between this ideal solution and current operation. Using input variable selection, we then select the most relevant snow information to explain the release trajectory associated to the upper bound operating policy. Finally, we derive the optimal policy conditioned upon the selected variables by Multi-Objecting Evolutionary Direct Policy Search. The methodology is demonstrated on the snow-dominated Lake Como river basin, in the Italian Alps. Lake Como is a regulated lake primarily used to supply water to a large cultivated area and snowmelt from May-July is the most important contribution to the creation of the seasonal storage. Results show that using raw data or simple SWE estimates can largely improve anticipation capability in the daily operation of

  8. Effect of directionality of multi-component ground motions on bridge fragility curves

    NASA Astrophysics Data System (ADS)

    Torbol, Marco

    This dissertation focuses on developing, evaluating and testing a new approach to seismic risk assessment of highway transportation networks. Throughout the years many researches have been conducted on each different step used in this dissertation. Most of these steps use a probabilistic approach for each single problem; Monte Carlo simulation is the brute force approach used by this dissertation, however some assumptions throughout the process were necessary to achieve results that could be useful to the final user, decision maker. When dealing with the damageability of an infrastructure network, it is necessary to start from the study of the damageability of each vulnerable component. For highway transportation networks subject to a seismic event bridges are the vulnerable component. With enough time, enough information and enough manpower the best approach is step by step: to build an analytical model for each bridge, to perform probabilistic seismic hazard analysis PSHA at each bridge site and to assess the seismic vulnerability of each bridge. Unfortunately, when dealing with large networks, bridges are present in hundreds or even thousands (LA-OC network has more than 3000 bridges; therefore subdivision in classes and prototyping of each class is necessary to reduce the problem to a more manageable dimension. a single prototype that represents its entire class is analyzed and its damageability is applied to the entire class. Fragility curves will be used to represents the bridges' damageability. Different contributions are developed in this dissertation; the fundamental one is the development of fragility curves with two uni-variate random variables. The first will be the Intensity Measure of the ground motion; the second will be the angle of seismic incidence from which the ground motion struck the structure. Bridges with the same damageability class, located at different places within the network will behave differently under the same earthquake scenario

  9. Direct quantification of PM{sub 2.5} fossil and biomass carbon within the Northern Front Range Air Quality Study's domain

    SciTech Connect

    Klinedinst, D.B.; Currie, L.A.

    1999-12-01

    Radiocarbon ({sup 14}C) analyses of PM{sub 2.5} (particulate matter with an aerodynamic diameter of 2.5 {micro}m or less) of both ambient and source samples from the Northern Front Range Air Quality Study (NFRAQS) in Colorado were performed. The {sup 14}C analyses were undertaken to provide direct fossil vs modern (biomass) carbon source discrimination data for a subset of summer and winter 1996--1997 samples collected within the Denver metropolitan area. Samples were prepared for {sup 14}C accelerator mass spectrometry measurements using techniques specially developed for small samples, i.e., {lt}100 {mu}g C. For the days and sampling periods analyzed the median and interquartile range of the winter blank corrected fraction of modern carbon was 23% (16--34%) at Welby and 27% (25--37%) at Brighton. The summer samples exhibited a more mixed signature with a median and interquartile range of 47% (9--70%). Source samples yielded {sup 14}C signatures consistent with expectation. The authors conclude fossil-derived sources contribute substantially in both seasons and at both locations; however, the biomass carbon component dominates episodically in the summer.

  10. Direct molecular dynamics simulation of liquid-solid phase equilibria for two-component plasmas.

    PubMed

    Schneider, A S; Hughto, J; Horowitz, C J; Berry, D K

    2012-06-01

    We determine the liquid-solid phase diagram for carbon-oxygen and oxygen-selenium plasma mixtures using two-phase molecular dynamics simulations. We identify liquid, solid, and interface regions using a bond angle metric. To study finite-size effects, we perform 27,648- and 55,296-ion simulations. To help monitor nonequilibrium effects, we calculate diffusion constants D(i). For the carbon-oxygen system we find that D(O) for oxygen ions in the solid is much smaller than D(C) for carbon ions and that both diffusion constants are 80 or more times smaller than diffusion constants in the liquid phase. There is excellent agreement between our carbon-oxygen phase diagram and that predicted by Medin and Cumming. This suggests that errors from finite-size and nonequilibrium effects are small and that the carbon-oxygen phase diagram is now accurately known. The oxygen-selenium system is a simple two-component model for more complex rapid proton capture nucleosynthesis ash compositions for an accreting neutron star. Diffusion of oxygen, in a predominantly selenium crystal, is remarkably fast, comparable to diffusion in the liquid phase. We find a somewhat lower melting temperature for the oxygen-selenium system than that predicted by Medin and Cumming. This is probably because of electron screening effects. PMID:23005226

  11. Direct molecular dynamics simulation of liquid-solid phase equilibria for two-component plasmas

    NASA Astrophysics Data System (ADS)

    Schneider, A. S.; Hughto, J.; Horowitz, C. J.; Berry, D. K.

    2012-06-01

    We determine the liquid-solid phase diagram for carbon-oxygen and oxygen-selenium plasma mixtures using two-phase molecular dynamics simulations. We identify liquid, solid, and interface regions using a bond angle metric. To study finite-size effects, we perform 27 648- and 55 296-ion simulations. To help monitor nonequilibrium effects, we calculate diffusion constants Di. For the carbon-oxygen system we find that DO for oxygen ions in the solid is much smaller than DC for carbon ions and that both diffusion constants are 80 or more times smaller than diffusion constants in the liquid phase. There is excellent agreement between our carbon-oxygen phase diagram and that predicted by Medin and Cumming. This suggests that errors from finite-size and nonequilibrium effects are small and that the carbon-oxygen phase diagram is now accurately known. The oxygen-selenium system is a simple two-component model for more complex rapid proton capture nucleosynthesis ash compositions for an accreting neutron star. Diffusion of oxygen, in a predominantly selenium crystal, is remarkably fast, comparable to diffusion in the liquid phase. We find a somewhat lower melting temperature for the oxygen-selenium system than that predicted by Medin and Cumming. This is probably because of electron screening effects.

  12. Development of Continuous, Direct Feedback Control Systems for Sintering of Metallic Components

    SciTech Connect

    Diran Apelian; Marc M. Baum

    2006-09-18

    N,N.-Ethylenebisstearimide (EBS) is one of the most commonlyused lubricants in the powder metallurgy (PM) industry in the sintering process. During sintering, the lubricated powder compacts are heat-treated to temperatures in excess of 1,200 °C thus fusing adjacent particles and yielding a part with improved mechanical strength. Delubrication commonly is achieved in the first zone of a sintering furnace by heating the part to temperatures in the 500-600 °C temperature range at a fixed rate and under controlled atmospheric conditions; this strategy minimizes defects, carbon contamination, and compact deformation. The de-lubricated part then enters the second zone (commonly in the 1200-1300 °C temperature range) for sintering. The third zone cools the sintered part at a desired rate to obtain the requisite micro-structural properties. Controlled delubrication is imperative towards achieving high quality parts for the following reasons: the elevated thermal gradient at the transition between the first and second zones can cause parts to expand rapidly and develop microscopic fissures (.blistering.); improper gas flows and belt speeds can lead to carbon deposition on the part and at the grain boundaries (sooting); delubrication products deposit throughout the furnace, even in the coolers, which are far removed from the preheating chamber, leading to significant maintenance costs; pollutants emitted in the exhaust stream of furnaces operating inefficiently are increasingly of environmental concern. In practice, lubricant removal is difficult to control, which often leads to reduced yields in PM manufacturing processes. Throughput is another important issue: process control ideally should lead to a delubrication cycle that yields defect-free parts in a minimum of furnace time, thereby increasing productivity and reducing the net energy consumption. Efficient process control requires rapid monitoring of suitable indicators, preferably gasphase products of delubrication

  13. Application of Optical Parametric Generator for Lidar Sensing of Minor Gas Components of the Atmosphere in 3-4 μm Spectral Range

    NASA Astrophysics Data System (ADS)

    Romanovskii, O. A.; Sadovnikov, S. A.; Kharchenko, O. V.; Shumskii, V. K.; Yakovlev, S. V.

    2016-07-01

    Possibility of application of a laser system with parametric light generation based on a nonlinear KTA crystal for lidar sensing of the atmosphere in the 3-4 μm spectral range is investigated. A technique for lidar measurements of gas components in the atmosphere with the use of differential absorption lidar (DIAL) and differential optical absorption spectroscopy (DOAS) method is developed. The DIAL-DOAS technique is tested for estimating the possibility of laser sensing of minor gas components in the atmosphere.

  14. Laser direct writing of 40 GHz RF components on flexible substrates

    NASA Astrophysics Data System (ADS)

    Zacharatos, F.; Iliadis, N.; Kanakis, J.; Bakopoulos, P.; Avramopoulos, H.; Zergioti, I.

    2016-05-01

    Flexible electronics have emerged as a very promising alternative of CMOS compatible electronics for a plethora of applications. Laser microfabrication techniques, such as selective laser patterning and sintering are compatible with flexible substrates and have demonstrated impressive results in the field of flexible electronic circuits and sensors. However, laser based manufacturing of radio frequency (RF) passive components or devices is still at an early stage. In this work we report on the all-laser fabrication of Silver Co-Planar Waveguides (CPWs) on polyethylene-naphthalate (PEN) substrates employing flat-top optics to achieve uniform laser fluence and thus high fabrication precision and reproducibility but also to mitigate the thermal effects of nanosecond laser pulses. The CPWs have been fabricated to match the impedance of 50 Ω ports of an Anritsu vector network analyzer operating from 40 MHz to 40 GHz. The all laser fabrication process consisted in the selective laser sintering of square dies on a Silver Nano Particle layer spin-coated on a PEN substrate followed by the selective laser patterning of the CPWs with a ns pulsed Nd:YAG laser source operating at 532 nm, according to the optimized parameters extracted from a previous studies of the authors. The CPWs have been characterized electrically at the 0.04-40 GHz regime and found to be excellent transmission lines with a 40 GHz 3 dB bandwidth, owing to the high electrical conductivity of Ag and the excellent dielectric properties of PEN. This novel process is a milestone towards the RF technology transfer to flexible electronics with low cost and specs comparable to the CMOS compatible equivalents.

  15. Direct measurements of mass-specific optical cross sections of single-component aerosol mixtures.

    PubMed

    Radney, James G; Ma, Xiaofei; Gillis, Keith A; Zachariah, Michael R; Hodges, Joseph T; Zangmeister, Christopher D

    2013-09-01

    The optical properties of atmospheric aerosols vary widely, being dependent upon particle composition, morphology, and mixing state. This diversity and complexity of aerosols motivates measurement techniques that can discriminate and quantify a variety of single- and multicomponent aerosols that are both internally and externally mixed. Here, we present a new combination of techniques to directly measure the mass-specific extinction and absorption cross sections of laboratory-generated aerosols that are relevant to atmospheric studies. Our approach employs a tandem differential mobility analyzer, an aerosol particle mass analyzer, cavity ring-down and photoacoustic spectrometers, and a condensation particle counter. This suite of instruments enables measurement of aerosol particle size, mass, extinction and absorption coefficients, and aerosol number density, respectively. Taken together, these observables yield the mass-specific extinction and absorption cross sections without the need to model particle morphology or account for sample collection artifacts. Here we demonstrate the technique in a set of case studies which involve complete separation of aerosol by charge, separation of an external mixture by mass, and discrimination between particle types by effective density and single-scattering albedo. PMID:23875772

  16. Search for the Galactic Disk and Halo Components in the Arrival Directions of High-Energy Astrophysical Neutrinos

    NASA Astrophysics Data System (ADS)

    Troitsky, S. V.

    2015-12-01

    The arrival directions of 40 neutrino events with energies ≳100 TeV, observed by the IceCube experiment, are studied. Their distribution in the Galactic latitude and in the angular distance to the Galactic Center allow searching for the Milky-Way disk and halo-related components, respectively. No statistically significant evidence for the disk component is found, though even 100% disk origin of the flux is allowed at the 90% confidence level. Contrary, the Galactic Center-Anticenter dipole anisotropy, specific for dark-matter decays (annihilation) or for interactions of cosmic rays with the extended halo of the circumgalactic gas, is clearly favored over the isotropic distribution (the probability of fluctuation of the isotropic signal is ~2%).

  17. Direct method of three-dimensional imaging using the multiple-wavelength range-gated active imaging principle.

    PubMed

    Matwyschuk, Alexis

    2016-05-10

    The tomography executed with mono-wavelength active imaging systems uses the recording of several images to restore a three-dimensional (3D) scene. Thus, in order to show the depth in the scene, a different color is attributed to each recorded image. Therefore, the 3D restoration depends on the video frame rate of the camera. By using a multiple-wavelength range-gated active imaging system, it is possible to restore the 3D scene directly in a single image at the moment of recording with a video camera. Each emitted light pulse with a different wavelength corresponds to a visualized zone at a different distance in the scene. The camera shutter opens just once during the emission of light pulses with the different wavelengths. Thus, the restoration can be executed in real time with regard to the video frame rate of the camera. From an analytical model and from a graphical approach, we demonstrated the feasibility of this new method of 3D restoration. The non-overlapping conditions between two consecutive visualized zones are analyzed. The experimental test results confirm these different conditions and validate the theoretical principle to directly restore the 3D scene in a color image with a multiple-wavelength laser source, an RGB filter, and a triggerable intensified camera. PMID:27168293

  18. Direct functional consequences of ZRS enhancer mutation combine with secondary long range SHH signalling effects to cause preaxial polydactyly

    PubMed Central

    Johnson, Edward J.; Neely, David M.; Dunn, Ian C.; Davey, Megan G.

    2014-01-01

    Sonic hedgehog (SHH) plays a central role in patterning numerous embryonic tissues including, classically, the developing limb bud where it controls digit number and identity. This study utilises the polydactylous Silkie (Slk) chicken breed, which carries a mutation in the long range limb-specific regulatory element of SHH, the ZRS. Using allele specific SHH expression analysis combined with quantitative protein analysis, we measure allele specific changes in SHH mRNA and concentration of SHH protein over time. This confirms that the Slk ZRS enhancer mutation causes increased SHH expression in the posterior leg mesenchyme. Secondary consequences of this increased SHH signalling include increased FGF pathway signalling and growth as predicted by the SHH/GREM1/FGF feedback loop and the Growth/Morphogen models. Manipulation of Hedgehog, FGF signalling and growth demonstrate that anterior-ectopic expression of SHH and induction of preaxial polydactyly is induced secondary to increased SHH signalling and Hedgehog-dependent growth directed from the posterior limb. We predict that increased long range SHH signalling acts in combination with changes in activation of SHH transcription from the Slk ZRS allele. Through analysis of the temporal dynamics of anterior SHH induction we predict a gene regulatory network which may contribute to activation of anterior SHH expression from the Slk ZRS. PMID:24907417

  19. Single-chip fully integrated direct-modulation CMOS RF transmitters for short-range wireless applications.

    PubMed

    El-Desouki, Munir M; Qasim, Syed Manzoor; BenSaleh, Mohammed; Deen, M Jamal

    2013-01-01

    Ultra-low power radio frequency (RF) transceivers used in short-range application such as wireless sensor networks (WSNs) require efficient, reliable and fully integrated transmitter architectures with minimal building blocks. This paper presents the design, implementation and performance evaluation of single-chip, fully integrated 2.4 GHz and 433 MHz RF transmitters using direct-modulation power voltage-controlled oscillators (PVCOs) in addition to a 2.0 GHz phase-locked loop (PLL) based transmitter. All three RF transmitters have been fabricated in a standard mixed-signal CMOS 0.18 µm technology. Measurement results of the 2.4 GHz transmitter show an improvement in drain efficiency from 27% to 36%. The 2.4 GHz and 433 MHz transmitters deliver an output power of 8 dBm with a phase noise of -122 dBc/Hz at 1 MHz offset, while drawing 15.4 mA of current and an output power of 6.5 dBm with a phase noise of -120 dBc/Hz at 1 MHz offset, while drawing 20.8 mA of current from 1.5 V power supplies, respectively. The PLL transmitter delivers an output power of 9 mW with a locking range of 128 MHz and consumes 26 mA from 1.8 V power supply. The experimental results demonstrate that the RF transmitters can be efficiently used in low power WSN applications. PMID:23917260

  20. A Missing Data Approach to Correct for Direct and Indirect Range Restrictions with a Dichotomous Criterion: A Simulation Study

    PubMed Central

    Pfaffel, Andreas; Kollmayer, Marlene; Schober, Barbara; Spiel, Christiane

    2016-01-01

    A recurring methodological problem in the evaluation of the predictive validity of selection methods is that the values of the criterion variable are available for selected applicants only. This so-called range restriction problem causes biased population estimates. Correction methods for direct and indirect range restriction scenarios have widely studied for continuous criterion variables but not for dichotomous ones. The few existing approaches are inapplicable because they do not consider the unknown base rate of success. Hence, there is a lack of scientific research on suitable correction methods and the systematic analysis of their accuracies in the cases of a naturally or artificially dichotomous criterion. We aim to overcome this deficiency by viewing the range restriction problem as a missing data mechanism. We used multiple imputation by chained equations to generate complete criterion data before estimating the predictive validity and the base rate of success. Monte Carlo simulations were conducted to investigate the accuracy of the proposed correction in dependence of selection ratio, predictive validity, and base rate of success in an experimental design. In addition, we compared our proposed missing data approach with Thorndike’s well-known correction formulas that have only been used in the case of continuous criterion variables so far. The results show that the missing data approach is more accurate in estimating the predictive validity than Thorndike’s correction formulas. The accuracy of our proposed correction increases as the selection ratio and the correlation between predictor and criterion increase. Furthermore, the missing data approach provides a valid estimate of the unknown base rate of success. On the basis of our findings, we argue for the use of multiple imputation by chained equations in the evaluation of the predictive validity of selection methods when the criterion is dichotomous. PMID:27019277

  1. Directed self-assembly of mesoscopic electronic components into sparse arrays with controlled orientation using diamagnetic levitation

    NASA Astrophysics Data System (ADS)

    Tkachenko, Anton; Lu, James J.-Q.

    2015-07-01

    This paper presents a directed self-assembly (DSA) approach for assembling small electronic components, such as semiconductor dies, into sparse 2D arrays using diamagnetic levitation. The dies attached to a diamagnetic layer can be levitated at a room temperature over a stage made of magnets arranged in a checkerboard pattern. By selecting a proper die design, levitation height, and vibration pattern of the magnetic stage we assemble the dies into a regular 2D array with a specific lateral and vertical orientation of the dies. The assembled dies are transferred to a receiving substrate using capillary force.

  2. Deconvolution enhanced direction of arrival estimation using 1- and 3-component seismic arrays applied to ocean induced microseisms

    NASA Astrophysics Data System (ADS)

    Gal, M.; Reading, A. M.; Ellingsen, S. P.; Koper, K. D.; Burlacu, R.; Gibbons, S. J.

    2016-04-01

    Microseisms in the period of 2 - 10 seconds are generated in deep oceans and near coastal regions. It is common for microseisms from multiple sources to arrive at the same time at a given seismometer. It is therefore desirable to be able to measure multiple slowness vectors accurately. Popular ways to estimate the direction of arrival of ocean induced microseisms are the conventional (fk) or adaptive (Capon) beamformer. These techniques give robust estimates, but are limited in their resolution capabilities and hence do not always detect all arrivals. One of the limiting factors in determining direction of arrival with seismic arrays is the array response, which can strongly influence the estimation of weaker sources. In this work, we aim to improve the resolution for weaker sources and evaluate the performance of two deconvolution algorithms, Richardson-Lucy deconvolution and a new implementation of CLEAN-PSF. The algorithms are tested with 3 arrays of different aperture (ASAR, WRA and NORSAR) using 1 month of real data each and compared with the conventional approaches. We find an improvement over conventional methods from both algorithms and the best performance with CLEAN-PSF. We then extend the CLEAN-PSF framework to 3 components and evaluate 1 year of data from the Pilbara Seismic Array (PSAR) in north-west Australia. The 3 component CLEAN-PSF analysis is capable in resolving a previously undetected Sn phase.

  3. Direct force measurements reveal that protein Tau confers short-range attractions and isoform-dependent steric stabilization to microtubules

    PubMed Central

    Chung, Peter J.; Choi, Myung Chul; Miller, Herbert P.; Feinstein, H. Eric; Raviv, Uri; Li, Youli; Wilson, Leslie; Feinstein, Stuart C.; Safinya, Cyrus R.

    2015-01-01

    Microtubules (MTs) are hollow cytoskeletal filaments assembled from αβ-tubulin heterodimers. Tau, an unstructured protein found in neuronal axons, binds to MTs and regulates their dynamics. Aberrant Tau behavior is associated with neurodegenerative dementias, including Alzheimer’s. Here, we report on a direct force measurement between paclitaxel-stabilized MTs coated with distinct Tau isoforms by synchrotron small-angle X-ray scattering (SAXS) of MT-Tau mixtures under osmotic pressure (P). In going from bare MTs to MTs with Tau coverage near the physiological submonolayer regime (Tau/tubulin-dimer molar ratio; ΦTau = 1/10), isoforms with longer N-terminal tails (NTTs) sterically stabilized MTs, preventing bundling up to PB ∼ 10,000–20,000 Pa, an order of magnitude larger than bare MTs. Tau with short NTTs showed little additional effect in suppressing the bundling pressure (PB ∼ 1,000–2,000 Pa) over the same range. Remarkably, the abrupt increase in PB observed for longer isoforms suggests a mushroom to brush transition occurring at 1/13 < ΦTau < 1/10, which corresponds to MT-bound Tau with NTTs that are considerably more extended than SAXS data for Tau in solution indicate. Modeling of Tau-mediated MT–MT interactions supports the hypothesis that longer NTTs transition to a polyelectrolyte brush at higher coverages. Higher pressures resulted in isoform-independent irreversible bundling because the polyampholytic nature of Tau leads to short-range attractions. These findings suggest an isoform-dependent biological role for regulation by Tau, with longer isoforms conferring MT steric stabilization against aggregation either with other biomacromolecules or into tight bundles, preventing loss of function in the crowded axon environment. PMID:26542680

  4. Single-Chip Fully Integrated Direct-Modulation CMOS RF Transmitters for Short-Range Wireless Applications

    PubMed Central

    El-Desouki, Munir M.; Qasim, Syed Manzoor; BenSaleh, Mohammed; Deen, M. Jamal

    2013-01-01

    Ultra-low power radio frequency (RF) transceivers used in short-range application such as wireless sensor networks (WSNs) require efficient, reliable and fully integrated transmitter architectures with minimal building blocks. This paper presents the design, implementation and performance evaluation of single-chip, fully integrated 2.4 GHz and 433 MHz RF transmitters using direct-modulation power voltage-controlled oscillators (PVCOs) in addition to a 2.0 GHz phase-locked loop (PLL) based transmitter. All three RF transmitters have been fabricated in a standard mixed-signal CMOS 0.18 μm technology. Measurement results of the 2.4 GHz transmitter show an improvement in drain efficiency from 27% to 36%. The 2.4 GHz and 433 MHz transmitters deliver an output power of 8 dBm with a phase noise of −122 dBc/Hz at 1 MHz offset, while drawing 15.4 mA of current and an output power of 6.5 dBm with a phase noise of −120 dBc/Hz at 1 MHz offset, while drawing 20.8 mA of current from 1.5 V power supplies, respectively. The PLL transmitter delivers an output power of 9 mW with a locking range of 128 MHz and consumes 26 mA from 1.8 V power supply. The experimental results demonstrate that the RF transmitters can be efficiently used in low power WSN applications. PMID:23917260

  5. Backward tracking for the study of turbulent dispersion in direct numerical simulations over a range of Reynolds numbers

    NASA Astrophysics Data System (ADS)

    Buaria, D.; Yeung, P. K.; Sawford, B. L.

    2013-11-01

    The dispersive character of turbulence is well known, and readily observed through, for example, the increase with time of the mean separation between fluid particle pairs in a Lagrangian framework. Usually, in both direct numerical simulations (DNS) and laboratory experiments, a population of fluid particles is tracked forward in time from specified initial conditions. However, from a modeling perspective, it is more important to track the particles backwards, which would help address questions about the dynamical origins of a patch of contaminant material, or a highly convoluted multi-particle cluster. In this talk we present numerical results on backward statistics obtained by sampling particle pairs of desired separation at the final time of a relatively long DNS run. The calculation essentially involves processing large datasets consisting of the complete time history of position, velocity and velocity gradients along the trajectories. Promising results on both forward and backward dispersion from up to 16 million particles have been obtained over time intervals spanning the ballistic, inertial, and diffusive ranges. This approach will allow us to study backward dispersion and relate Lagrangian studies to scalar mixing, at Taylor-scale Reynolds numbers up to 1000. Supported by NSF Grant CBET-1235906.

  6. Airborne Measurements of CO2 Column Absorption and Range Using a Pulsed Direct-Detection Integrated Path Differential Absorption Lidar

    NASA Technical Reports Server (NTRS)

    Abshire, James B.; Riris, Haris; Weaver, Clark J.; Mao, Jianping; Allan, Graham R.; Hasselbrack, William E.; Browell, Edward V.

    2013-01-01

    We report on airborne CO2 column absorption measurements made in 2009 with a pulsed direct-detection lidar operating at 1572.33 nm and utilizing the integrated path differential absorption technique. We demonstrated these at different altitudes from an aircraft in July and August in flights over four locations in the central and eastern United States. The results show clear CO2 line shape and absorption signals, which follow the expected changes with aircraft altitude from 3 to 13 km. The lidar measurement statistics were also calculated for each flight as a function of altitude. The optical depth varied nearly linearly with altitude, consistent with calculations based on atmospheric models. The scatter in the optical depth measurements varied with aircraft altitude as expected, and the median measurement precisions for the column varied from 0.9 to 1.2 ppm. The altitude range with the lowest scatter was 810 km, and the majority of measurements for the column within it had precisions between 0.2 and 0.9 ppm.

  7. Effect of short- and long-range interactions on trp rotamer populations determined by site-directed tryptophan fluorescence of tear lipocalin.

    PubMed

    Gasymov, Oktay K; Abduragimov, Adil R; Glasgow, Ben J

    2013-01-01

    In the lipocalin family, the conserved interaction between the main α-helix and the β-strand H is an ideal model to study protein side chain dynamics. Site-directed tryptophan fluorescence (SDTF) has successfully elucidated tryptophan rotamers at positions along the main alpha helical segment of tear lipocalin (TL). The rotamers assigned by fluorescent lifetimes of Trp residues corroborate the restriction expected based on secondary structure. Steric conflict constrains Trp residues to two (t, g⁻) of three possible χ₁ (t, g⁻, g⁺) canonical rotamers. In this study, investigation focused on the interplay between rotamers for a single amino acid position, Trp 130 on the α-helix and amino acids Val 113 and Leu 115 on the H strand, i.e. long range interactions. Trp130 was substituted for Phe by point mutation (F130W). Mutations at positions 113 and 115 with combinations of Gly, Ala, Phe residues alter the rotamer distribution of Trp130. Mutations, which do not distort local structure, retain two rotamers (two lifetimes) populated in varying proportions. Replacement of either long range partner with a small amino acid, V113A or L115A, eliminates the dominance of the t rotamer. However, a mutation that distorts local structure around Trp130 adds a third fluorescence lifetime component. The results indicate that the energetics of long-range interactions with Trp 130 further tune rotamer populations. Diminished interactions, evident in W130G113A115, result in about a 22% increase of α-helix content. The data support a hierarchic model of protein folding. Initially the secondary structure is formed by short-range interactions. TL has non-native α-helix intermediates at this stage. Then, the long-range interactions produce the native fold, in which TL shows α-helix to β-sheet transitions. The SDTF method is a valuable tool to assess long-range interaction energies through rotamer distribution as well as the characterization of low-populated rotameric states of

  8. Effect of Short- and Long-Range Interactions on Trp Rotamer Populations Determined by Site-Directed Tryptophan Fluorescence of Tear Lipocalin

    PubMed Central

    Gasymov, Oktay K.; Abduragimov, Adil R.; Glasgow, Ben J.

    2013-01-01

    In the lipocalin family, the conserved interaction between the main α-helix and the β-strand H is an ideal model to study protein side chain dynamics. Site-directed tryptophan fluorescence (SDTF) has successfully elucidated tryptophan rotamers at positions along the main alpha helical segment of tear lipocalin (TL). The rotamers assigned by fluorescent lifetimes of Trp residues corroborate the restriction expected based on secondary structure. Steric conflict constrains Trp residues to two (t, g−) of three possible χ1 (t, g−, g+) canonical rotamers. In this study, investigation focused on the interplay between rotamers for a single amino acid position, Trp 130 on the α-helix and amino acids Val 113 and Leu 115 on the H strand, i.e. long range interactions. Trp130 was substituted for Phe by point mutation (F130W). Mutations at positions 113 and 115 with combinations of Gly, Ala, Phe residues alter the rotamer distribution of Trp130. Mutations, which do not distort local structure, retain two rotamers (two lifetimes) populated in varying proportions. Replacement of either long range partner with a small amino acid, V113A or L115A, eliminates the dominance of the t rotamer. However, a mutation that distorts local structure around Trp130 adds a third fluorescence lifetime component. The results indicate that the energetics of long-range interactions with Trp 130 further tune rotamer populations. Diminished interactions, evident in W130G113A115, result in about a 22% increase of α-helix content. The data support a hierarchic model of protein folding. Initially the secondary structure is formed by short-range interactions. TL has non-native α-helix intermediates at this stage. Then, the long-range interactions produce the native fold, in which TL shows α-helix to β-sheet transitions. The SDTF method is a valuable tool to assess long-range interaction energies through rotamer distribution as well as the characterization of low-populated rotameric states of

  9. Path-Integral Monte Carlo Determination of the Fourth-Order Virial Coefficient for a Unitary Two-Component Fermi Gas with Zero-Range Interactions

    NASA Astrophysics Data System (ADS)

    Yan, Yangqian; Blume, D.

    2016-06-01

    The unitary equal-mass Fermi gas with zero-range interactions constitutes a paradigmatic model system that is relevant to atomic, condensed matter, nuclear, particle, and astrophysics. This work determines the fourth-order virial coefficient b4 of such a strongly interacting Fermi gas using a customized ab initio path-integral Monte Carlo (PIMC) algorithm. In contrast to earlier theoretical results, which disagreed on the sign and magnitude of b4 , our b4 agrees within error bars with the experimentally determined value, thereby resolving an ongoing literature debate. Utilizing a trap regulator, our PIMC approach determines the fourth-order virial coefficient by directly sampling the partition function. An on-the-fly antisymmetrization avoids the Thomas collapse and, combined with the use of the exact two-body zero-range propagator, establishes an efficient general means to treat small Fermi systems with zero-range interactions.

  10. Path-Integral Monte Carlo Determination of the Fourth-Order Virial Coefficient for a Unitary Two-Component Fermi Gas with Zero-Range Interactions.

    PubMed

    Yan, Yangqian; Blume, D

    2016-06-10

    The unitary equal-mass Fermi gas with zero-range interactions constitutes a paradigmatic model system that is relevant to atomic, condensed matter, nuclear, particle, and astrophysics. This work determines the fourth-order virial coefficient b_{4} of such a strongly interacting Fermi gas using a customized ab initio path-integral Monte Carlo (PIMC) algorithm. In contrast to earlier theoretical results, which disagreed on the sign and magnitude of b_{4}, our b_{4} agrees within error bars with the experimentally determined value, thereby resolving an ongoing literature debate. Utilizing a trap regulator, our PIMC approach determines the fourth-order virial coefficient by directly sampling the partition function. An on-the-fly antisymmetrization avoids the Thomas collapse and, combined with the use of the exact two-body zero-range propagator, establishes an efficient general means to treat small Fermi systems with zero-range interactions. PMID:27341213

  11. Path integral Monte Carlo determination of the fourth-order virial coefficient for unitary two-component Fermi gas with zero-range interactions

    NASA Astrophysics Data System (ADS)

    Yan, Yangqian; Blume, D.

    2016-05-01

    The unitary equal-mass Fermi gas with zero-range interactions constitutes a paradigmatic model system that is relevant to atomic, condensed matter, nuclear, particle, and astro physics. This work determines the fourth-order virial coefficient b4 of such a strongly-interacting Fermi gas using a customized ab inito path integral Monte Carlo (PIMC) algorithm. In contrast to earlier theoretical results, which disagreed on the sign and magnitude of b4, our b4 agrees with the experimentally determined value, thereby resolving an ongoing literature debate. Utilizing a trap regulator, our PIMC approach determines the fourth-order virial coefficient by directly sampling the partition function. An on-the-fly anti-symmetrization avoids the Thomas collapse and, combined with the use of the exact two-body zero-range propagator, establishes an efficient general means to treat small Fermi systems with zero-range interactions. We gratefully acknowledge support by the NSF.

  12. Survey of the response of standard limited streamer tubes over the complete range of three-component gas mixtures of isobutane, CO/sub 2/, argon

    SciTech Connect

    Calcaterra, A.; De Sangro, R.; De Simone, P.; Burrows, P.; Cartwright, S.L.; Gonzalez, S.; Lath, A.; Schneekloth, U.; Williams, D.C.; Yamartino, J.M.

    1989-07-01

    We present the results of a systematic study of three-component gas mixtures containing argon, isobutane, and carbon dioxide. The study used production-type chambers from the SLD Warm Iron Calorimeter (WIC), instrumented with standard pleastic streamert tubes, and triggered by cosmic-ray muons. Pulse height spectra are presented as a function of high voltage, over a wide range of mixtures of these three gases. Various features and similarities observed throughout this three-dimensional mixture space are important clues to understanding the underlying physics of discharge mechanisms in wire detectors. 15 refs., 17 figs.

  13. Brazing of ceramic and graphite to metal in the fabrication of ICRF (ion cyclotron range of frequencies) antenna and feedthrough components

    SciTech Connect

    Schechter, D.E.; Sluss, F.; Hoffman, D.J.

    1987-01-01

    Fabrication of some of the more critical components of ion cyclotron range of frequencies (ICRF) antenna and feedthrough assemblies has involved the brazing of alumina ceramic and graphite to various metals. Copper end pieces have been successfully brazed to alumina cylinders for use in feedthroughs for TEXTOR and in feedthroughs and capacitors for a Tokamak Fusion Test Reactor (TFTR) antenna. Copper-plated Inconel rods and tubes have been armored with graphite for construction of Faraday shields on antennas for Doublet III-D and TFTR. Details of brazing procedures and test results, including rf performance, mechanical strength, and thermal capabilities, are presented. 14 figs.

  14. Airborne Measurements of CO2 Column Concentration and Range Using a Pulsed Direct-Detection IPDA Lidar

    NASA Technical Reports Server (NTRS)

    Abshire, James B.; Ramanathan, Anand; Riris, Haris; Mao, Jianping; Allan, Graham R.; Hasselbrack, William E.; Weaver, Clark J.; Browell, Edward V.

    2013-01-01

    We have previously demonstrated a pulsed direct detection IPDA lidar to measure range and the column concentration of atmospheric CO2. The lidar measures the atmospheric backscatter profiles and samples the shape of the 1,572.33 nm CO2 absorption line. We participated in the ASCENDS science flights on the NASA DC-8 aircraft during August 2011 and report here lidar measurements made on four flights over a variety of surface and cloud conditions near the US. These included over a stratus cloud deck over the Pacific Ocean, to a dry lake bed surrounded by mountains in Nevada, to a desert area with a coal-fired power plant, and from the Rocky Mountains to Iowa, with segments with both cumulus and cirrus clouds. Most flights were to altitudes >12 km and had 5-6 altitude steps. Analyses show the retrievals of lidar range, CO2 column absorption, and CO2 mixing ratio worked well when measuring over topography with rapidly changing height and reflectivity, through thin clouds, between cumulus clouds, and to stratus cloud tops. The retrievals shows the decrease in column CO2 due to growing vegetation when flying over Iowa cropland as well as a sudden increase in CO2 concentration near a coal-fired power plant. For regions where the CO2 concentration was relatively constant, the measured CO2 absorption lineshape (averaged for 50 s) matched the predicted shapes to better than 1% RMS error. For 10 s averaging, the scatter in the retrievals was typically 2-3 ppm and was limited by the received signal photon count. Retrievals were made using atmospheric parameters from both an atmospheric model and from in situ temperature and pressure from the aircraft. The retrievals had no free parameters and did not use empirical adjustments, and >70% of the measurements passed screening and were used in analysis. The differences between the lidar-measured retrievals and in situ measured average CO2 column concentrations were <1.4 ppm for flight measurement altitudes >6 km.

  15. Characterization of magnetized ore bodies based on three-component borehole magnetic and directional borehole seismic measurements

    NASA Astrophysics Data System (ADS)

    Virgil, Christopher; Neuhaus, Martin; Hördt, Andreas; Giese, Rüdiger; Krüger, Kay; Jurczyk, Andreas; Juhlin, Christopher; Juhojuntti, Niklas

    2016-04-01

    In the last decades magnetic prospecting using total field data was used with great success for localization and characterization of ferromagnetic ore bodies. Especially borehole magnetic measurements reveal important constraints on the extent and depth of potential mining targets. However, due to the inherent ambiguity of the interpretation of magnetic data, the resulting models of the distribution of magnetized material, such as iron ore bodies, are not entirely reliable. Variations in derived parameters like volume and estimated ore content of the expected body have significant impact on the economic efficiency of a planned mine. An important improvement is the introduction of three-component borehole magnetic sondes. Modern tools comprise orientation modules which allow the continuous determination of the tool's heading regardless of the well inclination and independent of the magnetic field. Using the heading information the recorded three-component magnetic data can be transferred from the internal tool's frame to the geographic reference frame. The vector information yields a more detailed and reliable description of the ore bodies compared to total field or horizontal and vertical field data. Nevertheless complementary information to constrain the model is still advisable. The most important supplementary information for the interpretation of magnetic data is the knowledge of the structural environment of the target regions. By discriminating dissimilar rock units, a geometrical starting model can be derived, constraining the magnetic interpretation and leading to a more robust estimation of the rock magnetizations distribution. The most common approach to reveal the lithological setting rests upon seismic measurements. However, for deep drilling targets surface seismic and VSP lack the required spatial resolution of 10s of meters. A better resolution is achieved by using directed sources and receivers inside the borehole. Here we present the application of

  16. Factor analysis as a tool for spectral line component separation 21cm emission in the direction of L1780

    NASA Technical Reports Server (NTRS)

    Toth, L. V.; Mattila, K.; Haikala, L.; Balazs, L. G.

    1992-01-01

    The spectra of the 21cm HI radiation from the direction of L1780, a small high-galactic latitude dark/molecular cloud, were analyzed by multivariate methods. Factor analysis was performed on HI (21cm) spectra in order to separate the different components responsible for the spectral features. The rotated, orthogonal factors explain the spectra as a sum of radiation from the background (an extended HI emission layer), and from the L1780 dark cloud. The coefficients of the cloud-indicator factors were used to locate the HI 'halo' of the molecular cloud. Our statistically derived 'background' and 'cloud' spectral profiles, as well as the spatial distribution of the HI halo emission distribution were compared to the results of a previous study which used conventional methods analyzing nearly the same data set.

  17. Deconvolution enhanced direction of arrival estimation using one- and three-component seismic arrays applied to ocean induced microseisms

    NASA Astrophysics Data System (ADS)

    Gal, M.; Reading, A. M.; Ellingsen, S. P.; Koper, K. D.; Burlacu, R.; Gibbons, S. J.

    2016-07-01

    Microseisms in the period of 2-10 s are generated in deep oceans and near coastal regions. It is common for microseisms from multiple sources to arrive at the same time at a given seismometer. It is therefore desirable to be able to measure multiple slowness vectors accurately. Popular ways to estimate the direction of arrival of ocean induced microseisms are the conventional (fk) or adaptive (Capon) beamformer. These techniques give robust estimates, but are limited in their resolution capabilities and hence do not always detect all arrivals. One of the limiting factors in determining direction of arrival with seismic arrays is the array response, which can strongly influence the estimation of weaker sources. In this work, we aim to improve the resolution for weaker sources and evaluate the performance of two deconvolution algorithms, Richardson-Lucy deconvolution and a new implementation of CLEAN-PSF. The algorithms are tested with three arrays of different aperture (ASAR, WRA and NORSAR) using 1 month of real data each and compared with the conventional approaches. We find an improvement over conventional methods from both algorithms and the best performance with CLEAN-PSF. We then extend the CLEAN-PSF framework to three components (3C) and evaluate 1 yr of data from the Pilbara Seismic Array in northwest Australia. The 3C CLEAN-PSF analysis is capable in resolving a previously undetected Sn phase.

  18. Rapid metabolic profiling of Nicotiana tabacum defence responses against Phytophthora nicotianae using direct infrared laser desorption ionization mass spectrometry and principal component analysis

    PubMed Central

    2010-01-01

    Background Successful defence of tobacco plants against attack from the oomycete Phytophthora nicotianae includes a type of local programmed cell death called the hypersensitive response. Complex and not completely understood signaling processes are required to mediate the development of this defence in the infected tissue. Here, we demonstrate that different families of metabolites can be monitored in small pieces of infected, mechanically-stressed, and healthy tobacco leaves using direct infrared laser desorption ionization orthogonal time-of-flight mass spectrometry. The defence response was monitored for 1 - 9 hours post infection. Results Infrared laser desorption ionization orthogonal time-of-flight mass spectrometry allows rapid and simultaneous detection in both negative and positive ion mode of a wide range of naturally occurring primary and secondary metabolites. An unsupervised principal component analysis was employed to identify correlations between changes in metabolite expression (obtained at different times and sample treatment conditions) and the overall defence response. A one-dimensional projection of the principal components 1 and 2 obtained from positive ion mode spectra was used to generate a Biological Response Index (BRI). The BRI obtained for each sample treatment was compared with the number of dead cells found in the respective tissue. The high correlation between these two values suggested that the BRI provides a rapid assessment of the plant response against the pathogen infection. Evaluation of the loading plots of the principal components (1 and 2) reveals a correlation among three metabolic cascades and the defence response generated in infected leaves. Analysis of selected phytohormones by liquid chromatography electrospray ionization mass spectrometry verified our findings. Conclusion The described methodology allows for rapid assessment of infection-specific changes in the plant metabolism, in particular of phenolics, alkaloids

  19. Human CHMP6, a myristoylated ESCRT-III protein, interacts directly with an ESCRT-II component EAP20 and regulates endosomal cargo sorting.

    PubMed

    Yorikawa, Chiharu; Shibata, Hideki; Waguri, Satoshi; Hatta, Kazumi; Horii, Mio; Katoh, Keiichi; Kobayashi, Toshihide; Uchiyama, Yasuo; Maki, Masatoshi

    2005-04-01

    CHMP6 (charged multivesicular body protein 6) is a human orthologue of yeast Vps (vacuolar protein sorting) 20, a component of ESCRT (endosomal sorting complex required for transport)-III. Various CHMP6 orthologues in organisms ranging from yeast to humans contain the N-myristoylation consensus sequence at each N-terminus. Metabolic labelling of HEK-293 (human embryonic kidney) cells showed the incorporation of [3H]myristate into CHMP6 fused C-terminally to GFP (green fluorescent protein) (CHMP6-GFP). Interactions of CHMP6 with another ESCRT-III component CHMP4b/Shax [Snf7 (sucrose non-fermenting 7) homologue associated with Alix] 1, one of three paralogues of human Vps32/Snf7, and with EAP20 (ELL-associated protein 20), a human counterpart of yeast Vps25 and component of ESCRT-II, were observed by co-immunoprecipitation of epitope-tagged proteins expressed in HEK-293 cells. The in vitro pull-down assays using their recombinant proteins purified from Escherichia coli demonstrated direct physical interactions which were mediated by the N-terminal basic half of CHMP6. Overexpressed CHMP6-GFP in HeLa cells exhibited a punctate distribution throughout the cytoplasm especially in the perinuclear area, as revealed by fluorescence microscopic analysis. Accumulation of LBPA (lysobisphosphatidic acid), a major phospholipid in internal vesicles of an MVB (multivesicular body), was observed in the CHMP6-GFP-localizing area. FLAG-tagged EAP20 distributed diffusely, but exhibited a punctate distribution on co-expression with CHMP6-GFP. Overexpression of CHMP6-GFP caused reduction of transferrin receptors on the plasma membrane surface, but caused their accumulation in the cytoplasm. Ubiquitinated proteins and endocytosed EGF continuously accumulated in CHMP6-GFP-expressing cells. These results suggest that CHMP6 acts as an acceptor for ESCRT-II on endosomal membranes and regulates cargo sorting. PMID:15511219

  20. Reconstruction of limited computed tomography data of fuel cell components using Direct Iterative Reconstruction of Computed Tomography Trajectories

    NASA Astrophysics Data System (ADS)

    Lange, Axel; Kupsch, Andreas; Hentschel, Manfred P.; Manke, Ingo; Kardjilov, Nikolay; Arlt, Tobias; Grothausmann, Roman

    CT (computed tomography) reconstructions of fuel cell components of a yet unrivaled spatial resolution and quality are presented. This is achieved by application of the novel DIRECTT (Direct Iterative Reconstruction of Computed Tomography Trajectories) algorithm. We focus on two different key issues which essentially rule the fuel cell's durability on different length scales and physical interactions. On the resolution scale of some 100 μm agglomerations of condensed water in flow-field channels are detected by means of quasi- in situ neutron CT (after operation). Five orders of magnitude below nanometer sized Ru catalyst particles on carbon black support are visualized by electron tomography. Both types of experiments are especially adapted to the type of material involved but they are accompanied by severe deviations from ideal CT measuring conditions, as well. In order to overcome the tremendous reconstruction artifacts of standard algorithms, we employ DIRECTT which is described in detail. Comparisons of DIRECTT reconstructions to the conventional filtered back projection, prove the significant improvements in both experimental methods.

  1. Method of obtaining graphene and graphene-based electronic components and circuits with pencil directly on paper

    NASA Astrophysics Data System (ADS)

    Mailian, Aram; Mailian, Manvel; Shmavonyan, Gagik

    2014-03-01

    An easy method of obtaining graphene and graphene-based electronic components and circuits by drawing lines or repeatedly rubbing any type of graphite rod along the same path directly on paper and other insulating substrates is suggested. The structure containing rubbed-off layers behaves like a semiconducting material. The surface of the structure demonstrates ordered and oriented character containing few layer graphene. The carrier mobility is anisotropic through the thickness of the structure with the highest value of ~ 104 cm2/V .sec at the surface. Raman spectra of the structures in the near IR at excitation wavelength of 976 nm (1.27 eV) are registered. The observed phenomenon is universal, does not depend on the material of the substrate and could find a widespread application. For example, the junction between two rubbed off layers with different mobilities exhibits a non-Ohmic behavior. I-V characteristic of the junction is symmetrically curved with respect to 0 V. The greater is the difference between the carrier mobility, the higher is the curvature. The dynamic accumulation of the carriers in both sides of the junction creates a barrier responsible for non-Ohmic behavior.

  2. Changes in the perceived direction of drifting plaids, induced by asymmetrical changes in the spatio-temporal structure of the underlying components.

    PubMed

    Heeley, D W; Buchanan-Smith, H M

    1994-03-01

    When a plaid pattern with symmetrical velocity components (Type I) is changed to a plaid pattern with asymmetrical velocity components (Type IA), the overall direction of drift appears to undergo a rotation without any other change to the spatial parameters of the components. This change in the perceived drift direction can be induced by altering either the temporal frequency of the components or by altering their spatial frequency. In separate experiments, we have estimated the magnitude of the temporal and spatial frequency thresholds that are necessary to create a liminal change in direction of this type. The results from both temporal and spatial frequency experiments are closely similar. We find that liminal rotations can be induced by changes in the spatio-temporal structure of the sine-wave grating components that are undetectable when these components are presented in isolation. Further, we find that the "velocity threshold for direction" is not a constant factor, but critically depends on the relative orientation of the two elements that form the plaid. Forced-choice experiments were also conducted to estimate the extent of the apparent rotation of the plaid pattern for differing levels of asymmetry in the spatial frequency and temporal frequency of the components. The magnitude of the pattern rotation is predicted by a model of motion direction that encodes the successive displacements of the intersections of the gratings. Finally, we demonstrate that the velocity thresholds for perceived rotation exhibit a meridional anisotropy that depends on the direction of drift of the overall pattern and not on the orientation of the components.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8160393

  3. A Common Coordinates/Heading Direction Generation Method for a Robot Swarm with Only RSSI-Based Ranging

    NASA Astrophysics Data System (ADS)

    Hara, Shinsuke; Ishimoto, Tatsuya; Kitano, Masaya; Tsujioka, Tetsuo

    2009-12-01

    In the motion control of a microrobot swarm, a key issue is how to autonomously generate a set of common coordinates among all robots and how to notify each robot of its heading direction in the generated common coordinates without any special devices for estimating location and bearing. This paper proposes a set of common coordinates and a heading direction generation method for a robot swarm with only received signal strength indicator (RSSI) measured through wireless communications. We explain the principle of the proposed method and show some computer simulation results on the location and direction estimation errors. Finally, we demonstrate some experimental results using a swarm composed of five robots with the IEEE 802.15.4 standard as its wireless communication tool.

  4. Cooperative catalysis for the direct hydrodeoxygenation of vegetable oils into diesel-range alkanes over Pd/NbOPO4.

    PubMed

    Xia, Qineng; Zhuang, Xiaojing; Li, Molly Meng-Jung; Peng, Yung-Kang; Liu, Guoliang; Wu, Tai-Sing; Soo, Yun-Liang; Gong, Xue-Qing; Wang, Yanqin; Tsang, Shik Chi Edman

    2016-04-14

    Near quantitative carbon yields of diesel-range alkanes were achieved from the hydrodeoxygenation of triglycerides over Pd/NbOPO4 under mild conditions with no catalyst deactivation: catalyst characterization and theoretical calculations suggest that the high hydrodeoxygenation activity originated from the synergistic effect of Pd and strong Lewis acidity on the unique structure of NbOPO4. PMID:26998532

  5. Identification and assessment of groundwater flow and storage components of the relict Schöneben Rock Glacier, Niedere Tauern Range, Eastern Alps (Austria)

    NASA Astrophysics Data System (ADS)

    Winkler, Gerfried; Wagner, Thomas; Pauritsch, Marcus; Birk, Steffen; Kellerer-Pirklbauer, Andreas; Benischke, Ralf; Leis, Albrecht; Morawetz, Rainer; Schreilechner, Marcellus G.; Hergarten, Stefan

    2016-01-01

    More than 2,600 relict rock glaciers are known in the Austrian Alps but the knowledge of their hydraulic properties is severely limited. The relict Schöneben Rock Glacier (Niedere Tauern Range, Austria), with an extension of 0.17 km2, was investigated based on spring data (2006-2014) and seismic refraction survey. Spring-discharge hydrographs and natural and artificial tracer data suggest a heterogeneous aquifer with a layered internal structure for the relict rock glacier. The discharge behavior exhibits a fast and a delayed flow component. The spring discharge responds to recharge events within a few hours but a mean residence time of several months can also be observed. The internal structure of the rock glacier (up to several tens of meters thick) consists of: an upper blocky layer with a few meters of thickness, which lacks fine-grained sediments; a main middle layer with coarse and finer-grained sediments, allowing for fast flow; and an approximately 10-m-thick basal till layer as the main aquifer body responsible for the base flow. The base-flow component is controlled by (fine) sandy to silty sediments with low hydraulic conductivity and high storage capacity, exhibiting a difference in hydraulic conductivity to the upper layer of about three orders of magnitude. The high storage capacity of relict rock glaciers has an impact on water resources management in alpine catchments and potentially regulates the risk of natural hazards such as floods and related debris flows. Thus, the results highlight the importance of such aquifer systems in alpine catchments.

  6. Identification and assessment of groundwater flow and storage components of the relict Schöneben Rock Glacier, Niedere Tauern Range, Eastern Alps (Austria)

    NASA Astrophysics Data System (ADS)

    Winkler, Gerfried; Wagner, Thomas; Pauritsch, Marcus; Birk, Steffen; Kellerer-Pirklbauer, Andreas; Benischke, Ralf; Leis, Albrecht; Morawetz, Rainer; Schreilechner, Marcellus G.; Hergarten, Stefan

    2016-06-01

    More than 2,600 relict rock glaciers are known in the Austrian Alps but the knowledge of their hydraulic properties is severely limited. The relict Schöneben Rock Glacier (Niedere Tauern Range, Austria), with an extension of 0.17 km2, was investigated based on spring data (2006-2014) and seismic refraction survey. Spring-discharge hydrographs and natural and artificial tracer data suggest a heterogeneous aquifer with a layered internal structure for the relict rock glacier. The discharge behavior exhibits a fast and a delayed flow component. The spring discharge responds to recharge events within a few hours but a mean residence time of several months can also be observed. The internal structure of the rock glacier (up to several tens of meters thick) consists of: an upper blocky layer with a few meters of thickness, which lacks fine-grained sediments; a main middle layer with coarse and finer-grained sediments, allowing for fast flow; and an approximately 10-m-thick basal till layer as the main aquifer body responsible for the base flow. The base-flow component is controlled by (fine) sandy to silty sediments with low hydraulic conductivity and high storage capacity, exhibiting a difference in hydraulic conductivity to the upper layer of about three orders of magnitude. The high storage capacity of relict rock glaciers has an impact on water resources management in alpine catchments and potentially regulates the risk of natural hazards such as floods and related debris flows. Thus, the results highlight the importance of such aquifer systems in alpine catchments.

  7. Time-Variable Gravity from Satellite Laser-Ranging: The Low-Degree Components and Their Connections with Geophysical/Climatic Changes

    NASA Technical Reports Server (NTRS)

    Chao, Benjamin F.; Cox, Christopher M.

    2004-01-01

    Satellite laser-ranging (SLR) has been observing the tiny variations in Earth s global gravity for over 2 decades. The oblateness of the Earth's gravity field, J2, has been observed to undergo a secular decrease of J2 due mainly to the post-glacial rebound of the mantle. Sometime around 1998 this trend reversed quite suddenly. This reversal persisted until 2001, at which point the atmosphere-corrected time series appears to have reversed yet again towards normal. This anomaly signifies a large interannual change in global mass distribution. A number of possible causes have been considered, with oceanic mass redistribution as the leading candidate although other effects, such as glacial melting and core effects may be contributing. In fact, a strong correlation has been found between the J2 variability and the Pacific decadal oscillation. It is relatively more difficult to solve for corresponding signals in the shorter wavelength harmonics from the existing SLR-derived time variable gravity results, although it appears that geophysical fluid mass transport is being observed. For example, the recovered J3 time series shows remarkable agreement with NCEP-derived estimates of atmospheric gravity variations. Likewise, some of the non-zonal harmonic components have significant interannual signal that appears to be related to mass transport related to climatic effects such as El Nino Southern Oscillation. We will present recent updates on the J2 evolution, as well as a monthly time sequence of low-degree component map of the time-variable gravity complete through degree 4, and examine possible geophysical/climatic causes.

  8. Potential of direct metal deposition technology for manufacturing thick functionally graded coatings and parts for reactors components

    NASA Astrophysics Data System (ADS)

    Thivillon, L.; Bertrand, Ph.; Laget, B.; Smurov, I.

    2009-03-01

    Direct metal deposition (DMD) is an automated 3D deposition process arising from laser cladding technology with co-axial powder injection to refine or refurbish parts. Recently DMD has been extended to manufacture large-size near-net-shape components. When applied for manufacturing new parts (or their refinement), DMD can provide tailored thermal properties, high corrosion resistance, tailored tribology, multifunctional performance and cost savings due to smart material combinations. In repair (refurbishment) operations, DMD can be applied for parts with a wide variety of geometries and sizes. In contrast to the current tool repair techniques such as tungsten inert gas (TIG), metal inert gas (MIG) and plasma welding, laser cladding technology by DMD offers a well-controlled heat-treated zone due to the high energy density of the laser beam. In addition, this technology may be used for preventative maintenance and design changes/up-grading. One of the advantages of DMD is the possibility to build functionally graded coatings (from 1 mm thickness and higher) and 3D multi-material objects (for example, 100 mm-sized monolithic rectangular) in a single-step manufacturing cycle by using up to 4-channel powder feeder. Approved materials are: Fe (including stainless steel), Ni and Co alloys, (Cu,Ni 10%), WC compounds, TiC compounds. The developed coatings/parts are characterized by low porosity (<1%), fine microstructure, and their microhardness is close to the benchmark value of wrought alloys after thermal treatment (Co-based alloy Stellite, Inox 316L, stainless steel 17-4PH). The intended applications concern cooling elements with complex geometry, friction joints under high temperature and load, light-weight mechanical support structures, hermetic joints, tubes with complex geometry, and tailored inside and outside surface properties, etc.

  9. Progress toward creation of a Rb-87 MOT to be loaded directly into a wide-range accordion lattice

    NASA Astrophysics Data System (ADS)

    Huckans, John

    2013-05-01

    We report on our progress toward creation of a Rb-87 three-dimensional magneto-optical trap (3D MOT) to be loaded directly into an optical lattice. Preliminary calculations suggest the feasibility of achieving an approximate 102 increase in phase space density by combining standard optical molasses techniques with spatial density compression of a 3D MOT with an accordion lattice.,,, J.H. Huckans, Univ. of Maryland doctoral dissertation (2006).

  10. Direct measurement of additional Ar-H2O vibration-rotation-tunneling bands in the millimeter-submillimeter range

    NASA Astrophysics Data System (ADS)

    Zou, Luyao; Widicus Weaver, Susanna L.

    2016-06-01

    Three new weak bands of the Ar-H2O vibration-rotation-tunneling spectrum have been measured in the millimeter wavelength range. These bands were predicted from combination differences based on previously measured bands in the submillimeter region. Two previously reported submillimeter bands were also remeasured with higher frequency resolution. These new measurements allow us to obtain accurate information on the Coriolis interaction between the 101 and 110 states. Here we report these results and the associated improved molecular constants.

  11. Method and apparatus for sensing a desired component of an incident magnetic field using magneto resistive elements biased in different directions

    NASA Technical Reports Server (NTRS)

    Pant, Bharat B. (Inventor); Wan, Hong (Inventor)

    1999-01-01

    A method and apparatus for sensing a desired component of a magnetic field using an isotropic magnetoresistive material. This is preferably accomplished by providing a bias field that is parallel to the desired component of the applied magnetic field. The bias field is applied in a first direction relative to a first set of magnetoresistive sensor elements, and in an opposite direction relative to a second set of magnetoresistive sensor elements. In this configuration, the desired component of the incident magnetic field adds to the bias field incident on the first set of magnetoresistive sensor elements, and subtracts from the bias field incident on the second set of magnetoresistive sensor elements. The magnetic field sensor may then sense the desired component of the incident magnetic field by simply sensing the difference in resistance of the first set of magnetoresistive sensor elements and the second set of magnetoresistive sensor elements.

  12. Wg and Wnt4 provide long-range directional input to planar cell polarity orientation in Drosophila

    PubMed Central

    Wu, Jun; Roman, Angel-Carlos; Carvajal-Gonzalez, Jose Maria; Mlodzik, Marek

    2013-01-01

    Planar cell polarity (PCP) is cellular polarity within the plane of an epithelial tissue or organ. PCP is established through interactions of the core Frizzled(Fz)/PCP factors and although their molecular interactions are beginning to be understood, the upstream input providing directional bias/polarity axis remains unknown. Among core PCP genes, Fz is unique as it regulates PCP both cell-autonomously and non-autonomously, with the extra-cellular domain of Fz acting as a ligand for Van-Gogh (Vang). We demonstrate in Drosophila wings that Wg and dWnt4 provide instructive regulatory input for PCP axis determination, establishing polarity axes along their graded distribution and perpendicular to their expression domain borders. Loss-of-function studies reveal that Wg/dWnt4 act redundantly in PCP determination. They affect PCP by modulating the intercellular interaction between Fz and Vang, which is thought to be a key step in setting up initial polarity, thus providing directionality to the PCP process. PMID:23912125

  13. Direct Electron Heating Observed by Fast Waves in ICRF Range on a Low-Density Low Temperature Tokamak ADITYA

    SciTech Connect

    Mishra, K.; Kulkarni, S.; Rathi, D.; Varia, A.; Jadav, H.; Parmar, K.; Kadia, B.; Joshi, R.; Srinivas, Y.; Singh, R.; Kumar, S.; Dani, S.; Gayatri, A.; Yogi, R.; Singh, M.; Joisa, Y.; Rao, C.; Kumar, S.; Jha, R.; Manchanda, R.

    2011-12-23

    Fast wave electron heating experiments are carried out on Aditya tokamak [R = 0.75 m, a = 0.25m,Bt = 0.75T,ne{approx}1-3E13/cc,Te{approx}250eV] with the help of indigenously developed 200 kW, 20-40 MHz RF heating system. Significant direct electron heating is observed by fast waves in hydrogen plasma with prompt rise in electron temperature with application of RF power and it increases linearly with RF power. A corresponding increase in plasma beta and hence increase in stored diamagnetic energy is also observed in presence of RF. We observe an improvement of energy confinement time from 2-4msec during ohmic heating phase to 3-6msec in RF heating phase. This improvement is within the ohmic confinement regime for the present experiments. The impurity radiation and electron density do not escalate significantly with RF power. The direct electron heating by fast wave in Aditya is also predicted by ion cyclotron resonance heating code TORIC.

  14. A direct comparison of Ge and Si(Li) detectors in the 2--20 keV range

    SciTech Connect

    Rossington, C.S.; Giauque, R.D.; Jaklevic, J.M.

    1991-10-01

    The spectral response of high purity Ge (HPGe) and lithium-drifted Si (Si(Li)) surface barrier detectors of similar geometry has been measured over a range of x-ray energies under identical experimental conditions. Detector characteristics such as spectral background, escape peak intensity, entrance window absorption, and energy resolution are presented and compared. Although these characteristic have been discussed in the literature previously, this paper represents an attempt to consolidate the information by making comparisons under equivalent experimental conditions for the two types of detectors. A primary goal of the study is a comparison of the two types of detectors for use in x-ray fluorescence applications.

  15. Multiple ice flow directions during the Fraser Glaciation in the lower Skagit River drainage, northern Cascade Range, Washington.

    USGS Publications Warehouse

    Heller, P.L.

    1980-01-01

    Glacier reconstructions suggest that till exposed at one site in the lower Skagit Valley was deposited by a Baker Valley glacier that flowed westward down the Skagit Valley during the early part of the Fraser Glaciation (Evans Creek Stade). Stratigraphic relations show that the Cordilleran Ice Sheet subsequently advanced up the Skagit Valley and into the Baker Valley during the Vashon Stade. Flow-direction indicators, as well as clast compositional variations in till and recessional deposits of Vashon age, indicate that this upvalley, eastward-advancing glacier was later overwhelmed by south-east-flowing ice of the Cordilleran Ice Sheet which entered the Baker Valley across the valley divide to the northwest. -from Author

  16. Direct Observation of Defect Range and Evolution in Ion-Irradiated Single Crystalline Ni and Ni Binary Alloys

    NASA Astrophysics Data System (ADS)

    Lu, Chenyang; Jin, Ke; Béland, Laurent K.; Zhang, Feifei; Yang, Taini; Qiao, Liang; Zhang, Yanwen; Bei, Hongbin; Christen, Hans M.; Stoller, Roger E.; Wang, Lumin

    2016-02-01

    Energetic ions have been widely used to evaluate the irradiation tolerance of structural materials for nuclear power applications and to modify material properties. It is important to understand the defect production, annihilation and migration mechanisms during and after collision cascades. In this study, single crystalline pure nickel metal and single-phase concentrated solid solution alloys of 50%Ni50%Co (NiCo) and 50%Ni50%Fe (NiFe) without apparent preexisting defect sinks were employed to study defect dynamics under ion irradiation. Both cross-sectional transmission electron microscopy characterization (TEM) and Rutherford backscattering spectrometry channeling (RBS-C) spectra show that the range of radiation-induced defect clusters far exceed the theoretically predicted depth in all materials after high-dose irradiation. Defects in nickel migrate faster than in NiCo and NiFe. Both vacancy-type stacking fault tetrahedra (SFT) and interstitial loops coexist in the same region, which is consistent with molecular dynamics simulations. Kinetic activation relaxation technique (k-ART) simulations for nickel showed that small vacancy clusters, such as di-vacancies and tri-vacancies, created by collision cascades are highly mobile, even at room temperature. The slower migration of defects in the alloy along with more localized energy dissipation of the displacement cascade may lead to enhanced radiation tolerance.

  17. Direct Observation of Defect Range and Evolution in Ion-Irradiated Single Crystalline Ni and Ni Binary Alloys

    PubMed Central

    Lu, Chenyang; Jin, Ke; Béland, Laurent K.; Zhang, Feifei; Yang, Taini; Qiao, Liang; Zhang, Yanwen; Bei, Hongbin; Christen, Hans M.; Stoller, Roger E.; Wang, Lumin

    2016-01-01

    Energetic ions have been widely used to evaluate the irradiation tolerance of structural materials for nuclear power applications and to modify material properties. It is important to understand the defect production, annihilation and migration mechanisms during and after collision cascades. In this study, single crystalline pure nickel metal and single-phase concentrated solid solution alloys of 50%Ni50%Co (NiCo) and 50%Ni50%Fe (NiFe) without apparent preexisting defect sinks were employed to study defect dynamics under ion irradiation. Both cross-sectional transmission electron microscopy characterization (TEM) and Rutherford backscattering spectrometry channeling (RBS-C) spectra show that the range of radiation-induced defect clusters far exceed the theoretically predicted depth in all materials after high-dose irradiation. Defects in nickel migrate faster than in NiCo and NiFe. Both vacancy-type stacking fault tetrahedra (SFT) and interstitial loops coexist in the same region, which is consistent with molecular dynamics simulations. Kinetic activation relaxation technique (k-ART) simulations for nickel showed that small vacancy clusters, such as di-vacancies and tri-vacancies, created by collision cascades are highly mobile, even at room temperature. The slower migration of defects in the alloy along with more localized energy dissipation of the displacement cascade may lead to enhanced radiation tolerance. PMID:26829570

  18. Direct Observation of Defect Range and Evolution in Ion-Irradiated Single Crystalline Ni and Ni Binary Alloys.

    PubMed

    Lu, Chenyang; Jin, Ke; Béland, Laurent K; Zhang, Feifei; Yang, Taini; Qiao, Liang; Zhang, Yanwen; Bei, Hongbin; Christen, Hans M; Stoller, Roger E; Wang, Lumin

    2016-01-01

    Energetic ions have been widely used to evaluate the irradiation tolerance of structural materials for nuclear power applications and to modify material properties. It is important to understand the defect production, annihilation and migration mechanisms during and after collision cascades. In this study, single crystalline pure nickel metal and single-phase concentrated solid solution alloys of 50%Ni50%Co (NiCo) and 50%Ni50%Fe (NiFe) without apparent preexisting defect sinks were employed to study defect dynamics under ion irradiation. Both cross-sectional transmission electron microscopy characterization (TEM) and Rutherford backscattering spectrometry channeling (RBS-C) spectra show that the range of radiation-induced defect clusters far exceed the theoretically predicted depth in all materials after high-dose irradiation. Defects in nickel migrate faster than in NiCo and NiFe. Both vacancy-type stacking fault tetrahedra (SFT) and interstitial loops coexist in the same region, which is consistent with molecular dynamics simulations. Kinetic activation relaxation technique (k-ART) simulations for nickel showed that small vacancy clusters, such as di-vacancies and tri-vacancies, created by collision cascades are highly mobile, even at room temperature. The slower migration of defects in the alloy along with more localized energy dissipation of the displacement cascade may lead to enhanced radiation tolerance. PMID:26829570

  19. Direct Observation of Defect Range and Evolution in Ion-Irradiated Single Crystalline Ni and Ni Binary Alloys

    DOE PAGESBeta

    Lu, Chenyang; Jin, Ke; Béland, Laurent K.; Zhang, Feifei; Yang, Taini; Qiao, Liang; Zhang, Yanwen; Bei, Hongbin; Christen, Hans M.; Stoller, Roger E.; et al

    2016-02-01

    We report that energetic ions have been widely used to evaluate the irradiation tolerance of structural materials for nuclear power applications and to modify material properties. It is important to understand the defect production, annihilation and migration mechanisms during and after collision cascades. In this study, single crystalline pure nickel metal and single-phase concentrated solid solution alloys of 50%Ni50%Co (NiCo) and 50%Ni50%Fe (NiFe) without apparent preexisting defect sinks were employed to study defect dynamics under ion irradiation. Both cross-sectional transmission electron microscopy characterization (TEM) and Rutherford backscattering spectrometry channeling (RBS-C) spectra show that the range of radiation-induced defect clusters farmore » exceed the theoretically predicted depth in all materials after high-dose irradiation. Defects in nickel migrate faster than in NiCo and NiFe. Both vacancy-type stacking fault tetrahedra (SFT) and interstitial loops coexist in the same region, which is consistent with molecular dynamics simulations. Kinetic activation relaxation technique (k-ART) simulations for nickel showed that small vacancy clusters, such as di-vacancies and tri-vacancies, created by collision cascades are highly mobile, even at room temperature. The slower migration of defects in the alloy along with more localized energy dissipation of the displacement cascade may lead to enhanced radiation tolerance.« less

  20. Direct observation in the millisecond time range of fluorescent molecule asymmetrical interaction with the electropermeabilized cell membrane.

    PubMed Central

    Gabriel, B; Teissié, J

    1997-01-01

    Interaction of two stains (propidium iodide and ethidium bromide) with electropermeabilized living Chinese hamster ovary cells is observed using an ultrafast fluorescence image acquisition system. The computing process is linked to an ultra-low-light intensifying camera working with a very short time resolution (3.33 ms per image). Altered parts of the cell membrane were identified via the enhancement in fluorescence intensity of the dyes. They reflect the electropermeabilized part of the membrane in which free flow of dye occurred. Images of the fluorescence interaction patterns of the two dyes, in a maximum 20-ms time lag after pulsation, reveal asymmetrical permeabilization of the cell membrane. For electric field intensities higher than a first threshold value, permeabilization is always observed on the anode-facing side of the cell. For electric field intensities over a second higher threshold value, the two electrode-facing hemispheres of the cell are permeabilized, the hemisphere facing the anode being most permeable. These data support the conclusion that electropermeabilization of living cell membrane is affected by its resting potential. The asymmetrical pattern of the dye interaction is not dependent on the nature or concentration of the dye, the ionic strength of the pulsing buffer, or the duration of the pulse. The field intensity determines the fraction of the membrane in which molecular alterations can occur. The extent of alteration in this localized region is determined by the duration of the pulse when a single pulse in the millisecond time range is applied. Images FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 PMID:9370457

  1. Test Directions as a Critical Component of Test Design: Best Practices and the Impact of Examinee Characteristics

    ERIC Educational Resources Information Center

    Lakin, Joni M.

    2014-01-01

    The purpose of test directions is to familiarize examinees with a test so that they respond to items in the manner intended. However, changes in educational measurement as well as the U.S. student population present new challenges to test directions and increase the impact that differential familiarity could have on the validity of test score…

  2. Efficacy of cold-pressed terpeneless Valencia oil and its primary components on inhibition of Listeria species by direct contact and exposure to vapors.

    PubMed

    Shannon, Erin M; Milillo, Sara R; Johnson, Michael G; Ricke, Steven C

    2011-09-01

    This study used disk diffusion assays to evaluate the effectiveness of cold-pressed terpeneless Valencia oil (CPTVO) and its primary components (linalool, citral, and decanal) at inhibiting Listeria via direct contact or exposure to vapors. In general, all Listeria strains tested responded similarly to CPTVO and its components. Direct contact with linalool produced zones of inhibition that were significantly smaller (P < 0.0001) than those associated with all other antimicrobials tested. Zones of inhibition for sealed plates were significantly larger (P < 0.0001) than those observed for unsealed plates, although the method for sealing the plates was insignificant. Exposure to CPTVO vapors resulted in zones of inhibition that were significantly smaller than those resulting from decanal vapors (P < 0.0001). The difference observed between the zones of inhibition produced by antimicrobial exposure via vapors or direct contact was only slightly significant (P = 0.02). Antimicrobial essential oil (EO) vapors may be an effective alternative to direct contact EOs to safely and effectively inhibit microorganisms while minimizing undesired organoleptic changes sometimes associated with EO contact. CPTVO and its primary components, decanal and citral, may have potential in the food industry as all natural, generally recognized as safe antimicrobials used in modified atmosphere packaging designed to inhibit Listeria without requiring direct contact with food products. PMID:22417555

  3. Emission intensity in the visible and IR spectral ranges from Si-based structures formed by direct bonding with simultaneous doping with erbium (Er) and europium (Eu)

    SciTech Connect

    Mezdrogina, M. M. Kostina, L. S.; Beliakova, E. I.; Kuzmin, R. V.

    2013-09-15

    The photo- and electroluminescence spectra of silicon-based structures formed by direct bonding with simultaneous doping with rare-earth metals are studied. It is shown that emission in the visible and IR spectral ranges can be obtained from n-Si:Er/p-Si and n-Si:Eu/p-Si structures fabricated by the method suggested in the study. The results obtained make this method promising for the fabrication of optoelectronic devices.

  4. Constraints on Abundances and Compositional Ranges of X-Ray Amorphous Components in Soils and Rocks at Gale Crater from Mass Balance Calculations

    NASA Astrophysics Data System (ADS)

    Dehouck, E.; McLennan, S. M.; Meslin, P.-Y.; Cousin, A.; Rampe, E. B.; Morris, R. V.; Lanza, N. L.; Hurowitz, J. A.; Rapin, W.; MSL Science Team

    2014-07-01

    We present the results of mass balance calculations that explore the domain of possible chemical compositions (with constraints on abundances) of the amorphous component detected by Curiosity within the Rocknest and Cumberland samples.

  5. Differential effects of climate and species interactions on range limits at a hybrid zone: potential direct and indirect impacts of climate change.

    PubMed

    McQuillan, Michael A; Rice, Amber M

    2015-11-01

    The relative contributions of climate versus interspecific interactions in shaping species distributions have important implications for closely related species at contact zones. When hybridization occurs within a contact zone, these factors regulate hybrid zone location and movement. While a hybrid zone's position may depend on both climate and interactions between the hybridizing species, little is known about how these factors interact to affect hybrid zone dynamics. Here, we utilize SDM (species distribution modeling) both to characterize the factors affecting the current location of a moving North American avian hybrid zone and to predict potential direct and indirect effects of climate change on future distributions. We focus on two passerine species that hybridize where their ranges meet, the Black-capped (Poecile atricapillus) and Carolina (P. carolinensis) chickadee. Our contemporary climate models predict the occurrence of climatically suitable habitat extending beyond the hybrid zone for P. atricapillus only, suggesting that interspecific interactions primarily regulate this range boundary in P. atricapillus, while climatic factors regulate P. carolinensis. Year 2050 climate models predict a drastic northward shift in suitable habitat for P. carolinensis. Because of the greater importance of interspecific interactions for regulating the southern range limit of P. atricapillus, these climate-mediated shifts in the distribution of P. carolinensis may indirectly lead to a range retraction in P. atricapillus. Together, our results highlight the ways climate change can both directly and indirectly affect species distributions and hybrid zone location. In addition, our study lends support to the longstanding hypothesis that abiotic factors regulate species' poleward range limits, while biotic factors shape equatorial range limits. PMID:26640687

  6. Neural networks with excitatory and inhibitory components: Direct and inverse problems by a mean-field approach

    NASA Astrophysics Data System (ADS)

    di Volo, Matteo; Burioni, Raffaella; Casartelli, Mario; Livi, Roberto; Vezzani, Alessandro

    2016-01-01

    We study the dynamics of networks with inhibitory and excitatory leak-integrate-and-fire neurons with short-term synaptic plasticity in the presence of depressive and facilitating mechanisms. The dynamics is analyzed by a heterogeneous mean-field approximation, which allows us to keep track of the effects of structural disorder in the network. We describe the complex behavior of different classes of excitatory and inhibitory components, which give rise to a rich dynamical phase diagram as a function of the fraction of inhibitory neurons. Using the same mean-field approach, we study and solve a global inverse problem: reconstructing the degree probability distributions of the inhibitory and excitatory components and the fraction of inhibitory neurons from the knowledge of the average synaptic activity field. This approach unveils new perspectives on the numerical study of neural network dynamics and the possibility of using these models as a test bed for the analysis of experimental data.

  7. A multi-component domino reaction for the direct access to polyfunctionalized indoles via intermolecular allylic esterification and indolation†

    PubMed Central

    Jiang, Bo; Yi, Mian-Shuai; Shi, Feng; Pindi, Suresh; McDowell, Patrick

    2013-01-01

    A novel multi-component reaction for the synthesis of polyfunctionalized indoles and bis-indoles has been established. The reaction pathways were controlled by varying enamines with different substitution patterns to give polyfunctionalized indoles and bis-indoles selectively. The reaction proceeds at a fast speed within 15–30 min with water as the major byproduct, which makes work-up convenient. PMID:22038299

  8. Low cost 112 G direct detection metro transmission system with reduced bandwidth (10 G) components and MLSE compensation

    NASA Astrophysics Data System (ADS)

    Gorshtein, Albert; Sadot, Dan; Sheffi, Nir; Sonkin, Eduard; Shachaf, Yuval; Becker, Don; Levy, Omri; Katz, Gilad

    2015-03-01

    We experimentally demonstrate a 100 G ADC-MLSE-based 4-lanes NRZ direct detection transceiver. The DSP engine enables the use of low cost 10 G optoelectronics and supports 40 km metro transmission suitable for both ASE limited and point-to-point applications. The fully implemented mixed signal ASIC is based on standard 65 nm CMOS process.

  9. Laboratory directed research and development final report: Intelligent tools for on-machine acceptance of precision machined components

    SciTech Connect

    Christensen, N.G.; Harwell, L.D.; Hazelton, A.

    1997-02-01

    On-Machine Acceptance (OMA) is an agile manufacturing concept being developed for machine tools at SNL. The concept behind OMA is the integration of product design, fabrication, and qualification processes by using the machining center as a fabrication and inspection tool. This report documents the final results of a Laboratory Directed Research and Development effort to qualify OMA.

  10. Directional location of buried objects using three component magnetic borehole data demonstrated for the case of a drillstring

    NASA Astrophysics Data System (ADS)

    Ehmann, S.; Virgil, C.; Hördt, A.; Leven, M.

    2016-04-01

    One of the main applications of magnetic field measurements in boreholes is the detection of unexploded ordnance or buried utility structures like pipes or tiebacks. Even though the advantage of fully oriented magnetic vector measurements have long been recognised and could significantly reduce costs and risks, the tools used for those purposes typically measure only the total magnetic field, the vertical and horizontal components or gradients thereof. The Göttingen Bohrloch Magnetometer (GBM) uses three fiber optic gyros to record its orientation and thus enables us to compute high quality three component magnetic vector data regardless of borehole orientation. The measurements described in this paper were run in the scientific borehole Cuxhaven Lüdingworth 1/1A, which was drilled as a part of the "Coastal Aquifer Test field" project to study the dynamics of the saltwater/freshwater interface. As the drillstring got stuck during drilling of the first borehole, a second hole was drilled in the immediate vicinity. The drillstring lies at a depth between 80 m and 114 m at a distance of only 2.5 m south-east of the borehole used for the measurements, making it an ideal target to demonstrate the benefits of vector magnetic surveys. Although the theories to calculate magnetic fields of objects with different shapes is well established and do not need to be tested, they almost exclusively include approximations of the geometry. It is not obvious whether these approximations are suited to describe real data, or whether additional effects or refinements have to be considered. We use both a simplified monopole model and a cylinder model to fit the data and are able to determine the position of the drillstring within a statistical error of approximately 10 cm. Additionally, we show that the location of the drillstring could not have been determined by measurements of the total field or its horizontal and vertical component alone and that those methods would require the

  11. Directional location of buried objects using three-component magnetic borehole data demonstrated for the case of a drill string

    NASA Astrophysics Data System (ADS)

    Ehmann, S.; Virgil, C.; Hördt, A.; Leven, M.

    2016-06-01

    One of the main applications of magnetic field measurements in boreholes is the detection of unexploded ordnance or buried utility structures like pipes or tiebacks. Even though the advantage of fully oriented magnetic vector measurements have long been recognized and could significantly reduce costs and risks, the tools used for those purposes typically measure only the total magnetic field, the vertical and horizontal components or gradients thereof. The Göttingen Bohrloch Magnetometer uses three fibre optic gyros to record its orientation and thus enables us to compute high-quality three-component magnetic vector data regardless of borehole orientation. The measurements described in this paper were run in the scientific borehole Cuxhaven Lüdingworth 1/1A, which was drilled as a part of the `Coastal Aquifer Test field' project to study the dynamics of the saltwater/freshwater interface. As the drill string got stuck during drilling of the first borehole, a second hole was drilled in the immediate vicinity. The drill string lies at a depth between 80 and 114 m at a distance of only 2.5 m southeast of the borehole used for the measurements, making it an ideal target to demonstrate the benefits of vector magnetic surveys. Although the theories to calculate magnetic fields of objects with different shapes is well established and do not need to be tested, they almost exclusively include approximations of the geometry. It is not obvious whether these approximations are suited to describe real data, or whether additional effects or refinements have to be considered. We use both a simplified monopole model and a cylinder model to fit the data and are able to determine the position of the drill string within a statistical error of approximately 10 cm. Additionally, we show that the location of the drill string could not have been determined by measurements of the total field or its horizontal and vertical component alone and that those methods would require the drilling

  12. Direct MOVPE growth of semipolar (11 2 bar 2) AlxGa1-xN across the alloy composition range

    NASA Astrophysics Data System (ADS)

    Hatui, Nirupam; Rahman, A. Azizur; Maliakkal, Carina B.; Bhattacharya, Arnab

    2016-03-01

    We report a simple direct route for the synthesis of high-quality semipolar (11 2 bar 2) AlGaN alloys across the composition range by metalorganic vapour phase epitaxy. We show that a single high-temperature growth step without the use of a low-temperature nucleation or buffer layer is a convenient way to grow high-quality (11 2 bar 2) AlGaN layers on m-plane sapphire substrate. We also report a detailed investigation of the microstructure and optical properties of these layers including phase-purity, surface morphology, epilayer tilt, and polarization-resolved optical transmission measurements.

  13. A Distinct Subpopulation of Bone Marrow Mesenchymal Stem Cells, Muse Cells, Directly Commit to the Replacement of Liver Components.

    PubMed

    Katagiri, H; Kushida, Y; Nojima, M; Kuroda, Y; Wakao, S; Ishida, K; Endo, F; Kume, K; Takahara, T; Nitta, H; Tsuda, H; Dezawa, M; Nishizuka, S S

    2016-02-01

    Genotyping graft livers by short tandem repeats after human living-donor liver transplantation (n = 20) revealed the presence of recipient or chimeric genotype cases in hepatocytes (6 of 17, 35.3%), sinusoidal cells (18 of 18, 100%), cholangiocytes (15 of 17, 88.2%) and cells in the periportal areas (7 of 8, 87.5%), suggesting extrahepatic cell involvement in liver regeneration. Regarding extrahepatic origin, bone marrow mesenchymal stem cells (BM-MSCs) have been suggested to contribute to liver regeneration but compose a heterogeneous population. We focused on a more specific subpopulation (1-2% of BM-MSCs), called multilineage-differentiating stress-enduring (Muse) cells, for their ability to differentiate into liver-lineage cells and repair tissue. We generated a physical partial hepatectomy model in immunodeficient mice and injected green fluorescent protein (GFP)-labeled human BM-MSC Muse cells intravenously (n = 20). Immunohistochemistry, fluorescence in situ hybridization and species-specific polymerase chain reaction revealed that they integrated into regenerating areas and expressed liver progenitor markers during the early phase and then differentiated spontaneously into major liver components, including hepatocytes (≈74.3% of GFP-positive integrated Muse cells), cholangiocytes (≈17.7%), sinusoidal endothelial cells (≈2.0%), and Kupffer cells (≈6.0%). In contrast, the remaining cells in the BM-MSCs were not detected in the liver for up to 4 weeks. These results suggest that Muse cells are the predominant population of BM-MSCs that are capable of replacing major liver components during liver regeneration. PMID:26663569

  14. Lead induction of crop dysfunction in pigeons through a direct action on neural or smooth muscle components of crop tissue.

    PubMed

    Boyer, I J; Cory-Slechta, D A; DiStefano, V

    1985-09-01

    Lead acetate solutions administered p.o. to pigeons produce crop stasis. Crop dysfunction may be an indirect effect on crop activity by a direct interaction with the cerebellum or some other site associated with lead-induced ataxia. Alternatively, crop stasis may be due to the direct interaction of lead with sites on the smooth muscle or neural elements in crop tissue. A behavioral test for ataxia was performed on pigeons given lead by crop intubation or i.m. injection. Blood lead concentrations were also monitored. Lead-induced ataxia was separable from lead-induced crop dysfunction depending on the route of lead administration, suggesting that lead-induced crop stasis is not secondary to toxicity at a site associated with ataxia. Intramuscular treatment produced crop stasis more readily than did crop intubation. This probably reflects different mechanisms of absorption and metabolism. A Tris-succinate medium was devised which accommodated the solubility characteristics of lead, permitting studies of crop tissue in vitro. Lead chloride added to crop tissue in tris-succinate medium caused a concentration-related reversible relaxation. Crop circular muscle was more sensitive to Pb++ than was longitudinal muscle, in agreement with the effects of other agonists. The EC30 of crop circular smooth muscle in plasma was 1000 microM PbCl2 compared to 3 microM in Tris-succinate medium. The results suggest that lead induces crop dysfunction by acting either directly on crop smooth muscle or on neural elements in crop tissue. PMID:2993587

  15. Application of the Superslow Relaxation Model in the Description of Time Series of the Vertical Electric Field Component in the Earth's Atmospheric Boundary Layer in the Infra-Low Frequency Range

    NASA Astrophysics Data System (ADS)

    Isakevich, D. V.; Grunskaya, L. V.

    2015-12-01

    To explain the presence of spectrally localized, mutually uncorrelated the electric field components in the Earth's atmospheric boundary layer in the infra-low frequency range, it is proposed to use the model of fractionally integrated white Gaussian noise. It is shown that the uncorrelated components of the fractionally integrated (of order 0.5) white Gaussian noise have a coherence index close to that of the uncorrelated components of time series of the electric field. The energy distribution of the uncorrelated components of the fractionally integrated noise is also close to the energy distribution of the components of the electric field. To lay the basis for a physical interpretation of fractionally integrated noise, it is proposed to use the differential equation of superslow relaxation.

  16. Paired-End Sequencing of Long-Range DNA Fragments for De Novo Assembly of Large, Complex Mammalian Genomes by Direct Intra-Molecule Ligation

    PubMed Central

    Wu, Kui; Cai, Qingle; Wang, Yu; Lang, Yongshan; Cao, Hongzhi; Yang, Huangming; Wang, Jian; Zhang, Xiuqing

    2012-01-01

    Background The relatively short read lengths from next generation sequencing (NGS) technologies still pose a challenge for de novo assembly of complex mammal genomes. One important solution is to use paired-end (PE) sequence information experimentally obtained from long-range DNA fragments (>1 kb). Here, we characterize and extend a long-range PE library construction method based on direct intra-molecule ligation (or molecular linker-free circularization) for NGS. Results We found that the method performs stably for PE sequencing of 2- to 5- kb DNA fragments, and can be extended to 10–20 kb (and even in extremes, up to ∼35 kb). We also characterized the impact of low quality input DNA on the method, and develop a whole-genome amplification (WGA) based protocol using limited input DNA (<1 µg). Using this PE dataset, we accurately assembled the YanHuang (YH) genome, the first sequenced Asian genome, into a scaffold N50 size of >2 Mb, which is over100-times greater than the initial size produced with only small insert PE reads(17 kb). In addition, we mapped two 7- to 8- kb insertions in the YH genome using the larger insert sizes of the long-range PE data. Conclusions In conclusion, we demonstrate here the effectiveness of this long-range PE sequencing method and its use for the de novo assembly of a large, complex genome using NGS short reads. PMID:23029438

  17. A Direct Link between Abscisic Acid Sensing and the Chromatin-Remodeling ATPase BRAHMA via Core ABA Signaling Pathway Components.

    PubMed

    Peirats-Llobet, Marta; Han, Soon-Ki; Gonzalez-Guzman, Miguel; Jeong, Cheol Woong; Rodriguez, Lesia; Belda-Palazon, Borja; Wagner, Doris; Rodriguez, Pedro L

    2016-01-01

    Optimal response to drought is critical for plant survival and will affect biodiversity and crop performance during climate change. Mitotically heritable epigenetic or dynamic chromatin state changes have been implicated in the plant response to the drought stress hormone abscisic acid (ABA). The Arabidopsis SWI/SNF chromatin-remodeling ATPase BRAHMA (BRM) modulates response to ABA by preventing premature activation of stress response pathways during germination. We show that core ABA signaling pathway components physically interact with BRM and post-translationally modify BRM by phosphorylation/dephosphorylation. Genetic evidence suggests that BRM acts downstream of SnRK2.2/2.3 kinases, and biochemical studies identified phosphorylation sites in the C-terminal region of BRM at SnRK2 target sites that are evolutionarily conserved. Finally, the phosphomimetic BRM(S1760D S1762D) mutant displays ABA hypersensitivity. Prior studies showed that BRM resides at target loci in the ABA pathway in the presence and absence of the stimulus, but is only active in the absence of ABA. Our data suggest that SnRK2-dependent phosphorylation of BRM leads to its inhibition, and PP2CA-mediated dephosphorylation of BRM restores the ability of BRM to repress ABA response. These findings point to the presence of a rapid phosphorylation-based switch to control BRM activity; this property could be potentially harnessed to improve drought tolerance in plants. PMID:26499068

  18. {sup 63}Cu and {sup 197}Au nuclear quadrupole moments from four-component relativistic density-functional calculations using correct long-range exchange

    SciTech Connect

    Thierfelder, Christian; Schwerdtfeger, Peter; Saue, Trond

    2007-09-15

    The electric field gradient in late transition metal compounds is incorrectly determined by most density functionals. We show that the coupling of short-range density functional based with long-range wave function based methods using a reparametrization of the Coulomb-attenuated Becke three-parameter Lee-Yang-Parr approximation gives reliable results for the electric field gradients of copper and gold for a series of compounds. This results in nuclear quadrupole moments of -0.208 b for {sup 63}Cu and +0.526 b for {sup 197}Au in good agreement with experimental values of -0.220(15) and +0.547(16)b, respectively.

  19. High-momentum components of the nuclear wave function: Short range correlations, EMC effect, and the tensor parts of the N-N interaction

    SciTech Connect

    Eli Piasetzky

    2012-09-01

    The combination of inclusive and exclusive electron scattering data from JLab in kinematic regimes that were not reachable before, together with the analysis and interpretation of older data from hadronic reactions at BNL is finally revealing the details of short-range nucleon-nucleon correlations in nuclei. The most significant result is the demonstration of the dominance of correlated np pairs over pp and nn pairs. I will review these results, discuss them in terms of short-range tensor-force dominance and also discuss the connection to the EMC effect.

  20. Olive leaf components apigenin 7-glucoside and luteolin 7-glucoside direct human hematopoietic stem cell differentiation towards erythroid lineage.

    PubMed

    Samet, Imen; Villareal, Myra O; Motojima, Hideko; Han, Junkyu; Sayadi, Sami; Isoda, Hiroko

    2015-06-01

    The generation of blood cellular components from hematopoietic stem cells is important for the therapy of a broad spectrum of hematological disorders. In recent years, several lines of evidence suggested that certain nutrients, vitamins and flavonoids may have important roles in controlling the stem cell fate decision by maintaining their self-renewal or stimulating the lineage-specific differentiation. In this study, main olive leaf phytochemicals oleuropein (Olp), apigenin 7-glucoside (Api7G) and luteolin 7-glucoside (Lut7G) were investigated for their potential effects on hematopoietic stem cell differentiation using both phenotypic and molecular analysis. Oleuropein and the combination of the three compounds enhanced the differentiation of CD34+ cells into myelomonocytic cells and lymphocytes progenitors and inhibited the commitment to megakaryocytic and erythroid lineages. Treatment with Lut7G stimulated both the erythroid and the myeloid differentiation, while treatment with Api7G specifically induced the differentiation of CD34+ cells towards the erythroid lineage and inhibited the myeloid differentiation. Erythroid differentiation induced by Api7G and Lut7G treatments was confirmed by the increase in hemoglobin genes expressions (α-hemoglobin, β-hemoglobin and γ-hemoglobin) and erythroid transcription factor GATA1 expression. As revealed by microarray analysis, the mechanisms underlying the erythroid differentiation-inducing effect of Api7G on hematopoietic stem cells involves the activation of JAK/STAT signaling pathway. These findings prove the differentiation-inducing effects of olive leaf compounds on hematopoietic stem cells and highlight their potential use in the ex vivo generation of blood cells. PMID:26299581

  1. Salicylic Acid Inhibits the Replication of Tomato bushy stunt virus by Directly Targeting a Host Component in the Replication Complex.

    PubMed

    Tian, Miaoying; Sasvari, Zsuzsanna; Gonzalez, Paulina Alatriste; Friso, Giulia; Rowland, Elden; Liu, Xiao-Min; van Wijk, Klaas J; Nagy, Peter D; Klessig, Daniel F

    2015-04-01

    Although the plant hormone salicylic acid (SA) plays a central role in signaling resistance to viral infection, the underlying mechanisms are only partially understood. Identification and characterization of SA's direct targets have been shown to be an effective strategy for dissecting the complex SA-mediated defense signaling network. In search of additional SA targets, we previously developed two sensitive approaches that utilize SA analogs in conjunction with either a photoaffinity labeling technique or surface plasmon resonance-based technology to identify and evaluate candidate SA-binding proteins (SABPs) from Arabidopsis. Using these approaches, we have now identified several members of the Arabidopsis glyceraldehyde 3-phosphate dehydrogenase (GAPDH) protein family, including two chloroplast-localized and two cytosolic isoforms, as SABPs. Cytosolic GAPDH is a well-known glycolytic enzyme; it also is an important host factor involved in the replication of Tomato bushy stunt virus (TBSV), a single-stranded RNA virus. Using a yeast cell-free extract, an in vivo yeast replication system, and plant protoplasts, we demonstrate that SA inhibits TBSV replication. SA does so by inhibiting the binding of cytosolic GAPDH to the negative (-)RNA strand of TBSV. Thus, this study reveals a novel molecular mechanism through which SA regulates virus replication. PMID:25584724

  2. Helium heater design for the helium direct cycle component test facility. [for gas-cooled nuclear reactor power plant

    NASA Technical Reports Server (NTRS)

    Larson, V. R.; Gunn, S. V.; Lee, J. C.

    1975-01-01

    The paper describes a helium heater to be used to conduct non-nuclear demonstration tests of the complete power conversion loop for a direct-cycle gas-cooled nuclear reactor power plant. Requirements for the heater include: heating the helium to a 1500 F temperature, operating at a 1000 psia helium pressure, providing a thermal response capability and helium volume similar to that of the nuclear reactor, and a total heater system helium pressure drop of not more than 15 psi. The unique compact heater system design proposed consists of 18 heater modules; air preheaters, compressors, and compressor drive systems; an integral control system; piping; and auxiliary equipment. The heater modules incorporate the dual-concentric-tube 'Variflux' heat exchanger design which provides a controlled heat flux along the entire length of the tube element. The heater design as proposed will meet all system requirements. The heater uses pressurized combustion (50 psia) to provide intensive heat transfer, and to minimize furnace volume and heat storage mass.

  3. Direct-path acoustic ranging across the Japan Trench axis, Adjacent to the Large Shallow Thrusting in the 2011 Tohoku-Oki earthquake

    NASA Astrophysics Data System (ADS)

    Osada, Y.; Kido, M.; Ito, Y.; Iinuma, T.; Fujimoto, H.; Hino, R.

    2014-12-01

    Seafloor geodetic data, i.e. GPS/acoustic measurement and continuous seafloor pressure monitoring, brought important evidences showing that the 2011 Tohoku-oki earthquake (Mw 9.0) caused huge (> 50 m) coseismic slip near the Japan Trench. The postseismic behavior of the large slipped area is required to clarify to understand why large amount seismic slip could occur there. We started making direct-path acoustic ranging across the trench axis to reveal the convergence rate between the subducting Pacific and overriding continental plates. We expect the change of the baseline length across the trench axis, the plate boundary, reflects the slip rate at the shallow megathrust, which is difficult to estimate only from other geodetic observations largely affected by intraplate deformation caused by the postseismic viscoelastic relaxation process.  To this end, we developed an ultra-deep seafloor acoustic ranging system. Our previous ranging systems have been designed to measure baseline length ~ 1 km and to be deployed up to 7,000 m water-depth (Osada et al., 2008, 2012). In order to realize the measurement across the Japan Trench, we improved this system to enhance range of acoustic ranging as well as operational depth of instruments. The improved system was designed to allow acoustic ranging up to 3 km and to be durable under the high-pressure equivalent to water depth of 9,000 m. In May 2013, we carried out a test deployment of the new ranging system. The system is composed of three seafloor instruments equipped with precision transponder (PXPs). Two of the PXPs were set on the landward slope of the Japan Trench, where large coseismic slip happened in 2011. Another PXP was deployed on the seaward side of the trench so that the baseline change associated with the slip on the plate boundary fault, if any, can be detected. Continuous records of baseline lengths were successfully obtained for four months. The repeatability of the distance measurements was about 20 mm for

  4. Two Components of the RNA-Directed DNA Methylation Pathway Associate with MORC6 and Silence Loci Targeted by MORC6 in Arabidopsis

    PubMed Central

    Liu, Zhang-Wei; Zhou, Jin-Xing; Huang, Huan-Wei; Li, Yong-Qiang; Shao, Chang-Rong; Li, Lin; Cai, Tao; Chen, She

    2016-01-01

    The SU(VAR)3-9 homolog SUVH9 and the double-stranded RNA-binding protein IDN2 were thought to be components of an RNA-directed DNA methylation (RdDM) pathway in Arabidopsis. We previously found that SUVH9 interacts with MORC6 but how the interaction contributes to transcriptional silencing remains elusive. Here, our genetic analysis indicates that SUVH2 and SUVH9 can either act in the same pathway as MORC6 or act synergistically with MORC6 to mediate transcriptional silencing. Moreover, we demonstrate that IDN2 interacts with MORC6 and mediates the silencing of a subset of MORC6 target loci. Like SUVH2, SUVH9, and IDN2, other RdDM components including Pol IV, Pol V, RDR2, and DRM2 are also required for transcriptional silencing at a subset of MORC6 target loci. MORC6 was previously shown to mediate transcriptional silencing through heterochromatin condensation. We demonstrate that the SWI/SNF chromatin-remodeling complex components SWI3B, SWI3C, and SWI3D interact with MORC6 as well as with SUVH9 and then mediate transcriptional silencing. These results suggest that the RdDM components are involved not only in DNA methylation but also in MORC6-mediated heterochromatin condensation. This study illustrates how DNA methylation is linked to heterochromatin condensation and thereby enhances transcriptional silencing at methylated genomic regions. PMID:27171427

  5. Two Components of the RNA-Directed DNA Methylation Pathway Associate with MORC6 and Silence Loci Targeted by MORC6 in Arabidopsis.

    PubMed

    Liu, Zhang-Wei; Zhou, Jin-Xing; Huang, Huan-Wei; Li, Yong-Qiang; Shao, Chang-Rong; Li, Lin; Cai, Tao; Chen, She; He, Xin-Jian

    2016-05-01

    The SU(VAR)3-9 homolog SUVH9 and the double-stranded RNA-binding protein IDN2 were thought to be components of an RNA-directed DNA methylation (RdDM) pathway in Arabidopsis. We previously found that SUVH9 interacts with MORC6 but how the interaction contributes to transcriptional silencing remains elusive. Here, our genetic analysis indicates that SUVH2 and SUVH9 can either act in the same pathway as MORC6 or act synergistically with MORC6 to mediate transcriptional silencing. Moreover, we demonstrate that IDN2 interacts with MORC6 and mediates the silencing of a subset of MORC6 target loci. Like SUVH2, SUVH9, and IDN2, other RdDM components including Pol IV, Pol V, RDR2, and DRM2 are also required for transcriptional silencing at a subset of MORC6 target loci. MORC6 was previously shown to mediate transcriptional silencing through heterochromatin condensation. We demonstrate that the SWI/SNF chromatin-remodeling complex components SWI3B, SWI3C, and SWI3D interact with MORC6 as well as with SUVH9 and then mediate transcriptional silencing. These results suggest that the RdDM components are involved not only in DNA methylation but also in MORC6-mediated heterochromatin condensation. This study illustrates how DNA methylation is linked to heterochromatin condensation and thereby enhances transcriptional silencing at methylated genomic regions. PMID:27171427

  6. Effects of environmental factors on corrosion behaviors of metal-fiber porous components in a simulated direct methanol fuel cell environment

    NASA Astrophysics Data System (ADS)

    Yuan, Wei; Zhou, Bo; Tang, Yong; Zhang, Zhao-chun; Deng, Jun

    2014-09-01

    To enable the use of metallic components in direct methanol fuel cells (DMFCs), issues related to corrosion resistance must be considered because of an acid environment induced by the solid electrolyte. In this study, we report the electrochemical behaviors of metal-fiber-based porous sintered components in a simulated corrosive environment of DMFCs. Three materials were evaluated: pure copper, AISI304, and AISI316L. The environmental factors and related mechanisms affecting the corrosion behaviors were analyzed. The results demonstrated that AISI316L exhibits the best performance. A higher SO{4/2-} concentration increases the risk of material corrosion, whereas an increase in methanol concentration inhibits corrosion. The morphological features of the corroded samples were also characterized in this study.

  7. Three-dimensional visual modeling and virtual view synthesis: A synergetic, range-space stereo approach using omni-directional images

    NASA Astrophysics Data System (ADS)

    Ng, Kim Chai

    Robust depth extraction, which involves matching using passive visual cues, is a long-standing difficult problem, even when multiple cameras are employed. When both depth and color are recovered simultaneously, the difficulty level increases further. This dissertation simultaneously estimates depth and color of objects in the scene at arbitrary viewpoint by efficient range-space based multiple wide-baseline omni-directional stereo. Success will enable multiple different concurrent virtual walkthroughs being generated in a distributed manner. The research addresses five major challenges of wide- baseline omni-directional stereo: scaling effect, foreshortening effect, window distortion, specular highlight, and occlusion. Our algorithms perform searching, matching, and rendering in the range space starting from the specified viewpoint. When searching in the range space, it enables arbitrary disparate multi- camera configurations and it helps overcome the first three challenges. Cameras are selected through robust statistics to lessen the effects of specular highlight and occlusion. Area-based color match and area-based color-edge match are performed in parallel for every virtual pixel. Attributes derived from both matching curves are combined to detect a more confident voxel. A confident voxel is the one with the global color match and the global edge match at the same 3D location. These more confident matches compete to influence their 8-neighbors' 3D and color. Low confident matching regions (with high matching error), where either occlusion or specular highlight occurs, are marked and filled at the end. The experiments include three sets of indoor scenes and one set of outdoor scene. The lighting condition and the structure of each scene are different and so is the nature of their texture. Various camera configurations are set up with different number of cameras, baselines, and viewpoints. Selected estimated voxels are compared with their true geometry. Results of

  8. Unmanned Aerial Vehicle (UAV) Dynamic-Tracking Directional Wireless Antennas for Low Powered Applications that Require Reliable Extended Range Operations in Time Critical Scenarios

    SciTech Connect

    Scott G. Bauer; Matthew O. Anderson; James R. Hanneman

    2005-10-01

    The proven value of DOD Unmanned Aerial Vehicles (UAVs) will ultimately transition to National and Homeland Security missions that require real-time aerial surveillance, situation awareness, force protection, and sensor placement. Public services first responders who routinely risk personal safety to assess and report a situation for emergency actions will likely be the first to benefit from these new unmanned technologies. ‘Packable’ or ‘Portable’ small class UAVs will be particularly useful to the first responder. They require the least amount of training, no fixed infrastructure, and are capable of being launched and recovered from the point of emergency. All UAVs require wireless communication technologies for real- time applications. Typically on a small UAV, a low bandwidth telemetry link is required for command and control (C2), and systems health monitoring. If the UAV is equipped with a real-time Electro-Optical or Infrared (EO/Ir) video camera payload, a dedicated high bandwidth analog/digital link is usually required for reliable high-resolution imagery. In most cases, both the wireless telemetry and real-time video links will be integrated into the UAV with unity gain omni-directional antennas. With limited on-board power and payload capacity, a small UAV will be limited with the amount of radio-frequency (RF) energy it transmits to the users. Therefore, ‘packable’ and ‘portable’ UAVs will have limited useful operational ranges for first responders. This paper will discuss the limitations of small UAV wireless communications. The discussion will present an approach of utilizing a dynamic ground based real-time tracking high gain directional antenna to provide extend range stand-off operation, potential RF channel reuse, and assured telemetry and data communications from low-powered UAV deployed wireless assets.

  9. An approach to improve direct runoff estimates and reduce uncertainty in the calculated groundwater component in water balances of large lakes

    NASA Astrophysics Data System (ADS)

    Wiebe, Andrew J.; Conant, Brewster; Rudolph, David L.; Korkka-Niemi, Kirsti

    2015-12-01

    Groundwater is important in the overall water budget of a lake because it affects the quantity and quality of surface water and the ecological health of the lake. The water balance equation is frequently used to estimate the net groundwater flow for small lakes but is seldom used to determine net groundwater flow components for large lakes because: (1) errors accumulate in the calculated groundwater term, and (2) there is an inability to accurately quantify the direct runoff component. In this water balance study of Lake Pyhäjärvi (155 km2) in Finland, it was hypothesized a hydrograph separation model could be used to estimate direct runoff to the lake and, when combined with a rigorous uncertainty analyses, would provide reliable net groundwater flow estimates. The PART hydrograph separation model was used to estimate annual per unit area direct runoff values for the watershed of the inflowing Yläneenjoki River (a subwatershed of the lake) which were then applied to other physically similar subwatersheds of the lake to estimate total direct runoff to the lake. The hydrograph separation method provided superior results and had lower uncertainty than the common approach of using a runoff coefficient based method. The average net groundwater flow into the lake was calculated to be +43 mm per year (+3.0% of average total inflow) for the 38 water years 1971-2008. It varied from -197 mm to 284 mm over that time, and had a magnitude greater than the uncertainty for 17 of the 38 years. The average indirect groundwater contribution to the lake (i.e., the groundwater part of the inflowing rivers) was 454 mm per year (+32% of average total inflow) and demonstrates the overall importance of groundwater. The techniques in this study are applicable to other large lakes and may allow small net groundwater flows to be reliably quantified in settings that might otherwise be unquantifiable or completely lost in large uncertainties.

  10. Effectiveness of the Gaze Direction Recognition Task for Chronic Neck Pain and Cervical Range of Motion: A Randomized Controlled Pilot Study

    PubMed Central

    Nobusako, Satoshi; Matsuo, Atsushi; Morioka, Shu

    2012-01-01

    We developed a mental task with gaze direction recognition (GDR) by which subjects observed neck rotation of another individual from behind and attempted to recognize the direction of gaze. A randomized controlled trial was performed in test (n = 9) and control (n = 8) groups of subjects with chronic neck pain undergoing physical therapy either with or without the GDR task carried out over 12 sessions during a three-week period. Primary outcome measures were defined as the active range of motion and pain on rotation of the neck. Secondary outcome measures were reaction time (RT) and response accuracy in the GDR task group. ANOVA indicated a main effect for task session and group, and interaction of session. Post hoc testing showed that the GDR task group exhibited a significant simple main effect upon session, and significant sequential improvement of neck motion and relief of neck pain. Rapid effectiveness was significant in both groups. The GDR task group had a significant session-to-session reduction of RTs in correct responses. In conclusion, the GDR task we developed provides a promising rehabilitation measure for chronic neck pain. PMID:22645685

  11. Towards direct realisation of the SI unit of sound pressure in the audible hearing range based on optical free-field acoustic particle measurements

    NASA Astrophysics Data System (ADS)

    Koukoulas, Triantafillos; Piper, Ben

    2015-04-01

    Since the introduction of the International System of Units (the SI system) in 1960, weights, measures, standardised approaches, procedures, and protocols have been introduced, adapted, and extensively used. A major international effort and activity concentrate on the definition and traceability of the seven base SI units in terms of fundamental constants, and consequently those units that are derived from the base units. In airborne acoustical metrology and for the audible range of frequencies up to 20 kHz, the SI unit of sound pressure, the pascal, is realised indirectly and without any knowledge or measurement of the sound field. Though the principle of reciprocity was originally formulated by Lord Rayleigh nearly two centuries ago, it was devised in the 1940s and eventually became a calibration standard in the 1960s; however, it can only accommodate a limited number of acoustic sensors of specific types and dimensions. International standards determine the device sensitivity either through coupler or through free-field reciprocity but rely on the continuous availability of specific acoustical artefacts. Here, we show an optical method based on gated photon correlation spectroscopy that can measure sound pressures directly and absolutely in fully anechoic conditions, remotely, and without disturbing the propagating sound field. It neither relies on the availability or performance of any measurement artefact nor makes any assumptions of the device geometry and sound field characteristics. Most importantly, the required units of sound pressure and microphone sensitivity may now be experimentally realised, thus providing direct traceability to SI base units.

  12. Towards direct realisation of the SI unit of sound pressure in the audible hearing range based on optical free-field acoustic particle measurements

    SciTech Connect

    Koukoulas, Triantafillos Piper, Ben

    2015-04-20

    Since the introduction of the International System of Units (the SI system) in 1960, weights, measures, standardised approaches, procedures, and protocols have been introduced, adapted, and extensively used. A major international effort and activity concentrate on the definition and traceability of the seven base SI units in terms of fundamental constants, and consequently those units that are derived from the base units. In airborne acoustical metrology and for the audible range of frequencies up to 20 kHz, the SI unit of sound pressure, the pascal, is realised indirectly and without any knowledge or measurement of the sound field. Though the principle of reciprocity was originally formulated by Lord Rayleigh nearly two centuries ago, it was devised in the 1940s and eventually became a calibration standard in the 1960s; however, it can only accommodate a limited number of acoustic sensors of specific types and dimensions. International standards determine the device sensitivity either through coupler or through free-field reciprocity but rely on the continuous availability of specific acoustical artefacts. Here, we show an optical method based on gated photon correlation spectroscopy that can measure sound pressures directly and absolutely in fully anechoic conditions, remotely, and without disturbing the propagating sound field. It neither relies on the availability or performance of any measurement artefact nor makes any assumptions of the device geometry and sound field characteristics. Most importantly, the required units of sound pressure and microphone sensitivity may now be experimentally realised, thus providing direct traceability to SI base units.

  13. Genetic susceptibility to chronic wasting disease in free-ranging white-tailed deer: complement component C1q and Prnp polymorphisms

    USGS Publications Warehouse

    Blanchong, Julie A.; Heisey, Dennis M.; Scribner, Kim T.; Libants, Scot V.; Johnson, Chad; Aiken, Judd M.; Langenberg, Julia A.; Samuel, Michael D.

    2009-01-01

    The genetic basis of susceptibility to chronic wasting disease (CWD) in free-ranging cervids is of great interest. Association studies of disease susceptibility in free-ranging populations, however, face considerable challenges including: the need for large sample sizes when disease is rare, animals of unknown pedigree create a risk of spurious results due to population admixture, and the inability to control disease exposure or dose. We used an innovative matched case–control design and conditional logistic regression to evaluate associations between polymorphisms of complement C1q and prion protein (Prnp) genes and CWD infection in white-tailed deer from the CWD endemic area in south-central Wisconsin. To reduce problems due to admixture or disease-risk confounding, we used neutral genetic (microsatellite) data to identify closely related CWD-positive (n = 68) and CWD-negative (n = 91) female deer to serve as matched cases and controls. Cases and controls were also matched on factors (sex, location, age) previously demonstrated to affect CWD infection risk. For Prnp, deer with at least one Serine (S) at amino acid 96 were significantly less likely to be CWD-positive relative to deer homozygous for Glycine (G). This is the first characterization of genes associated with the complement system in white-tailed deer. No tests for association between any C1q polymorphism and CWD infection were significant at p < 0.05. After controlling for Prnp, we found weak support for an elevated risk of CWD infection in deer with at least one Glycine (G) at amino acid 56 of the C1qC gene. While we documented numerous amino acid polymorphisms in C1q genes none appear to be strongly associated with CWD susceptibility.

  14. A stock market forecasting model combining two-directional two-dimensional principal component analysis and radial basis function neural network.

    PubMed

    Guo, Zhiqiang; Wang, Huaiqing; Yang, Jie; Miller, David J

    2015-01-01

    In this paper, we propose and implement a hybrid model combining two-directional two-dimensional principal component analysis ((2D)2PCA) and a Radial Basis Function Neural Network (RBFNN) to forecast stock market behavior. First, 36 stock market technical variables are selected as the input features, and a sliding window is used to obtain the input data of the model. Next, (2D)2PCA is utilized to reduce the dimension of the data and extract its intrinsic features. Finally, an RBFNN accepts the data processed by (2D)2PCA to forecast the next day's stock price or movement. The proposed model is used on the Shanghai stock market index, and the experiments show that the model achieves a good level of fitness. The proposed model is then compared with one that uses the traditional dimension reduction method principal component analysis (PCA) and independent component analysis (ICA). The empirical results show that the proposed model outperforms the PCA-based model, as well as alternative models based on ICA and on the multilayer perceptron. PMID:25849483

  15. A Stock Market Forecasting Model Combining Two-Directional Two-Dimensional Principal Component Analysis and Radial Basis Function Neural Network

    PubMed Central

    Guo, Zhiqiang; Wang, Huaiqing; Yang, Jie; Miller, David J.

    2015-01-01

    In this paper, we propose and implement a hybrid model combining two-directional two-dimensional principal component analysis ((2D)2PCA) and a Radial Basis Function Neural Network (RBFNN) to forecast stock market behavior. First, 36 stock market technical variables are selected as the input features, and a sliding window is used to obtain the input data of the model. Next, (2D)2PCA is utilized to reduce the dimension of the data and extract its intrinsic features. Finally, an RBFNN accepts the data processed by (2D)2PCA to forecast the next day's stock price or movement. The proposed model is used on the Shanghai stock market index, and the experiments show that the model achieves a good level of fitness. The proposed model is then compared with one that uses the traditional dimension reduction method principal component analysis (PCA) and independent component analysis (ICA). The empirical results show that the proposed model outperforms the PCA-based model, as well as alternative models based on ICA and on the multilayer perceptron. PMID:25849483

  16. Rotary balance data for a typical single-engine general aviation design for an angle-of-attack range of 8 deg to 90 deg. 1: Influence of airplane components for model D. [Langley spin tunnel tests

    NASA Technical Reports Server (NTRS)

    Ralston, J.

    1983-01-01

    The influence of airplane components, as well as wing location and tail length, on the rotational flow aerodynamics is discussed for a 1/6 scale general aviation airplane model. The airplane was tested in a built-up fashion (i.e., body, body-wing, body-wing-vertical, etc.) in the presence of two wing locations and two body lengths. Data were measured, using a rotary balance, over an angle-of-attack range of 8 deg to 90 deg, and for clockwise and counter-clockwise rotations covering an omega b/2V range of 0 to 0.9.

  17. Assessing fluctuating odontometric asymmetry among fossil hominin taxa through alternative measures of central tendency: effect of outliers and directional components on reported results.

    PubMed

    Kegley, A D T; Hemingway, J

    2007-01-01

    Preliminary inquires into the distribution and expression of fluctuating odontometric asymmetry (FOA), among selected fossil hominins, have revealed results that may be serviceable within studies that assess, among others, palaeobiological, evolutionary processes and events. Though several intricate statistical applications have aided in the advancement of FOA to the hominin fossil record, little is known regarding the influence of outliers and directional components on reported results. Moreover, most methods employed to test homogeneity among FOA datasets are sensitive to the assumption that underlying samples reflect Gaussian distributions. Because this assumption is often violated, alternative formulations of Levene's test statistic, which have been shown to be robust under non-normality, have been suggested. Unfortunately, previous FOA studies have failed to address their potential. Given this, we considered two areas that may influence interpretations of FOA among fossil hominin studies. Firstly, we assessed distributions of signed data (d(u)) among samples of Australopithecus africanus, Paranthropus robustus and Homo habilis for outliers and directional asymmetry to evaluate their influence on reported heterogeneity. Secondly, in an attempt to decrease the probability of falsely rejecting H(0) due to non-normality, we considered alternative estimates of central tendency for comparisons of FOA. Our study confirms the need for intrinsic scrutiny of data, as the removal of one extreme value within the buccolingual H. habilis sample produced statistically significant outcomes at the sample level, while directional asymmetry was exposed within an expanded buccolingual P. robustus sample. However, though servicing alternative measures of central tendency remains informative, except for the buccolingual P. robustus sample before the correction of directional asymmetry, replacement of the mean was not required herein. Consistent with previous investigations

  18. A Triple-Band WCDMA Direct Conversion Receiver IC with Reduced Number of Off-Chip Components and Digital Baseband Control Signals

    NASA Astrophysics Data System (ADS)

    Watanabe, Osamu; Ito, Rui; Mitomo, Toshiya; Saigusa, Shigehito; Arai, Tadashi; Toyoda, Takehiko

    This paper presents a triple-band WCDMA direct conversion receiver (DCR) IC that needs a small number of off-chip components and control signals from digital baseband (DBB) IC. The DCR IC consists of 3 quadrature demodulators (QDEMs) with on-chip impedance matching circuit and an analog baseband block (ABB) that contains a low-pass filter (LPF) with fc automatic tuning circuit using no off-chip components and a linear-in-dB variable-gain amplifier (VGA) with on-chip analog high-pass filter (HPF). In order to make use of DBB control-free DC offset canceler, the DCR is designed to avoid large gain change under large interference that causes long transient response. In order to realize that characteristic without increasing quiescent current, the QDEM is used that employs class AB input stage and low-noise common mode feedback (CMFB) output stage. The DCR IC was fabricated in a SiGe BiCMOS process and occupies about 2.9mm×3.0mm. The DCR needs SAW filters only for off-chip components and a gain control signal from DBB IC for AGC loop. The IIP3 of over -4.4dBm for small signal input level and that of over +1.9dBm for large signal input level are achieved. The gain compression of the desired signal is less than 0.3dB for ACS Case-II condition.

  19. Rapid screening for the adulterants of Berberis aristata using direct analysis in real-time mass spectrometry and principal component analysis for discrimination.

    PubMed

    Bajpai, Vikas; Singh, Awantika; Arya, Kamal Ram; Srivastava, Mukesh; Kumar, Brijesh

    2015-01-01

    Adulteration or substitution of commercial Berberis aristata and its herbal products with inferior-quality substituents is very common. Metabolic profiling of B. aristata, along with its common adulterants/contaminants/substituents such as B. asiatica, Mahonia borealis and Coscinium fenestratum, was rapidly carried out using direct analysis in real-time mass spectrometry (DART MS) to generate the chemical fingerprints for the differentiation of these species. Phytochemical analysis showed the presence of mainly alkaloids. The identified alkaloids were berberrubine, berberine, jatrorrhizine, ketoberberine, palmatine, dihydropalmatine or 7,8-dihydro-8-hydroxyberberine, berbamine and pakistanamine. Berberine, which was mainly reported from the root and stem bark of B. aristata, was also identified in the leaf along with chlorogenic acid. The DART MS data have been subjected to principal component analysis (PCA). The resulting score plots showed clustering and clear differentiation of the species and plant parts. It is thus apparent that the technique of DART MS followed by PCA is a quick and reliable method for the direct profiling of B. aristata and its adulterant plants and plant parts. The study reports the rapid analytical method to identify the possibility of illegal adulteration/contamination/substitution in potential plant materials and herbal extracts. PMID:25739096

  20. Using SpaceClaim/TD Direct for Modeling Components with Complex Geometries for the Thermal Desktop-Based Advanced Stirling Radioisotope Generator Model

    NASA Technical Reports Server (NTRS)

    Fabanich, William

    2014-01-01

    SpaceClaim/TD Direct has been used extensively in the development of the Advanced Stirling Radioisotope Generator (ASRG) thermal model. This paper outlines the workflow for that aspect of the task and includes proposed best practices and lessons learned. The ASRG thermal model was developed to predict component temperatures and power output and to provide insight into the prime contractors thermal modeling efforts. The insulation blocks, heat collectors, and cold side adapter flanges (CSAFs) were modeled with this approach. The model was constructed using mostly TD finite difference (FD) surfaces solids. However, some complex geometry could not be reproduced with TD primitives while maintaining the desired degree of geometric fidelity. Using SpaceClaim permitted the import of original CAD files and enabled the defeaturing repair of those geometries. TD Direct (a SpaceClaim add-on from CRTech) adds features that allowed the mark-up of that geometry. These so-called mark-ups control how finite element (FE) meshes were generated and allowed the tagging of features (e.g. edges, solids, surfaces). These tags represent parameters that include: submodels, material properties, material orienters, optical properties, and radiation analysis groups. TD aliases were used for most tags to allow analysis to be performed with a variety of parameter values. Domain-tags were also attached to individual and groups of surfaces and solids to allow them to be used later within TD to populate objects like, for example, heaters and contactors. These tools allow the user to make changes to the geometry in SpaceClaim and then easily synchronize the mesh in TD without having to redefine these objects each time as one would if using TD Mesher.The use of SpaceClaim/TD Direct has helped simplify the process for importing existing geometries and in the creation of high fidelity FE meshes to represent complex parts. It has also saved time and effort in the subsequent analysis.

  1. Using SpaceClaimTD Direct for Modeling Components with Complex Geometries for the Thermal Desktop-Based Advanced Stirling Radioisotope Generator Model

    NASA Technical Reports Server (NTRS)

    Fabanich, William A., Jr.

    2014-01-01

    SpaceClaim/TD Direct has been used extensively in the development of the Advanced Stirling Radioisotope Generator (ASRG) thermal model. This paper outlines the workflow for that aspect of the task and includes proposed best practices and lessons learned. The ASRG thermal model was developed to predict component temperatures and power output and to provide insight into the prime contractor's thermal modeling efforts. The insulation blocks, heat collectors, and cold side adapter flanges (CSAFs) were modeled with this approach. The model was constructed using mostly TD finite difference (FD) surfaces/solids. However, some complex geometry could not be reproduced with TD primitives while maintaining the desired degree of geometric fidelity. Using SpaceClaim permitted the import of original CAD files and enabled the defeaturing/repair of those geometries. TD Direct (a SpaceClaim add-on from CRTech) adds features that allowed the "mark-up" of that geometry. These so-called "mark-ups" control how finite element (FE) meshes are to be generated through the "tagging" of features (e.g. edges, solids, surfaces). These tags represent parameters that include: submodels, material properties, material orienters, optical properties, and radiation analysis groups. TD aliases were used for most tags to allow analysis to be performed with a variety of parameter values. "Domain-tags" were also attached to individual and groups of surfaces and solids to allow them to be used later within TD to populate objects like, for example, heaters and contactors. These tools allow the user to make changes to the geometry in SpaceClaim and then easily synchronize the mesh in TD without having to redefine the objects each time as one would if using TDMesher. The use of SpaceClaim/TD Direct helps simplify the process for importing existing geometries and in the creation of high fidelity FE meshes to represent complex parts. It also saves time and effort in the subsequent analysis.

  2. Communication between thiamin cofactors in the Escherichia coli pyruvate dehydrogenase complex E1 component active centers: evidence for a "direct pathway" between the 4'-aminopyrimidine N1' atoms.

    PubMed

    Nemeria, Natalia S; Arjunan, Palaniappa; Chandrasekhar, Krishnamoorthy; Mossad, Madouna; Tittmann, Kai; Furey, William; Jordan, Frank

    2010-04-01

    Kinetic, spectroscopic, and structural analysis tested the hypothesis that a chain of residues connecting the 4'-aminopyrimidine N1' atoms of thiamin diphosphates (ThDPs) in the two active centers of the Escherichia coli pyruvate dehydrogenase complex E1 component provides a signal transduction pathway. Substitution of the three acidic residues (Glu(571), Glu(235), and Glu(237)) and Arg(606) resulted in impaired binding of the second ThDP, once the first active center was filled, suggesting a pathway for communication between the two ThDPs. 1) Steady-state kinetic and fluorescence quenching studies revealed that upon E571A, E235A, E237A, and R606A substitutions, ThDP binding in the second active center was affected. 2) Analysis of the kinetics of thiazolium C2 hydrogen/deuterium exchange of enzyme-bound ThDP suggests half-of-the-sites reactivity for the E1 component, with fast (activated site) and slow exchanging sites (dormant site). The E235A and E571A variants gave no evidence for the slow exchanging site, indicating that only one of two active sites is filled with ThDP. 3) Titration of the E235A and E237A variants with methyl acetylphosphonate monitored by circular dichroism suggested that only half of the active sites were filled with a covalent predecarboxylation intermediate analog. 4) Crystal structures of E235A and E571A in complex with ThDP revealed the structural basis for the spectroscopic and kinetic observations and showed that either substitution affects cofactor binding, despite the fact that Glu(235) makes no direct contact with the cofactor. The role of the conserved Glu(571) residue in both catalysis and cofactor orientation is revealed by the combined results for the first time. PMID:20106967

  3. Subcellular localisation of the p40phox component of NADPH oxidase involves direct interactions between the Phox homology domain and F-actin

    PubMed Central

    Shao, Dongmin; Segal, Anthony W.; Dekker, Lodewijk V.

    2010-01-01

    Cytosolic components of the NADPH oxidase interact with the actin cytoskeleton. These interactions are thought to be important for the activation of this enzyme system but they are poorly characterised at the molecular level. Here we have explored the interaction between the actin cytoskeleton and p40phox, one of the cytosolic components of NADPH oxidase. Full length p40phox expressed in COS cells co-localised with F-actin in a peripheral lamellar compartment. The co-localisation was lost after deletion of the Phox homology (PX) domain and the PX domain in isolation (p40PX) showed the same F-actin co-localisation as the full length protein. PX domains are known lipid-binding modules however, a mutant p40PX which did not bind lipids still co-localised with F-actin suggesting that lipid-independent interactions underlie the localisation. Affinity chromatography identified actin as a binding partner for p40PX in neutrophil extracts. Pure actin interacted with both p40phox and with p40PX suggesting it is a direct interaction. Disruption of the actin cytoskeleton with cytochalasin D resulted in actin rearrangement and concomitantly the localisation of full length p40phox proteins and that of p40PX changed. Thus p40PX is a dual F-actin/lipid-binding module and F-actin interactions with the PX domain dictate at least in part the intracellular localisation of the cytosolic p40phox subunit of the NADPH oxidase. PMID:20637895

  4. The Essential yhcSR Two-Component Signal Transduction System Directly Regulates the lac and opuCABCD Operons of Staphylococcus aureus

    PubMed Central

    Yan, Meiying; Hall, Jeffrey W.; Yang, Junshu; Ji, Yinduo

    2012-01-01

    Our previous studies suggested that the essential two-component signal transduction system, YhcSR, regulates the opuCABCD operon at the transcriptional level, and the Pspac-driven opuCABCD partially complements the lethal effects of yhcS antisense RNA expression in Staphylococcus aureus. However, the reason why yhcSR regulon is required for growth is still unclear. In this report, we present that the lac and opuC operons are directly transcriptionally regulated by YhcSR. Using real-time RT-PCR we showed that the down-regulation of yhcSR expression affected the transcription of lacA encoding galactose-6-phosphotase isomerase subunit LacA, and opuCA encoding a subunit of a glycine betaine/carnitine/choline ABC transporter. Promoter-lux reporter fusion studies further confirmed the transcriptional regulation of lac by YhcSR. Gel shift assays revealed that YhcR binds to the promoter regions of the lac and opuC operons. Moreover, the Pspac-driven lacABC expression in trans was able to partially complement the lethal effect of induced yhcS antisense RNA. Likewise, the Pspac-driven opuCABCD expression in trans complemented the growth defect of S. aureus in a high osmotic strength medium during the depletion of YhcSR. Taken together, the above data indicate that the yhcSR system directly regulates the expression of lac and opuC operons, which, in turn, may be partially associated with the essentiality of yhcSR in S. aureus. These results provide a new insight into the biological functions of the yhcSR, a global regulator. PMID:23226327

  5. Measurement of the x-ray mass attenuation coefficient and determination of the imaginary component of the atomic form-factor of tin over the energy range of 29 keV-60 keV.

    SciTech Connect

    de Jonge, M. D.; Tran, C. Q.; Chantler, C. T.; Barnea, Z.; Dhal, B. P.; Paterson, D.; Kanter, E. P.; Southworth, S. H.; Young, L.; Beno, M. A.; Linton, J. A.; Jennings, G.; Univ. of Melbourne; Australian Synchrotron Project

    2007-01-01

    We use the x-ray extended-range technique (XERT) [C. T. Chantler et al., Phys. Rev. A 64, 062506 (2001)] to measure the mass attenuation coefficients of tin in the x-ray energy range of 29-60 keV to 0.04-3 % accuracy, and typically in the range 0.1-0.2 %. Measurements made over an extended range of the measurement parameter space are critically examined to identify, quantify, and correct a number of potential experimental systematic errors. These results represent the most extensive experimental data set for tin and include absolute mass attenuation coefficients in the regions of x-ray absorption fine structure, extended x-ray absorption fine structure, and x-ray absorption near-edge structure. The imaginary component of the atomic form factor f{sub 2} is derived from the photoelectric absorption after subtracting calculated Rayleigh and Compton scattering cross sections from the total attenuation. Comparison of the result with tabulations of calculated photoelectric absorption coefficients indicates that differences of 1-2 % persist between calculated and observed values.

  6. The ETS domain transcription factor ELK1 directs a critical component of growth signaling by the androgen receptor in prostate cancer cells.

    PubMed

    Patki, Mugdha; Chari, Venkatesh; Sivakumaran, Suneethi; Gonit, Mesfin; Trumbly, Robert; Ratnam, Manohar

    2013-04-19

    The androgen receptor (AR) is essential for diverse aspects of prostate development and function. Molecular mechanisms by which prostate cancer (PC) cells redirect AR signaling to genes that primarily support growth are unclear. A systematic search for critical AR-tethering proteins led to ELK1, an ETS transcription factor of the ternary complex factor subfamily. Although genetically redundant, ELK1 was obligatory for AR-dependent growth and clonogenic survival in both hormone-dependent PC and castration-recurrent PC cells but not for AR-negative cell growth. AR required ELK1 to up-regulate a major subset of its target genes that was strongly and primarily enriched for cell growth functions. AR functioned as a coactivator of ELK1 by association through its A/B domain, bypassing the classical mechanism of ELK1 activation by phosphorylation and without inducing ternary complex target genes. The ELK1-AR synergy per se was ligand-independent, although it required ligand for nuclear localization of AR as targeting the AR A/B domain to the nucleus recapitulated the action of hormone; accordingly, Casodex was a poor antagonist of the synergy. ELK3, the closest substitute for ELK1 in structure/function and genome recognition, did not interact with AR. ELK1 thus directs selective and sustained gene induction that is a substantial and critical component of growth signaling by AR in PC cells. The ELK1-AR interaction offers a functionally tumor-selective drug target. PMID:23426362

  7. Range and range rate system

    NASA Technical Reports Server (NTRS)

    Graham, Olin L. (Inventor); Russell, Jim K. (Inventor); Epperly, Walter L. (Inventor)

    1988-01-01

    A video controlled solid state range finding system which requires no radar, high power laser, or sophisticated laser target is disclosed. The effective range of the system is from 1 to about 200 ft. The system includes an opto-electric camera such as a lens CCD array device. A helium neon laser produces a source beam of coherent light which is applied to a beam splitter. The beam splitter applies a reference beam to the camera and produces an outgoing beam applied to a first angularly variable reflector which directs the outgoing beam to the distant object. An incoming beam is reflected from the object to a second angularly variable reflector which reflects the incoming beam to the opto-electric camera via the beam splitter. The first reflector and the second reflector are configured so that the distance travelled by the outgoing beam from the beam splitter and the first reflector is the same as the distance travelled by the incoming beam from the second reflector to the beam splitter. The reference beam produces a reference signal in the geometric center of the camera. The incoming beam produces an object signal at the camera.

  8. Measurement of the x-ray mass attenuation coefficient and determination of the imaginary component of the atomic form factor of molybdenum over the 13.5-41.5-keV energy range

    NASA Astrophysics Data System (ADS)

    de Jonge, Martin D.; Tran, Chanh Q.; Chantler, Christopher T.; Barnea, Zwi; Dhal, Bipin B.; Cookson, David J.; Lee, Wah-Keat; Mashayekhi, Ali

    2005-03-01

    We use the x-ray extended-range technique (XERT) [Chantler , Phys. Rev. A 64, 062506 (2001)] to measure the mass attenuation coefficients of molybdenum in the x-ray energy range of 13.5-41.5keV to 0.02-0.15 % accuracy. Measurements made over an extended range of the measurement parameter space are critically examined to identify, quantify, and correct where necessary a number of experimental systematic errors. These results represent the most extensive experimental data set for molybdenum and include absolute mass attenuation coefficients in the regions of the x-ray absorption fine structure (XAFS) and x-ray-absorption near-edge structure (XANES). The imaginary component of the atomic form-factor f2 is derived from the photoelectric absorption after subtracting calculated Rayleigh and Compton scattering cross sections from the total attenuation. Comparison of the result with tabulations of calculated photoelectric absorption coefficients indicates that differences of 1-15 % persist between the calculated and observed values.

  9. Low-background balloon-borne direct search for ionizing massive particles as a component of the dark galactic halo matter

    NASA Astrophysics Data System (ADS)

    McGuire, Patrick Charles

    A dark matter (DM) search experiment was flown on the IMAX balloon payload, which tested the hypothesis that a minor component of the dark matter in the Galactic halo is composed of ionizing (dE/dx greater than 1 MeV/g/cm2 or sigma greater than 2 x 10-20 sq cm supermassive particles (mx is an element of (104, 1012)GeV/c2 that cannot penetrate the atmosphere due to their low velocities (beta belongs to (0.0003, 0.00025)). The DM search experiment consisted of a delayed coincidence between four approximately 2400 cm2 plastic scintillation detectors, with a total acceptance of approximately 100 cm2 sr. In order to search for ultra-slow particles which do not slow down in the IMAX telescope, the experiment contained TDCs which measured the time-delays Ti,i+1is an element of (0.3, 14.0)microseconds between hits in a successive counters to approximately 1 percent precision. Using the first 5 hours of data at float altitude (5 g/sq cm residual atmosphere), we observed approximately 5 candidate non-slowing dark matter events, consistent with the background from accidental coincidences of 4 events. This implies that the DM flux is less than 6.5 x 10-6 cm-2s-1sr-1 (95 percent C.L.). Similar results were also obtained for particles which slow down in the counter telescope. This experiment effectively closes much of a previously unconstrained 'window' in the mass/cross-section joint parameter space for massive particles as the dominant halo DM, and implies that for certain regions of this parameter space massive particles cannot be more than one part in 105 by mass of all the DM. These results can also directly constrain 'light' magnetic monopoles and neutra CHAMPs in a previously unconstrained mass region mx belongs to (106, 109) GeV.

  10. Development of an in-situ multi-component reinforced Al-based metal matrix composite by direct metal laser sintering technique — Optimization of process parameters

    SciTech Connect

    Ghosh, Subrata Kumar; Bandyopadhyay, Kaushik; Saha, Partha

    2014-07-01

    In the present investigation, an in-situ multi-component reinforced aluminum based metal matrix composite was fabricated by the combination of self-propagating high-temperature synthesis and direct metal laser sintering process. The different mixtures of Al, TiO{sub 2} and B{sub 4}C powders were used to initiate and maintain the self-propagating high-temperature synthesis by laser during the sintering process. It was found from the X-ray diffraction analysis and scanning electron microscopy that the reinforcements like Al{sub 2}O{sub 3}, TiC, and TiB{sub 2} were formed in the composite. The scanning electron microscopy revealed the distribution of the reinforcement phases in the composite and phase identities. The variable parameters such as powder layer thickness, laser power, scanning speed, hatching distance and composition of the powder mixture were optimized for higher density, lower porosity and higher microhardness using Taguchi method. Experimental investigation shows that the density of the specimen mainly depends upon the hatching distance, composition and layer thickness. On the other hand, hatching distance, layer thickness and laser power are the significant parameters which influence the porosity. The composition, laser power and layer thickness are the key influencing parameters for microhardness. - Highlights: • The reinforcements such as Al{sub 2}O{sub 3}, TiC, and TiB{sub 2} were produced in Al-MMC through SHS. • The density is mainly influenced by the material composition and hatching distance. • Hatching distance is the major influencing parameter on porosity. • The material composition is the significant parameter to enhance the microhardness. • The SEM micrographs reveal the distribution of TiC, TiB{sub 2} and Al{sub 2}O{sub 3} in the composite.

  11. Broad-Range Direct Detection and Identification of Fungi by Use of the PLEX-ID PCR-Electrospray Ionization Mass Spectrometry (ESI-MS) System

    PubMed Central

    Simner, Patricia J.; Uhl, James R.; Hall, Leslie; Weber, Michelle M.; Walchak, Robert C.; Buckwalter, Seanne

    2013-01-01

    The PLEX-ID system is a novel technology that couples PCR amplification and electrospray ionization-mass spectrometry to identify pathogens directly in clinical specimens. The analytical performance of the PLEX-ID Broad Fungal assay was compared with that of traditional culture identification by using 91 characterized fungal culture isolates (64 manufacturer-claimed and 27 nonclaimed organisms) and directly by using 395 respiratory specimens. Discordant results were resolved by D2 large-subunit ribosomal DNA fungal sequencing. Environmental studies were performed to monitor for potential contamination. The PLEX-ID Broad Fungal assay correctly identified 95.6% (87/91) and 81.3% (74/91) of the culture isolates to the genus and species levels, respectively. Of the manufacturer-claimed organisms, 100% (64/64) and 92.2% (59/64) were correctly identified to the genus and species levels, respectively. Direct analysis of respiratory specimens resulted in 67.6% (267/395) and 66.6% (263/395) agreement with culture results to the genus and species levels, respectively, with 16.2% (64/395) of the results discordant with culture and 16.2% (64/395) not detected by the system. The majority (>95%) of the isolates not detected directly by the PLEX-ID system ultimately grew in low quantities in culture (≤20 colonies). In 20.3% (35/172) of the respiratory specimens where no growth was observed in culture, the PLEX-ID system identified a fungus, suggesting a potential increase in sensitivity over culture in some instances. The PLEX-ID system provides a rapid method for the detection of a broad array of fungi directly in respiratory specimens and has the potential of impacting turnaround times and patient care by reducing the need to wait for the growth of an organism in culture. PMID:23515540

  12. Direct Observation of Short-Range Structural Coherence During a Charge Transfer Induced Spin Transition in a CoFe Prussian Blue Analogue by Transmission Electron Microscopy.

    PubMed

    Itoi, Miho; Jike, Toyoharu; Nishio-Hamane, Daisuke; Udagawa, Seiichi; Tsuda, Tetsuya; Kuwabata, Susumu; Boukheddaden, Kamel; Andrus, Matthew J; Talham, Daniel R

    2015-11-25

    The local structure within the Co-Fe atomic array of the photoswitchable coordination polymer magnet, K0.3Co[Fe(CN)6]0.77·nH2O, is directly observed during charge transfer induced spin transition (CTIST), a solid-solid phase change, using high-resolution transmission electron microscopy (HRTEM). Along with the low-spin (LS) or thermally quenched high-spin (HS) states normally observed in CTIST solids at low temperature, slow cooling of K0.3Co[Fe(CN)6]0.77·nH2O results in an intermediate phase containing both HS and LS domains with short coherence length. By mapping individual metal-metal distances, the nanometer-scale HS domains are directly visualized within the LS array. Temperature-dependent analyses allow monitoring of HS domain coarsening along the warming branch of the CTIST, providing direct visualization of the elastic process and insight into the mechanism of phase propagation. Normally sensitive to electron beam damage, the low-temperature TEM measurements of the porous coordination polymer are enabled by using appropriate ionic liquids instead of usual conductive thin-film coatings, an approach that should find general utility in related classes of materials. PMID:26510096

  13. Energy Dependence of Directed Flow over a Wide Range of Pseudorapidity in Au+Au Collisions at the BNL Relativistic Heavy Ion Collider

    NASA Astrophysics Data System (ADS)

    Back, B. B.; Baker, M. D.; Ballintijn, M.; Barton, D. S.; Betts, R. R.; Bickley, A. A.; Bindel, R.; Budzanowski, A.; Busza, W.; Carroll, A.; Chai, Z.; Decowski, M. P.; García, E.; Gburek, T.; George, N.; Gulbrandsen, K.; Gushue, S.; Halliwell, C.; Hamblen, J.; Hauer, M.; Heintzelman, G. A.; Henderson, C.; Hofman, D. J.; Hollis, R. S.; Hołyński, R.; Holzman, B.; Iordanova, A.; Johnson, E.; Kane, J. L.; Katzy, J.; Khan, N.; Kucewicz, W.; Kulinich, P.; Kuo, C. M.; Lin, W. T.; Manly, S.; McLeod, D.; Mignerey, A. C.; Nouicer, R.; Olszewski, A.; Pak, R.; Park, I. C.; Pernegger, H.; Reed, C.; Remsberg, L. P.; Reuter, M.; Roland, C.; Roland, G.; Rosenberg, L.; Sagerer, J.; Sarin, P.; Sawicki, P.; Seals, H.; Sedykh, I.; Skulski, W.; Smith, C. E.; Stankiewicz, M. A.; Steinberg, P.; Stephans, G. S. F.; Sukhanov, A.; Tang, J.-L.; Tonjes, M. B.; Trzupek, A.; Vale, C.; van Nieuwenhuizen, G. J.; Vaurynovich, S. S.; Verdier, R.; Veres, G. I.; Wenger, E.; Wolfs, F. L. H.; Wosiek, B.; Woźniak, K.; Wuosmaa, A. H.; Wysłouch, B.

    2006-07-01

    We report on measurements of directed flow as a function of pseudorapidity in Au+Au collisions at energies of sNN=19.6, 62.4, 130 and 200 GeV as measured by the PHOBOS detector at the BNL Relativistic Heavy Ion Collider. These results are particularly valuable because of the extensive, continuous pseudorapidity coverage of the PHOBOS detector. There is no significant indication of structure near midrapidity and the data surprisingly exhibit extended longitudinal scaling similar to that seen for elliptic flow and charged particle pseudorapidity density.

  14. The effect of multi-channel wide dynamic range compression, noise reduction, and the directional microphone on horizontal localization performance in hearing aid wearers.

    PubMed

    Keidser, Gitte; Rohrseitz, Kristin; Dillon, Harvey; Hamacher, Volkmar; Carter, Lyndal; Rass, Uwe; Convery, Elizabeth

    2006-10-01

    This study examined the effect that signal processing strategies used in modern hearing aids, such as multi-channel WDRC, noise reduction, and directional microphones have on interaural difference cues and horizontal localization performance relative to linear, time-invariant amplification. Twelve participants were bilaterally fitted with BTE devices. Horizontal localization testing using a 360 degrees loudspeaker array and broadband pulsed pink noise was performed two weeks, and two months, post-fitting. The effect of noise reduction was measured with a constant noise present at 80 degrees azimuth. Data were analysed independently in the left/right and front/back dimension and showed that of the three signal processing strategies, directional microphones had the most significant effect on horizontal localization performance and over time. Specifically, a cardioid microphone could decrease front/back errors over time, whereas left/right errors increased when different microphones were fitted to left and right ears. Front/back confusions were generally prominent. Objective measurements of interaural differences on KEMAR explained significant shifts in left/right errors. In conclusion, there is scope for improving the sense of localization in hearing aid users. PMID:17062498

  15. Near-infrared emitting In-rich InGaN layers grown directly on Si: Towards the whole composition range

    SciTech Connect

    Aseev, Pavel Rodriguez, Paul E. D. Soto; Gómez, Víctor J.; Alvi, Naveed ul Hassan; Calleja, Enrique; Morales, Francisco M.; Senichev, Alexander; Lienau, Christoph; and others

    2015-02-16

    The authors report compact and chemically homogeneous In-rich InGaN layers directly grown on Si (111) by plasma-assisted molecular beam epitaxy. High structural and optical quality is evidenced by transmission electron microscopy, near-field scanning optical microscopy, and X-ray diffraction. Photoluminescence emission in the near-infrared is observed up to room temperature covering the important 1.3 and 1.55 μm telecom wavelength bands. The n-InGaN/p-Si interface is ohmic due to the absence of any insulating buffer layers. This qualitatively extends the application fields of III-nitrides and allows their integration with established Si technology.

  16. Ultralong-range sounding of the ionospheric HF channel using an ionosonde/direction finder with chirp modulation of the signal

    NASA Astrophysics Data System (ADS)

    G. Vertogradov, G.; Uryadov, V. P.; Vertogradova, E. G.; Ponyatov, A. A.

    2010-08-01

    We present the results of experimental studies of propagation of short radio waves on a long transequatorial path of Laverton (Australia) — Rostov-on-Don, which were obtained with the help of an ionosonde/direction finder with chirp modulation of the signal. It is shown that conditions for propagation of anomalous signals by means of sideband reflection of radio waves from the Himalayan Hills and the Plateau of Iran and also due to scattering of radio waves from the high-latitude ionosphere of the northern hemisphere are realized on the given path. The propagation of radio waves is modeled with allowance for their scattering by anisotropic magnetic field-aligned irregularities of a high-latitude ionosphere, which are located on the northern wall of the main ionospheric trough of the F layer. It is shown that the results of the experiment agree well with the calculated data.

  17. Research Investigation Directed Toward Extending the Useful Range of the Electromagnetic Spectrum [Special Technical Report]: Further Aspects of the Theory of the Maser.

    DOE R&D Accomplishments Database

    Shimoda, K.; Wang, T. C.; Townes, C. H.

    1956-03-01

    The theory of the molecular transitions which are induced by the microwave field in a maser and the effects of various design parameters are examined in detail. It is shown that the theoretical minimum detectable beam intensity when the maser is used as a spectrometer for the 3-3 line of ammonia is about 10{sup 9} molecules/sec under typical experimental conditions. Various systematic frequency shifts and random frequency fluctuations of the maser oscillator are discussed and evaluated. The most prominent of the former are the "frequency-pulling" effect which arises from detuning of the cavity and the Doppler shift due to the asymmetrical coupling of the beam with the two travelling wave components of the standing waves which are set up in the cavity. These two effects may produce fractional shifts as large as one part in 10{sup 9}. If adequate precautions are taken, however, they can be reduced to one part in 10{sup 10} or possibly less. The random fluctuations are shown to be of the order of one part in 10{sup 13} under typical operating conditions. For molecular beams in which the electric-dipole transition is used the TM{sub 010} mode is usually the most suitable for the maser which atomic beams in which magnetic transitions are utilized, the TE{sub 011} mode is to be preferred.

  18. Direct measurement and theoretical calculation of the rate coefficient for Cl+CH3 in the range from T=202-298 K.

    PubMed

    Parker, James K; Payne, Walter A; Cody, Regina J; Nesbitt, Fred L; Stief, Louis J; Klippenstein, Stephen J; Harding, Lawrence B

    2007-02-15

    The rate coefficient has been measured under pseudo-first-order conditions for the Cl+CH3 association reaction at T=202, 250, and 298 K and P=0.3-2.0 Torr helium using the technique of discharge-flow mass spectrometry with low-energy (12-eV) electron-impact ionization and collision-free sampling. Cl and CH3 were generated rapidly and simultaneously by reaction of F with HCl and CH4, respectively. Fluorine atoms were produced by microwave discharge in an approximately 1% mixture of F2 in He. The decay of CH3 was monitored under pseudo-first-order conditions with the Cl-atom concentration in large excess over the CH3 concentration ([Cl]0/[CH3]0=9-67). Small corrections were made for both axial and radial diffusion and minor secondary chemistry. The rate coefficient was found to be in the falloff regime over the range of pressures studied. For example, at T=202 K, the rate coefficient increases from 8.4x10(-12) at P=0.30 Torr He to 1.8x10(-11) at P=2.00 Torr He, both in units of cm3 molecule-1 s-1. A combination of ab initio quantum chemistry, variational transition-state theory, and master-equation simulations was employed in developing a theoretical model for the temperature and pressure dependence of the rate coefficient. Reasonable empirical representations of energy transfer and of the effect of spin-orbit interactions yield a temperature- and pressure-dependent rate coefficient that is in excellent agreement with the present experimental results. The high-pressure limiting rate coefficient from the RRKM calculations is k2=6.0x10(-11) cm3 molecule-1 s-1, independent of temperature in the range from 200 to 300 K. PMID:17253663

  19. Experimental Studies of Selected Aqueous Electrochemical Systems Relevant for Materials Processing in the Fabrications of Microelectronic Components and Direct Alcohol Fuel Cells

    NASA Astrophysics Data System (ADS)

    Shi, Xingzhao

    A broad range of electrochemical techniques are employed in this dissertation to investigate a selected set of aqueous electrochemical systems that are relevant for materials processing in the fabrication of microelectronic devices and direct alcohol fuel cells. In terms of technical applications, this work covers three main experimental systems: (i) chemical mechanical planarization (CMP), (ii) electro-less nickel deposition, and (iii) direct alkaline glycerol fuel cells. The first two areas are related to electronic device fabrications and the third topic is related to cost-effective energy conversion. The common electrochemical aspect of these different systems is that, in all these cases the active material characteristics are governed by complex (often multi-step) reactions occurring at metal-liquid (aqueous) interfaces. Electro-analytical techniques are ideally suited for studying the detailed mechanisms of such reactions, and the present investigation is largely focused on developing adequate analytical strategies for probing these reaction mechanisms. In the fabrication of integrated circuits, certain steps of materials processing involve CMP of Al deposited on thin layers of diffusion barrier materials like Ta/TaN, Co, or Ti/TiN. A specific example of this situation is found in the processing of replacement metal gates used for high-k/metal-gate transistors. Since the commonly used barrier materials are nobler than Al, the Al interface in contact with the barrier can become prone to galvanic corrosion in the wet CMP environment. Using model systems of coupon electrodes and two specific barrier metals, Ta and Co, the electrochemical factors responsible for these corrosion effects are investigated here in a moderately acidic (pH = 4.0) abrasive-free solution. The techniques of cyclic voltammetry and impedance spectroscopy are combined with strategic measurements of galvanic currents and open circuit potentials (OCPs). L-ascorbic acid (AA) is employed as a

  20. Experimental Studies of Selected Aqueous Electrochemical Systems Relevant for Materials Processing in the Fabrications of Microelectronic Components and Direct Alcohol Fuel Cells

    NASA Astrophysics Data System (ADS)

    Shi, Xingzhao

    A broad range of electrochemical techniques are employed in this dissertation to investigate a selected set of aqueous electrochemical systems that are relevant for materials processing in the fabrication of microelectronic devices and direct alcohol fuel cells. In terms of technical applications, this work covers three main experimental systems: (i) chemical mechanical planarization (CMP), (ii) electro-less nickel deposition, and (iii) direct alkaline glycerol fuel cells. The first two areas are related to electronic device fabrications and the third topic is related to cost-effective energy conversion. The common electrochemical aspect of these different systems is that, in all these cases the active material characteristics are governed by complex (often multi-step) reactions occurring at metal-liquid (aqueous) interfaces. Electro-analytical techniques are ideally suited for studying the detailed mechanisms of such reactions, and the present investigation is largely focused on developing adequate analytical strategies for probing these reaction mechanisms. In the fabrication of integrated circuits, certain steps of materials processing involve CMP of Al deposited on thin layers of diffusion barrier materials like Ta/TaN, Co, or Ti/TiN. A specific example of this situation is found in the processing of replacement metal gates used for high-k/metal-gate transistors. Since the commonly used barrier materials are nobler than Al, the Al interface in contact with the barrier can become prone to galvanic corrosion in the wet CMP environment. Using model systems of coupon electrodes and two specific barrier metals, Ta and Co, the electrochemical factors responsible for these corrosion effects are investigated here in a moderately acidic (pH = 4.0) abrasive-free solution. The techniques of cyclic voltammetry and impedance spectroscopy are combined with strategic measurements of galvanic currents and open circuit potentials (OCPs). L-ascorbic acid (AA) is employed as a

  1. Improved ranging systems

    NASA Technical Reports Server (NTRS)

    Young, Larry E.

    1989-01-01

    Spacecraft range measurements have provided the most accurate tests, to date, of some relativistic gravitational parameters, even though the measurements were made with ranging systems having error budgets of about 10 meters. Technology is now available to allow an improvement of two orders of magnitude in the accuracy of spacecraft ranging. The largest gains in accuracy result from the replacement of unstable analog components with high speed digital circuits having precisely known delays and phase shifts.

  2. On the possibility that local mechanical forcing permits directionally-controlled long-range electron transfer along DNA-like molecular wires with no need of an external electric field. Mechanical control of electrons

    NASA Astrophysics Data System (ADS)

    Chetverikov, Alexander P.; Ebeling, Werner; Lakhno, Viktor D.; Shigaev, Alexey S.; Velarde, Manuel G.

    2016-04-01

    It is shown that in DNA-like molecules containing added, excess charges, such as electrons and holes (cation-radicals), it is possible by highly energetic, local, mechanical excitation at definite places of the chain to control the creation of breathers/bubbles and hence to control the long-range transfer of charges moving along the chain in a definite given direction with no external electric field needed.

  3. UV, IR, NIR, Direct Injection MS Spectral Fingerprinting, and Analysis of Variance-Principal Component Analysis: Tools for Categorization of Food Materials Grown in a Different Environment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetics and environmental conditions (such as rainfall, pests, soil, irrigation levels, and fertilization) will lead to chemical differences in plant materials. Simple and inexpensive spectral fingerprinting (UV, IR, NIR, and Direct MS) methods are described that allow differentiation of plant mat...

  4. A Cation-Directed Enantioselective Sulfur-Mediated Michael/Mannich Three-Component Domino Reaction involving Chalcones as Michael Acceptors.

    PubMed

    Ding, Ran; Zheng, Bo; Wang, Yan; Peng, Yungui

    2015-09-01

    A new approach has been developed for an asymmetric sulfur-mediated three-component intermolecular Michael/Mannich domino reaction using chalcones as Michael acceptors. This reaction is catalyzed by chiral quaternary ammonium salts derived from modified quinine and provides facile access to complex sulfur-containing compounds with three contiguous stereogenic centers in yields of up to 93%, with 95:5 dr and 95% ee. These compounds were further elaborated to give the equivalent of a chiral aza-Morita-Baylis-Hillman reaction involving chalcones and azetidines bearing four chiral centers. PMID:26295594

  5. Exploring hydrocarbon-bearing shale formations with multi-component seismic technology and evaluating direct shear modes produced by vertical-force sources

    NASA Astrophysics Data System (ADS)

    Alkan, Engin

    It is essential to understand natural fracture systems embedded in shale-gas reservoirs and the stress fields that influence how induced fractures form in targeted shale units. Multicomponent seismic technology and elastic seismic stratigraphy allow geologic formations to be better images through analysis of different S-wave modes as well as the P-wave mode. Significant amounts of energy produced by P-wave sources radiate through the Earth as downgoing SV-wave energy. A vertical-force source is an effective source for direct SV radiation and provides a pure shear-wave mode (SV-SV) that should reveal crucial information about geologic surfaces located in anisotropic media. SV-SV shear wave modes should carry important information about petrophysical characteristics of hydrocarbon systems that cannot be obtained using other elastic-wave modes. Regardless of the difficulties of extracting good-quality SV-SV signal, direct shear waves as well as direct P and converted S energy should be accounted for in 3C seismic studies. Acquisition of full-azimuth seismic data and sampling data at small intervals over long offsets are required for detailed anisotropy analysis. If 3C3D data can be acquired with improved signal-to-noise ratio, more uniform illumination of targets, increased lateral resolution, more accurate amplitude attributes, and better multiple attenuation, such data will have strong interest by the industry. The objectives of this research are: (1) determine the feasibility of extracting direct SV-SV common-mid-point sections from 3-C seismic surveys, (2) improve the exploration for stratigraphic traps by developing systematic relationship between petrophysical properties and combinations of P and S wave modes, (3) create compelling examples illustrating how hydrocarbon-bearing reservoirs in low-permeable rocks (particularly anisotropic shale formations) can be better characterized using different Swave modes (P-SV, SV-SV) in addition to the conventional P

  6. Range Ecosystems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    After more than two hundred years, grazing remains California’s most extensive land use. The ‘Range Ecosystems’ chapter in the ‘Ecosystems of California’ sourcebook provides an integrated picture of the biophysical, social, and economic aspects of lands grazed by livestock in the state. Grazing mana...

  7. Efficacy of a multi-metric fish index as an analysis tool for the transitional fish component of the Water Framework Directive.

    PubMed

    Coates, Steve; Waugh, Adam; Anwar, Alice; Robson, Matthew

    2007-01-01

    The WFD has introduced an international commitment to assess the ecological status of transitional waters (TWs), within which fish communities are a key biological monitoring component. The Transitional Fish Classification Index (TFCI) outlined in this paper uses 10 ecological measures to analyse fish populations caught from various ecological niches using a variety of gear types within the Thames estuary. These reach and method-specific communities are then compared to a reference population created from a 'healthy' population from TWs of a similar type. The results indicate a progressive downstream increase the quality of fish communities, consistent with previous work; variation between methods can be accounted for by gear selectivity. Overall, the TFCI is an effective communication tool for converting ecological information into an easily understood format for managers, policy makers and the general public. PMID:17056072

  8. A novel strategy for dissecting goal-directed action and arousal components of motivated behavior with a progressive hold-down task.

    PubMed

    Bailey, Matthew R; Jensen, Greg; Taylor, Kathleen; Mezias, Chris; Williamson, Cait; Silver, Rae; Simpson, Eleanor H; Balsam, Peter D

    2015-06-01

    Motivation serves 2 important functions: It guides actions to be goal-directed, and it provides the energy and vigor required to perform the work necessary to meet those goals. Dissociating these 2 processes with existing behavioral assays has been a challenge. In this article, we report a novel experimental strategy to distinguish the 2 processes in mice. First, we characterize a novel motivation assay in which animals must hold down a lever for progressively longer intervals to earn each subsequent reward; we call this the progressive hold-down (PHD) task. We find that performance on the PHD task is sensitive to both food deprivation level and reward value. Next, we use a dose of methamphetamine (METH) 1.0 mg/kg, to evaluate behavior in both the progressive ratio (PR) and PHD tasks. Treatment with METH leads to more persistent lever pressing for food rewards in the PR. In the PHD task, we found that METH increased arousal, which leads to numerous bouts of hyperactive responding but neither increases nor impairs goal-directed action. The results demonstrate that these tools enable a more precise understanding of the underlying processes being altered in manipulations that alter motivated behavior. PMID:26030428

  9. Direct observation of a sin(2φ) component in the current-phase relation of superconductor-ferromagnet-superconductor (SFS) Josephson junctions

    NASA Astrophysics Data System (ADS)

    Stoutimore, M. J. A.; Rusanov, A. Yu.; Bahr, D. J.; Oboznov, V. A.; Bolginov, V. V.; Rossolenko, A. N.; Ryazanov, V. V.; van Harlingen, D. J.

    2008-03-01

    We present direct measurements of the current-phase relation (CPR) of SFS Josephson junctions in an rf-SQUID geometry. The junctions are fabricated from Nb-Cu47Ni53-Nb trilayers with a junction area of 2x2 μm^2 and a CuNi thickness of 7 nm. By measuring the magnetic flux through the rf-SQUID as a function of applied current, we observe transitions between an ordinary 0-Josephson junction state and a π-junction state characterized by a phase difference of π in the ground state occurring at temperatures between 1.5 K and 3.5 K. Near this temperature crossover, we observe period-doubling of the CPR indicating the existence of a term proportional to sin(2φ). Work is underway to determine if this signifies an intrinsic second-order tunneling mechanism or is the result of junction inhomogeneities.

  10. Balloon-borne direct search for ionizing massive particles as a component of the galactic halo dark matter (The Arizona-IMAX Collaboration)

    NASA Astrophysics Data System (ADS)

    McGuire, P. C.; Bowen, T.; Barker, D. L.; Halverson, P. G.; Kendall, K. R.; Metcalfe, T. S.; Norton, R. S.; Pifer, A. E.; Barbier, L. M.; Christian, E. R.; Krombel, K. E.; Mitchell, J. W.; Ormes, J. F.; Streitmatter, R. E.; Davis, A. J.; Labrador, A. W.; Mewaldt, R. A.; Schindler, S. M.; Golden, R. L.; Stochaj, S. J.; Webber, W. R.; Arizona-IMAX Collaboration

    1995-07-01

    A dark matter (DM) search experiment was flown on the IMAX balloon payload to search for a possible minor component of the dark matter in the Galactic halo: ionizing massive particles (IMPs) (mx>~104 GeV/c2) that cannot penetrate the atmosphere due to their low-velocities and high energy-loss. The DM search experiment consisted of a delayed coincidence between four large plastic scintillation detectors arranged in a vertical stack. In order to search for ultra-slow particles which do not slow down in the IMAX telescope, the experiment contained TDCs which measured the time-delay Ti,i+1∈(0.3, 14.0) μs between hits in successive counters to ~2% precision. We present IMP flux limits for non-slowing IMPs and also for IMPs which slow down significantly within the IMAX telescope. This experiment effectively closes much of a previously unconstrained ``window'' in the mass/cross-section joint parameter spaces for massive particles as the dominant halo DM.

  11. Automatic range selector

    DOEpatents

    McNeilly, Clyde E.

    1977-01-04

    A device is provided for automatically selecting from a plurality of ranges of a scale of values to which a meter may be made responsive, that range which encompasses the value of an unknown parameter. A meter relay indicates whether the unknown is of greater or lesser value than the range to which the meter is then responsive. The rotatable part of a stepping relay is rotated in one direction or the other in response to the indication from the meter relay. Various positions of the rotatable part are associated with particular scales. Switching means are sensitive to the position of the rotatable part to couple the associated range to the meter.

  12. Killing Range

    PubMed Central

    Asal, Victor; Rethemeyer, R. Karl; Horgan, John

    2015-01-01

    This paper presents an analysis of the Provisional Irish Republican Army's (PIRA) brigade level behavior during the Northern Ireland Conflict (1970-1998) and identifies the organizational factors that impact a brigade's lethality as measured via terrorist attacks. Key independent variables include levels of technical expertise, cadre age, counter-terrorism policies experienced, brigade size, and IED components and delivery methods. We find that technical expertise within a brigade allows for careful IED usage, which significantly minimizes civilian casualties (a specific strategic goal of PIRA) while increasing the ability to kill more high value targets with IEDs. Lethal counter-terrorism events also significantly affect a brigade's likelihood of killing both civilians and high-value targets but in different ways. Killing PIRA members significantly decreases IED fatalities but also significantly decreases the possibility of zero civilian IED-related deaths in a given year. Killing innocent Catholics in a Brigade's county significantly increases total and civilian IED fatalities. Together the results suggest the necessity to analyze dynamic situational variables that impact terrorist group behavior at the sub-unit level. PMID:25838603

  13. Tracking and identification of antibacterial components in the essential oil of Tanacetum vulgare L. by the combination of high-performance thin-layer chromatography with direct bioautography and mass spectrometry.

    PubMed

    Móricz, Ágnes M; Häbe, Tim T; Böszörményi, Andrea; Ott, Péter G; Morlock, Gertrud E

    2015-11-27

    Two tansy (Tanacetum vulgare L.) essential oils were obtained by steam distillation of the capitula with subsequent liquid-liquid extraction (oil 1) or with use of an auxiliary phase for the trapping of the steam components (oil 2). These oils were investigated against Bacillus subtilis F1276, B. subtilis spizizenii (DSM 618), Xanthomonas euvesicatoria, Pseudomonas syringae pv. maculicola, Ralstonia solanacearum strain GMI1000 and Aliivibrio fischeri, using the coupling of high-performance thin-layer chromatography to direct bioautography (HPTLC-DB). Using this method with the potato and tomato pathogen R. solanacearum is shown for the first time. Due to the advanced extraction process, oil 2 was richer in components and provided more inhibition zones. The main bioactive components were identified by scanning HPTLC-Direct Analysis in Real Time mass spectrometry (HPTLC-DART-MS) and solid-phase microextraction gas chromatography electron impact MS (SPME-GC-EI-MS) as cis- and trans-chrysanthenol as well as trans-chrysanthenyl acetate. cis-Chrysanthenol exhibited antibacterial effects against all tested bacteria, whereas trans-chrysanthenol inhibited B. subtilis, R. solanacearum and A. fischeri. trans-Chrysanthenyl acetate was an inhibitor for X. euvesicatoria, R. solanacearum and A. fischeri. Although HPTLC-DART-MS resulted in a comparable fragmentation, the ionization characteristics and the recorded mass spectra clearly showed that DART is a softer ionization technique than EI. It is also more affected by ambient conditions and thus prone to additional oxidation products. PMID:26499972

  14. Direct characterization of the energy level alignments and molecular components in an organic hetero-junction by integrated photoemission spectroscopy and reflection electron energy loss spectroscopy analysis

    NASA Astrophysics Data System (ADS)

    Yun, Dong-Jin; Shin, Weon-Ho; Bulliard, Xavier; Park, Jong Hwan; Kim, Seyun; Chung, Jae Gwan; Kim, Yongsu; Heo, Sung; Kim, Seong Heon

    2016-08-01

    A novel, direct method for the characterization of the energy level alignments at bulk-heterojunction (BHJ)/electrode interfaces on the basis of electronic spectroscopy measurements is proposed. The home-made in situ photoemission system is used to perform x-ray/ultraviolet photoemission spectroscopy (XPS/UPS), reflection electron energy loss spectroscopy (REELS) and inverse photoemission spectroscopy of organic-semiconductors (OSCs) deposited onto a Au substrate. Through this analysis system, we are able to obtain the electronic structures of a boron subphthalocyanine chloride:fullerene (SubPC:C60) BHJ and those of the separate OSC/electrode structures (SubPC/Au and C60/Au). Morphology and chemical composition analyses confirm that the original SubPC and C60 electronic structures remain unchanged in the electrodes prepared. Using this technique, we ascertain that the position and area of the nearest peak to the Fermi energy (EF = 0 eV) in the UPS (REELS) spectra of SubPC:C60 BHJ provide information on the highest occupied molecular orbital level (optical band gap) and combination ratio of the materials, respectively. Thus, extracting the adjusted spectrum from the corresponding SubPC:C60 BHJ UPS (REELS) spectrum reveals its electronic structure, equivalent to that of the C60 materials. This novel analytical approach allows complete energy-level determination for each combination ratio by separating its electronic structure information from the BHJ spectrum.

  15. Direct characterization of the energy level alignments and molecular components in an organic hetero-junction by integrated photoemission spectroscopy and reflection electron energy loss spectroscopy analysis.

    PubMed

    Yun, Dong-Jin; Shin, Weon-Ho; Bulliard, Xavier; Park, Jong Hwan; Kim, Seyun; Chung, Jae Gwan; Kim, Yongsu; Heo, Sung; Kim, Seong Heon

    2016-08-26

    A novel, direct method for the characterization of the energy level alignments at bulk-heterojunction (BHJ)/electrode interfaces on the basis of electronic spectroscopy measurements is proposed. The home-made in situ photoemission system is used to perform x-ray/ultraviolet photoemission spectroscopy (XPS/UPS), reflection electron energy loss spectroscopy (REELS) and inverse photoemission spectroscopy of organic-semiconductors (OSCs) deposited onto a Au substrate. Through this analysis system, we are able to obtain the electronic structures of a boron subphthalocyanine chloride:fullerene (SubPC:C60) BHJ and those of the separate OSC/electrode structures (SubPC/Au and C60/Au). Morphology and chemical composition analyses confirm that the original SubPC and C60 electronic structures remain unchanged in the electrodes prepared. Using this technique, we ascertain that the position and area of the nearest peak to the Fermi energy (EF = 0 eV) in the UPS (REELS) spectra of SubPC:C60 BHJ provide information on the highest occupied molecular orbital level (optical band gap) and combination ratio of the materials, respectively. Thus, extracting the adjusted spectrum from the corresponding SubPC:C60 BHJ UPS (REELS) spectrum reveals its electronic structure, equivalent to that of the C60 materials. This novel analytical approach allows complete energy-level determination for each combination ratio by separating its electronic structure information from the BHJ spectrum. PMID:27420635

  16. Systematic Study of Rayleigh-Taylor Growth in Directly Driven Plastic Targets in a Laser-Intensity Range from ~2 x 10^14 to ~1.5 x 10^15 W/cm^2

    SciTech Connect

    Smalyuk, V.A.; Hu, S.X.; Goncharov, V.N.; Meyerhofer, D.D.; Sangster, T.C.; Stoeckl, C.; Yaakobi, B.

    2008-09-05

    Direct-drive, Rayleigh–Taylor (RT) growth experiments were performed using planar plastic targets on the OMEGA Laser Facility [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)] at laser intensities between ~2 x 10^14 and ~1.5 x 10^15 W/cm^2. The primary purpose of the experiments was to test fundamental physics in hydrocodes at the range of drive intensities relevant to ignition designs. The target acceleration was measured with a streak camera using side-on, x-ray radiography, while RT growth was measured with a framing camera using face-on radiography. In a laser-intensity range from 2 to 5 x 10^14 W/cm^2, the measured RT growth agrees well with two-dimensional simulations, based on a local model of thermal-electron transport. The RT growth at drive intensities above ~1.0 x 10^15 W/cm^2 was strongly stabilized compared to the local model predictions. The experiments demonstrate that standard simulations, based on a local model of electron thermal transport, break down at peak intensities of ignition designs, although they work well at lower intensities. These results also imply that direct-drive ignition targets are significantly more stable than previously calculated using local electron-transport models at peak intensities of ignition designs. The preheating effects by nonlocal electron transport and hot electrons were identified as some of the stabilizing mechanisms.

  17. Systematic study of Rayleigh-Taylor growth in directly driven plastic targets in a laser-intensity range from {approx}2x10{sup 14} to {approx}1.5x10{sup 15} W/cm{sup 2}

    SciTech Connect

    Smalyuk, V. A.; Hu, S. X.; Goncharov, V. N.; Meyerhofer, D. D.; Sangster, T. C.; Stoeckl, C.; Yaakobi, B.

    2008-08-15

    Direct-drive, Rayleigh-Taylor (RT) growth experiments were performed using planar plastic targets on the OMEGA Laser Facility [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)] at laser intensities between {approx}2x10{sup 14} and {approx}1.5x10{sup 15} W/cm{sup 2}. The primary purpose of the experiments was to test fundamental physics in hydrocodes at the range of drive intensities relevant to ignition designs. The target acceleration was measured with a streak camera using side-on, x-ray radiography, while RT growth was measured with a framing camera using face-on radiography. In a laser-intensity range from 2 to 5x10{sup 14} W/cm{sup 2}, the measured RT growth agrees well with two-dimensional simulations, based on a local model of thermal-electron transport. The RT growth at drive intensities above {approx}1.0x10{sup 15} W/cm{sup 2} was strongly stabilized compared to the local model predictions. The experiments demonstrate that standard simulations, based on a local model of electron thermal transport, break down at peak intensities of ignition designs, although they work well at lower intensities. These results also imply that direct-drive ignition targets are significantly more stable than previously calculated using local electron-transport models at peak intensities of ignition designs. The preheating effects by nonlocal electron transport and hot electrons were identified as some of the stabilizing mechanisms.

  18. Fast heating induced impulse halogenation of refractory sample components in electrothermal atomic absorption spectrometry by direct injection of a liquid halogenating agent.

    PubMed

    György, Krisztina; Ajtony, Zsolt; Van Meel, Katleen; Van Grieken, René; Czitrovszky, Aladár; Bencs, László

    2011-09-15

    A novel electrothermal atomic absorption spectrometry (ETAAS) method was developed for the halogenation of refractory sample components (Er, Nd and Nb) of lithium niobate (LiNbO(3)) and bismuth tellurite (Bi(2)TeO(5)) optical single crystals to overcome memory effects and carry-over. For this purpose, the cleaning step of a regular graphite furnace heating program was replaced with a halogenation cycle. In this cycle, after the graphite tube cooled to room temperature, a 20 μL aliquot of liquid carbon tetrachloride (CCl(4)) was dispensed with a conventional autosampler into the graphite tube. The CCl(4) was partially dried at 80°C under the mini-flow (40 cm(3) min(-1)) condition of the Ar internal furnace gas (IFG), then the residue was decomposed (pyrolyzed) by fast furnace heating at 1900-2100°C under interrupted flow of the IFG. This step was followed by a clean-out stage at 2100°C under the maximum flow of the IFG. The advantage of the present method is that it does not require any alteration to the graphite furnace gas supply system in contrast to most of the formerly introduced halogenation techniques. The effectiveness of the halogenation method was verified with the determination of Er and Nd dopants in the optical crystals. In these analyses, a sensitivity decrease was observed, which was likely due to the enhanced deterioration of the graphite tube surface. Therefore, the application of mathematical correction (resloping) of the calibration was also required. The calibration curves were linear up to 1.5 and 10 μmol L(-1) for Er and Nd, respectively. Characteristic masses of 18 and 241 pg and the limit of detection (LOD) values of 0.017 and 0.27 μmol L(-1) were found for Er and Nd, respectively. These LOD data correspond to 0.68 μmol mol(-1) Er and 11 μmol mol(-1) Nd in solid bismuth tellurite samples. The analytical results were compared with those obtained by a conventional ETAAS method and validated with X-ray fluorescence spectrometry analysis

  19. Direct conversion of algal biomass to biofuel

    DOEpatents

    Deng, Shuguang; Patil, Prafulla D; Gude, Veera Gnaneswar

    2014-10-14

    A method and system for providing direct conversion of algal biomass. Optionally, the method and system can be used to directly convert dry algal biomass to biodiesels under microwave irradiation by combining the reaction and combining steps. Alternatively, wet algae can be directly processed and converted to fatty acid methyl esters, which have the major components of biodiesels, by reacting with methanol at predetermined pressure and temperature ranges.

  20. Telemetry-Based Ranging

    NASA Technical Reports Server (NTRS)

    Hamkins, Jon; Vilnrotter, Victor A.; Andrews, Kenneth S.; Shambayati, Shervin

    2011-01-01

    A telemetry-based ranging scheme was developed in which the downlink ranging signal is eliminated, and the range is computed directly from the downlink telemetry signal. This is the first Deep Space Network (DSN) ranging technology that does not require the spacecraft to transmit a separate ranging signal. By contrast, the evolutionary ranging techniques used over the years by NASA missions, including sequential ranging (transmission of a sequence of sinusoids) and PN-ranging (transmission of a pseudo-noise sequence) whether regenerative (spacecraft acquires, then regenerates and retransmits a noise-free ranging signal) or transparent (spacecraft feeds the noisy demodulated uplink ranging signal into the downlink phase modulator) relied on spacecraft power and bandwidth to transmit an explicit ranging signal. The state of the art in ranging is described in an emerging CCSDS (Consultative Committee for Space Data Systems) standard, in which a pseudo-noise (PN) sequence is transmitted from the ground to the spacecraft, acquired onboard, and the PN sequence is coherently retransmitted back to the ground, where a delay measurement is made between the uplink and downlink signals. In this work, the telemetry signal is aligned with the uplink PN code epoch. The ground station computes the delay between the uplink signal transmission and the received downlink telemetry. Such a computation is feasible because symbol synchronizability is already an integral part of the telemetry design. Under existing technology, the telemetry signal cannot be used for ranging because its arrival-time information is not coherent with any Earth reference signal. By introducing this coherence, and performing joint telemetry detection and arrival-time estimation on the ground, a high-rate telemetry signal can provide all the precision necessary for spacecraft ranging.

  1. Technical support document: Energy efficiency standards for consumer products: Room air conditioners, water heaters, direct heating equipment, mobile home furnaces, kitchen ranges and ovens, pool heaters, fluorescent lamp ballasts and television sets. Volume 1, Methodology

    SciTech Connect

    Not Available

    1993-11-01

    The Energy Policy and Conservation Act (P.L. 94-163), as amended, establishes energy conservation standards for 12 of the 13 types of consumer products specifically covered by the Act. The legislation requires the Department of Energy (DOE) to consider new or amended standards for these and other types of products at specified times. DOE is currently considering amending standards for seven types of products: water heaters, direct heating equipment, mobile home furnaces, pool heaters, room air conditioners, kitchen ranges and ovens (including microwave ovens), and fluorescent light ballasts and is considering establishing standards for television sets. This Technical Support Document presents the methodology, data, and results from the analysis of the energy and economic impacts of the proposed standards. This volume presents a general description of the analytic approach, including the structure of the major models.

  2. Brain components

    MedlinePlus Videos and Cool Tools

    The brain is composed of more than a thousand billion neurons. Specific groups of them, working in concert, provide ... of information. The 3 major components of the brain are the cerebrum, cerebellum, and brain stem. The ...

  3. Range Imaging without Moving Parts

    NASA Technical Reports Server (NTRS)

    Blair, J. Bryan; Scott, V. Stanley, III; Ramos-Izquierdo, Luis

    2008-01-01

    Range-imaging instruments of a type now under development are intended to generate the equivalent of three-dimensional images from measurements of the round-trip times of flight of laser pulses along known directions. These instruments could also provide information on characteristics of targets, including roughnesses and reflectivities of surfaces and optical densities of such semi-solid objects as trees and clouds. Unlike in prior range-imaging instruments based on times of flight along known directions, there would be no moving parts; aiming of the laser beams along the known directions would not be accomplished by mechanical scanning of mirrors, prisms, or other optical components. Instead, aiming would be accomplished by using solid-state devices to switch input and output beams along different fiber-optic paths. Because of the lack of moving parts, these instruments could be extraordinarily reliable, rugged, and long-lasting. An instrument of this type would include an optical transmitter that would send out a laser pulse along a chosen direction to a target. An optical receiver coaligned with the transmitter would measure the temporally varying intensity of laser light reflected from the target to determine the distance and surface characteristics of the target. The transmitter would be a combination of devices for generating precise directional laser illumination. It would include a pulsed laser, the output of which would be coupled into a fiber-optic cable with a fan-out and solid-state optical switches that would enable switching of the laser beam onto one or more optical fibers terminated at known locations in an array on a face at the focal plane of a telescope. The array would be imaged by the telescope onto the target space. The receiver optical system could share the aforementioned telescope with the transmitter or could include a separate telescope aimed in the same direction as that of the transmitting telescope. In either case, light reflected

  4. Evidence for an Early Archean component in the Middle to Late Archean gneisses of the Wind River Range, west-central Wyoming: conventional and ion microprobe U-Pb data

    USGS Publications Warehouse

    Aleinikoff, J.N.; Williams, I.S.; Compston, W.; Stuckless, J.S.; Worl, R.G.

    1989-01-01

    Gneissic rocks that are basement to the Late Archean granites comprising much of the Wind River Range, west-central Wyoming, have been dated by the zircon U-Pb method using both conventional and ion microprobe techniques. A foliated hornblende granite gneiss member from the southern border of the Bridger batholith is 2670??13 Ma. Zircons from a granulite just north of the Bridger batholith are equant and faceted, a typical morphology for zircon grown under high grade metamorphic conditions. This granulite, which may be related to a second phase of migmatization in the area, is 2698??8 Ma. South of the Bridger batholith, zircons from a granulite (charnockite), which is related to an earlier phase of migmatization in the Range, yield a discordia with intercept ages of about 2.3 and 3.3 Ga. However, ion microprobe analyses of single zircon grains indicate that this rock contains several populations of zircon, ranging in age from 2.67 to about 3.8 Ga. Based on zircon morphology and regional geologic relationships, we interpret the data as indicating an age of ???3.2 Ga for the first granulite metamorphism and migmatization. Older, possibly xenocrystic zircons give ages of ???3.35, 3.65 and ???3.8 Ga. Younger zircons grew at 2.7 and 2.85 Ga in response to events, including the second granulite metamorphism at 2.7 Ga, that culminated in the intrusion of the Bridger batholith and migmatization at 2.67 Ga. These data support the field and petrographic evidence for two granulite events and provide some temporal constraints for the formation of continental crust in the Early and Middle Archean in the Wyoming Province. ?? 1989 Springer-Verlag.

  5. Home range and travels

    USGS Publications Warehouse

    Stickel, L.F.

    1968-01-01

    . Peromyscus generally used and maintained several or many different home sites and refuges in various parts of their home ranges, and frequently shifted about so that their principal activities centered on different sets of holes at different times. Once established, many Peromyscus remained in the same general area for a long time, perhaps for the duration of their lives. Extent of their travels in different directions and intensity of use of different portions of their home ranges varied within a general area in response to habitat changes, loss of neighbors, or other factors. Various authors have obtained both direct and indirect evidence of territoriality, in some degree, among certain species of Peromyscus. Young mice dispersed from their birth sites to establish home ranges of their own. Adults also sometimes left their home areas; some re-established elsewhere; others returned after exploratory travels. Most populations contained a certain proportion of transients; these may have been wanderers or individuals exploring out from established home ranges or seeking new ones. When areas were depopulated by removal trapping, other Peromyscus invaded. Invasion rates generally followed seasonal trends of reproduction and population density. Peromyscus removed from their home areas and released elsewhere returned home from various distances, but fewer returned from greater distances than from nearby; speed of return increased with successive trials. The consensus from present evidence is that ho-ming is made possible by a combination of random wandering and familiarity with a larger area than the day-to-day range. Records of juvenile wanderings during the dispersal phase and of adult explorations very nearly encompassed the distances over which any substantial amount of successful homing occurred. Methods of measuring sizes of home ranges and the limitations of these measurements were discussed in brief synopsis. It was co

  6. X-ray mass attenuation coefficients and imaginary components of the atomic form factor of zinc over the energy range of 7.2-15.2 keV

    SciTech Connect

    Rae, Nicholas A.; Chantler, Christopher T.; Barnea, Zwi; Jonge, Martin D. de; Tran, Chanh Q.; Hester, James R.

    2010-02-15

    The x-ray mass attenuation coefficients of zinc are measured in a high-accuracy experiment between 7.2 and 15.2 keV with an absolute accuracy of 0.044% and 0.197%. This is the most accurate determination of any attenuation coefficient on a bending-magnet beamline and reduces the absolute uncertainty by a factor of 3 compared to earlier work by advances in integrated column density determination and the full-foil mapping technique described herein. We define a relative accuracy of 0.006%, which is not the same as either the precision or the absolute accuracy. Relative accuracy is the appropriate parameter for standard implementation of analysis of near-edge spectra. Values of the imaginary components f'' of the x-ray form factor of zinc are derived. Observed differences between the measured mass attenuation coefficients and various theoretical calculations reach a maximum of about 5% at the absorption edge and up to 2% further than 1 keV away from the edge. The measurements invite improvements in the theoretical calculations of mass attenuation coefficients of zinc.

  7. Components for solar energy

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A requirement for the direct technological utilization of solar energy is a device for capturing and absorbing the available sunlight. These devices are commonly termed collectors. Because of the highly variable nature of sunlight, a facility for storing the collected energy is often essential. A device for direct conversion of light into electricity, which depends for operation on incident sunlight, is the photovoltaic cell. These components for solar energy systems are considered.

  8. On the Dynamical Evolution of H II Regions: An Investigation of the Ionized Component of W4, a Galactic Chimney Candidate. I. Kinematics and Dynamics in the Latitude Range 0° <= b <= 3°

    NASA Astrophysics Data System (ADS)

    Lagrois, Dominic; Joncas, Gilles

    2009-02-01

    Fabry-Perot interferometry was used to obtain an Hα survey of the most emissive part of W4, a giant superbubble/H II region located in the Perseus arm. Presented by Normandeau and colleagues as an H I cavity aiming away from the Galactic plane, the void has been morphologically interpreted as a Galactic chimney candidate in interaction with the Galactic corona. We present the kinematical results of nearly five million Hα spectra obtained in the southern portion of the nebula (0° <= b <= 3°). Many small-scale radial velocity gradients are detected in the embedded ionized component and are attributed to the photoionization of dense, mostly molecular, fragments found either in or at the periphery of the expanding supershell. The mean local standard of rest radial velocity associated with our Hα survey is found at -42.565 ± 5.204 (1σ) km s-1, redshifted by roughly 5 km s-1 from the molecular material found in the vicinity of the large superbubble. Investigation of the Hα line-width measurements has shown W4-south to fall in a transient regime between low velocity dispersions characteristic of small-size Galactic H II regions and supersonic line widths associated with supergiant extragalactic structures. The overall kinematics of W4-south is best explained with the Champagne model for the dynamical evolution of H II regions where at least 10 independent gas flows crisscross the nebula. For the first time, a Champagne flow is seen coming to an end within a nebula, mingling with the surrounding ionized gas. The nature (molecular versus atomic) of the neutral material, prone to erosion, is critical as it leads to much different kinematical interpretations. W4-south appears as a text book example of the last stage in the life of a giant molecular cloud complex.

  9. Time-Variable Gravity from Satellite-Laser-Ranging and Doppler Measurements: An Update on the Low-degree components as well as the connections with Geophysical/Climatic Processes

    NASA Technical Reports Server (NTRS)

    Cox, Christopher M.; Chao, Benjamin F.; Au, Andrew Y.; Boy, J.-P.

    2003-01-01

    The oblateness of the Earth's gravity field, 52, has long been observed to undergo a slight decrease due to post-glacial rebound of the mantle. Sometime around 1998 this trend reversed quite suddenly. This reversal persisted until 2001, at which point the atmosphere-corrected time series appears to have reversed yet again. Presently, the time series appears to be returning to the value that would nominally have been reached had the anomaly not occurred. This anomaly signifies a large interannual change in global mass distribution whose J2 effect overshadows that of the post-glacial rebound over such timescales. A number of possible causes have been considered, with oceanic mass redistribution as the leading candidate although other effects, such as glacial melting and core effects may be contributing. The amount by which J2 returns to it's nominal value provides a valuable constraint on the separation of the causes, and will be considered. We will present our latest Satellite Laser Ranging and DORIS Doppler derived time series for J2, and various other low-degree harmonic terms, as well as our investigations into the causes. In addition, we will show the comparison of the J2 results with those derived from CHAMP, as computed at NASA GSFC, and the recently released GRACE gravity model.

  10. Institutional Long-Range Planning.

    ERIC Educational Resources Information Center

    Bolin, John G.

    This booklet presents a general outline for conducting a long-range planning study that can be adapted for use by any institution of higher education. The basic components of an effective long-range plan should include: (1) purposes of the plan, which define the scope of the study and provide the setting in which it will be initiated; (2) a set of…

  11. Component separations.

    PubMed

    Heller, Lior; McNichols, Colton H; Ramirez, Oscar M

    2012-02-01

    Component separation is a technique used to provide adequate coverage for midline abdominal wall defects such as a large ventral hernia. This surgical technique is based on subcutaneous lateral dissection, fasciotomy lateral to the rectus abdominis muscle, and dissection on the plane between external and internal oblique muscles with medial advancement of the block that includes the rectus muscle and its fascia. This release allows for medial advancement of the fascia and closure of up to 20-cm wide defects in the midline area. Since its original description, components separation technique underwent multiple modifications with the ultimate goal to decrease the morbidity associated with the traditional procedure. The extensive subcutaneous lateral dissection had been associated with ischemia of the midline skin edges, wound dehiscence, infection, and seroma. Although the current trend is to proceed with minimally invasive component separation and to reinforce the fascia with mesh, the basic principles of the techniques as described by Ramirez et al in 1990 have not changed over the years. Surgeons who deal with the management of abdominal wall defects are highly encouraged to include this technique in their collection of treatment options. PMID:23372455

  12. Hyperfrequency components

    NASA Astrophysics Data System (ADS)

    1994-09-01

    The document has a collection of 19 papers (11 on technologies, 8 on applications) by 26 authors and coauthors. Technological topics include: evolution from conventional HEMT's double heterojunction and planar types of pseudomorphic HEMT's; MMIC R&D and production aspects for very-low-noise, low-power, and very-low-noise, high-power applications; hyperfrequency CAD tools; parametric measurements of hyperfrequency components on plug-in cards for design and in-process testing uses; design of Class B power amplifiers and millimetric-wave, bigrid-transistor mixers, exemplifying combined use of three major types of physical simulation in electrical modeling of microwave components; FET's for power amplification at up to 110 GHz; production, characterization, and nonlinear applications of resonant tunnel diodes. Applications topics include: development of active modules for major European programs; tubes versus solid-state components in hyperfrequency applications; status and potentialities of national and international cooperative R&D on MMIC's and CAD of hyperfrequency circuitry; attainable performance levels in multifunction MMIC applications; state of the art relative of MESFET power amplifiers (Bands S, C, X, Ku); creating a hyperfrequency functions library, of parametrizable reference cells or macrocells; and design of a single-stage, low-noise, band-W amplifier toward development of a three-stage amplifier.

  13. A Single-blind, Placebo-controlled, Dose-ranging Trial of Oral Hepatic-directed Vesicle Insulin Add-on to Oral Antidiabetic Treatment in Patients With Type 2 Diabetes Mellitus

    PubMed Central

    Rosenberg, Len N.; Schwartz, Sherwyn L.; Lau, John R.; Gana, Theophilus J.

    2014-01-01

    The dose response of postprandial plasma glucose (PPG) to add-on, premeal oral hepatic-directed vesicle-insulin (HDV-I), an investigational lipid bio-nanoparticle hepatocyte-targeted insulin delivery system, was evaluated in a 3-test-meal/day model in type 2 diabetes patients. The single-blind, placebo-controlled, dose-escalating trial enrolled 6 patients with HbA1c 8.6 ± 2.0% (70.0 ± 21.9 mmol/mol) and on stable metformin therapy. Patients received oral HDV-I capsules daily 30 minutes before breakfast, lunch, and dinner as follows: placebo capsules, 0.05, 0.1, 0.2, and 0.4 U/kg on days 1, 2, 3, 4, and 5, respectively. Outcome measures were PPG and incremental PPG area under the concentration-time curve (AUC). All 4 doses of oral HDV-I statistically significantly lowered mean PPG (P ≤ .0110 each) and incremental PPG (P ≤ .0352 each) AUC compared to placebo. A linear dose response was not observed. The 0.05 U/kg dose was the minimum effective dose in the dosage range studied. Three adverse events unrelated to treatment were observed. Add-on oral HDV-I 0.05-0.4 U/kg significantly lowered PPG excursions and the dose response curve was flat. These results are consistent with the lack of a linear dose response between portal and systemic plasma insulin concentrations in previous animal and human studies. Oral HDV-I was safe and well tolerated. PMID:24876619

  14. Laser Micromachining Fabrication of THz Components

    NASA Technical Reports Server (NTRS)

    DrouetdAubigny, C.; Walker, C.; Jones, B.; Groppi, C.; Papapolymerou, J.; Tavenier, C.

    2001-01-01

    Laser micromachining techniques can be used to fabricate high-quality waveguide structures and quasi-optical components to micrometer accuracies. Successful GHz designs can be directly scaled to THz frequencies. We expect this promising technology to allow the construction of the first fully integrated THz heterodyne imaging arrays. At the University of Arizona, construction of the first laser micromachining system designed for THz waveguide components fabrication has been completed. Once tested and characterized our system will be used to construct prototype THz lx4 focal plane mixer arrays, magic tees, AR coated silicon lenses, local oscillator source phase gratings, filters and more. Our system can micro-machine structures down to a few microns accuracy and up to 6 inches across in a short time. This paper discusses the design and performance of our micromachining system, and illustrates the type, range and performance of components this exciting new technology will make accessible to the THz community.

  15. The PorX Response Regulator of the Porphyromonas gingivalis PorXY Two-Component System Does Not Directly Regulate the Type IX Secretion Genes but Binds the PorL Subunit

    PubMed Central

    Vincent, Maxence S.; Durand, Eric; Cascales, Eric

    2016-01-01

    The Type IX secretion system (T9SS) is a versatile multi-protein complex restricted to bacteria of the Bacteriodetes phylum and responsible for the secretion or cell surface exposition of diverse proteins that participate to S-layer formation, gliding motility or pathogenesis. The T9SS is poorly characterized but a number of proteins involved in the assembly of the secretion apparatus in the oral pathogen Porphyromonas gingivalis have been identified based on genome substractive analyses. Among these proteins, PorY, and PorX encode typical two-component system (TCS) sensor and CheY-like response regulator respectively. Although the porX and porY genes do not localize at the same genetic locus, it has been proposed that PorXY form a bona fide TCS. Deletion of porX in P. gingivalis causes a slight decrease of the expression of a number of other T9SS genes, including sov, porT, porP, porK, porL, porM, porN, and porY. Here, we show that PorX and the soluble cytoplasmic domain of PorY interact. Using electrophoretic mobility shift, DNA-protein co-purification and heterologous host expression assays, we demonstrate that PorX does not bind T9SS gene promoters and does not directly regulate expression of the T9SS genes. Finally, we show that PorX interacts with the cytoplasmic domain of PorL, a component of the T9SS membrane core complex and propose that the CheY-like PorX protein might be involved in the dynamics of the T9SS.

  16. Communication between Thiamin Cofactors in the Escherichia coli Pyruvate Dehydrogenase Complex E1 Component Active Centers EVIDENCE FOR A DIRECT PATHWAY BETWEEN THE 4′-AMINOPYRIMIDINE N1′ ATOMS

    SciTech Connect

    Nemeria, Natalia S; Arjunan, Palaniappa; Chandrasekhar, Krishnamoorthy; Mossad, Madouna; Tittmann, Kai; Furey, William; Jordan, Frank

    2010-11-03

    Kinetic, spectroscopic, and structural analysis tested the hypothesis that a chain of residues connecting the 4{prime}-aminopyrimidine N1{prime} atoms of thiamin diphosphates (ThDPs) in the two active centers of the Escherichia coli pyruvate dehydrogenase complex E1 component provides a signal transduction pathway. Substitution of the three acidic residues (Glu{sup 571}, Glu{sup 235}, and Glu{sup 237}) and Arg{sup 606} resulted in impaired binding of the second ThDP, once the first active center was filled, suggesting a pathway for communication between the two ThDPs. (1) Steady-state kinetic and fluorescence quenching studies revealed that upon E571A, E235A, E237A, and R606A substitutions, ThDP binding in the second active center was affected. (2) Analysis of the kinetics of thiazolium C2 hydrogen/deuterium exchange of enzyme-bound ThDP suggests half-of-the-sites reactivity for the E1 component, with fast (activated site) and slow exchanging sites (dormant site). The E235A and E571A variants gave no evidence for the slow exchanging site, indicating that only one of two active sites is filled with ThDP. (3) Titration of the E235A and E237A variants with methyl acetylphosphonate monitored by circular dichroism suggested that only half of the active sites were filled with a covalent predecarboxylation intermediate analog. (4) Crystal structures of E235A and E571A in complex with ThDP revealed the structural basis for the spectroscopic and kinetic observations and showed that either substitution affects cofactor binding, despite the fact that Glu{sup 235} makes no direct contact with the cofactor. The role of the conserved Glu{sup 571} residue in both catalysis and cofactor orientation is revealed by the combined results for the first time.

  17. NRPD4, a Protein Related to the RPB4 Subunit of RNA Polymerase II, is a Component of RNA Polymerases IV and V and is Required for RNA-directed DNA methylation

    SciTech Connect

    He, Xin-Jian; Hsu, Yi-Feng; Pontes, Olga; Zhu, Jianhua; Lu, Jian; Bressan, Ray A.; Pikaard, Craig S.; Wang, Co-Shine; Zhu, Jian-Kang

    2009-01-01

    RNA-directed DNA methylation (RdDM) is an RNAi-based mechanism for establishing transcriptional gene silencing in plants. The plant-specific RNA polymerases IV and V are required for the generation of 24-nucleotide (nt) siRNAs and for guiding sequence-specific DNA methylation by the siRNAs, respectively. However, unlike the extensively studied multisubunit Pol II, our current knowledge about Pol IV and Pol V is restricted to only the two largest subunits NRPD1a/NRPD1 and NRPD1b/NRPE1 and the one second-largest subunit NRPD2a. It is unclear whether other subunits may be required for the functioning of Pol IV and Pol V in RdDM. From a genetic screen for second-site suppressors of the DNA demethylase mutant ros1, we identified a new component (referred to as RDM2) as well as seven known components (NRPD1, NRPE1, NRPD2a, AGO4, HEN1, DRD1, and HDA6) of the RdDM pathway. The differential effects of the mutations on two mechanistically distinct transcriptional silencing reporters suggest that RDM2, NRPD1, NRPE1, NRPD2a, HEN1, and DRD1 function only in the siRNA-dependent pathway of transcriptional silencing, whereas HDA6 and AGO4 have roles in both siRNA-dependent and -independent pathways of transcriptional silencing. In the rdm2 mutants, DNA methylation and siRNA accumulation were reduced substantially at loci previously identified as endogenous targets of Pol IV and Pol V, including 5S rDNA, MEA-ISR, AtSN1, AtGP1, and AtMU1. The amino acid sequence of RDM2 is similar to that of RPB4 subunit of Pol II, but we show evidence that RDM2 has diverged significantly from RPB4 and cannot function in Pol II. An association of RDM2 with both NRPD1 and NRPE1 was observed by coimmunoprecipitation and coimmunolocalization assays. Our results show that RDM2/NRPD4/NRPE4 is a new component of the RdDM pathway in Arabidopsis and that it functions as part of Pol IV and Pol V.

  18. Quantitative planar laser-induced fluorescence imaging of multi-component fuel/air mixing in a firing gasoline-direct-injection engine: Effects of residual exhaust gas on quantitative PLIF

    SciTech Connect

    Williams, Ben; Ewart, Paul; Wang, Xiaowei; Stone, Richard; Ma, Hongrui; Walmsley, Harold; Cracknell, Roger; Stevens, Robert; Richardson, David; Fu, Huiyu; Wallace, Stan

    2010-10-15

    A study of in-cylinder fuel-air mixing distributions in a firing gasoline-direct-injection engine is reported using planar laser-induced fluorescence (PLIF) imaging. A multi-component fuel synthesised from three pairs of components chosen to simulate light, medium and heavy fractions was seeded with one of three tracers, each chosen to co-evaporate with and thus follow one of the fractions, in order to account for differential volatility of such components in typical gasoline fuels. In order to make quantitative measurements of fuel-air ratio from PLIF images, initial calibration was by recording PLIF images of homogeneous fuel-air mixtures under similar conditions of in-cylinder temperature and pressure using a re-circulation loop and a motored engine. This calibration method was found to be affected by two significant factors. Firstly, calibration was affected by variation of signal collection efficiency arising from build-up of absorbing deposits on the windows during firing cycles, which are not present under motored conditions. Secondly, the effects of residual exhaust gas present in the firing engine were not accounted for using a calibration loop with a motored engine. In order to account for these factors a novel method of PLIF calibration is presented whereby 'bookend' calibration measurements for each tracer separately are performed under firing conditions, utilising injection into a large upstream heated plenum to promote the formation of homogeneous in-cylinder mixtures. These calibration datasets contain sufficient information to not only characterise the quantum efficiency of each tracer during a typical engine cycle, but also monitor imaging efficiency, and, importantly, account for the impact of exhaust gas residuals (EGR). By use of this method EGR is identified as a significant factor in quantitative PLIF for fuel mixing diagnostics in firing engines. The effects of cyclic variation in fuel concentration on burn rate are analysed for different

  19. The β-propeller gene Rv1057 of Mycobacterium tuberculosis has a complex promoter directly regulated by both the MprAB and TrcRS two-component systems

    PubMed Central

    Pang, Xiuhua; Cao, Guangxiang; Neuenschwander, Pierre F.; Haydel, Shelley E.; Hou, Guihua; Howard, Susan T.

    2011-01-01

    SUMMARY The β-propeller gene Rv1057 of Mycobacterium tuberculosis is activated by envelope stress and was first characterized as a regulatory target of the TrcRS two-component system (TCS). Rv1057 expression is repressed by TrcRS, and the Rv1057 proximal promoter contains a TrcR binding site. In this study, we determined that Rv1057 is also directly regulated by MprAB, a TCS associated with envelope stress. Multiple potential MprA binding sites (MprA boxes) were identified in the 1 kb intergenic region upstream of Rv1057, and four sites were shown to bind MprA. Although MprA boxes were found in the proximal promoter, analyses suggest that MprA and TrcR do not compete for binding in this region. An MprAB-dependent, detergent-inducible transcriptional start point for Rv1057 was identified downstream of the MprA boxes, and a second TrcR binding site and small ORF of the 13E12 family were discovered in the distal promoter. MprAB was required for activation of Rv1057 during growth in macrophages and under detergent stress, and lacZ promoter constructs suggest the entire intergenic region is utilized during MprAB-dependent activation of Rv1057. These findings indicate that Rv1057 has an extensive and complex promoter, and provide evidence for coordinated regulation of stress response genes by TCSs. PMID:22099420

  20. Scientific Software Component Technology

    SciTech Connect

    Kohn, S.; Dykman, N.; Kumfert, G.; Smolinski, B.

    2000-02-16

    parallel components. While industrial component systems do not directly address scientific computing issues, we leverage existing industry technologies and design concepts whenever possible.

  1. Sequential ranging: How it works

    NASA Technical Reports Server (NTRS)

    Baugh, Harold W.

    1993-01-01

    This publication is directed to the users of data from the Sequential Ranging Assembly (SRA), and to others who have a general interest in range measurements. It covers the hardware, the software, and the processes used in acquiring range data; it does not cover analytical aspects such as the theory of modulation, detection, noise spectral density, and other highly technical subjects. In other words, it covers how ranging is done, but not the details of why it works. The publication also includes an appendix that gives a brief discussion of PN ranging, a capability now under development.

  2. Definition of Contravariant Velocity Components

    NASA Technical Reports Server (NTRS)

    Hung, Ching-moa; Kwak, Dochan (Technical Monitor)

    2002-01-01

    In this paper we have reviewed the basics of tensor analysis in an attempt to clarify some misconceptions regarding contravariant and covariant vector components as used in fluid dynamics. We have indicated that contravariant components are components of a given vector expressed as a unique combination of the covariant base vector system and, vice versa, that the covariant components are components of a vector expressed with the contravariant base vector system. Mathematically, expressing a vector with a combination of base vector is a decomposition process for a specific base vector system. Hence, the contravariant velocity components are decomposed components of velocity vector along the directions of coordinate lines, with respect to the covariant base vector system. However, the contravariant (and covariant) components are not physical quantities. Their magnitudes and dimensions are controlled by their corresponding covariant (and contravariant) base vectors.

  3. Components of Successful Magnet Schools.

    ERIC Educational Resources Information Center

    Bryant, Faye B.

    This paper identifies and discusses components of successful magnet programs. It is based on a review of existing research literature and information gathered directly from school districts. First, the paper discusses separately the following elements, which are considered "core components": (1) leadership; (2) organizational structure; (3)…

  4. Range Process Simulation Tool

    NASA Technical Reports Server (NTRS)

    Phillips, Dave; Haas, William; Barth, Tim; Benjamin, Perakath; Graul, Michael; Bagatourova, Olga

    2005-01-01

    Range Process Simulation Tool (RPST) is a computer program that assists managers in rapidly predicting and quantitatively assessing the operational effects of proposed technological additions to, and/or upgrades of, complex facilities and engineering systems such as the Eastern Test Range. Originally designed for application to space transportation systems, RPST is also suitable for assessing effects of proposed changes in industrial facilities and large organizations. RPST follows a model-based approach that includes finite-capacity schedule analysis and discrete-event process simulation. A component-based, scalable, open architecture makes RPST easily and rapidly tailorable for diverse applications. Specific RPST functions include: (1) definition of analysis objectives and performance metrics; (2) selection of process templates from a processtemplate library; (3) configuration of process models for detailed simulation and schedule analysis; (4) design of operations- analysis experiments; (5) schedule and simulation-based process analysis; and (6) optimization of performance by use of genetic algorithms and simulated annealing. The main benefits afforded by RPST are provision of information that can be used to reduce costs of operation and maintenance, and the capability for affordable, accurate, and reliable prediction and exploration of the consequences of many alternative proposed decisions.

  5. The lunar laser ranging experiment.

    NASA Technical Reports Server (NTRS)

    Bender, P. L.; Currie, D. G.; Poultney, S. K.; Dicke, R. H.; Eckhardt, D. H.; Kaula, W. M.; Mulholland, J. D.; Plotkin, H. H.; Silverberg, E. C.; Faller, J. E.

    1973-01-01

    The scientific objectives achievable through high-accuracy range measurements to lunar retroreflectors are considered. A specific study of design questions related to the operation of retroreflectors on the lunar surface indicated that a reflector panel containing a number of solid fused silica corner reflectors would be capable of maintaining essentially diffraction limited performance under direct solar illumination. Initial Apollo 11 observations are discussed together with the installation of additional lunar retroreflectors in connection with the Luna 17, Apollo 14, Apollo 15, and Luna 21 missions. Range measurements at the McDonald Observatory are considered along with new results from lunar range data, and prospects regarding future lunar ranging stations.

  6. Apparatus for remotely handling components

    DOEpatents

    Szkrybalo, Gregory A.; Griffin, Donald L.

    1994-01-01

    The inventive apparatus for remotely handling bar-like components which define a longitudinal direction includes a gripper mechanism for gripping the component including first and second gripper members longitudinally fixedly spaced from each other and oriented parallel to each other in planes transverse to the longitudinal direction. Each gripper member includes a jaw having at least one V-groove with opposing surfaces intersecting at a base and extending radially relative to the longitudinal direction for receiving the component in an open end between the opposing surfaces. The V-grooves on the jaw plate of the first and second gripper members are aligned in the longitudinal direction to support the component in the first and second gripper members. A jaw is rotatably mounted on and a part of each of the first and second gripper members for selectively assuming a retracted mode in which the open end of the V-groove is unobstructed and active mode in which the jaw spans the open end of the V-groove in the first and second gripper members. The jaw has a locking surface for contacting the component in the active mode to secure the component between the locking surface of the jaw and the opposing surfaces of the V-groove. The locking surface has a plurality of stepped portions, each defining a progressively decreasing radial distance between the base of the V-groove and the stepped portion opposing the base to accommodate varying sizes of components.

  7. The development of direct write technology in BAE Systems

    NASA Astrophysics Data System (ADS)

    Sidhu, J.; McDonald, J.; Morgan, S.; Wescott, Andrew; O'Driscoll, E. J.

    2006-12-01

    Direct Write (DW) is an emerging group of technologies that allow printing of electronic and other functional components out of vacuum, directly onto structural parts and assemblies. With its ability to deposit a wide range of dissimilar materials, and transfer details directly from CAD/CAM, the process is very flexible, enabling rapid progress from design to fabrication. This paper provides an introduction to direct write, and describes the BAE Systems activities in this field. The paper also describes the use of lasers in direct write, and some provisional results on laser curing are presented.

  8. Laser generating metallic components

    NASA Astrophysics Data System (ADS)

    McLean, Marc A.; Shannon, G. J.; Steen, William M.

    1997-04-01

    Recent developments in rapid prototyping have led to the concept of laser generating, the first additive manufacturing technology. This paper presents an innovative process of depositing multi-layer tracks, by fusing successive powder tracks, to generate three dimensional components, thereby offering an alternative to casting for small metal component manufacture. A coaxial nozzle assembly has been designed and manufactured enabling consistent omni-directional multi-layer deposition. In conjunction with this the software route from a CAD drawing to machine code generation has been established. The part is manufactured on a six axes machining center incorporating a 1.8 kW carbon-dioxide laser, providing an integrated opto-mechanical workstation. The part build-up program is controlled by a P150 host computer, linked directly to the DNC machining center. The direct manufacturing route is shown, including initial examples of simple objects (primitives -- cube, cylinder, cone) leading to more complex turbine blade generation, incorporating build-up techniques and the associated mechanical properties.

  9. Intentionally Short Range Communications (ISRC)

    NASA Astrophysics Data System (ADS)

    Yen, J.; Poirier, P.; Obrien, M. E.; Gibeson, L.

    1993-05-01

    This document details the feasibility studies conducted for the Intentionally Short Range Communications (ISRC) project. The short-range limitation arises from the need for low probability of intercept (LPI), low probability of detection (LPD) communication links. The detection of an undecipherable transmission would still provide an enemy with information regarding transmitter location. The technologies being studied are ultraviolet (UV) lamps, UV lasers, infrared (IR) lasers, millimeter waves (MMW), and direct sequence spread spectrum.

  10. Laser fabrication of various polymer microoptical components

    NASA Astrophysics Data System (ADS)

    Malinauskas, M.; Žukauskas, A.; Belazaras, K.; Tikuišis, K.; Purlys, V.; Gadonas, R.; Piskarskas, A.

    2012-05-01

    In this report we present micro/nanostructuring of novel metal isopropoxides-silica containing hybrid sol-gel materials by the femtosecond laser direct writing technique and apply it for the fabrication of various microoptical/nanophotonic components. This approach enables one to photostructure true three-dimensional objects with controlled sub-100 nm spatial definition. Due to self-smoothing effects, surface roughness can be formed below 30 nm making this technique widely applicable for microoptical/nanophotonics devices in visible and near-infra-red wavelengths. After photopolymerization, these materials inherit desired optical properties: high transmittance in the 400-1500 nm spectral range and nearly glass-matching optical refractive index. Doping with organic dyes or quantum dots offers additional functionalities. Fields of applications cover: light guiding, coupling/extraction, trapping, signal processing and transferring, microscopy, biology, etc. In brief, we investigated direct laser writing structurability of these materials and its optimization for manufacturing microoptical/nanophotonic components. We successfully produced microoptical components such as aspheric and Fresnel lenses. We demonstrate the flexibility and reproducibility of this approach to fabricate custom-shaped elements on the tip of the optical fiber, thus producing integrated microoptical devices. The micro/nanostructures were characterized by optical and scanning electron microscopies, and optical profilometry. Their optical functions were measured using a custom-built setup to serve the purpose. The obtained values were in close coincidence to the theoretical values. Further research in the direction of production integrated and multifunctional components to be applied in the fields of photonics, plasmonics and telecommunications as well as optofluidics is currently being carried out.

  11. Revealing Optical Components

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The Optical Vector Analyzer (OVA) 1550 significantly reduces the time and cost of testing sophisticated optical components. The technology grew from the research Luna Technologies' Dr. Mark Froggatt conducted on optical fiber strain measurement while working at Langley Research Center. Dr. Froggatt originally developed the technology for non- destructive evaluation testing at Langley. The new technique can provide 10,000 independent strain measurements while adding less than 10 grams to the weight of the vehicle. The OVA is capable of complete linear characterization of single-mode optical components used in high- bit-rate applications. The device can test most components over their full range in less than 30 seconds, compared to the more than 20 minutes required by other testing methods. The dramatically shortened measurement time results in increased efficiency in final acceptance tests of optical devices, and the comprehensive data produced by the instrument adds considerable value for component consumers. The device eliminates manufacturing bottlenecks, while reducing labor costs and wasted materials during production.

  12. Giving Directions: A Teaching Art

    ERIC Educational Resources Information Center

    Flynn, Rosalind M.

    2007-01-01

    Engaging students productively in even the most thoroughly planned and richly meaningful arts activity requires giving effective directions. Giving effective directions, however, is a crucial art for teaching artists to master. In this article, the author discusses the components of giving directions. These components are: Tell students; Show…

  13. Directional acoustic measurements by laser Doppler velocimeters

    NASA Technical Reports Server (NTRS)

    Mazumder, M. K.; Overbey, R. L.; Testerman, M. K.

    1976-01-01

    Laser Doppler velocimeters (LDVs) are used as velocity microphones to measure sound pressure level in the range from 90 to 130 dB, spectral components, and two-point correlation functions for acoustic-noise source identification. Close agreement between LDV and microphone data is observed. Directional sensitivity and the ability to measure remotely make LDVs useful tools for acoustic measurement where placement of any physical probe is difficult or undesirable, as in the diagnosis of jet noise.

  14. Refrigerant directly cooled capacitors

    DOEpatents

    Hsu, John S.; Seiber, Larry E.; Marlino, Laura D.; Ayers, Curtis W.

    2007-09-11

    The invention is a direct contact refrigerant cooling system using a refrigerant floating loop having a refrigerant and refrigeration devices. The cooling system has at least one hermetic container disposed in the refrigerant floating loop. The hermetic container has at least one electronic component selected from the group consisting of capacitors, power electronic switches and gating signal module. The refrigerant is in direct contact with the electronic component.

  15. Determination of corrections to flow direction sensor measurements over an angle-of-attack range from 0 degree to 85 degrees. M.S. Thesis - George Washington Univ., August 1983

    NASA Technical Reports Server (NTRS)

    Moul, T. M.

    1985-01-01

    An investigation was conducted into the nature of corrections for angle-of-attack and angle-of-sideslip measurements obtained with sensors mounted in front of each wingtip of a general aviation airplane. These flow corrections have been obtained from both wind-tunnel and flight tests over an angle-of-attack range from 0 to 85 deg. Both the angle-of-attack and angle-of-sideslip flow corrections were found to be substantial. The corrections were a function of the angle of attack and angle of sideslip and were fairly insensitive to configuration changes and rotational effects. The angle-of-attack flow correction determined from the static wind-tunnel tests agreed reasonably well with the correction determined from flight tests.

  16. Range determination for scannerless imaging

    DOEpatents

    Muguira, Maritza Rosa; Sackos, John Theodore; Bradley, Bart Davis; Nellums, Robert

    2000-01-01

    A new method of operating a scannerless range imaging system (e.g., a scannerless laser radar) has been developed. This method is designed to compensate for nonlinear effects which appear in many real-world components. The system operates by determining the phase shift of the laser modulation, which is a physical quantity related physically to the path length between the laser source and the detector, for each pixel of an image.

  17. Airframe noise component interaction studies

    NASA Technical Reports Server (NTRS)

    Fink, M. R.; Schlinker, R. H.

    1979-01-01

    Acoustic wind tunnel tests were conducted of a two-dimensional wing section with removable high-lift leading and trailing edge devices and a removeable two-wheel landing gear with open cavity. An array of far field conventional microphones and an acoustic mirror directional microphone were utilized to determine far field spectrum levels and noise source distribution. Data were obtained for the wing with components deployed separately and in various combinations. The basic wing model had 0.305 m (1.00 ft) chord, which is roughly 1/10 scale for a one-hundred passenger transport airplane. Most of the data were obtained at 70.7 and 100 m/sec (232 and 328 ft/sec) airspeeds, which bracket the range of practical approach speeds for such aircraft. Data were obtained at frequence to 40 kHz so that, when scaled to s typical full-airframe, the frequency region which strongly influences preceived noise level would be included.

  18. Direct Aerosol Forcing Uncertainty

    DOE Data Explorer

    Mccomiskey, Allison

    2008-01-15

    Understanding sources of uncertainty in aerosol direct radiative forcing (DRF), the difference in a given radiative flux component with and without aerosol, is essential to quantifying changes in Earth's radiation budget. We examine the uncertainty in DRF due to measurement uncertainty in the quantities on which it depends: aerosol optical depth, single scattering albedo, asymmetry parameter, solar geometry, and surface albedo. Direct radiative forcing at the top of the atmosphere and at the surface as well as sensitivities, the changes in DRF in response to unit changes in individual aerosol or surface properties, are calculated at three locations representing distinct aerosol types and radiative environments. The uncertainty in DRF associated with a given property is computed as the product of the sensitivity and typical measurement uncertainty in the respective aerosol or surface property. Sensitivity and uncertainty values permit estimation of total uncertainty in calculated DRF and identification of properties that most limit accuracy in estimating forcing. Total uncertainties in modeled local diurnally averaged forcing range from 0.2 to 1.3 W m-2 (42 to 20%) depending on location (from tropical to polar sites), solar zenith angle, surface reflectance, aerosol type, and aerosol optical depth. The largest contributor to total uncertainty in DRF is usually single scattering albedo; however decreasing measurement uncertainties for any property would increase accuracy in DRF. Comparison of two radiative transfer models suggests the contribution of modeling error is small compared to the total uncertainty although comparable to uncertainty arising from some individual properties.

  19. Miniature probes for use in gas turbine testing. [component reliability measuring instruments

    NASA Technical Reports Server (NTRS)

    Glawe, G. E.; Krause, L. N.

    1974-01-01

    Several examples of miniature probes (null type as well as fixed position) are presented which have proved useful in aircraft and space power systems component testing and are applicable to automotive gas turbine testing. These probes are used to determine component or system performance from the measurement of gas temperature as well as total and static pressure, and flow direction. Detailed drawings of the sensors are presented along with experimental data covering the flow characteristics over the range of intended use.

  20. Analysis of three-component aeromagnetic data. [over total field measurements

    NASA Technical Reports Server (NTRS)

    Bhattacharyya, B. K.; Leu, L. K.

    1973-01-01

    The numerical method of obtaining three field components from total field measurements, using double Fourier series expansion, is presented. The expressions for moments of the anomalous field components over a finite area are given. The magnitude and direction of the magnetization vector indicate that the vertical component of the magnetic field calculated from total field observations is more accurate at higher geomagnetic latitudes than at lower latitudes. The opposite is true for the horizontal components. The error in determining the magnetization vector directions are significantly large over most of the range of variation of declination and inclination of the vector, demonstrating the practical limitations of computing field components from total field data even under the best of conditions.

  1. Variances of Cylinder Parameters Fitted to Range Data

    PubMed Central

    Franaszek, Marek

    2012-01-01

    Industrial pipelines are frequently scanned with 3D imaging systems (e.g., LADAR) and cylinders are fitted to the collected data. Then, the fitted as-built model is compared with the as-designed model. Meaningful comparison between the two models requires estimates of uncertainties of fitted model parameters. In this paper, the formulas for variances of cylinder parameters fitted with Nonlinear Least Squares to a point cloud acquired from one scanning position are derived. Two different error functions used in minimization are discussed: the orthogonal and the directional function. Derived formulas explain how some uncertainty components are propagated from measured ranges to fitted cylinder parameters. PMID:26900527

  2. Telemetry Ranging: Concepts

    NASA Astrophysics Data System (ADS)

    Hamkins, J.; Kinman, P.; Xie, H.; Vilnrotter, V.; Dolinar, S.

    2015-11-01

    Telemetry ranging is a proposed alternative to conventional two-way ranging for determining the two-way time delay between a Deep Space Station (DSS) and a spacecraft. The advantage of telemetry ranging is that the ranging signal on the uplink is not echoed to the downlink, so that telemetry alone modulates the downlink carrier. The timing information needed on the downlink, in order to determine the two-way time delay, is obtained from telemetry frames. This article describes the phase and timing estimates required for telemetry ranging, and how two-way range is calculated from these estimates. It explains why the telemetry ranging architecture does not require the spacecraft transponder to have a high-frequency or high-quality oscillator, and it describes how a telemetry ranging system can be infused in the Deep Space Network.

  3. Limited range of motion

    MedlinePlus

    Limited range of motion is a term meaning that a joint or body part cannot move through its normal range of motion. ... Motion may be limited because of a problem within the joint, swelling of tissue around the joint, ...

  4. SAR ambiguous range suppression.

    SciTech Connect

    Doerry, Armin Walter

    2006-09-01

    Pulsed Radar systems suffer range ambiguities, that is, echoes from pulses transmitted at different times arrive at the receiver simultaneously. Conventional mitigation techniques are not always adequate. However, pulse modulation schemes exist that allow separation of ambiguous ranges in Doppler space, allowing easy filtering of problematic ambiguous ranges.

  5. RADIO RANGING DEVICE

    DOEpatents

    Nieset, R.T.

    1961-05-16

    A radio ranging device is described. It utilizes a super regenerative detector-oscillator in which echoes of transmitted pulses are received in proper phase to reduce noise energy at a selected range and also at multiples of the selected range.

  6. Long Range Technology Planning.

    ERIC Educational Resources Information Center

    Ambron, Sueann, Ed.

    1986-01-01

    This summary of a meeting of the Apple Education Advisory Council, on long range technology plans at the state, county, district, and school levels, includes highlights from group discussions on future planning, staff development, and curriculum. Three long range technology plans at the state level are provided: Long Range Educational Technology…

  7. The Coordination of Components for Educational Building.

    ERIC Educational Resources Information Center

    Department of Education and Science, London (England).

    The coordination of the building components of educational facilities is discussed. The resulting components will be used for a wide range of building types in addition to schools and the recommendation should therefore be seen as part of a widespread move toward establishing a national British 'pool' of dimensionally related components. The two…

  8. Object silhouettes and surface directions through stereo matching image processing

    NASA Astrophysics Data System (ADS)

    Akiyama, Akira; Kumagai, Hideo

    2015-09-01

    We have studied the object silhouettes and surface direction through the stereo matching image processing to recognize the position, size and surface direction of the object. For this study we construct the pixel number change distribution of the HSI color component level, the binary component level image by the standard deviation threshold, the 4 directional pixels connectivity filter, the surface elements correspondence by the stereo matching and the projection rule relation. We note that the HSI color component level change tendency of the object image near the focus position is more stable than the HSI color component level change tendency of the object image over the unfocused range. We use the HSI color component level images near the fine focused position to extract the object silhouette. We extract the object silhouette properly. We find the surface direction of the object by the pixel numbers of the correspondence surface areas and the projection cosine rule after the stereo matching image processing by the characteristic areas and the synthesized colors. The epipolar geometry is used in this study because a pair of imager is arranged on the same epipolar plane. The surface direction detection results in the proper angle calculation. The construction of the object silhouettes and the surface direction detection of the object are realized.

  9. Polymeric components for telecom and datacom

    NASA Astrophysics Data System (ADS)

    Diemeer, Mart; Dekker, Ronald; Hilderink, Lucie; Leinse, Arne; Balakrishnan, Muralidharan; Faccini, Mirko; Driessen, Alfred

    2005-09-01

    Polymeric optical waveguide components offer attractive properties for applications in optical telecom and datacom systems. These are high speed for electro-optic modulators, low power dissipation for thermo-optic (digital) switches and low-cost for all active and passive components. We report on active and passive components realized by utilizing polymer-specific attractive techniques such as planarizing spincoating, low-temperature reflowing and direct photodefinition. Examples are multimode photodefined passive polymeric waveguides for optical interconnect applications; photodefined monomode polymeric waveguides loaded with rare-earth doped nanoparticles for planar waveguide amplifiers and with non-linear chromophores for electro-optic modulators. We will show that polymer waveguide technology allows vertical stacking of electro-optic microringresonators with their port waveguides to realize high-speed modulators. By reflowing the reactive-ion-etched microring we could reduce the scattering by wall roughness considerably. Thermo-optic polymeric microringresonators combine the high thermo-optic coefficient and low thermal conductivity of polymers with the small size of the microring. It will be shown that this yields a broad wavelength tuning range at low power dissipation.

  10. Principal component analysis for designed experiments

    PubMed Central

    2015-01-01

    Background Principal component analysis is used to summarize matrix data, such as found in transcriptome, proteome or metabolome and medical examinations, into fewer dimensions by fitting the matrix to orthogonal axes. Although this methodology is frequently used in multivariate analyses, it has disadvantages when applied to experimental data. First, the identified principal components have poor generality; since the size and directions of the components are dependent on the particular data set, the components are valid only within the data set. Second, the method is sensitive to experimental noise and bias between sample groups. It cannot reflect the experimental design that is planned to manage the noise and bias; rather, it estimates the same weight and independence to all the samples in the matrix. Third, the resulting components are often difficult to interpret. To address these issues, several options were introduced to the methodology. First, the principal axes were identified using training data sets and shared across experiments. These training data reflect the design of experiments, and their preparation allows noise to be reduced and group bias to be removed. Second, the center of the rotation was determined in accordance with the experimental design. Third, the resulting components were scaled to unify their size unit. Results The effects of these options were observed in microarray experiments, and showed an improvement in the separation of groups and robustness to noise. The range of scaled scores was unaffected by the number of items. Additionally, unknown samples were appropriately classified using pre-arranged axes. Furthermore, these axes well reflected the characteristics of groups in the experiments. As was observed, the scaling of the components and sharing of axes enabled comparisons of the components beyond experiments. The use of training data reduced the effects of noise and bias in the data, facilitating the physical interpretation of the

  11. Telemetry Ranging: Signal Processing

    NASA Astrophysics Data System (ADS)

    Hamkins, J.; Kinman, P.; Xie, H.; Vilnrotter, V.; Dolinar, S.

    2016-02-01

    This article describes the details of the signal processing used in a telemetry ranging system in which timing information is extracted from the downlink telemetry signal in order to compute spacecraft range. A previous article describes telemetry ranging concepts and architecture, which are a slight variation of a scheme published earlier. As in that earlier work, the telemetry ranging concept eliminates the need for a dedicated downlink ranging signal to communicate the necessary timing information. The present article describes the operation and performance of the major receiver functions on the spacecraft and the ground --- many of which are standard tracking loops already in use in JPL's flight and ground radios --- and how they can be used to provide the relevant information for making a range measurement. It also describes the implementation of these functions in software, and performance of an end-to-end software simulation of the telemetry ranging system.

  12. Txc, a new type II secretion system of Pseudomonas aeruginosa strain PA7, is regulated by the TtsS/TtsR two-component system and directs specific secretion of the CbpE chitin-binding protein.

    PubMed

    Cadoret, Frédéric; Ball, Geneviève; Douzi, Badreddine; Voulhoux, Romé

    2014-07-01

    We present here the functional characterization of a third complete type II secretion system (T2SS) found in newly sequenced Pseudomonas aeruginosa strain PA7. We call this system Txc (third Xcp homolog). This system is encoded by the RGP69 region of genome plasticity found uniquely in strain PA7. In addition to the 11 txc genes, RGP69 contains two additional genes encoding a possible T2SS substrate and a predicted unorthodox sensor protein, TtsS (type II secretion sensor). We also identified a gene encoding a two-component response regulator called TtsR (type II secretion regulator), which is located upstream of the ttsS gene and just outside RGP69. We show that TtsS and TtsR constitute a new and functional two-component system that controls the production and secretion of the RGP69-encoded T2SS substrate in a Txc-dependent manner. Finally, we demonstrate that this Txc-secreted substrate binds chitin, and we therefore name it CbpE (chitin-binding protein E). PMID:24748613

  13. Txc, a New Type II Secretion System of Pseudomonas aeruginosa Strain PA7, Is Regulated by the TtsS/TtsR Two-Component System and Directs Specific Secretion of the CbpE Chitin-Binding Protein

    PubMed Central

    Cadoret, Frédéric; Ball, Geneviève; Douzi, Badreddine

    2014-01-01

    We present here the functional characterization of a third complete type II secretion system (T2SS) found in newly sequenced Pseudomonas aeruginosa strain PA7. We call this system Txc (third Xcp homolog). This system is encoded by the RGP69 region of genome plasticity found uniquely in strain PA7. In addition to the 11 txc genes, RGP69 contains two additional genes encoding a possible T2SS substrate and a predicted unorthodox sensor protein, TtsS (type II secretion sensor). We also identified a gene encoding a two-component response regulator called TtsR (type II secretion regulator), which is located upstream of the ttsS gene and just outside RGP69. We show that TtsS and TtsR constitute a new and functional two-component system that controls the production and secretion of the RGP69-encoded T2SS substrate in a Txc-dependent manner. Finally, we demonstrate that this Txc-secreted substrate binds chitin, and we therefore name it CbpE (chitin-binding protein E). PMID:24748613

  14. Hyaluronan: A Matrix Component

    NASA Astrophysics Data System (ADS)

    Rügheimer, Louise

    2008-09-01

    The glucosaminoglycan hyaluronan is a key component of the extracellular matrix. It is a large, negatively charged molecule that can act as an ion exchange reservoir for positive ions. Hyaluronan is involved in renomedullary water handling through its water-binding capacity. In the renal medulla, the main source for hyaluronan production is the renomedullary interstitial cells. Hyaluronan synthases are found in the inner part of the plasma membrane and polymerize hyaluronan chains which are extruded into the extracellular space. Hyaluronidases are a family of enzymes involved in the degradation of hyaluronan. They have a wide range of properties, including differences in size, inhibitor sensitivities, catalytic mechanisms, substrate specificities and pH optima.

  15. The Geoscience Laser Altimetry/Ranging System

    NASA Technical Reports Server (NTRS)

    Cohen, Steven C.; Degnan, John J., III; Bufton, Jack L.; Garvin, James B.; Abshire, James B.

    1987-01-01

    The Geoscience Laser Altimetry/Ranging System (GLARS), a combined laser ranging and altimetry system capable of subcentimeter position determinations of retroflector targets and subdecimeter profiling of topography, is described. The system uses advanced but currently available state-of-the-art components. Laboratory, field, and numerical experiments have indicated the suitability of GLARS as an instrument for Eos and other space platforms.

  16. Airframe noise component interaction studies

    NASA Technical Reports Server (NTRS)

    Fink, M. R.; Schlinker, R. H.

    1979-01-01

    Acoustic wind tunnel tests were conducted to examine the noise-generating processes of an airframe during approach flight. The airframe model was a two-dimensional wing section, to which highlift leading and trailing edge devices and landing gear could be added. Far field conventional microphones were utilized to determine component spectrum levels. An acoustic mirror directional microphone was utilized to examine noise source distributions on airframe components extended separately and in combination. Measured quantities are compared with predictions inferred from aircraft flyover data. Aeroacoustic mechanisms for each airframe component are identified. Component interaction effects on total radiated noise generally were small (within about 2 dB). However, some interactions significantly redistributed the local noise source strengths by changing local flow velocities and turbulence levels. Possibilities for noise reduction exist if trailing edge flaps could be modified to decrease their noise radiation caused by incident turbulent flow.

  17. Future direction of direct writing

    NASA Astrophysics Data System (ADS)

    Kim, Nam-Soo; Han, Kenneth N.

    2010-11-01

    Direct write technology using special inks consisting of finely dispersed metal nanoparticles in liquid is receiving an undivided attention in recent years for its wide range of applicability in modern electronic industry. The application of this technology covers radio frequency identification-tag (RFID-tag), flexible-electronics, organic light emitting diodes (OLED) display, e-paper, antenna, bumpers used in flip-chip, underfilling, frit, miniresistance applications and biological uses, artificial dental applications and many more. In this paper, the authors have reviewed various direct write technologies on the market and discussed their advantages and shortfalls. Emphasis has given on microdispensing deposition write (MDDW), maskless mesoscale materials deposition (M3D), and ink-jet technologies. All of these technologies allow printing various patterns without employing a mask or a resist with an enhanced speed with the aid of computer. MDDW and M3D are capable of drawing patterns in three-dimension and MDDW, in particular, is capable of writing nanoinks with high viscosity. However, it is still far away for direct write to be fully implemented in the commercial arena. One of the hurdles to overcome is in manufacturing conductive inks which are chemically and physically stable, capable of drawing patterns with acceptable conductivity, and also capable of drawing patterns with acceptable adhesiveness with the substrates. The authors have briefly discussed problems involved in manufacturing nanometal inks to be used in various writing devices. There are numerous factors to be considered in manufacturing such inks. They are reducing agents, concentrations, oxidation, compact ability allowing good conductivity, and stability in suspension.

  18. Range Scheduling Aid (RSA)

    NASA Technical Reports Server (NTRS)

    Logan, J. R.; Pulvermacher, M. K.

    1991-01-01

    Range Scheduling Aid (RSA) is presented in the form of the viewgraphs. The following subject areas are covered: satellite control network; current and new approaches to range scheduling; MITRE tasking; RSA features; RSA display; constraint based analytic capability; RSA architecture; and RSA benefits.

  19. Laser ranging data analysis

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Near real-time Lageos laser ranging data are analyzed in terms of range bias, time bias, and internal precision, and estimates for earth orientation parameters X(sub p), Y(sub p), and UT1 are obtained. The results of these analyses are reported in a variety of formats. Copies of monthly summaries from November, 1986 through November, 1987 are included.

  20. Estimating unbiased horizontal velocity components from ST/MST radar measurements: A case study

    NASA Technical Reports Server (NTRS)

    Clark, W. L.; Green, J. L.; Warnock, J. M.

    1983-01-01

    In this paper a self-editing quick look procedure is presented for use at the Sunset radar. It is used for determining relatively unbiased hourly estimates of the u and v components of the wind. The technique presented here should be applicable to all height ranges, though only ST results are presented here. The vertical wind component, w, may be measured directly by pointing the radar beam straight up. The east and west components of the wind, u and v, however, must be estimated by projecting to the horizontal plane the radial velocity, vr, actually observed by pointing the radar suitably off zenith.

  1. Long range fast tool servo

    NASA Astrophysics Data System (ADS)

    Moorefield, G. M., II; Dow, Thomas A.; Falter, Karl J.; Ro, Paul I.

    1993-05-01

    The PEC's MAC 100 Fast Tool Servo (FTS) System has demonstrated the efficacy of fabricating off-axis parabolic segments on axis by utilizing a fast tool motion to machine non-rotationally symmetric surfaces. The key to this technique was a servo for the tool motion that had a high-bandwidth coupled with a small range of motion. The Keck telescope, with its thirty-six (36) 1-meter diameter segments, would have been an excellent application for this technology. Since this technology was not available at the time of construction, each mirror segment was fabricated to its desired shape by loading it to a specified deformed shape and polishing it to a spherical contour, then removing the bending loads to allow the segment to relax to the desired asymmetric shape. If the segments of this optic had been constructed on axis with an FTS, the fabrication of the most extreme segment would have required only about 200 micrometers of non-rotational symmetry. However, the demand for larger displacement actuators is being driven by new applications with nonrotationally symmetric components in the millimeter range. This report describes the search for a suitable actuator for a long range fast tool servo system that would allow the fabrication of non-rotationally symmetric optical surfaces with a 1 mm range of servo motion. To allow cost-effective machining of these surfaces, the actuator must also possess a 50 Hz bandwidth (minimum) and 25 nanometer resolution.

  2. Miniature large range multi-axis force-torque sensor for biomechanical applications

    NASA Astrophysics Data System (ADS)

    Brookhuis, R. A.; Sanders, R. G. P.; Ma, K.; Lammerink, T. S. J.; de Boer, M. J.; Krijnen, G. J. M.; Wiegerink, R. J.

    2015-02-01

    A miniature force sensor for the measurement of forces and moments at a human fingertip is designed and realized. Thin silicon pillars inside the sensor provide in-plane guidance for shear force measurement and provide the spring constant in normal direction. A corrugated silicon ring around the force sensitive area provides the spring constant in shear direction and seals the interior of the sensor. To detect all load components, capacitive read-out is used. A novel electrode pattern results in a large shear force sensitivity. The fingertip force sensor has a wide force range of up to 60 N in normal direction, ± 30 N in shear direction and a torque range of ± 25 N mm.

  3. Fast analysis using monolithic columns coupled with high-flow on-line extraction and electrospray mass spectrometric detection for the direct and simultaneous quantitation of multiple components in plasma.

    PubMed

    Zeng, Hang; Deng, Yuzhong; Wu, Jing-Tao

    2003-05-25

    In this work, monolithic columns were used as a fast separation tool for multiple-component quantitative liquid chromatography-tandem mass spectrometry (LC-MS-MS) assays of drug candidates in biological fluids. A considerably reduced runtime was achieved while maintaining good chromatographic separations. This significantly improved separation speed demanded higher throughput on sample extraction. To this end, monolithic separations were coupled on-line with high-flow extraction, which allowed for the fast extraction and separation of samples containing multiple analytes. An evaluation of this system was performed using a mixture of fenfluramine, temazepam, oxazepam, and tamoxifen in plasma. A total cycle time of 1.2 min was achieved which included both sample extraction and subsequent monolithic column separation via column switching. A total of over 400 plasma samples were analyzed in less than 10 h. The sensitivity and responses were reproducible throughout the run. The system has been routinely used in the authors' laboratory for high-throughput quantitation of compounds in biological fluids in support of drug discovery programs. The assay for samples from a 9-in-1 dog pharmacokinetic study is shown as an example to demonstrate the capability of this system. PMID:12705973

  4. Explosive components facility certification tests

    SciTech Connect

    Dorrell, L.; Johnson, D.

    1995-08-01

    Sandia National Laboratories has recently completed construction of a new Explosive Components Facility (ECF) that will be used for the research and development of advanced explosives technology. The ECF includes nine indoor firing pads for detonating explosives and monitoring the detonations. Department of Energy requirements for certification of this facility include detonation of explosive levels up to 125 percent of the rated firing pad capacity with no visual structural degradation resulting from the explosion. The Explosives Projects and Diagnostics Department at Sandia decided to expand this certification process to include vibration and acoustic monitoring at various locations throughout the building during these explosive events. This information could then be used to help determine the best locations for noise and vibration sensitive equipment (e.g. scanning electron microscopes) used for analysis throughout the building. This facility has many unique isolation features built into the explosive chamber and laboratory areas of the building that allow normal operation of other building activities during explosive tests. This paper discusses the design of this facility and the various types of explosive testing performed by the Explosives Projects and Diagnostics Department at Sandia. However, the primary focus of the paper is directed at the vibration and acoustic data acquired during the certification process. This includes the vibration test setup and data acquisition parameters, as well as analysis methods used for generating peak acceleration levels and spectral information. Concerns over instrumentation issues such as the choice of transducers (appropriate ranges, resonant frequencies, etc.) and measurements with long cable lengths (500 feet) are also discussed.

  5. Photoresistance analog multiplier has wide range

    NASA Technical Reports Server (NTRS)

    Hartenstein, R. G.

    1965-01-01

    Photoactivated bridge facilitates equal performance of analog multipliers over a wide frequency range. The multiplier operates from direct current to an upper frequency limited by either the light source or the closed-loop amplifier.

  6. Isolation and characterization of selective and potent human Fab inhibitors directed to the active-site region of the two-component NS2B-NS3 proteinase of West Nile virus.

    PubMed

    Shiryaev, Sergey A; Radichev, Ilian A; Ratnikov, Boris I; Aleshin, Alexander E; Gawlik, Katarzyna; Stec, Boguslaw; Frisch, Christian; Knappik, Achim; Strongin, Alex Y

    2010-05-01

    There is a need to develop inhibitors of mosquito-borne flaviviruses, including WNV (West Nile virus). In the present paper, we describe a novel and efficient recombinant-antibody technology that led us to the isolation of inhibitory high-affinity human antibodies to the active-site region of a viral proteinase. As a proof-of-principal, we have successfully used this technology and the synthetic naive human combinatorial antibody library HuCAL GOLD(R) to isolate selective and potent function-blocking active-site-targeting antibodies to the two-component WNV NS (non-structural protein) 2B-NS3 serine proteinase, the only proteinase encoded by the flaviviral genome. First, we used the wild-type enzyme in antibody screens. Next, the positive antibody clones were counter-screened using an NS2B-NS3 mutant with a single mutation of the catalytically essential active-site histidine residue. The specificity of the antibodies to the active site was confirmed by substrate-cleavage reactions and also by using proteinase mutants with additional single amino-acid substitutions in the active-site region. The selected WNV antibodies did not recognize the structurally similar viral proteinases from Dengue virus type 2 and hepatitis C virus, and human serine proteinases. Because of their high selectivity and affinity, the identified human antibodies are attractive reagents for both further mutagenesis and structure-based optimization and, in addition, for studies of NS2B-NS3 activity. Conceptually, it is likely that the generic technology reported in the present paper will be useful for the generation of active-site-specific antibody probes for multiple enzymes. PMID:20156198

  7. Preliminary error budget for an optical ranging system: Range, range rate, and differenced range observables

    NASA Technical Reports Server (NTRS)

    Folkner, W. M.; Finger, M. H.

    1990-01-01

    Future missions to the outer solar system or human exploration of Mars may use telemetry systems based on optical rather than radio transmitters. Pulsed laser transmission can be used to deliver telemetry rates of about 100 kbits/sec with an efficiency of several bits for each detected photon. Navigational observables that can be derived from timing pulsed laser signals are discussed. Error budgets are presented based on nominal ground stations and spacecraft-transceiver designs. Assuming a pulsed optical uplink signal, two-way range accuracy may approach the few centimeter level imposed by the troposphere uncertainty. Angular information can be achieved from differenced one-way range using two ground stations with the accuracy limited by the length of the available baseline and by clock synchronization and troposphere errors. A method of synchronizing the ground station clocks using optical ranging measurements is presented. This could allow differenced range accuracy to reach the few centimeter troposphere limit.

  8. Snowy Range Wilderness, Wyoming

    SciTech Connect

    Houston, R.S.; Bigsby, P.R.

    1984-01-01

    A mineral survey of the Snowy Range Wilderness was undertaken by the USGS and USBM in 1976-1978 and was followed up with more detailed geologic and geochemical surveys, culminating in diamond drilling of one hole in the Snowy Range Wilderness. No mineral deposits were identified in the Snowy Range Wilderness, but inasmuch as low-grade uranium and associated gold resources were identified in rocks similar to those of the northern Snowy Range Wilderness in an area about 5 mi northeast of the wilderness boundary, we conclude that the northern half of the wilderness has a probable-resource potential for uranium and gold. Closely spaced drilling would be required to completely evaluate this mineral potential. The geologic terrane precludes the occurrence of fossil fuels.

  9. Full range resistive thermometers

    NASA Astrophysics Data System (ADS)

    Olivieri, E.; Rotter, M.; De Combarieu, M.; Forget, P.; Marrache-Kikuchi, C.; Pari, P.

    2015-12-01

    Resistive thermometers are widely used in low temperature physics, thanks to portability, simplicity of operation and reduced size. The possibility to precisely follow the temperature from room temperature down to the mK region is of major interest for numerous applications, although no single thermometer can nowadays cover this entire temperature range. In this article we report on a method to realize a full range thermometer, capable to measure, by itself, temperatures in the whole above-cited temperature range, with constant sensitivity and sufficient precision for the typical cryogenic applications. We present here the first results for three different full range thermometer prototypes. A detailed description of the set-up used for measurements and characterization is also reported.

  10. Modelling Directional Solidification

    NASA Technical Reports Server (NTRS)

    Wilcox, William R.; Regel, Liya L.; Zhou, Jian; Yuan, Weijun

    1992-01-01

    The long range goal of this program has been to develop an improved understanding of phenomena of importance to directional solidification, in order to enable explanation and prediction of differences in behavior between solidification on Earth and in space. Current emphasis is on determining the influence of perturbations on directional solidification.

  11. Modelling directional solidification

    NASA Technical Reports Server (NTRS)

    Wilcox, William R.

    1991-01-01

    The long range goal of this program is to develop an improved understanding of phenomena of importance to directional solidification and to enable explanation and prediction of differences in behavior between solidification on Earth and in space. Current emphasis is on determining the influence of perturbations on directional solidification.

  12. Mu-2 ranging

    NASA Technical Reports Server (NTRS)

    Martin, W. L.; Zygielbaum, A. I.

    1977-01-01

    The Mu-II Dual-Channel Sequential Ranging System designed as a model for future Deep Space Network ranging equipment is described. A list of design objectives is followed by a theoretical explanation of the digital demodulation techniques first employed in this machine. Hardware and software implementation are discussed, together with the details relating to the construction of the device. Two appendixes are included relating to the programming and operation of this equipment to yield the maximum scientific data.

  13. Definition of Contravariant Velocity Components

    NASA Technical Reports Server (NTRS)

    Hung, Ching-Mao; Kwak, Dochan (Technical Monitor)

    2002-01-01

    This is an old issue in computational fluid dynamics (CFD). What is the so-called contravariant velocity or contravariant velocity component? In the article, we review the basics of tensor analysis and give the contravariant velocity component a rigorous explanation. For a given coordinate system, there exist two uniquely determined sets of base vector systems - one is the covariant and another is the contravariant base vector system. The two base vector systems are reciprocal. The so-called contravariant velocity component is really the contravariant component of a velocity vector for a time-independent coordinate system, or the contravariant component of a relative velocity between fluid and coordinates, for a time-dependent coordinate system. The contravariant velocity components are not physical quantities of the velocity vector. Their magnitudes, dimensions, and associated directions are controlled by their corresponding covariant base vectors. Several 2-D (two-dimensional) linear examples and 2-D mass-conservation equation are used to illustrate the details of expressing a vector with respect to the covariant and contravariant base vector systems, respectively.

  14. Component Technology for Laser Plasma Simulation

    SciTech Connect

    Bosl, W J; Smith, S G; Dahlgren, T; Epperley, T; Kohn, S; Kumfert, G

    2002-06-17

    This paper will discuss the application of high performance component software technology developed for a complex physics simulation development effort. The primary tool used to build software components is called Babel and is used to create language-independent libraries for high performance computers. Components were constructed from legacy code and wrapped with a thin Python layer to enable run-time scripting. Low-level components in Fortran, C++, and Python were composed directly as Babel components and invoked interactively from a parallel Python script.

  15. Analyzing growth components in trees.

    PubMed

    Guédon, Yann; Caraglio, Yves; Heuret, Patrick; Lebarbier, Emilie; Meredieu, Céline

    2007-10-01

    Observed growth, as given, for instance, by the length of successive annual shoots along the main axis of a plant, is mainly the result of two components: an ontogenetic component and an environmental component. An open question is whether the ontogenetic component along an axis at the growth unit or annual shoot scale takes the form of a trend or of a succession of phases. Various methods of analysis ranging from exploratory analysis (symmetric smoothing filters, sample autocorrelation functions) to statistical modeling (multiple change-point models, hidden semi-Markov chains and hidden hybrid model combining Markovian and semi-Markovian states) are applied to extract and characterize both the ontogenetic and environmental components using contrasted examples. This led us in particular to favor the hypothesis of an ontogenetic component structured as a succession of stationary phases and to highlight phase changes of high magnitude in unexpected situations (for instance, when growth globally decreases). These results shed light in a new way on botanical concepts such as "phase change" and "morphogenetic gradient". PMID:17631316

  16. Laser Ranging Simulation Program

    NASA Technical Reports Server (NTRS)

    Piazolla, Sabino; Hemmati, Hamid; Tratt, David

    2003-01-01

    Laser Ranging Simulation Program (LRSP) is a computer program that predicts selected aspects of the performances of a laser altimeter or other laser ranging or remote-sensing systems and is especially applicable to a laser-based system used to map terrain from a distance of several kilometers. Designed to run in a more recent version (5 or higher) of the MATLAB programming language, LRSP exploits the numerical and graphical capabilities of MATLAB. LRSP generates a graphical user interface that includes a pop-up menu that prompts the user for the input of data that determine the performance of a laser ranging system. Examples of input data include duration and energy of the laser pulse, the laser wavelength, the width of the laser beam, and several parameters that characterize the transmitting and receiving optics, the receiving electronic circuitry, and the optical properties of the atmosphere and the terrain. When the input data have been entered, LRSP computes the signal-to-noise ratio as a function of range, signal and noise currents, and ranging and pointing errors.

  17. Robotic component preparation

    SciTech Connect

    Dokos, J.R.

    1986-04-01

    This report provides information on the preparation of robotic components. Component preparation includes pretinning or solder dipping, preforming, and pretrimming of component leads. Since about 70% of all components are axial-leaded resistor-type components, it was decided to begin with them and then later develop capabilities to handle other types. The first workcell is the first phase of an overall system to pretin, preform, and pretrim all components and to feed them to an automatic insertion system. Before use of the robot, a Unimation PUMA Modal 260, pretinning and preforming was done by first hand with a shield and vented booth.

  18. Long range metrological atomic force microscope with versatile measuring head

    NASA Astrophysics Data System (ADS)

    Lu, Mingzhen; Gao, Sitian; Li, Qi; Li, Wei; Shi, Yushu; Tao, Xingfu

    2013-01-01

    A long range metrological atomic force microscope (AFM) has been developed at NIM. It aims to realize a maximum measurement volume of 50mm×50mm×2mm with an uncertainty of a few tens of nanometers in the whole range. In compliance with Abbe Principle, the instrument is designed as a sample-scanning type. The sample is moved by a 6-DOF piezostage in combination with a hybrid slide-air bearing stage for long scanning range. Homodyne interferometers with four passes attached to a metrological frame measure relative displacement between the probe and sample thus the instrument is directly traceable to the SI. An AFM head is developed as the measuring head for the instrument. Considering accuracy and dynamic performance of the instrument, it is designed to be capable of scanning perpendicularly in a range of 5μm×5μm×5μm with a 3-DOF piezostage. Optical beam deflection method is used and a minimum of components are mounted on the moving part. A novel design is devised so that the photodetector is only sensitive to the deflection of cantilever, but not the displacement of the head. Moving manner of the head varies with scanning range and mode of the instrument. Results of different measurements are demonstrated, showing the excellent performance of the instrument.

  19. The range scheduling aid

    NASA Technical Reports Server (NTRS)

    Halbfinger, Eliezer M.; Smith, Barry D.

    1991-01-01

    The Air Force Space Command schedules telemetry, tracking and control activities across the Air Force Satellite Control network. The Range Scheduling Aid (RSA) is a rapid prototype combining a user-friendly, portable, graphical interface with a sophisticated object-oriented database. The RSA has been a rapid prototyping effort whose purpose is to elucidate and define suitable technology for enhancing the performance of the range schedulers. Designing a system to assist schedulers in their task and using their current techniques as well as enhancements enabled by an electronic environment, has created a continuously developing model that will serve as a standard for future range scheduling systems. The RSA system is easy to use, easily ported between platforms, fast, and provides a set of tools for the scheduler that substantially increases his productivity.

  20. Initial Ada components evaluation

    NASA Technical Reports Server (NTRS)

    Moebes, Travis

    1989-01-01

    The SAIC has the responsibility for independent test and validation of the SSE. They have been using a mathematical functions library package implemented in Ada to test the SSE IV and V process. The library package consists of elementary mathematical functions and is both machine and accuracy independent. The SSE Ada components evaluation includes code complexity metrics based on Halstead's software science metrics and McCabe's measure of cyclomatic complexity. Halstead's metrics are based on the number of operators and operands on a logical unit of code and are compiled from the number of distinct operators, distinct operands, and total number of occurrences of operators and operands. These metrics give an indication of the physical size of a program in terms of operators and operands and are used diagnostically to point to potential problems. McCabe's Cyclomatic Complexity Metrics (CCM) are compiled from flow charts transformed to equivalent directed graphs. The CCM is a measure of the total number of linearly independent paths through the code's control structure. These metrics were computed for the Ada mathematical functions library using Software Automated Verification and Validation (SAVVAS), the SSE IV and V tool. A table with selected results was shown, indicating that most of these routines are of good quality. Thresholds for the Halstead measures indicate poor quality if the length metric exceeds 260 or difficulty is greater than 190. The McCabe CCM indicated a high quality of software products.

  1. Carcinogenicity of hair dye components.

    PubMed

    Van Duuren, B L

    1980-03-01

    The available animal carcinogenicity data on hair dye components was reviewed. From this review it became clear that certain hair dye components, some of which are still in hair dye formulations now on the market, are animal carcinogens. The compounds of concern that are still in use are: 3-amino-4-methoxyaniline, 2-nitro-4-aminoaniline and 3-nitro-4-hydroxyaniline. Certain azo dyes formerly used, and related compounds still in use, contain the benzidine moiety. Two of these compounds, Direct Blue 6 and Direct Black 38, have been shown to be metabolized in animals to the human carcinogen benzidine. Furthermore, skin absorption studies carried out with radiolabeled hair dye components applied to animal or human skin have conclusively shown that these compounds are systemically absorbed and excreted. Known cocarcinogens such as catechol and pyrogallol, which enhance benzo(a)pyrene carcinogenicity on mouse skin, are used as hair dye components. It is not known whether such compounds will enhance the carcinogenicity of substituted aniline hair dye chemicals. The available epidemiologic data are not sufficient to link hair dye use with an increased incidence in human cancer. PMID:6993608

  2. Fabrication of plastic microfluidic components

    NASA Astrophysics Data System (ADS)

    Martin, Peter M.; Matson, Dean W.; Bennett, Wendy D.; Hammerstrom, D. J.

    1998-09-01

    Plastic components have many advantages, including ease of fabrication, low cost, chemical inertness, lightweight, and disposability. We report on the fabrication of three plastics-based microfluidic components: a motherboard, a dialysis unit, and a metal sensor. Microchannels, headers, and interconnects were produced in thin sheets (>=50 microns) of polyimide, PMMA, polyethylene, and polycarbonate using a direct-write excimer laser micromachining system. Machined sheets were laminated by thermal and adhesive bonding to form leak-tight microfluidic components. The microfluidic motherboard borrowed the `functionality on a chip' concept from the electronics industry and was the heart of a complex microfluidic analytical device. The motherboard platform was designed to be tightly integrated and self-contained (i.e., liquid flows are all confined within machined microchannels), reducing the need for tubing with fluid distribution and connectivity. This concept greatly facilitated system integration and miniaturization. As fabricated, the motherboard consisted of three fluid reservoirs connected to micropumps by microchannels. The fluids could either be pumped independently or mixed in microchannels prior to being directed to exterior analytical components via outlet ports. The microdialysis device was intended to separate electrolytic solutes from low volume samples prior to mass spectrometric analysis. The device consisted of a dialysis membrane laminated between opposed serpentine microchannels containing the sample fluid and a buffer solution. The laminated metal sensor consisted of fluid reservoirs, micro-flow channels, micropumps, mixing channels, reaction channels, and detector circuitry.

  3. Satellite Laser Ranging operations

    NASA Technical Reports Server (NTRS)

    Pearlman, Michael R.

    1994-01-01

    Satellite Laser Ranging (SLR) is currently providing precision orbit determination for measurements of: 1) Ocean surface topography from satellite borne radar altimetry, 2) Spatial and temporal variations of the gravity field, 3) Earth and ocean tides, 4) Plate tectonic and regional deformation, 5) Post-glacial uplift and subsidence, 6) Variations in the Earth's center-of-mass, and 7) Variations in Earth rotation. SLR also supports specialized programs in time transfer and classical geodetic positioning, and will soon provide precision ranging to support experiments in relativity.

  4. Western Aeronautical Test Range

    NASA Technical Reports Server (NTRS)

    Sakahara, Robert D.

    2008-01-01

    This viewgraph presentation reviews the work of the Western Aeronautical Test Range (WATR). NASA's Western Aeronautical Test Range is a network of facilities used to support aeronautical research, science missions, exploration system concepts, and space operations. The WATR resides at NASA's Dryden Flight Research Center located at Edwards Air Force Base, California. The WATR is a part of NASA's Corporate Management of Aeronautical Facilities and funded by the Strategic Capability Asset Program (SCAP). Maps show the general location of the WATR area that is used for aeronautical testing and evaluation. The products, services and facilities of WATR are discussed,

  5. Mobile satellite ranging

    NASA Technical Reports Server (NTRS)

    Silverberg, E. C.

    1978-01-01

    A brief review of the constraints which have limited satellite ranging hardware and an outline of the steps which are underway to improve the status of the equipment in this area are given. In addition, some suggestions are presented for the utilization of newer instruments and for possible future research and development work in this area.

  6. STDN ranging equipment

    NASA Technical Reports Server (NTRS)

    Jones, C. E.

    1975-01-01

    Final results of the Spaceflight Tracking and Data Network (STDN) Ranging Equipment program are summarized. Basic design concepts and final design approaches are described. Theoretical analyses which define requirements and support the design approaches are presented. Design verification criteria are delineated and verification test results are specified.

  7. Agriculture, forest, and range

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The findings and recommendations of the panel for developing a satellite remote-sensing global information system in the next decade are reported. User requirements were identified in five categories: (1) cultivated crops, (2) land resources, (3)water resources, (4)forest management, and (5) range management. The benefits from the applications of satellite data are discussed.

  8. Agriculture, forestry, range resources

    NASA Technical Reports Server (NTRS)

    Crea, W. J.

    1974-01-01

    In the area of crop specie identification, it has been found that temporal data analysis, preliminary stratification, and unequal probability analysis were several of the factors that contributed to high identification accuracies. Single data set accuracies on fields of greater than 80,000 sq m (20 acres) are in the 70- to 90-percent range; however, with the use of temporal data, accuracies of 95 percent have been reported. Identification accuracy drops off significantly on areas of less than 80,000 sq m (20 acres) as does measurement accuracy. Forest stratification into coniferous and deciduous areas has been accomplished to a 90- to 95-percent accuracy level. Using multistage sampling techniques, the timber volume of a national forest district has been estimated to a confidence level and standard deviation acceptable to the Forest Service at a very favorable cost-benefit time ratio. Range specie/plant community vegetation mapping has been accomplished at various levels of success (69- to 90-percent accuracy). However, several investigators have obtained encouraging initial results in range biomass (forage production) estimation and range readiness predictions. Soil association map correction and soil association mapping in new area appear to have been proven feasible on large areas; however, testing in a complex soil area should be undertaken.

  9. Agriculture, forestry, range resources

    NASA Technical Reports Server (NTRS)

    Macdonald, R. B.

    1974-01-01

    The necessary elements to perform global inventories of agriculture, forestry, and range resources are being brought together through the use of satellites, sensors, computers, mathematics, and phenomenology. Results of ERTS-1 applications in these areas, as well as soil mapping, are described.

  10. Fact Sheet: Range Complex

    NASA Technical Reports Server (NTRS)

    Cornelson, C.; Fretter, E.

    2004-01-01

    NASA Ames has a long tradition in leadership with the use of ballistic ranges and shock tubes for the purpose of studying the physics and phenomena associated with hypervelocity flight. Cutting-edge areas of research run the gamut from aerodynamics, to impact physics, to flow-field structure and chemistry. This legacy of testing began in the NACA era of the 1940's with the Supersonic Free Flight Tunnel, and evolved dramatically up through the late 1950s with the pioneering work in the Ames Hypersonic Ballistic Range. The tradition continued in the mid-60s with the commissioning of the three newest facilities: the Ames Vertical Gun Range (AVGR) in 1964, the Hypervelocity Free Flight Facility (HFFF) in 1965 and the Electric Arc Shock Tube (EAST) in 1966. Today the Range Complex continues to provide unique and critical testing in support of the Nation's programs for planetary geology and geophysics; exobiology; solar system origins; earth atmospheric entry, planetary entry, and aerobraking vehicles; and various configurations for supersonic and hypersonic aircraft.

  11. RADIO RANGING DEVICE

    DOEpatents

    Bogle, R.W.

    1960-11-22

    A description is given of a super-regenerative oscillator ranging device provided with radiating and receiving means and being capable of indicating the occurrence of that distance between itself and a reflecting object which so phases the received echo of energy of a preceding emitted oscillation that the intervals between oscillations become uniform.

  12. Front Range Branch Officers

    NASA Astrophysics Data System (ADS)

    The Front Range Branch of AGU has installed officers for 1990: Ray Noble, National Center for Atmospheric Research, chair; Sherry Oaks, U.S. Geological Survey, chair-elect; Howard Garcia, NOAA, treasurer; Catharine Skokan, Colorado School of Mines, secretary. JoAnn Joselyn of NOAA is past chair. Members at large are Wallace Campbell, NOAA; William Neff, USGS; and Stephen Schneider, NCAR.

  13. Software component quality evaluation

    NASA Technical Reports Server (NTRS)

    Clough, A. J.

    1991-01-01

    The paper describes a software inspection process that can be used to evaluate the quality of software components. Quality criteria, process application, independent testing of the process and proposed associated tool support are covered. Early results indicate that this technique is well suited for assessing software component quality in a standardized fashion. With automated machine assistance to facilitate both the evaluation and selection of software components, such a technique should promote effective reuse of software components.

  14. Space-Based Range

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Space-Based Range (SBR), previously known as Space-Based Telemetry and Range Safety (STARS), is a multicenter NASA proof-of-concept project to determine if space-based communications using NASA's Tracking and Data Relay Satellite System (TDRSS) can support the Range Safety functions of acquiring tracking data and generating flight termination signals, while also providing broadband Range User data such as voice, video, and vehicle/payload data. There was a successful test of the Range Safety system at Wallops Flight Facility (WFF) on December 20, 2005, on a two-stage Terrier-Orion spin-stabilized sounding rocket. SBR transmitted GPS tracking data and maintained links with two TDRSS satellites simultaneously during the 10-min flight. The payload section deployed a parachute, landed in the Atlantic Ocean about 90 miles downrange from the launch site, and was successfully recovered. During the Terrier-Orion tests flights, more than 99 percent of all forward commands and more than 95 percent of all return frames were successfully received and processed. The time latency necessary for a command to travel from WFF over landlines to White Sands Complex and then to the vehicle via TDRSS, be processed onboard, and then be sent back to WFF was between 1.0 s and 1.1 s. The forward-link margins for TDRS-10 (TDRS East [TDE]) were 11 dB to 12 dB plus or minus 2 dB, and for TDRS-4 (TDRS Spare [TDS]) were 9 dB to 10 dB plus or minus 1.5 dB. The return-link margins for both TDE and TDS were 6 dB to 8 dB plus or minus 3 dB. There were 11 flights on an F-15B at Dryden Flight Research Center (DFRC) between November 2006 and February 2007. The Range User system tested a 184-element TDRSS Ku-band (15 GHz) phased-array antenna with data rates of 5 Mbps and 10 Mbps. This data was a combination of black-and-white cockpit video, Range Safety tracking and transceiver data, and aircraft and antenna controller data streams. IP data formatting was used.

  15. Reactor component automatic grapple

    SciTech Connect

    Greenaway, P.R.

    1982-12-07

    A grapple for handling nuclear reactor components in a medium such as liquid sodium which, upon proper seating and alignment of the grapple with the component as sensed by a mechanical logic integral to the grapple, automatically seizes the component. The mechanical logic system also precludes seizure in the absence of proper seating and alignment.

  16. Reactor component automatic grapple

    DOEpatents

    Greenaway, Paul R.

    1982-01-01

    A grapple for handling nuclear reactor components in a medium such as liquid sodium which, upon proper seating and alignment of the grapple with the component as sensed by a mechanical logic integral to the grapple, automatically seizes the component. The mechanical logic system also precludes seizure in the absence of proper seating and alignment.

  17. Modeling human echolocation of near-range targets with an audible sonar.

    PubMed

    Kuc, Roman; Kuc, Victor

    2016-02-01

    Blind humans echolocate nearby targets by emitting palatal clicks and perceiving echoes that the auditory system is not able to resolve temporally. The mechanism for perceiving near-range echoes is not known. This paper models the direct mouth-to-ear signal (MES) and the echo to show that the echo enhances the high-frequency components in the composite MES/echo signal with features that allow echolocation. The mouth emission beam narrows with increasing frequency and exhibits frequency-dependent transmission notches in the backward direction toward the ears as predicted by the piston-in-sphere model. The ears positioned behind the mouth detect a MES that contains predominantly the low frequencies contained in the emission. Hence the high-frequency components in the emission that are perceived by the ears are enhanced by the echoes. A pulse/echo audible sonar verifies this model by echolocating targets from 5 cm range, where the MES and echo overlap significantly, to 55 cm. The model predicts that unambiguous ranging occurs over a limited range and that there is an optimal range that produces the highest range resolution. PMID:26936542

  18. New directions in lubrication, materials, wear, and surface interactions - Tribology in the 80's

    NASA Technical Reports Server (NTRS)

    Loomis, W. R. (Editor)

    1985-01-01

    New directions in tribology are described. A range of topics is addressed, extending from fundamental research on tribological materials of all kinds and their surface effects, to final technological applications in mechanical components such as bearings, gears, and seals. The general topics addressed include: importance and definition of materials in tribology; future directions of research in adhesion and friction, wear and wear-resistant materials, and liquid lubricants and additives; status and new directions in elastohydrodynamic lubrication and solid lubricants; and tribological materials for mechanical components of the future.

  19. Range reference atmosphere models

    NASA Technical Reports Server (NTRS)

    Smith, O. E.; Galusha, B. W.

    1983-01-01

    A description is given of the methods used to establish the statistical parameters and models for wind and various thermodynamic quantities at an altitude of 0-70 km for nine geographical locations. It is noted that wind is modeled as a vector quantity using the bivariate normal probability function. With the five parameters of the bivariate normal distribution, the distribution for wind speed is derived as a generalized Rayleigh distribution. In addition, the frequency of wind direction is derived, and the conditional distribution of wind speed given the wind direction is derived. It is pointed out that these and other wind models are consistent with the rigorous mathematical properties of the bivariate normal probability theory. The thermodynamic quantities are consistent with the hydrostatic equation and the equation of state for the mean values. With these methods, many statistical relationships can be derived.

  20. Perceptual quantization of chromatic components

    NASA Astrophysics Data System (ADS)

    Saadane, Abdelhakim; Bedat, Laurent; Barba, Dominique

    1998-07-01

    In order to achieve a color image coding based on the human visual system features, we have been interested by the design of a perceptually based quantizer. The cardinal directions Ach, Cr1 and Cr2, designed by Krauskopf from habituation experiments and validated in our lab from spatial masking experiments, have been used to characterize color images. The achromatic component, already considered in previous study, will not be considered here. The same methodology has been applied to the two chromatic components to specify the decision thresholds and the reconstruction levels which ensure that the degradations induced will be lower than their visibility thresholds. Two observers have been used for each of the two components. From the values obtained for Cr1 component one should notice that the decision thresholds and reconstruction levels follow a linear law even at higher levels. However, for Cr2 component the values seem following a monotonous increasing function. To determine if these behaviors are frequency dependent, further experiments have been conducted with stimulus frequencies varying from 1cy/deg to 4cy/deg. The measured values show no significant variations. Finally, instead of sinusoidal stimuli, filtered textures have been used to take into account the spatio-frequential combination. The same laws (linear for Cr1 and monotonous increasing for Cr2) have been observed even if a variation in the quantization intervals is reported.

  1. Light beam range finder

    DOEpatents

    McEwan, Thomas E.

    1998-01-01

    A "laser tape measure" for measuring distance which includes a transmitter such as a laser diode which transmits a sequence of electromagnetic pulses in response to a transmit timing signal. A receiver samples reflections from objects within the field of the sequence of visible electromagnetic pulses with controlled timing, in response to a receive timing signal. The receiver generates a sample signal in response to the samples which indicates distance to the object causing the reflections. The timing circuit supplies the transmit timing signal to the transmitter and supplies the receive timing signal to the receiver. The receive timing signal causes the receiver to sample the reflection such that the time between transmission of pulses in the sequence in sampling by the receiver sweeps over a range of delays. The transmit timing signal causes the transmitter to transmit the sequence of electromagnetic pulses at a pulse repetition rate, and the received timing signal sweeps over the range of delays in a sweep cycle such that reflections are sampled at the pulse repetition rate and with different delays in the range of delays, such that the sample signal represents received reflections in equivalent time. The receiver according to one aspect of the invention includes an avalanche photodiode and a sampling gate coupled to the photodiode which is responsive to the received timing signal. The transmitter includes a laser diode which supplies a sequence of visible electromagnetic pulses. A bright spot projected on to the target clearly indicates the point that is being measured, and the user can read the range to that point with precision of better than 0.1%.

  2. Light beam range finder

    DOEpatents

    McEwan, T.E.

    1998-06-16

    A ``laser tape measure`` for measuring distance is disclosed which includes a transmitter such as a laser diode which transmits a sequence of electromagnetic pulses in response to a transmit timing signal. A receiver samples reflections from objects within the field of the sequence of visible electromagnetic pulses with controlled timing, in response to a receive timing signal. The receiver generates a sample signal in response to the samples which indicates distance to the object causing the reflections. The timing circuit supplies the transmit timing signal to the transmitter and supplies the receive timing signal to the receiver. The receive timing signal causes the receiver to sample the reflection such that the time between transmission of pulses in the sequence in sampling by the receiver sweeps over a range of delays. The transmit timing signal causes the transmitter to transmit the sequence of electromagnetic pulses at a pulse repetition rate, and the received timing signal sweeps over the range of delays in a sweep cycle such that reflections are sampled at the pulse repetition rate and with different delays in the range of delays, such that the sample signal represents received reflections in equivalent time. The receiver according to one aspect of the invention includes an avalanche photodiode and a sampling gate coupled to the photodiode which is responsive to the received timing signal. The transmitter includes a laser diode which supplies a sequence of visible electromagnetic pulses. A bright spot projected on to the target clearly indicates the point that is being measured, and the user can read the range to that point with precision of better than 0.1%. 7 figs.

  3. Highly directional acoustic receivers.

    PubMed

    Cray, Benjamin A; Evora, Victor M; Nuttall, Albert H

    2003-03-01

    The theoretical directivity of a single combined acoustic receiver, a device that can measure many quantities of an acoustic field at a collocated point, is presented here. The formulation is developed using a Taylor series expansion of acoustic pressure about the origin of a Cartesian coordinate system. For example, the quantities measured by a second-order combined receiver, denoted a dyadic sensor, are acoustic pressure, the three orthogonal components of acoustic particle velocity, and the nine spatial gradients of the velocity vector. The power series expansion, which can be of any order, is cast into an expression that defines the directivity of a single receiving element. It is shown that a single highly directional dyadic sensor can have a directivity index of up to 9.5 dB. However, there is a price to pay with highly directive sensors; these sensors can be significantly more sensitive to nonacoustic noise sources. PMID:12656387

  4. Front Range Report, Abstracts

    NASA Astrophysics Data System (ADS)

    Spence, William

    The second regional conference of the Front Range Branch, AGU, was attended by more than 80 professionals and some 20 outstanding high school students. The conference included 2 days of interdisciplinary talks, and lots of discussion, that primarily were keyed to geophysical studies of Colorado, Wyoming, and New Mexico. Other talks reported on nonregional, and sometimes global, studies being done by geophypsicists of the Front Range region.Topics included tectonics of the Front Range and the Colorado Plateau, pollution of the Arkansas and Mississippi rivers, and a supreme polluting event that caused the late-Cretaceous extinctions. Other notable talks were on toxic cleanup, microburst (wind shear) detection at U.S. airports, and other meteorological studies. Several talks treated the audience to the excitement of new work and surprise discoveries. The meeting was multimedia, including the playing of two videos through a projection TV and the playing of a fascinating tape between an airport control tower and incoming pilots during a severe microburst event.

  5. Organic sonobuoy ranging

    NASA Astrophysics Data System (ADS)

    Felgate, Nick

    2002-11-01

    It is important that military vessels periodically check their passive signatures for vunerabilities. Traditionally, this is undertaken on a fixed range (e.g., AUTEC, BUTEC) with low noise conditions. However, for operational and cost reasons it is desirable to be able to undertake such measurements while the asset is operating in other areas using expendable buoys deployed by the vessel itself. As well as the wet-end hardware for such organic sonobuoy ranging systems (e.g., calibrated sonobuoys, calibrated data uplink channels), careful consideration is needed of the signal-processing required in the harsher environmental conditions of the open ocean. In particular, it is noted that the open ocean is usually much noisier, and the propagation conditions more variable. To overcome signal-to-noise problems, techniques such as Doppler-correction, zero-padding/peak-picking, and noise estimation/correction techniques have been developed to provide accurate and unbiased estimates of received levels. To estimate propagation loss for source level estimation, a model of multipath effects has been included with the ability for analysts to compare predicted and observed received levels against time/range and adjust modeling parameters (e.g., surface loss, bottom loss, source depth) to improve the fit.

  6. Failure Analysis of Ceramic Components

    SciTech Connect

    B.W. Morris

    2000-06-29

    Ceramics are being considered for a wide range of structural applications due to their low density and their ability to retain strength at high temperatures. The inherent brittleness of monolithic ceramics requires a departure from the deterministic design philosophy utilized to analyze metallic structural components. The design program ''Ceramic Analysis and Reliability Evaluation of Structures Life'' (CARES/LIFE) developed by NASA Lewis Research Center uses a probabilistic approach to predict the reliability of monolithic components under operational loading. The objective of this study was to develop an understanding of the theories used by CARES/LIFE to predict the reliability of ceramic components and to assess the ability of CARES/LIFE to accurately predict the fast fracture behavior of monolithic ceramic components. A finite element analysis was performed to determine the temperature and stress distribution of a silicon carbide O-ring under diametral compression. The results of the finite element analysis were supplied as input into CARES/LIFE to determine the fast fracture reliability of the O-ring. Statistical material strength parameters were calculated from four-point flexure bar test data. The predicted reliability showed excellent correlation with O-ring compression test data indicating that the CARES/LIFE program can be used to predict the reliability of ceramic components subjected to complicated stress states using material properties determined from simple uniaxial tensile tests.

  7. Affordable WDM components: the polymer solution

    NASA Astrophysics Data System (ADS)

    Eldada, Louay A.; Yin, Shing; Norwood, Robert A.; Yardley, James T.

    1998-02-01

    An advanced polymeric waveguide technology was developed for affordable WDM components that address the needs of both the Telecom and the Datacom industries. We engineered high- performance organic polymers that can be readily made into both multimode and single-mode optical waveguide structures of controlled numerical aperture and geometry. These materials are formed from highly-crosslinked acrylate monomers with specific linkages that determine properties such as flexibility, toughness, loss, and environmental stability. These monomers are intermiscible, providing for precise adjustment of the refractive index from 1.3 to 1.6. In polymer form, they exhibit state-of-the-art loss values, high thermal stability, high humidity resistance, low dispersion and low birefringence. Waveguides are formed photolithographically, with the liquid monomer mixture polymerizing upon illumination in the UV via either mask exposure or laser direct writing. A wide range of rigid and flexible substrates can be used, including glass, quartz, oxidized silicon, glass-filled epoxy printed circuit board substrate, and flexible polyimide film. Waveguiding structures measuring tens of inches in length can be produced on computer boards, and guides that are meters long can be printed on rolls of plastic. We describe the fabrication of both Bragg gratings and waveguide grating routes in our polymers for filtering and demultiplexing applications in Telecom WDM systems. In Datacom, we describe polymeric components that we produced for aerospace WDM sensor systems. The importance of CAD tools in designing WDM devices is emphasized in this work. We further discuss the low-cost manufacturing of WDM components in an industrial environment.

  8. Optical components damage parameters database system

    NASA Astrophysics Data System (ADS)

    Tao, Yizheng; Li, Xinglan; Jin, Yuquan; Xie, Dongmei; Tang, Dingyong

    2012-10-01

    Optical component is the key to large-scale laser device developed by one of its load capacity is directly related to the device output capacity indicators, load capacity depends on many factors. Through the optical components will damage parameters database load capacity factors of various digital, information technology, for the load capacity of optical components to provide a scientific basis for data support; use of business processes and model-driven approach, the establishment of component damage parameter information model and database systems, system application results that meet the injury test optical components business processes and data management requirements of damage parameters, component parameters of flexible, configurable system is simple, easy to use, improve the efficiency of the optical component damage test.

  9. Paleomagnetism, paleogeographic origins, and uplift history of the Coast Range ophiolite at Mount Diablo, California

    USGS Publications Warehouse

    Hagstrum, J.T.; Jones, D.L.

    1998-01-01

    Divergent paleogeographic origins have been proposed for the Coast Range ophiolite of western California which are testable using paleomagnetic methods. Paleomagnetic data for Middle Jurassic pillow lavas and diabase sills of the Coast Range ophiolite at Mount Diablo, northern California, indicate that they contain two components of remanent magnetization. The characteristic directions have normal and reversed polarities and apparently are carried by Ti-poor magnetite. This magnetization is inferred to have been acquired during emplacement and seafloor alteration at an ancient spreading ridge. The paleolatitude calculated from its structurally corrected mean direction is 20??N ?? 9?? and agrees with the expected direction for stable North America; this result is also consistent with the concordant paleolatitude (32??N ?? 8??) recently determined for Upper Jurassic Coast Range ophiolite at Stanley Mountain in southern California. In addition, clockwise vertical axis rotation of Mount Diablo (143?? ?? 11??) is indicated by the characteristic magnetization direction. An overprint component is inferred to have been acquired during uplift of Mount Diablo since the Miocene.

  10. Exploration of polygonal environments using range data.

    PubMed

    Ekman, A; Torne, A; Stromberg, D

    1997-01-01

    Several robotic problems involve the systematic traversal of the environment, commonly referred to as exploration. We present a strategy for the exploration of unknown finite polygonal environments, using a point robot with 1) no positional uncertainty and 2) an ideal range sensor that measures range in N uniformly distributed directions. The range data vector, obtained from the range sensor, corresponds to a sampled version of a visibility polygon. Visibility polygon edges that do not correspond to environmental edges are called jump edges and the exploration strategy is based on the fact that jump edges indicate directions of possibly unexplored environmental regions. We describe conditions under which it is possible to identify jump edges in the range data. We also show how the exploration strategy can be used in a solution to the terrain acquisition problem and describe conditions under which a solution is guaranteed within a finite number of measurements. PMID:18255863

  11. Neutron range spectrometer

    DOEpatents

    Manglos, S.H.

    1988-03-10

    A neutron range spectrometer and method for determining the neutron energy spectrum of a neutron emitting source are disclosed. Neutrons from the source are colliminated along a collimation axis and a position sensitive neutron counter is disposed in the path of the collimated neutron beam. The counter determines positions along the collimation axis of interactions between the neutrons in the neutron beam and a neutron-absorbing material in the counter. From the interaction positions, a computer analyzes the data and determines the neutron energy spectrum of the neutron beam. The counter is preferably shielded and a suitable neutron-absorbing material is He-3. 1 fig.

  12. Gas cooking range

    SciTech Connect

    Narang, R.K.; Narang, K.

    1984-02-14

    An energy-efficient gas cooking range features an oven section with improved heat circulation and air preheat, a compact oven/broiler burner, a smoke-free drip pan, an efficient piloted ignition, flame-containing rangetop burner rings, and a small, portable oven that can be supported on the burner rings. Panels spaced away from the oven walls and circulation fans provide very effective air flow within the oven. A gas shutoff valve automatically controls the discharge of heated gases from the oven so that they are discharged only when combustion is occurring.

  13. Assessment HVOF sprayed coatings for reducing wear on pump components

    SciTech Connect

    Kaufold, R.; McCaul, C.; Brunhouse, S.

    1994-12-31

    Long-term pump efficiency and durability are directly related to the wear and corrosion resistance of materials used to manufacture pump components. Conventional OEM design materials often do not provide long-term resistance to wear caused by abrasive grains, particle erosion, corrosion, and cavitation. As a result, pump components can fail prematurely causing pump downtime and interrupting service life. Thermal-sprayed coatings, in particular, those deposited by HVOF, can help prevent this loss by reducing premature pump failure resulting from accelerated wear. The intent of this paper is to assess the degree of wear protection provided by various materials deposited by HVOF as compared to those coatings accepted by pump manufacturers. The materials tested ranged from tungsten carbide to chromium carbide to nickel-base alloys. The coating properties were analyzed by metallographic characterization, abrasive wear, corrosive wear, and anti-galling.

  14. The contribution of the diffuse light component to the topographic effect on remotely sensed data

    NASA Technical Reports Server (NTRS)

    Justice, C.; Holben, B.

    1980-01-01

    The topographic effect is measured by the difference between the global radiance from inclined surfaces as a function of their orientation relative to the sensor position and light source. The short wave radiant energy incident on a surface is composed of direct sunlight, scattered skylight, and light reflected from surrounding terrain. The latter two components are commonly known as the diffuse component. The contribution of the diffuse light component to the topographic effect was examined and the significance of this diffuse component with respect to two direct radiance models was assessed. Diffuse and global spectral radiances were measured for a series of slopes and aspects of a uniform and surface in the red and photographic infrared parts of the spectrum, using a nadir pointing two channel handheld radiometer. The diffuse light was found to produce a topographic effect which varied from the topographic effect for direct light. The topographic effect caused by diffuse light was found to increase slightly with solar elevation and wavelength for the channels examined. The correlations between data derived from two simple direct radiance simulation models and the field data were not significantly affected when the diffuse component was removed from the radiances. Radiances from a 60 percent reflective surface, assuming no atmospheric path radiance, the diffuse light topographic effect contributed a maximum range of 3 pixel values in simulated LANDSAT data from all aspects with slopes up to 30 degrees.

  15. The Dissipation Range in Rotating Turbulence

    NASA Technical Reports Server (NTRS)

    Rubinstein, Robert; Zhou, Ye

    1999-01-01

    The dissipation range energy balance of the direct interaction approximation is applied to rotating turbulence when rotation effects persist well into the dissipation range. Assuming that RoRe (exp 1/2) is much less than 1 and that three-wave interactions are dominant, the dissipation range is found to be concentrated in the wavevector plane perpendicular to the rotation axis. This conclusion is consistent with previous analyses of inertial range energy transfer in rotating turbulence, which predict the accumulation of energy in those scales.

  16. Monocular visual ranging

    NASA Astrophysics Data System (ADS)

    Witus, Gary; Hunt, Shawn

    2008-04-01

    The vision system of a mobile robot for checkpoint and perimeter security inspection performs multiple functions: providing surveillance video, providing high resolution still images, and providing video for semi-autonomous visual navigation. Mid-priced commercial digital cameras support the primary inspection functions. Semi-autonomous visual navigation is a tertiary function whose purpose is to reduce the burden of teleoperation and free the security personnel for their primary functions. Approaches to robot visual navigation require some form of depth perception for speed control to prevent the robot from colliding with objects. In this paper present the initial results of an exploration of the capabilities and limitations of using a single monocular commercial digital camera for depth perception. Our approach combines complementary methods in alternating stationary and moving behaviors. When the platform is stationary, it computes a range image from differential blur in the image stack collected at multiple focus settings. When the robot is moving, it extracts an estimate of range from the camera auto-focus function, and combines this with an estimate derived from angular expansion of a constellation of visual tracking points.

  17. Western Aeronautical Test Range

    NASA Technical Reports Server (NTRS)

    Sakahara, Robert D.

    2008-01-01

    NASA's Western Aeronautical Test Range (WATR) is a network of facilities used to support aeronautical research, science missions, exploration system concepts, and space operations. The WATR resides at NASA's Dryden Flight Research Center located at Edwards Air Force Base, California. The WATR is a part of NASA's Corporate Management of Aeronautical Facilities and funded by the Strategic Capability Asset Program (SCAP). It is managed by the Aeronautics Test Program (ATP) of the Aeronautics Research Mission Directorate (ARMD) to provide the right facility at the right time. NASA is a tenant on Edwards Air Force Base and has an agreement with the Air Force Flight Test Center to use the land and airspace controlled by the Department of Defense (DoD). The topics include: 1) The WATR supports a variety of vehicles; 2) Dryden shares airspace with the AFFTC; 3) Restricted airspace, corridors, and special use areas are available for experimental aircraft; 4) WATR Products and Services; 5) WATR Support Configuration; 6) Telemetry Tracking; 7) Time Space Positioning; 8) Video; 9) Voice Communication; 10) Mobile Operations Facilities; 11) Data Processing; 12) Mission Control Center; 13) Real-Time Data Analysis; and 14) Range Safety.

  18. MiniAERCam Ranging

    NASA Technical Reports Server (NTRS)

    Talley, Tom

    2003-01-01

    Johnson Space Center (JSC) is designing a small, remotely controlled vehicle that will carry two color and one black and white video cameras in space. The device will launch and retrieve from the Space Vehicle and be used for remote viewing. Off the shelf cellular technology is being used as the basis for communication system design. Existing plans include using multiple antennas to make simultaneous estimates of the azimuth of the MiniAERCam from several sites on the Space Station and use triangulation to find the location of the device. Adding range detection capability to each of the nodes on the Space Vehicle would allow an estimate of the location of the MiniAERCam to be made at each Communication And Telemetry Box (CATBox) independent of all the other communication nodes. This project will investigate the techniques used by the Global Positioning System (GPS) to achieve accurate positioning information and adapt those strategies that are appropriate to the design of the CATBox range determination system.

  19. Advance directives

    PubMed Central

    O’Sullivan, Rory; Mailo, Kevin; Angeles, Ricardo; Agarwal, Gina

    2015-01-01

    Abstract Objective To establish the prevalence of patients with advance directives in a family practice, and to describe patients’ perspectives on a family doctor’s role in initiating discussions about advance directives. Design A self-administered patient questionnaire. Setting A busy urban family medicine teaching clinic in Hamilton, Ont. Participants A convenience sample of adult patients attending the clinic over the course of a typical business week. Main outcome measures The prevalence of advance directives in the patient population was determined, and the patients’ expectations regarding the role of their family doctors were elucidated. Results The survey population consisted of 800 participants (a response rate of 72.5%) well distributed across age groups; 19.7% had written advance directives and 43.8% had previously discussed the topic of advance directives, but only 4.3% of these discussions had occurred with family doctors. In 5.7% of cases, a family physician had raised the issue; 72.3% of respondents believed patients should initiate the discussion. Patients who considered advance directives extremely important were significantly more likely to want their family doctors to start the conversation (odds ratio 3.98; P < .05). Conclusion Advance directives were not routinely addressed in the family practice. Most patients preferred to initiate the discussion of advance directives. However, patients who considered the subject extremely important wanted their family doctors to initiate the discussion. PMID:25873704

  20. Directing 101.

    ERIC Educational Resources Information Center

    Pintoff, Ernest

    Providing an introduction to anyone considering directing as a field of study or career, this book takes a broad look at the process of directing and encourages students and professionals alike to look outside of the movie industry for inspiration. Chapters in the book discuss selecting and acquiring material; budgeting and financing; casting and…

  1. Cvode component user guidelines.

    SciTech Connect

    Ray, Jaideep; Allan, Benjamin A.; Smith, Kylene J.

    2003-05-01

    This report describes the wrapping of cvode, a serial library of BDF-based solvers for stiff ODE systems, into a CCA component. It also gives examples of how one loads In the Cvode Component into the CCA framework, (Sandia's dccafe) as well as how the interface to the component (called CvodePort) is used. The report concludes with some timing results whereby we empirically show that componentization results in a maximum 2% performance degradation on a single CPU. The component can be obtained from Jaideep Ray (jairav@ca.sandia.gov, 925-294-3638)

  2. Long range global warming

    SciTech Connect

    Rolle, K.C.; Pulkrabek, W.W.; Fiedler, R.A.

    1995-12-31

    This paper explores one of the causes of global warming that is often overlooked, the direct heating of the environment by engineering systems. Most research and studies of global warming concentrate on the modification that is occurring to atmospheric air as a result of pollution gases being added by various systems; i.e., refrigerants, nitrogen oxides, ozone, hydrocarbons, halon, and others. This modification affects the thermal radiation balance between earth, sun and space, resulting in a decrease of radiation outflow and a slow rise in the earth`s steady state temperature. For this reason the solution to the problem is perceived as one of cleaning up the processes and effluents that are discharged into the environment. In this paper arguments are presented that suggest, that there is a far more serious cause for global warming that will manifest itself in the next two or three centuries; direct heating from the exponential growth of energy usage by humankind. Because this is a minor contributor to the global warming problem at present, it is overlooked or ignored. Energy use from the combustion of fuels and from the output of nuclear reactions eventually is manifest as warming of the surroundings. Thus, as energy is used at an ever increasing rate the consequent global warming also increases at an ever increasing rate. Eventually this rate will become equal to a few percent of solar radiation. When this happens the earth`s temperature will have risen by several degrees with catastrophic results. The trends in world energy use are reviewed and some mathematical models are presented to suggest future scenarios. These models can be used to predict when the global warming problem will become undeniably apparent, when it will become critical, and when it will become catastrophic.

  3. A comparative study of principal component analysis and independent component analysis in eddy current pulsed thermography data processing.

    PubMed

    Bai, Libing; Gao, Bin; Tian, Shulin; Cheng, Yuhua; Chen, Yifan; Tian, Gui Yun; Woo, W L

    2013-10-01

    Eddy Current Pulsed Thermography (ECPT), an emerging Non-Destructive Testing and Evaluation technique, has been applied for a wide range of materials. The lateral heat diffusion leads to decreasing of temperature contrast between defect and defect-free area. To enhance the flaw contrast, different statistical methods, such as Principal Component Analysis and Independent Component Analysis, have been proposed for thermography image sequences processing in recent years. However, there is lack of direct and detailed independent comparisons in both algorithm implementations. The aim of this article is to compare the two methods and to determine the optimized technique for flaw contrast enhancement in ECPT data. Verification experiments are conducted on artificial and thermal fatigue nature crack detection. PMID:24182145

  4. The 1990 direct support infrastructure

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The airport and cargo terminal were individually analyzed in depth as the principal direct infrastructure components having cross impacts with aircraft carrying cargo. Containerization was also addressed in depth as an infrastructure component since it categorically is linked with and cross impacted by the aircraft, the cargo terminal, the surface transport system, the shipper and consignee, and the actual cargo being moved.

  5. Range imaging laser radar

    DOEpatents

    Scott, Marion W.

    1990-01-01

    A laser source is operated continuously and modulated periodically (typicy sinusoidally). A receiver imposes another periodic modulation on the received optical signal, the modulated signal being detected by an array of detectors of the integrating type. Range to the target determined by measuring the phase shift of the intensity modulation on the received optical beam relative to a reference. The receiver comprises a photoemitter for converting the reflected, periodically modulated, return beam to an accordingly modulated electron stream. The electron stream is modulated by a local demodulation signal source and subsequently converted back to a photon stream by a detector. A charge coupled device (CCD) array then averages and samples the photon stream to provide an electrical signal in accordance with the photon stream.

  6. Range imaging laser radar

    DOEpatents

    Scott, M.W.

    1990-06-19

    A laser source is operated continuously and modulated periodically (typically sinusoidally). A receiver imposes another periodic modulation on the received optical signal, the modulated signal being detected by an array of detectors of the integrating type. Range to the target determined by measuring the phase shift of the intensity modulation on the received optical beam relative to a reference. The receiver comprises a photoemitter for converting the reflected, periodically modulated, return beam to an accordingly modulated electron stream. The electron stream is modulated by a local demodulation signal source and subsequently converted back to a photon stream by a detector. A charge coupled device (CCD) array then averages and samples the photon stream to provide an electrical signal in accordance with the photon stream. 2 figs.

  7. Strainrange partitioning: A total strain range version

    NASA Technical Reports Server (NTRS)

    Halford, G. R.; Saltsman, J. F.

    1983-01-01

    Procedures are presented for expressing the Strainrange Partitioning (SRP) method for creep fatigue life prediction in terms of total strain range. Inelastic and elastic strain-range - life relations are summed to give total strain-range - life relations. The life components due to inelastic strains are dealt with using conventional SRP procedures while the life components due to elastic strains are expressed as families of time-dependent terms for each type of SRP cycle. Cyclic constitutive material behavior plays an important role in establishing the elastic strain-range - life relations as well as the partitioning of the inelastic strains. To apply the approach, however, it is not necessary to have to determine the magnitude of the inelastic strain range. The total strain SRP approach is evaluated and verified using two nickel base superalloys, AF2-1DA and Rene 95. Excellent agreement is demonstrated between observed and predicted cyclic lifetimes with 70 to 80 percent of the predicted lives falling within factors of two of the observed lives. The total strain-range SRP approach should be of considerable practical value to designers who are faced with creep-fatigue problems for which the inelastic strains cannot be calculated with sufficient accuracy to make reliable life predictions by the conventional inelastic strain range SRP approach.

  8. Tropospheric range error parameters: Further studies

    NASA Technical Reports Server (NTRS)

    Hopfield, H. S.

    1972-01-01

    Improved parameters are presented for predicting the tropospheric effect on electromagnetic range measurements from surface meteorological data. Parameters are given for computing the dry component of the zenith radio range effect from surface pressure alone with an rms error of 1 to 2 mm, or the total range effect from the dry and wet components of the surface refractivity, N, and a two-part quartic profile model. The parameters were obtained from meteorological balloon data with improved procedures, including the conversion of the geopotential heights of the balloon data to actual or geometric heights before using the data. The revised values of the parameter k show more latitude variation than is accounted for by the variation of g. This excess variation of k indicates a small latitude variation in the mean molecular weight of air and yields information about the latitude-varying water vapor content of air.

  9. Generalized Structured Component Analysis

    ERIC Educational Resources Information Center

    Hwang, Heungsun; Takane, Yoshio

    2004-01-01

    We propose an alternative method to partial least squares for path analysis with components, called generalized structured component analysis. The proposed method replaces factors by exact linear combinations of observed variables. It employs a well-defined least squares criterion to estimate model parameters. As a result, the proposed method…

  10. Design of Critical Components

    NASA Technical Reports Server (NTRS)

    Hendricks, Robert C.; Zaretsky, Erwin V.

    2001-01-01

    Critical component design is based on minimizing product failures that results in loss of life. Potential catastrophic failures are reduced to secondary failures where components removed for cause or operating time in the system. Issues of liability and cost of component removal become of paramount importance. Deterministic design with factors of safety and probabilistic design address but lack the essential characteristics for the design of critical components. In deterministic design and fabrication there are heuristic rules and safety factors developed over time for large sets of structural/material components. These factors did not come without cost. Many designs failed and many rules (codes) have standing committees to oversee their proper usage and enforcement. In probabilistic design, not only are failures a given, the failures are calculated; an element of risk is assumed based on empirical failure data for large classes of component operations. Failure of a class of components can be predicted, yet one can not predict when a specific component will fail. The analogy is to the life insurance industry where very careful statistics are book-kept on classes of individuals. For a specific class, life span can be predicted within statistical limits, yet life-span of a specific element of that class can not be predicted.

  11. The Elusive Third Component

    NASA Technical Reports Server (NTRS)

    Meyers, James F.

    2004-01-01

    The historical development of techniques for measuring three velocity components using laser velocimetry is presented. The techniques are described and their relative merits presented. Many of the approaches currently in use based on the fringe laser velocimeter have yielded inaccurate measurements of turbulence intensity in the on-axis component. A possible explanation for these inaccuracies is presented along with simulation results.

  12. IRRIGATION SYSTEM COMPONENTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The common components of a irrigation system are defined in terms of the diversion, delivery, distribution and drainage subsystems. Irrigation systems can be defined on at least three different levels: project, farm and field. Each level will have the same basic set of components regardless of sca...

  13. Structure and compositional studies of multi-component nanoparticles

    NASA Astrophysics Data System (ADS)

    Malyavanatham, Gokul

    The laser ablation of microparticle (LAM) process was used to study nanoparticles of multi-component materials. The production process utilized laser ablation of a continuously flowing aerosol of micron-sized particles under a gas ambient. An aerosol generator entrained microparticles into a gas flow and directed them through a nozzle into a laser interaction cell. After plasma breakdown, the shock wave propagated through the microparticles and the nanoparticles condensed behind this shockwave. Two methods were developed to collect nanoparticles; the first method used supersonic impaction on substrates at room temperature to enable direct writing of thick films and the second method used electric fields to deflect and collect charged, individual nanoparticles. Two methods for generating multi-component nanostructured materials were studied. The first method involved feeding single-phase microparticles containing the desired composition. Lead Zirconate Titanate (PZT) microparticles were used to generate nanoparticles that were then impacted onto substrates to produce thick films. Quality, morphology, crystallization and composition variations of these thick films were analyzed using material characterization techniques. Segregation of elements and an overall deficiency in Zr and Ti were observed in the deposited thick films as a result of the agglomerated state of the PZT microparticles. However, the analysis for this material system was complicated by the presence of multiple compounds. To develop a further understanding of how segregation occurs in multi-component systems during the LAM process, a second method for generating multi-component nanoparticles by feeding mixtures of single component microparticles was studied. Nanoparticles generated by ablation of Cu and Au microparticle mixtures were collected electrostatically and analyzed. Interactions between exploding microparticles resulted in condensation of nanoparticles that were non-equilibrium solid

  14. Paleomagnetism of Jurassic radiolarian chert above the Coast Range ophiolite at Stanley Mountain, California, and implications for its paleogeographic origins

    USGS Publications Warehouse

    Hagstrum, J.T.; Murchey, B.L.

    1996-01-01

    Upper Jurassic red tuffaceous chert above the Coast Range ophiolite at Stanley Mountain, California (lat 35??N, long 240??E), contains three components of remanent magnetization. The first component (A; removed by ???100-???200 ??C) has a direction near the present-day field for southern California and is probably a recently acquired thermoviscous magnetization. A second component (B; removed between ???100 and ???600 ??C) is identical to that observed by previous workers in samples of underlying pillow basalt and overlying terrigenous sedimentary rocks. This component has constant normal polarity and direction throughout the entire section, although these rocks were deposited during a mixed polarity interval of the geomagnetic field. The B magnetization, therefore, is inferred to be a secondary magnetization acquired during accretion, uplift, or Miocene volcanism prior to regional clockwise rotation. The highest temperature component (C; removed between ???480 and 680 ??C) is of dual polarity and is tentatively interpreted as a primary magnetization, although it fails a reversal test possibly due to contamination by B. Separation of the B and C components is best shown by samples with negative-inclination C directions, and a corrected mean direction using only these samples indicates an initial paleolatitude of 32??N ?? 8??. Paleobiogeographic models relating radiolarian faunal distribution patterns to paleolatitude have apparently been incorrectly calibrated using the overprint B component. Few other paleomagnetic data have been incorporated in these models, and faunal distribution patterns are poorly known and mostly unqualified. The available data, therefore, do not support formation of the Coast Range ophiolite at Stanley Mountain near the paleoequator or accretion at ???10??N paleolatitude, as has been previously suggested based on paleomagnetic data, but indicate deposition near expected paleolatitudes for North America (35??N ?? 4??) during Late Jurassic

  15. Measurement of thermal contact conductance of SPring-8 beamline components

    NASA Astrophysics Data System (ADS)

    Mochizuki, Tetsuro; Ohashi, Haruhiko; Sano, Mutsumi; Takahashi, Sunao; Goto, Shunji

    2007-09-01

    Direct cooling is adopted for most high heat load components in SPring-8 beamlines. On the other hand, contact cooling is employed for some components such as a graphite filter, aluminum filter, mirror, and cryogenic monochromator silicon crystal. For the thermal design of the contact cooling components, it is important to obtain reliable thermal contact conductance value. The conductance depends on many parameters such as the surface materials, surface roughness, flatness of the surface, interstitial materials, temperature of the contact surface, and contact pressure. An experimental setup is fablicated to measure the conductance at liquid nitrogen temperature and room temperature. The thermal contact conductance of a Si-Cu interface and that of a Si-In-Cu interface are measured at cryogenic temperature at contact pressures ranging from 0.1-1.1 MPa. The conductance of an Al-Cu interface and that of a graphite-Cu interface are measured using gold and silver foils as interstitial materials. The measurements are performed at room temperature and at pressures ranging from 0.5-4 MPa. The experimental setup and the results obtained are presented.

  16. Neutron range spectrometer

    DOEpatents

    Manglos, Stephen H.

    1989-06-06

    A neutron range spectrometer and method for determining the neutron energy spectrum of a neutron emitting source are disclosed. Neutrons from the source are collimnated along a collimation axis and a position sensitive neutron counter is disposed in the path of the collimated neutron beam. The counter determines positions along the collimation axis of interactions between the neutrons in the neutron beam and a neutron-absorbing material in the counter. From the interaction positions, a computer analyzes the data and determines the neutron energy spectrum of the neutron beam. The counter is preferably shielded and a suitable neutron-absorbing material is He-3. The computer solves the following equation in the analysis: ##EQU1## where: N(x).DELTA.x=the number of neutron interactions measured between a position x and x+.DELTA.x, A.sub.i (E.sub.i).DELTA.E.sub.i =the number of incident neutrons with energy between E.sub.i and E.sub.i +.DELTA.E.sub.i, and C=C(E.sub.i)=N .sigma.(E.sub.i) where N=the number density of absorbing atoms in the position sensitive counter means and .sigma. (E.sub.i)=the average cross section of the absorbing interaction between E.sub.i and E.sub.i +.DELTA.E.sub.i.

  17. Method for directional hydraulic fracturing

    DOEpatents

    Swanson, David E.; Daly, Daniel W.

    1994-01-01

    A method for directional hydraulic fracturing using borehole seals to confine pressurized fluid in planar permeable regions, comprising: placing a sealant in the hole of a structure selected from geologic or cemented formations to fill the space between a permeable planar component and the geologic or cemented formation in the vicinity of the permeable planar component; making a hydraulic connection between the permeable planar component and a pump; permitting the sealant to cure and thereby provide both mechanical and hydraulic confinement to the permeable planar component; and pumping a fluid from the pump into the permeable planar component to internally pressurize the permeable planar component to initiate a fracture in the formation, the fracture being disposed in the same orientation as the permeable planar component.

  18. Multi-target compressive laser ranging

    NASA Astrophysics Data System (ADS)

    Pandit, Pushkar P.; Dahl, Jason R.; Barber, Zeb W.; Babbitt, W. Randall

    2014-05-01

    Compressive laser ranging (CLR) is a method that exploits the sparsity available in the range domain using compressive sensing methods to directly obtain range domain information. Conventional ranging methods are marred by requirements of high bandwidth analog detection which includes severe SNR fall off with bandwidth in analog-to-digital conversion (ADC). Compressive laser ranging solves this problem by obtaining sub-centimeter resolution while using low bandwidth detection. High rate digital pulse pattern generators and off the shelf photonic devices are used to modulate the transmitted and received light from a superluminescent diode. CLR detection is demonstrated using low bandwidth, high dynamic range detectors along with photon counting techniques. The use of an incoherent source eliminates speckle issues and enables simplified CLR methods to get multi-target range profiles with 1-3cm resolution. Using compressive sensing methods CLR allows direct range measurements in the sub-Nyquist regime while reducing system resources, in particular the need for high bandwidth ADC.

  19. GCS component development cycle

    NASA Astrophysics Data System (ADS)

    Rodríguez, Jose A.; Macias, Rosa; Molgo, Jordi; Guerra, Dailos; Pi, Marti

    2012-09-01

    The GTC1 is an optical-infrared 10-meter segmented mirror telescope at the ORM observatory in Canary Islands (Spain). First light was at 13/07/2007 and since them it is in the operation phase. The GTC control system (GCS) is a distributed object & component oriented system based on RT-CORBA8 and it is responsible for the management and operation of the telescope, including its instrumentation. GCS has used the Rational Unified process (RUP9) in its development. RUP is an iterative software development process framework. After analysing (use cases) and designing (UML10) any of GCS subsystems, an initial component description of its interface is obtained and from that information a component specification is written. In order to improve the code productivity, GCS has adopted the code generation to transform this component specification into the skeleton of component classes based on a software framework, called Device Component Framework. Using the GCS development tools, based on javadoc and gcc, in only one step, the component is generated, compiled and deployed to be tested for the first time through our GUI inspector. The main advantages of this approach are the following: It reduces the learning curve of new developers and the development error rate, allows a systematic use of design patterns in the development and software reuse, speeds up the deliverables of the software product and massively increase the timescale, design consistency and design quality, and eliminates the future refactoring process required for the code.

  20. Component-specific modeling

    NASA Technical Reports Server (NTRS)

    Hirschbein, M. S.

    1982-01-01

    The ability to accurately structurally analyze engine components to assure that they can survive for their designed lifetime in an increasingly harsh environment is discussed. Under the HOST (HOt Section Technology) program, advanced component-specific modeling methods, with built-in analysis capability, will be developed separately for burner liners, turbine blades and vanes. These modeling methods will make maximum use of, but will not rely solely on, existing analysis methods and techniques, to analyze the three identified components. Nor will the complete structural analysis of a component necessarily be performed as a single analysis. The approach to be taken will develop complete software analysis packages with internal, component-specific, self-adaptive solution strategies. Each package will contain a set of modeling and analysis tools. The selection and order of specific methods and techniques within the set to be applied will depend on the specific-component, the current thermo-mechanical loading, and the current state of the component. All modeling and analysis decisions will be made internally based on developed decision criteria within the solution strategies; minimal user intervention will be required.

  1. Discriminant Incoherent Component Analysis.

    PubMed

    Georgakis, Christos; Panagakis, Yannis; Pantic, Maja

    2016-05-01

    Face images convey rich information which can be perceived as a superposition of low-complexity components associated with attributes, such as facial identity, expressions, and activation of facial action units (AUs). For instance, low-rank components characterizing neutral facial images are associated with identity, while sparse components capturing non-rigid deformations occurring in certain face regions reveal expressions and AU activations. In this paper, the discriminant incoherent component analysis (DICA) is proposed in order to extract low-complexity components, corresponding to facial attributes, which are mutually incoherent among different classes (e.g., identity, expression, and AU activation) from training data, even in the presence of gross sparse errors. To this end, a suitable optimization problem, involving the minimization of nuclear-and l1 -norm, is solved. Having found an ensemble of class-specific incoherent components by the DICA, an unseen (test) image is expressed as a group-sparse linear combination of these components, where the non-zero coefficients reveal the class(es) of the respective facial attribute(s) that it belongs to. The performance of the DICA is experimentally assessed on both synthetic and real-world data. Emphasis is placed on face analysis tasks, namely, joint face and expression recognition, face recognition under varying percentages of training data corruption, subject-independent expression recognition, and AU detection by conducting experiments on four data sets. The proposed method outperforms all the methods that are compared with all the tasks and experimental settings. PMID:27008268

  2. Difference-NMR techniques for selection of components on the basis of relaxation times

    NASA Astrophysics Data System (ADS)

    Harris, Douglas J.; de Azevedo, Eduardo R.; Bonagamba, Tito J.

    2003-05-01

    This work describes a numerical methodology to obtain more efficient relaxation filters to selectively retain or remove components based on relaxation times. The procedure uses linear combinations of spectra with various recycle or filter delays to obtain components that are both quantitative and pure. Modulation profiles are calculated assuming exponential relaxation behavior. The method is general and can be applied to a wide range of solution or solid-state NMR experiments including direct-polarization (DP), or filtered cross-polarization (CP) spectra. 13C NMR experiments on isotactic poly(1-butene) and dimethyl sulfone showed the utility of the technique for selectively suppressing peaks.

  3. Synovial sarcoma specific translocation associated with both epithelial and spindle cell components.

    PubMed

    Birdsall, S; Osin, P; Lu, Y J; Fisher, C; Shipley, J

    1999-08-12

    The biphasic subtype of synovial sarcoma consists of both epithelial and spindle cell components. To address the relationship between the different cellular components found in synovial sarcoma, we deduced the presence of the synovial sarcoma-specific der(X)t(X;18)(p11.2;q11.2), and involvement of the SSX1 gene in both the epithelial/glandular and spindle cell components of 3 biphasic synovial sarcomas with wide ranging proportions of each of the 2 elements. This has been achieved using a 2-color fluorescence in situ hybridization (FISH) methodology that we had developed recently for analysis paraffin-embedded material. The presence of the rearrangement could be deduced in histologically defined regions and the results showed clearly that the rearrangement was present in both cellular components. This finding provides direct genetic evidence for biphasic synovial sarcomas being clonal and truly biphasic. PMID:10404078

  4. Component-specific modeling

    NASA Technical Reports Server (NTRS)

    Mcknight, R. L.

    1985-01-01

    Accomplishments are described for the second year effort of a 3-year program to develop methodology for component specific modeling of aircraft engine hot section components (turbine blades, turbine vanes, and burner liners). These accomplishments include: (1) engine thermodynamic and mission models; (2) geometry model generators; (3) remeshing; (4) specialty 3-D inelastic stuctural analysis; (5) computationally efficient solvers, (6) adaptive solution strategies; (7) engine performance parameters/component response variables decomposition and synthesis; (8) integrated software architecture and development, and (9) validation cases for software developed.

  5. Ceramic component for electrodes

    DOEpatents

    Marchant, David D.

    1979-01-01

    A ceramic component suitable for preparing MHD generator electrodes consists of HfO.sub.2 and sufficient Tb.sub.4 O.sub.7 to stabilize at least 60 volume percent of the HfO.sub.2 into the cubic structure. The ceramic component may also contain a small amount of PrO.sub.2, Yb.sub.2 O.sub.3 or a mixture of both to improve stability and electronic conductivity of the electrode. The component is highly resistant to corrosion by molten potassium seed and molten coal slag in the MHD fluid and exhibits both ionic and electronic conductivity.

  6. Contribution of laser ranging to Earth's sciences

    NASA Astrophysics Data System (ADS)

    Exertier, Pierre; Bonnefond, Pascal; Deleflie, Florent; Barlier, François; Kasser, Michel; Biancale, Richard; Ménard, Yves

    2006-11-01

    Satellite and Lunar Laser Ranging (SLR and LLR, respectively) are based on a direct measurement of a distance by exactly measuring the time transit of a laser beam between a station and a space target. These techniques have proven to be very efficient methods for contributing to the tracking of both artificial satellites and the Moon, and for determining accurately their orbit and the associated geodynamical parameters, although hampered by the non-worldwide coverage and the meteorological conditions. Since more than 40 years, the French community (today 'Observatoire de la Côte d'Azur', CNES, 'Observatoire de Paris', and IGN) is largely involved in the technological developments as well as in the scientific achievements. The role of the laser technique has greatly evolved thanks to the success of GPS and DORIS; the laser technique teams have learnt to focus their effort in fields where this technique is totally specific and irreplaceable. The role of SLR data in the determination of terrestrial reference systems and in the modelling of the first terms of the gravity field (including the terrestrial constant GM that defines the scale of orbits) has to be emphasized, which is of primary importance in orbitography, whatever the tracking technique used. In addition, the role of LLR data (with two main stations, at Mac Donald (United States) and Grasse (France), since 30 years) has been of particular importance for improving solar system ephemeris and contributing to some features of fundamental physics (equivalence principle). Today, the role of the SLR technique is ( i) to determine and to maintain the scale factor of the global terrestrial reference frame, ( ii) to strengthen the vertical component (including velocity) of the positioning, which is crucial for altimetry missions and tectonic motions, ( iii) to locate the geocenter with respect to the Earth's crust, ( iv) to avoid any secular and undesirable drift of geodetic systems thanks to a very good accuracy

  7. Bi-Directional DC-DC Converter for PHEV Applications

    SciTech Connect

    Abas Goodarzi

    2011-01-31

    Plug-In Hybrid Electric Vehicles (PHEV) require high power density energy storage system (ESS) for hybrid operation and high energy density ESS for Electric Vehicle (EV) mode range. However, ESS technologies to maximize power density and energy density simultaneously are not commercially feasible. The use of bi-directional DC-DC converter allows use of multiple energy storage, and the flexible DC-link voltages can enhance the system efficiency and reduce component sizing. This will improve fuel consumption, increase the EV mode range, reduce the total weight, reduce battery initial and life cycle cost, and provide flexibility in system design.

  8. Tracking Honey Bees Using LIDAR (Light Detection and Ranging) Technology

    SciTech Connect

    BENDER, SUSAN FAE ANN; RODACY, PHILIP J.; SCHMITT, RANDAL L.; HARGIS JR., PHILIP J.; JOHNSON, MARK S.; KLARKOWSKI, JAMES R.; MAGEE, GLEN I.; BENDER, GARY LEE

    2003-01-01

    The Defense Advanced Research Projects Agency (DARPA) has recognized that biological and chemical toxins are a real and growing threat to troops, civilians, and the ecosystem. The Explosives Components Facility at Sandia National Laboratories (SNL) has been working with the University of Montana, the Southwest Research Institute, and other agencies to evaluate the feasibility of directing honeybees to specific targets, and for environmental sampling of biological and chemical ''agents of harm''. Recent work has focused on finding and locating buried landmines and unexploded ordnance (UXO). Tests have demonstrated that honeybees can be trained to efficiently and accurately locate explosive signatures in the environment. However, it is difficult to visually track the bees and determine precisely where the targets are located. Video equipment is not practical due to its limited resolution and range. In addition, it is often unsafe to install such equipment in a field. A technology is needed to provide investigators with the standoff capability to track bees and accurately map the location of the suspected targets. This report documents Light Detection and Ranging (LIDAR) tests that were performed by SNL. These tests have shown that a LIDAR system can be used to track honeybees. The LIDAR system can provide both the range and coordinates of the target so that the location of buried munitions can be accurately mapped for subsequent removal.

  9. Structural materials and components

    NASA Technical Reports Server (NTRS)

    Gagliani, John (Inventor); Lee, Raymond (Inventor)

    1982-01-01

    High density structural (blocking) materials composed of a polyimide filled with glass microballoons. Structural components such as panels which have integral edgings and/or other parts made of the high density materials.

  10. Structural materials and components

    NASA Technical Reports Server (NTRS)

    Gagliani, John (Inventor); Lee, Raymond (Inventor)

    1982-01-01

    High density structural (blocking) materials composed of a polyimide filled with glass microballoons and methods for making such materials. Structural components such as panels which have integral edgings and/or other parts made of the high density materials.

  11. Component Fixturing Method

    NASA Technical Reports Server (NTRS)

    Kling, Daniel (Inventor)

    2014-01-01

    An end-configuration of components to be moved or positioned is first obtained. This end-configuration determines the relative positioning and orientation of the components with respect to each other when in a final, desired configuration. A folding pattern is then obtained that is formed by interior vertices defining corresponding tessellation facets. The folding pattern can be induced to transition from a first folded configuration to a second folded configuration. When in the second folded configuration mounting facets, which are a subset of the tessellation facets, are arranged by the geometry of the folding pattern into positions and orientations with respect to each other that correspond to the end-configuration of the components. A foldable structure is then obtained that folds in accordance with the folding pattern, and the components are affixed to their respective mounting facets.

  12. Structural materials and components

    NASA Technical Reports Server (NTRS)

    Gagliani, John (Inventor); Lee, Raymond (Inventor)

    1983-01-01

    High density structural (blocking) materials composed of a polyimide filled with glass microballoons. Structural components such as panels which have integral edgings and/or other parts made of the high density materials.

  13. Accuracy analysis of optical ranging in atmosphere

    NASA Astrophysics Data System (ADS)

    Yuan, Hong-wu; Huang, Yin-bo; Mei, Hai-ping; Rao, Rui-zhong

    2009-07-01

    Optical ranging is one of the most precise techniques for distance measurement. The effects of the density variation of atmosphere, aerosols and clouds on optical ranging precision are generally considered, a new method is proposed for calculating the ranging precision in the presence of aerosol particles and clouds. The size distribution spectrum models for aerosols and clouds in the Optical Properties of Aerosols and Clouds Package (OPAC) are adopted. Results show that aerosols and clouds could introduce errors of several centimeters to several ten meters to the ranging. The relationship between the ranging precision and the relative humidity, the zenith angle of ranging direction and the optical wavelength is also analyzed. The ranging error doesn't have an obvious relationship with the wavelength, but depends on the zenith angle, especially for the angle larger than 70 degree. The ranging error depends on the relative humidity as well. The ranging error induced by aerosols increases gradually with the increase of the relative humidity when the relative humidity is less than 80%, but it increases rapidly when the relative humidity is larger than 80%. Our results could provide a theoretical basis and reference for the application of optical ranging.

  14. Collective fluctuations in networks of noisy components

    NASA Astrophysics Data System (ADS)

    Masuda, Naoki; Kawamura, Yoji; Kori, Hiroshi

    2010-09-01

    Collective dynamics result from interactions among noisy dynamical components. Examples include heartbeats, circadian rhythms and various pattern formations. Because of noise in each component, collective dynamics inevitably involve fluctuations, which may crucially affect the functioning of the system. However, the relation between the fluctuations in isolated individual components and those in collective dynamics is not clear. Here, we study a linear dynamical system of networked components subjected to independent Gaussian noise and analytically show that the connectivity of networks determines the intensity of fluctuations in the collective dynamics. Remarkably, in general directed networks including scale-free networks, the fluctuations decrease more slowly with system size than the standard law stated by the central limit theorem. They even remain finite for a large system size when global directionality of the network exists. Moreover, such non-trivial behavior appears even in undirected networks when nonlinear dynamical systems are considered. We demonstrate it with a coupled oscillator system.

  15. Develop a Model Component

    NASA Technical Reports Server (NTRS)

    Ensey, Tyler S.

    2013-01-01

    During my internship at NASA, I was a model developer for Ground Support Equipment (GSE). The purpose of a model developer is to develop and unit test model component libraries (fluid, electrical, gas, etc.). The models are designed to simulate software for GSE (Ground Special Power, Crew Access Arm, Cryo, Fire and Leak Detection System, Environmental Control System (ECS), etc. .) before they are implemented into hardware. These models support verifying local control and remote software for End-Item Software Under Test (SUT). The model simulates the physical behavior (function, state, limits and 110) of each end-item and it's dependencies as defined in the Subsystem Interface Table, Software Requirements & Design Specification (SRDS), Ground Integrated Schematic (GIS), and System Mechanical Schematic.(SMS). The software of each specific model component is simulated through MATLAB's Simulink program. The intensiv model development life cycle is a.s follows: Identify source documents; identify model scope; update schedule; preliminary design review; develop model requirements; update model.. scope; update schedule; detailed design review; create/modify library component; implement library components reference; implement subsystem components; develop a test script; run the test script; develop users guide; send model out for peer review; the model is sent out for verifictionlvalidation; if there is empirical data, a validation data package is generated; if there is not empirical data, a verification package is generated; the test results are then reviewed; and finally, the user. requests accreditation, and a statement of accreditation is prepared. Once each component model is reviewed and approved, they are intertwined together into one integrated model. This integrated model is then tested itself, through a test script and autotest, so that it can be concluded that all models work conjointly, for a single purpose. The component I was assigned, specifically, was a

  16. Component fragility research program

    SciTech Connect

    Tsai, N.C.; Mochizuki, G.L.; Holman, G.S.; Lawrence Livermore National Lab., CA )

    1989-11-01

    To demonstrate how high-level'' qualification test data can be used to estimate the ultimate seismic capacity of nuclear power plant equipment, we assessed in detail various electrical components tested by the Pacific Gas Electric Company for its Diablo Canyon plant. As part of our Phase I Component Fragility Research Program, we evaluated seismic fragility for five Diablo Canyon components: medium-voltage (4kV) switchgear; safeguard relay board; emergency light battery pack; potential transformer; and station battery and racks. This report discusses our Phase II fragility evaluation of a single Westinghouse Type W motor control center column, a fan cooler motor controller, and three local starters at the Diablo Canyon nuclear power plant. These components were seismically qualified by means of biaxial random motion tests on a shaker table, and the test response spectra formed the basis for the estimate of the seismic capacity of the components. The seismic capacity of each component is referenced to the zero period acceleration (ZPA) and, in our Phase II study only, to the average spectral acceleration (ASA) of the motion at its base. For the motor control center, the seismic capacity was compared to the capacity of a Westinghouse Five-Star MCC subjected to actual fragility tests by LLNL during the Phase I Component Fragility Research Program, and to generic capacities developed by the Brookhaven National Laboratory for motor control center. Except for the medium-voltage switchgear, all of the components considered in both our Phase I and Phase II evaluations were qualified in their standard commercial configurations or with only relatively minor modifications such as top bracing of cabinets. 8 refs., 67 figs., 7 tabs.

  17. Feasibility of producing a range of food products from a limited range of undifferenitiated major food components

    NASA Technical Reports Server (NTRS)

    Karel, M.; Kamarei, A. R.

    1984-01-01

    This report reviews current knowledge associated with producing safe, nutritious, and acceptable foods from a limited number of source independent macronutrients. The advantages, and disadvantages, of such an approach for use by space crews are discussed. The production of macronutrients from a variety of sources is covered in detail. The sources analyzed are: wheat, soybeans, algae (3 genera), glycerol, and digested cellulose. Fabrication of food from the above macronutrient sources is discussed and particular attention is addressed to nutrition, acceptability and reliability. The processes and concepts involved in food fabrication and macronutrient production are also considered for utilization in a space environment.

  18. Household Health Costs: Direct, Indirect and Intangible

    PubMed Central

    YOUSEFI, Mehdi; ASSARI ARANI, Abbas; SAHABI, Bahram; KAZEMNEJAD, Anoshirvan; FAZAELI, Somayeh

    2014-01-01

    Abstract Background This study aimed at identifying components of the household health costs. Methods This study was a qualitative research conducted in two main phases. The first phase consisted of interviews with sample households selected in eight provinces of Iran. They were to identify components of the household health costs. In the second phase, components were determined as direct, indirect and intangible based on a content analysis. Results In the first phase of the study, 93 components of households’ health costs were identified. According to the content analysis, 44 components were categorized as direct costs, 10 components were indirect and 39 components were categorized as intangible. Conclusion All components of households’ health costs including: direct, indirect and intangible costs, should be considered in the planning and policy-making in the health system. PMID:26060744

  19. Wide temperature range seal for demountable joints

    DOEpatents

    Sixsmith, Herbert; Valenzuela, Javier A.; Nutt, William E.

    1991-07-23

    The present invention is directed to a seal for demountable joints operating over a wide temperature range down to liquid helium temperatures. The seal has anti-extrusion guards which prevent extrusion of the soft ductile sealant material, which may be indium or an alloy thereof.

  20. Compact range for variable-zone measurements

    DOEpatents

    Burnside, Walter D.; Rudduck, Roger C.; Yu, Jiunn S.

    1988-01-01

    A compact range for testing antennas or radar targets includes a source for directing energy along a feedline toward a parabolic reflector. The reflected wave is a spherical wave with a radius dependent on the distance of the source from the focal point of the reflector.

  1. Compact range for variable-zone measurements

    DOEpatents

    Burnside, W.D.; Rudduck, R.C.; Yu, J.S.

    1987-02-27

    A compact range for testing antennas or radar targets includes a source for directing energy along a feedline toward a parabolic reflector. The reflected wave is a spherical wave with a radius dependent on the distance of the source from the focal point of the reflector. 2 figs.

  2. Wide temperature range seal for demountable joints

    DOEpatents

    Sixsmith, H.; Valenzuela, J.A.; Nutt, W.E.

    1991-07-23

    The present invention is directed to a seal for demountable joints operating over a wide temperature range down to liquid helium temperatures. The seal has anti-extrusion guards which prevent extrusion of the soft ductile sealant material, which may be indium or an alloy thereof. 6 figures.

  3. Compact range for variable-zone measurements

    DOEpatents

    Burnside, Walter D.; Rudduck, Roger C.; Yu, Jiunn S.

    1988-08-02

    A compact range for testing antennas or radar targets includes a source for directing energy along a feedline toward a parabolic reflector. The reflected wave is a spherical wave with a radius dependent on the distance of the source from the focal point of the reflector.

  4. Expansion-based passive ranging

    NASA Technical Reports Server (NTRS)

    Barniv, Yair

    1993-01-01

    A new technique of passive ranging which is based on utilizing the image-plane expansion experienced by every object as its distance from the sensor decreases is described. This technique belongs in the feature/object-based family. The motion and shape of a small window, assumed to be fully contained inside the boundaries of some object, is approximated by an affine transformation. The parameters of the transformation matrix are derived by initially comparing successive images, and progressively increasing the image time separation so as to achieve much larger triangulation baseline than currently possible. Depth is directly derived from the expansion part of the transformation. To a first approximation, image-plane expansion is independent of image-plane location with respect to the focus of expansion (FOE) and of platform maneuvers. Thus, an expansion-based method has the potential of providing a reliable range in the difficult image area around the FOE. In areas far from the FOE the shift parameters of the affine transformation can provide more accurate depth information than the expansion alone, and can thus be used similarly to the way they were used in conjunction with the Inertial Navigation Unit (INU) and Kalman filtering. However, the performance of a shift-based algorithm, when the shifts are derived from the affine transformation, would be much improved compared to current algorithms because the shifts - as well as the other parameters - can be obtained between widely separated images. Thus, the main advantage of this new approach is that, allowing the tracked window to expand and rotate, in addition to moving laterally, enables one to correlate images over a very long time span which, in turn, translates into a large spatial baseline - resulting in a proportionately higher depth accuracy.

  5. Expansion-based passive ranging

    NASA Technical Reports Server (NTRS)

    Barniv, Yair

    1993-01-01

    This paper describes a new technique of passive ranging which is based on utilizing the image-plane expansion experienced by every object as its distance from the sensor decreases. This technique belongs in the feature/object-based family. The motion and shape of a small window, assumed to be fully contained inside the boundaries of some object, is approximated by an affine transformation. The parameters of the transformation matrix are derived by initially comparing successive images, and progressively increasing the image time separation so as to achieve much larger triangulation baseline than currently possible. Depth is directly derived from the expansion part of the transformation. To a first approximation, image-plane expansion is independent of image-plane location with respect to the focus of expansion (FOE) and of platform maneuvers. Thus, an expansion-based method has the potential of providing a reliable range in the difficult image area around the FOE. In areas far from the FOE the shift parameters of the affine transformation can provide more accurate depth information than the expansion alone, and can thus be used similarly to the way they have been used in conjunction with the Inertial Navigation Unit (INU) and Kalman filtering. However, the performance of a shift-based algorithm, when the shifts are derived from the affine transformation, would be much improved compared to current algorithms because the shifts--as well as the other parameters--can be obtained between widely separated images. Thus, the main advantage of this new approach is that, allowing the tracked window to expand and rotate, in addition to moving laterally, enables one to correlate images over a very long time span which, in turn, translates into a large spatial baseline resulting in a proportionately higher depth accuracy.

  6. Reference Ranges & What They Mean

    MedlinePlus

    ... be limited. Home Visit Global Sites Search Help? Reference Ranges and What They Mean Share this page: Was this page helpful? Overview | Reference range defined | Where are the reference ranges? | Limits ...

  7. NASTRAN component-mode synthesis

    NASA Technical Reports Server (NTRS)

    Guyan, R. J.

    1976-01-01

    Procedure for dynamic substructuring analysis technique is generally as follows: calculation of component modes; selection of component normal modes, calculation of component generalized matrices, assembly of system matrices, and computation of normal modes; and retrieval of component response.

  8. Emotional stability components of human performance problems

    SciTech Connect

    Wexler, R.H.

    1987-01-01

    Over half of all significant events that occur in nuclear plants involve human performance problems. There is increasing worldwide recognition that human performance problems have a significant impact on the safety, cost, and efficiency of nuclear plant operations. Emotional stability components have an important direct and indirect impact on human performance problems. This paper examines emotional stability components that are currently incorporated into human performance evaluation systems (HPES) in nuclear plants. It describes HPES programs being developed around the world, the emotional stability components that are currently referred to in these programs, and suggestions for improving HPES programs through a greater understanding of emotion stability components. A review of emotional stability components that may hinder or promote a plant environment that encourages the voluntary reporting and correction of human error is also presented.

  9. Encyclopedia of Software Components

    NASA Technical Reports Server (NTRS)

    Warren, Lloyd V. (Inventor); Beckman, Brian C. (Inventor)

    1997-01-01

    Intelligent browsing through a collection of reusable software components is facilitated with a computer having a video monitor and a user input interface such as a keyboard or a mouse for transmitting user selections, by presenting a picture of encyclopedia volumes with respective visible labels referring to types of software, in accordance with a metaphor in which each volume includes a page having a list of general topics under the software type of the volume and pages having lists of software components for each one of the generic topics, altering the picture to open one of the volumes in response to an initial user selection specifying the one volume to display on the monitor a picture of the page thereof having the list of general topics and altering the picture to display the page thereof having a list of software components under one of the general topics in response to a next user selection specifying the one general topic, and then presenting a picture of a set of different informative plates depicting different types of information about one of the software components in response to a further user selection specifying the one component.

  10. Scientific Component Technology Initiative

    SciTech Connect

    Kohn, S; Bosl, B; Dahlgren, T; Kumfert, G; Smith, S

    2003-02-07

    The laboratory has invested a significant amount of resources towards the development of high-performance scientific simulation software, including numerical libraries, visualization, steering, software frameworks, and physics packages. Unfortunately, because this software was not designed for interoperability and re-use, it is often difficult to share these sophisticated software packages among applications due to differences in implementation language, programming style, or calling interfaces. This LDRD Strategic Initiative investigated and developed software component technology for high-performance parallel scientific computing to address problems of complexity, re-use, and interoperability for laboratory software. Component technology is an extension of scripting and object-oriented software development techniques that specifically focuses on the needs of software interoperability. Component approaches based on CORBA, COM, and Java technologies are widely used in industry; however, they do not support massively parallel applications in science and engineering. Our research focused on the unique requirements of scientific computing on ASCI-class machines, such as fast in-process connections among components, language interoperability for scientific languages, and data distribution support for massively parallel SPMD components.

  11. Encyclopedia of software components

    NASA Technical Reports Server (NTRS)

    Vanwarren, Lloyd (Inventor); Beckman, Brian C. (Inventor)

    1991-01-01

    Intelligent browsing through a collection of reusable software components is facilitated with a computer having a video monitor and a user input interface such as a keyboard or a mouse for transmitting user selections, by presenting a picture of encyclopedia volumes with respective visible labels referring to types of software, in accordance with a metaphor in which each volume includes a page having a list of general topics under the software type of the volume and pages having lists of software components for each one of the generic topics, altering the picture to open one of the volumes in response to an initial user selection specifying the one volume to display on the monitor a picture of the page thereof having the list of general topics and altering the picture to display the page thereof having a list of software components under one of the general topics in response to a next user selection specifying the one general topic, and then presenting a picture of a set of different informative plates depicting different types of information about one of the software components in response to a further user selection specifying the one component.

  12. RDCDS Meteorologoical Component Quick Installation Guide

    SciTech Connect

    Berg, Larry K.; Pekour, Mikhail S.

    2007-11-20

    This guide provides step-by-step instructions for the deployment of one of the Rapidly Deployable Chemical Defense System (RDCDS) weather stations and central control system. Instructions for the deployment and operation of the Atmospheric Systems Corporation miniSODAR™ (SOnic Detection and Ranging) can be found in accompanying manuals developed by Atmospheric Systems Corporation. A detailed description of the system and its components can be found in the manual entitled Description of the RDCDS Meteorological Component.

  13. Behavioral components of impulsivity.

    PubMed

    Stahl, Christoph; Voss, Andreas; Schmitz, Florian; Nuszbaum, Mandy; Tüscher, Oliver; Lieb, Klaus; Klauer, Karl Christoph

    2014-04-01

    Acting in accord with long-term goals requires control of interfering impulses, the success of which depends on several different processes. Using a structural-equation modeling approach, we investigated 5 behavioral components of impulsivity: the control of stimulus interference, proactive interference, and response interference, as well as decisional and motivational impulsivity. Results support the existence of 5 correlated but separable components of impulsive behavior. The present study is the 1st to demonstrate the separability of stimulus and response interference. It also supports the notion that control of response-related interference is not a unitary construct: Response-selection demands were separable from those of withholding or stopping. Relations between behavioral impulsivity components and self-report measures of impulsivity were largely absent. We conclude that as the construct of impulsivity has been extended to describe an increasingly diverse set of phenomena and processes, it has become too broad to be helpful in guiding future research. PMID:23957282

  14. Component costs of foodborne illness: a scoping review

    PubMed Central

    2014-01-01

    Background Governments require high-quality scientific evidence to prioritize resource allocation and the cost-of-illness (COI) methodology is one technique used to estimate the economic burden of a disease. However, variable cost inventories make it difficult to interpret and compare costs across multiple studies. Methods A scoping review was conducted to identify the component costs and the respective data sources used for estimating the cost of foodborne illnesses in a population. This review was accomplished by: (1) identifying the research question and relevant literature, (2) selecting the literature, (3) charting, collating, and summarizing the results. All pertinent data were extracted at the level of detail reported in a study, and the component cost and source data were subsequently grouped into themes. Results Eighty-four studies were identified that described the cost of foodborne illness in humans. Most studies (80%) were published in the last two decades (1992–2012) in North America and Europe. The 10 most frequently estimated costs were due to illnesses caused by bacterial foodborne pathogens, with non-typhoidal Salmonella spp. being the most commonly studied. Forty studies described both individual (direct and indirect) and societal level costs. The direct individual level component costs most often included were hospital services, physician personnel, and drug costs. The most commonly reported indirect individual level component cost was productivity losses due to sick leave from work. Prior estimates published in the literature were the most commonly used source of component cost data. Data sources were not provided or specifically linked to component costs in several studies. Conclusions The results illustrated a highly variable depth and breadth of individual and societal level component costs, and a wide range of data sources being used. This scoping review can be used as evidence that there is a lack of standardization in cost inventories in

  15. DIRECTIONAL COUPLERS

    DOEpatents

    Nigg, D.J.

    1961-12-01

    A directional coupler of small size is designed. Stripline conductors of non-rectilinear configuration, and separated from each other by a thin dielectric spacer. cross each other at least at two locations at right angles, thus providing practically pure capacitive coupling which substantially eliminates undesirable inductive coupling. The conductors are sandwiched between a pair of ground planes. The coupling factor is dependent only on the thickness and dielectric constant of the dielectric spacer at the point of conductor crossover. (AEC)

  16. DIRECTIONAL ANTENNA

    DOEpatents

    Bittner, B.J.

    1958-05-20

    A high-frequency directional antenna of the 360 d scaring type is described. The antenna has for its desirable features the reduction in both size and complexity of the mechanism for rotating the antenna through its scanning movement. These advantages result from the rotation of only the driven element, the reflector remaining stationary. The particular antenna structure comprises a refiector formed by a plurality of metallic slats arranged in the configuration of an annular cage having the shape of a zone of revolution. The slats are parallel to each other and are disposed at an angle of 45 d to the axis of the cage. A directional radiator is disposed inside the cage at an angle of 45 d to the axis of the cage in the same direction as the reflecting slats which it faces. As the radiator is rotated, the electromagnetic wave is reflected from the slats facing the radiator and thereafter passes through the cage on the opposite side, since these slats are not parallel with the E vector of the wave.

  17. Evaluation of ranges of motion of a new constrained acetabular prosthesis for canine total hip replacement

    PubMed Central

    2013-01-01

    Background Total hip replacement (THR) is considered to be the most effective treatment option for advanced osteoarthritis of the hip in large breed dogs. However, a proportion of post-THR patients suffer prosthesis dislocation for various reasons, which may be addressed by a constrained acetabular prosthesis design. The study proposed a new THR with constrained acetabular component that aimed to decrease the incidence of postoperative dislocation while maintaining the necessary range of motion (ROM); and, through computer-simulated implantations, evaluated the ROM of the THR with and without malpositioning of the acetabular component. Methods A new THR with a constrained acetabular component that had an inward eccentric lining and a 60° cut-out on the dorsal side was designed, and its computer-aided design models were implanted into the pelvic and femoral models reconstructed from the computed tomography data of six healthy Labrador Retriever dogs. The allowable and functional ROM of the implanted THR were determined via computer simulations. The contact patterns between the bone or the prosthetic components at extreme positions of the THR were analyzed. Influence of malpositioning of the acetabular component on the ROM was assessed. Results The means (SD) of the functional ranges for flexion, extension, adduction, abduction, internal rotation and external rotation were 51.8° (6.6°), 163.3° (7.3°), 33.5° (5.7°), 74.0° (3.7°), 41.5° (8.3°) and 65.2° (9.9°), respectively. Malpositioning of the acetabular component by 20° in one direction was found to reduce ROM in other directions (reducing lateral opening: flexion: 12°, adduction: 20°, internal/external rotations: < 20°; increasing lateral opening: extension and abduction: < 16°; reducing retroversion: extension: < 20°, abduction: 15°, external rotation: < 20°; increasing retroversion: flexion: < 20°, abduction, adduction and internal rotation: 20°). Conclusions From the computer

  18. Component-specific modeling

    NASA Technical Reports Server (NTRS)

    Mcknight, R. L.

    1985-01-01

    A series of interdisciplinary modeling and analysis techniques that were specialized to address three specific hot section components are presented. These techniques will incorporate data as well as theoretical methods from many diverse areas including cycle and performance analysis, heat transfer analysis, linear and nonlinear stress analysis, and mission analysis. Building on the proven techniques already available in these fields, the new methods developed will be integrated into computer codes to provide an accurate, and unified approach to analyzing combustor burner liners, hollow air cooled turbine blades, and air cooled turbine vanes. For these components, the methods developed will predict temperature, deformation, stress and strain histories throughout a complete flight mission.

  19. Components in the Pipeline

    SciTech Connect

    Gorton, Ian; Wynne, Adam S.; Liu, Yan; Yin, Jian

    2011-02-24

    Scientists commonly describe their data processing systems metaphorically as software pipelines. These pipelines input one or more data sources and apply a sequence of processing steps to transform the data and create useful results. While conceptually simple, pipelines often adopt complex topologies and must meet stringent quality of service requirements that place stress on the software infrastructure used to construct the pipeline. In this paper we describe the MeDICi Integration Framework, which is a component-based framework for constructing complex software pipelines. The framework supports composing pipelines from distributed heterogeneous software components and provides mechanisms for controlling qualities of service to meet demanding performance, reliability and communication requirements.

  20. Blood Component Therapy

    PubMed Central

    Kelton, J. G.

    1984-01-01

    Human blood has been transfused for about 60-70 years. Over this time, the practice of blood transfusion has changed dramatically. One major change is the separation of blood into its various components. As a result, the patient can receive only the blood component in which he is deficient. In this way, the risk of side effects—particularly hepatitis—is lessened. This article briefly reviews the various blood products, the indications for their use, and some associated risks. These products include oxygen-carrying products, plasma products, blood products used to correct hemostatic defects, and immune globulin. PMID:21279096

  1. Ceramic component for electrodes

    DOEpatents

    Marchant, David D.; Bates, J. Lambert

    1980-01-01

    A ceramic component suitable for preparing MHD generator electrodes having the compositional formula: Y.sub.x (Mg.sub.y Cr.sub.z).sub.w Al.sub.(1-w) O.sub.3 where x=0.9 to 1.05, y=0.02 to 0.2, z=0.8 to 1.05 and w=1.0 to 0.5. The component is resistant to the formation of hydration products in an MHD environment, has good electrical conductivity and exhibits a lower electrochemical corrosion rate than do comparable compositions of lanthanum chromite.

  2. An apparatus for remotely handling components

    SciTech Connect

    Szkrybalo, G.A.; Griffin, D.L.

    1992-12-31

    The inventive apparatus for remotely handling barlike components which define a longitudinal direction includes a gripper mechanism for gripping the component including first and second gripper members longitudinally fixedly spaced from each other and oriented parallel to each other in planes transverse to the longitudinal direction. Each gripper member includes a jaw having at least one V-groove with opposing surfaces intersecting at a base and extending radially relative to the longitudinal direction for receiving the component in an open end between the opposing surfaces. The V-grooves on the jaw plate of t he first and second gripper members are aligned in the longitudinal direction to support the component in the first and second gripper members. A jaw is rotatably mounted on and a part of each of the first and second gripper members for selectively assuming a retracted mode in which the open end of the V-groove is unobstructed and active mode in which the jaw spans the open end of the V-groove in the first and second gripper members. The jaw has a locking surface for contacting the component in the active mode to secure the component between the locking surface of the jaw and the opposing surfaces of the V-groove. The locking surface has a plurality of stepped portions, each defining a progressively decreasing radial distance between the base of the V-groove and the stepped portion opposing the base to accommodate varying sizes of components. In a preferred embodiment, the apparatus also includes a control mechanism for remotely controlling movement of the jaw in the locking mode to assume one of a plurality of locking positions corresponding to positioning one of the stepped portions opposite the base.

  3. Space-Based Range Safety and Future Space Range Applications

    NASA Technical Reports Server (NTRS)

    Whiteman, Donald E.; Valencia, Lisa M.; Simpson, James C.

    2005-01-01

    The National Aeronautics and Space Administration (NASA) Space-Based Telemetry and Range Safety (STARS) study is a multiphase project to demonstrate the performance, flexibility and cost savings that can be realized by using space-based assets for the Range Safety [global positioning system (GPS) metric tracking data, flight termination command and range safety data relay] and Range User (telemetry) functions during vehicle launches and landings. Phase 1 included flight testing S-band Range Safety and Range User hardware in 2003 onboard a high-dynamic aircraft platform at Dryden Flight Research Center (Edwards, California, USA) using the NASA Tracking and Data Relay Satellite System (TDRSS) as the communications link. The current effort, Phase 2, includes hardware and packaging upgrades to the S-band Range Safety system and development of a high data rate Ku-band Range User system. The enhanced Phase 2 Range Safety Unit (RSU) provided real-time video for three days during the historic Global Flyer (Scaled Composites, Mojave, California, USA) flight in March, 2005. Additional Phase 2 testing will include a sounding rocket test of the Range Safety system and aircraft flight testing of both systems. Future testing will include a flight test on a launch vehicle platform. This paper discusses both Range Safety and Range User developments and testing with emphasis on the Range Safety system. The operational concept of a future space-based range is also discussed.

  4. Space-Based Range Safety and Future Space Range Applications

    NASA Technical Reports Server (NTRS)

    Whiteman, Donald E.; Valencia, Lisa M.; Simpson, James C.

    2005-01-01

    The National Aeronautics and Space Administration Space-Based Telemetry and Range Safety study is a multiphase project to demonstrate the performance, flexibility and cost savings that can be realized by using space-based assets for the Range Safety (global positioning system metric tracking data, flight termination command and range safety data relay) and Range User (telemetry) functions during vehicle launches and landings. Phase 1 included flight testing S-band Range Safety and Range User hardware in 2003 onboard a high-dynamic aircraft platform at Dryden Flight Research Center (Edwards, California) using the NASA Tracking and Data Relay Satellite System as the communications link. The current effort, Phase 2, includes hardware and packaging upgrades to the S-band Range Safety system and development of a high data rate Ku-band Range User system. The enhanced Phase 2 Range Safety Unit provided real-time video for three days during the historic GlobalFlyer (Scaled Composites, Mojave, California) flight in March, 2005. Additional Phase 2 testing will include a sounding rocket test of the Range Safety system and aircraft flight testing of both systems. Future testing will include a flight test on a launch vehicle platform. This report discusses both Range Safety and Range User developments and testing with emphasis on the Range Safety system. The operational concept of a future space-based range is also discussed.

  5. Attitude Control Propulsion Components, Volume 1

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Effort was made to include as much engineering information on each component as possible, consistent with usefulness and catalog size limitations. The contents of this catalog contain components which were qualified for use with spacecraft monopropellant hydrazine and inert gas attitude control systems. Thrust ranges up to 44.5 N (10.0 lbf) for hydrazine and inert gas sytems were considered. Additionally, some components qualified for uses other than spacecraft attitude control are included because they are suitable for use in attitude controls systems.

  6. Self-Directed Learning: Exploring the Fears.

    ERIC Educational Resources Information Center

    Ricard, Virginia B.

    Many degree programs for adults include a self-directed learning component to offer learners the opportunity to use mature skills in a flexible learning environment. Problems with making the self-directed component work may be the learning setting, learner attitudes, and fears of both skilled and less skilled adult learners. Some learner fears are…

  7. Informed Test Component Weighting.

    ERIC Educational Resources Information Center

    Rudner, Lawrence M.

    2001-01-01

    Identifies and evaluates alternative methods for weighting tests. Presents formulas for composite reliability and validity as a function of component weights and suggests a rational process that identifies and considers trade-offs in determining weights. Discusses drawbacks to implicit weighting and explicit weighting and the difficulty of…

  8. Revisiting Wilson's Moral Components.

    ERIC Educational Resources Information Center

    Straughan, Roger

    2000-01-01

    Discusses the reasons why educational researchers and teachers never embraced the ideas of John Wilson as they related to his components of morality in moral education. States that through this examination, the strengths and weaknesses of Wilson's approach can be appraised. (CMK)

  9. Molecular Models Candy Components

    ERIC Educational Resources Information Center

    Coleman, William F.

    2007-01-01

    An explanation of various principles of chemistry in a paper by Fanny Ennever by the use of candy is described. The paper explains components of sucrose and the invert sugar that results from the hydrolysis of sucrose and will help students in determining whether the products are indeed hydrates of carbon.

  10. Liquid rocket valve components

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A monograph on valves for use with liquid rocket propellant engines is presented. The configurations of the various types of valves are described and illustrated. Design criteria and recommended practices for the various valves are explained. Tables of data are included to show the chief features of valve components in use on operational vehicles.

  11. Modelling directional solidification

    NASA Technical Reports Server (NTRS)

    Wilcox, William R.; Regel, Liya L.

    1994-01-01

    This grant, NAG8-831, was a continuation of a previous grant, NAG8-541. The long range goal of this program has been to develop an improved understanding of phenomena of importance to directional solidification, in order to enable explanation and prediction of differences in behavior between solidification on Earth and in space. Emphasis in the recently completed grant was on determining the influence of perturbations on directional solidification of InSb and InSb-GaSb alloys. In particular, the objective was to determine the influence of spin-up/spin-down (ACRT), electric current pulses and vibrations on compositional homogeneity and grain size.

  12. [Research into simultaneous spectrophotometric determination of components in cough syrup by principal component regression method].

    PubMed

    Zhang, Li-qing; Wu, Xiao-hua; Tang, Xi; Zhu, Xian-liang; Su, Wen-ting

    2002-06-01

    Principal component regression (PCR) method is used to analyse five components: acetaminophen, p-aminophenol, caffeine, chlorphenamine maleate and guaifenesin. The basic principle and the analytical step of the approach are described in detail. The computer program of LHG is based on VB language. The experimental result shows that the PCR method has no systematical error as compared to classical method. The experimental result shows that the average recovery of each component is all in the range from 96.43% to 107.14%. Each component obtains satisfactory result without any pre-separation. The approach is simple, rapid and suitable for the computer-aid analysis. PMID:12938324

  13. Developing a Model Component

    NASA Technical Reports Server (NTRS)

    Fields, Christina M.

    2013-01-01

    The Spaceport Command and Control System (SCCS) Simulation Computer Software Configuration Item (CSCI) is responsible for providing simulations to support test and verification of SCCS hardware and software. The Universal Coolant Transporter System (UCTS) was a Space Shuttle Orbiter support piece of the Ground Servicing Equipment (GSE). The initial purpose of the UCTS was to provide two support services to the Space Shuttle Orbiter immediately after landing at the Shuttle Landing Facility. The UCTS is designed with the capability of servicing future space vehicles; including all Space Station Requirements necessary for the MPLM Modules. The Simulation uses GSE Models to stand in for the actual systems to support testing of SCCS systems during their development. As an intern at Kennedy Space Center (KSC), my assignment was to develop a model component for the UCTS. I was given a fluid component (dryer) to model in Simulink. I completed training for UNIX and Simulink. The dryer is a Catch All replaceable core type filter-dryer. The filter-dryer provides maximum protection for the thermostatic expansion valve and solenoid valve from dirt that may be in the system. The filter-dryer also protects the valves from freezing up. I researched fluid dynamics to understand the function of my component. The filter-dryer was modeled by determining affects it has on the pressure and velocity of the system. I used Bernoulli's Equation to calculate the pressure and velocity differential through the dryer. I created my filter-dryer model in Simulink and wrote the test script to test the component. I completed component testing and captured test data. The finalized model was sent for peer review for any improvements. I participated in Simulation meetings and was involved in the subsystem design process and team collaborations. I gained valuable work experience and insight into a career path as an engineer.

  14. Developing a Model Component

    NASA Technical Reports Server (NTRS)

    Fields, Christina M.

    2013-01-01

    The Spaceport Command and Control System (SCCS) Simulation Computer Software Configuration Item (CSCI) is,. responsible for providing simulations to support test and verification of SCCS hardware and software. The Universal Coolant Transporter System (UCTS) is a Space Shuttle Orbiter support piece of the Ground Servicing Equipment (GSE). The purpose of the UCTS is to provide two support services to the Space Shuttle Orbiter immediately after landing at the Shuttle Landing Facility. The Simulation uses GSE Models to stand in for the actual systems to support testing of SCCS systems s:luring their development. As an intern at KSC, my assignment was to develop a model component for the UCTS. I was given a fluid component (drier) to model in Matlab. The drier was a Catch All replaceable core type filter-drier. The filter-drier provides maximum protection for the thermostatic expansion valve and solenoid valve from dirt that may be in the system. The filter-drier also protects the valves from freezing up. I researched fluid dynamics to understand the function of my component. I completed training for UNIX and Simulink to help aid in my assignment. The filter-drier was modeled by determining affects it has on the pressure, velocity and temperature of the system. I used Bernoulli's Equation to calculate the pressure and velocity differential through the dryer. I created my model filter-drier in Simulink and wrote the test script to test the component. I completed component testing and captured test data. The finalized model was sent for peer review for any improvements.

  15. Wide Range SET Pulse Measurement

    NASA Technical Reports Server (NTRS)

    Shuler, Robert L.; Chen, Li

    2012-01-01

    A method for measuring a wide range of SET pulses is demonstrated. Use of dynamic logic, faster than ordinary CMOS, allows capture of short pulses. A weighted binning of SET lengths allows measurement of a wide range of pulse lengths with compact circuitry. A pulse-length-conservative pulse combiner tree routes SETs from combinational logic to the measurement circuit, allowing SET measurements in circuits that cannot easily be arranged in long chains. The method is applied to add-multiplex combinational logic, and to an array of NFET routing switches, at .35 micron. Pulses are captured in a chain of Domino Logic AND gates. Propagation through the chain is frozen on the trailing edge by dropping low the second "enable" input to the AND gates. Capacitive loading is increased in the latter stages to create an approximately logarithmic weighted binning, so that a broad range of pulse lengths can be captured with a 10 stage capture chain. Simulations show pulses can be captured which are 1/5th the length of those typically captured with leading edge triggered latch methods, and less than the length of those captured with a trailing edge latch method. After capture, the pulse pattern is transferred to an SEU protected shift register for readout. 64 instances of each of two types of logic are used as targets. One is a full adder with a 4 to 1 mux on its inputs. The other is a 4 x 4 NFET routing matrix. The outputs are passed through buffered XNOR comparators to identify pulses, which are merged in a buffered not-nand (OR) tree designed to avoid pulse absorption as much as possible. The output from each of the two test circuits are input into separate pulse measurement circuits. Test inputs were provided so that the circuit could be bench tested and calibrated. A third SET measurement circuit with no inputs was used to judge the contribution from direct hits on the measurement circuit. Heavy ions were used with an LET range from 12 to 176. At LET of 21 and below, the very

  16. Lightning threat warning system at the Tonopah Test Range

    SciTech Connect

    Smith, R

    1992-07-01

    This report documents the lightning threat warning system at the Tonopah Test Range and the technology it uses. The report outlines each of the system's individual components and the information each contributes.

  17. Evaluation of silicon neutron resonance parameters in the thermal to 1800 keV energy range.

    PubMed

    Derrien, H; Leal, L C; Guber, K H; Larson, N M

    2005-01-01

    Because silicon is a major constituent of concrete and soil, neutron and gamma ray information on silicon is important for reactor shielding and criticality safety calculations. Therefore, much effort was put into the ENDF/B-VI evaluation for the three stable isotopes of silicon. The neutron capture cross section of natural silicon was recently measured at the Oak Ridge Electron Linear Accelerator (ORELA) in the energy range 1-700 keV. Using the ENDF/B-VI evaluation for initial values, a new evaluation of the resonance parameters was performed by adding the results of the ORELA capture measurements to the experimental database. The computer code SAMMY was used for the analysis of the experimental data; the new version of SAMMY allows accurate calculations of the self-shielding and multiple scattering effects in the capture measurements. The accuracy of the radiative capture widths of the resonances was improved by this analysis. Accurate values of the s-, p- and d-wave neutron strength functions were also obtained. Although the resonance capture component of the present evaluation is 2-3 times smaller than that in ENDF/B-VI, the total capture cross section is much larger, at least for energies >250 keV, because the direct capture component contributes values of the same order of magnitude as the resonance component. The direct component was not taken into account in the ENDF/B-VI evaluation and was calculated for the first time in the present evaluation. PMID:16381717

  18. Visible-Light Photoredox Catalyzed Three-Component Cyclization of 2H-Azirines, Alkynyl Bromides, and Molecular Oxygen to Oxazole Skeleton.

    PubMed

    Chen, Lili; Li, Hongji; Li, Pinhua; Wang, Lei

    2016-08-01

    A novel three-component cyclization of 2H-azirines, alkynyl bromides, and molecular oxygen under visible-light photoredox catalysis at room temperature has been developed, which provides a direct approach to a wide range of substituted oxazoles in moderate to good yields. PMID:27456612

  19. Electric vehicle drive train components

    SciTech Connect

    Silver, F.

    1994-12-31

    Power Control Systems has developed a family of electric vehicle drive systems that range from 65 horsepower through 300 horse power. These propulsion systems support vehicle applications ranging from light cars and pickups to buses and trucks weighing as much as 40,000 lbs (18,400 kg). These robust systems are designed specifically for automotive applications including safety, electromagnetic emissions, and environment ruggedness. Dolphin Drive Systems are very flexible. Their inverter controllers are programmable and can be provided as stand alone components matched to customer specified motors. A selection of pre-calibrated systems including motor and inverter/controller can be provided. Accessory tools are also available for customer self programming. Dolphin Drive Systems provide precision control of AC induction motors providing excellent torque-speed performance usually eliminating the need for multistage transmissions. In addition, they are very efficient over a wide speed/torque range. This provides for excellent power management over a variety of continuous speed and stop and go applications.

  20. Intentionally Short-Range Communications (ISRC)

    NASA Astrophysics Data System (ADS)

    Yen, J.; Poirier, P.; Obrien, M.

    1994-02-01

    The U.S. Marine Corps (USMC) desired to develop short-range communications links whose ranges are intentionally limited to very short distances. These links support tactical missions such as LAN Backbone, Wideband Data Link, and Company Radio. The short-range limitation arises from the need for low probability of detection and intercept (LPD/LPI). Since the detection of an undecipherable transmission would still provide an enemy with information regarding transmitter location and allow him to take countermeasures, the Marine Corps Systems Command (MARCORSYSCOM) is sponsoring the development of technologies that can be LPD by their very nature. The Intentionally Short-Range Communications (ISRC) project at the Naval Command, Control and Ocean Surveillance Center (NCCOSC) RDT&E Division (NRaD) is pursuing feasibility studies for these USMC missions based on such technologies as ultraviolet (LTV) lamps, UV lasers, infrared (IR) lasers, millimeter waves and direct sequence spread spectrum (DSSS) at radio frequencies.

  1. Recent firing range suicides in South Australia.

    PubMed

    Austin, Amy E; van den Heuvel, Corinna; Heath, Karen; Gilbert, John D; Byard, Roger W

    2012-11-01

    Two cases are reported from South Australia, where deaths occurred that were due to single self-inflicted gunshot wounds to the head in individuals who were visiting indoor firearm ranges. Case 1: A 54-year-old man visiting an indoor firing range placed a .357 magnum handgun to his head and fired one shot. Case 2: A 23-year-old woman who was being instructed in firearm usage at an indoor firing range placed a 9 mm handgun to her head and fired one shot. In both cases, deaths were due to cerebral laceration with skull fracture. Firing ranges may be utilized by individuals who are seeking weapons for suicide attempts, and suicide may be successfully undertaken at such locations even while a victim is under direct supervision. In jurisdictions, where firearm ownership is strictly legislated, it may be that clubs can inadvertently provide access to firearms for this type of activity. PMID:22471964

  2. Sandia_HighTemperatureComponentEvaluation_2015.

    SciTech Connect

    Cashion, Avery T.

    2015-03-01

    The objective of this project is to perform independent evaluation of high temperature components to determine their suitability for use in high temperature geothermal tools. Development of high temperature components has been increasing rapidly due to demand from the high temperature oil and gas exploration and aerospace industries. Many of these new components are at the late prototype or first production stage of development and could benefit from third party evaluation of functionality and lifetime at elevated temperatures. In addition to independent testing of new components, this project recognizes that there is a paucity of commercial-off-the-shelf COTS components rated for geothermal temperatures. As such, high-temperature circuit designers often must dedicate considerable time and resources to determine if a component exists that they may be able to knead performance out of to meet their requirements. This project aids tool developers by characterization of select COTS component performances beyond published temperature specifications. The process for selecting components includes public announcements of project intent (e.g., FedBizOps), direct discussions with candidate manufacturers,and coordination with other DOE funded programs.

  3. International Laser Ranging Service (ILRS) 1999 Annual Report

    NASA Technical Reports Server (NTRS)

    Pearlman, Michael (Editor); Taggert, Linda (Editor)

    2000-01-01

    This 1999 Annual Report of the International Laser Ranging Service (ILRS) is comprised of individual contributions from ILRS components within the international geodetic community. This report documents the work of the ILRS components from the inception of the Service through December 31,1999. Since the service has only recently been established, the ILRS associates decided to publish this Annual report as a reference to our organization and its components.

  4. Spanwise measurements of vertical components of atmospheric turbulence

    NASA Technical Reports Server (NTRS)

    Sleeper, Robert K.

    1990-01-01

    Correlation and spectrum magnitude estimates are computed for vertical gust velocity measurements at the nose and wing tips of a NASA B-57B aircraft for six level flight, low speed and low altitude runs and are compared with those of the von Karman atmospheric turbulence model extended for spanwise relationships. The distance between the wing tips was 62.6 ft. Airspeeds ranged from about 330 to 400 ft/sec, heights above the ground ranged from near ground level to about 5250 ft. and gust velocity standard deviations ranged from 4.10 to 8.86 ft/sec. Integral scale lengths, determined by matching measured autocorrelation estimates with those of the model, ranged from 410 to 2050 ft. Digital signals derived from piezoelectric sensors provided continuous pressure and airspeed measurements. Some directional acceleration sensitivity of the sensors was eliminated by sensor orientation, and their performance was spectrally verified for the higher frequencies with supplemental onboard piezoresistive sensors. The model appeared to satisfactorily predict the trends of the measured cross-correlations and cross-spectrum magnitudes, particularly between the nose and wing tips. However, the measured magnitude estimates of the cross-spectra between the wing tips exceeded the predicted levels at the higher frequencies. Causes for the additional power across the wing tips were investigated. Vertical gust velocity components evaluated along and lateral to the flight path implied that the frozen-turbulence-field assumption is a suitable approximation.

  5. Multibody dynamics: Modeling component flexibility with fixed, free, loaded, constraint, and residual modes

    NASA Technical Reports Server (NTRS)

    Spanos, John T.; Tsuha, Walter S.

    1989-01-01

    The assumed-modes method in multibody dynamics allows the elastic deformation of each component in the system to be approximated by a sum of products of spatial and temporal functions commonly known as modes and modal coordinates respectively. The choice of component modes used to model articulating and non-articulating flexible multibody systems is examined. Attention is directed toward three classical Component Mode Synthesis (CMS) methods whereby component normal modes are generated by treating the component interface (I/F) as either fixed, free, or loaded with mass and stiffness contributions from the remaining components. The fixed and free I/F normal modes are augmented by static shape functions termed constraint and residual modes respectively. A mode selection procedure is outlined whereby component modes are selected from the Craig-Bampton (fixed I/F plus constraint), MacNeal-Rubin (free I/F plus residual), or Benfield-Hruda (loaded I/F) mode sets in accordance with a modal ordering scheme derived from balance realization theory. The success of the approach is judged by comparing the actuator-to-sensor frequency response of the reduced order system with that of the full order system over the frequency range of interest. A finite element model of the Galileo spacecraft serves as an example in demonstrating the effectiveness of the proposed mode selection method.

  6. Pulse spreading and range correction analysis for satellite laser ranging

    NASA Technical Reports Server (NTRS)

    Schwartz, Jon A.

    1990-01-01

    The pulse spreading resulting from light detection and ranging measurements of the range to earth-orbiting satellites is described. An analysis quantifying this pulse spreading and the calculation of corrections to be applied to the lidar range determination of satellites is detailed.

  7. Pulse spreading and range correction analysis for satellite laser ranging.

    PubMed

    Schwartz, J A

    1990-09-01

    The pulse spreading resulting from light detection and ranging measurements of the range to earth-orbiting satellites is described. An analysis quantifying this pulse spreading and the calculation of corrections to be applied to the lidar range determination of satellites is detailed. PMID:20567459

  8. Direct ELISA.

    PubMed

    Lin, Alice V

    2015-01-01

    First described by Engvall and Perlmann, the enzyme-linked immunosorbent assay (ELISA) is a rapid and sensitive method for detection and quantitation of an antigen using an enzyme-labeled antibody. Besides routine laboratory usage, ELISA has been utilized in medical field and food industry as diagnostic and quality control tools. Traditionally performed in 96-well or 384-well polystyrene plates, the technology has expanded to other platforms with increase in automation. Depending on the antigen epitope and availability of specific antibody, there are variations in ELISA setup. The four basic formats are direct, indirect, sandwich, and competitive ELISAs. Direct ELISA is the simplest format requiring an antigen and an enzyme-conjugated antibody specific to the antigen. This chapter describes the individual steps for detection of a plate-bound antigen using a horseradish peroxidase (HRP)-conjugated antibody and luminol-based enhanced chemiluminescence (ECL) substrate. The methodological approach to optimize the assay by chessboard titration is also provided. PMID:26160564

  9. PHASE CHEMISTRY OF TANK SLUDGE RESIDUAL COMPONENTS

    EPA Science Inventory

    It will not be possible to recover all the contaminated sludge from the bottoms of decommissioned waste storage tanks. This research is directed at providing a credible model for the release of radionuclides from residual sludge. Sludge components that are the prime actors in ret...

  10. Short Range Correlations, Inclusive Electron-Nucleus Scattering, and Scaling

    SciTech Connect

    Day, Donal

    2008-10-13

    The presence of high momentum components in the nuclear wavefunction has been of great interest for many years. Unfortunately high momentum components, associated with the short range correlations (SRC), have been difficult to isolate unambiquously. Inclusive electron scattering cross sections in the quasielastic region have been measured over a wide range of energy and momentum transfers from very light to very heavy nuclei and the scaling analyses of these data can provide useful information on the presence of SRCs and more.

  11. Direct search for dark matter

    SciTech Connect

    Yoo, Jonghee; /Fermilab

    2009-12-01

    Dark matter is hypothetical matter which does not interact with electromagnetic radiation. The existence of dark matter is only inferred from gravitational effects of astrophysical observations to explain the missing mass component of the Universe. Weakly Interacting Massive Particles are currently the most popular candidate to explain the missing mass component. I review the current status of experimental searches of dark matter through direct detection using terrestrial detectors.

  12. Electroslag component casting. [Nickel aluminide

    SciTech Connect

    Sikka, V.K.

    1986-01-01

    This project is directed toward the development of electroslag-casting (ESC) technology for use in coal conversion components such as valve bodies, pump housings, and pipe fittings. The aim is also to develop a sufficient data base to permit electroslag casting to become an ASME Code-accepted process. It is also intended to transfer the ESC process technology to private industry. A total of 32 electroslag castings of 2.25Cr-1Mo, 9Cr-1Mo, type 316, and nickel aluminide were procured from four facilities for evaluation (Table 1). The most complex castings procured during this program were the valve bodies shown in Figure 2. The castings were subjected to various heat treatments (Table 2), checked for chemical composition uniformity from top to bottom, and subjected to macrostructural evaluation and mechanical properties testing. Results are discussed. 10 refs., 7 figs., 3 tabs.

  13. Fast Steerable Principal Component Analysis

    PubMed Central

    Zhao, Zhizhen; Shkolnisky, Yoel; Singer, Amit

    2016-01-01

    Cryo-electron microscopy nowadays often requires the analysis of hundreds of thousands of 2-D images as large as a few hundred pixels in each direction. Here, we introduce an algorithm that efficiently and accurately performs principal component analysis (PCA) for a large set of 2-D images, and, for each image, the set of its uniform rotations in the plane and their reflections. For a dataset consisting of n images of size L × L pixels, the computational complexity of our algorithm is O(nL3 + L4), while existing algorithms take O(nL4). The new algorithm computes the expansion coefficients of the images in a Fourier–Bessel basis efficiently using the nonuniform fast Fourier transform. We compare the accuracy and efficiency of the new algorithm with traditional PCA and existing algorithms for steerable PCA. PMID:27570801

  14. Liquid-Liquid phase transition in a single component system

    NASA Astrophysics Data System (ADS)

    Franzese, Giancarlo; Skibinsky, Anna; Buldyrev, Sergey; Stanley, H. Eugene

    2001-06-01

    Recent experimental results indicate that phosphorus, a single-component system, can have a high-density liquid (HDL) and a low-density liquid (LDL) phase. A first-order LDL-HDL transition line ending in a critical point is consistent with experimental data and Molecular Dynamics (MD) simulations for a variety of single-component systems such as water, silica and carbon, but a coherent and general interpretation of the LDL-HDL transition is lacking. By means of MD, we show that the LDL-HDL transition can be directly related to an interaction potential with an attractive part and with not one but `two' preferred short-range repulsive distances. This kind of interaction is common to other single-component materials in the liquid state, in particular liquid metals. For the fisrt time, we show that the LDL-HDL transition can occur in systems with no density anomaly, opening an experimental challenge to uncover a liquid-liquid transition in systems like liquid metals, regardless of the presence of the density anomaly.

  15. Industrial applications of shearography for inspection of aircraft components

    NASA Astrophysics Data System (ADS)

    Krupka, Rene; Walz, Thomas; Ettemeyer, Andreas

    2005-04-01

    Shearography has been validated as fast and reliable inspection technique for aerospace components. Following several years phase of evaluation of the technique, meanwhile, shearography has entered the industrial production inspection. The applications basically range from serial inspection in the production line to field inspection in assembly and to applications in the maintenance and repair area. In all applications, the main advantages of shearography, as very fast and full field insection and high sensitivity even on very complex on composite materials have led to the decision for laser shearography as inspection tool. In this paper, we present some highlights of industrial shearography inspection. One of the first industrial installations of laser shearography in Europe was a fully automatic inspection system for helicopter rotorblades. Complete rotor blades are inspected within 10 minutes on delaminations and debondingg in the composite structure. In case of more complex components, robotic manipulation of the shearography camera has proven to be the optimal solution. An industry 6-axis robot give utmost flexibility to position the camera in any angle and distance. Automatic defect marking systems have also been introduced to indicate the exact position of the defect directly on the inspected component. Other applications are shearography inspection systems for abradable seals in jet engines and portable shearography inspection systems for maintenance and repair inspection in the field. In this paper, recent installations of automatice inspection systems in aerospace industries are presented.

  16. Industrial applications of shearography for inspections of aircraft components

    NASA Astrophysics Data System (ADS)

    Krupka, Rene; Waltz, T.; Ettemeyer, Andreas

    2003-05-01

    Shearography has been validated as fast and reliable inspection technique for aerospace components. Following several years phase of evaluation of the technique, meanwhile, shearography has entered the industrial production inspection. The applications basically range from serial inspection in the production line to field inspection in assembly and to applications in the maintenance and repair area. In all applications, the main advantages of shearography, as very fast and full field inspection and high sensitivity even on very complex composite materials have led to the decision for laser shearography as inspection tool. In this paper, we present examples of recent industrial shearography inspection systems in the field of aerospace. One of the first industrial installations of laser shearography in Europe was a fully automatic inspection system for helicopter rotorblades. Complete rotor blades are inspected within 10 minutes on delaminations and debondings in the composite structure. In case of more complex components, robotic manipulation of the shearography camera has proven to be the optimum solution. An industry 6-axis robot gives utmost flexibility to position the camera in any angle and distance. Automatic defect marking systems have also been introduced to indicate the exact position of the defect directly on the inspected component. Other applications cover the inspection of abradable seals in jet engines and portable shearography inspection systems for maintenance and repair inspection in the field.

  17. Magnetic circular dichroism in the hard X-ray range

    NASA Astrophysics Data System (ADS)

    Rogalev, A.; Wilhelm, F.

    2015-12-01

    An overview of X-ray magnetic circular dichroism (XMCD) spectroscopy in the hard X-ray range is presented. A short historical overview shows how this technique has evolved from the early days of X-ray physics to become a workhorse technique in the modern magnetism research As with all X-ray spectroscopies, XMCD has the advantage of being element specific. Interpretation of the spectra based on magneto-optical sum rules can provide unique information about spin and orbital moment carried by absorbing atom in both amplitude and direction, can infer magnetic interactions from element selective magnetization curves, can allow separation of magnetic and non-magnetic components in heterogeneous systems. The review details the technology currently available for XMCD measurements in the hard X-ray range referring to the ESRF beamline ID12 as an example. The strengths of hard X-ray magnetic circular dichroism technique are illustrated with a wide variety of representative examples, such as actinide based ferromagnets, paramagnetism in metals, pure metallic nanoparticles, exchange spring magnets, half metallic ferromagnets, magnetism at interfaces, and dilute magnetic semiconductors. In this way, we aim to encourage researchers from various scientific communities to consider XMCD as a tool to understanding the electronic and magnetic properties of their samples.

  18. Component-specific modeling

    NASA Technical Reports Server (NTRS)

    Mcknight, R. L.

    1984-01-01

    A series of interdisciplinary modeling and analysis techniques that were specialized to address three specific hot section components are presented. These techniques will incorporate data as well as theoretical methods from many diverse areas including cycle and performance analysis, heat transfer analysis, linear and nonlinear stress analysis, and mission analysis. Building on the proven techniques already available in these fields, the new methods developed will be integrated into computer codes to provide an accurate, efficient and unified approach to analyzing combustor burner liners, hollow air-cooled turbine blades and air-cooled turbine vanes. For these components, the methods developed will predict temperature, deformation, stress and strain histories throughout a complete flight mission.

  19. Bacterial Cell Wall Components

    NASA Astrophysics Data System (ADS)

    Ginsberg, Cynthia; Brown, Stephanie; Walker, Suzanne

    Bacterial cell-surface polysaccharides cells are surrounded by a variety of cell-surface structures that allow them to thrive in extreme environments. Components of the cell envelope and extracellular matrix are responsible for providing the cells with structural support, mediating intercellular communication, allowing the cells to move or to adhere to surfaces, protecting the cells from attack by antibiotics or the immune system, and facilitating the uptake of nutrients. Some of the most important cell wall components are polysaccharide structures. This review discusses the occurrence, structure, function, and biosynthesis of the most prevalent bacterial cell surface polysaccharides: peptidoglycan, lipopolysaccharide, arabinogalactan, and lipoarabinomannan, and capsular and extracellular polysaccharides. The roles of these polysaccharides in medicine, both as drug targets and as therapeutic agents, are also described.

  20. The noseleaf of Rhinolophus formosae focuses the Frequency Modulated (FM) component of the calls

    PubMed Central

    Vanderelst, Dieter; Lee, Ya-Fu; Geipel, Inga; Kalko, Elisabeth K. V.; Kuo, Yen-Min; Peremans, Herbert

    2013-01-01

    Bats of the family Rhinolophidae emit their echolocation calls through their nostrils and feature elaborate noseleaves shaping the directionality of the emissions. The calls of these bats consist of a long constant-frequency component preceded and/or followed by short frequency-modulated sweeps. While Rhinolophidae are known for their physiological specializations for processing the constant frequency part of the calls, previous evidence suggests that the noseleaves of these animals are tuned to the frequencies in the frequency modulated components of the calls. In this paper, we seek further support for this hypothesis by simulating the emission beam pattern of the bat Rhinolophus formosae. Filling the furrows of lancet and removing the basal lappets (i.e., two flaps on the noseleaf) we find that these conspicuous features of the noseleaf focus the emitted energy mostly for frequencies in the frequency-modulated components. Based on the assumption that this component of the call is used by the bats for ranging, we develop a qualitative model to assess the increase in performance due to the furrows and/or the lappets. The model confirms that both structures decrease the ambiguity in selecting relevant targets for ranging. The lappets and the furrows shape the emission beam for different spatial regions and frequency ranges. Therefore, we conclude that the presented evidence is in line with the hypothesis that different parts of the noseleaves of Rhinolophidae are tuned to different frequency ranges with at least some of the most conspicuous ones being tuned to the frequency modulated components of the calls—thus yielding strong evidence for the sensory importance of the component. PMID:23882226

  1. Diffusion bonding aeroengine components

    NASA Astrophysics Data System (ADS)

    Fitzpatrick, G. A.; Broughton, T.

    1988-10-01

    The use of diffusion bonding processes at Rolls-Royce for the manufacture of titanium-alloy aircraft engine components and structures is described. A liquid-phase diffusion bonding process called activated diffusion bonding has been developed for the manufacture of the hollow titanium wide chord fan blade. In addition, solid-state diffusion bonding is being used in the manufacture of hollow vane/blade airfoil constructions mainly in conjunction with superplastic forming and hot forming techniques.

  2. Component for thermoelectric generator

    DOEpatents

    Purdy, David L.

    1977-01-01

    In a thermoelectric generator, a component comprises a ceramic insulator, having over limited areas thereof, each area corresponding to a terminal end of thermoelectric wires, a coating of a first metal which adheres to the insulator, and an electrical thermoelectric junction including a second metal which wets said first metal and adheres to said terminal ends but does not wet said insulator, and a cloth composed of electrically insulating threads interlaced with thermoelectric wires.

  3. MEA Component Durability

    SciTech Connect

    Frisk, J. W.; Hicks, M.T.; Atanasoski, R. T.; Boand, W. M.; Schmoeckel, A. K.; Kurkowski, M. J.

    2004-11-01

    Membrane electrode assembly (MEA) lifetime of greater than 40,000 hours remains a goal of the fuel cell industry. However, there is a lack of fundamental understanding of the mechanisms of MEA degradation. Specifically, the relationship between component physical property changes and MEA performance decay has not been established. We report preliminary data relating changes in gas diffusion layer (GDL) physical properties to fuel cell performance decay.

  4. Solid state lighting component

    DOEpatents

    Yuan, Thomas; Keller, Bernd; Ibbetson, James; Tarsa, Eric; Negley, Gerald

    2010-10-26

    An LED component comprising an array of LED chips mounted on a planar surface of a submount with the LED chips capable of emitting light in response to an electrical signal. The LED chips comprise respective groups emitting at different colors of light, with each of the groups interconnected in a series circuit. A lens is included over the LED chips. Other embodiments can comprise thermal spreading structures included integral to the submount and arranged to dissipate heat from the LED chips.

  5. Solid state lighting component

    DOEpatents

    Keller, Bernd; Ibbetson, James; Tarsa, Eric; Negley, Gerald; Yuan, Thomas

    2012-07-10

    An LED component comprising an array of LED chips mounted on a planar surface of a submount with the LED chips capable of emitting light in response to an electrical signal. The LED chips comprise respective groups emitting at different colors of light, with each of the groups interconnected in a series circuit. A lens is included over the LED chips. Other embodiments can comprise thermal spreading structures included integral to the submount and arranged to dissipate heat from the LED chips.

  6. Injection molded component

    SciTech Connect

    James, Allister W; Arrell, Douglas J

    2014-09-30

    An intermediate component includes a first wall member, a leachable material layer, and a precursor wall member. The first wall member has an outer surface and first connecting structure. The leachable material layer is provided on the first wall member outer surface. The precursor wall member is formed adjacent to the leachable material layer from a metal powder mixed with a binder material, and includes second connecting structure.

  7. Atmospheric refraction errors in laser ranging systems

    NASA Technical Reports Server (NTRS)

    Gardner, C. S.; Rowlett, J. R.

    1976-01-01

    The effects of horizontal refractivity gradients on the accuracy of laser ranging systems were investigated by ray tracing through three dimensional refractivity profiles. The profiles were generated by performing a multiple regression on measurements from seven or eight radiosondes, using a refractivity model which provided for both linear and quadratic variations in the horizontal direction. The range correction due to horizontal gradients was found to be an approximately sinusoidal function of azimuth having a minimum near 0 deg azimuth and a maximum near 180 deg azimuth. The peak to peak variation was approximately 5 centimeters at 10 deg elevation and decreased to less than 1 millimeter at 80 deg elevation.

  8. Inertial Range Dynamics in Boussinesq Turbulence

    NASA Technical Reports Server (NTRS)

    Rubinstein, Robert

    1996-01-01

    L'vov and Falkovich have shown that the dimensionally possible inertial range scaling laws for Boussinesq turbulence, Kolmogorov and Bolgiano scaling, describe steady states with constant flux of kinetic energy and of entropy respectively. These scaling laws are treated as similarity solutions of the direct interaction approximation for Boussinesq turbulence. The Kolmogorov scaling solution corresponds to a weak perturbation by gravity of a state in which the temperature is a passive scalar but in which a source of temperature fluctuations exists. Using standard inertial range balances, the renormalized viscosity and conductivity, turbulent Prandtl number, and spectral scaling law constants are computed for Bolgiano scaling.

  9. Direct cervicoplasty.

    PubMed

    Jordan, J Randall

    2012-02-01

    The sagging neck, or "turkey gobbler" deformity, is one of the more common reasons that patients present to facial plastic surgeons. Although many of these patients might be best improved by a full rhytidectomy with periauricular incisions, skin flap undermining, and platysmal tightening, there are some patients who do not wish to undergo a full rhytidectomy. Some of these patients may be reasonably well served by a direct cervicoplasty or submentoplasty. The advantages of this approach include shorter operative time, faster recovery, and lower complication rates. The primary disadvantage is an anterior cervical incision that may be visible under some conditions. This article will review the options for skin incisions as well as technical details that may lead to a successful rejuvenation of the submental region. PMID:22418816

  10. Chondrites and Their Components

    NASA Astrophysics Data System (ADS)

    Scott, E. R. D.; Krot, A. N.

    Chondrites are extraordinary mixtures of materials with diverse origins that formed around other stars, in the solar nebula, and in their parent asteroids. Most chondrites were so severely altered by aqueous fluids, thermal metamorphism, and impacts that the original characteristics of their components have been largely erased. But a few pristine chondrites have preserved an exquisite mineralogical, chemical, isotopic, and chronological record of the first few million years of solar system history. The properties of diverse types of carbonaceous, ordinary, and enstatite chondrites focusing on the most pristine samples are reviewed to establish the chemical, isotopic, and mineralogical properties and origins of their components and to elucidate the asteroidal processes that modified them. Refractory inclusions - amoeboid olivine aggregates and Ca-Al-rich inclusions - were the first solids to form in the solar nebula near to the protosun. Chondrules and associated metallic Fe-Ni grains were still forming several million years later when the earliest planetesimals, which melted due to heat from 26Al decay, were colliding. In the least-altered chondrites, matrix material, which coats chondrules and other components, is largely composed of micrometer-sized silicates and amorphous materials, which formed at high temperatures, plus small amounts (up to 200 ppm) of presolar oxides and silicates.

  11. Artificial polarization components

    NASA Astrophysics Data System (ADS)

    Cescato, L.; Gluch, Ekkehard; Stork, Wilhelm; Streibl, Norbert

    1990-07-01

    High frequency surface relief structures are optically anisotropic and show interesting polarisation properties 1 . These properties can be used to produce polarizations components such as wave plates polarizers. polarizing beamsplitters etc. Our experimental results show that even gratings with relatively low spatial frequency ( periods A ) exhibit a strong phase retardation and can be used as quarter-wave plates. k INTRODUC11ON The artificial birefringence exhibited by ultrahigh frequency gratings of dielectric materials can be used to produce various polarization components2 . Such components have applications in integrated optics as well as in free space optics. In order to produce the high spatial frequencies complex processes such as electron-beam lithography and reactive ion etching are needed. We show in this paper that sinusoidal holographic gratings in photoresist exhibit also a strong phase ret even at relatively long periods. L EXPERIMENTAL MEASUREMENTS To obtain the phase retardation of a lower frequency ( period A ) grating a simple setup as used by Enger and 2 can be applied. In our case however there are three measurements necessary to obtain the phase retardation because transmission of the two perpendicularly polarized beams is different from each other. I GRATING PRODUCTION grating 2 3 4 5 6 7 8 9 period (pmj 0. 74 0. 74 0. 61 0. 54 0. 46 0. 32 0. 54 0. 54 0. 54 ne (sec) 60

  12. Surface mount component jig

    DOEpatents

    Kronberg, James W.

    1990-08-07

    A device for bending and trimming the pins of a dual-inline-package component and the like for surface mounting rather than through mounting to a circuit board comprises, in a first part, in pin cutter astride a holder having a recess for holding the component, a first spring therebetween, and, in a second part, two flat members pivotally interconnected by a hinge and urged to an upward peaked position from a downward peaked position by a second spring. As a downward force is applied to the pin cutter it urges the holder downward, assisted by the first spring and a pair of ridges riding on shoulders of the holder, to carry the component against the upward peaked flat members which guide the pins outwardly. As the holder continues downwardly, the flat members pivot to the downward peaked position bending the pins upwardly against the sides of the holder. When the downward movement is met with sufficient resistance, the ridges of the pin cutter ride over the holder's shoulders to continue downward to cut any excess length of pin.

  13. Energetic component treatability study

    SciTech Connect

    Gildea, P.D.; Brandon, S.L.; Brown, B.G.

    1997-11-01

    The effectiveness of three environmentally sound processes for small energetic component disposal was examined experimentally in this study. The three destruction methods, batch reactor supercritical water oxidation, sodium hydroxide base hydrolysis and calcium carbonate cookoff were selected based on their potential for producing a clean solid residue and minimum release of toxic gases after component detonation. The explosive hazard was destroyed by all three processes. Batch supercritical water oxidation destroyed both the energetics and organics. Further development is desired to optimize process parameters. Sodium hydroxide base hydrolysis and calcium carbonate cookoff results indicated the potential for scrubbing gaseous detonation products. Further study and testing are needed to quantify the effectiveness of these later two processes for full-scale munition destruction. The preliminary experiments completed in this study have demonstrated the promise of these three processes as environmentally sound technologies for energetic component destruction. Continuation of these experimental programs is strongly recommended to optimize batch supercritical water oxidation processing, and to fully develop the sodium hydroxide base hydrolysis and calcium carbonate cookoff technologies.

  14. Inkjet deposited circuit components

    NASA Astrophysics Data System (ADS)

    Bidoki, S. M.; Nouri, J.; Heidari, A. A.

    2010-05-01

    All-printed electronics as a means of achieving ultra-low-cost electronic circuits has attracted great interest in recent years. Inkjet printing is one of the most promising techniques by which the circuit components can be ultimately drawn (i.e. printed) onto the substrate in one step. Here, the inkjet printing technique was used to chemically deposit silver nanoparticles (10-200 nm) simply by ejection of silver nitrate and reducing solutions onto different substrates such as paper, PET plastic film and textile fabrics. The silver patterns were tested for their functionality to work as circuit components like conductor, resistor, capacitor and inductor. Different levels of conductivity were achieved simply by changing the printing sequence, inks ratio and concentration. The highest level of conductivity achieved by an office thermal inkjet printer (300 dpi) was 5.54 × 105 S m-1 on paper. Inkjet deposited capacitors could exhibit a capacitance of more than 1.5 nF (parallel plate 45 × 45 mm2) and induction coils displayed an inductance of around 400 µH (planar coil 10 cm in diameter). Comparison of electronic performance of inkjet deposited components to the performance of conventionally etched items makes the technique highly promising for fabricating different printed electronic devices.

  15. Method and apparatus for component separation using microwave energy

    DOEpatents

    Morrow, Marvin S.; Schechter, Donald E.; Calhoun, Jr., Clyde L.

    2001-04-03

    A method for separating and recovering components includes the steps of providing at least a first component bonded to a second component by a microwave absorbent adhesive bonding material at a bonding area to form an assembly, the bonding material disposed between the components. Microwave energy is directly and selectively applied to the assembly so that substantially only the bonding material absorbs the microwave energy until the bonding material is at a debonding state. A separation force is applied while the bonding material is at the debonding state to permit disengaging and recovering the components. In addition, an apparatus for practicing the method includes holders for the components.

  16. Direct to Digital Holography

    SciTech Connect

    Bingham, P.R.; Tobin, K.W.

    2007-09-30

    In this Cooperative Research and Development Agreement (CRADA), Oak Ridge National Laboratory (ORNL) assisted nLine Corporation of Austin, TX in the development of prototype semiconductor wafer inspection tools based on the direct-to-digital holographic (DDH) techniques invented at ORNL. Key components of this work included, testing of DDH for detection of defects in High Aspect Ratio (HAR) structures, development of image processing techniques to enhance detection capabilities through the use of both phase and intensity, and development of methods for autofocus on the DDH tools.

  17. Precision in the perception of direction of a moving pattern

    NASA Technical Reports Server (NTRS)

    Stone, Leland S.

    1988-01-01

    The precision of the model of pattern motion analysis put forth by Adelson and Movshon (1982) who proposed that humans determine the direction of a moving plaid (the sum of two sinusoidal gratings of different orientations) in two steps is qualitatively examined. The volocities of the grating components are first estimated, then combined using the intersection of constraints to determine the velocity of the plaid as a whole. Under the additional assumption that the noise sources for the component velocities are independent, an approximate expression can be derived for the precision in plaid direction as a function of the precision in the speed and direction of the components. Monte Carlo simulations verify that the expression is valid to within 5 percent over the natural range of the parameters. The expression is then used to predict human performance based on available estimates of human precision in the judgment of single component speed. Human performance is predicted to deteriorate by a factor of 3 as half the angle between the wavefronts (theta) decreases from 60 to 30 deg, but actual performance does not. The mean direction discrimination for three human observers was 4.3 plus or minus 0.9 deg (SD) for theta = 60 deg and 5.9 plus or minus 1.2 for theta = 30 deg. This discrepancy can be resolved in two ways. If the noises in the internal representations of the component speeds are smaller than the available estimates or if these noises are not independent, then the psychophysical results are consistent with the Adelson-Movshon hypothesis.

  18. Highly directional thermal emitter

    DOEpatents

    Ribaudo, Troy; Shaner, Eric A; Davids, Paul; Peters, David W

    2015-03-24

    A highly directional thermal emitter device comprises a two-dimensional periodic array of heavily doped semiconductor structures on a surface of a substrate. The array provides a highly directional thermal emission at a peak wavelength between 3 and 15 microns when the array is heated. For example, highly doped silicon (HDSi) with a plasma frequency in the mid-wave infrared was used to fabricate nearly perfect absorbing two-dimensional gratings structures that function as highly directional thermal radiators. The absorption and emission characteristics of the HDSi devices possessed a high degree of angular dependence for infrared absorption in the 10-12 micron range, while maintaining high reflectivity of solar radiation (.about.64%) at large incidence angles.

  19. Hydrocarbon components in carbonaceous meteorites

    NASA Astrophysics Data System (ADS)

    Kissin, Y. V.

    2003-05-01

    Currently, the presence of free n-alkanes and isoprenoid alkanes in carbonaceous meteorites is usually explained either by microbial contamination during the period between the meteorite fall and collection or by contamination from the environment of analytical laboratories and museums. The goal of this research was to repeat analysis of hydrocarbon components in meteorites and to investigate possible meteorite contamination routes discussed in the literature. Experimental analysis of free organic constituents in five carbonaceous meteorites by infrared spectroscopy (IR) and gas chromatographic (GC) methods confirmed the presence of extractable aliphatic components, n-alkanes in the C 15H 32-C 27H 56 range and isoprenoid alkanes (phytane, pristane, and norpristane), in some of these meteorites. The contents of these compounds vary depending on the source. Insoluble organic components of two meteorites (meteorite kerogens) were isolated, and their composition was analyzed by IR and cracking/GC methods. Comparison with the data on several terrestrial contamination sources proposed in the literature shows that the presence of free saturated hydrocarbons in meteorites and the composition of the meteorite kerogen could not be explained either by microbial contamination or by contamination from the laboratory environment. The types of the hydrocarbons in meteorites resemble those typical of ancient terrestrial deposits of organic-rich sediments, except for the absence of lighter hydrocarbons, which apparently slowly evaporated in space, and multi-ring naphthenic compounds of the biologic origin, steranes, terpanes, etc. The prevailing current explanation for the presence of free linear saturated hydrocarbons in carbonaceous meteorites, apart from contamination, is the abiotic route from hydrogen and carbon monoxide. However, the data on the structure of meteorite kerogens require a search for different routes that initially produce complex polymeric structures containing

  20. Direct insolation models

    SciTech Connect

    Bird, R.; Hulstrom, R.L.

    1980-01-01

    Several recently published models of the direct component of the broadband insolation are compared for clear sky conditions. The comparison includes seven simple models and one rigorous model that is used as a basis for determining accuracy. Where possible, the comparison is made between the results of each model for each atmospheric constituent (H/sub 2/O, CO/sub 2/, O/sub 3/, O/sub 2/, aerosol and molecular scattering) separately as well as for the combined effect of all of the constituents. Two optimum simple models of varying degrees of complexity are developed as a result of this comparison. The study indicates: aerosols dominate the attenuation of the direct beam for reasonable atmospheric conditions; molecular scattering is next in importance; water vapor is an important absorber; and carbon dioxide and oxygen are relatively unimportant as attenuators of the broadband solar energy.