Sample records for tiling dynamical systems

  1. Modal analysis and dynamic stresses for acoustically excited Shuttle insulation tiles

    NASA Technical Reports Server (NTRS)

    Ojalvo, I. U.; Ogilvie, P. I.

    1976-01-01

    The thermal protection system of the Space Shuttle consists of thousands of separate insulation tiles, of varying thicknesses, bonded to the orbiter's surface through a soft strain-isolation pad which is bonded, in turn, to the vehicle's stiffened metallic skin. A modal procedure for obtaining the acoustically induced RMS stress in these comparatively thick tiles is described. The modes employed are generated by a previously developed iterative procedure which converges rapidly for the combined system of tiles and primary structure considered. Each tile is idealized by several hundred three-dimensional finite elements and all tiles on a given panel interact dynamically. Acoustic response results from the present analyses are presented. Comparisons with other analytical results and measured modal data for a typical Shuttle panel, both with and without tiles, are made, and the agreement is good.

  2. Nonlinear dynamic phenomena in the space shuttle thermal protection system

    NASA Technical Reports Server (NTRS)

    Housner, J. M.; Edighoffer, H. H.; Park, K. C.

    1981-01-01

    The development of an analysis for examining the nonlinear dynamic phenomena arising in the space shuttle orbiter tile/pad thermal protection system is presented. The tile/pad system consists of ceramic tiles bonded to the aluminum skin of the orbiter through a thin nylon felt pad. The pads are a soft nonlinear material which permits large strains and displays both hysteretic and nonlinear viscous damping. Application of the analysis to a square tile subjected to transverse sinusoidal motion of the orbiter skin is presented and the following nonlinear dynamic phenomena are considered: highly distorted wave forms, amplitude-dependent resonant frequencies which initially decrease and then increase with increasing amplitude of motion, magnification of substrate motion which is higher than would be expected in a similarly highly damped linear system, and classical parametric resonance instability.

  3. Acousto-optic signature analysis for inspection of the orbiter thermal protection tile bonds

    NASA Technical Reports Server (NTRS)

    Rodriguez, Julio G.; Tow, D. M.; Barna, B. A.

    1990-01-01

    The goal of this research is to develop a viable NDE technique for the inspection of orbiter thermal protection system (TPS) tile bonds. Phase 2, discussed here, concentrated on developing an empirical understanding of the bonded and unbonded vibration signatures of acreage tiles. Controlled experiments in the laboratory have provided useful information on the dynamic response of TPS tiles. It has been shown that several signatures are common to all the pedigree tiles. This degree of consistency in the tile-SIP (strain isolation pad) dynamic response proves that an unbond can be detected for a known tile and establish the basis for extending the analysis capability to arbitrary tiles for which there are no historical data. The field tests of the noncontacting laser acoustic sensor system, conducted at the Kennedy Space Center (KSC), investigated the vibrational environment of the Orbiter Processing Facility (OPF) and its effect on the measurement and analysis techniques being developed. The data collected showed that for orbiter locations, such as the body flap and elevon, the data analysis scheme, and/or the sensor, will require modification to accommodate the ambient motion. Several methods were identified for accomplishing this, and a solution is seen as readily achievable. It was established that the tile response was similar to that observed in the laboratory. Of most importance, however, is that the field environment will not affect the physics of the dynamic response that is related to bond condition. All of this information is fundamental to any future design and development of a prototype system.

  4. Nonlinear dynamic response of a uni-directional model for the tile/pad space shuttle thermal protection system

    NASA Technical Reports Server (NTRS)

    Housner, J. M.; Edighoffer, H. H.; Park, K. C.

    1980-01-01

    A unidirectional analysis of the nonlinear dynamic behavior of the space shuttle tile/pad thermal protection system is developed and examined for imposed sinusoidal and random motions of the shuttle skin and/or applied tile pressure. The analysis accounts for the highly nonlinear stiffening hysteresis and viscous behavior of the pad which joins the tile to the shuttle skin. Where available, experimental data are used to confirm the validity of the analysis. Both analytical and experimental studies reveal that the system resonant frequency is very high for low amplitude oscillations but decreases rapidly to a minimum value with increasing amplitude. Analytical studies indicate that with still higher amplitude the resonant frequency increases slowly. The nonlinear pad is also responsible for the analytically and experimentally observed distorted response wave shapes having high sharp peaks when the system is subject to sinusoidal loads. Furthermore, energy dissipation in the pad is studied analytically and it is found that the energy dissipated is sufficiently high to cause rapid decay of dynamic transients. Nevertheless, the sharp peaked nonlinear responses of the system lead to higher magnification factors than would be expected in such a highly damped linear system.

  5. A method for the dynamic and thermal stress analysis of space shuttle surface insulation

    NASA Technical Reports Server (NTRS)

    Ojalvo, I. U.; Levy, A.; Austin, F.

    1975-01-01

    The thermal protection system of the space shuttle consists of thousands of separate insulation tiles bonded to the orbiter's surface through a soft strain-isolation layer. The individual tiles are relatively thick and possess nonuniform properties. Therefore, each is idealized by finite-element assemblages containing up to 2500 degrees of freedom. Since the tiles affixed to a given structural panel will, in general, interact with one another, application of the standard direct-stiffness method would require equation systems involving excessive numbers of unknowns. This paper presents a method which overcomes this problem through an efficient iterative procedure which requires treatment of only a single tile at any given time. Results of associated static, dynamic, and thermal stress analyses and sufficient conditions for convergence of the iterative solution method are given.

  6. Beautiful Math, Part 5: Colorful Archimedean Tilings from Dynamical Systems.

    PubMed

    Ouyang, Peichang; Zhao, Weiguo; Huang, Xuan

    2015-01-01

    The art of tiling originated very early in the history of civilization. Almost every known human society has made use of tilings in some form or another. In particular, tilings using only regular polygons have great visual appeal. Decorated regular tilings with continuous and symmetrical patterns were widely used in decoration field, such as mosaics, pavements, and brick walls. In science, these tilings provide inspiration for synthetic organic chemistry. Building on previous CG&A “Beautiful Math” articles, the authors propose an invariant mapping method to create colorful patterns on Archimedean tilings (1-uniform tilings). The resulting patterns simultaneously have global crystallographic symmetry and local cyclic or dihedral symmetry.

  7. Some space shuttle tile/strain-isolator-pad sinusoidal vibration tests

    NASA Technical Reports Server (NTRS)

    Miserentino, R.; Pinson, L. D.; Leadbetter, S. A.

    1980-01-01

    Vibration tests were performed on the tile/strain-isolator-pad system used as thermal protection for the space shuttle orbiter. Experimental data on normal and in-plane vibration response and damping properties are presented. Three test specimens exhibited shear type motion during failures that occurred in the tile near the tile/strain-isolator-pad bond-line. A dynamic instability is described which has large in-plane motion at a frequency one-half that of the nominal driving frequency. Analysis shows that this phenomenon is a parametric response.

  8. CFD-Predicted Tile Heating Bump Factors Due to Tile Overlay Repairs

    NASA Technical Reports Server (NTRS)

    Lessard, Victor R.

    2006-01-01

    A Computational Fluid Dynamics investigation of the Orbiter's Tile Overlay Repair (TOR) is performed to assess the aeroheating Damage Assessment Team's (DAT) existing heating correlation method for protuberance interference heating on the surrounding thermal protection system. Aerothermodynamic heating analyses are performed for TORs at the design reference damage locations body points 1800 and 1075 for a Mach 17.9 and a=39deg STS-107 flight trajectory point with laminar flow. Six different cases are considered. The computed peak heating bump factor on the surrounding tiles are below the DAT's heating bump factor values for smooth tile cases. However, for the uneven tiles cases the peak interference heating is shown to be considerably higher than the existing correlation prediction.

  9. NDE of the space shuttle orbiter thermal protection system: Phase 2 final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tow, D.M.; Barna, B.A.; Rodriguez, J.G.

    1989-03-01

    Research continued on the development of a nondestructive evaluation technique for inspecting bonds on the space shuttle orbiter thermal protection system tiles. The approach taken uses a noncontacting laser sensor to measure the vibrational response of bonded tiles to acoustical excitation. Laboratory work concentrated on investigating the dynamic response of ''acreage'' tiles, i.e., tiles covering the underside of the orbiter, all approximately square. A number of promising unbond signatures have been identified in the time and frequency domain response. Field tests were conducted to study environmental effects on the techniques being developed. The ambient motion of the orbiter was foundmore » to be larger than expected, necessitating modifications to current techniques. 2 refs., 21 figs., 1 tab.« less

  10. Parametric Analytical Studies for the Nonlinear Dynamic Response of the Tile/Pad Space Shuttle Thermal Protection System

    NASA Technical Reports Server (NTRS)

    Edighoffer, H.

    1981-01-01

    The studies examined for imposed sinusoidal and random motions of the shuttle skin and/or applied tile pressure. Studies are performed using the computer code DYNOTA which takes into account the highly nonlinear stiffening hysteresis and viscous behavior of the pad joining the tile to the shuttle skin. Where available, experimental data are used to confirm the validity of the analysis. Both analytical and experimental studies reveal that the system resonant frequency is very high for low amplitude oscillations but decreases rapidly to a minimum value with increasing amplitude.

  11. Wavefunctions, quantum diffusion, and scaling exponents in golden-mean quasiperiodic tilings.

    PubMed

    Thiem, Stefanie; Schreiber, Michael

    2013-02-20

    We study the properties of wavefunctions and the wavepacket dynamics in quasiperiodic tight-binding models in one, two, and three dimensions. The atoms in the one-dimensional quasiperiodic chains are coupled by weak and strong bonds aligned according to the Fibonacci sequence. The associated d-dimensional quasiperiodic tilings are constructed from the direct product of d such chains, which yields either the hypercubic tiling or the labyrinth tiling. This approach allows us to consider fairly large systems numerically. We show that the wavefunctions of the system are multifractal and that their properties can be related to the structure of the system in the regime of strong quasiperiodic modulation by a renormalization group (RG) approach. We also study the dynamics of wavepackets to get information about the electronic transport properties. In particular, we investigate the scaling behaviour of the return probability of the wavepacket with time. Applying again the RG approach we show that in the regime of strong quasiperiodic modulation the return probability is governed by the underlying quasiperiodic structure. Further, we also discuss lower bounds for the scaling exponent of the width of the wavepacket and propose a modified lower bound for the absolute continuous regime.

  12. Controlled Nucleation and Growth of DNA Tile Arrays within Prescribed DNA Origami Frames and Their Dynamics

    PubMed Central

    2015-01-01

    Controlled nucleation of nanoscale building blocks by geometrically defined seeds implanted in DNA nanoscaffolds represents a unique strategy to study and understand the dynamic processes of molecular self-assembly. Here we utilize a two-dimensional DNA origami frame with a hollow interior and selectively positioned DNA hybridization seeds to control the self-assembly of DNA tile building blocks, where the small DNA tiles are directed to fill the interior of the frame through prescribed sticky end interactions. This design facilitates the construction of DNA origami/array hybrids that adopt the overall shape and dimensions of the origami frame, forming a 2D array in the core consisting of a large number of simple repeating DNA tiles. The formation of the origami/array hybrid was characterized with atomic force microscopy, and the nucleation dynamics were monitored by serial AFM scanning and fluorescence spectroscopy, which revealed faster kinetics of growth within the frame as compared to growth without the presence of a frame. Our study provides insight into the fundamental behavior of DNA-based self-assembling systems. PMID:24575893

  13. Performance of LI-1542 reusable surface insulation system in a hypersonic stream

    NASA Technical Reports Server (NTRS)

    Hunt, L. R.; Shideler, J. L.; Weinstein, I.

    1976-01-01

    The thermal and structural performance LI-1542 reusable surface insulation (RSI) tiles was investigated. The test panel was designed to represent part of the surface structure on a space shuttle orbiter fuselage along a 1250 K isotherm. Aerothermal tests were conducted at a free-stream Mach number of 6.6, a total temperature of 1820 K, Reynolds numbers of 2 millon and 5 million per meter, and dynamic pressures of 26 and 65 kPa. The RSI tiles demonstrated good thermal protection and structural integrity. High temperatures were caused by misalinement in tile height, offset the tile longitudinal alinement, and leakage around thermal seals when differential pressure existed across the panel. The damage tolerance of LI-1542 RSI appeared high. The tile coating crazed early in the test program, but this did not effect the tile integrity. Erosion of the tile edges occurred at forward-facing steps and at the ends of longitudinal gaps because of particle impacts and flow shear.

  14. Post Test Evaluation of HSCT Nozzle Acoustic Liner Subcomponents Subjected to a Hot Acoustic Durability Test

    NASA Technical Reports Server (NTRS)

    Verrilli, Michael J.; Lee, Kuan

    2008-01-01

    The acoustic liner system designed for use in the High Speed Civil Transport (HSCT) was tested in a thermal-acoustic environment. Five ceramic matrix composite (CMC) acoustic tile configurations, five bulk acoustic absorbers, and one thermal protection system design were tested. The CMC acoustic tiles were subjected to two 2 3/4 hr ambient temperature acoustic exposures to measure their dynamic response. One exposure was conducted on the tiles alone and the second exposure included the tiles and the T-foam bulk absorber. The measured tile RMS strains were small. With or without the T-foam absorber, the dynamic strains were below strain levels that would cause damage during fatigue loading. After the ambient exposure, a 75-hr durability test of the entire acoustic liner system was conducted using a thermal-acoustic cycle that approximated the anticipated service cycle. Acoustic loads up to 139 dB/Hz and temperatures up to 1670 F (910 C) were employed during this 60 cycle test. During the durability test, the CMC tiles were exposed to temperatures up to 1780 F and a transient through thickness gradient up to 490 F. The TPS peak temperatures on the hot side of the panels ranged from 750 to 1000 F during the 60 cycles. The through thickness delta T ranged from 450 to 650 F, varying with TPS location and cycle number. No damage, such as cracks or chipping, was observed in the CMC tiles after completion of the testing. However, on tile warped during the durability test and was replaced after 43 or 60 cycles. No externally observed damage was found in this tile. No failure of the CMC fasteners occurred, but damage was observed. Cracks and missing material occurred, only in the fastener head region. No indication of damage was observed in the T-foam acoustic absorbers. The SiC foam acoustic absorber experienced damage after about 43 cycles. Cracking in the TPS occurred around the attachment holes and under a vent. In spite of the development of damage, the TPS maintained its insulative capability throughout the durability test. The durability test results demonstrate damage-tolerant CMC tile, CMC fastener, TPS, and T-foam absorber designs for the combined thermal and acoustic engine nozzle environment.

  15. Impact of Tile Drainage on the Distribution of Concentration and Age of Inorganic Soil Nitrogen.

    NASA Astrophysics Data System (ADS)

    Woo, D.; Kumar, P.

    2017-12-01

    Extensive network of tile drainage network across the Midwestern United States, northern Europe and other regions of the world have enhanced agricultural productivity. Because of its impact on sub-surface flow patterns and moisture and temperature dynamics, it controls the nitrogen cycle in agricultural systems, and its influence on nitrogen dynamics plays a key role in determining the short- and long-term evolution of soil inorganic nitrogen concentration and age. The spatial mapping of nitrogen concentration and age under tile-drained fields has, therefore, the potential to open up novel solution to the vexing challenge of reducing environmental impacts while at the same time maintaining agricultural productivity. The objective of this study is to explore the impacts of tile drains on the age dynamics of nitrate, immobile ammonium, mobile ammonia/um, and non-reactive tracer (such as chloride) by implementing two mobile interacting pore domains to capture matrix and preferential flow paths in a coupled ecohydrology and biogeochemistry model, Dhara. We applied this model to an agricultural farm supporting a corn-soybean rotation in the Midwestern United States. It should be expected that the installation of tile drains decrease the age of soil nutrient due to nutrient losses through tile drainage. However, an increase in the age of mobile ammonia/um is observed in contrast to the cases for nitrate, immobile ammonium, and non-reactive tracer. These results arise because the depletion of mobile ammonia/um due to tile drainage causes a high mobility flux from immobile ammonium to mobile ammonia/um, which also carries a considerable amount of relatively old age of immobile ammonium to mobile ammonia/um. In addition, the ages of nitrate and mobile ammonia/um in tile drainage range from 1 to 3 years, and less than a year, respectively, implying that not considering age transformations between nitrogen species would result in substantial underestimation of nitrogen ages, possibly leading to an erroneous conclusion.

  16. Tile Drainage Expansion Detection using Satellite Soil Moisture Dynamics

    NASA Astrophysics Data System (ADS)

    Jacobs, J. M.; Cho, E.; Jia, X.

    2017-12-01

    In the past two decades, tile drainage installation has accelerated throughout the Red River of the North Basin (RRB) in parts of western Minnesota, eastern North Dakota, and a small area of northeastern South Dakota, because the flat topography and low-permeability soils in this region necessitated the removal of excess water to improve crop production. Interestingly, streamflow in the Red River has markedly increased and six of 13 major floods during the past century have occurred since the late 1990s. It has been suggested that the increase in RRB flooding could be due to change in agricultural practices, including extensive tile drainage installation. Reliable information on existing and future tile drainage installation is greatly needed to capture the rapid extension of tile drainage systems and to locate tile drainage systems in the north central U.S. including the RRB region. However, there are few reliable data of tile drainage installation records, except tile drainage permit records in the Bois de Sioux watershed (a sub-basin in southern part of the RRB where permits are required for tile drainage installation). This study presents a tile drainage expansion detection method based on a physical principle that the soil-drying rate may increase with increasing tile drainage for a given area. In order to capture the rate of change in soil drying rate with time over entire RRB (101,500 km2), two satellite-based microwave soil moisture records from the Advanced Microwave Scanning Radiometer for Earth Observing System (AMSR-E) and AMSR2 were used during 2002 to 2016. In this study, a sub-watershed level (HUC10) potential tile drainage growth map was developed and the results show good agreement with tile drainage permit records of six sub-watersheds in the Bois de Sioux watershed. Future analyses will include improvement of the potential tile drainage map through additional information using optical- and thermal-based sensor products and evaluation of its hydrological impacts on intensity, duration, and frequency of extreme streamflow from watershed to basin scale.

  17. Performance of a mullite reusable surface insulation system in a hypersonic stream

    NASA Technical Reports Server (NTRS)

    Hunt, L. R.

    1976-01-01

    The thermal and structural performance of a large panel of mullite reusable surface insulation (RSI) tiles was determined by a series of aerothermal tests in the Langley 8-foot high-temperature structures tunnel. The test panel was designed to represent a portion of the surface structure on a space shuttle orbiter fuselage along a 1,150 K isotherm with the mullite tile system bonded directly to the primary structure. Aerothermal tests were conducted at a free-stream Mach number of 6.7, a total temperature of 1,880 K, a unit Reynolds number of 4.6 million per meter, and dynamic pressure of 62 kPa. The thermal response of the mullite tile was as predicted, and the bond-line temperature did not exceed the design level of 570 K during a typical entry-heat cycle. Geometric irregularities of the tile gaps affected the tile edge temperatures when exposed to hypersonic flow. The tile coating demonstrated good toughness to particle impacts, but the coating cracked and flaked with thermal cycles. The gap filler of woven silica fibers appeared to hinder flow penetration into the gaps and withstood the flow shear of the present tests.

  18. Integrating DNA strand-displacement circuitry with DNA tile self-assembly

    PubMed Central

    Zhang, David Yu; Hariadi, Rizal F.; Choi, Harry M.T.; Winfree, Erik

    2013-01-01

    DNA nanotechnology has emerged as a reliable and programmable way of controlling matter at the nanoscale through the specificity of Watson–Crick base pairing, allowing both complex self-assembled structures with nanometer precision and complex reaction networks implementing digital and analog behaviors. Here we show how two well-developed frameworks, DNA tile self-assembly and DNA strand-displacement circuits, can be systematically integrated to provide programmable kinetic control of self-assembly. We demonstrate the triggered and catalytic isothermal self-assembly of DNA nanotubes over 10 μm long from precursor DNA double-crossover tiles activated by an upstream DNA catalyst network. Integrating more sophisticated control circuits and tile systems could enable precise spatial and temporal organization of dynamic molecular structures. PMID:23756381

  19. Dynamic origin of segment magnetization reversal in thin-film Penrose tilings

    NASA Astrophysics Data System (ADS)

    Montoncello, F.; Giovannini, L.; Farmer, B.; De Long, L.

    2017-02-01

    We investigate the low-frequency spin wave dynamics involved in the magnetization reversal of a Penrose P2 tiling using the dynamical matrix method. This system consists of a two-dimensional, connected wire network of elongated thin-film segments, whose complete reversal occurs as a cascade of successive local segment reversals. Using soft mode theory, we interpret the reversal of an individual segment as a first order magnetic transition, in which magnetization curve of the system suffers a small discontinuity. Near this discontinuity a specific mode of the spin wave spectrum goes soft (i.e., its frequency goes to zero), triggering a local instability of the magnetization. We show that this mode is localized, and is at the origin of the local reversal. We discuss the correlation of the mode spatial profile with the ;reversal mechanism;, which is the passage of a domain wall through the segment. This process differs from reversal in periodic square or honeycomb artificial spin ices, where a cascade of reversing segments (e.g., ;Dirac string;) follows an extended (though irregular) path across the sample; here the spatial distribution of successive segment reversals is discontinuous, but strictly associated with the area where a soft mode is localized. The migration of the localization area across the P2 tiling (during reversal in decreasing applied fields) depends on changes in the internal effective field map. We discuss these results in the context of spin wave localization due to the unique topology of the P2 tiling.

  20. Dynamic Simulation of 1D Cellular Automata in the Active aTAM.

    PubMed

    Jonoska, Nataša; Karpenko, Daria; Seki, Shinnosuke

    2015-07-01

    The Active aTAM is a tile based model for self-assembly where tiles are able to transfer signals and change identities according to the signals received. We extend Active aTAM to include deactivation signals and thereby allow detachment of tiles. We show that the model allows a dynamic simulation of cellular automata with assemblies that do not record the entire computational history but only the current updates of the states, and thus provide a way for (a) algorithmic dynamical structural changes in the assembly and (b) reusable space in self-assembly. The simulation is such that at a given location the sequence of tiles that attach and detach corresponds precisely to the sequence of states the synchronous cellular automaton generates at that location.

  1. Dynamic Simulation of 1D Cellular Automata in the Active aTAM

    PubMed Central

    Jonoska, Nataša; Karpenko, Daria; Seki, Shinnosuke

    2016-01-01

    The Active aTAM is a tile based model for self-assembly where tiles are able to transfer signals and change identities according to the signals received. We extend Active aTAM to include deactivation signals and thereby allow detachment of tiles. We show that the model allows a dynamic simulation of cellular automata with assemblies that do not record the entire computational history but only the current updates of the states, and thus provide a way for (a) algorithmic dynamical structural changes in the assembly and (b) reusable space in self-assembly. The simulation is such that at a given location the sequence of tiles that attach and detach corresponds precisely to the sequence of states the synchronous cellular automaton generates at that location. PMID:27789918

  2. Global Swath and Gridded Data Tiling

    NASA Technical Reports Server (NTRS)

    Thompson, Charles K.

    2012-01-01

    This software generates cylindrically projected tiles of swath-based or gridded satellite data for the purpose of dynamically generating high-resolution global images covering various time periods, scaling ranges, and colors called "tiles." It reconstructs a global image given a set of tiles covering a particular time range, scaling values, and a color table. The program is configurable in terms of tile size, spatial resolution, format of input data, location of input data (local or distributed), number of processes run in parallel, and data conditioning.

  3. A scalable approach to solving dense linear algebra problems on hybrid CPU-GPU systems

    DOE PAGES

    Song, Fengguang; Dongarra, Jack

    2014-10-01

    Aiming to fully exploit the computing power of all CPUs and all graphics processing units (GPUs) on hybrid CPU-GPU systems to solve dense linear algebra problems, in this paper we design a class of heterogeneous tile algorithms to maximize the degree of parallelism, to minimize the communication volume, and to accommodate the heterogeneity between CPUs and GPUs. The new heterogeneous tile algorithms are executed upon our decentralized dynamic scheduling runtime system, which schedules a task graph dynamically and transfers data between compute nodes automatically. The runtime system uses a new distributed task assignment protocol to solve data dependencies between tasksmore » without any coordination between processing units. By overlapping computation and communication through dynamic scheduling, we are able to attain scalable performance for the double-precision Cholesky factorization and QR factorization. Finally, our approach demonstrates a performance comparable to Intel MKL on shared-memory multicore systems and better performance than both vendor (e.g., Intel MKL) and open source libraries (e.g., StarPU) in the following three environments: heterogeneous clusters with GPUs, conventional clusters without GPUs, and shared-memory systems with multiple GPUs.« less

  4. A scalable approach to solving dense linear algebra problems on hybrid CPU-GPU systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Song, Fengguang; Dongarra, Jack

    Aiming to fully exploit the computing power of all CPUs and all graphics processing units (GPUs) on hybrid CPU-GPU systems to solve dense linear algebra problems, in this paper we design a class of heterogeneous tile algorithms to maximize the degree of parallelism, to minimize the communication volume, and to accommodate the heterogeneity between CPUs and GPUs. The new heterogeneous tile algorithms are executed upon our decentralized dynamic scheduling runtime system, which schedules a task graph dynamically and transfers data between compute nodes automatically. The runtime system uses a new distributed task assignment protocol to solve data dependencies between tasksmore » without any coordination between processing units. By overlapping computation and communication through dynamic scheduling, we are able to attain scalable performance for the double-precision Cholesky factorization and QR factorization. Finally, our approach demonstrates a performance comparable to Intel MKL on shared-memory multicore systems and better performance than both vendor (e.g., Intel MKL) and open source libraries (e.g., StarPU) in the following three environments: heterogeneous clusters with GPUs, conventional clusters without GPUs, and shared-memory systems with multiple GPUs.« less

  5. Molecular ping-pong Game of Life on a two-dimensional DNA origami array.

    PubMed

    Jonoska, N; Seeman, N C

    2015-07-28

    We propose a design for programmed molecular interactions that continuously change molecular arrangements in a predesigned manner. We introduce a model where environmental control through laser illumination allows platform attachment/detachment oscillations between two floating molecular species. The platform is a two-dimensional DNA origami array of tiles decorated with strands that provide both, the floating molecular tiles to attach and to pass communicating signals to neighbouring array tiles. In particular, we show how algorithmic molecular interactions can control cyclic molecular arrangements by exhibiting a system that can simulate the dynamics similar to two-dimensional cellular automata on a DNA origami array platform. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  6. DNAzyme-Based Logic Gate-Mediated DNA Self-Assembly.

    PubMed

    Zhang, Cheng; Yang, Jing; Jiang, Shuoxing; Liu, Yan; Yan, Hao

    2016-01-13

    Controlling DNA self-assembly processes using rationally designed logic gates is a major goal of DNA-based nanotechnology and programming. Such controls could facilitate the hierarchical engineering of complex nanopatterns responding to various molecular triggers or inputs. Here, we demonstrate the use of a series of DNAzyme-based logic gates to control DNA tile self-assembly onto a prescribed DNA origami frame. Logic systems such as "YES," "OR," "AND," and "logic switch" are implemented based on DNAzyme-mediated tile recognition with the DNA origami frame. DNAzyme is designed to play two roles: (1) as an intermediate messenger to motivate downstream reactions and (2) as a final trigger to report fluorescent signals, enabling information relay between the DNA origami-framed tile assembly and fluorescent signaling. The results of this study demonstrate the plausibility of DNAzyme-mediated hierarchical self-assembly and provide new tools for generating dynamic and responsive self-assembly systems.

  7. Local dynamic range compensation for scanning electron microscope imaging system.

    PubMed

    Sim, K S; Huang, Y H

    2015-01-01

    This is the extended project by introducing the modified dynamic range histogram modification (MDRHM) and is presented in this paper. This technique is used to enhance the scanning electron microscope (SEM) imaging system. By comparing with the conventional histogram modification compensators, this technique utilizes histogram profiling by extending the dynamic range of each tile of an image to the limit of 0-255 range while retains its histogram shape. The proposed technique yields better image compensation compared to conventional methods. © Wiley Periodicals, Inc.

  8. Performance of LI-1542 reusable surface insulation system in a hypersonic stream

    NASA Technical Reports Server (NTRS)

    Hunt, L. R.; Bohon, H. L.

    1974-01-01

    The thermal and structural performance of a large panel of LI-1542 reusable surface insulation tiles was determined by a series of cyclic heating tests using radiant lamps and aerothemal tests in the Langley 8-foot high-temperature structures tunnel. Aerothermal tests were conducted at a free-stream Mach number of 6.6, a total temperature of 1830 K, Reynolds numbers of 2.0 and 4,900,000 per meter, and dynamic pressures of 29 and 65 kPa. The results suggest that pressure gradients in gaps and flow impingement on the header walls at the end of longitudinal gaps are sources for increased gap heating. Temperatures higher than surface radiation equilibrium temperature were measured deep in gaps and at the header walls. Also, the damage tolerance of the LI-1542 tiles appears to be very high. Tile edge erosion rate was slow; could not be tolerated in a shuttle application. Tiles soaked with water and subjected to rapid depressurization and aerodynamic heating showed no visible evidence of damage.

  9. Experimental aerodynamic heating to simulated space shuttle tiles in laminar and turbulent boundary layers with variable flow angles at a nominal Mach number of 7. M.S. Thesis - George Washington Univ., Nov. 1983

    NASA Technical Reports Server (NTRS)

    Avery, D. E.

    1985-01-01

    The heat transfer to simulated shuttle thermal protection system tiles was investigated experimentally by using a highly instrumented metallic thin wall tile arranged with other metal tiles in a staggered tile array. Cold wall heating rate data for laminar and turbulent flow were obtained in the Langley 8 foot high Temperature Tunnel at a nominal Mach number of 7, a nominal total temperature of 3300R, a free stream unit Reynolds number from 3.4 x 10 sup 5 to 2.2 10 sup 6 per foot, and a free stream dynamic pressure from 2.1 to 9.0 psia. Experimental data are presented to illustrate the effects of flow angularity and gap width on both local peak heating and overall heating loads. For the conditions of the present study, the results show that localized and total heating are sensitive to changes in flow angle only for the test conditions of turbulent boundary layer flow with high kinetic energy and that a flow angle from 30 deg to 50 deg will minimize the local heating.

  10. An automated data management/analysis system for space shuttle orbiter tiles. [stress analysis

    NASA Technical Reports Server (NTRS)

    Giles, G. L.; Ballas, M.

    1982-01-01

    An engineering data management system was combined with a nonlinear stress analysis program to provide a capability for analyzing a large number of tiles on the space shuttle orbiter. Tile geometry data and all data necessary of define the tile loads environment accessed automatically as needed for the analysis of a particular tile or a set of tiles. User documentation provided includes: (1) description of computer programs and data files contained in the system; (2) definitions of all engineering data stored in the data base; (3) characteristics of the tile anaytical model; (4) instructions for preparation of user input; and (5) a sample problem to illustrate use of the system. Description of data, computer programs, and analytical models of the tile are sufficiently detailed to guide extension of the system to include additional zones of tiles and/or additional types of analyses

  11. Ceramic-ceramic shell tile thermal protection system and method thereof

    NASA Technical Reports Server (NTRS)

    Riccitiello, Salvatore R. (Inventor); Smith, Marnell (Inventor); Goldstein, Howard E. (Inventor); Zimmerman, Norman B. (Inventor)

    1986-01-01

    A ceramic reusable, externally applied composite thermal protection system (TPS) is proposed. The system functions by utilizing a ceramic/ceramic upper shell structure which effectively separates its primary functions as a thermal insulator and as a load carrier to transmit loads to the cold structure. The composite tile system also prevents impact damage to the atmospheric entry vehicle thermal protection system. The composite tile comprises a structurally strong upper ceramic/ceramic shell manufactured from ceramic fibers and ceramic matrix meeting the thermal and structural requirements of a tile used on a re-entry aerospace vehicle. In addition, a lightweight high temperature ceramic lower temperature base tile is used. The upper shell and lower tile are attached by means effective to withstand the extreme temperatures (3000 to 3200F) and stress conditions. The composite tile may include one or more layers of variable density rigid or flexible thermal insulation. The assembly of the overall tile is facilitated by two or more locking mechanisms on opposing sides of the overall tile assembly. The assembly may occur subsequent to the installation of the lower shell tile on the spacecraft structural skin.

  12. Direct atomic force microscopy observation of DNA tile crystal growth at the single-molecule level.

    PubMed

    Evans, Constantine G; Hariadi, Rizal F; Winfree, Erik

    2012-06-27

    While the theoretical implications of models of DNA tile self-assembly have been extensively researched and such models have been used to design DNA tile systems for use in experiments, there has been little research testing the fundamental assumptions of those models. In this paper, we use direct observation of individual tile attachments and detachments of two DNA tile systems on a mica surface imaged with an atomic force microscope (AFM) to compile statistics of tile attachments and detachments. We show that these statistics fit the widely used kinetic Tile Assembly Model and demonstrate AFM movies as a viable technique for directly investigating DNA tile systems during growth rather than after assembly.

  13. A bipedal DNA motor that travels back and forth between two DNA origami tiles.

    PubMed

    Liber, Miran; Tomov, Toma E; Tsukanov, Roman; Berger, Yaron; Nir, Eyal

    2015-02-04

    In this work, the successful operation of a dynamic DNA device constructed from two DNA origami building blocks is reported. The device includes a bipedal walker that strides back and forth between the two origami tiles. Two different DNA origami tiles are first prepared separately; they are then joined together in a controlled manner by a set of DNA strands to form a stable track in high yield as confirmed by single-molecule fluorescence (SMF). Second, a bipedal DNA motor, initially attached to one of the two origami units and operated by sequential interaction with "fuel" and "antifuel" DNA strands, moves from one origami tile to another and then back again. The operational yield, measured by SMF, was similar to that of a motor operating on a similar track embedded in a single origami tile, confirming that the transfer across the junction from one tile to the other does not result in dissociation that is any more than that of steps on a single tile. These results demonstrate that moving parts can reliably travel from one origami unit to another, and it demonstrates the feasibility of dynamic DNA molecular machines that are made of more than a single origami building block. This study is a step toward the development of motors that can stride over micrometer distances. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Impacts of Space Shuttle thermal protection system tile on F-15 aircraft vertical tile

    NASA Technical Reports Server (NTRS)

    Ko, W. L.

    1985-01-01

    Impacts of the space shuttle thermal protection system (TPS) tile on the leading edge and the side of the vertical tail of the F-15 aircraft were analyzed under different TPS tile orientations. The TPS tile-breaking tests were conducted to simulate the TPS tile impacts. It was found that the predicted tile impact forces compare fairly well with the tile-breaking forces, and the impact forces exerted on the F-15 aircraft vertical tail were relatively low because a very small fraction of the tile kinetic energy was dissipated in the impact, penetration, and fracture of the tile. It was also found that the oblique impact of the tile on the side of the F-15 aircraft vertical tail was unlikely to dent the tail surface.

  15. Harnessing Big Data to Represent 30-meter Spatial Heterogeneity in Earth System Models

    NASA Astrophysics Data System (ADS)

    Chaney, N.; Shevliakova, E.; Malyshev, S.; Van Huijgevoort, M.; Milly, C.; Sulman, B. N.

    2016-12-01

    Terrestrial land surface processes play a critical role in the Earth system; they have a profound impact on the global climate, food and energy production, freshwater resources, and biodiversity. One of the most fascinating yet challenging aspects of characterizing terrestrial ecosystems is their field-scale (˜30 m) spatial heterogeneity. It has been observed repeatedly that the water, energy, and biogeochemical cycles at multiple temporal and spatial scales have deep ties to an ecosystem's spatial structure. Current Earth system models largely disregard this important relationship leading to an inadequate representation of ecosystem dynamics. In this presentation, we will show how existing global environmental datasets can be harnessed to explicitly represent field-scale spatial heterogeneity in Earth system models. For each macroscale grid cell, these environmental data are clustered according to their field-scale soil and topographic attributes to define unique sub-grid tiles. The state-of-the-art Geophysical Fluid Dynamics Laboratory (GFDL) land model is then used to simulate these tiles and their spatial interactions via the exchange of water, energy, and nutrients along explicit topographic gradients. Using historical simulations over the contiguous United States, we will show how a robust representation of field-scale spatial heterogeneity impacts modeled ecosystem dynamics including the water, energy, and biogeochemical cycles as well as vegetation composition and distribution.

  16. Force-Induced Unravelling of DNA Origami.

    PubMed

    Engel, Megan C; Smith, David M; Jobst, Markus A; Sajfutdinow, Martin; Liedl, Tim; Romano, Flavio; Rovigatti, Lorenzo; Louis, Ard A; Doye, Jonathan P K

    2018-05-31

    The mechanical properties of DNA nanostructures are of widespread interest as applications that exploit their stability under constant or intermittent external forces become increasingly common. We explore the force response of DNA origami in comprehensive detail by combining AFM single molecule force spectroscopy experiments with simulations using oxDNA, a coarse-grained model of DNA at the nucleotide level, to study the unravelling of an iconic origami system: the Rothemund tile. We contrast the force-induced melting of the tile with simulations of an origami 10-helix bundle. Finally, we simulate a recently-proposed origami biosensor, whose function takes advantage of origami behaviour under tension. We observe characteristic stick-slip unfolding dynamics in our force-extension curves for both the Rothemund tile and the helix bundle and reasonable agreement with experimentally observed rupture forces for these systems. Our results highlight the effect of design on force response: we observe regular, modular unfolding for the Rothemund tile that contrasts with strain-softening of the 10-helix bundle which leads to catastropic failure under monotonically increasing force. Further, unravelling occurs straightforwardly from the scaffold ends inwards for the Rothemund tile, while the helix bundle unfolds more nonlinearly. The detailed visualization of the yielding events provided by simulation allows preferred pathways through the complex unfolding free-energy landscape to be mapped, as a key factor in determining relative barrier heights is the extensional release per base pair broken. We shed light on two important questions: how stable DNA nanostructures are under external forces; and what design principles can be applied to enhance stability.

  17. Tile-Image Merging and Delivering for Virtual Camera Services on Tiled-Display for Real-Time Remote Collaboration

    NASA Astrophysics Data System (ADS)

    Choe, Giseok; Nang, Jongho

    The tiled-display system has been used as a Computer Supported Cooperative Work (CSCW) environment, in which multiple local (and/or remote) participants cooperate using some shared applications whose outputs are displayed on a large-scale and high-resolution tiled-display, which is controlled by a cluster of PC's, one PC per display. In order to make the collaboration effective, each remote participant should be aware of all CSCW activities on the titled display system in real-time. This paper presents a capturing and delivering mechanism of all activities on titled-display system to remote participants in real-time. In the proposed mechanism, the screen images of all PC's are periodically captured and delivered to the Merging Server that maintains separate buffers to store the captured images from the PCs. The mechanism selects one tile image from each buffer, merges the images to make a screen shot of the whole tiled-display, clips a Region of Interest (ROI), compresses and streams it to remote participants in real-time. A technical challenge in the proposed mechanism is how to select a set of tile images, one from each buffer, for merging so that the tile images displayed at the same time on the tiled-display can be properly merged together. This paper presents three selection algorithms; a sequential selection algorithm, a capturing time based algorithm, and a capturing time and visual consistency based algorithm. It also proposes a mechanism of providing several virtual cameras on tiled-display system to remote participants by concurrently clipping several different ROI's from the same merged tiled-display images, and delivering them after compressing with video encoders requested by the remote participants. By interactively changing and resizing his/her own ROI, a remote participant can check the activities on the tiled-display effectively. Experiments on a 3 × 2 tiled-display system show that the proposed merging algorithm can build a tiled-display image stream synchronously, and the ROI-based clipping and delivering mechanism can provide individual views on the tiled-display system to multiple remote participants in real-time.

  18. Physical principles for DNA tile self-assembly.

    PubMed

    Evans, Constantine G; Winfree, Erik

    2017-06-19

    DNA tiles provide a promising technique for assembling structures with nanoscale resolution through self-assembly by basic interactions rather than top-down assembly of individual structures. Tile systems can be programmed to grow based on logical rules, allowing for a small number of tile types to assemble large, complex assemblies that can retain nanoscale resolution. Such algorithmic systems can even assemble different structures using the same tiles, based on inputs that seed the growth. While programming and theoretical analysis of tile self-assembly often makes use of abstract logical models of growth, experimentally implemented systems are governed by nanoscale physical processes that can lead to very different behavior, more accurately modeled by taking into account the thermodynamics and kinetics of tile attachment and detachment in solution. This review discusses the relationships between more abstract and more physically realistic tile assembly models. A central concern is how consideration of model differences enables the design of tile systems that robustly exhibit the desired abstract behavior in realistic physical models and in experimental implementations. Conversely, we identify situations where self-assembly in abstract models can not be well-approximated by physically realistic models, putting constraints on physical relevance of the abstract models. To facilitate the discussion, we introduce a unified model of tile self-assembly that clarifies the relationships between several well-studied models in the literature. Throughout, we highlight open questions regarding the physical principles for DNA tile self-assembly.

  19. A Global User-Driven Model for Tile Prefetching in Web Geographical Information Systems.

    PubMed

    Pan, Shaoming; Chong, Yanwen; Zhang, Hang; Tan, Xicheng

    2017-01-01

    A web geographical information system is a typical service-intensive application. Tile prefetching and cache replacement can improve cache hit ratios by proactively fetching tiles from storage and replacing the appropriate tiles from the high-speed cache buffer without waiting for a client's requests, which reduces disk latency and improves system access performance. Most popular prefetching strategies consider only the relative tile popularities to predict which tile should be prefetched or consider only a single individual user's access behavior to determine which neighbor tiles need to be prefetched. Some studies show that comprehensively considering all users' access behaviors and all tiles' relationships in the prediction process can achieve more significant improvements. Thus, this work proposes a new global user-driven model for tile prefetching and cache replacement. First, based on all users' access behaviors, a type of expression method for tile correlation is designed and implemented. Then, a conditional prefetching probability can be computed based on the proposed correlation expression mode. Thus, some tiles to be prefetched can be found by computing and comparing the conditional prefetching probability from the uncached tiles set and, similarly, some replacement tiles can be found in the cache buffer according to multi-step prefetching. Finally, some experiments are provided comparing the proposed model with other global user-driven models, other single user-driven models, and other client-side prefetching strategies. The results show that the proposed model can achieve a prefetching hit rate in approximately 10.6% ~ 110.5% higher than the compared methods.

  20. Comparison of performance of tile drainage routines in SWAT 2009 and 2012 in an extensively tile-drained watershed in Midwest

    USDA-ARS?s Scientific Manuscript database

    Subsurface tile drainage systems are widely used in agricultural watersheds in the Midwestern U.S. Tile drainage systems enable the Midwest area to become highly productive agricultural lands, but can also create environmental problems, for example nitrate-N contamination associated with drainage w...

  1. Comparison of DNDC and RZWQM2 for simulating hydrology and nitrogen dynamics in a corn-soybean system with a winter cover crop

    NASA Astrophysics Data System (ADS)

    Desjardins, R.; Smith, W.; Qi, Z.; Grant, B.; VanderZaag, A.

    2017-12-01

    Biophysical models are needed for assessing science-based mitigation options to improve the efficiency and sustainability of agricultural cropping systems. In order to account for trade-offs between environmental indicators such as GHG emissions, soil C change, and water quality it is important that models can encapsulate the complex array of interrelated biogeochemical processes controlling water, nutrient and energy flows in the agroecosystem. The Denitrification Decomposition (DNDC) model is one of the most widely used process-based models, and is arguably the most sophisticated for estimating GHG emissions and soil C&N cycling, however, the model simulates only simple cascade water flow. The purpose of this study was to compare the performance of DNDC to a comprehensive water flow model, the Root Zone Water Quality Model (RZWQM2), to determine which processes in DNDC may be limiting and recommend improvements. Both models were calibrated and validated for simulating crop biomass, soil hydrology, and nitrogen loss to tile drains using detailed observations from a corn-soybean rotation in Iowa, with and without cover crops. Results indicated that crop yields, biomass and the annual estimation of nitrogen and water loss to tiles drains were well simulated by both models (NSE > 0.6 in all cases); however, RZWQM2 performed much better for simulating soil water content, and the dynamics of daily water flow (DNDC: NSE -0.32 to 0.28; RZWQM2: NSE 0.34 to 0.70) to tile drains. DNDC overestimated soil water content near the soil surface and underestimated it deeper in the profile which was presumably caused by the lack of a root distribution algorithm, the inability to simulate a heterogeneous profile and lack of a water table. We recommend these improvements along with the inclusion of enhanced water flow and a mechanistic tile drainage sub-model. The accurate temporal simulation of water and N strongly impacts several biogeochemical processes.

  2. Effect of load eccentricity and substructure deformation on ultimate strength of shuttle orbiter thermal protection system

    NASA Technical Reports Server (NTRS)

    Sawyer, J. W.

    1981-01-01

    The effect of load eccentricity and substructure deformation on the ultimate strength and stress displacement properties of the shuttle orbiter thermal protection system (TPS) was determined. The LI-900 Reusable Surface Insulation (RSI) tiles mounted on the .41 cm thick Strain Isolator Pad (SIP) were investigated. Substructure deformations reduce the ultimate strength of the SIP/tile TPS and increase the scatter in the ultimate strength data. Substructure deformations that occur unsymmetric to the tile can cause the tile to rotate when subjected to a uniform applied load. Load eccentricity reduces SIP/tile TPS ultimate strength and causes tile rotation.

  3. Revitalizing the Space Shuttle's Thermal Protection System with Reverse Engineering and 3D Vision Technology

    NASA Technical Reports Server (NTRS)

    Wilson, Brad; Galatzer, Yishai

    2008-01-01

    The Space Shuttle is protected by a Thermal Protection System (TPS) made of tens of thousands of individually shaped heat protection tile. With every flight, tiles are damaged on take-off and return to earth. After each mission, the heat tiles must be fixed or replaced depending on the level of damage. As part of the return to flight mission, the TPS requirements are more stringent, leading to a significant increase in heat tile replacements. The replacement operation requires scanning tile cavities, and in some cases the actual tiles. The 3D scan data is used to reverse engineer each tile into a precise CAD model, which in turn, is exported to a CAM system for the manufacture of the heat protection tile. Scanning is performed while other activities are going on in the shuttle processing facility. Many technicians work simultaneously on the space shuttle structure, which results in structural movements and vibrations. This paper will cover a portable, ultra-fast data acquisition approach used to scan surfaces in this unstable environment.

  4. Design, fabrication, and tests of a metallic shell tile thermal protection system for space transportation

    NASA Technical Reports Server (NTRS)

    Macconochie, Ian O.; Kelly, H. Neale

    1989-01-01

    A thermal protection tile for earth-to-orbit transports is described. The tiles consist of a rigid external shell filled with a flexible insulation. The tiles tend to be thicker than the current Shuttle rigidized silica tiles for the same entry heat load but are projected to be more durable and lighter. The tiles were thermally tested for several simulated entry trajectories.

  5. Structural tests on space shuttle thermal protection system constructed with nondensified and densified Li 900 and LI 2200 tile

    NASA Technical Reports Server (NTRS)

    Williams, J. G.

    1981-01-01

    Structural tests were conducted on thermal protection systems (TPS) LI 900 and LI 2200 tiles and .41 cm and .23 cm thick strain isolation pads. The bond surface of selected tiles was densified to obtain improved strength. Four basic types of experiments were conducted including tension tests, substrate mismatch (initial imperfection) tests, tension loads eccentrically applied, and pressure loads applied rapidly to the tile top surface. A small initial imperfection mismatch (2.29 m spherical radius on the substrate) did not influence significantly the ultimate failure strength. Densification of the tile bond region improved the strength of TPS constructed both of LI 900 tile and of LI 2200 tile. Pressure shock conditions studied did not significantly affect the TPS strength.

  6. A Global User-Driven Model for Tile Prefetching in Web Geographical Information Systems

    PubMed Central

    Pan, Shaoming; Chong, Yanwen; Zhang, Hang; Tan, Xicheng

    2017-01-01

    A web geographical information system is a typical service-intensive application. Tile prefetching and cache replacement can improve cache hit ratios by proactively fetching tiles from storage and replacing the appropriate tiles from the high-speed cache buffer without waiting for a client’s requests, which reduces disk latency and improves system access performance. Most popular prefetching strategies consider only the relative tile popularities to predict which tile should be prefetched or consider only a single individual user's access behavior to determine which neighbor tiles need to be prefetched. Some studies show that comprehensively considering all users’ access behaviors and all tiles’ relationships in the prediction process can achieve more significant improvements. Thus, this work proposes a new global user-driven model for tile prefetching and cache replacement. First, based on all users’ access behaviors, a type of expression method for tile correlation is designed and implemented. Then, a conditional prefetching probability can be computed based on the proposed correlation expression mode. Thus, some tiles to be prefetched can be found by computing and comparing the conditional prefetching probability from the uncached tiles set and, similarly, some replacement tiles can be found in the cache buffer according to multi-step prefetching. Finally, some experiments are provided comparing the proposed model with other global user-driven models, other single user-driven models, and other client-side prefetching strategies. The results show that the proposed model can achieve a prefetching hit rate in approximately 10.6% ~ 110.5% higher than the compared methods. PMID:28085937

  7. Mashup Scheme Design of Map Tiles Using Lightweight Open Source Webgis Platform

    NASA Astrophysics Data System (ADS)

    Hu, T.; Fan, J.; He, H.; Qin, L.; Li, G.

    2018-04-01

    To address the difficulty involved when using existing commercial Geographic Information System platforms to integrate multi-source image data fusion, this research proposes the loading of multi-source local tile data based on CesiumJS and examines the tile data organization mechanisms and spatial reference differences of the CesiumJS platform, as well as various tile data sources, such as Google maps, Map World, and Bing maps. Two types of tile data loading schemes have been designed for the mashup of tiles, the single data source loading scheme and the multi-data source loading scheme. The multi-sources of digital map tiles used in this paper cover two different but mainstream spatial references, the WGS84 coordinate system and the Web Mercator coordinate system. According to the experimental results, the single data source loading scheme and the multi-data source loading scheme with the same spatial coordinate system showed favorable visualization effects; however, the multi-data source loading scheme was prone to lead to tile image deformation when loading multi-source tile data with different spatial references. The resulting method provides a low cost and highly flexible solution for small and medium-scale GIS programs and has a certain potential for practical application values. The problem of deformation during the transition of different spatial references is an important topic for further research.

  8. Mechanical Face Seal Dynamics.

    DTIC Science & Technology

    1985-12-01

    1473, 83 APR EDITION OF I JAN 73 IS OBSOLETE. UNCLASSIFIED SECURITY CLASSIFICATION OF THIS PAGE -,1 - " P V 7 V - • ... f -N- PRE FACE This final...dimensionless mass m and support damping 1), ~ at-e aisas M"= -1,,i -4 4) y positive. ’he damping D is Ihe tinplete system of momeints acting on tile

  9. Power Transfer Efficiency of Mutually Coupled Coils in an Aluminum AUV Hull

    DTIC Science & Technology

    2013-12-01

    the tiles are made from a nickel -zinc material, a reasonable value is 20.0.r  38 Figure 24. Photograph of the ferrite board behind the...results were then compared to three sets of measured efficiency data: an IPT system without ferrite tiles; an IPT system with the receiving coil...attached to ferrite tiles; and an IPT system with the receiving coil/ ferrite tile combination placed inside an aluminum AUV hull. Efficiency was poor, less

  10. Substructure procedure for including tile flexibility in stress analysis of shuttle thermal protection system

    NASA Technical Reports Server (NTRS)

    Giles, G. L.

    1980-01-01

    A substructure procedure to include the flexibility of the tile in the stress analysis of the shuttle thermal protection system (TPS) is described. In this procedure, the TPS is divided into substructures of (1) the tile which is modeled by linear finite elements and (2) the SIP which is modeled as a nonlinear continuum. This procedure was applied for loading cases of uniform pressure, uniform moment, and an aerodynamic shock on various tile thicknesses. The ratios of through-the-thickness stresses in the SIP which were calculated using a flexible tile compared to using a rigid tile were found to be less than 1.05 for the cases considered.

  11. Filler bar heating due to stepped tiles in the shuttle orbiter thermal protection system

    NASA Technical Reports Server (NTRS)

    Petley, D. H.; Smith, D. M.; Edwards, C. L. W.; Patten, A. B.; Hamilton, H. H., II

    1983-01-01

    An analytical study was performed to investigate the excessive heating in the tile to tile gaps of the Shuttle Orbiter Thermal Protection System due to stepped tiles. The excessive heating was evidence by visible discoloration and charring of the filler bar and strain isolation pad that is used in the attachment of tiles to the aluminum substrate. Two tile locations on the Shuttle orbiter were considered, one on the lower surface of the fuselage and one on the lower surface of the wing. The gap heating analysis involved the calculation of external and internal gas pressures and temperatures, internal mass flow rates, and the transient thermal response of the thermal protection system. The results of the analysis are presented for the fuselage and wing location for several step heights. The results of a study to determine the effectiveness of a half height ceramic fiber gap filler in preventing hot gas flow in the tile gaps are also presented.

  12. Modal analysis and dynamic stresses for acoustically excited shuttle insulation tiles

    NASA Technical Reports Server (NTRS)

    Ojalvo, I. U.; Ogilvie, P. L.

    1975-01-01

    Improvements and extensions to the RESIST computer program developed for determining the normalized modal stress response of shuttle insulation tiles are described. The new version of RESIST can accommodate primary structure panels with closed-cell stringers, in addition to the capability for treating open-cell stringers. In addition, the present version of RESIST numerically solves vibration problems several times faster than its predecessor. A new digital computer program, titled ARREST (Acoustic Response of Reusable Shuttle Tiles) is also described. Starting with modal information contained on output tapes from RESIST computer runs, ARREST determines RMS stresses, deflections and accelerations of shuttle panels with reusable surface insulation tiles. Both programs are applicable to stringer stiffened structural panels with or without reusable surface insulation titles.

  13. Geometrical tile design for complex neighborhoods.

    PubMed

    Czeizler, Eugen; Kari, Lila

    2009-01-01

    Recent research has showed that tile systems are one of the most suitable theoretical frameworks for the spatial study and modeling of self-assembly processes, such as the formation of DNA and protein oligomeric structures. A Wang tile is a unit square, with glues on its edges, attaching to other tiles and forming larger and larger structures. Although quite intuitive, the idea of glues placed on the edges of a tile is not always natural for simulating the interactions occurring in some real systems. For example, when considering protein self-assembly, the shape of a protein is the main determinant of its functions and its interactions with other proteins. Our goal is to use geometric tiles, i.e., square tiles with geometrical protrusions on their edges, for simulating tiled paths (zippers) with complex neighborhoods, by ribbons of geometric tiles with simple, local neighborhoods. This paper is a step toward solving the general case of an arbitrary neighborhood, by proposing geometric tile designs that solve the case of a "tall" von Neumann neighborhood, the case of the f-shaped neighborhood, and the case of a 3 x 5 "filled" rectangular neighborhood. The techniques can be combined and generalized to solve the problem in the case of any neighborhood, centered at the tile of reference, and included in a 3 x (2k + 1) rectangle.

  14. Water table management reduces tile nitrate loss in continuous corn and in a soybean-corn rotation.

    PubMed

    Drury, C F; Tan, C S; Gaynor, J D; Reynolds, W D; Welacky, T W; Oloya, T O

    2001-10-25

    Water table management systems can be designed to alleviate soil water excesses and deficits, as well as reduce nitrate leaching losses in tile discharge. With this in mind, a standard tile drainage (DR) system was compared over 8 years (1991 to 1999) to a controlled tile drainage/subirrigation (CDS) system on a low-slope (0.05 to 0.1%) Brookston clay loam soil (Typic Argiaquoll) in southwestern Ontario, Canada. In the CDS system, tile discharge was controlled to prevent excessive drainage, and water was pumped back up the tile lines (subirrigation) to replenish the crop root zone during water deficit periods. In the first phase of the study (1991 to 1994), continuous corn (Zea mays, L.) was grown with annual nitrogen (N) fertilizer inputs as per local soil test recommendations. In the second phase (1995 to 1999), a soybean (Glycine max L., Merr.)-corn rotation was used with N fertilizer added only during the two corn years. In Phase 1 when continuous corn was grown, CDS reduced total tile discharge by 26% and total nitrate loss in tile discharge by 55%, compared to DR. In addition, the 4-year flow weighted mean (FWM) nitrate concentration in tile discharge exceeded the Canadian drinking water guideline (10 mg N l(-1)) under DR (11.4 mg N l(-1)), but not under CDS (7.0 mg N l(-1)). In Phase 2 during the soybean-corn rotation, CDS reduced total tile discharge by 38% and total nitrate loss in tile discharge by 66%, relative to DR. The 4-year FWM nitrate concentration during Phase 2 in tile discharge was below the drinking water guideline for both DR (7.3 mg N l(-1)) and CDS (4.0 mg N l(-1)). During both phases of the experiment, the CDS treatment caused only minor increases in nitrate loss in surface runoff relative to DR. Hence CDS decreased FWM nitrate concentrations, total drainage water loss, and total nitrate loss in tile discharge relative to DR. In addition, soybean-corn rotation reduced FWM nitrate concentrations and total nitrate loss in tile discharge relative to continuous corn. CDS and crop rotations with reduced N fertilizer inputs can thus improve the quality of tile discharge water substantially.

  15. Experimental Design for the Evaluation of Detection Techniques of Hidden Corrosion Beneath the Thermal Protective System of the Space Shuttle Orbiter

    NASA Technical Reports Server (NTRS)

    Kemmerer, Catherine C.; Jacoby, Joseph A.; Lomness, Janice K.; Hintze, Paul E.; Russell, Richard W.

    2007-01-01

    The detection of corrosion beneath Space Shuttle Orbiter thermal protective system is traditionally accomplished by removing the Reusable Surface Insulation tiles and performing a visual inspection of the aluminum substrate and corrosion protection system. This process is time consuming and has the potential to damage high cost tiles. To evaluate non-intrusive NDE methods, a Proof of Concept (PoC) experiment was designed and test panels were manufactured. The objective of the test plan was three-fold: establish the ability to detect corrosion hidden from view by tiles; determine the key factor affecting detectability; roughly quantify the detection threshold. The plan consisted of artificially inducing dimensionally controlled corrosion spots in two panels and rebonding tile over the spots to model the thermal protective system of the orbiter. The corrosion spot diameter ranged from 0.100" to 0.600" inches and the depth ranged from 0.003" to 0.020". One panel consisted of a complete factorial array of corrosion spots with and without tile coverage. The second panel consisted of randomized factorial points replicated and hidden by tile. Conventional methods such as ultrasonics, infrared, eddy current and microwave methods have shortcomings. Ultrasonics and IR cannot sufficiently penetrate the tiles, while eddy current and microwaves have inadequate resolution. As such, the panels were interrogated using Backscatter Radiography and Terahertz Imaging. The terahertz system successfully detected artificially induced corrosion spots under orbiter tile and functional testing is in-work in preparation for implementation.

  16. Introducing new technologies into Space Station subsystems

    NASA Technical Reports Server (NTRS)

    Wiskerchen, Michael J.; Mollakarimi, Cindy L.

    1989-01-01

    A new systems engineering technology has been developed and applied to Shuttle processing. The new engineering approach emphasizes the identification, quantitative assessment, and management of system performance and risk related to the dynamic nature of requirements, technology, and operational concepts. The Space Shuttle Tile Automation System is described as an example of the first application of the new engineering technology. Lessons learned from the Shuttle processing experience are examined, and concepts are presented which are applicable to the design and development of the Space Station Freedom.

  17. An Analysis of the Selected Materials Used in Step Measurements During Pre-Fits of Thermal Protection System Tiles and the Accuracy of Measurements Made Using These Selected Materials

    NASA Technical Reports Server (NTRS)

    Kranz, David William

    2010-01-01

    The goal of this research project was be to compare and contrast the selected materials used in step measurements during pre-fits of thermal protection system tiles and to compare and contrast the accuracy of measurements made using these selected materials. The reasoning for conducting this test was to obtain a clearer understanding to which of these materials may yield the highest accuracy rate of exacting measurements in comparison to the completed tile bond. These results in turn will be presented to United Space Alliance and Boeing North America for their own analysis and determination. Aerospace structures operate under extreme thermal environments. Hot external aerothermal environments in high Mach number flights lead to high structural temperatures. The differences between tile heights from one to another are very critical during these high Mach reentries. The Space Shuttle Thermal Protection System is a very delicate and highly calculated system. The thermal tiles on the ship are measured to within an accuracy of .001 of an inch. The accuracy of these tile measurements is critical to a successful reentry of an orbiter. This is why it is necessary to find the most accurate method for measuring the height of each tile in comparison to each of the other tiles. The test results indicated that there were indeed differences in the selected materials used in step measurements during prefits of Thermal Protection System Tiles and that Bees' Wax yielded a higher rate of accuracy when compared to the baseline test. In addition, testing for experience level in accuracy yielded no evidence of difference to be found. Lastly the use of the Trammel tool over the Shim Pack yielded variable difference for those tests.

  18. Geometrical Tile Design for Complex Neighborhoods

    PubMed Central

    Czeizler, Eugen; Kari, Lila

    2009-01-01

    Recent research has showed that tile systems are one of the most suitable theoretical frameworks for the spatial study and modeling of self-assembly processes, such as the formation of DNA and protein oligomeric structures. A Wang tile is a unit square, with glues on its edges, attaching to other tiles and forming larger and larger structures. Although quite intuitive, the idea of glues placed on the edges of a tile is not always natural for simulating the interactions occurring in some real systems. For example, when considering protein self-assembly, the shape of a protein is the main determinant of its functions and its interactions with other proteins. Our goal is to use geometric tiles, i.e., square tiles with geometrical protrusions on their edges, for simulating tiled paths (zippers) with complex neighborhoods, by ribbons of geometric tiles with simple, local neighborhoods. This paper is a step toward solving the general case of an arbitrary neighborhood, by proposing geometric tile designs that solve the case of a “tall” von Neumann neighborhood, the case of the f-shaped neighborhood, and the case of a 3 × 5 “filled” rectangular neighborhood. The techniques can be combined and generalized to solve the problem in the case of any neighborhood, centered at the tile of reference, and included in a 3 × (2k + 1) rectangle. PMID:19956398

  19. KSC-06pd0022

    NASA Image and Video Library

    2006-01-11

    KENNEDY SPACE CENTER, FLA. - In the Thermal Protection System Facility, Tim Wright, engineering manager with United Space Alliance, tests a new tile, called "Boeing replacement insulation" or "BRI-18." The new tiles will gradually replace older tiles around main landing gear doors, external tank doors and nose landing gear doors. Currently, 10 tiles have been processed inside the facility. Discovery will receive the first BRI-18 tiles. Technicians inside the Orbiter Processing Facility are performing fit checks and will begin bonding the tiles to the vehicle this month. The raw material is manufactured by The Boeing Company in Huntington Beach, Calif. Replacing older tile with the BRI-18 tile in strategic areas is one of the Columbia Accident Investigation Board's recommendations to strengthen the orbiters. The tiles are more impact resistant than previous designs, enhancing the crew’s safety.

  20. KSC-06pd0021

    NASA Image and Video Library

    2006-01-11

    KENNEDY SPACE CENTER, FLA. - In the Thermal Protection System Facility, Tim Wright, engineering manager with United Space Alliance, tests a new tile, called "Boeing replacement insulation" or "BRI-18." The new tiles will gradually replace older tiles around main landing gear doors, external tank doors and nose landing gear doors. Currently, 10 tiles have been processed inside the facility. Discovery will receive the first BRI-18 tiles. Technicians inside the Orbiter Processing Facility are performing fit checks and will begin bonding the tiles to the vehicle this month. The raw material is manufactured by The Boeing Company in Huntington Beach, Calif. Replacing older tile with the BRI-18 tile in strategic areas is one of the Columbia Accident Investigation Board's recommendations to strengthen the orbiters. The tiles are more impact resistant than previous designs, enhancing the crew’s safety.

  1. Shell tile thermal protection system

    NASA Technical Reports Server (NTRS)

    Macconochie, I. O.; Lawson, A. G.; Kelly, H. N. (Inventor)

    1984-01-01

    A reusable, externally applied thermal protection system for use on aerospace vehicles subject to high thermal and mechanical stresses utilizes a shell tile structure which effectively separates its primary functions as an insulator and load absorber. The tile consists of structurally strong upper and lower metallic shells manufactured from materials meeting the thermal and structural requirements incident to tile placement on the spacecraft. A lightweight, high temperature package of insulation is utilized in the upper shell while a lightweight, low temperature insulation is utilized in the lower shell. Assembly of the tile which is facilitated by a self-locking mechanism, may occur subsequent to installation of the lower shell on the spacecraft structural skin.

  2. Evaluation of the hooghoudt and kirkham tile drain equations in the soil and water assessment tool to simulate tile flow and nitrate-nitrogen.

    PubMed

    Moriasi, Daniel N; Gowda, Prasanna H; Arnold, Jeffrey G; Mulla, David J; Ale, Srinivasulu; Steiner, Jean L; Tomer, Mark D

    2013-11-01

    Subsurface tile drains in agricultural systems of the midwestern United States are a major contributor of nitrate-N (NO-N) loadings to hypoxic conditions in the Gulf of Mexico. Hydrologic and water quality models, such as the Soil and Water Assessment Tool, are widely used to simulate tile drainage systems. The Hooghoudt and Kirkham tile drain equations in the Soil and Water Assessment Tool have not been rigorously tested for predicting tile flow and the corresponding NO-N losses. In this study, long-term (1983-1996) monitoring plot data from southern Minnesota were used to evaluate the SWAT version 2009 revision 531 (hereafter referred to as SWAT) model for accurately estimating subsurface tile drain flows and associated NO-N losses. A retention parameter adjustment factor was incorporated to account for the effects of tile drainage and slope changes on the computation of surface runoff using the curve number method (hereafter referred to as Revised SWAT). The SWAT and Revised SWAT models were calibrated and validated for tile flow and associated NO-N losses. Results indicated that, on average, Revised SWAT predicted monthly tile flow and associated NO-N losses better than SWAT by 48 and 28%, respectively. For the calibration period, the Revised SWAT model simulated tile flow and NO-N losses within 4 and 1% of the observed data, respectively. For the validation period, it simulated tile flow and NO-N losses within 8 and 2%, respectively, of the observed values. Therefore, the Revised SWAT model is expected to provide more accurate simulation of the effectiveness of tile drainage and NO-N management practices. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  3. Elevated waterproof access floor system and method of making the same

    NASA Technical Reports Server (NTRS)

    Cohen, Marc M. (Inventor)

    1987-01-01

    An elevated waterproof access floor system having subfloor channels or compartments for power lines, gas lines or the like is adapted such that it can be opened and subsequently resealed without destroying the waterproofing and without destroying its aesthetic appearance. A multiplicity of tiles are supported on a support grid, and a flooring sheet is supported on the tiles. Attachment means are provided to prevent lateral but not vertical movement of the flooring sheet with respect to the tiles so that the flooring sheet can be lifted off the tiles, but when the flooring sheet is supported on the tiles, no lateral slipping will occur. The flooring sheet is made of a heat resealable material, so that it can be cut away in sections, and the tiles therebelow lifted off, to provide access to subfloor compartments.

  4. Thermal and aerothermal performance of a titanium multiwall thermal protection system

    NASA Technical Reports Server (NTRS)

    Avery, D. E.; Shideler, J. L.; Stuckey, R. N.

    1981-01-01

    A metallic thermal protection system (TPS) concept the multiwall designed for temperature and pressure at Shuttle body point 3140 where the maximum surface temperature is approximately 811 K was tested to evaluate thermal performance and structural integrity. A two tile model of titanium multiwall and a model consisting of a low temperature reusable surface insulation (LRSI) tiles were exposed to 25 simulated thermal and pressure Shuttle entry missions. The two systems performed the same, and neither system deteriorated during the tests. It is indicated that redesign of the multiwall tiles reduces tile thickness and/or weight. A nine tile model of titanium multiwal was tested for radiant heating and aerothermodynamics. Minor design changes that improve structural integrity without having a significant impact on the thermal protection ability of the titanium multiwall TPS are identified. The capability of a titanium multiwall thermal protection system to protect an aluminum surface during a Shuttle type entry trajectory at locations on the vehicle where the maximum surface temperature is below 811 K is demonstrated.

  5. Tile-based Level of Detail for the Parallel Age

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Niski, K; Cohen, J D

    Today's PCs incorporate multiple CPUs and GPUs and are easily arranged in clusters for high-performance, interactive graphics. We present an approach based on hierarchical, screen-space tiles to parallelizing rendering with level of detail. Adapt tiles, render tiles, and machine tiles are associated with CPUs, GPUs, and PCs, respectively, to efficiently parallelize the workload with good resource utilization. Adaptive tile sizes provide load balancing while our level of detail system allows total and independent management of the load on CPUs and GPUs. We demonstrate our approach on parallel configurations consisting of both single PCs and a cluster of PCs.

  6. An experimental summary of plasma arc exposures of space shuttle high-temperature reusable surface insulation tile array with a single missing tile (conducted at the Ames Research Center)

    NASA Technical Reports Server (NTRS)

    Galanter, S. A.

    1975-01-01

    A space shuttle high temperature reusable surface insulation (HRSI) tile array with a single missing or lost tile was exposed to a hot gas simulated reentry environment to investigate the heating conditions in and around the vicinity of the missing HRSI tile. Heat flux and pressure data for the lost tile condition were obtained by the use of a water cooled lost tile calibration model. The maximum aluminum substrate temperature obtained during the simulated reentry was 128 C (263 F). The lost tile calibration data indicated a maximum heat flux in the lost tile cavity region of 63 percent of the upstream reference value. This test was conducted at the Ames Research Center in the 20 MW semielliptical thermal protection system (TPS) pilot plasma arc test facility.

  7. Structure of the Jovian Magnetodisk Current Sheet: Initial Galileo Observations

    NASA Technical Reports Server (NTRS)

    Russell, C. T.; Huddleston, D. E.; Khurana, K. K.; Kivelson, M. G.

    2001-01-01

    The ten-degree tilt of the Jovian magnetic dipole causes the magnetic equator to move back and forth across Jupiter's rotational equator and tile Galileo orbit that lies therein. Beyond about 24 Jovian radii, the equatorial current sheet thins and tile magnetic structure changes from quasi-dipolar into magnetodisk-like with two regions of nearly radial but antiparallel magnetic field separated by a strong current layer. The magnetic field at the center of the current sheet is very weak in this region. Herein we examine tile current sheet at radial distances from 24 55 Jovian radii. We find that the magnetic structure very much resembles tile structure seen at planetary magnetopause and tail current sheet crossings. Tile magnetic field variation is mainly linear with little rotation of the field direction, At times there is almost no small-scale structure present and the normal component of the magnetic field is almost constant through the current sheet. At other times there are strong small-scale structures present in both the southward and northward directions. This small-scale structure appears to grow with radial distance and may provide the seeds for tile explosive reconnection observed at even greater radial distances oil tile nightside. Beyond about 40 Jovian radii, the thin current sheet also appears to be almost constantly in oscillatory motion with periods of about 10 min. The amplitude of these oscillations also appears to grow with radial distance. The source of these fluctuations may be dynamical events in tile more distant magnetodisk.

  8. Fracture behavior of the Space Shuttle thermal protection system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Komine, A.; Kobayashi, A.S.

    1983-09-01

    Stable crack-growth and fracture-toughness experiments were conducted using precracked specimens machined from LI-900 reusable surface insulation (RSI) tiles of the Space Shuttle thermal protection system (TPS) at room temperature. Similar fracture experiments were conducted on fracture specimens with preexisting cracks at the interface of the tile and the strain isolation pad (SIP). Stable crack growth was not observed in the LI-900 tile fracture specimens which had a fracture toughness of 12.0 kPa sq rt of m. The intermittent subcritical crack growth at the tile-pad interface of the fracture specimens was attributed to successive local pull-outs due to tensile overload inmore » the LI-900 tile and cannot be characterized by linear elastic fracture mechanics. No subcritical interfacial crack growth was observed in the fracture specimens with densified LI-900 tiles where brittle fracture initiated at an interior point away from the densification. 11 references.« less

  9. Photovoltaic roofing tile systems

    NASA Astrophysics Data System (ADS)

    Melchior, B.

    The integration of photovoltaic (PV) systems in architecture is discussed. A PV-solar roofing tile system with polymer concrete base; PV-roofing tile with elastomer frame profiles and aluminum profile frames; contact technique; and solar cell modules measuring technique are described. Field tests at several places were conducted on the solar generator, electric current behavior, battery station, electric installation, power conditioner, solar measuring system with magnetic bubble memory technique, data transmission via telephone modems, and data processing system. The very favorable response to the PV-compact system proves the commercial possibilities of photovoltaic integration in architecture.

  10. Producing the high temperature reusable surface insulation for the thermal protection system of the Space Shuttle

    NASA Technical Reports Server (NTRS)

    Forgsberg, K.

    1979-01-01

    The primary insulation system used to protect the space shuttle orbiter on reentry is an externally attached, rigidized, fibrous silica which has been machined into tiles. The tiles constitute the temperature reusable surface insulation system and are used on over 70 percent of the vehicle exterior surface where peak temperatures range from 400 to 1260 C. Cargon-carbon leading edges are used in areas where peak temperatures exceed 1650 C and a felt flexible insulation is used in regions below 400 C. Approximately 32,000 tiles are used in the HRST system and because of vehicle configuration, aerodynamic requirements, and weight considerations no two tiles are alike. Fabrication and quality control procedures are described.

  11. Characterization of particulate and dissolved phosphorus in tile and nearby riverine systems

    NASA Astrophysics Data System (ADS)

    Jiang, X.; Arai, Y.; David, M.; Gentry, L.

    2017-12-01

    In the Midwestern U.S., the drainage of agricultural land is predominantly managed by the tile drain system because of its poorly drain properties of clay rich indigenous soils. An accelerated subsurface flow of phosphorus (P) has recently been documented as a primary P transport path in contrast to the typical surface runoff events observed in the Eastern U.S. Recent studies suggested the important role of particulate P (PP) load in agricultural tile drainage water during high flow events. It was hypothesized that PP in the tile water is transported to riverine system contributing to the negative environmental impacts in the Midwestern U.S. In this study, correlation assessment of physicochemical properties of PP in agricultural tile drainage and nearby river samples after a storm event was conducted using a combination of 31P-nuclear magnetic resonance spectroscopy, P K-edge X-ray absorption near edge structure spectroscopy, X-ray diffraction, zetasizer, and transmission electron microscopy. Results show that significantly more colloidal (i.e. 1 nm- 2 µm) and silt-sized (i.e. > 2 µm) particles as well as higher dissolved total P (DTP) and dissolved reactive P (DRP) concentrations existed in river samples than tile samples. Tile and river samples showed similar zeta potential in each particle-size fraction and similar element distributions on colloidal fraction. However, colloidal P concentration and distribution are slightly different between tile and river samples: more colloidal total P and organic P existed in tile colloids than river colloids. The results of P speciation and mineralogical assessment will also be discussed.

  12. Development of a nondestructive vibration technique for bond assessment of Space Shuttle tiles

    NASA Technical Reports Server (NTRS)

    Moslehy, Faissal A.

    1994-01-01

    This final report describes the achievements of the above titled project. The project is funded by NASA-KSC (Grant No. NAG 10-0117) for the period of 1 Jan. to 31 Dec. 1993. The purpose of this project was to develop a nondestructive, noncontact technique based on 'vibration signature' of tile systems to quantify the bond conditions of the thermal protection system) tiles of Space Shuttle orbiters. The technique uses a laser rapid scan system, modal measurements, and finite element modeling. Finite element models were developed for tiles bonded to both clamped and deformable integrated skin-stringer orbiter mid-fuselage. Results showed that the size and location of a disbonded tile can be determined from frequency and mode shape information. Moreover, a frequency response survey was used to quickly identify the disbonded tiles. The finite element results were compared with experimentally determined frequency responses of a 17-tile test panel, where a rapidscan laser system was employed. An excellent degree of correlation between the mathematical simulation and experimental results was realized. An inverse solution for single-tile assemblies was also derived and is being implemented into a computer program that can interact with the modal testing software. The output of the program displays the size and location of disbond. This program has been tested with simulated input (i.e., finite element data), and excellent agreement between predicted and simulated disbonds was shown. Finally, laser vibration imaging and acoustic emission techniques were shown to be well suited for detecting and monitoring the progressive damage in Graphite/Epoxy composite materials.

  13. TileDCS web system

    NASA Astrophysics Data System (ADS)

    Maidantchik, C.; Ferreira, F.; Grael, F.; Atlas Tile Calorimeter Community

    2010-04-01

    The web system described here provides features to monitor the ATLAS Detector Control System (DCS) acquired data. The DCS is responsible for overseeing the coherent and safe operation of the ATLAS experiment hardware. In the context of the Hadronic Tile Calorimeter Detector (TileCal), it controls the power supplies of the readout electronics acquiring voltages, currents, temperatures and coolant pressure measurements. The physics data taking requires the stable operation of the power sources. The TileDCS Web System retrieves automatically data and extracts the statistics for given periods of time. The mean and standard deviation outcomes are stored as XML files and are compared to preset thresholds. Further, a graphical representation of the TileCal cylinders indicates the state of the supply system of each detector drawer. Colors are designated for each kind of state. In this way problems are easier to find and the collaboration members can focus on them. The user selects a module and the system presents detailed information. It is possible to verify the statistics and generate charts of the parameters over the time. The TileDCS Web System also presents information about the power supplies latest status. One wedge is colored green whenever the system is on. Otherwise it is colored red. Furthermore, it is possible to perform customized analysis. It provides search interfaces where the user can set the module, parameters, and the time period of interest. The system also produces the output of the retrieved data as charts, XML files, CSV and ROOT files according to the user's choice.

  14. Steep-Slope Assembly Testing of Clay and Concrete Tile With and Without Cool Pigmented Colors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Miller, William A

    Cool color pigments and sub-tile venting of clay and concrete tile roofs significantly impact the heat flow crossing the roof deck of a steep-slope roof. Field measures for the tile roofs revealed a 70% drop in the peak heat flow crossing the deck as compared to a direct-nailed asphalt shingle roof. The Tile Roofing Institute (TRI) and its affiliate members are keenly interested in documenting the magnitude of the drop for obtaining solar reflectance credits with state and federal "cool roof" building efficiency standards. Tile roofs are direct-nailed or are attached to a deck with batten or batten and counter-battenmore » construction. S-Misson clay and concrete tile roofs, a medium-profile concrete tile roof, and a flat slate tile roof were installed on fully nstrumented attic test assemblies. Temperature measures of the roof, deck, attic, and ceiling, heat flows, solar reflectance, thermal emittance, and the ambient weather were recorded for each of the tile roofs and also on an adjacent attic cavity covered with a conventional pigmented and directnailed asphalt shingle roof. ORNL measured the tile's underside temperature and the bulk air temperature and heat flows just underneath the tile for batten and counter-batten tile systems and compared the results to the conventional asphalt shingle.« less

  15. A design rationale for NASA TileWorld

    NASA Technical Reports Server (NTRS)

    Philips, Andrew B.; Swanson, Keith J.; Drummond, Mark E.; Bresina, John L.

    1991-01-01

    Automated systems that can operate in unrestricted real-world domains are still well beyond current computational capabilities. This paper argues that isolating essential problem characteristics found in real-world domains allows for a careful study of how particular control systems operate. By isolating essential problem characteristics and studying their impact on autonomous system performance, we should be able to more quickly deliver systems for practical real-world problems. For our research on planning, scheduling, and control, we have selected three particular domain attributes to study: exogenous events, uncertain action outcome, and metric time. We are not suggesting that studies of these attributes in isolation are sufficient to guarantee the obvious goals of good methodology, brilliant architectures, or first-class results; however, we are suggesting that such isolation facilitates the achievement of these goals. To study these attributes, we have developed the NASA TileWorld. We describe the NASA TileWorld simulator in general terms, present an example NASA TileWorld problem, and discuss some of our motivations and concerns for NASA TileWorld.

  16. Advanced leading edge thermal-structure concept. Direct bond reusable surface insulation to a composite structure

    NASA Technical Reports Server (NTRS)

    Riccitiello, S. R.; Figueroa, H.; Coe, C. F.; Kuo, C. P.

    1984-01-01

    An advanced leading-edge concept was analyzed using the space shuttle leading edge system as a reference model. The comparison indicates that a direct-bond system utilizing a high temperature (2700 F) fibrous refractory composite insulation tile bonded to a high temperature (PI/graphite) composite structure can result in a weight savings of up to 800 lb. The concern that tile damage or loss during ascent would result in adverse entry aerodynamics if a leading edge tile system were used is addressed. It was found from experiment that missing tiles (as many as 22) on the leading edge would not significantly affect the basic force-and-moment aerodynamic coefficients. Additionally, this concept affords a degree of redundancy to a thermal protection system in that the base structure (being a composite material) ablates and neither melts nor burns through when subjected to entry heating in the event tiles are actually lost or damaged during ascent.

  17. Thermal insulation attaching means. [adhesive bonding of felt vibration insulators under ceramic tiles

    NASA Technical Reports Server (NTRS)

    Leger, L. J. (Inventor)

    1978-01-01

    An improved isolation system is provided for attaching ceramic tiles of insulating material to the surface of a structure to be protected against extreme temperatures of the nature expected to be encountered by the space shuttle orbiter. This system isolates the fragile ceramic tiles from thermally and mechanically induced vehicle structural strains. The insulating tiles are affixed to a felt isolation pad formed of closely arranged and randomly oriented fibers by means of a flexible adhesive and in turn the felt pad is affixed to the metallic vehicle structure by an additional layer of flexible adhesive.

  18. Beyond Aztec Castles: Toric Cascades in the dP 3 Quiver

    NASA Astrophysics Data System (ADS)

    Lai, Tri; Musiker, Gregg

    2017-12-01

    Given one of an infinite class of supersymmetric quiver gauge theories, string theorists can associate a corresponding toric variety (which is a Calabi-Yau 3-fold) as well as an associated combinatorial model known as a brane tiling. In combinatorial language, a brane tiling is a bipartite graph on a torus and its perfect matchings are of interest to both combinatorialists and physicists alike. A cluster algebra may also be associated to such quivers and in this paper we study the generators of this algebra, known as cluster variables, for the quiver associated to the cone over the del Pezzo surface d P 3. In particular, mutation sequences involving mutations exclusively at vertices with two in-coming arrows and two out-going arrows are referred to as toric cascades in the string theory literature. Such toric cascades give rise to interesting discrete integrable systems on the level of cluster variable dynamics. We provide an explicit algebraic formula for all cluster variables that are reachable by toric cascades as well as a combinatorial interpretation involving perfect matchings of subgraphs of the d P 3 brane tiling for these formulas in most cases.

  19. Isotopic mixing model for quantifying contributions of soil water and groundwater in subsurface ('tile') drainage

    NASA Astrophysics Data System (ADS)

    Kennedy, C. D.; Gall, H.; Jafvert, C. T.; Bowen, G. J.

    2010-12-01

    Subsurface (‘tile’) drainage, consisting of buried grids of perforated pipe, has provided a means of converting millions of acres of poorly drained soils in the Midwestern U.S. into fertile cropland. However, by altering pathways and rates of soil water and groundwater movement through agricultural lands, this practice may accelerate the loss of nitrate and other agrochemicals. To better understand the hydrological controls on nitrogen dynamics in artificially drained agricultural watersheds, a field sampling program has been established at the Animal Science Research and Education Center (ASREC) at Purdue University (West Lafayette, Indiana) to (1) measure precipitation amount, tile flow, and water-table elevation, and (2) collect water samples for analysis of nitrate, major ions, and oxygen isotope ratios in precipitation, tile drainage, shallow (1 m) and deep (3 m) groundwater, and soil water during storm events. Preliminary physical, chemical, and isotopic data collected at the ASREC show a coincident timing of peak storm ‘event water’ and peak nitrate flux in tile drainage, suggesting significant routing of infiltrating event water. In this work, we aim to refine our understanding of tile drainage at the ASREC by developing a mixing model for partitioning contributions of soil water and groundwater in tile drainage during several storm runoff events ranging in precipitation intensity and coinciding with varying antecedent soil moisture conditions. The results of our model will describe tile drainage in terms of its hydrological components, soil water and groundwater, which in turn will provide a means of incorporating the effects of tile drainage in surface/subsurface hydrological transport models.

  20. A portable high-power diode laser-based single-stage ceramic tile grout sealing system

    NASA Astrophysics Data System (ADS)

    Lawrence, J.; Schmidt, M. J. J.; Li, L.; Edwards, R. E.; Gale, A. W.

    2002-02-01

    By means of a 60 W high-power diode laser (HPDL) and a specially developed grout material the void between adjoining ceramic tiles has been successfully sealed. A single-stage process has been developed which uses a crushed ceramic tile mix to act as a tough, inexpensive bulk substrate and a glazed enamel surface to provide an impervious surface glaze. The single-stage ceramic tile grout sealing process yielded seals produced in normal atmospheric conditions that displayed no discernible cracks and porosities. The single-stage grout is simple to formulate and easy to apply. Tiles were successfully sealed with power densities as low as 200 kW/ mm2 and at rates of up to 600 mm/ min. Bonding of the enamel to the crushed ceramic tile mix was identified as being primarily due to van der Waals forces and, on a very small scale, some of the crushed ceramic tile mix material dissolving into the glaze. In terms of mechanical, physical and chemical characteristics, the single-stage ceramic tile grout was found to be far superior to the conventional epoxy tile grout and, in many instances, matched and occasionally surpassed that of the ceramic tiles themselves. What is more, the development of a hand-held HPDL beam delivery unit and the related procedures necessary to lead to the commercialisation of the single-stage ceramic tile grout sealing process are presented. Further, an appraisal of the potential hazards associated with the use of the HPDL in an industrial environment and the solutions implemented to ensure that the system complies with the relevant safety standards are given.

  1. Tile drainage phosphorus loss with long-term consistent cropping systems and fertilization.

    PubMed

    Zhang, T Q; Tan, C S; Zheng, Z M; Drury, C F

    2015-03-01

    Phosphorus (P) loss in tile drainage water may vary with agricultural practices, and the impacts are often hard to detect with short-term studies. We evaluated the effects of long-term (≥43 yr) cropping systems (continuous corn [CC], corn-oats-alfalfa-alfalfa rotation [CR], and continuous grass [CS]) and fertilization (fertilization [F] vs. no-fertilization [NF]) on P loss in tile drainage water from a clay loam soil over a 4-yr period. Compared with NF, long-term fertilization increased concentrations and losses of dissolved reactive P (DRP), dissolved unreactive P (DURP), and total P (TP) in tile drainage water, with the increments following the order: CS > CR > CC. Dissolved P (dissolved reactive P [DRP] and dissolved unreactive P [DURP]) was the dominant P form in drainage outflow, accounting for 72% of TP loss under F-CS, whereas particulate P (PP) was the major form of TP loss under F-CC (72%), F-CR (62%), NF-CS (66%), NF-CC (74%), and NF-CR (72%). Dissolved unreactive P played nearly equal roles as DRP in P losses in tile drainage water. Stepwise regression analysis showed that the concentration of P (DRP, DURP, and PP) in tile drainage flow, rather than event flow volume, was the most important factor contributing to P loss in tile drainage water, although event flow volume was more important in PP loss than in dissolved P loss. Continuous grass significantly increased P loss by increasing P concentration and flow volume of tile drainage water, especially under the fertilization treatment. Long-term grasslands may become a significant P source in tile-drained systems when they receive regular P addition. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  2. Fractal spectral triples on Kellendonk's C∗-algebra of a substitution tiling

    NASA Astrophysics Data System (ADS)

    Mampusti, Michael; Whittaker, Michael F.

    2017-02-01

    We introduce a new class of noncommutative spectral triples on Kellendonk's C∗-algebra associated with a nonperiodic substitution tiling. These spectral triples are constructed from fractal trees on tilings, which define a geodesic distance between any two tiles in the tiling. Since fractals typically have infinite Euclidean length, the geodesic distance is defined using Perron-Frobenius theory, and is self-similar with scaling factor given by the Perron-Frobenius eigenvalue. We show that each spectral triple is θ-summable, and respects the hierarchy of the substitution system. To elucidate our results, we construct a fractal tree on the Penrose tiling, and explicitly show how it gives rise to a collection of spectral triples.

  3. KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, KSC employee Chris Moore repairs tile on the forward area of the orbiter Discovery. The vehicle has undergone Orbiter Major Modifications in the past year, which includes tile check and repair. The tiles are part of the Orbiter Thermal Protection System, thermal shields to protect against temperatures as high as 3,000° Fahrenheit, which are produced during descent for landing. Discovery is scheduled to fly on mission STS-121 to the International Space Station.

    NASA Image and Video Library

    2003-12-09

    KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, KSC employee Chris Moore repairs tile on the forward area of the orbiter Discovery. The vehicle has undergone Orbiter Major Modifications in the past year, which includes tile check and repair. The tiles are part of the Orbiter Thermal Protection System, thermal shields to protect against temperatures as high as 3,000° Fahrenheit, which are produced during descent for landing. Discovery is scheduled to fly on mission STS-121 to the International Space Station.

  4. Robotic system for the servicing of the orbiter thermal protection system

    NASA Technical Reports Server (NTRS)

    Graham, Todd; Bennett, Richard; Dowling, Kevin; Manouchehri, Davoud; Cooper, Eric; Cowan, Cregg

    1994-01-01

    This paper describes the design and development of a mobile robotic system to process orbiter thermal protection system (TPS) tiles. This work was justified by a TPS automation study which identified tile rewaterproofing and visual inspection as excellent applications for robotic automation.

  5. Use of an engineering data management system in the analysis of Space Shuttle Orbiter tiles

    NASA Technical Reports Server (NTRS)

    Giles, G. L.; Vallas, M.

    1981-01-01

    This paper demonstrates the use of an engineering data management system to facilitate the extensive stress analyses of the Space Shuttle Orbiter thermal protection system. Descriptions are given of the approach and methods used (1) to gather, organize, and store the data, (2) to query data interactively, (3) to generate graphic displays of the data, and (4) to access, transform, and prepare the data for input to a stress analysis program. The relational information management system was found to be well suited to the tile analysis problem because information related to many separate tiles could be accessed individually from a data base having a natural organization from an engineering viewpoint. The flexible user features of the system facilitated changes in data content and organization which occurred during the development and refinement of the tile analysis procedure. Additionally, the query language supported retrieval of data to satisfy a variety of user-specified conditions.

  6. ATLAS Tile calorimeter calibration and monitoring systems

    NASA Astrophysics Data System (ADS)

    Chomont, Arthur; ATLAS Collaboration

    2017-11-01

    The ATLAS Tile Calorimeter (TileCal) is the central section of the hadronic calorimeter of the ATLAS experiment and provides important information for reconstruction of hadrons, jets, hadronic decays of tau leptons and missing transverse energy. This sampling calorimeter uses steel plates as absorber and scintillating tiles as active medium. The light produced by the passage of charged particles is transmitted by wavelength shifting fibres to photomultiplier tubes (PMTs), located on the outside of the calorimeter. The readout is segmented into about 5000 cells (longitudinally and transversally), each of them being read out by two PMTs in parallel. To calibrate and monitor the stability and performance of each part of the readout chain during the data taking, a set of calibration systems is used. The TileCal calibration system comprises cesium radioactive sources, Laser and charge injection elements, and allows for monitoring and equalization of the calorimeter response at each stage of the signal production, from scintillation light to digitization. Based on LHC Run 1 experience, several calibration systems were improved for Run 2. The lessons learned, the modifications, and the current LHC Run 2 performance are discussed.

  7. Data acquisition and processing in the ATLAS tile calorimeter phase-II upgrade demonstrator

    NASA Astrophysics Data System (ADS)

    Valero, A.; Tile Calorimeter System, ATLAS

    2017-10-01

    The LHC has planned a series of upgrades culminating in the High Luminosity LHC which will have an average luminosity 5-7 times larger than the nominal Run 2 value. The ATLAS Tile Calorimeter will undergo an upgrade to accommodate the HL-LHC parameters. The TileCal readout electronics will be redesigned, introducing a new readout strategy. A Demonstrator program has been developed to evaluate the new proposed readout architecture and prototypes of all the components. In the Demonstrator, the detector data received in the Tile PreProcessors (PPr) are stored in pipeline buffers and upon the reception of an external trigger signal the data events are processed, packed and readout in parallel through the legacy ROD system, the new Front-End Link eXchange system and an ethernet connection for monitoring purposes. This contribution describes in detail the data processing and the hardware, firmware and software components of the TileCal Demonstrator readout system.

  8. Application of Terahertz Radiation to the Detection of Corrosion Under the Shuttle's Thermal Protection System

    NASA Astrophysics Data System (ADS)

    Madaras, Eric I.; Anastasi, Robert F.; Smith, Stephen W.; Seebo, Jeffrey P.; Walker, James L.; Lomness, Janice K.; Hintze, Paul E.; Kammerer, Catherine C.; Winfree, William P.; Russell, Richard W.

    2008-02-01

    There is currently no method for detecting corrosion under Shuttle tiles except for the expensive process of tile removal and replacement; hence NASA is investigating new NDE methods for detecting hidden corrosion. Time domain terahertz radiation has been applied to corrosion detection under tiles in samples ranging from small lab samples to a Shuttle with positive results. Terahertz imaging methods have been able to detect corrosion at thicknesses of 5 mils or greater under 1" thick Shuttle tiles and 7-12 mils or greater under 2" thick Shuttle tiles.

  9. NASA TileWorld manual (system version 2.2)

    NASA Technical Reports Server (NTRS)

    Philips, Andrew B.; Bresina, John L.

    1991-01-01

    The commands are documented of the NASA TileWorld simulator, as well as providing information about how to run it and extend it. The simulator, implemented in Common Lisp with Common Windows, encodes a particular range in a spectrum of domains, for controllable research experiments. TileWorld consists of a two dimensional grid of cells, a set of polygonal tiles, and a single agent which can grasp and move tiles. In addition to agent executable actions, there is an external event over which the agent has not control; this event correspond to a 'gust of wind'.

  10. Application of Terahertz Radiation to the Detection of Corrosion under the Shuttle's Thermal Protection System

    NASA Technical Reports Server (NTRS)

    Madaras, Eric I.; Anastasi, Robert F.; Smith, Stephen W.; Seebo, Jeffrey P.; Walker, James L.; Lomness, Janice K.; Hintze, Paul E.; Kammerer, Catherine C.; Winfree, William P.; Russell, Richard W.

    2007-01-01

    There is currently no method for detecting corrosion under Shuttle tiles except for the expensive process of tile removal and replacement; hence NASA is investigating new NDE methods for detecting hidden corrosion. Time domain terahertz radiation has been applied to corrosion detection under tiles in samples ranging from small lab samples to a Shuttle with positive results. Terahertz imaging methods have been able to detect corrosion at thicknesses of 5 mils or greater under 1" thick Shuttle tiles and 7-12 mils or greater under 2" thick Shuttle tiles.

  11. Condensate oscillations in a Penrose tiling lattice

    NASA Astrophysics Data System (ADS)

    Akdeniz, Z.; Vignolo, P.

    2017-07-01

    We study the dynamics of a Bose-Einstein condensate subject to a particular Penrose tiling lattice. In such a lattice, the potential energy at each site depends on the neighbour sites, accordingly to the model introduced by Sutherland [16]. The Bose-Einstein wavepacket, initially at rest at the lattice symmetry center, is released. We observe a very complex time-evolution that strongly depends on the symmetry center (two choices are possible), on the potential energy landscape dispersion, and on the interaction strength. The condensate-width oscillates at different frequencies and we can identify large-frequency reshaping oscillations and low-frequency rescaling oscillations. We discuss in which conditions these oscillations are spatially bounded, denoting a self-trapping dynamics.

  12. Aerothermal tests of quilted dome models on a flat plate at a Mach number of 6.5

    NASA Technical Reports Server (NTRS)

    Glass, Christopher E.; Hunt, L. Roane

    1988-01-01

    Aerothermal tests were conducted in the NASA Langley 8 Foot High Temperature Tunnel (8'HTT) at a Mach number of 6.5 on simulated arrays of thermally bowed metallic thermal protection system (TPS) tiles at an angle of attack of 5 deg. Detailed surface pressures and heating rates were obtained for arrays aligned with the flow and skewed 45 deg diagonally to the flow with nominal bowed heights of 0.1, 0.2, and 0.4 inch submerged in both laminar and turbulent boundary layers. Aerothermal tests were made at a nominal total temperature of 3300 R, a total pressure of 400 psia, a total enthalpy of 950 Btu/lbm, a dynamic pressure of 2.7 psi, and a unit Reynolds number of 400,000 per foot. The experimental results form a data base that can be used to help protect aerothermal load increases from bowed arrays of TPS tiles.

  13. Illinois drainage water management demonstration project

    USGS Publications Warehouse

    Pitts, D.J.; Cooke, R.; Terrio, P.J.; ,

    2004-01-01

    Due to naturally high water tables and flat topography, there are approximately 4 million ha (10 million ac) of farmland artificially drained with subsurface (tile) systems in Illinois. Subsurface drainage is practiced to insure trafficable field conditions for farm equipment and to reduce crop stress from excess water within the root zone. Although drainage is essential for economic crop production, there have been some significant environmental costs. Tile drainage systems tend to intercept nutrient (nitrate) rich soil-water and shunt it to surface water. Data from numerous monitoring studies have shown that a significant amount of the total nitrate load in Illinois is being delivered to surface water from tile drainage systems. In Illinois, these drainage systems are typically installed without control mechanisms and allow the soil to drain whenever the water table is above the elevation of the tile outlet. An assessment of water quality in the tile drained areas of Illinois showed that approximately 50 percent of the nitrate load was being delivered through the tile systems during the fallow period when there was no production need for drainage to occur. In 1998, a demonstration project to introduce drainage water management to producers in Illinois was initiated by NRCS4 An initial aspect of the project was to identify producers that were willing to manage their drainage system to create a raised water table during the fallow (November-March) period. Financial assistance from two federal programs was used to assist producers in retrofitting the existing drainage systems with control structures. Growers were also provided guidance on the management of the structures for both water quality and production benefits. Some of the retrofitted systems were monitored to determine the effect of the practice on water quality. This paper provides background on the water quality impacts of tile drainage in Illinois, the status of the demonstration project, preliminary monitoring results, and other observations.

  14. Hypothetical Reentry Thermostructural Performance of Space Shuttle Orbiter With Missing or Eroded Thermal Protection Tiles

    NASA Technical Reports Server (NTRS)

    Ko, William L.; Gong, Leslie; Quinn, Robert D.

    2004-01-01

    This report deals with hypothetical reentry thermostructural performance of the Space Shuttle orbiter with missing or eroded thermal protection system (TPS) tiles. The original STS-5 heating (normal transition at 1100 sec) and the modified STS-5 heating (premature transition at 800 sec) were used as reentry heat inputs. The TPS missing or eroded site is assumed to be located at the center or corner (spar-rib juncture) of the lower surface of wing midspan bay 3. For cases of missing TPS tiles, under the original STS-5 heating, the orbiter can afford to lose only one TPS tile at the center or two TPS tiles at the corner (spar-rib juncture) of the lower surface of wing midspan bay 3. Under modified STS-5 heating, the orbiter cannot afford to lose even one TPS tile at the center or at the corner of the lower surface of wing midspan bay 3. For cases of eroded TPS tiles, the aluminum skin temperature rises relatively slowly with the decreasing thickness of the eroded central or corner TPS tile until most of the TPS tile is eroded away, and then increases exponentially toward the missing tile case.

  15. Understanding the Elementary Steps in DNA Tile-Based Self-Assembly.

    PubMed

    Jiang, Shuoxing; Hong, Fan; Hu, Huiyu; Yan, Hao; Liu, Yan

    2017-09-26

    Although many models have been developed to guide the design and implementation of DNA tile-based self-assembly systems with increasing complexity, the fundamental assumptions of the models have not been thoroughly tested. To expand the quantitative understanding of DNA tile-based self-assembly and to test the fundamental assumptions of self-assembly models, we investigated DNA tile attachment to preformed "multi-tile" arrays in real time and obtained the thermodynamic and kinetic parameters of single tile attachment in various sticky end association scenarios. With more sticky ends, tile attachment becomes more thermostable with an approximately linear decrease in the free energy change (more negative). The total binding free energy of sticky ends is partially compromised by a sequence-independent energy penalty when tile attachment forms a constrained configuration: "loop". The minimal loop is a 2 × 2 tetramer (Loop4). The energy penalty of loops of 4, 6, and 8 tiles was analyzed with the independent loop model assuming no interloop tension, which is generalizable to arbitrary tile configurations. More sticky ends also contribute to a faster on-rate under isothermal conditions when nucleation is the rate-limiting step. Incorrect sticky end contributes to neither the thermostability nor the kinetics. The thermodynamic and kinetic parameters of DNA tile attachment elucidated here will contribute to the future improvement and optimization of tile assembly modeling, precise control of experimental conditions, and structural design for error-free self-assembly.

  16. Lozenge Tiling Dynamics and Convergence to the Hydrodynamic Equation

    NASA Astrophysics Data System (ADS)

    Laslier, Benoît; Toninelli, Fabio Lucio

    2018-03-01

    We study a reversible continuous-time Markov dynamics of a discrete (2 + 1)-dimensional interface. This can be alternatively viewed as a dynamics of lozenge tilings of the {L× L} torus, or as a conservative dynamics for a two-dimensional system of interlaced particles. The particle interlacement constraints imply that the equilibrium measures are far from being product Bernoulli: particle correlations decay like the inverse distance squared and interface height fluctuations behave on large scales like a massless Gaussian field. We consider a particular choice of the transition rates, originally proposed in Luby et al. (SIAM J Comput 31:167-192, 2001): in terms of interlaced particles, a particle jump of length n that preserves the interlacement constraints has rate 1/(2 n). This dynamics presents special features: the average mutual volume between two interface configurations decreases with time (Luby et al. 2001) and a certain one-dimensional projection of the dynamics is described by the heat equation (Wilson in Ann Appl Probab 14:274-325, 2004). In this work we prove a hydrodynamic limit: after a diffusive rescaling of time and space, the height function evolution tends as L\\to∞ to the solution of a non-linear parabolic PDE. The initial profile is assumed to be C 2 differentiable and to contain no "frozen region". The explicit form of the PDE was recently conjectured (Laslier and Toninelli in Ann Henri Poincaré Theor Math Phys 18:2007-2043, 2017) on the basis of local equilibrium considerations. In contrast with the hydrodynamic equation for the Langevin dynamics of the Ginzburg-Landau model (Funaki and Spohn in Commun Math Phys 85:1-36, 1997; Nishikawa in Commun Math Phys 127:205-227, 2003), here the mobility coefficient turns out to be a non-trivial function of the interface slope.

  17. Self assembly of rectangular shapes on concentration programming and probabilistic tile assembly models.

    PubMed

    Kundeti, Vamsi; Rajasekaran, Sanguthevar

    2012-06-01

    Efficient tile sets for self assembling rectilinear shapes is of critical importance in algorithmic self assembly. A lower bound on the tile complexity of any deterministic self assembly system for an n × n square is [Formula: see text] (inferred from the Kolmogrov complexity). Deterministic self assembly systems with an optimal tile complexity have been designed for squares and related shapes in the past. However designing [Formula: see text] unique tiles specific to a shape is still an intensive task in the laboratory. On the other hand copies of a tile can be made rapidly using PCR (polymerase chain reaction) experiments. This led to the study of self assembly on tile concentration programming models. We present two major results in this paper on the concentration programming model. First we show how to self assemble rectangles with a fixed aspect ratio ( α:β ), with high probability, using Θ( α + β ) tiles. This result is much stronger than the existing results by Kao et al. (Randomized self-assembly for approximate shapes, LNCS, vol 5125. Springer, Heidelberg, 2008) and Doty (Randomized self-assembly for exact shapes. In: proceedings of the 50th annual IEEE symposium on foundations of computer science (FOCS), IEEE, Atlanta. pp 85-94, 2009)-which can only self assembly squares and rely on tiles which perform binary arithmetic. On the other hand, our result is based on a technique called staircase sampling . This technique eliminates the need for sub-tiles which perform binary arithmetic, reduces the constant in the asymptotic bound, and eliminates the need for approximate frames (Kao et al. Randomized self-assembly for approximate shapes, LNCS, vol 5125. Springer, Heidelberg, 2008). Our second result applies staircase sampling on the equimolar concentration programming model (The tile complexity of linear assemblies. In: proceedings of the 36th international colloquium automata, languages and programming: Part I on ICALP '09, Springer-Verlag, pp 235-253, 2009), to self assemble rectangles (of fixed aspect ratio) with high probability. The tile complexity of our algorithm is Θ(log( n )) and is optimal on the probabilistic tile assembly model (PTAM)- n being an upper bound on the dimensions of a rectangle.

  18. Simulating the Effects of Drainage and Agriculture on Hydrology and Sediment in the Minnesota River Basin

    NASA Astrophysics Data System (ADS)

    Downer, C. W.; Pradhan, N. R.; Skahill, B. E.; Banitt, A. M.; Eggers, G.; Pickett, R. E.

    2014-12-01

    Throughout the Midwest region of the United States, slopes are relatively flat, soils tend to have low permeability, and local water tables are high. In order to make the region suitable for agriculture, farmers have installed extensive networks of ditches to drain off excess surface water and subsurface tiles to lower the water table and remove excess soil water in the root zone that can stress common row crops, such as corn and soybeans. The combination of tiles, ditches, and intensive agricultural land practices radically alters the landscape and hydrology. Within the watershed, tiles have outlets to both the ditch/stream network as well as overland locations, where the tile discharge appears to initiate gullies and exacerbate overland erosion. As part of the Minnesota River Basin Integrated Study we are explicitly simulating the tile and drainage systems in the watershed at multiple scales using the physics-based watershed model GSSHA (Gridded Surface Subsurface Hydrologic Analysis). The tile drainage system is simulated as a network of pipes that collect water from the local water table. Within the watershed, testing of the methods on smaller basins shows the ability of the model to simulate tile flow, however, application at the larger scale is hampered by the computational burden of simulating the flow in the complex tile drain networks that drain the agricultural fields. Modeling indicates the subsurface drains account for approximately 40% of the stream flow in the Seven Mile Creek sub-basin account in the late spring and early summer when the tile is flowing. Preliminary results indicate that agricultural tile drains increase overland erosion in the Seven Mile Creek watershed.

  19. Pharmaceutical and personal care products in tile drainage following land application of municipal biosolids.

    PubMed

    Lapen, D R; Topp, E; Metcalfe, C D; Li, H; Edwards, M; Gottschall, N; Bolton, P; Curnoe, W; Payne, M; Beck, A

    2008-07-25

    Land application of municipal biosolids (sewage) is a common farming practice in many parts of the world. There is potential for transport of pharmaceuticals and personal care products (PPCPs) from agricultural fields to adjacent surface waters via tile drainage systems. In this study, liquid municipal biosolids (LMB) (total solids=11,933 mg L(-1)), supplemented with selected PPCPs and the fluorescent dye tracer rhodamine WT (RWT), were applied to tile drained fields using two land application approaches. Objectives included evaluating the relative benefits of land application practices with respect to reducing PPCP loadings to tile drains, evaluating PPCP persistence in tile water, and determining whether rhodamine WT can be used to estimate PPCP mass loads in tile. The PPCPs examined included an antibacterial agent used in personal care products (triclosan), a metabolite of nicotine (cotinine), and a variety of drugs including two sulfonamide antimicrobials (sulfapyridine, sulfamethoxazole), a beta-blocker (atenolol), an anti-epileptic (carbamazepine), an antidepressant (fluoxetine), analgesic/anti-inflammatories (acetaminophen, naproxen, ibuprofen), and a lipid-regulator (gemfibrozil). Maximum observed PPCP concentrations in the spiked LMB were about 10(3) ng g(-1) dry weight. PPCPs were shown to move rapidly via soil macropores to tile drains within minutes of the land application. Maximum observed PPCP concentrations in tile effluent associated with the LMB application-induced tile flow event were approximately 10(1) to 10(3) ng L(-1). PPCP mass loads, for the application-induced tile-hydrograph event, were significantly (p<0.1) higher for surface spreading over non-tilled soil (incorporation tillage occurring 20 h post-application), relative to aerating soil immediately prior to surface spreading using an AerWay slurry deposition system. PPCP concentrations that were detected above the limit of quantitation (LOQ) in tile water during several precipitation-induced tile flow events that occurred post-application, included: triclosan (max. approximately 1.5 x 10(2) ng L(-1)), carbamazepine (max. approximately 7 x 10(1) ng L(-1)), atenolol (max approximately 4 x 10(1) ng L(-1)), and cotinine (max approximately 2 x 10(1) ng L(-1)). In spite of their presence in biosolids, the other PPCPs were not observed above LOQ concentrations during these events. PPCP concentrations were predicted from RWT concentrations over a 40 day study period. Tile mass loads as a percent of PPCP mass applied to soil ranged from 4.2%+/-SD of 9.2% to 7.1%+/-10.9% for the AerWay system and surface spreading plus incorporation treatments, respectively.

  20. Accounting for the risks of phosphorus losses through tile drains in a phosphorus index.

    PubMed

    Reid, D Keith; Ball, Bonnie; Zhang, T Q

    2012-01-01

    Tile drainage systems have been identified as a significant conduit for phosphorus (P) losses to surface water, but P indices do not currently account for this transport pathway in a meaningful way. Several P indices mention tile drains, but most account for either the reduction in surface runoff or the enhanced transport through tiles rather than both simultaneously. A summary of the current state of how tile drains are accounted for within P indices is provided, and the challenges in predicting the risk of P losses through tile drains that are relative to actual losses are discussed. A framework for a component P Index is described, along with a proposal to incorporate predictions of losses through tile drains as a component within this framework. Options for calibrating and testing this component are discussed. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  1. Integrated Solar-Energy-Harvesting and -Storage Device

    NASA Technical Reports Server (NTRS)

    whitacre, Jay; Fleurial, Jean-Pierre; Mojarradi, Mohammed; Johnson, Travis; Ryan, Margaret Amy; Bugga, Ratnakumar; West, William; Surampudi, Subbarao; Blosiu, Julian

    2004-01-01

    A modular, integrated, completely solid-state system designed to harvest and store solar energy is under development. Called the power tile, the hybrid device consists of a photovoltaic cell, a battery, a thermoelectric device, and a charge-control circuit that are heterogeneously integrated to maximize specific energy capacity and efficiency. Power tiles could be used in a variety of space and terrestrial environments and would be designed to function with maximum efficiency in the presence of anticipated temperatures, temperature gradients, and cycles of sunlight and shadow. Because they are modular in nature, one could use a single power tile or could construct an array of as many tiles as needed. If multiple tiles are used in an array, the distributed and redundant nature of the charge control and distribution hardware provides an extremely fault-tolerant system. The figure presents a schematic view of the device.

  2. Boundary Layer Transition Protuberance Tests at NASA JSC Arc-Jet Facility

    NASA Technical Reports Server (NTRS)

    Larin, M. E.; Marichalar, J. J.; Kinder, G. R.; Campbell, C. H.; Riccio, J. R.; Nquyen, T. Q.; DelPapa, S. V.; Pulsonetti, M. V.

    2009-01-01

    A series of arc-jet tests in support of the Shuttle Orbiter Boundary Layer Transition flight experiment was conducted in the Channel Nozzle of the NASA Johnson Space Center Atmospheric Reentry Materials and Structures Facility. The boundary layer trip was a protrusion of a certain height and geometry fabricated as part of a 6"x6" tile insert, a special test article made of the Boeing Rigid Insulation tile material and coated with the Reaction Cured Glass used for the bottom fuselage tiles of the Space Shuttle Orbiter. A total of five such tile inserts were manufactured: four with the 0.25-in. trip height, and one with the 0.35-in. trip height. The tile inserts were interchangeably installed in the center of the 24"x24" variable configuration tile array mounted in the 24"x24" test section of the channel nozzle. The objectives of the test series were to demonstrate that the boundary layer trip can safely withstand the Space Shuttle Orbiter flight-like re-entry environments and provide temperature data on the protrusion surface, surfaces of the nearby tiles upstream and downstream of the trip, as well as the bond line between the tiles and the structure. The targeted test environments were defined for the tip of the protrusion, away from the nominal surface of the tile array. The arc jet test conditions were approximated in order to produce the levels of the free stream total enthalpy at the protrusion height similar to those expected in flight. The test articles were instrumented with surface, sidewall and bond line thermocouples. Additionally, Tempilaq temperature-indicating paint was applied to the nominal tiles of the tile array in locations not interfering with the protrusion trip. Five different grades of paint were used that disintegrate at different temperatures between 1500 and 2000 deg F. The intent of using the paint was to gauge the RCG-coated tile surface temperature, as well as determine its usefulness for a flight experiment. This paper provides an overview of the channel nozzle arc jet, test articles and test conditions, as well as the results of the arc-jet tests including the measured temperature response of the test articles, their pre- and post-test surface scans, condition of the thermal paint, and continents on the protrusion tip heating achieved in tests compared to the computational fluid dynamics predictions.

  3. Calibration and performance of the ATLAS Tile Calorimeter during the LHC Run 2

    NASA Astrophysics Data System (ADS)

    Cerda Alberich, L.

    2018-02-01

    The Tile Calorimeter (TileCal) is the hadronic sampling calorimeter of the ATLAS experiment at the Large Hadron Collider (LHC). TileCal uses iron absorbers and scintillators as active material and it covers the central region | η| < 1.7. Jointly with the other sub-detectors it is designed for measurements of hadrons, jets, tau-particles and missing transverse energy. It also assists in muon identification. TileCal is regularly monitored and calibrated by several different calibration systems: a Cs radioactive source, a laser light system to check the PMT response, and a charge injection system (CIS) to check the front-end electronics. These calibration systems, in conjunction with data collected during proton-proton collisions, Minimum Bias (MB) events, provide extensive monitoring of the instrument and a means for equalizing the calorimeter response at each stage of the signal propagation. The performance of the calorimeter has been established with cosmic ray muons and the large sample of the proton-proton collisions and compared to Monte Carlo (MC) simulations. The response of high momentum isolated muons is also used to study the energy response at the electromagnetic scale, isolated hadrons are used as a probe of the hadronic response. The calorimeter time resolution is studied with multijet events. A description of the different TileCal calibration systems and the results on the calorimeter performance during the LHC Run 2 are presented. The results on the pile-up noise and response uniformity studies are also discussed.

  4. Major Disruptions and Other Issues Driving the Design of the Ignitor Plasma Chamber

    NASA Astrophysics Data System (ADS)

    Ramogida, G.; Frosi, P.; Coppi, B.

    2012-10-01

    The Plasma Chamber of the Ignitor machine is designed according to the information available about electromagnetic loads coming from the experimental knowledge and the increasingly accurate numerical models of the eddy and halo currents resulting from the worst disruption events in existing machines. The developed models deal with static, dynamic and modal analysis. The loads during nominal operations and also those arising from plasma disruptions, by far the most important ones, have been taken into account, as well as the design problems arising from the Mo tiles in the inboard edge of the vacuum vessel, the Faraday shields covering the 6 ports devoted to the ICRH system and, finally, the reaction forces coming from the regions of constraints with the C-Clamps (the retaining structure that support the plasma chamber both statically and dynamically). The plasma chamber has to perform several additional functions, such as to keep the vacuum, be bakeable, and support the set of plates that carry the Mo tiles facing the plasma column. According to the present design the chamber is made of Inconel and has a thickness varying from 26 to 52 mm.

  5. Seasonal regulation of herbivory and nutrient effects on macroalgal recruitment and succession in a Florida coral reef

    PubMed Central

    Collado-Vides, Ligia; Burkepile, Deron E.

    2016-01-01

    Herbivory and nutrient enrichment are drivers of benthic dynamics of coral reef macroalgae; however, their impact may vary seasonally. In this study we evaluated the effects of herbivore pressure, nutrient availability and potential propagule supply on seasonal recruitment and succession of macroalgal communities on a Florida coral reef. Recruitment tiles, replaced every three months, and succession tiles, kept in the field for nine months, were established in an ongoing factorial nutrient enrichment-herbivore exclusion experiment. The ongoing experiment had already created very different algal communities across the different herbivory and nutrient treatments. We tracked algal recruitment, species richness, and species abundance through time. Our results show seasonal variation in the effect of herbivory and nutrient availability on recruitment of coral reef macroalgae. In the spring, when there was higher macroalgal species richness and abundance of recruits, herbivory appeared to have more control on macroalgal community structure than did nutrients. In contrast, there was no effect of either herbivory or nutrient enrichment on macroalgal communities on recruitment tiles in cooler seasons. The abundance of recruits on tiles was positively correlated with the abundance of algal in the ongoing, established experiment, suggesting that propagule abundance is likely a strong influence on algal recruitment and early succession. Results of the present study suggest that abundant herbivorous fishes control recruitment and succession of macroalgae, particularly in the warm season when macroalgal growth is higher. However, herbivory appears less impactful on algal recruitment and community dynamics in cooler seasons. Ultimately, our data suggest that the timing of coral mortality (e.g., summer vs. winter mortality) and freeing of benthic space may strongly influence the dynamics of algae that colonize open space. PMID:27833810

  6. Seasonal regulation of herbivory and nutrient effects on macroalgal recruitment and succession in a Florida coral reef.

    PubMed

    Duran, Alain; Collado-Vides, Ligia; Burkepile, Deron E

    2016-01-01

    Herbivory and nutrient enrichment are drivers of benthic dynamics of coral reef macroalgae; however, their impact may vary seasonally. In this study we evaluated the effects of herbivore pressure, nutrient availability and potential propagule supply on seasonal recruitment and succession of macroalgal communities on a Florida coral reef. Recruitment tiles, replaced every three months, and succession tiles, kept in the field for nine months, were established in an ongoing factorial nutrient enrichment-herbivore exclusion experiment. The ongoing experiment had already created very different algal communities across the different herbivory and nutrient treatments. We tracked algal recruitment, species richness, and species abundance through time. Our results show seasonal variation in the effect of herbivory and nutrient availability on recruitment of coral reef macroalgae. In the spring, when there was higher macroalgal species richness and abundance of recruits, herbivory appeared to have more control on macroalgal community structure than did nutrients. In contrast, there was no effect of either herbivory or nutrient enrichment on macroalgal communities on recruitment tiles in cooler seasons. The abundance of recruits on tiles was positively correlated with the abundance of algal in the ongoing, established experiment, suggesting that propagule abundance is likely a strong influence on algal recruitment and early succession. Results of the present study suggest that abundant herbivorous fishes control recruitment and succession of macroalgae, particularly in the warm season when macroalgal growth is higher. However, herbivory appears less impactful on algal recruitment and community dynamics in cooler seasons. Ultimately, our data suggest that the timing of coral mortality (e.g., summer vs. winter mortality) and freeing of benthic space may strongly influence the dynamics of algae that colonize open space.

  7. Use of biochar amendments for removing bacteria from simulated tile-drainage waters

    USDA-ARS?s Scientific Manuscript database

    The addition of biochar has been shown to increase bacterial removal rates by several orders of magnitude in sand-packed columns, suggesting that biochar may be a suitable amendment for use in end-of-tile filter systems to remove indicator and pathogenic microorganisms in tile-drainage waters. Addit...

  8. Thermal Structure Analysis of SIRCA Tile for X-34 Wing Leading Edge TPS

    NASA Technical Reports Server (NTRS)

    Milos, Frank S.; Squire, Thomas H.; Rasky, Daniel J. (Technical Monitor)

    1997-01-01

    This paper will describe in detail thermal/structural analyses of SIRCA tiles which were performed at NASA Ames under the The Tile Analysis Task of the X-34 Program. The analyses used the COSMOS/M finite element software to simulate the material response in arc-jet tests, mechanical deflection tests, and the performance of candidate designs for the TPS system. Purposes of the analysis were to verify thermal and structural models for the SIRCA tiles, to establish failure criteria for stressed tiles, to simulate the TPS response under flight aerothermal and mechanical load, and to confirm that adequate safety margins exist for the actual TPS design.

  9. The ATLAS tile calorimeter performance at the LHC

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Calkins, R.

    The Tile Calorimeter (TileCal), the central section of the hadronic calorimeter of the ATLAS experiment, is a key detector component to detect hadrons, jets and taus and to measure the missing transverse energy. Due to the very good muon signal to noise ratio it assists the spectrometer in the identification and reconstruction of muons. TileCal is built of steel and scintillating tiles coupled to optical fibers and read out by photomultipliers. The calorimeter is equipped with systems that allow to monitor and to calibrate each stage of the read out system exploiting different signal sources: laser light, charge injection andmore » a radioactive source. The performance of the calorimeter has been measured and monitored using calibration data, random triggered data, cosmic muons and more importantly LHC collision events. The results presented here assess the absolute energy scale calibration precision, the energy and timing uniformity and the synchronization precision. The ensemble of the results demonstrates a very good understanding of the performance of the Tile Calorimeter that is proved to be well within the design expectations. (authors)« less

  10. A novel explicit approach to model bromide and pesticide transport in connected soil structures

    NASA Astrophysics Data System (ADS)

    Klaus, J.; Zehe, E.

    2011-07-01

    The present study tests whether an explicit treatment of worm burrows and tile drains as connected structures is feasible for simulating water flow, bromide and pesticide transport in structured heterogeneous soils at hillslope scale. The essence is to represent worm burrows as morphologically connected paths of low flow resistance in a hillslope model. A recent Monte Carlo study (Klaus and Zehe, 2010, Hydrological Processes, 24, p. 1595-1609) revealed that this approach allowed successful reproduction of tile drain event discharge recorded during an irrigation experiment at a tile drained field site. However, several "hillslope architectures" that were all consistent with the available extensive data base allowed a good reproduction of tile drain flow response. Our second objective was thus to find out whether this "equifinality" in spatial model setups may be reduced when including bromide tracer data in the model falsification process. We thus simulated transport of bromide for the 13 spatial model setups that performed best with respect to reproduce tile drain event discharge, without any further calibration. All model setups allowed a very good prediction of the temporal dynamics of cumulated bromide leaching into the tile drain, while only four of them matched the accumulated water balance and accumulated bromide loss into the tile drain. The number of behavioural model architectures could thus be reduced to four. One of those setups was used for simulating transport of Isoproturon, using different parameter combinations to characterise adsorption according to the Footprint data base. Simulations could, however, only reproduce the observed leaching behaviour, when we allowed for retardation coefficients that were very close to one.

  11. RMS/OBSS inspection of shuttle thermal tile system

    NASA Image and Video Library

    2011-02-25

    S133-E-006073 (25 Feb. 2011) --- Controlled by the STS-133 astronauts inside Discovery's cabin, the Remote Manipulator System/Orbiter Boom Sensor System (RMS/OBSS) equipped with special cameras, begins to conduct thorough inspections of the shuttle’s thermal tile system on flight day 2. Photo credit: NASA or National Aeronautics and Space Administration

  12. Transient thermal analysis of a titanium multiwall thermal protection system

    NASA Technical Reports Server (NTRS)

    Blosser, M. L.

    1982-01-01

    The application of the SPAR thermal analyzer to the thermal analysis of a thermal protection system concept is discussed. The titanium multiwall thermal protection system concept consists of alternate flat and dimpled sheets which are joined together at the crests of the dimples and formed into 30 cm by 30 cm (12 in. by 12 in.) tiles. The tiles are mechanically attached to the structure. The complex tile geometry complicates thermal analysis. Three modes of heat transfer were considered: conduction through the gas inside the tile, conduction through the metal, and radiation between the various layers. The voids between the dimpled and flat sheets were designed to be small enough so that natural convection is insignificant (e.g., Grashof number 1000). A two step approach was used in the thermal analysis of the multiwall thermal protection system. First, an effective normal (through-the-thickness) thermal conductivity was obtained from a steady state analysis using a detailed SPAR finite element model of a small symmetric section of the multiwall tile. This effective conductivity was then used in simple one dimensional finite element models for preliminary analysis of several transient heat transfer problems.

  13. Generation of Escher Arts with Dual Perception.

    PubMed

    Lin, Shih-Syun; Morace, Charles C; Lin, Chao-Hung; Hsu, Li-Fong; Lee, Tong-Yee

    2018-02-01

    Escher transmutation is a graphic art that smoothly transforms one tile pattern into another tile pattern with dual perception. A classic example is the artwork called Sky and Water, in which a compelling figure-ground arrangement is applied to portray the transmutation of a bird in sky and a fish in water. The shape of a bird is progressively deformed and dissolves into the background while the background gradually reveals the shape of a fish. This paper introduces a system to create a variety of Escher-like transmutations, which includes the algorithms for initializing a tile pattern with dual figure-ground arrangement, for searching for the best matched shape of a user-specified motif from a database, and for transforming the content and shapes of tile patterns using a content-aware warping technique. The proposed system, integrating the graphic techniques of tile initialization, shape matching, and shape warping, allows users to create various Escher-like transmutations with minimal user interaction. Experimental results and conducted user studies demonstrate the feasibility and flexibility of the proposed system in Escher art generation.

  14. Navigating the socio-bio-geo-chemistry and engineering of nitrogen management in two illinois tile-drained watersheds.

    PubMed

    David, Mark B; Flint, Courtney G; Gentry, Lowell E; Dolan, Mallory K; Czapar, George F; Cooke, Richard A; Lavaire, Tito

    2015-03-01

    Reducing nitrate loads from corn and soybean, tile-drained, agricultural production systems in the Upper Mississippi River basin is a major challenge that has not been met. We evaluated a range of possible management practices from biophysical and social science perspectives that could reduce nitrate losses from tile-drained fields in the Upper Salt Fork and Embarras River watersheds of east-central Illinois. Long-term water quality monitoring on these watersheds showed that nitrate losses averaged 30.6 and 23.0 kg nitrate N ha yr (Embarras and Upper Salt Fork watersheds, respectively), with maximum nitrate concentrations between 14 and 18 mg N L. With a series of on-farm studies, we conducted tile monitoring to evaluate several possible nitrate reduction conservation practices. Fertilizer timing and cover crops reduced nitrate losses (30% reduction in a year with large nitrate losses), whereas drainage water management on one tile system demonstrated the problems with possible retrofit designs (water flowed laterally from the drainage water management tile to the free drainage system nearby). Tile woodchip bioreactors had good nitrate removal in 2012 (80% nitrate reduction), and wetlands had previously been shown to remove nitrate (45% reductions) in the Embarras watershed. Interviews and surveys indicated strong environmental concern and stewardship ethics among landowners and farmers, but the many financial and operational constraints that they operate under limited their willingness to adopt conservation practices that targeted nitrate reduction. Under the policy and production systems currently in place, large-scale reductions in nitrate losses from watersheds such as these in east-central Illinois will be difficult. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  15. Applying Hillslope Hydrology to Bridge between Ecosystem and Grid-Scale Processes within an Earth System Model

    NASA Astrophysics Data System (ADS)

    Subin, Z. M.; Sulman, B. N.; Malyshev, S.; Shevliakova, E.

    2013-12-01

    Soil moisture is a crucial control on surface energy fluxes, vegetation properties, and soil carbon cycling. Its interactions with ecosystem processes are highly nonlinear across a large range, as both drought stress and anoxia can impede vegetation and microbial growth. Earth System Models (ESMs) generally only represent an average soil-moisture state in grid cells at scales of 50-200 km, and as a result are not able to adequately represent the effects of subgrid heterogeneity in soil moisture, especially in regions with large wetland areas. We addressed this deficiency by developing the first ESM-coupled subgrid hillslope-hydrological model, TiHy (Tiled-hillslope Hydrology), embedded within the Geophysical Fluid Dynamics Laboratory (GFDL) land model. In each grid cell, one or more representative hillslope geometries are discretized into land model tiles along an upland-to-lowland gradient. These geometries represent ~1 km hillslope-scale hydrological features and allow for flexible representation of hillslope profile and plan shapes, in addition to variation of subsurface properties among or within hillslopes. Each tile (which may represent ~100 m along the hillslope) has its own surface fluxes, vegetation state, and vertically-resolved state variables for soil physics and biogeochemistry. Resolution of water state in deep layers (~200 m) down to bedrock allows for physical integration of groundwater transport with unsaturated overlying dynamics. Multiple tiles can also co-exist at the same vertical position along the hillslope, allowing the simulation of ecosystem heterogeneity due to disturbance. The hydrological model is coupled to the vertically-resolved Carbon, Organisms, Respiration, and Protection in the Soil Environment (CORPSE) model, which captures non-linearity resulting from interactions between vertically-heterogeneous soil carbon and water profiles. We present comparisons of simulated water table depth to observations. We examine sensitivities to alternative parameterizations of hillslope geometry, macroporosity, and surface runoff / inundation, and to the choice of global topographic dataset and groundwater hydraulic conductivity distribution. Simulated groundwater dynamics among hillslopes tend to cluster into three regimes of wet and well-drained, wet but poorly-drained, and dry. In the base model configuration, near-surface gridcell-mean water tables exist in an excessively large area compared to observations, including large areas of the Eastern U.S. and Northern Europe. However, in better-drained areas, the decrease in water table depth along the hillslope gradient allows for realistic increases in ecosystem water availability and soil carbon downslope. The inclusion of subgrid hydrology can increase the equilibrium 0-2 m global soil carbon stock by a large factor, due to the nonlinear effect of anoxia. We conclude that this innovative modeling framework allows for the inclusion of hillslope-scale processes and the potential for wetland dynamics in an ESM without need for a high-resolution 3-dimensional groundwater model. Future work will include investigating the potential for future changes in land carbon fluxes caused by the effects of changing hydrological regime, particularly in peatland-rich areas poorly treated by current ESMs.

  16. Quantitative real-time PCR-based assessment of tile drainage management influences on bacterial pathogens in tile drainage and groundwater.

    PubMed

    Liu, Linda; Cloutier, Michel; Craiovan, Emilia; Edwards, Mark; Frey, Steven K; Gottschall, Natalie; Lapen, David R; Sunohara, Mark; Topp, Edward; Khan, Izhar U H

    2018-05-15

    This study compared the impact of controlled tile drainage (CD) and freely draining (FD) systems on the prevalence and quantitative real-time PCR-based enumeration of four major pathogens including Arcobacter butzleri, Campylobacter jejuni, Campylobacter coli, and Helicobacter pylori in tile- and groundwater following a fall liquid swine manure (LSM) application on clay loam field plots. Although the prevalence of all target pathogens were detected in CD and FD systems, the loads of A. butzleri, C. jejuni, and C. coli were significantly lower in CD tile-water (p<0.05), in relation to FD tile-water. However, concentrations of A. butzleri were significantly greater in CD than FD tile-water (p<0.05). In shallow groundwater (1.2m depth), concentrations of A. butzleri, C. coli, and H. pylori showed no significant difference between CD and FD plots, while C. jejuni concentrations were significantly higher in FD plots (p<0.05). No impact of CD on the H. pylori was observed since quantitative detection in tile- and groundwater was scarce. Although speculative, H. pylori occurrence may have been related to the application of municipal biosolids four years prior to the LSM experiment. Overall, CD can be used to help minimize off-field export of pathogens into surface waters following manure applications to land, thereby reducing waterborne pathogen exposure risks to humans. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  17. Reducing phosphorus loss in tile water with managed drainage in a claypan soil.

    PubMed

    Nash, Patrick R; Nelson, Kelly A; Motavalli, Peter P; Nathan, Manjula; Dudenhoeffer, Chris

    2015-03-01

    Installing subsurface tile drain systems in poorly drained claypan soils to improve corn ( L.) yields could potentially increase environmental phosphorus (P) loss through the tile drainage system. The objectives of the study were to quantify the average concentration and loss of ortho-P in tile drain water from a claypan soil and to determine whether managed subsurface drainage (MD) could reduce ortho-P loss in tile water compared with free subsurface drainage (FD). Flow-weighted ortho-P concentration in the tile water was significantly lower with MD (0.09 mg L) compared with that of FD (0.15 mg L). Ortho-P loss in the tile water of this study was reduced with MD (36 g ha) by 80% compared with FD (180 g ha). Contrary to previous research, reduced ortho-P loss observed over the 4-yr study was not solely due to the reduced amount of water drained annually (63%) with MD compared with FD. During the spring period, when flow was similar between MD and FD, the concentration of ortho-P in the tile water generally was lower with MD compared with FD, which resulted in significantly less ortho-P loss with MD. We speculate that MD's ability to conserve water during the dry summer months increased corn's uptake of water and P, which reduced the amount of P available for leaching loss in the subsequent springs. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  18. Upland and in-stream controls on baseflow nutrient dynamics in tile-drained agroecosystem watersheds

    USDA-ARS?s Scientific Manuscript database

    Controls on baseflow nutrient concentrations in agroecosystems are poorly characterized in comparison with storm events. However, in landscapes with low residence times (e.g., rivers and reservoirs), baseflow nutrient concentration dynamics during sensitive timeframes can drive deleterious environm...

  19. Global helium particle balance in LHD

    NASA Astrophysics Data System (ADS)

    Motojima, G.; Masuzaki, S.; Tokitani, M.; Kasahara, H.; Yoshimura, Y.; Kobayashi, M.; Sakamoto, R.; Morisaki, T.; Miyazawa, J.; Akiyama, T.; Ohno, N.; Mutoh, T.; Yamada, H.; LHD Experiment Group

    2015-08-01

    Global helium particle balance in long-pulse discharges is analyzed for the first time in the Large Helical Device (LHD) with the plasma-facing components of the first wall and the divertor tiles composed of stainless steel and carbon, respectively. During the 2-min discharge sustained by ion cyclotron resonance heating (ICRH) and electron cyclotron heating (ECH), helium is observed to be highly retained in the wall (regarded as both the first wall and the divertor tiles). Almost all (about 96%) puffed helium particles (1.3 × 1022 He) are absorbed in the wall near the end of the discharge. Even though a dynamic retention is eliminated, 56% is still absorbed. The analysis is also applied to longer pulse discharges over 40 min by ICRH and ECH, indicating that the helium wall retention is dynamically changed in time. At the initial phase of the discharge, a mechanism for adsorbing helium other than dynamical retention is invoked.

  20. Orbiter thermal pressure drop characteristics for shuttle orbiter thermal protection system components: High density tile, low density tile, densified low density tile, and strain isolation pad

    NASA Technical Reports Server (NTRS)

    Lawing, P. L.; Nystrom, D. M.

    1980-01-01

    Pressure drop tests were conducted on available samples of low and high density tile, densified low density tile, and strain isolation pads. The results are presented in terms of pressure drop, material thickness and volume flow rate. Although the test apparatus was only capable of a small part of the range of conditions to be encountered in a Shuttle Orbiter flight, the data serve to determine the type of flow characteristics to be expected for each material type tested; the measured quantities also should serve as input for initial venting and flow through analysis.

  1. Self assembly of rectangular shapes on concentration programming and probabilistic tile assembly models

    PubMed Central

    Rajasekaran, Sanguthevar

    2013-01-01

    Efficient tile sets for self assembling rectilinear shapes is of critical importance in algorithmic self assembly. A lower bound on the tile complexity of any deterministic self assembly system for an n × n square is Ω(log(n)log(log(n))) (inferred from the Kolmogrov complexity). Deterministic self assembly systems with an optimal tile complexity have been designed for squares and related shapes in the past. However designing Θ(log(n)log(log(n))) unique tiles specific to a shape is still an intensive task in the laboratory. On the other hand copies of a tile can be made rapidly using PCR (polymerase chain reaction) experiments. This led to the study of self assembly on tile concentration programming models. We present two major results in this paper on the concentration programming model. First we show how to self assemble rectangles with a fixed aspect ratio (α:β), with high probability, using Θ(α + β) tiles. This result is much stronger than the existing results by Kao et al. (Randomized self-assembly for approximate shapes, LNCS, vol 5125. Springer, Heidelberg, 2008) and Doty (Randomized self-assembly for exact shapes. In: proceedings of the 50th annual IEEE symposium on foundations of computer science (FOCS), IEEE, Atlanta. pp 85–94, 2009)—which can only self assembly squares and rely on tiles which perform binary arithmetic. On the other hand, our result is based on a technique called staircase sampling. This technique eliminates the need for sub-tiles which perform binary arithmetic, reduces the constant in the asymptotic bound, and eliminates the need for approximate frames (Kao et al. Randomized self-assembly for approximate shapes, LNCS, vol 5125. Springer, Heidelberg, 2008). Our second result applies staircase sampling on the equimolar concentration programming model (The tile complexity of linear assemblies. In: proceedings of the 36th international colloquium automata, languages and programming: Part I on ICALP ’09, Springer-Verlag, pp 235–253, 2009), to self assemble rectangles (of fixed aspect ratio) with high probability. The tile complexity of our algorithm is Θ(log(n)) and is optimal on the probabilistic tile assembly model (PTAM)—n being an upper bound on the dimensions of a rectangle. PMID:24311993

  2. Color machine vision system for process control in the ceramics industry

    NASA Astrophysics Data System (ADS)

    Penaranda Marques, Jose A.; Briones, Leoncio; Florez, Julian

    1997-08-01

    This paper is focused on the design of a machine vision system to solve a problem found in the manufacturing process of high quality polished porcelain tiles. This consists of sorting the tiles according to the criteria 'same appearance to the human eye' or in other words, by color and visual texture. In 1994 this problem was tackled and led to a prototype which became fully operational at production scale in a manufacturing plant, named Porcelanatto, S.A. The system has evolved and has been adapted to meet the particular needs of this manufacturing company. Among the main issues that have been improved, it is worth pointing out: (1) improvement to discern subtle variations in color or texture, which are the main features of the visual appearance; (2) inspection time reduction, as a result of algorithm optimization and the increasing computing power. Thus, 100 percent of the production can be inspected, reaching a maximum of 120 tiles/sec.; (3) adaptation to the different types and models of tiles manufactured. The tiles vary not only in their visible patterns but also in dimensions, formats, thickness and allowances. In this sense, one major problem has been reaching an optimal compromise: The system must be sensitive enough to discern subtle variations in color, but at the same time insensitive thickness variations in the tiles. The following parts have been used to build the system: RGB color line scan camera, 12 bits per channel, PCI frame grabber, PC, fiber optic based illumination and the algorithm which will be explained in section 4.

  3. Comparison of performance of tile drainage routines in SWAT 2009 and 2012 in an extensively tile-drained watershed in the Midwest

    NASA Astrophysics Data System (ADS)

    Guo, Tian; Gitau, Margaret; Merwade, Venkatesh; Arnold, Jeffrey; Srinivasan, Raghavan; Hirschi, Michael; Engel, Bernard

    2018-01-01

    Subsurface tile drainage systems are widely used in agricultural watersheds in the Midwestern US and enable the Midwest area to become highly productive agricultural lands, but can also create environmental problems, for example nitrate-N contamination associated with drainage waters. The Soil and Water Assessment Tool (SWAT) has been used to model watersheds with tile drainage. SWAT2012 revisions 615 and 645 provide new tile drainage routines. However, few studies have used these revisions to study tile drainage impacts at both field and watershed scales. Moreover, SWAT2012 revision 645 improved the soil moisture based curve number calculation method, which has not been fully tested. This study used long-term (1991-2003) field site and river station data from the Little Vermilion River (LVR) watershed to evaluate performance of tile drainage routines in SWAT2009 revision 528 (the old routine) and SWAT2012 revisions 615 and 645 (the new routine). Both the old and new routines provided reasonable but unsatisfactory (NSE < 0.5) uncalibrated flow and nitrate loss results for a mildly sloped watershed with low runoff. The calibrated monthly tile flow, surface flow, nitrate-N in tile and surface flow, sediment and annual corn and soybean yield results from SWAT with the old and new tile drainage routines were compared with observed values. Generally, the new routine provided acceptable simulated tile flow (NSE = 0.48-0.65) and nitrate in tile flow (NSE = 0.48-0.68) for field sites with random pattern tile and constant tile spacing, while the old routine simulated tile flow and nitrate in tile flow results for the field site with constant tile spacing were unacceptable (NSE = 0.00-0.32 and -0.29-0.06, respectively). The new modified curve number calculation method in revision 645 (NSE = 0.50-0.81) better simulated surface runoff than revision 615 (NSE = -0.11-0.49). The calibration provided reasonable parameter sets for the old and new routines in the LVR watershed, and the validation results showed that the new routine has the potential to accurately simulate hydrologic processes in mildly sloped watersheds.

  4. Banks of lights dry tiles on Atlantis

    NASA Technical Reports Server (NTRS)

    2001-01-01

    KENNEDY SPACE CENTER, Fla. -- In the Orbiter Processing Facility, a worker points to some of the tiles on orbiter Atlantis that are being dried by clusters of 200-300 watt heat lamps. Significant rainstorms during the orbiter'''s turnaround for a ferry flight home from Edwards Air Force Base, Calif., caused a moisture problem. The tiles are part of the Thermal Protection System used on orbiters for extreme temperatures encountered during landing. Engineers are evaluating the current procedures to assure the tiles are in a safe and flight-ready condition.

  5. Structural tests on a tile/strain isolation pad thermal protection system. [space shuttles

    NASA Technical Reports Server (NTRS)

    Williams, J. G.

    1980-01-01

    The aluminum skin of the space shuttle is covered by a thermal protection system (TPS) consisting of a low density ceramic tile bonded to a matted-felt material called strain insulation pad (SIP). The structural characteristics of the TPS were studied experimentally under selected extreme load conditions. Three basic types of loads were imposed: tension, eccentrically applied tension, and combined in-plane force and transverse pressure. For some tests, transverse pressure was applied rapidly to simulate a transient shock wave passing over the tile. The failure mode for all specimens involved separation of the tile from the SIP at the silicone rubber bond interface. An eccentrically applied tension load caused the tile to separate from the SIP at loads lower than experienced at failure for pure tension loading. Moderate in-plane as well as shock loading did not cause a measurable reduction in the TPS ultimate failure strength. A strong coupling, however, was exhibited between in-plane and transverse loads and displacements.

  6. Nondestructive analysis and development

    NASA Technical Reports Server (NTRS)

    Moslehy, Faissal A.

    1993-01-01

    This final report summarizes the achievements of project #4 of the NASA/UCF Cooperative Agreement from January 1990 to December 1992. The objectives of this project are to review NASA's NDE program at Kennedy Space Center (KSC) and recommend means for enhancing the present testing capabilities through the use of improved or new technologies. During the period of the project, extensive development of a reliable nondestructive, non-contact vibration technique to determine and quantify the bond condition of the thermal protection system (TPS) tiles of the Space Shuttle Orbiter was undertaken. Experimental modal analysis (EMA) is used as a non-destructive technique for the evaluation of Space Shuttle thermal protection system (TPS) tile bond integrity. Finite element (FE) models for tile systems were developed and were used to generate their vibration characteristics (i.e. natural frequencies and mode shapes). Various TPS tile assembly configurations as well as different bond conditions were analyzed. Results of finite element analyses demonstrated a drop in natural frequencies and a change in mode shapes which correlate with both size and location of disbond. Results of experimental testing of tile panels correlated with FE results and demonstrated the feasibility of EMA as a viable technique for tile bond verification. Finally, testing performed on the Space Shuttle Columbia using a laser doppler velocimeter demonstrated the application of EMA, when combined with FE modeling, as a non-contact, non-destructive bond evaluation technique.

  7. Kinetics of DNA tile dimerization.

    PubMed

    Jiang, Shuoxing; Yan, Hao; Liu, Yan

    2014-06-24

    Investigating how individual molecular components interact with one another within DNA nanoarchitectures, both in terms of their spatial and temporal interactions, is fundamentally important for a better understanding of their physical behaviors. This will provide researchers with valuable insight for designing more complex higher-order structures that can be assembled more efficiently. In this report, we examined several spatial factors that affect the kinetics of bivalent, double-helical (DH) tile dimerization, including the orientation and number of sticky ends (SEs), the flexibility of the double helical domains, and the size of the tiles. The rate constants we obtained confirm our hypothesis that increased nucleation opportunities and well-aligned SEs accelerate tile-tile dimerization. Increased flexibility in the tiles causes slower dimerization rates, an effect that can be reversed by introducing restrictions to the tile flexibility. The higher dimerization rates of more rigid tiles results from the opposing effects of higher activation energies and higher pre-exponential factors from the Arrhenius equation, where the pre-exponential factor dominates. We believe that the results presented here will assist in improved implementation of DNA tile based algorithmic self-assembly, DNA based molecular robotics, and other specific nucleic acid systems, and will provide guidance to design and assembly processes to improve overall yield and efficiency.

  8. Small Group Dynamics in the Evolution of Global Network Terrorism: A Comprehensive, People-Based Approach. Part A: Select Publications

    DTIC Science & Technology

    2009-10-07

    uncontroversial that people can rank sacred values, and if sacred values can be ordered relative to each other they cannot be of infinite value. Emile ... Durkheim notes that a significant feature of religion is that it constitutes a system of beliefs and rites where "sacred tilings have relations of...coordination and subordination to one another" ( Durkheim . 1912/ 1995, p. 38). Indeed, in our own studies of religious and politically active samples of

  9. Terahertz NDE Application for Corrosion Detection and Evaluation under Shuttle Tiles

    NASA Technical Reports Server (NTRS)

    Anastasi, Robert F.; Madaras, Eric I.; Seebo, Jeffrey P.; Smith, Stephen W.; Lomness, Janice K.; Hintze, Paul E.; Kammerer, Catherine C.; Winfree, William P.; Russell, Richard W.

    2007-01-01

    Pulsed Terahertz NDE is being examined as a method to inspect for possible corrosion under Space Shuttle Tiles. Other methods such as ultrasonics, infrared, eddy current and microwave technologies have demonstrable shortcomings for tile NDE. This work applies Terahertz NDE, in the frequency range between 50 GHz and 1 THz, for the inspection of manufactured corrosion samples. The samples consist of induced corrosion spots that range in diameter (2.54 to 15.2 mm) and depth (0.036 to 0.787 mm) in an aluminum substrate material covered with tiles. Results of these measurements are presented for known corrosion flaws both covered and uncovered and for blind tests with unknown corrosion flaws covered with attached tiles. The Terahertz NDE system is shown to detect all artificially manufactured corrosion regions under a Shuttle tile with a depth greater than 0.13 mm.

  10. Atomic structure of a decagonal Al-Pd-Mn phase

    NASA Astrophysics Data System (ADS)

    Mihalkovič, Marek; Roth, Johannes; Trebin, Hans-Rainer

    2017-12-01

    We present a detailed structure solution for the 16 -Å decagonal quasicrystal in the Al-Pd-Mn system by means of cluster decoration and ab initio energy minimization. It is based on structure models of the ɛ and other approximant phases. The ɛ phases can be represented as subsets of a hexagon-boat-star (HBS) tiling. The decagonal phase comprises further HBS tiles. We have constructed several fictitious HBS approximants and optimized their structures individually. All tiles are decorated by two types of atomic clusters: the pseudo-Mackay icosahedron (PMI) and the large bicapped pentagonal prism (LBPP). It turns out that, whereas the PMI clusters can be kept essentially unchanged, the LBPP clusters must be adjusted in occupancy with Al atoms depending on their positions in the various tiles. In this way we obtain cluster decorations for all tiles of the decagonal quasicrystal. The calculations were confirmed by evaluation of an effective tile Hamiltonian.

  11. Tony Rollins prepares a new tile for the Space Shuttle orbiter

    NASA Technical Reports Server (NTRS)

    1998-01-01

    In the Tile Fabrication Shop, Tony Rollins, with United Space Alliance, cuts a High-Temperature Reusable Surface Insulation (HRSI) tile on a gun stock contour milling machine. About 70 percent of a Space Shuttle orbiter's external surface is shielded from heat by a network of more than 24,000 tiles formed from a silica fiber compound. HRSI tiles cover the lower surface of the orbiter, areas around the forward windows, upper body flap, the base heat shield, the 'eyeballs' on the front of the Orbital Maneuvering System (OMS) pods, and the leading and trailing edges of the vertical stabilizer and the rudder speed brake. They are generally 6 inches square, but may also be as large as 12 inches square in some areas, and 1 to 5 inches thick. More advanced materials such as Flexible Insulation Blankets have replaced tiles on some upper surfaces of the orbiter.

  12. Terahertz NDE application for corrosion detection and evaluation under Shuttle tiles

    NASA Astrophysics Data System (ADS)

    Anastasi, Robert F.; Madaras, Eric I.; Seebo, Jeffrey P.; Smith, Stephen W.; Lomness, Janice K.; Hintze, Paul E.; Kammerer, Catherine C.; Winfree, William P.; Russell, Richard W.

    2007-04-01

    Pulsed Terahertz NDE is being examined as a method to inspect for possible corrosion under Space Shuttle Tiles. Other methods such as ultrasonics, infrared, eddy current and microwave technologies have demonstrable shortcomings for tile NDE. This work applies Terahertz NDE, in the frequency range between 50 GHz and 1 THz, for the inspection of manufactured corrosion samples. The samples consist of induced corrosion spots that range in diameter (2.54 to 15.2 mm) and depth (0.036 to 0.787 mm) in an aluminum substrate material covered with tiles. Results of these measurements are presented for known corrosion flaws both covered and uncovered and for blind tests with unknown corrosion flaws covered with attached tiles. The Terahertz NDE system is shown to detect all artificially manufactured corrosion regions under a Shuttle tile with a depth greater than 0.13 mm.

  13. Thermal certification tests of Orbiter Thermal Protection System tiles coated with KSC coating slurries

    NASA Technical Reports Server (NTRS)

    Milhoan, James D.; Pham, Vuong T.; Sherborne, William D.

    1993-01-01

    Thermal tests of Orbiter thermal protection system (TPS) tiles, which were coated with borosilicate glass slurries fabricated at Kennedy Space Center (KSC), were performed in the Radiant Heat Test Facility and the Atmospheric Reentry Materials & Structures Evaluation Facility at Johnson Space Center to verify tile coating integrity after exposure to multiple entry simulation cycles in both radiant and convective heating environments. Eight high temperature reusable surface insulation (HRSI) tiles and six low temperature reusable surface insulation (LRSI) tiles were subjected to 25 cycles of radiant heat at peaked surface temperatures of 2300 F and 1200 F, respectively. For the LRSI tiles, an additional cycle at peaked surface temperature of 2100 F was performed. There was no coating crack on any of the HRSI specimens. However, there were eight small coating cracks (less than 2 inches long) on two of the six LRSI tiles on the 26th cycle. There was practically no change on the surface reflectivity, physical dimensions, or weight of any of the test specimens. There was no observable thermal-chemical degradation of the coating either. For the convective heat test, eight HRSI tiles were tested for five cycles at a surface temperature of 2300 F. There was no thermal-induced coating crack on any of the test specimens, almost no change on the surface reflectivity, and no observable thermal-chemical degradation with an exception of minor slumping of the coating under painted TPS identification numbers. The tests demonstrated that KSC's TPS slurries and coating processes meet the Orbiter's thermal specification requirements.

  14. Foam on Tile Impact Modeling for the STS-107 Investigation

    NASA Technical Reports Server (NTRS)

    Stellingwerf, R. F.; Robinson, J. H.; Richardson, S.; Evans, S. W.; Stallworth, R.; Hovater, M.

    2004-01-01

    Following the breakup of the Space Shuttle Columbia during reentry a NASA/Contractor investigation team was formed to examine the probable damage inflicted on Orbiter Thermal Protection System elements by impact of External Tank insulating foam projectiles. The authors formed a working subgroup within the larger team to apply the Smooth Particle Hydrodynamics code SPHC to the damage estimation problem. Numerical models of the Orbiter's tiles and of the Tank's foam were constructed and used as inputs into the code. Material properties needed to properly model the tiles and foam were obtained from other working subgroups who performed tests on these items for this purpose. Two- and three-dimensional models of the tiles were constructed, including the glass outer layer, the main body of LI-900 insulation, the densified lower layer of LI-900, the Nomex felt mounting layer, and the Aluminum 2024 vehicle skin. A model for the BX-250 foam including porous compression, elastic rebound, and surface erosion was developed. Code results for the tile damage and foam behavior were extensively validated through comparison with Southwest Research Institute foam-on-tile impact experiments carried out in 1999. These tests involved small projectiles striking individual tiles and small tile arrays. Following code and model validation we simulated impacts of larger foam projectiles on the examples of tile systems used on the Orbiter. Results for impacts on the main landing gear door are presented in this paper, including effects of impacts at several angles, and of rapidly rotating projectiles. General results suggest that foam impacts on tiles at about 500 mph could cause appreciable damage if the impact angle is greater than about 20 degrees. Some variations of the foam properties, such as increased brittleness or increased density could increase damage in some cases. Rotation up to 17 rps failed to increase the damage for the two cases considered. This does not rule out other cases in which the rotational energy might lead to an increase in tile damage, but suggests that in most cases rotation will not be an important factor.

  15. ATLAS Tile Calorimeter time calibration, monitoring and performance

    NASA Astrophysics Data System (ADS)

    Davidek, T.; ATLAS Collaboration

    2017-11-01

    The Tile Calorimeter (TileCal) is the hadronic calorimeter covering the central region of the ATLAS experiment at the LHC. This sampling device is made of plastic scintillating tiles alternated with iron plates and its response is calibrated to electromagnetic scale by means of several dedicated calibration systems. The accurate time calibration is important for the energy reconstruction, non-collision background removal as well as for specific physics analyses. The initial time calibration with so-called splash events and subsequent fine-tuning with collision data are presented. The monitoring of the time calibration with laser system and physics collision data is discussed as well as the corrections for sudden changes performed still before the recorded data are processed for physics analyses. Finally, the time resolution as measured with jets and isolated muons is presented.

  16. Hybrid Active-Passive Systems for Control of Aircraft Interior Noise

    NASA Technical Reports Server (NTRS)

    Fuller, Chris R.

    1999-01-01

    Previous work has demonstrated the large potential for hybrid active-passive systems for attenuating interior noise in aircraft fuselages. The main advantage of an active-passive system is, by utilizing the natural dynamics of the actuator system, the control actuator power and weight is markedly reduced and stability/robustness is enhanced. Three different active-passive approaches were studied in the past year. The first technique utilizes multiple tunable vibration absorbers (ATVA) for reducing narrow band sound radiated from panels and transmitted through fuselage structures. The focus is on reducing interior noise due to propeller or turbo fan harmonic excitation. Two types of tunable vibration absorbers were investigated; a solid state system based upon a piezoelectric mechanical exciter and an electromechanical system based upon a Motran shaker. Both of these systems utilize a mass-spring dynamic effect to maximize tile output force near resonance of the shaker system and so can also be used as vibration absorbers. The dynamic properties of the absorbers (i.e. resonance frequency) were modified using a feedback signal from an accelerometer mounted on the active mass, passed through a compensator and fed into the drive component of the shaker system (piezoelectric element or voice coil respectively). The feedback loop consisted of a two coefficient FIR filter, implemented on a DSP, where the input is acceleration of tile ATVA mass and the output is a force acting in parallel with the stiffness of the absorber. By separating the feedback signal into real and imaginary components, the effective natural frequency and damping of the ATVA can be altered independently. This approach gave control of the resonance frequencies while also allowing the simultaneous removal of damping from the ATVA, thus increasing the ease of controllability and effectiveness. In order to obtain a "tuned" vibration absorber the chosen resonant frequency was set to the excitation frequency. In order to minimize sound radiation a gradient descent algorithm was developed which globally adapted the resonance frequencies of multiple ATVA's while minimizing a cost based upon the radiated sound power or sound energy obtained from an array of microphones.

  17. Simulation of Foam Impact Effects on Components of the Space Shuttle Thermal Protection System. Chapter 7

    NASA Technical Reports Server (NTRS)

    Fahrenthold, Eric P.; Park, Young-Keun

    2004-01-01

    A series of three dimensional simulations has been performed to investigate analytically the effect of insulating foam impacts on ceramic tile and reinforced carbon-carbon components of the Space Shuttle thermal protection system. The simulations employed a hybrid particle-finite element method and a parallel code developed for use in spacecraft design applications. The conclusions suggested by the numerical study are in general consistent with experiment. The results emphasize the need for additional material testing work on the dynamic mechanical response of thermal protection system materials, and additional impact experiments for use in validating computational models of impact effects.

  18. SU-E-J-23: An Accurate Algorithm to Match Imperfectly Matched Images for Lung Tumor Detection Without Markers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rozario, T; Bereg, S; Chiu, T

    Purpose: In order to locate lung tumors on projection images without internal markers, digitally reconstructed radiograph (DRR) is created and compared with projection images. Since lung tumors always move and their locations change on projection images while they are static on DRRs, a special DRR (background DRR) is generated based on modified anatomy from which lung tumors are removed. In addition, global discrepancies exist between DRRs and projections due to their different image originations, scattering, and noises. This adversely affects comparison accuracy. A simple but efficient comparison algorithm is reported. Methods: This method divides global images into a matrix ofmore » small tiles and similarities will be evaluated by calculating normalized cross correlation (NCC) between corresponding tiles on projections and DRRs. The tile configuration (tile locations) will be automatically optimized to keep the tumor within a single tile which has bad matching with the corresponding DRR tile. A pixel based linear transformation will be determined by linear interpolations of tile transformation results obtained during tile matching. The DRR will be transformed to the projection image level and subtracted from it. The resulting subtracted image now contains only the tumor. A DRR of the tumor is registered to the subtracted image to locate the tumor. Results: This method has been successfully applied to kV fluoro images (about 1000 images) acquired on a Vero (Brainlab) for dynamic tumor tracking on phantom studies. Radiation opaque markers are implanted and used as ground truth for tumor positions. Although, other organs and bony structures introduce strong signals superimposed on tumors at some angles, this method accurately locates tumors on every projection over 12 gantry angles. The maximum error is less than 2.6 mm while the total average error is 1.0 mm. Conclusion: This algorithm is capable of detecting tumor without markers despite strong background signals.« less

  19. Tile drainage as karst: Conduit flow and diffuse flow in a tile-drained watershed

    USGS Publications Warehouse

    Schilling, K.E.; Helmers, M.

    2008-01-01

    The similarity of tiled-drained watersheds to karst drainage basins can be used to improve understanding of watershed-scale nutrient losses from subsurface tile drainage networks. In this study, short-term variations in discharge and chemistry were examined from a tile outlet collecting subsurface tile flow from a 963 ha agricultural watershed. Study objectives were to apply analytical techniques from karst springs to tile discharge to evaluate water sources and estimate the loads of agricultural pollutants discharged from the tile with conduit, intermediate and diffuse flow regimes. A two-member mixing model using nitrate, chloride and specific conductance was used to distinguish rainwater versus groundwater inputs. Results indicated that groundwater comprised 75% of the discharge for a three-day storm period and rainwater was primarily concentrated during the hydrograph peak. A contrasting pattern of solute concentrations and export loads was observed in tile flow. During base flow periods, tile flow consisted of diffuse flow from groundwater sources and contained elevated levels of nitrate, chloride and specific conductance. During storm events, suspended solids and pollutants adhered to soil surfaces (phosphorus, ammonium and organic nitrogen) were concentrated and discharged during the rapid, conduit flow portion of the hydrograph. During a three-day period, conduit flow occurred for 5.6% of the time but accounted for 16.5% of the total flow. Nitrate and chloride were delivered primarily with diffuse flow (more than 70%), whereas 80-94% of total suspended sediment, phosphorus and ammonium were exported with conduit and intermediate flow regimes. Understanding the water sources contributing to tile drainage and the manner by which pollutant discharge occurs from these systems (conduit, intermediate or diffuse flow) may be useful for designing, implementing and evaluating non-point source reduction strategies in tile-drained landscapes. ?? 2007 Elsevier B.V. All rights reserved.

  20. Phosphorus modeling in tile drained agricultural systems using APEX

    USDA-ARS?s Scientific Manuscript database

    Phosphorus losses through tile drained systems in agricultural landscapes may be causing the persistent eutrophication problems observed in surface water. The purpose of this paper is to evaluate the state of the science in the Agricultural Policy/Environmental eXtender (APEX) model related to surf...

  1. Association of pelvic fracture patterns, pelvic binder use and arterial angio-embolization with transfusion requirements and mortality rates; a 7-year retrospective cohort study.

    PubMed

    Agri, Fabio; Bourgeat, Mylène; Becce, Fabio; Moerenhout, Kevin; Pasquier, Mathieu; Borens, Olivier; Yersin, Bertrand; Demartines, Nicolas; Zingg, Tobias

    2017-11-09

    Pelvic fractures are severe injuries with frequently associated multi-system trauma and a high mortality rate. The value of the pelvic fracture pattern for predicting transfusion requirements and mortality is not entirely clear. To address hemorrhage from pelvic injuries, the early application of pelvic binders is now recommended and arterial angio-embolization is widely used for controlling arterial bleeding. Our aim was to assess the association of the pelvic fracture pattern according to the Tile classification system with transfusion requirements and mortality rates, and to evaluate the correlation between the use of pelvic binders and arterial angio-embolization and the mortality of patients with pelvic fractures. Single-center retrospective cohort study including all consecutive patients with a pelvic fracture from January 2008 to June 2015. All radiological fracture patterns were independently reviewed and grouped according to the Tile classification system. Data on patient demographics, use of pelvic binders and arterial angio-embolization, transfusion requirements and mortality were extracted from the institutional trauma registry and analyzed. The present study included 228 patients. Median patient age was 43.5 years and 68.9% were male. The two independent observers identified 105 Tile C (46.1%), 71 Tile B (31.1%) and 52 Tile A (22.8%) fractures, with substantial to almost perfect interobserver agreement (Kappa 0.70-0.83). Tile C fractures were associated with a higher mortality rate (p = 0.001) and higher transfusion requirements (p < 0.0001) than Tile A or B fractures. Arterial angio-embolization for pelvic bleeding (p = 0.05) and prehospital pelvic binder placement (p = 0.5) were not associated with differences in mortality rates. Tile C pelvic fractures are associated with higher transfusion requirements and a higher mortality rate than Tile A or B fractures. No association between the use of pelvic binders or arterial angio-embolization and survival was observed in this cohort of patients with pelvic fractures.

  2. Interobserver reliability of the young-burgess and tile classification systems for fractures of the pelvic ring.

    PubMed

    Koo, Henry; Leveridge, Mike; Thompson, Charles; Zdero, Rad; Bhandari, Mohit; Kreder, Hans J; Stephen, David; McKee, Michael D; Schemitsch, Emil H

    2008-07-01

    The purpose of this study was to measure interobserver reliability of 2 classification systems of pelvic ring fractures and to determine whether computed tomography (CT) improves reliability. The reliability of several radiographic findings was also tested. Thirty patients taken from a database at a Level I trauma facility were reviewed. For each patient, 3 radiographs (AP pelvis, inlet, and outlet) and CT scans were available. Six different reviewers (pelvic and acetabular specialist, orthopaedic traumatologist, or orthopaedic trainee) classified the injury according to Young-Burgess and Tile classification systems after reviewing plain radiographs and then after CT scans. The Kappa coefficient was used to determine interobserver reliability of these classification systems before and after CT scan. For plain radiographs, overall Kappa values for the Young-Burgess and Tile classification systems were 0.72 and 0.30, respectively. For CT scan and plain radiographs, the overall Kappa values for the Young-Burgess and Tile classification systems were 0.63 and 0.33, respectively. The pelvis/acetabular surgeons demonstrated the highest level of agreement using both classification systems. For individual questions, the addition of CT did significantly improve reviewer interpretation of fracture stability. The pre-CT and post-CT Kappa values for fracture stability were 0.59 and 0.93, respectively. The CT scan can improve the reliability of assessment of pelvic stability because of its ability to identify anatomical features of injury. The Young-Burgess system may be optimal for the learning surgeon. The Tile classification system is more beneficial for specialists in pelvic and acetabular surgery.

  3. Toward a molecular programming language for algorithmic self-assembly

    NASA Astrophysics Data System (ADS)

    Patitz, Matthew John

    Self-assembly is the process whereby relatively simple components autonomously combine to form more complex objects. Nature exhibits self-assembly to form everything from microscopic crystals to living cells to galaxies. With a desire to both form increasingly sophisticated products and to understand the basic components of living systems, scientists have developed and studied artificial self-assembling systems. One such framework is the Tile Assembly Model introduced by Erik Winfree in 1998. In this model, simple two-dimensional square 'tiles' are designed so that they self-assemble into desired shapes. The work in this thesis consists of a series of results which build toward the future goal of designing an abstracted, high-level programming language for designing the molecular components of self-assembling systems which can perform powerful computations and form into intricate structures. The first two sets of results demonstrate self-assembling systems which perform infinite series of computations that characterize computably enumerable and decidable languages, and exhibit tools for algorithmically generating the necessary sets of tiles. In the next chapter, methods for generating tile sets which self-assemble into complicated shapes, namely a class of discrete self-similar fractal structures, are presented. Next, a software package for graphically designing tile sets, simulating their self-assembly, and debugging designed systems is discussed. Finally, a high-level programming language which abstracts much of the complexity and tedium of designing such systems, while preventing many of the common errors, is presented. The summation of this body of work presents a broad coverage of the spectrum of desired outputs from artificial self-assembling systems and a progression in the sophistication of tools used to design them. By creating a broader and deeper set of modular tools for designing self-assembling systems, we hope to increase the complexity which is attainable. These tools provide a solid foundation for future work in both the Tile Assembly Model and explorations into more advanced models.

  4. RATT: RFID Assisted Tracking Tile. Preliminary results.

    PubMed

    Quinones, Dario R; Cuevas, Aaron; Cambra, Javier; Canals, Santiago; Moratal, David

    2017-07-01

    Behavior is one of the most important aspects of animal life. This behavior depends on the link between animals, their nervous systems and their environment. In order to study the behavior of laboratory animals several tools are needed, but a tracking tool is essential to perform a thorough behavioral study. Currently, several visual tracking tools are available. However, they have some drawbacks. For instance, when an animal is inside a cave, or is close to other animals, the tracking cameras cannot always detect the location or movement of this animal. This paper presents RFID Assisted Tracking Tile (RATT), a tracking system based on passive Radio Frequency Identification (RFID) technology in high frequency band according to ISO/IEC 15693. The RATT system is composed of electronic tiles that have nine active RFID antennas attached; in addition, it contains several overlapping passive coils to improve the magnetic field characteristics. Using several tiles, a large surface can be built on which the animals can move, allowing identification and tracking of their movements. This system, that could also be combined with a visual tracking system, paves the way for complete behavioral studies.

  5. Effects of thermal blooming on systems comprised of tiled subapertures

    NASA Astrophysics Data System (ADS)

    Leakeas, Charles L.; Bartell, Richard J.; Krizo, Matthew J.; Fiorino, Steven T.; Cusumano, Salvatore J.; Whiteley, Matthew R.

    2010-04-01

    Laser weapon systems comprise of tiled subapertures are rapidly emerging in the directed energy community. The Air Force Institute of Technology Center for Directed Energy (AFIT/CDE), under sponsorship of the HEL Joint Technology Office has developed performance models of such laser weapon system configurations consisting of tiled arrays of both slab and fiber subapertures. These performance models are based on results of detailed waveoptics analyses conducted using WaveTrain. Previous performance model versions developed in this effort represent system characteristics such as subaperture shape, aperture fill factor, subaperture intensity profile, subaperture placement in the primary aperture, subaperture mutual coherence (piston), subaperture differential jitter (tilt), and beam quality wave-front error associated with each subaperture. The current work is a prerequisite for the development of robust performance models for turbulence and thermal blooming effects for tiled systems. Emphasis is placed on low altitude tactical scenarios. The enhanced performance model developed will be added to AFIT/CDE's HELEEOS parametric one-on-one engagement level model via the Scaling for High Energy Laser and Relay Engagement (SHaRE) toolbox.

  6. State of science of phosphorus modeling in tile drained agricultural systems using APEX

    USDA-ARS?s Scientific Manuscript database

    Phosphorus losses through tile drained systems in agricultural landscapes may be causing the persistent eutrophication problems observed in surface water. The purpose of this paper is to evaluate the state of the science in the Agricultural Policy/Environmental eXtender (APEX) model related to surf...

  7. Tile-based self-assembly of a triple-helical polysaccharide into cell wall-like mesoporous nanocapsules.

    PubMed

    Wu, Chaoxi; Wang, Xiaoying; Wang, Jianjing; Zhang, Zhen; Wang, Zhiping; Wang, Yifei; Tang, Shunqing

    2017-07-20

    Tile-based self-assembly is a robust system in the construction of three-dimensional DNA nanostructures but it has been rarely applied to other helical biopolymers. β-Glucan is an immunoactive natural polymer which exists in a triple helical conformation. Herein, we report that β-glucan, after modification using two types of short chain acyl groups, can self-assemble into tiles with inactivated sticky ends at the interface of two solvents. These tiles consist of a single layer of helices laterally aligned, and the sticky ends can be activated when a few acyl groups at the ends are removed; these tiles can further pack into mesoporous nanocapsules, in a similar process as the sticky DNA tiles pack into complex polyhedral nano-objects. These nanocapsules were found to have targeted effects to antigen presenting cells in a RAW264.7 cell model. Our study suggests that tile-based self-assembly can be a general strategy for helical biopolymers, and on fully exploiting this strategy, various new functional nanostructures will become accessible in the future.

  8. A High-Resolution Tile-Based Approach for Classifying Biological Regions in Whole-Slide Histopathological Images

    PubMed Central

    Hoffman, R.A.; Kothari, S.; Phan, J.H.; Wang, M.D.

    2016-01-01

    Computational analysis of histopathological whole slide images (WSIs) has emerged as a potential means for improving cancer diagnosis and prognosis. However, an open issue relating to the automated processing of WSIs is the identification of biological regions such as tumor, stroma, and necrotic tissue on the slide. We develop a method for classifying WSI portions (512x512-pixel tiles) into biological regions by (1) extracting a set of 461 image features from each WSI tile, (2) optimizing tile-level prediction models using nested cross-validation on a small (600 tile) manually annotated tile-level training set, and (3) validating the models against a much larger (1.7x106 tile) data set for which ground truth was available on the whole-slide level. We calculated the predicted prevalence of each tissue region and compared this prevalence to the ground truth prevalence for each image in an independent validation set. Results show significant correlation between the predicted (using automated system) and reported biological region prevalences with p < 0.001 for eight of nine cases considered. PMID:27532012

  9. A High-Resolution Tile-Based Approach for Classifying Biological Regions in Whole-Slide Histopathological Images.

    PubMed

    Hoffman, R A; Kothari, S; Phan, J H; Wang, M D

    Computational analysis of histopathological whole slide images (WSIs) has emerged as a potential means for improving cancer diagnosis and prognosis. However, an open issue relating to the automated processing of WSIs is the identification of biological regions such as tumor, stroma, and necrotic tissue on the slide. We develop a method for classifying WSI portions (512x512-pixel tiles) into biological regions by (1) extracting a set of 461 image features from each WSI tile, (2) optimizing tile-level prediction models using nested cross-validation on a small (600 tile) manually annotated tile-level training set, and (3) validating the models against a much larger (1.7x10 6 tile) data set for which ground truth was available on the whole-slide level. We calculated the predicted prevalence of each tissue region and compared this prevalence to the ground truth prevalence for each image in an independent validation set. Results show significant correlation between the predicted (using automated system) and reported biological region prevalences with p < 0.001 for eight of nine cases considered.

  10. General view of the underside of the Orbiter Discovery on ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    General view of the underside of the Orbiter Discovery on the port side looking toward the starboard side and slightly forward. Note the landing gear assemblies, the jack stands attached to the External Tank (ET) attach points in on the Orbiter/ET propellant interface plate and the black High-Temperature Reusable Surface Insulation. The varying degrees of darkness of the tiles is due to the age of the tiles, the more recently replaced tiles are darker than the older tiles. The pattern created by the tile replacement is unique to each orbiter and becomes their "fingerprint". This view was taken in the Orbiter Processing Facility at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX

  11. Soil phosphorus loss in tile drainage water from long-term conventional- and non-tillage soils of Ontario with and without compost addition.

    PubMed

    Zhang, T Q; Tan, C S; Wang, Y T; Ma, B L; Welacky, T

    2017-02-15

    Recent ascertainment of tile drainage a predominant pathway of soil phosphorus (P) loss, along with the rise in concentration of soluble P in the Lake Erie, has led to a need to re-examine the impacts of agricultural practices. A three-year on-farm study was conducted to assess P loss in tile drainage water under long-term conventional- (CT) and non-tillage (NT) as influenced by yard waste leaf compost (LC) application in a Brookston clay loam soil. The effects of LC addition on soil P loss in tile drainage water varied depending on P forms and tillage systems. Under CT, dissolved reactive P (DRP) loss with LC addition over the study period was 765g P ha -1 , 2.9 times higher than CT without LC application, due to both a 50% increase in tile drainage flow volume and a 165% increase in DRP concentration. Under NT, DRP loss in tile drainage water with LC addition was 1447gPha -1 , 5.3 times greater than that for NT without LC application; this was solely caused by a 564% increase in DRP concentration. However, particulate P loads in tile drainage water with LC application remained unchanged, relative to non-LC application, regardless of tillage systems. Consequently, LC addition led to an increase in total P loads in tile drainage water by 57 and 69% under CT and NT, respectively. The results indicate that LC application may become an environmental concern due to increased DRP loss, particularly under NT. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

  12. Parametric Weight Comparison of Advanced Metallic, Ceramic Tile, and Ceramic Blanket Thermal Protection Systems

    NASA Technical Reports Server (NTRS)

    Myers, David E.; Martin, Carl J.; Blosser, Max L.

    2000-01-01

    A parametric weight assessment of advanced metallic panel, ceramic blanket, and ceramic tile thermal protection systems (TPS) was conducted using an implicit, one-dimensional (I-D) finite element sizing code. This sizing code contained models to account for coatings fasteners, adhesives, and strain isolation pads. Atmospheric entry heating profiles for two vehicles, the Access to Space (ATS) vehicle and a proposed Reusable Launch Vehicle (RLV), were used to ensure that the trends were not unique to a certain trajectory. Ten TPS concepts were compared for a range of applied heat loads and substructural heat capacities to identify general trends. This study found the blanket TPS concepts have the lightest weights over the majority of their applicable ranges, and current technology ceramic tiles and metallic TPS concepts have similar weights. A proposed, state-of-the-art metallic system which uses a higher temperature alloy and efficient multilayer insulation was predicted to be significantly lighter than the ceramic tile stems and approaches blanket TPS weights for higher integrated heat loads.

  13. A novel explicit approach to model bromide and pesticide transport in soils containing macropores

    NASA Astrophysics Data System (ADS)

    Klaus, J.; Zehe, E.

    2011-01-01

    The present study tests whether an explicit treatment of worm burrows is feasible for simulating water flow, bromide and pesticide transport in structured heterogeneous soils. The essence is to represent worm burrows as morphologically connected paths of low flow resistance in the spatially highly resolved model domain. A recent Monte Carlo study (Klaus and Zehe, 2010) revealed that this approach allowed successful reproduction of tile drain event discharge recorded during an irrigation experiment at a tile drained field site. However, several "hillslope architectures" that were all consistent with the available extensive data base allowed a good reproduction of tile drain flow response. Our second objective was thus to find out whether this "equifinality" in spatial model setups may be reduced when including bromide tracer data in the model falsification process. We thus simulated transport of bromide and Isoproturon (IPU) for the 13 spatial model setups, which performed best with respect to reproduce tile drain event discharge, without any further calibration. All model setups allowed a very good prediction of the temporal dynamics of cumulated bromide leaching into the tile drain, while only four of them matched the accumulated water balance and accumulated bromide loss into the tile drain. The number of behavioural model architectures could thus be reduced to four. One of those setups was used for simulating transport of IPU, using different parameter combinations to characterise adsorption according to the Footprint data base. Simulations could, however, only reproduce the observed leaching behaviour, when we allowed for retardation coefficients that were very close to one.

  14. Remote voice training: A case study on space shuttle applications, appendix C

    NASA Technical Reports Server (NTRS)

    Mollakarimi, Cindy; Hamid, Tamin

    1990-01-01

    The Tile Automation System includes applications of automation and robotics technology to all aspects of the Shuttle tile processing and inspection system. An integrated set of rapid prototyping testbeds was developed which include speech recognition and synthesis, laser imaging systems, distributed Ada programming environments, distributed relational data base architectures, distributed computer network architectures, multi-media workbenches, and human factors considerations. Remote voice training in the Tile Automation System is discussed. The user is prompted over a headset by synthesized speech for the training sequences. The voice recognition units and the voice output units are remote from the user and are connected by Ethernet to the main computer system. A supervisory channel is used to monitor the training sequences. Discussions include the training approaches as well as the human factors problems and solutions for this system utilizing remote training techniques.

  15. Kinetics of DNA Tile Dimerization

    PubMed Central

    2015-01-01

    Investigating how individual molecular components interact with one another within DNA nanoarchitectures, both in terms of their spatial and temporal interactions, is fundamentally important for a better understanding of their physical behaviors. This will provide researchers with valuable insight for designing more complex higher-order structures that can be assembled more efficiently. In this report, we examined several spatial factors that affect the kinetics of bivalent, double-helical (DH) tile dimerization, including the orientation and number of sticky ends (SEs), the flexibility of the double helical domains, and the size of the tiles. The rate constants we obtained confirm our hypothesis that increased nucleation opportunities and well-aligned SEs accelerate tile–tile dimerization. Increased flexibility in the tiles causes slower dimerization rates, an effect that can be reversed by introducing restrictions to the tile flexibility. The higher dimerization rates of more rigid tiles results from the opposing effects of higher activation energies and higher pre-exponential factors from the Arrhenius equation, where the pre-exponential factor dominates. We believe that the results presented here will assist in improved implementation of DNA tile based algorithmic self-assembly, DNA based molecular robotics, and other specific nucleic acid systems, and will provide guidance to design and assembly processes to improve overall yield and efficiency. PMID:24794259

  16. A landsat data tiling and compositing approach optimized for change detection in the conterminous United States

    USGS Publications Warehouse

    Nelson, Kurtis; Steinwand, Daniel R.

    2015-01-01

    Annual disturbance maps are produced by the LANDFIRE program across the conterminous United States (CONUS). Existing LANDFIRE disturbance data from 1999 to 2010 are available and current efforts will produce disturbance data through 2012. A tiling and compositing approach was developed to produce bi-annual images optimized for change detection. A tiled grid of 10,000 × 10,000 30 m pixels was defined for CONUS and adjusted to consolidate smaller tiles along national borders, resulting in 98 non-overlapping tiles. Data from Landsat-5,-7, and -8 were re-projected to the tile extents, masked to remove clouds, shadows, water, and snow/ice, then composited using a cosine similarity approach. The resultant images were used in a change detection algorithm to determine areas of vegetation change. This approach enabled more efficient processing compared to using single Landsat scenes, by taking advantage of overlap between adjacent paths, and allowed an automated system to be developed for the entire process.

  17. Electroless-plating technique for fabricating thin-wall convective heat-transfer models

    NASA Technical Reports Server (NTRS)

    Avery, D. E.; Ballard, G. K.; Wilson, M. L.

    1984-01-01

    A technique for fabricating uniform thin-wall metallic heat-transfer models and which simulates a Shuttle thermal protection system tile is described. Two 6- by 6- by 2.5-in. tiles were fabricated to obtain local heat transfer rates. The fabrication process is not limited to any particular geometry and results in a seamless thin-wall heat-transfer model which uses a one-wire thermocouple to obtain local cold-wall heat-transfer rates. The tile is relatively fragile because of the brittle nature of the material and the structural weakness of the flat-sided configuration; however, a method was developed and used for repairing a cracked tile.

  18. In Silico Design and Characterization of DNA Nanomaterials

    NASA Astrophysics Data System (ADS)

    Nash, Jessica A.

    Deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) function biologically as carriers of genetic information. However, due to their ability to self-assemble via base pairing, nucleic acid molecules have become widely used in nanotechnology. In this dissertation, in silico techniques are used to probe the structure-property relationships of nucleic acid based nanomaterials. In Part 1, computational methods are employed to formulate nanoparticle design rules for applications in nucleic acid packaging and delivery. Nanoparticles (NPs) play increasingly important roles in nanomedicine, where the surface chemistry allows for control over interactions with biomolecules. Understanding how DNA and RNA compaction occurs is relevant to biological systems and systems in nanotechnology, and critical for the development of more efficient and effective nanoparticle carriers. Computational modeling allows for the description of bio-nano systems and processes with unprecedented detail, and can provide insights and guidelines for the creation of new nanomaterials. Using all-atom molecular dynamics simulations, the effect of nanoparticle surface chemistry, size, and solvent ionic strength on interactions with DNA and RNA are reported. In Chapter 2, a systematic study of the effect of nanoparticle charge on ability to bend and wrap short sequences of DNA and RNA is presented. To cause bending of DNA, a nanoparticle charge of at least +30 is required. Higher nanoparticle charges cause a greater degree of compaction. For RNA, however, charged ligand end-groups bind internally and prevent RNA bending. Nanoparticles were designed to test the influence of NP ligand shell shape and length on RNA binding using these results. In Chapter 3, all-atom simulation of NPs with long double stranded RNA are reported. Simulations show that by shortening NP ligand length, double stranded RNA can be wrapped. In Chapter 4, we consider compaction of long DNA by nanoparticles. NPs with +120 charge can fully compact DNA, but the wrapping is unordered on the surface. Chapter 5 reports the influence of NPs on the structure of single stranded DNA and RNA, showing that NPs have a greater influence on poly-pyrimidine strands than poly-purine strands, and can interrupt hydrogen bonds and pi-pi stacking. In Part II of this dissertation, computational techniques are applied to study DNA tiles and origami. Due to base-pairing DNA can be used to place objects with nanoscale precision, with applications in nanoscience and nanomedicine. Chapter 6 presents the development of anticoagulants using DNA weave tiles and aptamers. More effective anticoagulants can be created by varying the DNA aptamer used, and increasing local concentration by attaching aptamers to a DNA tile. Molecular dynamics simulations show that increasing the number of helices on a DNA weave tile increases tile flexibility. Chapter 7 introduces a tool developed for visualization of DNA origami design. We develop circle map visualizations for DNA origami and maps of the base composition, allowing for visualizations of DNA origami that were not previously available. This tool is currently available online via nanohub (open source) for users around the world. The results reported here provide a fundamental understanding of the behavior of DNA systems in nanotechnology. Results are expected to aid in the development of more effective NP compaction agents, DNA delivery vehicles, and DNA origami design.

  19. System Integration Issues in Digital Photogrammetric Mapping

    DTIC Science & Technology

    1992-01-01

    elevation models, and/or rectified imagery/ orthophotos . Imagery exported from the DSPW can be either in a tiled image format or standard raster format...data. In the near future, correlation using "window shaping" operations along with an iterative orthophoto refinements methodology (Norvelle, 1992) is...components of TIES. The IDS passes tiled image data and ASCII header data to the DSPW. The tiled image file contains only image data. The ASCII header

  20. Laboratory evaluation to reduce respirable crystalline silica dust when cutting concrete roofing tiles using a masonry saw.

    PubMed

    Carlo, Rebecca V; Sheehy, John; Feng, H Amy; Sieber, William K

    2010-04-01

    Respirable crystalline silica dust exposure in residential roofers is a recognized hazard resulting from cutting concrete roofing tiles. Roofers cutting tiles using masonry saws can be exposed to high concentrations of respirable dust. Silica exposures remain a serious threat for nearly two million U.S. construction workers. Although it is well established that respiratory diseases associated with exposure to silica dust are preventable, they continue to occur and cause disability or death. The effectiveness of both a commercially available local exhaust ventilation (LEV) system and a water suppression system in reducing silica dust was evaluated separately. The LEV system exhausted 0.24, 0.13, or 0.12 m(3)/sec of dust laden air, while the water suppression system supplied 0.13, 0.06, 0.03, or 0.02 L/sec of water to the saw blade. Using a randomized block design, implemented under laboratory conditions, the aforementioned conditions were evaluated independently on two types of concrete roofing tiles (s-shape and flat) using the same saw and blade. Each engineering control (LEV or water suppression) was replicated eight times, or four times for each type of tile. Analysis of variance was performed by comparing the mean airborne respirable dust concentrations generated during each run and engineering control treatment. The use of water controls and ventilation controls compared with the "no control" treatment resulted in a statistically significant (p < 0.05) reduction of mean respirable dust concentrations generated per tile cut. The percent reduction for respirable dust concentrations was 99% for the water control and 91% for the LEV. Results suggest that water is an effective method for reducing crystalline silica exposures. However, water damage potential, surface discolorations, cleanup, slip hazards, and other requirements may make the use of water problematic in many situations. Concerns with implementing an LEV system to control silica dust exposures include sufficient capture velocity, additional weight of the saw with the LEV system, electricity connections, and cost of air handling unit.

  1. Logical NAND and NOR Operations Using Algorithmic Self-assembly of DNA Molecules

    NASA Astrophysics Data System (ADS)

    Wang, Yanfeng; Cui, Guangzhao; Zhang, Xuncai; Zheng, Yan

    DNA self-assembly is the most advanced and versatile system that has been experimentally demonstrated for programmable construction of patterned systems on the molecular scale. It has been demonstrated that the simple binary arithmetic and logical operations can be computed by the process of self assembly of DNA tiles. Here we report a one-dimensional algorithmic self-assembly of DNA triple-crossover molecules that can be used to execute five steps of a logical NAND and NOR operations on a string of binary bits. To achieve this, abstract tiles were translated into DNA tiles based on triple-crossover motifs. Serving as input for the computation, long single stranded DNA molecules were used to nucleate growth of tiles into algorithmic crystals. Our method shows that engineered DNA self-assembly can be treated as a bottom-up design techniques, and can be capable of designing DNA computer organization and architecture.

  2. Milestones Toward 50% Efficient Solar Cell Modules

    DTIC Science & Technology

    2007-09-01

    efficiency, both at solar cells and module level. The optical system consists of a tiled nonimaging concentrating system, coupled with a spectral...which combines a nonimaging optical concentrator (which does not require tracking and is called a static concentrator) with spectral splitting...DESIGN AND RESULTS The optical design is based on non-symmetric, nonimaging optics, tiled into an array. The central issues in the optical system

  3. Dynamic and programmable self-assembly of micro-rafts at the air-water interface

    PubMed Central

    Wang, Wendong; Giltinan, Joshua; Zakharchenko, Svetlana; Sitti, Metin

    2017-01-01

    Dynamic self-assembled material systems constantly consume energy to maintain their spatiotemporal structures and functions. Programmable self-assembly translates information from individual parts to the collective whole. Combining dynamic and programmable self-assembly in a single platform opens up the possibilities to investigate both types of self-assembly simultaneously and to explore their synergy. This task is challenging because of the difficulty in finding suitable interactions that are both dissipative and programmable. We present a dynamic and programmable self-assembling material system consisting of spinning at the air-water interface circular magnetic micro-rafts of radius 50 μm and with cosinusoidal edge-height profiles. The cosinusoidal edge-height profiles not only create a net dissipative capillary repulsion that is sustained by continuous torque input but also enable directional assembly of micro-rafts. We uncover the layered arrangement of micro-rafts in the patterns formed by dynamic self-assembly and offer mechanistic insights through a physical model and geometric analysis. Furthermore, we demonstrate programmable self-assembly and show that a 4-fold rotational symmetry encoded in individual micro-rafts translates into 90° bending angles and square-based tiling in the assembled structures of micro-rafts. We anticipate that our dynamic and programmable material system will serve as a model system for studying nonequilibrium dynamics and statistical mechanics in the future. PMID:28560332

  4. Dynamic and programmable self-assembly of micro-rafts at the air-water interface.

    PubMed

    Wang, Wendong; Giltinan, Joshua; Zakharchenko, Svetlana; Sitti, Metin

    2017-05-01

    Dynamic self-assembled material systems constantly consume energy to maintain their spatiotemporal structures and functions. Programmable self-assembly translates information from individual parts to the collective whole. Combining dynamic and programmable self-assembly in a single platform opens up the possibilities to investigate both types of self-assembly simultaneously and to explore their synergy. This task is challenging because of the difficulty in finding suitable interactions that are both dissipative and programmable. We present a dynamic and programmable self-assembling material system consisting of spinning at the air-water interface circular magnetic micro-rafts of radius 50 μm and with cosinusoidal edge-height profiles. The cosinusoidal edge-height profiles not only create a net dissipative capillary repulsion that is sustained by continuous torque input but also enable directional assembly of micro-rafts. We uncover the layered arrangement of micro-rafts in the patterns formed by dynamic self-assembly and offer mechanistic insights through a physical model and geometric analysis. Furthermore, we demonstrate programmable self-assembly and show that a 4-fold rotational symmetry encoded in individual micro-rafts translates into 90° bending angles and square-based tiling in the assembled structures of micro-rafts. We anticipate that our dynamic and programmable material system will serve as a model system for studying nonequilibrium dynamics and statistical mechanics in the future.

  5. Use of an engineering data management system in the analysis of space shuttle orbiter tiles

    NASA Technical Reports Server (NTRS)

    Giles, G. L.; Vallas, M.

    1981-01-01

    The use of an engineering data management system to facilitate the extensive stress analyses of the space shuttle orbiter thermal protection system is demonstrated. The methods used to gather, organize, and store the data; to query data interactively; to generate graphic displays of the data; and to access, transform, and prepare the data for input to a stress analysis program are described. Information related to many separate tiles can be accessed individually from the data base which has a natural organization from an engineering viewpoint. The flexible user features of the system facilitate changes in data content and organization which occur during the development and refinement of the tile analysis procedure. Additionally, the query language supports retrieval of data to satisfy a variety of user-specified conditions.

  6. A FORTRAN IV Computer Program for the Time Domain Analysis of the Two- Dimensional Dynamic Motions of General Buoy-Cable-Body Systems

    DTIC Science & Technology

    1977-06-01

    SPHEROIDAL BUOYS As mentioned previously, for the limiting case of zero ; educed frequency where tile free surface behaves as a rigid plane, the...4P ) -4 -4 ft O D - % Cdd :# P) fy ou Cd 1d Cd’. . 6 - C3 ’o .. eg S w Cd *g.4C~dI~**II~.a Ký 0 4 : 10 In H-C IV ..4 _ C) bu 0 40 la W C2C W cc lp lqa

  7. A Theoretical and Experimental Study of DNA Self-assembly

    NASA Astrophysics Data System (ADS)

    Chandran, Harish

    The control of matter and phenomena at the nanoscale is fast becoming one of the most important challenges of the 21st century with wide-ranging applications from energy and health care to computing and material science. Conventional top-down approaches to nanotechnology, having served us well for long, are reaching their inherent limitations. Meanwhile, bottom-up methods such as self-assembly are emerging as viable alternatives for nanoscale fabrication and manipulation. A particularly successful bottom up technique is DNA self-assembly where a set of carefully designed DNA strands form a nanoscale object as a consequence of specific, local interactions among the different components, without external direction. The final product of the self-assembly process might be a static nanostructure or a dynamic nanodevice that performs a specific function. Over the past two decades, DNA self-assembly has produced stunning nanoscale objects such as 2D and 3D lattices, polyhedra and addressable arbitrary shaped substrates, and a myriad of nanoscale devices such as molecular tweezers, computational circuits, biosensors and molecular assembly lines. In this dissertation we study multiple problems in the theory, simulations and experiments of DNA self-assembly. We extend the Turing-universal mathematical framework of self-assembly known as the Tile Assembly Model by incorporating randomization during the assembly process. This allows us to reduce the tile complexity of linear assemblies. We develop multiple techniques to build linear assemblies of expected length N using far fewer tile types than previously possible. We abstract the fundamental properties of DNA and develop a biochemical system, which we call meta-DNA, based entirely on strands of DNA as the only component molecule. We further develop various enzyme-free protocols to manipulate meta-DNA systems and provide strand level details along with abstract notations for these mechanisms. We simulate DNA circuits by providing detailed designs for local molecular computations that involve spatially contiguous molecules arranged on addressable substrates via enzyme-free DNA hybridization reaction cascades. We use the Visual DSD simulation software in conjunction with localized reaction rates obtained from biophysical modeling to create chemical reaction networks of localized hybridization circuits that are then model checked using the PRISM model checking software. We develop a DNA detection system employing the triggered self-assembly of a novel DNA dendritic nanostructure. Detection begins when a specific, single-stranded target DNA strand triggers a hybridization chain reaction between two distinct DNA hairpins. Each hairpin opens and hybridizes up to two copies of the other, and hence each layer of the growing dendritic nanostructure can in principle accommodate an exponentially increasing number of cognate molecules, generating a nanostructure with high molecular weight. We build linear activatable assemblies employing a novel protection/deprotection strategy to strictly enforce the direction of tiling assembly growth to ensure the robustness of the assembly process. Our system consists of two tiles that can form a linear co-polymer. These tiles, which are initially protected such that they do not react with each other, can be activated to form linear co-polymers via the use of a strand displacing enzyme.

  8. Measuring Fracture Times Of Ceramics

    NASA Technical Reports Server (NTRS)

    Shlichta, Paul J.; Bister, Leo; Bickler, Donald G.

    1989-01-01

    Electrical measurements complement or replace fast cinematography. Electronic system measures microsecond time intervals between impacts of projectiles on ceramic tiles and fracture tiles. Used in research on ceramics and ceramic-based composite materials such as armor. Hardness and low density of ceramics enable them to disintegrate projectiles more efficiently than metals. Projectile approaches ceramic tile specimen. Penetrating foil squares of triggering device activate display and recording instruments. As ceramic and resistive film break oscilloscope plots increase in electrical resistance of film.

  9. Terminating DNA Tile Assembly with Nanostructured Caps.

    PubMed

    Agrawal, Deepak K; Jiang, Ruoyu; Reinhart, Seth; Mohammed, Abdul M; Jorgenson, Tyler D; Schulman, Rebecca

    2017-10-24

    Precise control over the nucleation, growth, and termination of self-assembly processes is a fundamental tool for controlling product yield and assembly dynamics. Mechanisms for altering these processes programmatically could allow the use of simple components to self-assemble complex final products or to design processes allowing for dynamic assembly or reconfiguration. Here we use DNA tile self-assembly to develop general design principles for building complexes that can bind to a growing biomolecular assembly and terminate its growth by systematically characterizing how different DNA origami nanostructures interact with the growing ends of DNA tile nanotubes. We find that nanostructures that present binding interfaces for all of the binding sites on a growing facet can bind selectively to growing ends and stop growth when these interfaces are presented on either a rigid or floppy scaffold. In contrast, nucleation of nanotubes requires the presentation of binding sites in an arrangement that matches the shape of the structure's facet. As a result, it is possible to build nanostructures that can terminate the growth of existing nanotubes but cannot nucleate a new structure. The resulting design principles for constructing structures that direct nucleation and termination of the growth of one-dimensional nanostructures can also serve as a starting point for programmatically directing two- and three-dimensional crystallization processes using nanostructure design.

  10. Natural-color and color-infrared image mosaics of the Colorado River corridor in Arizona derived from the May 2009 airborne image collection

    USGS Publications Warehouse

    Davis, Philip A.

    2013-01-01

    The Grand Canyon Monitoring and Research Center (GCMRC) of the U.S. Geological Survey (USGS) periodically collects airborne image data for the Colorado River corridor within Arizona (fig. 1) to allow scientists to study the impacts of Glen Canyon Dam water release on the corridor’s natural and cultural resources. These data are collected from just above Glen Canyon Dam (in Lake Powell) down to the entrance of Lake Mead, for a total distance of 450 kilometers (km) and within a 500-meter (m) swath centered on the river’s mainstem and its seven main tributaries (fig. 1). The most recent airborne data collection in 2009 acquired image data in four wavelength bands (blue, green, red, and near infrared) at a spatial resolution of 20 centimeters (cm). The image collection used the latest model of the Leica ADS40 airborne digital sensor (the SH52), which uses a single optic for all four bands and collects and stores band radiance in 12-bits. Davis (2012) reported on the performance of the SH52 sensor and on the processing steps required to produce the nearly flawless four-band image mosaic (sectioned into map tiles) for the river corridor. The final image mosaic has a total of only 3 km of surface defects in addition to some areas of cloud shadow because of persistent inclement weather during data collection. The 2009 four-band image mosaic is perhaps the best image dataset that exists for the entire Arizona part of the Colorado River. Some analyses of these image mosaics do not require the full 12-bit dynamic range or all four bands of the calibrated image database, in which atmospheric scattering (or haze) had not been removed from the four bands. To provide scientists and the general public with image products that are more useful for visual interpretation, the 12-bit image data were converted to 8-bit natural-color and color-infrared images, which also removed atmospheric scattering within each wavelength-band image. The conversion required an evaluation of the histograms of each band’s digital-number population within each map tile throughout the corridor and the determination of the digital numbers corresponding to the lower and upper one percent of the picture-element population within each map tile. Visual examination of the image tiles that were given a 1-percent stretch (whereby the lower 1- percent 12-bit digital number is assigned an 8-bit value of zero and the upper 1-percent 12-bit digital number is assigned an 8-bit value of 255) indicated that this stretch sufficiently removed atmospheric scattering, which provided improved image clarity and true natural colors for all surface materials. The lower and upper 1-percent, 12-bit digital numbers for each wavelength-band image in the image tiles exhibit erratic variations along the river corridor; the variations exhibited similar trends in both the lower and upper 1-percent digital numbers for all four wavelength-band images (figs. 2–5). The erratic variations are attributed to (1) daily variations in atmospheric water-vapor content due to monsoonal storms, (2) variations in channel water color due to variable sediment input from tributaries, and (3) variations in the amount of topographic shadows within each image tile, in which reflectance is dominated by atmospheric scattering. To make the surface colors of the stretched, 8-bit images consistent among adjacent image tiles, it was necessary to average both the lower and upper 1-percent digital values for each wavelength-band image over 20 river miles to subdue the erratic variations. The average lower and upper 1-percent digital numbers for each image tile (figs. 2–5) were used to convert the 12-bit image values to 8-bit values and the resulting 8-bit four-band images were stored as natural-color (red, green, and blue wavelength bands) and color-infrared (near-infrared, red, and green wavelength bands) images in embedded geotiff format, which can be read and used by most geographic information system (GIS) and image-processing software. The tiff world files (tfw) are provided, even though they are generally not needed for most software to read an embedded geotiff image. All image data are projected in the State Plane (SP) map projection using the central Arizona zone (202) and the North American Datum of 1983 (NAD83). The map-tile scheme used to segment the corridor image mosaic followed the standard USGS quarter-quadrangle (QQ) map borders, but the high resolution (20 cm) of the images required further quarter segmentation (QQQ) of the standard QQ tiles, where the image mosaic covered a large fraction of a QQ map tile (segmentation shown in (figure 6), where QQ_1 to QQ_4 shows the number convention used to designate a quarter of a QQ tile). To minimize the size of each image tile, each image or map tile was subset to only include that part of the tile that had image data. In addition, some QQQ image tiles within a QQ tile were combined when adjacent QQQ map tiles were small. Thus, some image tiles consist of combinations of QQQ map tiles, some consist of an entire QQ map tile, and some consist of two adjoining QQ map tiles. The final image tiles number 143, which is a large number of files to list on the Internet for both the natural-color and color-infrared images. Thus, the image tiles were placed in seven file folders based on the one-half-degree geographic boundaries within the study area (fig. 7). The map tiles in each file folder were compressed to minimize folder size for more efficient downloading. The file folders are sequentially referred to as zone 1 through zone 7, proceeding down river (fig. 7). The QQ designations of the image tiles contained within each folder or zone are shown on the index map for each respective zone (figs. 8–14).

  11. [Decision process of Notification Value by the Dose Index Registry system in X-ray computed tomography].

    PubMed

    Shinozaki, Masafumi; Muramatsu, Yoshihisa; Sasaki, Toru

    2014-01-01

    A new technical standard for X-ray computed tomography (CT) has been published by the National Electrical Manufacturers Association (NEMA) that allows the Alert Value and Notification Value for cumulative dose to be configurable by CT systems operators in conjunction with the XR-25 (Dose check) standard. In this study, a decision method of the Notification Values for reducing the radiation dose was examined using the dose index registry (DIR) system, during 122 continuous days from August 1, 2012 to November 30, 2012. CT images were obtained using the Discovery CT 750HD (GE Healthcare) and the dose index was calculated using the DoseWatch DIR system. The CT dose index-volume (CTDIvol) and dose-length product (DLP) were output from the DIR system in comma-separated value (CSV) file format for each examination protocol. All data were shown as a schematic boxplot using statistical processing software. The CTDIvol of a routine chest examination showed the following values (maximum: 23.84 mGy; minimum: 2.55 mGy; median: 7.60 mGy; 75% tile: 10.01 mGy; 25% tile: 6.54 mGy). DLP showed the following values (maximum: 944.56 mGy·cm; minimum: 97.25 mGy·cm; median: 307.35 mGy·cm; 75% tile: 406.87 mGy·cm; 25% tile: 255.75 mGy·cm). These results indicate that the 75% tile of CTDIvol and DLP as an initial value proved to be safe and efficient for CT examination and operation. We have thus established one way of determining the Notification Value from the output of the DIR system. Transfer back to the protocol of the CT and automated processing each numeric value in the DIR system is desired.

  12. Gap heating with pressure gradients. [for Shuttle Orbiter thermal protection system tiles

    NASA Technical Reports Server (NTRS)

    Scott, C. D.; Maraia, R. J.

    1979-01-01

    The heating rate distribution and temperature response on the gap walls of insulating tiles is analyzed to determine significant phenomena and parameters in flows where there is an external surface pressure gradient. Convective heating due to gap flow, modeled as fully developed pipe flow, is coupled with a two-dimensional thermal model of the tiles that includes conduction and radiative heat transfer. To account for geometry and important environmental parameters, scale factors are obtained by curve-fitting measured temperatures to analytical solutions. These scale factors are then used to predict the time-dependent gap heat flux and temperature response of tile gaps on the Space Shuttle Orbiter during entry.

  13. Programmed coherent coupling in a synthetic DNA-based excitonic circuit

    NASA Astrophysics Data System (ADS)

    Boulais, Étienne; Sawaya, Nicolas P. D.; Veneziano, Rémi; Andreoni, Alessio; Banal, James L.; Kondo, Toru; Mandal, Sarthak; Lin, Su; Schlau-Cohen, Gabriela S.; Woodbury, Neal W.; Yan, Hao; Aspuru-Guzik, Alán; Bathe, Mark

    2018-02-01

    Natural light-harvesting systems spatially organize densely packed chromophore aggregates using rigid protein scaffolds to achieve highly efficient, directed energy transfer. Here, we report a synthetic strategy using rigid DNA scaffolds to similarly program the spatial organization of densely packed, discrete clusters of cyanine dye aggregates with tunable absorption spectra and strongly coupled exciton dynamics present in natural light-harvesting systems. We first characterize the range of dye-aggregate sizes that can be templated spatially by A-tracts of B-form DNA while retaining coherent energy transfer. We then use structure-based modelling and quantum dynamics to guide the rational design of higher-order synthetic circuits consisting of multiple discrete dye aggregates within a DX-tile. These programmed circuits exhibit excitonic transport properties with prominent circular dichroism, superradiance, and fast delocalized exciton transfer, consistent with our quantum dynamics predictions. This bottom-up strategy offers a versatile approach to the rational design of strongly coupled excitonic circuits using spatially organized dye aggregates for use in coherent nanoscale energy transport, artificial light-harvesting, and nanophotonics.

  14. KSC-98pc930

    NASA Image and Video Library

    1998-08-10

    In the Tile Fabrication Shop, Tony Rollins, with United Space Alliance, cuts a High-Temperature Reusable Surface Insulation (HRSI) tile on a gun stock contour milling machine. About 70 percent of a Space Shuttle orbiter’s external surface is shielded from heat by a network of more than 24,000 tiles formed from a silica fiber compound. HRSI tiles cover the lower surface of the orbiter, areas around the forward windows, upper body flap, the base heat shield, the "eyeballs" on the front of the Orbital Maneuvering System (OMS) pods, and the leading and trailing edges of the vertical stabilizer and the rudder speed brake. They are generally 6 inches square, but may also be as large as 12 inches square in some areas, and 1 to 5 inches thick. More advanced materials such as Flexible Insulation Blankets have replaced tiles on some upper surfaces of the orbiter

  15. Parallel tiled Nussinov RNA folding loop nest generated using both dependence graph transitive closure and loop skewing.

    PubMed

    Palkowski, Marek; Bielecki, Wlodzimierz

    2017-06-02

    RNA secondary structure prediction is a compute intensive task that lies at the core of several search algorithms in bioinformatics. Fortunately, the RNA folding approaches, such as the Nussinov base pair maximization, involve mathematical operations over affine control loops whose iteration space can be represented by the polyhedral model. Polyhedral compilation techniques have proven to be a powerful tool for optimization of dense array codes. However, classical affine loop nest transformations used with these techniques do not optimize effectively codes of dynamic programming of RNA structure predictions. The purpose of this paper is to present a novel approach allowing for generation of a parallel tiled Nussinov RNA loop nest exposing significantly higher performance than that of known related code. This effect is achieved due to improving code locality and calculation parallelization. In order to improve code locality, we apply our previously published technique of automatic loop nest tiling to all the three loops of the Nussinov loop nest. This approach first forms original rectangular 3D tiles and then corrects them to establish their validity by means of applying the transitive closure of a dependence graph. To produce parallel code, we apply the loop skewing technique to a tiled Nussinov loop nest. The technique is implemented as a part of the publicly available polyhedral source-to-source TRACO compiler. Generated code was run on modern Intel multi-core processors and coprocessors. We present the speed-up factor of generated Nussinov RNA parallel code and demonstrate that it is considerably faster than related codes in which only the two outer loops of the Nussinov loop nest are tiled.

  16. Dscam2 mediates axonal tiling in the Drosophila visual system

    PubMed Central

    Millard, S. Sean; Flanagan, John J.; Pappu, Kartik S.; Wu, Wei; Zipursky, S. Lawrence

    2009-01-01

    Sensory processing centres in both the vertebrate and the invertebrate brain are often organized into reiterated columns, thus facilitating an internal topographic representation of the external world. Cells within each column are arranged in a stereotyped fashion and form precise patterns of synaptic connections within discrete layers. These connections are largely confined to a single column, thereby preserving the spatial information from the periphery. Other neurons integrate this information by connecting to multiple columns. Restricting axons to columns is conceptually similar to tiling. Axons and dendrites of neighbouring neurons of the same class use tiling to form complete, yet non-overlapping, receptive fields1-3. It is thought that, at the molecular level, cell-surface proteins mediate tiling through contact-dependent repulsive interactions1,2,4,5, but proteins serving this function have not yet been identified. Here we show that the immunoglobulin superfamily member Dscam2 restricts the connections formed by L1 lamina neurons to columns in the Drosophila visual system. Our data support a model in which Dscam2 homophilic interactions mediate repulsion between neurites of L1 cells in neighbouring columns. We propose that Dscam2 is a tiling receptor for L1 neurons. PMID:17554308

  17. Comparison of export dynamics of nutrients and animal-borne estrogens from a tile-drained Midwestern agroecosystem.

    PubMed

    Gall, Heather E; Sassman, Stephen A; Jenkinson, Byron; Lee, Linda S; Jafvert, Chad T

    2015-04-01

    Concentrated animal feeding operations (CAFOs) are known to be a source of nutrients and hormones found in surface water bodies around the world. While the fate and transport of nutrients have been studied for decades, much less research has been conducted on the fate and transport of hormones. To facilitate a comparison of nutrient and hormone export dynamics from farm fields, nitrate + nitrite (N), dissolved reactive phosphorus (DRP), 17α- and 17β-estradiol (E2), estrone (E1), and estriol (E3) were monitored in a tile drain and receiving ditch for one year on a working farm in north central Indiana. Repeated animal waste applications led to high frequency detection of hormones (>50% in tile drain; >90% in the ditch) and nutrients (>70% for DRP; 100% for N). Hydrologic variability was found to be a dominant factor controlling export of N, DRP, and E1 to the drain and ditch. Of the estrogens, the temporal trend in E1 export was most similar to that of DRP. Differences in temporal export between P and the other estrogens likely were due to differences in the biogeochemical processes that affect their fate and transport within the agroecosystem. During short periods when the flowrate exceeded the 80(th) percentile for the year, over 70% of the total mass export of DRP and E1 occurred for the year in both the tile drain and ditch, demonstrating the importance of high-flow events. Therefore, best management practices must be effective during large flow events to substantially reduce transport to downstream locations. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. KSC-01pp1023

    NASA Image and Video Library

    2001-05-24

    KENNEDY SPACE CENTER, FLA. -- In the Orbiter Processing Facility, a worker points to some of the tiles on orbiter Atlantis that are being dried by clusters of 200-300 watt heat lamps. Significant rainstorms during the orbiter’s turnaround for a ferry flight home from Edwards Air Force Base, Calif., caused a moisture problem. The tiles are part of the Thermal Protection System used on orbiters for extreme temperatures encountered during landing. Engineers are evaluating the current procedures to assure the tiles are in a safe and flight-ready condition

  19. KSC-01PP1024

    NASA Image and Video Library

    2001-05-24

    KENNEDY SPACE CENTER, FLA. -- In the Orbiter Processing Facility, a worker points to some of the tiles on orbiter Atlantis that are being dried by clusters of 200-300 watt heat lamps. Significant rainstorms during the orbiter’s turnaround for a ferry flight home from Edwards Air Force Base, Calif., caused a moisture problem. The tiles are part of the Thermal Protection System used on orbiters for extreme temperatures encountered during landing. Engineers are evaluating the current procedures to assure the tiles are in a safe and flight-ready condition

  20. KSC-2012-1587

    NASA Image and Video Library

    2012-03-01

    CAPE CANAVERAL, Fla. -- The heat shield tiles that will be installed to the backshell of the Orion Multi-Purpose Crew Vehicle's Exploration Flight Test EFT-1 capsule are removed from a Keith thermal automation oven. Inside, the tiles were baked at 2,200 degrees F to cure their ceramic coating. The work to manufacture and inspect the tiles is taking place in Kennedy's Thermal Protection System Facility. EFT-1 will be used during Orion's first test flight in space. For more information, visit www.nasa.gov/orion. Photo credit: Frankie Martin

  1. KSC-2012-1572

    NASA Image and Video Library

    2012-03-01

    Tim Wright, a United Space Alliance engineering manager at NASA's Kennedy Space Center in Florida, unpacks the heat shield tiles that will be installed to the backshell of the Orion Multi-Purpose Crew Vehicle's Exploration Flight Test EFT-1 capsule. The tiles are being manufactured and inspected in Kennedy's Thermal Protection System Facility. The tiles will be baked at 2,200 degrees F to cure their ceramic coating. EFT-1 will be used during Orion's first test flight in space. For more information, visit www.nasa.gov/orion. Photo credit: Frankie Martin

  2. Tile survey seen during EVA 3

    NASA Image and Video Library

    2005-08-03

    S114-E-6388 (3 August 2005) --- A close-up view of a portion of the thermal protection tiles on Space Shuttle Discovery’s underside is featured in this image photographed by astronaut Stephen K. Robinson, STS-114 mission specialist, during the mission’s third session of extravehicular activities (EVA). Robinson’s shadow is visible on the thermal protection tiles and a portion of the Canadian-built remote manipulator system (RMS) robotic arm and the Nile River is visible at bottom.

  3. Contributions of systematic tile drainage to watershed-scale phosphorus transport.

    PubMed

    King, Kevin W; Williams, Mark R; Fausey, Norman R

    2015-03-01

    Phosphorus (P) transport from agricultural fields continues to be a focal point for addressing harmful algal blooms and nuisance algae in freshwater systems throughout the world. In humid, poorly drained regions, attention has turned to P delivery through subsurface tile drainage. However, research on the contributions of tile drainage to watershed-scale P losses is limited. The objective of this study was to evaluate long-term P movement through tile drainage and its manifestation at the watershed outlet. Discharge data and associated P concentrations were collected for 8 yr (2005-2012) from six tile drains and from the watershed outlet of a headwater watershed within the Upper Big Walnut Creek watershed in central Ohio. Results showed that tile drainage accounted for 47% of the discharge, 48% of the dissolved P, and 40% of the total P exported from the watershed. Average annual total P loss from the watershed was 0.98 kg ha, and annual total P loss from the six tile drains was 0.48 kg ha. Phosphorus loads in tile and watershed discharge tended to be greater in the winter, spring, and fall, whereas P concentrations were greatest in the summer. Over the 8-yr study, P transported in tile drains represented <2% of typical application rates in this watershed, but >90% of all measured concentrations exceeded recommended levels (0.03 mg L) for minimizing harmful algal blooms and nuisance algae. Thus, the results of this study show that in systematically tile-drained headwater watersheds, the amount of P delivered to surface waters via tile drains cannot be dismissed. Given the amount of P loss relative to typical application rates, development and implementation of best management practices (BMPs) must jointly consider economic and environmental benefits. Specifically, implementation of BMPs should focus on late fall, winter, and early spring seasons when most P loading occurs. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  4. Tiled architecture of a CNN-mostly IP system

    NASA Astrophysics Data System (ADS)

    Spaanenburg, Lambert; Malki, Suleyman

    2009-05-01

    Multi-core architectures have been popularized with the advent of the IBM CELL. On a finer grain the problems in scheduling multi-cores have already existed in the tiled architectures, such as the EPIC and Da Vinci. It is not easy to evaluate the performance of a schedule on such architecture as historical data are not available. One solution is to compile algorithms for which an optimal schedule is known by analysis. A typical example is an algorithm that is already defined in terms of many collaborating simple nodes, such as a Cellular Neural Network (CNN). A simple node with a local register stack together with a 'rotating wheel' internal communication mechanism has been proposed. Though the basic CNN allows for a tiled implementation of a tiled algorithm on a tiled structure, a practical CNN system will have to disturb this regularity by the additional need for arithmetical and logical operations. Arithmetic operations are needed for instance to accommodate for low-level image processing, while logical operations are needed to fork and merge different data streams without use of the external memory. It is found that the 'rotating wheel' internal communication mechanism still handles such mechanisms without the need for global control. Overall the CNN system provides for a practical network size as implemented on a FPGA, can be easily used as embedded IP and provides a clear benchmark for a multi-core compiler.

  5. Reducing nitrate loss in tile drainage water with cover crops and water-table management systems.

    PubMed

    Drury, C F; Tan, C S; Welacky, T W; Reynolds, W D; Zhang, T Q; Oloya, T O; McLaughlin, N B; Gaynor, J D

    2014-03-01

    Nitrate lost from agricultural soils is an economic cost to producers, an environmental concern when it enters rivers and lakes, and a health risk when it enters wells and aquifers used for drinking water. Planting a winter wheat cover crop (CC) and/or use of controlled tile drainage-subirrigation (CDS) may reduce losses of nitrate (NO) relative to no cover crop (NCC) and/or traditional unrestricted tile drainage (UTD). A 6-yr (1999-2005) corn-soybean study was conducted to determine the effectiveness of CC+CDS, CC+UTD, NCC+CDS, and NCC+UTD treatments for reducing NO loss. Flow volume and NO concentration in surface runoff and tile drainage were measured continuously, and CC reduced the 5-yr flow-weighted mean (FWM) NO concentration in tile drainage water by 21 to 38% and cumulative NO loss by 14 to 16% relative to NCC. Controlled tile drainage-subirrigation reduced FWM NO concentration by 15 to 33% and cumulative NO loss by 38 to 39% relative to UTD. When CC and CDS were combined, 5-yr cumulative FWM NO concentrations and loss in tile drainage were decreased by 47% (from 9.45 to 4.99 mg N L and from 102 to 53.6 kg N ha) relative to NCC+UTD. The reductions in runoff and concomitant increases in tile drainage under CC occurred primarily because of increases in near-surface soil hydraulic conductivity. Cover crops increased corn grain yields by 4 to 7% in 2004 increased 3-yr average soybean yields by 8 to 15%, whereas CDS did not affect corn or soybean yields over the 6 yr. The combined use of a cover crop and water-table management system was highly effective for reducing NO loss from cool, humid agricultural soils. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  6. Adhesives for bonding RSI tile to GrPI structure for advanced space transportation systems

    NASA Technical Reports Server (NTRS)

    Smith, K. E.; Hamermesh, C. L.; Hogenson, P. A.

    1979-01-01

    A system was developed for bonding RSI tiles to a graphite/polymide composite substrate which would withstand the full range of environmental conditions. The bonding system, designated RA59, consists of a mixture of glass (sesquisiloxane) resin in RTV 560 silicone. A significant number of data points for the RA59 are in the 65-psi failure range both when tested, and after exposure to 700 F. This is over two times the best shear and tensile values obtained with RV60 at this temperature. It is concluded that with a thorough understanding of the critical parameters involved, the higher values should be obtained consistently with the RA59. This is of particular significance if higher strength tiles were to be used in a hard-bonded configuration.

  7. The Laser calibration of the ATLAS Tile Calorimeter during the LHC run 1

    DOE PAGES

    Abdallah, J.; Alexa, C.; Coutinho, Y. Amaral; ...

    2016-10-12

    This article describes the Laser calibration system of the ATLAS hadronic Tile Calorimeter that has been used during the run 1 of the LHC . First, the stability of the system associated readout electronics is studied. It is found to be stable with variations smaller than 0.6 %. Then, the method developed to compute the calibration constants, to correct for the variations of the gain of the calorimeter photomultipliers, is described. These constants were determined with a statistical uncertainty of 0.3 % and a systematic uncertainty of 0.2 % for the central part of the calorimeter and 0.5 % formore » the end-caps. Lastly, the detection and correction of timing mis-configuration of the Tile Calorimeter using the Laser system are also presented.« less

  8. The Laser calibration of the ATLAS Tile Calorimeter during the LHC run 1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Abdallah, J.; Alexa, C.; Coutinho, Y. Amaral

    This article describes the Laser calibration system of the ATLAS hadronic Tile Calorimeter that has been used during the run 1 of the LHC . First, the stability of the system associated readout electronics is studied. It is found to be stable with variations smaller than 0.6 %. Then, the method developed to compute the calibration constants, to correct for the variations of the gain of the calorimeter photomultipliers, is described. These constants were determined with a statistical uncertainty of 0.3 % and a systematic uncertainty of 0.2 % for the central part of the calorimeter and 0.5 % formore » the end-caps. Lastly, the detection and correction of timing mis-configuration of the Tile Calorimeter using the Laser system are also presented.« less

  9. Impact of tile drainage on evapotranspiration in South Dakota, USA, based on high spatiotemporal resolution evapotranspiration time series from a multi-satellite data fusion system

    USGS Publications Warehouse

    Yang, Yun; Anderson, Martha C.; Gao, Feng; Hain, Christopher; Kustas, William P.; Meyers, Tilden P.; Crow, Wade; Finocchiaro, Raymond G.; Otkin, Jason; Sun, Liang; Yang, Yang

    2017-01-01

    Soil drainage is a widely used agricultural practice in the midwest USA to remove excess soil water to potentially improve the crop yield. Research shows an increasing trend in baseflow and streamflow in the midwest over the last 60 years, which may be related to artificial drainage. Subsurface drainage (i.e., tile) in particular may have strongly contributed to the increase in these flows, because of its extensive use and recent gain in the popularity as a yield-enhancement practice. However, how evapotranspiration (ET) is impacted by tile drainage on a regional level is not well-documented. To explore spatial and temporal ET patterns and their relationship to tile drainage, we applied an energy balance-based multisensor data fusion method to estimate daily 30-m ET over an intensively tile-drained area in South Dakota, USA, from 2005 to 2013. Results suggest that tile drainage slightly decreases the annual cumulative ET, particularly during the early growing season. However, higher mid-season crop water use suppresses the extent of the decrease of the annual cumulative ET that might be anticipated from widespread drainage. The regional water balance analysis during the growing season demonstrates good closure, with the average residual from 2005 to 2012 as low as -3 mm. As an independent check of the simulated ET at the regional scale, the water balance analysis lends additional confidence to the study. The results of this study improve our understanding of the influence of agricultural drainage practices on regional ET, and can affect future decision making regarding tile drainage systems.

  10. Lactose-modified DNA tile nanostructures as drug carriers.

    PubMed

    Akkus Sut, Pinar; Tunc, Cansu Umran; Culha, Mustafa

    2016-09-01

    DNA hybridization allows the preparation of nanoscale DNA structures with desired shape and size. DNA structures using simple base pairing can be used for the delivery of drug molecules into the cells. Since DNA carries multiple negative charges, their cellular uptake efficiency is low. Thus, the modification of the DNA structures with molecules that may enhance the cellular internalization may be an option. The objective of this study is to construct DNA-based nanocarrier system and to investigate the cellular uptake of DNA tile with/without lactose modification. Doxorubicin was intercalated to DNA tile and cellular uptake of drug-loaded DNA-based carrier with/without lactose modification was investigated in vitro. HeLa, BT-474, and MDA-MB-231 cancer cells were used for cellular uptake studies and cytotoxicity assays. Using fluorescence spectroscopy, flow cytometry, and confocal microscopy, cellular uptake behavior of DNA tile was investigated. The cytotoxicity of DNA tile structures was determined with WST-1 assay. The results show that modification with lactose effectively increases the intracellular uptake of doxorubicin loaded DNA tile structure by cancer cells compared with the unmodified DNA tile. The findings of this study suggest that DNA-based nanostructures modified with carbohydrates can be used as suitable multifunctional nanocarriers with simple chemical modifications.

  11. Shuttle Upgrade Program: Tile TPS

    NASA Technical Reports Server (NTRS)

    Leiser, Daniel B.; Stewart, David A.; DiFiore, Robert; Irby, Ed; Arnold, James (Technical Monitor)

    2001-01-01

    One of the areas where the thermal protection system on the Space Shuttle Orbiter could be improved is the RSI (Reusable Surface Insulation) tile. The improvement would be in damage resistance that would reduce the resultant maintenance and inspection required. It has performed very well in every other aspect. Improving the system's damage resistance has been the subject of much research over the past several years. One of the results of that research was a new system developed for damage prone areas on the orbiter (i.e., base heat shield). That system, designated as TUFI, Toughened Uni-Piece Fibrous Insulation, was successfully demonstrated as an experiment on the Orbiter and is now baselined for the base heat shield. This paper describes the results of a current research program to further improve the TUFI tile system, thus making it applicable to more areas on the orbiter. The way to remove the current limitations of the TUFI system (i.e., weight or thermal conductivity differences between it and the baseline tile (LI-900)) is to improve the characteristics of LI-900 or AETB-8. Specifically this paper describes the results of two efforts. The first shows performance data of an improved LI-900 system involving the application of TUFI and the second describes data that shows a reduced difference in thermal conductivity between the advanced TUFI substrate (AETB-8) now used on the orbiter and LI-900.

  12. ATLAS tile calorimeter cesium calibration control and analysis software

    NASA Astrophysics Data System (ADS)

    Solovyanov, O.; Solodkov, A.; Starchenko, E.; Karyukhin, A.; Isaev, A.; Shalanda, N.

    2008-07-01

    An online control system to calibrate and monitor ATLAS Barrel hadronic calorimeter (TileCal) with a movable radioactive source, driven by liquid flow, is described. To read out and control the system an online software has been developed, using ATLAS TDAQ components like DVS (Diagnostic and Verification System) to verify the hardware before running, IS (Information Server) for data and status exchange between networked computers, and other components like DDC (DCS to DAQ Connection), to connect to PVSS-based slow control systems of Tile Calorimeter, high voltage and low voltage. A system of scripting facilities, based on Python language, is used to handle all the calibration and monitoring processes from hardware perspective to final data storage, including various abnormal situations. A QT based graphical user interface to display the status of the calibration system during the cesium source scan is described. The software for analysis of the detector response, using online data, is discussed. Performance of the system and first experience from the ATLAS pit are presented.

  13. The ATLAS Tile Calorimeter

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Henriques, A.

    TileCal is the Hadronic calorimeter covering the most central region of the ATLAS experiment at the LHC. It uses iron plates as absorber and plastic scintillating tiles as the active material. Scintillation light produced in the tiles is transmitted by wavelength shifting fibres to photomultiplier tubes (PMTs). The resulting electronic signals from the approximately 10000 PMTs are measured and digitised every 25 ns before being transferred to off-detector data-acquisition systems. This contribution will review in a first part the performances of the calorimeter during run 1, obtained from calibration data, and from studies of the response of particles from collisions.more » In a second part it will present the solutions being investigated for the ongoing and future upgrades of the calorimeter electronics. (authors)« less

  14. Comprehensive nitrogen budgets for controlled tile drainage fields in eastern ontario, Canada.

    PubMed

    Sunohara, M D; Craiovan, E; Topp, E; Gottschall, N; Drury, C F; Lapen, D R

    2014-03-01

    Excessive N loading from subsurface tile drainage has been linked to water quality degradation. Controlled tile drainage (CTD) has the potential to reduce N losses via tile drainage and boost crop yields. While CTD can reduce N loss from tile drainage, it may increase losses through other pathways. A multiple-year field-scale accounting of major N inputs and outputs during the cropping season was conducted on freely drained and controlled tile drained agricultural fields under corn ( L.)-soybean [ (L.) Merr.] production systems in eastern Ontario, Canada. Greater predicted gaseous N emissions for corn and soybean and greater observed lateral seepage N losses were observed for corn and soybean fields under CTD relative to free-draining fields. However, observed N losses from tile were significantly lower for CTD fields, in relation to freely drained fields. Changes in residual soil N were essentially equivalent between drainage treatments, while mass balance residual terms were systematically negative (slightly more so for CTD). Increases in plant N uptake associated with CTD were observed, probably resulting in higher grain yields for corn and soybean. This study illustrates the benefits of CTD in decreasing subsurface tile drainage N losses and boosting crop yields, while demonstrating the potential for CTD to increase N losses via other pathways related to gaseous emissions and groundwater seepage. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  15. Explaining scene composition using kinematic chains of humans: application to Portuguese tiles history

    NASA Astrophysics Data System (ADS)

    da Silva, Nuno Pinho; Marques, Manuel; Carneiro, Gustavo; Costeira, João P.

    2011-03-01

    Painted tile panels (Azulejos) are one of the most representative Portuguese forms of art. Most of these panels are inspired on, and sometimes are literal copies of, famous paintings, or prints of those paintings. In order to study the Azulejos, art historians need to trace these roots. To do that they manually search art image databases, looking for images similar to the representation on the tile panel. This is an overwhelming task that should be automated as much as possible. Among several cues, the pose of humans and the general composition of people in a scene is quite discriminative. We build an image descriptor, combining the kinematic chain of each character, and contextual information about their composition, in the scene. Given a query image, our system computes its similarity profile over the database. Using nearest neighbors in the space of the descriptors, the proposed system retrieves the prints that most likely inspired the tiles' work.

  16. Design and characterization of an ultraresolution seamlessly tiled display for data visualization

    NASA Astrophysics Data System (ADS)

    Bordes, Nicole; Bleha, William P.; Pailthorpe, Bernard

    2003-09-01

    The demand for more pixels in digital displays is beginning to be met as manufacturers increase the native resolution of projector chips. Tiling several projectors still offers one solution to augment the pixel capacity of a display. However problems of color and illumination uniformity across projectors need to be addressed as well as the computer software required to drive such devices. In this paper we present the results obtained on a desktop size tiled projector array of three D-ILA projectors sharing a common illumination source. The composite image on a 3 x 1 array, is 3840 by 1024 pixels with a resolution of about 80 dpi. The system preserves desktop resolution, is compact and can fit in a normal room or laboratory. A fiber optic beam splitting system and a single set of red, green and blue dichroic filters are the key to color and illumination uniformity. The D-ILA chips inside each projector can be adjusted individually to set or change characteristics such as contrast, brightness or gamma curves. The projectors were matched carefully and photometric variations were corrected, leading to a seamless tiled image. Photometric measurements were performed to characterize the display and losses through the optical paths, and are reported here. This system is driven by a small PC computer cluster fitted with graphics cards and is running Linux. The Chromium API can be used for tiling graphics tiles across the display and interfacing to users' software applications. There is potential for scaling the design to accommodate larger arrays, up to 4x5 projectors, increasing display system capacity to 50 Megapixels. Further increases, beyond 100 Megapixels can be anticipated with new generation D-ILA chips capable of projecting QXGA (2k x 1.5k), with ongoing evolution as QUXGA (4k x 2k) becomes available.

  17. Method and system for powering and cooling semiconductor lasers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Telford, Steven J; Ladran, Anthony S

    A semiconductor laser system includes a diode laser tile. The diode laser tile includes a mounting fixture having a first side and a second side opposing the first side and an array of semiconductor laser pumps coupled to the first side of the mounting fixture. The semiconductor laser system also includes an electrical pulse generator thermally coupled to the diode bar and a cooling member thermally coupled to the diode bar and the electrical pulse generator.

  18. [Operative treatment of sacroiliac joint fracture and dislocation in Tile C pelvic fracture with Colorado 2 system].

    PubMed

    Liu, Shuping; Zhou, Qing; Liu, Yuehong; Chen, Xi; Zhou, Yu; Zhang, Desheng; Fang, Zhi; Xu, Wei

    2011-12-01

    To explore the effectiveness of Colorado 2 system in the stability reconstruction of sacroiliac joint fracture and dislocation in Tile C pelvic fracture. Between February 2009 and January 2011, 8 cases of Tile C pelvic fracture were treated with Colorado 2 system. There were 3 males and 5 females with an average age of 34.4 years (range, 22-52 years). Fractures were caused by traffic accident in 3 cases, by falling from height in 3 cases, and by crash of heavy object in 2 cases. According to Tile classification, 5 cases were classified as C1-2, 2 cases as C1-3, and 1 case as C2. The time between injury and operation was 5-10 days (mean, 7 days). After skeletal traction reduction, Colorado 2 system was used to fix sacroiliac joint, and reconstruction plate or external fixation was selectively adopted. The postoperative X-ray films showed that the reduction of vertical and rotatory dislocation was satisfactory, posterior pelvic ring achieved effective stability. All the incisions healed by first intention, and no blood vessel or nerve injury occurred. Eight patients were followed up 6-24 months (mean, 12 months). No loosening or breakage of internal fixation was observed and no re-dislocation of sacroiliac joint occurred. The bone healing time was 6-12 months (mean, 9 months). According to Majeed's functional criterion, the results were excellent in 5 cases, good in 2 cases, and fair in 1 case at last follow-up. Colorado 2 system could provide immediate stability of pelvic posterior ring and good maintenance of reduction effect, which is an effective method in the therapy of sacroiliac joint fracture and dislocation in Tile C pelvic fracture.

  19. Alarm acknowledgement in a nuclear plant control room

    DOEpatents

    Scarola, Kenneth; Jamison, David S.; Manazir, Richard M.; Rescorl, Robert L.; Harmon, Daryl L.

    1994-01-01

    Alarm acknowledgment can be made not only at the alarm tile array of a given console but via other touch sensitive alarm indications in the screen displays of the monitoring system at the same or other consoles; also, touching one tile can acknowledge multiple alarm sources.

  20. Tunable liquid optics: electrowetting-controlled liquid mirrors based on self-assembled Janus tiles.

    PubMed

    Bucaro, Michael A; Kolodner, Paul R; Taylor, J Ashley; Sidorenko, Alex; Aizenberg, Joanna; Krupenkin, Tom N

    2009-04-09

    In this paper, we describe a tunable, high-reflectivity optofluidic device based on self-assembly of anisotropically functionalized hexagonal micromirrors (Janus tiles) on the surface of an oil droplet to create a concave liquid mirror. The liquid mirror is deposited on a patterned transparent electrode that allows the focal length and axial position to be electrically controlled. The mirror is mechanically robust and retains its integrity even at high levels of vibrational excitation of the interface. The use of reflection instead of refraction overcomes the limited available refractive-index contrast between pairs of density-matched liquids, allowing stronger focusing than is possible for a liquid lens of the same geometry. This approach is compatible with optical instruments that could provide novel functionality-for example, a dynamic 3D projector, i.e., a light source which can scan an image onto a moving, nonplanar focal surface. Janus tiles with complex optical properties can be manufactured using our approach, thus potentially enabling a wide range of novel optical elements.

  1. Tunable liquid optics: electrowetting-controlled liquid mirrors based on self-assembled Janus tiles

    NASA Astrophysics Data System (ADS)

    Krupenkin, Tom; Bucaro, Mike; Kolodner, Paul; Taylor, Ashley; Sidorenko, Alex; Aizenberg, Joanna

    2009-03-01

    In this work we describe a tunable, high-reflectivity optofluidic device based on self-assembly of anisotropically-functionalized hexagonal micromirrors (Janus tiles) on the surface of an oil droplet to create a concave liquid mirror. The liquid mirror is deposited on a patterned transparent electrode that allows the focal length and axial position to be electrically controlled. The mirror is mechanically robust and retains its integrity even at high levels of vibrational excitation of the interface. The use of reflection instead of refraction overcomes the limited available refractive-index contrast between pairs of density-matched liquids, allowing stronger focusing than is possible for a liquid lens of the same geometry. This approach is compatible with optical instruments that could provide novel functionality - for example, a dynamic 3D projector; i.e., a light source which can scan an image onto a moving, non-planar focal surface. Janus tiles with complex optical properties can be manufactured using our approach, thus potentially enabling a wide range of novel optical elements.

  2. KSC-2012-1573

    NASA Image and Video Library

    2012-03-01

    CAPE CANAVERAL, Fla. -- Tim Wright, a United Space Alliance engineering manager at NASA's Kennedy Space Center in Florida, unloads the heat shield tiles that will be installed to the backshell of the Orion Multi-Purpose Crew Vehicle's Exploration Flight Test EFT-1 capsule. The tiles are being manufactured and inspected in Kennedy's Thermal Protection System Facility. The tiles will be baked at 2,200 degrees F to cure their ceramic coating. EFT-1 will be used during Orion's first test flight in space. For more information, visit www.nasa.gov/orion. Photo credit: Frankie Martin

  3. Hetero-oligonucleotide Nanoscale Tiles Capable of Two-Dimensional Lattice Formation as Testbeds for a Rapid, Affordable Purification Methodology

    DTIC Science & Technology

    2013-01-01

    SUBJECT TERMS DNA nanotechnology, purification, origami , 2d arrays Philip S. Lukeman St. John’s University, New York 8000 Utopia Parkway Queens, NY... origami ; DNA double-crossover (“DX”) tile based arrays5 have been constructed using PNA6 and LNA7 oligonucleotides. RNA/ DNA duplexes have been used8 for...the assembly of multiply armed tiles9 and as a template10 to fold DNA origami ;11 all-RNA systems known as ‘tecto-RNA’ have been used to generate a wide

  4. Fibrous-Ceramic/Aerogel Composite Insulating Tiles

    NASA Technical Reports Server (NTRS)

    White, Susan M.; Rasky, Daniel J.

    2004-01-01

    Fibrous-ceramic/aerogel composite tiles have been invented to afford combinations of thermal-insulation and mechanical properties superior to those attainable by making tiles of fibrous ceramics alone or aerogels alone. These lightweight tiles can be tailored to a variety of applications that range from insulating cryogenic tanks to protecting spacecraft against re-entry heating. The advantages and disadvantages of fibrous ceramics and aerogels can be summarized as follows: Tiles made of ceramic fibers are known for mechanical strength, toughness, and machinability. Fibrous ceramic tiles are highly effective as thermal insulators in a vacuum. However, undesirably, the porosity of these materials makes them permeable by gases, so that in the presence of air or other gases, convection and gas-phase conduction contribute to the effective thermal conductivity of the tiles. Other disadvantages of the porosity and permeability of fibrous ceramic tiles arise because gases (e.g., water vapor or cryogenic gases) can condense in pores. This condensation contributes to weight, and in the case of cryogenic systems, the heat of condensation undesirably adds to the heat flowing to the objects that one seeks to keep cold. Moreover, there is a risk of explosion associated with vaporization of previously condensed gas upon reheating. Aerogels offer low permeability, low density, and low thermal conductivity, but are mechanically fragile. The basic idea of the present invention is to exploit the best features of fibrous ceramic tiles and aerogels. In a composite tile according to the invention, the fibrous ceramic serves as a matrix that mechanically supports the aerogel, while the aerogel serves as a low-conductivity, low-permeability filling that closes what would otherwise be the open pores of the fibrous ceramic. Because the aerogel eliminates or at least suppresses permeation by gas, gas-phase conduction, and convection, the thermal conductivity of such a composite even at normal atmospheric pressure is not much greater than that of the fibrous ceramic alone in a vacuum.

  5. Biologically inspired crack delocalization in a high strain-rate environment.

    PubMed

    Knipprath, Christian; Bond, Ian P; Trask, Richard S

    2012-04-07

    Biological materials possess unique and desirable energy-absorbing mechanisms and structural characteristics worthy of consideration by engineers. For example, high levels of energy dissipation at low strain rates via triggering of crack delocalization combined with interfacial hardening by platelet interlocking are observed in brittle materials such as nacre, the iridescent material in seashells. Such behaviours find no analogy in current engineering materials. The potential to mimic such toughening mechanisms on different length scales now exists, but the question concerning their suitability under dynamic loading conditions and whether these mechanisms retain their energy-absorbing potential is unclear. This paper investigates the kinematic behaviour of an 'engineered' nacre-like structure within a high strain-rate environment. A finite-element (FE) model was developed which incorporates the pertinent biological design features. A parametric study was carried out focusing on (i) the use of an overlapping discontinuous tile arrangement for crack delocalization and (ii) application of tile waviness (interfacial hardening) for improved post-damage behaviour. With respect to the material properties, the model allows the permutation and combination of a variety of different material datasets. The advantage of such a discontinuous material shows notable improvements in sustaining high strain-rate deformation relative to an equivalent continuous morphology. In the case of the continuous material, the shockwaves propagating through the material lead to localized failure while complex shockwave patterns are observed in the discontinuous flat tile arrangement, arising from platelet interlocking. The influence of the matrix properties on impact performance is investigated by varying the dominant material parameters. The results indicate a deceleration of the impactor velocity, thus delaying back face nodal displacement. A final series of FE models considered the identification of an optimized configuration as a function of tile waviness and matrix properties. In the combined model, the optimized configuration was capable of stopping the ballistic threat, thus indicating the potential for bioinspired toughened synthetic systems to defeat high strain-rate threats.

  6. Biologically inspired crack delocalization in a high strain-rate environment

    PubMed Central

    Knipprath, Christian; Bond, Ian P.; Trask, Richard S.

    2012-01-01

    Biological materials possess unique and desirable energy-absorbing mechanisms and structural characteristics worthy of consideration by engineers. For example, high levels of energy dissipation at low strain rates via triggering of crack delocalization combined with interfacial hardening by platelet interlocking are observed in brittle materials such as nacre, the iridescent material in seashells. Such behaviours find no analogy in current engineering materials. The potential to mimic such toughening mechanisms on different length scales now exists, but the question concerning their suitability under dynamic loading conditions and whether these mechanisms retain their energy-absorbing potential is unclear. This paper investigates the kinematic behaviour of an ‘engineered’ nacre-like structure within a high strain-rate environment. A finite-element (FE) model was developed which incorporates the pertinent biological design features. A parametric study was carried out focusing on (i) the use of an overlapping discontinuous tile arrangement for crack delocalization and (ii) application of tile waviness (interfacial hardening) for improved post-damage behaviour. With respect to the material properties, the model allows the permutation and combination of a variety of different material datasets. The advantage of such a discontinuous material shows notable improvements in sustaining high strain-rate deformation relative to an equivalent continuous morphology. In the case of the continuous material, the shockwaves propagating through the material lead to localized failure while complex shockwave patterns are observed in the discontinuous flat tile arrangement, arising from platelet interlocking. The influence of the matrix properties on impact performance is investigated by varying the dominant material parameters. The results indicate a deceleration of the impactor velocity, thus delaying back face nodal displacement. A final series of FE models considered the identification of an optimized configuration as a function of tile waviness and matrix properties. In the combined model, the optimized configuration was capable of stopping the ballistic threat, thus indicating the potential for bioinspired toughened synthetic systems to defeat high strain-rate threats. PMID:21880614

  7. Self-assembly of Archimedean tilings with enthalpically and entropically patchy polygons.

    PubMed

    Millan, Jaime A; Ortiz, Daniel; van Anders, Greg; Glotzer, Sharon C

    2014-03-25

    Considerable progress in the synthesis of anisotropic patchy nanoplates (nanoplatelets) promises a rich variety of highly ordered two-dimensional superlattices. Recent experiments of superlattices assembled from nanoplates confirm the accessibility of exotic phases and motivate the need for a better understanding of the underlying self-assembly mechanisms. Here, we present experimentally accessible, rational design rules for the self-assembly of the Archimedean tilings from polygonal nanoplates. The Archimedean tilings represent a model set of target patterns that (i) contain both simple and complex patterns, (ii) are comprised of simple regular shapes, and (iii) contain patterns with potentially interesting materials properties. Via Monte Carlo simulations, we propose a set of design rules with general applicability to one- and two-component systems of polygons. These design rules, specified by increasing levels of patchiness, correspond to a reduced set of anisotropy dimensions for robust self-assembly of the Archimedean tilings. We show for which tilings entropic patches alone are sufficient for assembly and when short-range enthalpic interactions are required. For the latter, we show how patchy these interactions should be for optimal yield. This study provides a minimal set of guidelines for the design of anisostropic patchy particles that can self-assemble all 11 Archimedean tilings.

  8. Texture and color features for tile classification

    NASA Astrophysics Data System (ADS)

    Baldrich, Ramon; Vanrell, Maria; Villanueva, Juan J.

    1999-09-01

    In this paper we present the results of a preliminary computer vision system to classify the production of a ceramic tile industry. We focus on the classification of a specific type of tiles whose production can be affected by external factors, such as humidity, temperature, origin of clays and pigments. Variations on these uncontrolled factors provoke small differences in the color and the texture of the tiles that force to classify all the production. A constant and non- subjective classification would allow avoiding devolution from customers and unnecessary stock fragmentation. The aim of this work is to simulate the human behavior on this classification task by extracting a set of features from tile images. These features are induced by definitions from experts. To compute them we need to mix color and texture information and to define global and local measures. In this work, we do not seek a general texture-color representation, we only deal with textures formed by non-oriented colored-blobs randomly distributed. New samples are classified using Discriminant Analysis functions derived from known class tile samples. The last part of the paper is devoted to explain the correction of acquired images in order to avoid time and geometry illumination changes.

  9. Tests with beam setup of the TileCal phase-II upgrade electronics

    NASA Astrophysics Data System (ADS)

    Reward Hlaluku, Dingane

    2017-09-01

    The LHC has planned a series of upgrades culminating in the High Luminosity LHC which will have an average luminosity 5-7 times larger than the nominal Run-2 value. The ATLAS Tile calorimeter plans to introduce a new readout architecture by completely replacing the back-end and front-end electronics for the High Luminosity LHC. The photomultiplier signals will be fully digitized and transferred for every bunch crossing to the off-detector Tile PreProcessor. The Tile PreProcessor will further provide preprocessed digital data to the first level of trigger with improved spatial granularity and energy resolution in contrast to the current analog trigger signals. A single super-drawer module commissioned with the phase-II upgrade electronics is to be inserted into the real detector to evaluate and qualify the new readout and trigger concepts in the overall ATLAS data acquisition system. This new super-drawer, so-called hybrid Demonstrator, must provide analog trigger signals for backward compatibility with the current system. This Demonstrator drawer has been inserted into a Tile calorimeter module prototype to evaluate the performance in the lab. In parallel, one more module has been instrumented with two other front-end electronics options based on custom ASICs (QIE and FATALIC) which are under evaluation. These two modules together with three other modules composed of the current system electronics were exposed to different particles and energies in three test-beam campaigns during 2015 and 2016.

  10. Evaluation of Thermal Protection Tile Transmissibility for Ground Vibration Test

    NASA Technical Reports Server (NTRS)

    Chung, Y. T.; Fowler, Samuel B.; Lo, Wenso; Towner, Robert

    2005-01-01

    Transmissibility analyses and tests were conducted on a composite panel with thermal protection system foams to evaluate the quality of the measured frequency response functions. Both the analysis and the test results indicate that the vehicle dynamic responses are fully transmitted to the accelerometers mounted on the thermal protection system in the normal direction below a certain frequency. In addition, the in-plane motions of the accelerometer mounted on the top surface of the thermal protection system behave more actively than those on the composite panel due to the geometric offset of the accelerometer from the panel in the test set-up. The transmissibility tests and analyses show that the frequency response functions measured from the accelerometers mounted on the TPS will provide accurate vehicle responses below 120 Hz for frequency and mode shape identification. By confirming that accurate dynamic responses below a given frequency can be obtained, this study increases the confidence needed for conducting the modal testing, model correlation, and model updating for a vehicle installed with TPS. '

  11. Pesticide leaching by agricultural drainage in sloping, mid-textured soil conditions - the role of runoff components.

    PubMed

    Zajíček, Antonín; Fučík, Petr; Kaplická, Markéta; Liška, Marek; Maxová, Jana; Dobiáš, Jakub

    2018-04-01

    Dynamics of pesticides and their metabolites in drainage waters during baseflow periods and rainfall-runoff events (RREs) were studied from 2014 to 2016 at three small, tile-drained agricultural catchments in Bohemian-Moravian Highlands, Czech Republic. Drainage systems in this region are typically built in slopes with considerable proportion of drainage runoff originating outside the drained area itself. Continuous monitoring was performed by automated samplers, and the event hydrograph was separated using 18 O and 2 H isotopes and drainage water temperature. Results showed that drainage systems represent a significant source for pesticides leaching from agricultural land. Leaching of pesticide metabolites was mainly associated with baseflow and shallow interflow. Water from causal precipitation diluted their concentrations. The prerequisites for the leaching of parental compounds were a rainfall-runoff event occurring shortly after spraying, and the presence of event water in the runoff. When such situations happened consequently, pesticides concentrations in drainage water were high and the pesticide load reached several grams in a few hours. Presented results introduce new insights into the processes of pesticides movement in small, tile-drained catchments and emphasizes the need to incorporate drainage hydrology and flow-triggered sampling into monitoring programmes in larger catchments as well as in environment-conservation policy.

  12. Effectiveness of conservation practices within watersheds: Case study in tile-drained systems

    USDA-ARS?s Scientific Manuscript database

    The effectiveness of conservation practices are governed in part by the spatial and temporal patterns of water flow as runoff and subsurface (tile) drainage. The variability in patterns of nitrate loss were examined using data from different sized catchments with four CEAP watersheds located in cent...

  13. Mobile Accelerator Neutron Radiography System

    DTIC Science & Technology

    1984-10-01

    panel which is a lamination of ceramic tiles and metal skins, adhesively bonded. The x-ray images the tiles in high contrast, while the neutron...personnel and transported by flatbed truck to its site of operation inside Building 704, a large maintenance hangar located west of the main n:rth-south

  14. Dissipation of atrazine, enrofloxacin, and sulfamethazine in wood chip bioreactors and impact on denitrification

    USDA-ARS?s Scientific Manuscript database

    Wood chip bioreactors are receiving increasing attention as a means of reducing nitrate in subsurface tile drainage systems. Agrochemicals in tile drainage water entering wood chip bioreactors can be retained or degraded and may impact denitrification. The degradation of 5 mg L-1 atrazine, enrofloxa...

  15. Tile Test: A Hands-On Approach for Assessing Phonics in the Early Grades

    ERIC Educational Resources Information Center

    Norman, Kimberly A.; Calfee, Robert C.

    2004-01-01

    An instrument for assessing young students' understanding of the English orthographic system is presented. The Tile Test measures understanding of phoneme awareness, letter-sound correspondences, decoding and spelling of words, sight-word reading, and the application of decoding and spelling in sentences. Metalinguistic questions embedded within…

  16. Foam on Tile Impact Modeling for the Space Shuttle Program

    NASA Technical Reports Server (NTRS)

    Stellingwerf, R. F.; Robinson, J. H.; Richardson, S.; Evans, S. W.; Stallworth, R.; Hovater, M.

    2003-01-01

    Following the breakup of the Space Shuttle Columbia during reentry a NASA-wide investigation team was formed to examine the probable damage inflicted on Orbiter Thermal Protection System (TPS) elements by impact of External Tank insulating foam projectiles. Our team was to apply rigorous, physics-based analysis techniques to help determine parameters of interest for an experimental test program, utilize validated codes to investigate the full range of impact scenarios, and use analysis derived models to predict aero-thermal-structural responses to entry conditions. We were to operate on a non-interference basis with the j Team, and were to supply significant findings to that team and to the Orbiter Vehicle Engineering Working Group, being responsive to any solicitations for support from these entities. The authors formed a working sub-group within the larger team to apply the Smooth Particle Hydrodynamics code SPHC to the damage estimation problem. Numerical models of the LI-900 TPS tiles and of the BX-250 foam were constructed and used as inputs into the code. Material properties needed to properly model the tiles and foam were obtained from other working sub-groups who performed tests on these items for this purpose. Two- and three- dimensional models of the tiles were constructed, including the glass outer layer, the densified lower layer of LI-900 insulation, the Nomex felt Strain Isolation Pad (SIP) mounting layer, and the underlying aluminum 2024 vehicle skin. A model for the BX-250 foam including porous compression, elastic rebound, and surface erosion was developed. Code results for the tile damage and foam behavior were extensively validated through comparison with the Southwest Research Institute (SwRI) foam-on-tile impact experiments carried out in 1999. These tests involved small projectiles striking individual tiles and small tile arrays. Following code and model validation we simulated impacts of larger ET foam projectiles on the TPS tile systems used on the wings of the orbiter. Tiles used on the Wing Acreage, the Main Landing Gear Door, and the Carrier Panels near the front edge of the wing were modeled. Foam impacts shot for the CAB investigation were modeled, as well as impacts at larger angles, including rapid rotation of the projectile, and with varying foam properties. General results suggest that foam impacts on tiles at about 500 mph could cause appreciable damage if the impact angle is greater than about 20 degrees. Some variations of the foam properties, such as increased brittleness or increased density could increase damage in some cases. Rapid (17 rps) rotation failed to increase the damage for the two cases considered. This does not rule out other cases in which the rotational energy might lead to an increase in tile damage, but suggests that in most cases rotation will not be an important factor. Similar models will be applied for other impacting materials, other velocities, and other geometries as part of the Return to Flight process.

  17. Investigation of Tri-Service Heat Distribution Systems (Modernization of Existing Underground Heat Distribution Systems).

    DTIC Science & Technology

    1984-06-01

    carrier pipe is usually insulated with preformed calcium silicate or mineral wool insulation. The preformed insula- tion is secured with stainless steel...glass or mineral wool insula- tion. Each tile is installed in this manner. Repair is difficult, but can be done by local workers with readily available...corrosion S Site I and return lines in of condensate line ( mineral wool insulation). 2. Ft. Campbell, 12 Tile system B No insulation was installed on

  18. Programmable DNA tile self-assembly using a hierarchical sub-tile strategy.

    PubMed

    Shi, Xiaolong; Lu, Wei; Wang, Zhiyu; Pan, Linqiang; Cui, Guangzhao; Xu, Jin; LaBean, Thomas H

    2014-02-21

    DNA tile based self-assembly provides a bottom-up approach to construct desired nanostructures. DNA tiles have been directly constructed from ssDNA and readily self-assembled into 2D lattices and 3D superstructures. However, for more complex lattice designs including algorithmic assemblies requiring larger tile sets, a more modular approach could prove useful. This paper reports a new DNA 'sub-tile' strategy to easily create whole families of programmable tiles. Here, we demonstrate the stability and flexibility of our sub-tile structures by constructing 3-, 4- and 6-arm DNA tiles that are subsequently assembled into 2D lattices and 3D nanotubes according to a hierarchical design. Assembly of sub-tiles, tiles, and superstructures was analyzed using polyacrylamide gel electrophoresis and atomic force microscopy. DNA tile self-assembly methods provide a bottom-up approach to create desired nanostructures; the sub-tile strategy adds a useful new layer to this technique. Complex units can be made from simple parts. The sub-tile approach enables the rapid redesign and prototyping of complex DNA tile sets and tiles with asymmetric designs.

  19. Readiness of the ATLAS Tile Calorimeter for LHC collisions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Aad, G.; Abbott, B.; Abdallah, J.

    The Tile hadronic calorimeter of the ATLAS detector has undergone extensive testing in the experimental hall since its installation in late 2005. The readout, control and calibration systems have been fully operational since 2007 and the detector has successfully collected data from the LHC single beams in 2008 and first collisions in 2009. This paper gives an overview of the Tile Calorimeter performance as measured using random triggers, calibration data, data from cosmic ray muons and single beam data. The detector operation status, noise characteristics and performance of the calibration systems are presented, as well as the validation of themore » timing and energy calibration carried out with minimum ionising cosmic ray muons data. The calibration systems' precision is well below the design value of 1%. The determination of the global energy scale was performed with an uncertainty of 4%. © 2010 CERN for the benefit of the ATLAS collaboration.« less

  20. Readiness of the ATLAS Tile Calorimeter for LHC collisions

    DOE PAGES

    Aad, G.; Abbott, B.; Abdallah, J.; ...

    2010-12-08

    The Tile hadronic calorimeter of the ATLAS detector has undergone extensive testing in the experimental hall since its installation in late 2005. The readout, control and calibration systems have been fully operational since 2007 and the detector has successfully collected data from the LHC single beams in 2008 and first collisions in 2009. This paper gives an overview of the Tile Calorimeter performance as measured using random triggers, calibration data, data from cosmic ray muons and single beam data. The detector operation status, noise characteristics and performance of the calibration systems are presented, as well as the validation of themore » timing and energy calibration carried out with minimum ionising cosmic ray muons data. The calibration systems' precision is well below the design value of 1%. The determination of the global energy scale was performed with an uncertainty of 4%. © 2010 CERN for the benefit of the ATLAS collaboration.« less

  1. KSC01padig216

    NASA Image and Video Library

    2001-05-23

    KENNEDY SPACE CENTER, FLA. -- Banks of lights dry tiles on orbiter Atlantis in the Orbiter Processing Facility. Significant rainstorms during the orbiter’s turnaround for a ferry flight home from Edwards Air Force Base, Calif., caused the moisture problem. The tiles are part of the Thermal Protection System used on orbiters for extreme temperatures encountered during landing

  2. KSC01padig215

    NASA Image and Video Library

    2001-05-23

    KENNEDY SPACE CENTER, FLA. -- Banks of lights dry tiles on orbiter Atlantis in the Orbiter Processing Facility. Significant rainstorms during the orbiter’s turnaround for a ferry flight home from Edwards Air Force Base, Calif., caused the moisture problem. The tiles are part of the Thermal Protection System used on orbiters for extreme temperatures encountered during landing

  3. Chesapeake Bay Breakwater Database Project, Section 227 Demonstration Site: Hurricane Isabel Impacts to Four Breakwater Systems

    DTIC Science & Technology

    2006-07-01

    divided into a series of orthophoto tiles and is stored in a Virginia south, state plane projection, in feet. The aerial photo tiles from VBMP for...Dyke, Aquia Landing, Kingsmill, and Yorktown. The reference mosaic, the 2002 Digital Orthophotos from the Virginia Base Mapping Program (VBMP), is

  4. KSC-2012-1574

    NASA Image and Video Library

    2012-03-01

    CAPE CANAVERAL, Fla. -- Tim Wright, a United Space Alliance engineering manager at NASA's Kennedy Space Center in Florida, put the heat shield tiles that will be installed to the backshell of the Orion Multi-Purpose Crew Vehicle's Exploration Flight Test EFT-1 capsule in a Keith thermal automation oven. The tiles will be baked at 2,200 degrees F to cure their ceramic coating. The work to manufacture and inspect the tiles is taking place in Kennedy's Thermal Protection System Facility. EFT-1 will be used during Orion's first test flight in space. For more information, visit www.nasa.gov/orion. Photo credit: Frankie Martin

  5. KSC-2012-1586

    NASA Image and Video Library

    2012-03-01

    CAPE CANAVERAL, Fla. -- Tim Wright, a United Space Alliance engineering manager at NASA's Kennedy Space Center in Florida, removes the heat shield tiles that will be installed to the backshell of the Orion Multi-Purpose Crew Vehicle's Exploration Flight Test EFT-1 capsule from a Keith thermal automation oven. Inside, the tiles were baked at 2,200 degrees F to cure their ceramic coating. The work to manufacture and inspect the tiles is taking place in Kennedy's Thermal Protection System Facility. EFT-1 will be used during Orion's first test flight in space. For more information, visit www.nasa.gov/orion. Photo credit: Frankie Martin

  6. KSC-2012-1577

    NASA Image and Video Library

    2012-03-01

    CAPE CANAVERAL, Fla. -- Tim Wright, a United Space Alliance engineering manager at NASA's Kennedy Space Center in Florida, removes the heat shield tiles that will be installed to the backshell of the Orion Multi-Purpose Crew Vehicle's Exploration Flight Test EFT-1 capsule from a Keith thermal automation oven. Inside, the tiles were baked at 2,200 degrees F to cure their ceramic coating. The work to manufacture and inspect the tiles is taking place in Kennedy's Thermal Protection System Facility. EFT-1 will be used during Orion's first test flight in space. For more information, visit www.nasa.gov/orion. Photo credit: Frankie Martin

  7. Dissolved organic carbon in runoff and tile-drain water under corn and forage fertilized with hog manure.

    PubMed

    Royer, Isabelle; Angers, Denis A; Chantigny, Martin H; Simard, Régis R; Cluis, Daniel

    2007-01-01

    Dissolved organic carbon (DOC) export from soils can play a significant role in soil C cycling and in nutrient and pollutant transport. However, information about DOC losses from agricultural soils as influenced by management practices is scarce. We compared the effects of mineral fertilizer (MF) and liquid hog manure (LHM) applications on the concentration and molecular size of DOC released in runoff and tile-drain water under corn (Zea mays L.) and forage cropping systems. Runoff and tile-drain water samples were collected during a 2-mo period (October to December 1998) and DOC concentration was measured. Characterization of DOC was performed by tangential ultrafiltration with nominal cut-offs at 3 and 100 kDa. Mean concentration of DOC in runoff water (12.7 mg DOC L(-1)) was higher than in tile-drain water (6.5 mg DOC L(-1)). Incorporation of corn residues increased the DOC concentration by 6- to 17-fold in surface runoff, but this effect was short-lived. In runoff water, the relative size of the DOC molecules increased when corn residues and LHM were applied probably due to partial microbial breakdown of these organic materials and to a faster decomposition or preferential adsorption of the small molecules. The DOC concentration in tile-drain water was slightly higher under forage (7.5 mg DOC L(-1)) than under corn (5.4 mg DOC L(-1)) even though the application rates of LHM were higher in corn plots. We suggest that preferential flow facilitated the migration of DOC to tile drains in forage plots. In conclusion, incorporation of corn residues and LHM increased the concentration of DOC and the relative size of the molecules in surface runoff water, whereas DOC in tile-drain water was mostly influenced by the cropping system with relatively more DOC and larger molecules under forage than corn.

  8. Seamless tiled display system

    NASA Technical Reports Server (NTRS)

    Dubin, Matthew B. (Inventor); Larson, Brent D. (Inventor); Kolosowsky, Aleksandra (Inventor)

    2006-01-01

    A modular and scalable seamless tiled display apparatus includes multiple display devices, a screen, and multiple lens assemblies. Each display device is subdivided into multiple sections, and each section is configured to display a sectional image. One of the lens assemblies is optically coupled to each of the sections of each of the display devices to project the sectional image displayed on that section onto the screen. The multiple lens assemblies are configured to merge the projected sectional images to form a single tiled image. The projected sectional images may be merged on the screen by magnifying and shifting the images in an appropriate manner. The magnification and shifting of these images eliminates any visual effect on the tiled display that may result from dead-band regions defined between each pair of adjacent sections on each display device, and due to gaps between multiple display devices.

  9. Exact coherent structures and chaotic dynamics in a model of cardiac tissue

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Byrne, Greg; Marcotte, Christopher D.; Grigoriev, Roman O., E-mail: roman.grigoriev@physics.gatech.edu

    Unstable nonchaotic solutions embedded in the chaotic attractor can provide significant new insight into chaotic dynamics of both low- and high-dimensional systems. In particular, in turbulent fluid flows, such unstable solutions are referred to as exact coherent structures (ECS) and play an important role in both initiating and sustaining turbulence. The nature of ECS and their role in organizing spatiotemporally chaotic dynamics, however, is reasonably well understood only for systems on relatively small spatial domains lacking continuous Euclidean symmetries. Construction of ECS on large domains and in the presence of continuous translational and/or rotational symmetries remains a challenge. This ismore » especially true for models of excitable media which display spiral turbulence and for which the standard approach to computing ECS completely breaks down. This paper uses the Karma model of cardiac tissue to illustrate a potential approach that could allow computing a new class of ECS on large domains of arbitrary shape by decomposing them into a patchwork of solutions on smaller domains, or tiles, which retain Euclidean symmetries locally.« less

  10. Fpack and Funpack Utilities for FITS Image Compression and Uncompression

    NASA Technical Reports Server (NTRS)

    Pence, W.

    2008-01-01

    Fpack is a utility program for optimally compressing images in the FITS (Flexible Image Transport System) data format (see http://fits.gsfc.nasa.gov). The associated funpack program restores the compressed image file back to its original state (as long as a lossless compression algorithm is used). These programs may be run from the host operating system command line and are analogous to the gzip and gunzip utility programs except that they are optimized for FITS format images and offer a wider choice of compression algorithms. Fpack stores the compressed image using the FITS tiled image compression convention (see http://fits.gsfc.nasa.gov/fits_registry.html). Under this convention, the image is first divided into a user-configurable grid of rectangular tiles, and then each tile is individually compressed and stored in a variable-length array column in a FITS binary table. By default, fpack usually adopts a row-by-row tiling pattern. The FITS image header keywords remain uncompressed for fast access by FITS reading and writing software. The tiled image compression convention can in principle support any number of different compression algorithms. The fpack and funpack utilities call on routines in the CFITSIO library (http://hesarc.gsfc.nasa.gov/fitsio) to perform the actual compression and uncompression of the FITS images, which currently supports the GZIP, Rice, H-compress, and PLIO IRAF pixel list compression algorithms.

  11. Large-area full field x-ray differential phase-contrast imaging using 2D tiled gratings

    NASA Astrophysics Data System (ADS)

    Schröter, Tobias J.; Koch, Frieder J.; Kunka, Danays; Meyer, Pascal; Tietze, Sabrina; Engelhardt, Sabine; Zuber, Marcus; Baumbach, Tilo; Willer, Konstantin; Birnbacher, Lorenz; Prade, Friedrich; Pfeiffer, Franz; Reichert, Klaus-Martin; Hofmann, Andreas; Mohr, Jürgen

    2017-06-01

    Grating-based x-ray differential phase-contrast imaging (DPCI) is capable of acquiring information based on phase-shift and dark-field signal, in addition to conventional x-ray absorption-contrast. Thus DPCI gives an advantage to investigate composite materials with component wise similar absorption properties like soft tissues. Due to technological challenges in fabricating high quality gratings over a large extent, the field of view (FoV) of the imaging systems is limited to a grating area of a couple of square centimeters. For many imaging applications (e.g. in medicine), however, a FoV that ranges over several ten centimeters is needed. In this manuscript we propose to create large area gratings of theoretically any extent by assembling a number of individual grating tiles. We discuss the precision needed for alignment of each microstructure tile in order to reduce image artifacts and to preserve minimum 90% of the sensitivity obtainable with a monolithic grating. To achieve a reliable high precision alignment a semiautomatic assembly system consisting of a laser autocollimator, a digital microscope and a force sensor together with positioning devices was built. The setup was used to tile a first four times four analyzer grating with a size of 200 mm  ×  200 mm together with a two times two phase grating. First imaging results prove the applicability and quality of the tiling concept.

  12. Morphology-Induced Collective Behaviors: Dynamic Pattern Formation in Water-Floating Elements

    PubMed Central

    Nakajima, Kohei; Ngouabeu, Aubery Marchel Tientcheu; Miyashita, Shuhei; Göldi, Maurice; Füchslin, Rudolf Marcel; Pfeifer, Rolf

    2012-01-01

    Complex systems involving many interacting elements often organize into patterns. Two types of pattern formation can be distinguished, static and dynamic. Static pattern formation means that the resulting structure constitutes a thermodynamic equilibrium whose pattern formation can be understood in terms of the minimization of free energy, while dynamic pattern formation indicates that the system is permanently dissipating energy and not in equilibrium. In this paper, we report experimental results showing that the morphology of elements plays a significant role in dynamic pattern formation. We prepared three different shapes of elements (circles, squares, and triangles) floating in a water-filled container, in which each of the shapes has two types: active elements that were capable of self-agitation with vibration motors, and passive elements that were mere floating tiles. The system was purely decentralized: that is, elements interacted locally, and subsequently elicited global patterns in a process called self-organized segregation. We showed that, according to the morphology of the selected elements, a different type of segregation occurs. Also, we quantitatively characterized both the local interaction regime and the resulting global behavior for each type of segregation by means of information theoretic quantities, and showed the difference for each case in detail, while offering speculation on the mechanism causing this phenomenon. PMID:22715370

  13. Tile Drainage Density Reduces Groundwater Travel Times and Compromises Riparian Buffer Effectiveness.

    PubMed

    Schilling, Keith E; Wolter, Calvin F; Isenhart, Thomas M; Schultz, Richard C

    2015-11-01

    Strategies to reduce nitrate-nitrogen (nitrate) pollution delivered to streams often seek to increase groundwater residence time to achieve measureable results, yet the effects of tile drainage on residence time have not been well documented. In this study, we used a geographic information system groundwater travel time model to quantify the effects of artificial subsurface drainage on groundwater travel times in the 7443-ha Bear Creek watershed in north-central Iowa. Our objectives were to evaluate how mean groundwater travel times changed with increasing drainage intensity and to assess how tile drainage density reduces groundwater contributions to riparian buffers. Results indicate that mean groundwater travel times are reduced with increasing degrees of tile drainage. Mean groundwater travel times decreased from 5.6 to 1.1 yr, with drainage densities ranging from 0.005 m (7.6 mi) to 0.04 m (62 mi), respectively. Model simulations indicate that mean travel times with tile drainage are more than 150 times faster than those that existed before settlement. With intensive drainage, less than 2% of the groundwater in the basin appears to flow through a perennial stream buffer, thereby reducing the effectiveness of this practice to reduce stream nitrate loads. Hence, strategies, such as reconnecting tile drainage to buffers, are promising because they increase groundwater residence times in tile-drained watersheds. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  14. Quantitative Campylobacter spp., antibiotic resistance genes, and veterinary antibiotics in surface and ground water following manure application: Influence of tile drainage control.

    PubMed

    Frey, Steven K; Topp, Edward; Khan, Izhar U H; Ball, Bonnie R; Edwards, Mark; Gottschall, Natalie; Sunohara, Mark; Lapen, David R

    2015-11-01

    This work investigated chlortetracycline, tylosin, and tetracycline (plus transformation products), and DNA-based quantitative Campylobacter spp. and Campylobacter tetracycline antibiotic resistant genes (tet(O)) in tile drainage, groundwater, and soil before and following a liquid swine manure (LSM) application on clay loam plots under controlled (CD) and free (FD) tile drainage. Chlortetracycline/tetracycline was strongly bound to manure solids while tylosin dominated in the liquid portion of manure. The chlortetracycline transformation product isochlortetracycline was the most persistent analyte in water. Rhodamine WT (RWT) tracer was mixed with manure and monitored in tile and groundwater. RWT and veterinary antibiotic (VA) concentrations were strongly correlated in water which supported the use of RWT as a surrogate tracer. While CD reduced tile discharge and eliminated application-induced VA movement (via tile) to surface water, total VA mass loading to surface water was not affected by CD. At both CD and FD test plots, the biggest 'flush' of VA mass and highest VA concentrations occurred in response to precipitation received 2d after application, which strongly influenced the flow abatement capacity of CD on account of highly elevated water levels in field initiating overflow drainage for CD systems (when water level <0.3m below surface). VA concentrations in tile and groundwater became very low within 10d following application. Both Campylobacter spp. and Campylobacter tet(O) genes were present in groundwater and soil prior to application, and increased thereafter. Unlike the VA compounds, Campylobacter spp. and Campylobacter tet(O) gene loadings in tile drainage were reduced by CD, in relation to FD. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

  15. Large Coded Aperture Mask for Spaceflight Hard X-ray Images

    NASA Technical Reports Server (NTRS)

    Vigneau, Danielle N.; Robinson, David W.

    2002-01-01

    The 2.6 square meter coded aperture mask is a vital part of the Burst Alert Telescope on the Swift mission. A random, but known pattern of more than 50,000 lead tiles, each 5 mm square, was bonded to a large honeycomb panel which projects a shadow on the detector array during a gamma ray burst. A two-year development process was necessary to explore ideas, apply techniques, and finalize procedures to meet the strict requirements for the coded aperture mask. Challenges included finding a honeycomb substrate with minimal gamma ray attenuation, selecting an adhesive with adequate bond strength to hold the tiles in place but soft enough to allow the tiles to expand and contract without distorting the panel under large temperature gradients, and eliminating excess adhesive from all untiled areas. The largest challenge was to find an efficient way to bond the > 50,000 lead tiles to the panel with positional tolerances measured in microns. In order to generate the desired bondline, adhesive was applied and allowed to cure to each tile. The pre-cured tiles were located in a tool to maintain positional accuracy, wet adhesive was applied to the panel, and it was lowered to the tile surface with synchronized actuators. Using this procedure, the entire tile pattern was transferred to the large honeycomb panel in a single bond. The pressure for the bond was achieved by enclosing the entire system in a vacuum bag. Thermal vacuum and acoustic tests validated this approach. This paper discusses the methods, materials, and techniques used to fabricate this very large and unique coded aperture mask for the Swift mission.

  16. Managing tile drainage, subirrigation, and nitrogen fertilization to enhance crop yields and reduce nitrate loss.

    PubMed

    Drury, C F; Tan, C S; Reynolds, W D; Welacky, T W; Oloya, T O; Gaynor, J D

    2009-01-01

    Improving field-crop use of fertilizer nitrogen is essential for protecting water quality and increasing crop yields. The objective of this study was to determine the effectiveness of controlled tile drainage (CD) and controlled tile drainage with subsurface irrigation (CDS) for mitigating off-field nitrate losses and enhancing crop yields. The CD and CDS systems were compared on a clay loam soil to traditional unrestricted tile drainage (UTD) under a corn (Zea Mays L.)-soybean (Glycine Max. (L.) Merr.) rotation at two nitrogen (N) fertilization rates (N1: 150 kg N ha(-1) applied to corn, no N applied to soybean; N2: 200 kg N ha(-1) applied to corn, 50 kg N ha(-1) applied to soybean). The N concentrations in tile flow events with the UTD treatment exceeded the provisional long-term aquatic life limit (LT-ALL) for freshwater (4.7 mg N L(-1)) 72% of the time at the N1 rate and 78% at the N2 rate, whereas only 24% of tile flow events at N1 and 40% at N2 exceeded the LT-ALL for the CDS treatment. Exceedances in N concentration for surface runoff and tile drainage were greater during the growing season than the non-growing season. At the N1 rate, CD and CDS reduced average annual N losses via tile drainage by 44 and 66%, respectively, relative to UTD. At the N2 rate, the average annual decreases in N loss were 31 and 68%, respectively. Crop yields from CDS were increased by an average of 2.8% relative to UTD at the N2 rate but were reduced by an average of 6.5% at the N1 rate. Hence, CD and CDS were effective for reducing average nitrate losses in tile drainage, but CDS increased average crop yields only when additional N fertilizer was applied.

  17. Divertor sheath power studies in DIII-D using fixed Langmuir probes and three-dimensional modeling of tile heat flows

    NASA Astrophysics Data System (ADS)

    Donovan, D.; Nygren, R.; Buchenauer, D.; Watkins, J.; Rudakov, D.; Leonard, A.; Wong, C. P. C.; Makowski, M.

    2014-04-01

    Experimental results are presented from the three-Langmuir probe (LP) diagnostic head of the divertor material evaluation system (DiMES) on DIII-D that confirm the size of the projected current collection area of the LPs, which is essential for properly measuring ion saturation current density (Jsat) and the sheath power transmission factor (SPTF). Also using the 3-LP DiMES head, the hypothesis that collisional effects on plasma density occurring in the magnetic sheath of the tile are responsible for a lower than expected SPTF is tested and deemed not to have a significant impact on the SPTF. Three-dimensional thermal modeling of wall tiles is presented that accounts for lateral heat conduction, temperature dependence of tile material properties and radiative heat loss from the tile surface. This modeling was developed to be used in the analysis of temperature profiles of the divertor embedded thermocouple (TC) array to obtain more accurate interpretations of TC temperature profiles to infer divertor surface heat flux than have previously been accomplished using more basic one-dimensional methods.

  18. ATLAS Tile Calorimeter calibration and monitoring systems

    NASA Astrophysics Data System (ADS)

    Cortés-González, Arely

    2018-01-01

    The ATLAS Tile Calorimeter is the central section of the hadronic calorimeter of the ATLAS experiment and provides important information for reconstruction of hadrons, jets, hadronic decays of tau leptons and missing transverse energy. This sampling calorimeter uses steel plates as absorber and scintillating tiles as active medium. The light produced by the passage of charged particles is transmitted by wavelength shifting fibres to photomultiplier tubes, located in the outer part of the calorimeter. Neutral particles may also produce a signal after interacting with the material and producing charged particles. The readout is segmented into about 5000 cells, each of them being read out by two photomultipliers in parallel. To calibrate and monitor the stability and performance of each part of the readout chain during the data taking, a set of calibration systems is used. This comprises Cesium radioactive sources, Laser, charge injection elements and an integrator based readout system. Information from all systems allows to monitor and equalise the calorimeter response at each stage of the signal production, from scintillation light to digitisation. Calibration runs are monitored from a data quality perspective and used as a cross-check for physics runs. The data quality efficiency achieved during 2016 was 98.9%. These calibration and stability of the calorimeter reported here show that the TileCal performance is within the design requirements and has given essential contribution to reconstructed objects and physics results.

  19. Tile-in-ONE: A web platform which integrates Tile Calorimeter data quality and calibration assessment

    NASA Astrophysics Data System (ADS)

    Sivolella, A.; Ferreira, F.; Maidantchik, C.; Solans, C.; Solodkov, A.; Burghgrave, B.; Smirnov, Y.

    2015-12-01

    The ATLAS Tile Calorimeter collaboration assesses the quality of calibration data in order to ensure its proper operation. A number of tasks is then performed by executing several tools and accessing web systems, which were independently developed to meet distinct collaboration's requirements and do not necessarily are connected with each other. Thus, to attend the collaboration needs, several programs are usually implemented without a global perspective of the detector, requiring basic software features. In addition, functionalities may overlap in their objectives and frequently replicate resources retrieval mechanisms. Tile-in-ONE is a designed and implemented platform that assembles various web systems used by the calorimeter community through a single framework and a standard technology. It provides an infrastructure to support the code implementation, avoiding duplication of work while integrating with an overall view of the detector status. Database connectors smooth the process of information access since developers do not need to be aware of where records are placed and how to extract them. Within the environment, a dashboard stands for a particular Tile operation aspect and gets together plug-ins, i.e. software components that add specific features to an existing application. A server contains the platform core, which represents the basic environment to deal with the configuration, manage user settings and load plug-ins at runtime. A web middleware assists users to develop their own plug-ins, perform tests and integrate them into the platform as a whole. Backends are employed to allow that any type of application is interpreted and displayed in a uniform way. This paper describes Tile-in-ONE web platform.

  20. Using AnnAGNPS to Predict the Effects of Tile Drainage Control on Nutrient and Sediment Loads for a River Basin.

    PubMed

    Que, Z; Seidou, O; Droste, R L; Wilkes, G; Sunohara, M; Topp, E; Lapen, D R

    2015-03-01

    Controlled tile drainage (CTD) can reduce pollutant loading. The Annualized Agricultural Nonpoint Source model (AnnAGNPS version 5.2) was used to examine changes in growing season discharge, sediment, nitrogen, and phosphorus loads due to CTD for a ∼3900-km agriculturally dominated river basin in Ontario, Canada. Two tile drain depth scenarios were examined in detail to mimic tile drainage control for flat cropland: 600 mm depth (CTD) and 200 mm (CTD) depth below surface. Summed for five growing seasons (CTD), direct runoff, total N, and dissolved N were reduced by 6.6, 3.5, and 13.7%, respectively. However, five seasons of summed total P, dissolved P, and total suspended solid loads increased as a result of CTD by 0.96, 1.6, and 0.23%. The AnnAGNPS results were compared with mass fluxes observed from paired experimental watersheds (250, 470 ha) in the river basin. The "test" experimental watershed was dominated by CTD and the "reference" watershed by free drainage. Notwithstanding environmental/land use differences between the watersheds and basin, comparisons of seasonal observed and predicted discharge reductions were comparable in 100% of respective cases. Nutrient load comparisons were more consistent for dissolved, relative to particulate water quality endpoints. For one season under corn crop production, AnnAGNPS predicted a 55% decrease (CTD) in dissolved N from the basin. AnnAGNPS v. 5.2 treats P transport from a surface pool perspective, which is appropriate for many systems. However, for assessment of tile drainage management practices for relatively flat tile-dominated systems, AnnAGNPS may benefit from consideration of P and particulate transport in the subsurface. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  1. Penrose high-dynamic-range imaging

    NASA Astrophysics Data System (ADS)

    Li, Jia; Bai, Chenyan; Lin, Zhouchen; Yu, Jian

    2016-05-01

    High-dynamic-range (HDR) imaging is becoming increasingly popular and widespread. The most common multishot HDR approach, based on multiple low-dynamic-range images captured with different exposures, has difficulties in handling camera and object movements. The spatially varying exposures (SVE) technology provides a solution to overcome this limitation by obtaining multiple exposures of the scene in only one shot but suffers from a loss in spatial resolution of the captured image. While aperiodic assignment of exposures has been shown to be advantageous during reconstruction in alleviating resolution loss, almost all the existing imaging sensors use the square pixel layout, which is a periodic tiling of square pixels. We propose the Penrose pixel layout, using pixels in aperiodic rhombus Penrose tiling, for HDR imaging. With the SVE technology, Penrose pixel layout has both exposure and pixel aperiodicities. To investigate its performance, we have to reconstruct HDR images in square pixel layout from Penrose raw images with SVE. Since the two pixel layouts are different, the traditional HDR reconstruction methods are not applicable. We develop a reconstruction method for Penrose pixel layout using a Gaussian mixture model for regularization. Both quantitative and qualitative results show the superiority of Penrose pixel layout over square pixel layout.

  2. Ground Based, Millimeter Wave Measurement of Ozone in the Middle Atmosphere

    NASA Technical Reports Server (NTRS)

    Parrish, Alan

    2000-01-01

    There is a need for highly reliable measurements of stratospheric ozone. Policy makers worldwide concerned with public health rely oil a clear consensus from the scientific community as a basis for ozone-related environmental policy that has a significant impact oil national economies. Tile latest Such consensus was presented in WMO, and used in a 1999 meeting of the parties considering amendments to the Montreal Protocol oil Substances that Deplete the Ozone Layer. Tile scientific community, in turn, needs highly precise and accurate measurements of ozone levels, and small time derivatives of these levels, both in continued - development of its understanding of the physical and chemical processes involved and as clear evidence that these processes are occurring as stated. Over most of the world, changes in ozone levels are small. For example, over the heavily populated northern midlatitudes, the linearized rate of ozone decline is between 0.2% per year and 0.7% per year, depending on altitude. These values are small enough to make measurement requirements technically challenging. Data quality may suffer from imperfections in individual instruments. In one instance, early results from a satellite-borne ozone sensor were later found to be invalid because of calibration drift. Even in the absence of drift, tile absolute calibration of a new sensor may differ slightly from that of its predecessor in service. Most ozone remote sensing instruments operate at ultraviolet or infrared wavelengths where scattering from dust and aerosols must be taken into account; results from these systems may be or are affected following a major volcanic eruption, such as tile one at Mt. Pinatubo in 1991. Given these difficulties, a consensus of measurements from several independent systems is required to insure a reliable understanding of stratospheric ozone levels. Because of the above-described need for highly precise and accurate ozone measurements using several independent techniques, there was interest in developing several techniques which were known but not highly developed in the 1980's into systems capable of being used in ail operational manner to make measurements with the level of quality needed to-detect small trends in ozone levels. A ground-based microwave instrument capable of remotely sensing stratospheric ozone had been designed by tile Principal Investigator of the present project. This instrument was built at tile Millitech Corporation in South Deerfield, Massachusetts before tile present work began. (Funding for design and construction of the instrument came from sources other than the present grant.) Tile instrument measured the spectrum of one of the many emission lines produced by purely rotational transitions of ozone, one at a frequency of 110.8 GHz. The altitude distribution of ozone can. in principle, be retrieved from the details of the pressure-broadened spectrum of the ozone transition. However, the level of contamination of the spectral measurement by instrumentally induced artifacts must be very low in order to retrieve a ozone profile of useful quality from it. The Millitech instrument demonstrated spectral purity at ail adequate level, and there were promising ideas for instrumental improvements and for further development of the technique. The initial objectives of the present project, then, were to develop techniques for calibrating the Millitech instrument, to minimize artifacts in tile spectra it produces, to optimally retrieve ozone profiles from tile spectra, to test tile quality of the microwave profiles by comparing them with profiles obtained using several other, independent techniques over both short and periods of time, and to perform research using the ozone data gathered with the instrument.

  3. The use of waste ceramic tile in cement production

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ay, N.; Uenal, M.

    In ceramic tile production, because of various reasons, unsold fired products come out. These are waste tiles and only a little part of them are used. Remainings create environmental problems. If these waste tiles are used in cement production, this pollution decreases. In this study, usage of waste tile as pozzolan was studied. Waste tile was added into Portland cement in 25%, 30%, 35%, and 40% weight ratios. Pozzolanic properties of waste tile and setting time, volume stability, particle size, density, specific surface area, and strength of cement including waste tile were investigated. The test results indicated that the wastemore » tiles show pozzolanic properties, and chemical and physical properties of the cement including tile conforms to cement standard up to the addition of 35% waste tile.« less

  4. Consequences of Spatial Antisymmetry on Light

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mascarenhas, Angelo; Fluegel, Brian

    2016-12-21

    Light propagation in two and three dimensional lattices for which the index of refraction exhibits spatial antisymmetry is investigated in the ray and photonic crystal regimes. In these regimes, all the two dimensional antisymmetry groups for which light fails to propagate are identified. In the ray-regime, it is observed that in tilings described by 7 of the 46 two dimensional antisymmetric groups, light is localized within a fundamental domain and does not propagate through the tiling, in contrast to the behavior in the other 39 groups. To understand the above phenomenon, a rule based on the number of anti-mirror planesmore » passing through a single Bravais lattice point is derived. In the wave regime for photonic crystals, it is observed that there are no propagating eigensolutions for the same 7 tilings as above, whereas propagating solutions and energy pass band dispersion curves can be obtained for the other 39 groups. The reasons underlying this peculiar behavior are analyzed using the topological approach for modeling flow in dynamical billiards to shed light on the applicability of Bloch's theorem for these periodic antisymmetric lattices.« less

  5. The effect of surface waviness on friction between Neolite and quarry tiles.

    PubMed

    Chang, Wen-Ruey; Grönqvist, Raoul; Hirvonen, Mikko; Matz, Simon

    2004-06-22

    Friction is widely used as an indicator of surface slipperiness in preventing accidents in slips and falls. Surface texture affects friction, but it is not clear which surface characteristics are better correlated with friction. Highly correlated surface characteristics could be used as potential interventions to prevent slip and fall accidents. The dynamic friction between quarry tiles and a commonly used sole testing material, Neolite, using three different mixtures of glycerol and water as contaminants at the interface was correlated with the surface parameters of the tile surfaces. The surface texture was quantified with various surface roughness and surface waviness parameters using three different cut-off lengths to filter the measured profiles for obtaining the profiles of either surface roughness or surface waviness. The correlation coefficients between the surface parameters and the measured friction were affected by the glycerol contents and cut-off lengths. Surface waviness parameters could potentially be better indicators of friction than commonly used surface roughness parameters, especially when they were measured with commonly used cut-off lengths or when the viscosity of the liquid contaminant was high.

  6. Steady internal flow and aerodynamic loads analysis of shuttle thermal protection system

    NASA Technical Reports Server (NTRS)

    Petley, D. H.; Alexander, W., Jr.; Ivey, G. W., Jr.; Kerr, P. A.

    1984-01-01

    An analytical model for calculation of ascent steady state tile loading was developed and validated with wind tunnel data. The analytical model is described and results are given. Results are given for loading due to shocks and skin friction. The analysis included calculation of internal flow (porous media flow and channel flow) to obtain pressures and integration of the pressures to obtain forces and moments on an insulation tile. A heat transfer program was modified by using analogies between heat transfer and fluid flow so that it could be used for internal flow calculation. The type of insulation tile considered was undensified reusable surface insulation (RSI) without gap fillers, and the location studied was the lower surface of the orbiter. Force and moment results are reported for parameter variations on surface pressure distribution, gap sizes, insulation permeability, and tile thickness.

  7. The Equivalent Thermal Resistance of Tile Roofs with and without Batten Systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Miller, William A

    Clay and concrete tile roofs were installed on a fully instrumented attic test facility operating in East Tennessee s climate. Roof, attic and deck temperatures and heat flows were recorded for each of the tile roofs and also on an adjacent attic cavity covered with a conventionally pigmented and direct-nailed asphalt shingle roof. The data were used to benchmark a computer tool for simulation of roofs and attics and the tool used to develop an approach for computing an equivalent seasonal R-value for sub-tile venting. The approach computed equal heat fluxes through the ceilings of roofs having different combinations ofmore » surface radiation properties and or building constructions. A direct nailed shingle roof served as a control for estimating the equivalent thermal resistance of the air space. Simulations were benchmarked to data in the ASHRAE Fundamentals for the thermal resistance of inclined and closed air spaces.« less

  8. Plasma Chamber and First Wall of the Ignitor Experiment^*

    NASA Astrophysics Data System (ADS)

    Cucchiaro, A.; Coppi, B.; Bianchi, A.; Lucca, F.

    2005-10-01

    The new designs of the Plasma Chamber (PC) and of the First Wall (FW) system are based on updated scenarios for vertical plasma disruption (VDE) as well as estimates for the maximum thermal wall loadings at ignition. The PC wall thickness has been optimized to reduce the deformation during the worst disruption event without sacrificing the dimensions of the plasma column. A non linear dynamic analysis of the PC has been performed on a 360^o model of it, taking into account possible toroidal asymmetries of the halo current. Radial EM loads obtained by scaling JET measurements have been also considered. The low-cycle fatigue analysis confirms that the PC is able to meet a lifetime of few thousand cycles for the most extreme combinations of magnetic fields and plasma currents. The FW, made of Molybdenum (TZM) tiles covering the entire inner surface of the PC, has been designed to withstand thermal and EM loads, both under normal operating conditions and in case of disruption. Detailed elasto-plastic structural analyses of the most (EM) loaded tile-carriers show that these are compatible with the adopted fabrication requirements. ^*Sponsored in part by ENEA of Italy and by the U.S. DOE.

  9. Performance modeling of the effects of aperture phase error, turbulence, and thermal blooming on tiled subaperture systems

    NASA Astrophysics Data System (ADS)

    Leakeas, Charles L.; Capehart, Shay R.; Bartell, Richard J.; Cusumano, Salvatore J.; Whiteley, Matthew R.

    2011-06-01

    Laser weapon systems comprised of tiled subapertures are rapidly emerging in importance in the directed energy community. Performance models of these laser weapon systems have been developed from numerical simulations of a high fidelity wave-optics code called WaveTrain which is developed by MZA Associates. System characteristics such as mutual coherence, differential jitter, and beam quality rms wavefront error are defined for a focused beam on the target. Engagement scenarios are defined for various platform and target altitudes, speeds, headings, and slant ranges along with the natural wind speed and heading. Inputs to the performance model include platform and target height and velocities, Fried coherence length, Rytov number, isoplanatic angle, thermal blooming distortion number, Greenwood and Tyler frequencies, and atmospheric transmission. The performance model fit is based on power-in-the-bucket (PIB) values against the PIB from the simulation results for the vacuum diffraction-limited spot size as the bucket. The goal is to develop robust performance models for aperture phase error, turbulence, and thermal blooming effects in tiled subaperture systems.

  10. Image alignment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dowell, Larry Jonathan

    Disclosed is a method and device for aligning at least two digital images. An embodiment may use frequency-domain transforms of small tiles created from each image to identify substantially similar, "distinguishing" features within each of the images, and then align the images together based on the location of the distinguishing features. To accomplish this, an embodiment may create equal sized tile sub-images for each image. A "key" for each tile may be created by performing a frequency-domain transform calculation on each tile. A information-distance difference between each possible pair of tiles on each image may be calculated to identify distinguishingmore » features. From analysis of the information-distance differences of the pairs of tiles, a subset of tiles with high discrimination metrics in relation to other tiles may be located for each image. The subset of distinguishing tiles for each image may then be compared to locate tiles with substantially similar keys and/or information-distance metrics to other tiles of other images. Once similar tiles are located for each image, the images may be aligned in relation to the identified similar tiles.« less

  11. KSC-04pd1902

    NASA Image and Video Library

    2004-09-22

    KENNEDY SPACE CENTER, FLA. - Workers attempt to secure the roof of the Tile Shop in the Thermal Protection System Facility (TPSF) in preparation for Hurricane Jeanne, which is expected to impact Central Florida Sunday. The TPSF, which creates the TPS tiles, blankets and all the internal thermal control systems for the Space Shuttles, lost approximately 35 percent of its roof during Hurricane Frances, which blew across Central Florida Sept. 4. Jeanne is the fourth hurricane in 45 days to make landfall somewhere in the state.

  12. Orbiter Boom Sensor System and TPS tiles on orbiter Discovery as seen during EVA 3

    NASA Image and Video Library

    2005-08-03

    S114-E-6310 (3 August 2005) --- The Red Sea forms the backdrop for this view featuring a portion of thermal protection tiles on the Space Shuttle Discovery’s underside and the Canadian-built remote manipulator system (RMS) robotic arm while docked to the international space station during the STS-114 mission. The image was photographed by astronaut Stephen K. Robinson (out of frame), mission specialist, during today’s extravehicular activities (EVA).

  13. An accurate algorithm to match imperfectly matched images for lung tumor detection without markers

    PubMed Central

    Rozario, Timothy; Bereg, Sergey; Yan, Yulong; Chiu, Tsuicheng; Liu, Honghuan; Kearney, Vasant; Jiang, Lan

    2015-01-01

    In order to locate lung tumors on kV projection images without internal markers, digitally reconstructed radiographs (DRRs) are created and compared with projection images. However, lung tumors always move due to respiration and their locations change on projection images while they are static on DRRs. In addition, global image intensity discrepancies exist between DRRs and projections due to their different image orientations, scattering, and noises. This adversely affects comparison accuracy. A simple but efficient comparison algorithm is reported to match imperfectly matched projection images and DRRs. The kV projection images were matched with different DRRs in two steps. Preprocessing was performed in advance to generate two sets of DRRs. The tumors were removed from the planning 3D CT for a single phase of planning 4D CT images using planning contours of tumors. DRRs of background and DRRs of tumors were generated separately for every projection angle. The first step was to match projection images with DRRs of background signals. This method divided global images into a matrix of small tiles and similarities were evaluated by calculating normalized cross‐correlation (NCC) between corresponding tiles on projections and DRRs. The tile configuration (tile locations) was automatically optimized to keep the tumor within a single projection tile that had a bad matching with the corresponding DRR tile. A pixel‐based linear transformation was determined by linear interpolations of tile transformation results obtained during tile matching. The background DRRs were transformed to the projection image level and subtracted from it. The resulting subtracted image now contained only the tumor. The second step was to register DRRs of tumors to the subtracted image to locate the tumor. This method was successfully applied to kV fluoro images (about 1000 images) acquired on a Vero (BrainLAB) for dynamic tumor tracking on phantom studies. Radiation opaque markers were implanted and used as ground truth for tumor positions. Although other organs and bony structures introduced strong signals superimposed on tumors at some angles, this method accurately located tumors on every projection over 12 gantry angles. The maximum error was less than 2.2 mm, while the total average error was less than 0.9 mm. This algorithm was capable of detecting tumors without markers, despite strong background signals. PACS numbers: 87.57.cj, 87.57.cp87.57.nj, 87.57.np, 87.57.Q‐, 87.59.bf, 87.63.lm

  14. Hierarchical Self Assembly of Patterns from the Robinson Tilings: DNA Tile Design in an Enhanced Tile Assembly Model

    PubMed Central

    Padilla, Jennifer E.; Liu, Wenyan; Seeman, Nadrian C.

    2012-01-01

    We introduce a hierarchical self assembly algorithm that produces the quasiperiodic patterns found in the Robinson tilings and suggest a practical implementation of this algorithm using DNA origami tiles. We modify the abstract Tile Assembly Model, (aTAM), to include active signaling and glue activation in response to signals to coordinate the hierarchical assembly of Robinson patterns of arbitrary size from a small set of tiles according to the tile substitution algorithm that generates them. Enabling coordinated hierarchical assembly in the aTAM makes possible the efficient encoding of the recursive process of tile substitution. PMID:23226722

  15. Hierarchical Self Assembly of Patterns from the Robinson Tilings: DNA Tile Design in an Enhanced Tile Assembly Model.

    PubMed

    Padilla, Jennifer E; Liu, Wenyan; Seeman, Nadrian C

    2012-06-01

    We introduce a hierarchical self assembly algorithm that produces the quasiperiodic patterns found in the Robinson tilings and suggest a practical implementation of this algorithm using DNA origami tiles. We modify the abstract Tile Assembly Model, (aTAM), to include active signaling and glue activation in response to signals to coordinate the hierarchical assembly of Robinson patterns of arbitrary size from a small set of tiles according to the tile substitution algorithm that generates them. Enabling coordinated hierarchical assembly in the aTAM makes possible the efficient encoding of the recursive process of tile substitution.

  16. Upgrade of Tile Calorimeter of the ATLAS Detector for the High Luminosity LHC.

    NASA Astrophysics Data System (ADS)

    Valdes Santurio, Eduardo; Tile Calorimeter System, ATLAS

    2017-11-01

    The Tile Calorimeter (TileCal) is the hadronic calorimeter of ATLAS covering the central region of the ATLAS experiment. TileCal is a sampling calorimeter with steel as absorber and scintillators as active medium. The scintillators are read out by wavelength shifting fibers coupled to photomultiplier tubes (PMT). The analogue signals from the PMTs are amplified, shaped and digitized by sampling the signal every 25 ns. The High Luminosity Large Hadron Collider (HL-LHC) will have a peak luminosity of 5 × 1034 cm -2 s -1, five times higher than the design luminosity of the LHC. TileCal will undergo a major replacement of its on- and off-detector electronics for the high luminosity programme of the LHC in 2026. The calorimeter signals will be digitized and sent directly to the off-detector electronics, where the signals are reconstructed and shipped to the first level of trigger at a rate of 40 MHz. This will provide a better precision of the calorimeter signals used by the trigger system and will allow the development of more complex trigger algorithms. Three different options are presently being investigated for the front-end electronic upgrade. Extensive test beam studies will determine which option will be selected. Field Programmable Gate Arrays (FPGAs) are extensively used for the logic functions of the off- and on-detector electronics. One hybrid demonstrator prototype module with the new calorimeter module electronics, but still compatible with the present system, may be inserted in ATLAS at the end of 2016.

  17. Rewaterproofing Chemical For Use With Silicones

    NASA Technical Reports Server (NTRS)

    Hill, William L.; Mitchell, Shirley M.; Massey, Howard S.

    1990-01-01

    Agent restores impermeability without degrading silicone adhesives and substructures. Dimethylethoxysilane (DMES) found to rewaterproof tiles and composite panels internally without harming materials that underlie them. Replaces hexamethyldisilazane (HMDS) as postmission rewaterproofing agent for tiles of thermal-protection system on Space Shuttle. Much of original waterproofing lost during rigors of launch and reentry. Potential terrestrial application includes composite materials in such structures as bridges and submarines.

  18. Design of a lighting system with high-power LEDs, large area electronics, and light management structure in the LUMENTILE European project

    NASA Astrophysics Data System (ADS)

    Carraro, L.; Simonetta, M.; Benetti, G.; Tramonte, A.; Capelli, G.; Benedetti, M.; Randone, E. M.; Ylisaukko-oja, A.; Keränen, K.; Facchinetti, T.; Giuliani, G.

    2017-02-01

    LUMENTILE (LUMinous ElectroNic TILE) is a project funded by the European Commission with the goal of developing a luminous tile with novel functionalities, capable of changing its color and interact with the user. Applications include interior/exterior tile for walls and floors covering, high-efficiency luminaries, and advertising under the form of giant video screens. High overall electrical efficiency of the tile is mandatory, as several millions of square meters are foreseen to be installed each year. Demand is for high uniformity of the illumination of the top tile surface, and for high optical extraction efficiency. These features are achieved by smart light management, using a new approach based on light guiding slab and spatially selective light extraction obtained using both diffusion and/or reflection from the top and bottom interfaces of the optical layer. Planar and edge configurations for the RGB LEDs are considered and compared. A square shape with side length from 20cm to 60cm is considered for the tiles. The electronic circuit layout must optimize the electrical efficiency, and be compatible with low-cost roll-to-roll production on flexible substrates. LED heat management is tackled by using dedicated solutions that allow operation in thermally harsh environment. An approach based on OLEDs has also been considered, still needing improvement on emitted power and ruggedness.

  19. Development of an improved coating for polybenzimidazole foam. [for space shuttle heat shields

    NASA Technical Reports Server (NTRS)

    Neuner, G. J.; Delano, C. B.

    1976-01-01

    An improved coating system was developed for Polybenzimidazole (PBI) foam to provide coating stability, ruggedness, moisture resistance, and to satisfy optical property requirements (alpha sub (s/epsilon) or = 0.4 and epsilon 0.8) for the space shuttle. The effort was performed in five tasks: Task 1 to establish material and process specifications for the PBI foam, and material specifications for the coatings; Task 2 to identify and evaluate promising coatings; Task 3 to establish mechanical and thermophysical properties of the tile components; Task 4 to determine by systems analysis the potential weight trade-offs associated with a coated PBI TPS; and Task 5 to establish a preliminary quality assurance program. The coated PBI tile was, through screening tests, determined to satisfy the design objectives with a reduced system weight over the baseline shuttle silica LRSI TPS. The developed tile provides a thermally stable, extremely rugged, low thermal conductivity insulator with a well characterized optical coating.

  20. Performance of an ablator for Space Shuttle inorbit repair in an arc-plasma airstream

    NASA Technical Reports Server (NTRS)

    Stewart, D. A.; Cuellar, M.; Flowers, O.

    1983-01-01

    An ablator patch material performed well in an arc plasma environment simulating nominal Earth entry conditions for the Space Shuttle. Ablation tests using vacuum molded cones provided data to optimize the formulation of a two part polymer system for application under space conditions. The blunt cones were made using a Teflon mold and a state of the art caulking gun. Char stability of formulations with various amounts of catalyst and diluent were investigated. The char was found to be unstable in formulations with low amounts of catalyst and high amounts of diluent. The best polymer system determined by these tests was evaluated using a half tile patch in a multiple High Temperature Reusable surface Insulation tile model. It was demonstrated that this ablator could be applied in a space environment using a state of the art caulking gun, would maintain the outer mold line of the thermal protection system during entry, and would keep the bond line temperature at the aluminum tile interface below the design limit.

  1. Tuning iteration space slicing based tiled multi-core code implementing Nussinov's RNA folding.

    PubMed

    Palkowski, Marek; Bielecki, Wlodzimierz

    2018-01-15

    RNA folding is an ongoing compute-intensive task of bioinformatics. Parallelization and improving code locality for this kind of algorithms is one of the most relevant areas in computational biology. Fortunately, RNA secondary structure approaches, such as Nussinov's recurrence, involve mathematical operations over affine control loops whose iteration space can be represented by the polyhedral model. This allows us to apply powerful polyhedral compilation techniques based on the transitive closure of dependence graphs to generate parallel tiled code implementing Nussinov's RNA folding. Such techniques are within the iteration space slicing framework - the transitive dependences are applied to the statement instances of interest to produce valid tiles. The main problem at generating parallel tiled code is defining a proper tile size and tile dimension which impact parallelism degree and code locality. To choose the best tile size and tile dimension, we first construct parallel parametric tiled code (parameters are variables defining tile size). With this purpose, we first generate two nonparametric tiled codes with different fixed tile sizes but with the same code structure and then derive a general affine model, which describes all integer factors available in expressions of those codes. Using this model and known integer factors present in the mentioned expressions (they define the left-hand side of the model), we find unknown integers in this model for each integer factor available in the same fixed tiled code position and replace in this code expressions, including integer factors, with those including parameters. Then we use this parallel parametric tiled code to implement the well-known tile size selection (TSS) technique, which allows us to discover in a given search space the best tile size and tile dimension maximizing target code performance. For a given search space, the presented approach allows us to choose the best tile size and tile dimension in parallel tiled code implementing Nussinov's RNA folding. Experimental results, received on modern Intel multi-core processors, demonstrate that this code outperforms known closely related implementations when the length of RNA strands is bigger than 2500.

  2. Automated Laser Cutting In Three Dimensions

    NASA Technical Reports Server (NTRS)

    Bird, Lisa T.; Yvanovich, Mark A.; Angell, Terry R.; Bishop, Patricia J.; Dai, Weimin; Dobbs, Robert D.; He, Mingli; Minardi, Antonio; Shelton, Bret A.

    1995-01-01

    Computer-controlled machine-tool system uses laser beam assisted by directed flow of air to cut refractory materials into complex three-dimensional shapes. Velocity, position, and angle of cut varied. In original application, materials in question were thermally insulating thick blankets and tiles used on space shuttle. System shapes tile to concave or convex contours and cuts beveled edges on blanket, without cutting through outer layer of quartz fabric part of blanket. For safety, system entirely enclosed to prevent escape of laser energy. No dust generated during cutting operation - all material vaporized; larger solid chips dislodged from workpiece easily removed later.

  3. A Survey of Collective Intelligence

    NASA Technical Reports Server (NTRS)

    Wolpert, David H.; Tumer, Kagan

    1999-01-01

    This chapter presents the science of "COllective INtelligence" (COIN). A COIN is a large multi-agent systems where: i) the agents each run reinforcement learning (RL) algorithms; ii) there is little to no centralized communication or control; iii) there is a provided world utility function that, rates the possible histories of tile full system. Tile conventional approach to designing large distributed systems to optimize a world utility does not use agents running RL algorithms. Rather that approach begins with explicit modeling of the overall system's dynamics, followed by detailed hand-tuning of the interactions between the components to ensure that they "cooperate" as far as the world utility is concerned. This approach is labor-intensive, often results in highly non-robust systems, and usually results in design techniques that, have limited applicability. In contrast, with COINs we wish to solve the system design problems implicitly, via the 'adaptive' character of the RL algorithms of each of the agents. This COIN approach introduces an entirely new, profound design problem: Assuming the RL algorithms are able to achieve high rewards, what reward functions for the individual agents will, when pursued by those agents, result in high world utility? In other words, what reward functions will best ensure that we do not have phenomena like the tragedy of the commons, or Braess's paradox? Although still very young, the science of COINs has already resulted in successes in artificial domains, in particular in packet-routing, the leader-follower problem, and in variants of Arthur's "El Farol bar problem". It is expected that as it matures not only will COIN science expand greatly the range of tasks addressable by human engineers, but it will also provide much insight into already established scientific fields, such as economics, game theory, or population biology.

  4. Method for Molding Planar Billet of Thermally Insulative Material Into Predetermined Non-Planar Shape

    NASA Technical Reports Server (NTRS)

    Kolodziej, Paul (Inventor); Carroll, Joe A. (Inventor); Smith, Dane (Inventor)

    1998-01-01

    A method and apparatus is discussed for molding thermal protection system (TPS) tiles for spacecraft. The apparatus and method include a bottom mold member defining a mold surface shaped like a surface of the spacecraft, e.g., the nose cap of wing leading edge, sought to be thermally protected. A flat billet of TPS material is positioned over the periphery of the mold surface, and a hollow weight element that has a periphery configured like the periphery of the mold surface is positioned on the billet. The billet is then heated in accordance with a predetermined heating regime, and during the heating process the weight of the weight element causes the billet to deform to assume the shape of the mold surface. If desired, a TUFI coating is impregnated into the billet prior to heating, and the coating is sintered to the billet during heating. After heating, a composite matrix material, e.g., a graphite or fiberglass cloth which is impregnated with epoxy or polimide, is bonded to the now-shaped tile to support the tile. Silicone can then be impregnated into the now-formed tile to provide flexibility of the tile.

  5. Parametric Weight Comparison of Current and Proposed Thermal Protection System (TPS) Concepts

    NASA Technical Reports Server (NTRS)

    Myers, David E.; Martin, Carl J.; Blosser, Max L.

    1999-01-01

    A parametric weight assessment of advanced metallic panel, ceramic blanket, and ceramic tile thermal protection systems (TPS) was conducted using an implicit, one-dimensional (1 -D) thermal finite element sizing code. This sizing code contained models to ac- count for coatings, fasteners, adhesives, and strain isolation pads. Atmospheric entry heating profiles for two vehicles, the Access to Space (ATS) rocket-powered single-stage-to-orbit (SSTO) vehicle and a proposed Reusable Launch Vehicle (RLV), were used to ensure that the trends were not unique to a particular trajectory. Eight TPS concepts were compared for a range of applied heat loads and substructural heat capacities to identify general trends. This study found the blanket TPS concepts have the lightest weights over the majority of their applicable ranges, and current technology ceramic tiles and metallic TPS concepts have similar weights. A proposed, state-of-the-art metallic system which uses a higher temperature alloy and efficient multilayer insulation was predicted to be significantly lighter than the ceramic tile systems and approaches blanket TPS weights for higher integrated heat loads.

  6. On the stability of a quasicrystal and its crystalline approximant in a system of hard disks with a soft corona

    NASA Astrophysics Data System (ADS)

    Pattabhiraman, Harini; Gantapara, Anjan P.; Dijkstra, Marjolein

    2015-10-01

    Using computer simulations, we study the phase behavior of a model system of colloidal hard disks with a diameter σ and a soft corona of width 1.4σ. The particles interact with a hard core and a repulsive square-shoulder potential. We calculate the free energy of the random-tiling quasicrystal and its crystalline approximants using the Frenkel-Ladd method. We explicitly account for the configurational entropy associated with the number of distinct configurations of the random-tiling quasicrystal. We map out the phase diagram and find that the random tiling dodecagonal quasicrystal is stabilised by entropy at finite temperatures with respect to the crystalline approximants that we considered, and its stability region seems to extend to zero temperature as the energies of the defect-free quasicrystal and the crystalline approximants are equal within our statistical accuracy.

  7. Detail view of the vertical stabilizer of the Orbiter Discovery ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail view of the vertical stabilizer of the Orbiter Discovery looking at the two-piece rudder which is used to control the yaw position of orbiter on approach and landing in earth's atmosphere and upon landing the two-piece rudder splays open to both sides of the stabilizer to act as an air brake to help slow the craft to a stop. Note the thermal protection system components with the white Advanced Flexible Reusable Surface Insulation Blanket and the black High-temperature Reusable Surface Insulation tiles along the outer edges (HRSI tiles). The marks seen on the HRSI tiles are injection point marks and holes for the application of waterproofing material. This view was taken from a service platform in the Orbiter Processing Facility at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX

  8. Reliable and redundant FPGA based read-out design in the ATLAS TileCal Demonstrator

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Akerstedt, Henrik; Muschter, Steffen; Drake, Gary

    The Tile Calorimeter at ATLAS [1] is a hadron calorimeter based on steel plates and scintillating tiles read out by PMTs. The current read-out system uses standard ADCs and custom ASICs to digitize and temporarily store the data on the detector. However, only a subset of the data is actually read out to the counting room. The on-detector electronics will be replaced around 2023. To achieve the required reliability the upgraded system will be highly redundant. Here the ASICs will be replaced with Kintex-7 FPGAs from Xilinx. This, in addition to the use of multiple 10 Gbps optical read-out links,more » will allow a full read-out of all detector data. Due to the higher radiation levels expected when the beam luminosity is increased, opportunities for repairs will be less frequent. The circuitry and firmware must therefore be designed for sufficiently high reliability using redundancy and radiation tolerant components. Within a year, a hybrid demonstrator including the new readout system will be installed in one slice of the ATLAS Tile Calorimeter. This will allow the proposed upgrade to be thoroughly evaluated well before the planned 2023 deployment in all slices, especially with regard to long term reliability. Different firmware strategies alongside with their integration in the demonstrator are presented in the context of high reliability protection against hardware malfunction and radiation induced errors.« less

  9. Tile Patterns with LOGO--Part III: Tile Patterns from Mult Tiles Using Logo.

    ERIC Educational Resources Information Center

    Clason, Robert G.

    1991-01-01

    A mult tile is a set of polygons each of which can be dissected into smaller polygons similar to the original set of polygons. Using a recursive LOGO method that requires solutions to various geometry and trigonometry problems, dissections of mult tiles are carried out repeatedly to produce tile patterns. (MDH)

  10. Military Curriculum Materials for Vocational and Technical Education. Builders School, Ceramic Tile Setting 3-9.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. National Center for Research in Vocational Education.

    This course, for individualized or group instruction on ceramic tile setting, was developed from military sources for use in vocational education. The course provides students with skills in mortar preparation, surface preparation, tile layout planning, tile setting, tile cutting, and the grouting of tile joints. Both theory and shop assignments…

  11. A new simple tiling, with unusual properties, by a polyhedron with 14 faces.

    PubMed

    Gabbrielli, Ruggero; O'Keeffe, Michael

    2008-05-01

    A monotypic simple tiling by a 14-face polyhedron that does not admit an isohedral tiling is described. The tiling is triclinic and contains four distinct, but combinatorially equivalent, kinds of tile.

  12. Fractal analysis of mandibular trabecular bone: optimal tile sizes for the tile counting method.

    PubMed

    Huh, Kyung-Hoe; Baik, Jee-Seon; Yi, Won-Jin; Heo, Min-Suk; Lee, Sam-Sun; Choi, Soon-Chul; Lee, Sun-Bok; Lee, Seung-Pyo

    2011-06-01

    This study was performed to determine the optimal tile size for the fractal dimension of the mandibular trabecular bone using a tile counting method. Digital intraoral radiographic images were obtained at the mandibular angle, molar, premolar, and incisor regions of 29 human dry mandibles. After preprocessing, the parameters representing morphometric characteristics of the trabecular bone were calculated. The fractal dimensions of the processed images were analyzed in various tile sizes by the tile counting method. The optimal range of tile size was 0.132 mm to 0.396 mm for the fractal dimension using the tile counting method. The sizes were closely related to the morphometric parameters. The fractal dimension of mandibular trabecular bone, as calculated with the tile counting method, can be best characterized with a range of tile sizes from 0.132 to 0.396 mm.

  13. Fractal analysis of mandibular trabecular bone: optimal tile sizes for the tile counting method

    PubMed Central

    Huh, Kyung-Hoe; Baik, Jee-Seon; Heo, Min-Suk; Lee, Sam-Sun; Choi, Soon-Chul; Lee, Sun-Bok; Lee, Seung-Pyo

    2011-01-01

    Purpose This study was performed to determine the optimal tile size for the fractal dimension of the mandibular trabecular bone using a tile counting method. Materials and Methods Digital intraoral radiographic images were obtained at the mandibular angle, molar, premolar, and incisor regions of 29 human dry mandibles. After preprocessing, the parameters representing morphometric characteristics of the trabecular bone were calculated. The fractal dimensions of the processed images were analyzed in various tile sizes by the tile counting method. Results The optimal range of tile size was 0.132 mm to 0.396 mm for the fractal dimension using the tile counting method. The sizes were closely related to the morphometric parameters. Conclusion The fractal dimension of mandibular trabecular bone, as calculated with the tile counting method, can be best characterized with a range of tile sizes from 0.132 to 0.396 mm. PMID:21977478

  14. Microwave and Millimeter Wave Testing for the Inspection of the Space Shuttle Spray on Foam Insulations (SOFI) and the Acreage Heat Tiles

    NASA Technical Reports Server (NTRS)

    Zoughi, R.; Kharkovsky, S.; Hepburn, F. L.

    2005-01-01

    The utility of microwave and millimeter wave nondestructive testing and evaluation (NDT&E) methods, for testing the Space Shuttle's external he1 tank spray on foam insulation (SOFI) and the acreage heat tiles has been investigated during the past two years. Millimeter wave NDE techniques are capable of producing internal images of SOFI. This paper presents the results of testing several diverse panels with embedded voids and debonds at millimeter wave frequencies. Additionally, the results of testing a set of heat tiles are also presented. Finally, the attributes of these methods as well as the advantageous features associated with these systems are also provided.

  15. Water absorption and desorption in shuttle ablator and insulation materials

    NASA Technical Reports Server (NTRS)

    Whitaker, A. F.; Smith, C. F.; Wooden, V. A.; Cothren, B. E.; Gregory, H.

    1982-01-01

    Shuttle systems ablator and insulation materials underwent water soak with subsequent water desorption in vacuum. Water accumulation in these materials after a soak for 24 hours ranged from +1.1% for orbiter tile to +161% for solid rocket booster MSA-1. After 1 minute in vacuum, water retention ranged from none in the orbiter tile to +70% for solid rocket booster cork.

  16. 41. West tile gauge on south pier. Each square tile ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    41. West tile gauge on south pier. Each square tile is 4' in size. Bottom number scale of west tile - Duluth Ship Canal, South Pier, North end of Minnesota Point & Canal Park, Duluth, St. Louis County, MN

  17. 48. East tile gauge on south pier. Each square tile ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    48. East tile gauge on south pier. Each square tile is 4' in size. Lower section of tile cross only - Duluth Ship Canal, South Pier, North end of Minnesota Point & Canal Park, Duluth, St. Louis County, MN

  18. Nutrient Concentrations and Stable Isotopes of Runoff from a Midwest Tile-Drained Corn Field

    NASA Astrophysics Data System (ADS)

    Wilkins, B. P.; Woo, D.; Li, J.; Michalski, G. M.; Kumar, P.; Conroy, J. L.; Keefer, D. A.; Keefer, L. L.; Hodson, T. O.

    2017-12-01

    Tile drains are a common crop drainage device used in Midwest agroecosystems. While efficient at drainage, the tiles provide a quick path for nutrient runoff, reducing the time available for microbes to use nutrients (e.g., NO3- and PO43-) and reduce export to riverine systems. Thus, understanding the effects of tile drains on nutrient runoff is critical to achieve nutrient reduction goals. Here we present isotopic and concentration data collected from tile drain runoff of a corn field located near Monticello, IL. Tile flow samples were measured for anion concentrations and stable isotopes of H2O and NO3-, while precipitation was measured for dual isotopes of H2O. Results demonstrate early tile flow from rain events have a low Cl- concentration (<20ppm) with water isotopic values reflecting precipitation, indicating preferential flow (>60% contribution) in the beginning of the hydrograph. As flow continues H2O isotopic values reflect pre-event water (ground and soil water), and Cl- concentrations increase representing a greater influence by matrix flow (60-90% contribution). Nitrate concentrations change dramatically, especially during the growing season, and do not follow a similar trend as the conservative Cl-, often decreasing days before, which represents missing nitrate in the upper surface portion of the soil. Nitrate isotopic data shows significant changes in 15N (4‰) and 18O (4‰) during individual hydrological events, representing that in addition to plant uptake and leaching, considerate NO3- is lost through denitrification. It is notable, that throughout the season d15N and d18O of nitrate change significantly representing that seasonally, substantial denitrification occurs.

  19. 40. West tile gauge on south pier. Each square tile ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    40. West tile gauge on south pier. Each square tile is 4' in size. Bottom right hand corner of west tile - Duluth Ship Canal, South Pier, North end of Minnesota Point & Canal Park, Duluth, St. Louis County, MN

  20. 39. West tile gauge on south pier. Each square tile ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    39. West tile gauge on south pier. Each square tile is 4' in size. Bottom left hand corner of west tile - Duluth Ship Canal, South Pier, North end of Minnesota Point & Canal Park, Duluth, St. Louis County, MN

  1. IIPImage: Large-image visualization

    NASA Astrophysics Data System (ADS)

    Pillay, Ruven

    2014-08-01

    IIPImage is an advanced high-performance feature-rich image server system that enables online access to full resolution floating point (as well as other bit depth) images at terabyte scales. Paired with the VisiOmatic (ascl:1408.010) celestial image viewer, the system can comfortably handle gigapixel size images as well as advanced image features such as both 8, 16 and 32 bit depths, CIELAB colorimetric images and scientific imagery such as multispectral images. Streaming is tile-based, which enables viewing, navigating and zooming in real-time around gigapixel size images. Source images can be in either TIFF or JPEG2000 format. Whole images or regions within images can also be rapidly and dynamically resized and exported by the server from a single source image without the need to store multiple files in various sizes.

  2. The research of Raman spectra measurement system based on tiled-grating monochromator

    NASA Astrophysics Data System (ADS)

    Liu, Li-na; Zhang, Yin-chao; Chen, Si-ying; Chen, He; Guo, Pan; Wang, Yuan

    2013-09-01

    A set of Raman spectrum measurement system, essentially a Raman spectrometer, has been independently designed and accomplished by our research group. This system adopts tiled-grating structure, namely two 50mm × 50mm holographic gratings are tiled to form a big spectral grating. It not only improves the resolution but also reduces the cost. This article outlines the Raman spectroscopy system's composition structure and performance parameters. Then corresponding resolutions of the instrument under different criterions are deduced through experiments and data fitting. The result shows that the system's minimum resolution is up to 0.02nm, equivalent to 0.5cm-1 wavenumber under Rayleigh criterion; and it will be up to 0.007nm, equivalent to 0.19cm-1 wavenumber under Sparrow criterion. Then Raman spectra of CCl4 and alcohol have been obtained by the spectrometer, which agreed with the standard spectrum respectively very well. Finally, we measured the spectra of the alcohol solutions with different concentrations and extracted the intensity of characteristic peaks from smoothed spectra. Linear fitting between intensity of characteristic peaks and alcohol solution concentrations has been made. And the linear correlation coefficient is 0.96.

  3. Users guide: Steady-state aerodynamic-loads program for shuttle TPS tiles

    NASA Technical Reports Server (NTRS)

    Kerr, P. A.; Petley, D. H.

    1984-01-01

    A user's guide for the computer program that calculates the steady-state aerodynamic loads on the Shuttle thermal-protection tiles is presented. The main element in the program is the MITAS-II, Martin Marietta Interactive Thermal Analysis System. The MITAS-II is used to calculate the mass flow in a nine-tile model designed to simulate conditions duing a Shuttle flight. The procedures used to execute the program using the MITAS-II software are described. A list of the necessry software and data files along with a brief description of their functions is given. The format of the data file containing the surface pressure data is specified. The interpolation techniques used to calculate the pressure profile over the tile matrix are briefly described. In addition, the output from a sample run is explained. The actual output and the procedure file used to execute the program at NASA Langley Research Center on a CDC CYBER-175 are provided in the appendices.

  4. Thermal fatigue testing of a diffusion-bonded beryllium divertor mock-up under ITER-relevant conditions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Youchison, D.L.; Watson, R.D.; McDonald, J.M.

    Thermal response and thermal fatigue tests of four 5-mm-thick beryllium tiles on a Russian Federation International Thermonuclear Experimental Reactor (ITER)-relevant divertor mock-up were completed on the electron beam test system at Sandia National Laboratories. Thermal response tests were performed on the tiles to an absorbed heat flux of 5 MW/m{sup 2} and surface temperatures near 300{degree}C using 1.4 MPa water at 5 m/s flow velocity and an inlet temperature of 8 to 15{degree}C. One tile was exposed to incrementally increasing heat fluxes up to 9.5 MW/m{sup 2} and surface temperatures up to 690{degree}C before debonding at 10MW/m{sup 2}. A secondmore » tile debonded in 25 to 30 cycles at <0.5 MW/m{sup 2}. However, a third tile debonded after 9200 thermal fatigue cycles at 5 MW/m{sup 2}, while another debonded after 6800 cycles. Posttest surface analysis indicated that fatigue failure occurred in the intermetallic layers between the beryllium and copper. No fatigue cracking of the bulk beryllium was observed. It appears that microcracks growing at the diffusion bond produced the observed gradual temperature increases during thermal cycling. These experiments indicate that diffusion-bonded beryllium tiles can survive several thousand thermal cycles under ITER-relevant conditions. However, the reliability of the diffusion-bonded joint remains a serious issue. 17 refs., 25 figs., 6 tabs.« less

  5. Hardware interface for isolation of vibrations in flexible manipulators: Development and applications

    NASA Technical Reports Server (NTRS)

    Manouchehri, Davoud; Lindsay, Thomas; Ghosh, David

    1994-01-01

    NASA's Langley Research Center (LaRC) is addressing the problem of isolating the vibrations of the Shuttle remote manipulator system (RMS) from its end-effector and/or payload by modeling an RMS flat-floor simulator with a dynamic payload. Analysis of the model can lead to control techniques that will improve the speed, accuracy, and safety of the RMS in capturing satellites and eventually facilitate berthing with the space station. Rockwell International Corporation, also involved in vibration isolation, has developed a hardware interface unit to isolate the end-effector from the vibrations of an arm on a Shuttle robotic tile processing system (RTPS). To apply the RTPS isolation techniques to long-reach arms like the RMS, engineers have modeled the dynamics of the hardware interface unit with simulation software. By integrating the Rockwell interface model with the NASA LaRC RMS simulator model, investigators can study the use of a hardware interface to isolate dynamic payloads from the RMS. The interface unit uses both active and passive compliance and damping for vibration isolation. Thus equipped, the RMS could be used as a telemanipulator with control characteristics for capture and berthing operations. The hardware interface also has applications in industry.

  6. Tony Rollins fashions a new tile for the Space Shuttle orbiter

    NASA Technical Reports Server (NTRS)

    1998-01-01

    In the Tile Fabrication Shop, Tony Rollins, with United Space Alliance, holds down a curtain while making a test sample of tile on a block 5-axis computerized numerical control milling machine. About 70 percent of a Space Shuttle orbiter's external surface is shielded from heat by a network of more than 24,000 tiles formed from a silica fiber compound. They are known as High-Temperature Reusable Surface Insulation (HRSI) tiles and Low-Temperature Reusable Surface Insulation (LRSI) tiles. Most HRSI tiles are 6 inches square, but may be as large as 12 inches in some areas, and 1 to 5 inches thick. LRSI tiles are generally 8 inches square, ranging from 0.2- to 1-inch thick. More advanced materials such as Flexible Insulation Blankets have replaced tiles on some upper surfaces of the orbiter.

  7. Ceramic tile expansion engine housing

    DOEpatents

    Myers, Blake

    1995-01-01

    An expandable ceramic tile housing for a high temperature engine is disclosed wherein each tile is independently supported in place in an interlocking matrix by retention mechanisms which mechanically couple the individual ceramic tiles to an outer metal support housing while maintaining thermal isolation of the metal housing from the ceramic tiles. The ceramic tiles are formed with either an octagonal front face portion and a square shank portion or a square front face portion with an octagonal shank portion. The length of the sides of the octagonal front face portion on one tile is equal to the length of the sides of the square front face portion of adjoining tiles to permit formation of an interlocking matrix. Fibrous ceramic sealing material may be placed between radial and tangential facing surfaces of adjacent tiles to limit radial gas flow therebetween. Labyrinth-sealed pressure-controlled compartments may be established between the tile housing and the outer metal support housing to control radial gas flow.

  8. Ceramic tile expansion engine housing

    DOEpatents

    Myers, B.

    1995-04-11

    An expandable ceramic tile housing for a high temperature engine is disclosed wherein each tile is independently supported in place in an interlocking matrix by retention mechanisms which mechanically couple the individual ceramic tiles to an outer metal support housing while maintaining thermal isolation of the metal housing from the ceramic tiles. The ceramic tiles are formed with either an octagonal front face portion and a square shank portion or a square front face portion with an octagonal shank portion. The length of the sides of the octagonal front face portion on one tile is equal to the length of the sides of the square front face portion of adjoining tiles to permit formation of an interlocking matrix. Fibrous ceramic sealing material may be placed between radial and tangential facing surfaces of adjacent tiles to limit radial gas flow there between. Labyrinth-sealed pressure-controlled compartments may be established between the tile housing and the outer metal support housing to control radial gas flow. 8 figures.

  9. Signatures of chaos in the Brillouin zone.

    PubMed

    Barr, Aaron; Barr, Ariel; Porter, Max D; Reichl, Linda E

    2017-10-01

    When the classical dynamics of a particle in a finite two-dimensional billiard undergoes a transition to chaos, the quantum dynamics of the particle also shows manifestations of chaos in the form of scarring of wave functions and changes in energy level spacing distributions. If we "tile" an infinite plane with such billiards, we find that the Bloch states on the lattice undergo avoided crossings, energy level spacing statistics change from Poisson-like to Wigner-like, and energy sheets of the Brillouin zone begin to "mix" as the classical dynamics of the billiard changes from regular to chaotic behavior.

  10. Acid emissions monitoring needs in ceramic tile industry: challenges derived from new policy trends

    NASA Astrophysics Data System (ADS)

    Celades, Irina; Gomar, Salvador; Romero, Fernando; Chauhan, Amisha; Delpech, Bertrand; Jouhara, Hussam

    2017-11-01

    The emission of acid compounds during the manufacture of ceramic tiles is strongly related to the presence of precursors in the raw materials and/or fuels used, with some exceptions such as the production of thermal NOX. The stages with the potential to produce significant emissions of these compounds have been identified as the suspension spray drying and tile firing stages. The monitoring of emission levels of acid pollutants in these stages has turned in a great importance issue from a regulatory and industrial aspect. The DREAM project (https://www.spire2030.eu/dream) will tackle the regulation of acidic emissions focusing in the firing stage. The initial stages of the project have made it possible to identify the design requirements for the monitoring system. This will allow the control of acid pollutants emissions and other key parameters such as pressure, flow, temperature and humidity. One of the tasks developed has been the review and compilation of current emissions monitoring systems detailing technical specifications such as: position (in situ or extractive), measurement principle and frequency. The future policy trends in air pollution are encouraging the continuous monitoring across the European industry. The present document assesses the advantages regarding environmental impact control, highlighting the main challenges for the ceramic tile industry.

  11. KENNEDY SPACE CENTER, FLA. - On a tour of the Tile Shop, members of the Stafford-Covey Return to Flight Task Group (SCTG) learn about PU-tiles, part of an orbiter’s Thermal Protection System. At left is Martin Wilson, with United Space Alliance. Others (left to right) around the table are James Adamson, Dr. Kathryn Clark, William Wegner, Richard Covey and Joe Engle. Covey, former Space Shuttle commander, is co-chair of the SCTG, along with Thomas P. Stafford, Apollo commander. Chartered by NASA Administrator Sean O’Keefe, the task group will perform an independent assessment of NASA’s implementation of the final recommendations by the Columbia Accident Investigation Board.

    NASA Image and Video Library

    2003-08-06

    KENNEDY SPACE CENTER, FLA. - On a tour of the Tile Shop, members of the Stafford-Covey Return to Flight Task Group (SCTG) learn about PU-tiles, part of an orbiter’s Thermal Protection System. At left is Martin Wilson, with United Space Alliance. Others (left to right) around the table are James Adamson, Dr. Kathryn Clark, William Wegner, Richard Covey and Joe Engle. Covey, former Space Shuttle commander, is co-chair of the SCTG, along with Thomas P. Stafford, Apollo commander. Chartered by NASA Administrator Sean O’Keefe, the task group will perform an independent assessment of NASA’s implementation of the final recommendations by the Columbia Accident Investigation Board.

  12. Performance of the ATLAS Hadronic Tile Calorimeter in Run-2 and its Upgrade for the High Luminosity LHC

    NASA Astrophysics Data System (ADS)

    Solovyanov, Oleg

    2017-10-01

    The Tile Calorimeter (TileCal) of the ATLAS experiment at the LHC is the central hadronic calorimeter designed for energy reconstruction of hadrons, jets, tauparticles and missing transverse energy. TileCal is a scintillator-steel sampling calorimeter and it covers the region of pseudo-rapidity up to 1.7, with almost 10000 channels measuring energies ranging from ˜30 MeV to ˜2 TeV. Each stage of the signal production, from scintillation light to the signal reconstruction, is monitored and calibrated. The performance of the Tile calorimeter has been studied in-situ employing cosmic ray muons and a large sample of proton-proton collisions, acquired during the operations of the LHC. Prompt isolated muons of high momentum from electroweak bosons decays are employed to study the energy response of the calorimeter at the electromagnetic scale. The calorimeter response to hadronic particles is evaluated with a sample of isolated hadrons. The modelling of the response by the Monte Carlo simulation is discussed. The calorimeter timing calibration and resolutions are studied with a sample of multijets events. Results on the calorimeter operation and performance are presented, including the calibration, stability, absolute energy scale, uniformity and time resolution. TileCal performance satisfies the design requirements and has provided an essential contribution to physics results in ATLAS. The Large Hadron Collider (LHC) has envisaged a series of upgrades towards a High Luminosity LHC (HL-LHC), delivering five times the LHC nominal instantaneous luminosity. The ATLAS Phase II upgrade, in 2024, will accommodate the detector and data acquisition system for the HL-LHC. In particular, the Tile Calorimeter will undergo a major replacement of its on- and off-detector electronics. All signals will be digitised and then transferred directly to the off-detector electronics, where the signals will be reconstructed, stored, and sent to the first level of trigger at a rate of 40 MHz. This will provide better precision for the calorimeter signals used by the trigger system and will allow the development of more complex trigger algorithms. Changes to the electronics will also contribute to the reliability and redundancy of the system. Three different front-end options are presently being investigated for the upgrade. Results of extensive laboratory tests and with beams of the three options will be presented, as well as the latest results on the development of the power distribution and the off-detector electronics.

  13. Closeup of F-15B Flight Test Fixture (FTF) with X-33 Thermal Protection Systems (TPS)

    NASA Technical Reports Server (NTRS)

    1998-01-01

    A close up of the Flight Test Fixture II, mounted on the underside of the F-15B Aerodynamic Flight Facility aircraft. The Thermal Protection System (TPS)samples, which included metallic Inconel tiles, soft Advanced Flexible Reusable Surface Insulation tiles, and sealing materials, were attached to the forward-left side position of the test fixture. In-flight video from the aircraft's on-board video system, as well as chase aircraft photos and video footage, documented the condition of the TPS during flights. Surface pressures over the TPS was measured by thermocouples contained in instrumentation 'islands,' to document shear and shock loads.

  14. Closeup of F-15B Flight Test Fixture (FTF) with X-33 Thermal Protection Systems (TPS)

    NASA Image and Video Library

    1998-05-14

    A close up of the Flight Test Fixture II, mounted on the underside of the F-15B Aerodynamic Flight Facility aircraft. The Thermal Protection System (TPS) samples, which included metallic Inconel tiles, soft Advanced Flexible Reusable Surface Insulation tiles, and sealing materials, were attached to the forward-left side position of the test fixture. In-flight video from the aircraft's on-board video system, as well as chase aircraft photos and video footage, documented the condition of the TPS during flights. Surface pressures over the TPS was measured by thermocouples contained in instrumentation "islands," to document shear and shock loads.

  15. Modeling of ultrasonic and terahertz radiations in defective tiles for condition monitoring of thermal protection systems

    NASA Astrophysics Data System (ADS)

    Kabiri Rahani, Ehsan

    Condition based monitoring of Thermal Protection Systems (TPS) is necessary for safe operations of space shuttles when quick turn-around time is desired. In the current research Terahertz radiation (T-ray) has been used to detect mechanical and heat induced damages in TPS tiles. Voids and cracks inside the foam tile are denoted as mechanical damage while property changes due to long and short term exposures of tiles to high heat are denoted as heat induced damage. Ultrasonic waves cannot detect cracks and voids inside the tile because the tile material (silica foam) has high attenuation for ultrasonic energy. Instead, electromagnetic terahertz radiation can easily penetrate into the foam material and detect the internal voids although this electromagnetic radiation finds it difficult to detect delaminations between the foam tile and the substrate plate. Thus these two technologies are complementary to each other for TPS inspection. Ultrasonic and T-ray field modeling in free and mounted tiles with different types of mechanical and thermal damages has been the focus of this research. Shortcomings and limitations of FEM method in modeling 3D problems especially at high-frequencies has been discussed and a newly developed semi-analytical technique called Distributed Point Source Method (DPSM) has been used for this purpose. A FORTRAN code called DPSM3D has been developed to model both ultrasonic and electromagnetic problems using the conventional DPSM method. This code is designed in a general form capable of modeling a variety of geometries. DPSM has been extended from ultrasonic applications to electromagnetic to model THz Gaussian beams, multilayered dielectrics and Gaussian beam-scatterer interaction problems. Since the conventional DPSM has some drawbacks, to overcome it two modification methods called G-DPSM and ESM have been proposed. The conventional DPSM in the past was only capable of solving time harmonic (frequency domain) problems. Time history was obtained by FFT (Fast Fourier Transform) algorithm. In this research DPSM has been extended to model DPSM transient problems without using FFT. This modified technique has been denoted as t-DPSM. Using DPSM, scattering of focused ultrasonic fields by single and multiple cavities in fluid & solid media is studied. It is investigated when two cavities in close proximity can be distinguished and when it is not possible. A comparison between the radiation forces generated by the ultrasonic energies reflected from two small cavities versus a single big cavity is also carried out.

  16. Tile Patterns with LOGO--Part II: Tile Patterns from Rep Tiles Using LOGO.

    ERIC Educational Resources Information Center

    Clason, Robert G.

    1991-01-01

    Described is a recursive LOGO method for dissecting polygons into congruent parts (rep tiles) similar to the original polygon, thereby producing unexpected patterns. A list of descriptions for such dissections is included along with suggestions for modifications that allow extended student explorations into tile patterns. (JJK)

  17. Switched Antenna Array Tile for Real-Time Microwave Imaging Aperture

    DTIC Science & Technology

    2016-06-26

    Switched Antenna Array Tile for Real -Time Microwave Imaging Aperture William F. Moulder, Janusz J. Majewski, Charles M. Coldwell, James D. Krieger...Fast Imaging Algorithm 10mm 250mm Switched Array Tile Fig. 1. Diagram of real -time imaging array, with fabricated antenna tile. except for antenna...formed. IV. CONCLUSIONS A switched array tile to be used in a real time imaging aperture has been presented. Design and realization of the tile were

  18. Filter arrays

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Page, Ralph H.; Doty, Patrick F.

    2017-08-01

    The various technologies presented herein relate to a tiled filter array that can be used in connection with performance of spatial sampling of optical signals. The filter array comprises filter tiles, wherein a first plurality of filter tiles are formed from a first material, the first material being configured such that only photons having wavelengths in a first wavelength band pass therethrough. A second plurality of filter tiles is formed from a second material, the second material being configured such that only photons having wavelengths in a second wavelength band pass therethrough. The first plurality of filter tiles and themore » second plurality of filter tiles can be interspersed to form the filter array comprising an alternating arrangement of first filter tiles and second filter tiles.« less

  19. Design and Applications of Rapid Image Tile Producing Software Based on Mosaic Dataset

    NASA Astrophysics Data System (ADS)

    Zha, Z.; Huang, W.; Wang, C.; Tang, D.; Zhu, L.

    2018-04-01

    Map tile technology is widely used in web geographic information services. How to efficiently produce map tiles is key technology for rapid service of images on web. In this paper, a rapid producing software for image tile data based on mosaic dataset is designed, meanwhile, the flow of tile producing is given. Key technologies such as cluster processing, map representation, tile checking, tile conversion and compression in memory are discussed. Accomplished by software development and tested by actual image data, the results show that this software has a high degree of automation, would be able to effectively reducing the number of IO and improve the tile producing efficiency. Moreover, the manual operations would be reduced significantly.

  20. Method and apparatus for displaying information

    NASA Technical Reports Server (NTRS)

    Huang, Sui (Inventor); Eichler, Gabriel (Inventor); Ingber, Donald E. (Inventor)

    2010-01-01

    A method for displaying large amounts of information. The method includes the steps of forming a spatial layout of tiles each corresponding to a representative reference element; mapping observed elements onto the spatial layout of tiles of representative reference elements; assigning a respective value to each respective tile of the spatial layout of the representative elements; and displaying an image of the spatial layout of tiles of representative elements. Each tile includes atomic attributes of representative elements. The invention also relates to an apparatus for displaying large amounts of information. The apparatus includes a tiler forming a spatial layout of tiles, each corresponding to a representative reference element; a comparator mapping observed elements onto said spatial layout of tiles of representative reference elements; an assigner assigning a respective value to each respective tile of said spatial layout of representative reference elements; and a display displaying an image of the spatial layout of tiles of representative reference elements.

  1. Healing assessment of tile sets for error tolerance in DNA self-assembly.

    PubMed

    Hashempour, M; Mashreghian Arani, Z; Lombardi, F

    2008-12-01

    An assessment of the effectiveness of healing for error tolerance in DNA self-assembly tile sets for algorithmic/nano-manufacturing applications is presented. Initially, the conditions for correct binding of a tile to an existing aggregate are analysed using a Markovian approach; based on this analysis, it is proved that correct aggregation (as identified with a so-called ideal tile set) is not always met for the existing tile sets for nano-manufacturing. A metric for assessing tile sets for healing by utilising punctures is proposed. Tile sets are investigated and assessed with respect to features such as error (mismatched tile) movement, punctured area and bond types. Subsequently, it is shown that the proposed metric can comprehensively assess the healing effectiveness of a puncture type for a tile set and its capability to attain error tolerance for the desired pattern. Extensive simulation results are provided.

  2. Environmental Setting of the Sugar Creek and Leary Weber Ditch Basins, Indiana, 2002-04

    USGS Publications Warehouse

    Lathrop, Timothy R.

    2006-01-01

    The U.S. Geological Survey operates streamflow-gaging stations at Sugar Creek at New Palestine and at Leary Weber Ditch at Mohawk within the study area. Mean daily streamflow for Sugar Creek is higher than streamflow at Leary Weber Ditch. Through most of its length, Sugar Creek is a gaining stream and base flow is supported by ground-water sources. At Leary Weber Ditch, there is little to no streamflow when tile drains are dry. Modifications to the natural hydrology of the study area include a large system of tile drains, the intersection of Sugar Creek by several major roads, and outflows from nearby wastewater-treatment plants. Leary Weber Ditch is affected only by tile drains.

  3. Efficient tiled calculation of over-10-gigapixel holograms using ray-wavefront conversion.

    PubMed

    Igarashi, Shunsuke; Nakamura, Tomoya; Matsushima, Kyoji; Yamaguchi, Masahiro

    2018-04-16

    In the calculation of large-scale computer-generated holograms, an approach called "tiling," which divides the hologram plane into small rectangles, is often employed due to limitations on computational memory. However, the total amount of computational complexity severely increases with the number of divisions. In this paper, we propose an efficient method for calculating tiled large-scale holograms using ray-wavefront conversion. In experiments, the effectiveness of the proposed method was verified by comparing its calculation cost with that using the previous method. Additionally, a hologram of 128K × 128K pixels was calculated and fabricated by a laser-lithography system, and a high-quality 105 mm × 105 mm 3D image including complicated reflection and translucency was optically reconstructed.

  4. Handedness in shearing auxetics creates rigid and compliant structures

    NASA Astrophysics Data System (ADS)

    Lipton, Jeffrey Ian; MacCurdy, Robert; Manchester, Zachary; Chin, Lillian; Cellucci, Daniel; Rus, Daniela

    2018-05-01

    In nature, repeated base units produce handed structures that selectively bond to make rigid or compliant materials. Auxetic tilings are scale-independent frameworks made from repeated unit cells that expand under tension. We discovered how to produce handedness in auxetic unit cells that shear as they expand by changing the symmetries and alignments of auxetic tilings. Using the symmetry and alignment rules that we developed, we made handed shearing auxetics that tile planes, cylinders, and spheres. By compositing the handed shearing auxetics in a manner inspired by keratin and collagen, we produce both compliant structures that expand while twisting and deployable structures that can rigidly lock. This work opens up new possibilities in designing chemical frameworks, medical devices like stents, robotic systems, and deployable engineering structures.

  5. [Therapeutic observation of subcutaneous pedicle screw-rod system with modified placement for Tile B pelvic fractures].

    PubMed

    Wu, Xiao-Tian; Chen, Nong; Pan, Fu-Gen; Liu, Zuo-Qing; He, Xiao-Jian

    2017-03-25

    To investigate the feasibility and therapeutic effect of subcutaneous pedicle screw-rod system with modified placement in treatment of Tile B pelvic fractures. From June 2014 to August 2015, 14 patients with Tile B pelvic fractures were treated by subcutaneous pedicle screw-rod system with modified placement in the anterior inferior iliac spine and pubic tubercle. There were 8 males and 6 females, aged from 23 to 65 years with an average of 42 years. Operative time, intraoperative blood loss, fracture healing and postoperative complication were observed and clinical effects were evaluated by Matta reduction standard and Majeed score. All patients were followed up from 8 to 15 months with an average of 10.5 months. Operative time was 25 to 45 min with an average of 32 min;intraoperative blood loss was 10 to 35 ml with an average of 18 ml. All fractures got primary healing and healed time was 9 to 14 weeks with an average of 12.5 weeks. No postoperative incision infection, internal fixation failure and ectopic ossification were found, 4 cases occurred unilateral lateral femoral cutaneous nerve injury and 1 case occurred unilateral femoral nerve paralysis, but all restored finally. According to Matta criteria, reduction was excellent in 7 cases, good in 5 cases, fair in 2 case. According to Majeed score system, the functional evaluation at last follow-up was excellent in 5 cases, good in 7 cases, fair in 2 cases with the average score of 81.50±8.05. Subcutaneous pedicle screw-rod system with modified placement in the anterior inferior iliac spine and pubic tubercle have advantages of strong reduction, less trauma and complications, and is a promising surgical method in the treatment of Tile B pelvic fractures.

  6. Electromagnetic shielding of thermal protection system for hypersonic vehicles

    NASA Astrophysics Data System (ADS)

    Albano, M.; Micheli, D.; Gradoni, G.; Morles, R. B.; Marchetti, M.; Moglie, F.; Mariani Primiani, V.

    2013-06-01

    The numerical simulation and the measurement of electromagnetic shielding at microwave frequencies of thermal protection system for hypersonic vehicles is presented using nested reverberation chamber. An example of a possible thermal protection system for a re-entry vehicle is presented. This system based on carbon material is electromagnetically characterized. The characterization takes into account not only the materials but also the final assembly configuration of the thermal protection system. The frequency range is 2-8 GHz. The results of measurements and simulations show that the microwave shielding effectiveness of carbon materials is above 60 dB for a single tile and that the tile inter-distance is able to downgrade the shielding effectiveness on the average to about 40 dB.

  7. Characterizing phosphorus dynamics in tile-drained agricultural fieldsof eastern Wisconsin

    USGS Publications Warehouse

    Madison, Allison; Ruark, Matthew; Stuntebeck, Todd D.; Komiskey, Matthew J.; Good, Laura W.; Drummy, Nancy; Cooley, Eric

    2014-01-01

    Artificial subsurface drainage provides an avenue for the rapid transfer of phosphorus (P) from agricultural fields to surface waters. This is of particular interest in eastern Wisconsin, where there is a concentrated population of dairy farms and high clay content soils prone to macropore development. Through collaboration with private landowners, surface and tile drainage was measured and analyzed for dissolved reactive P (DRP) and total P (TP) losses at four field sites in eastern Wisconsin between 2005 and 2009. These sites, which received frequent manure applications, represent a range of crop management practices which include: two chisel plowed corn fields (CP1, CP2), a no-till corn–soybean field (NT), and a grazed pasture (GP). Subsurface drainage was the dominant pathway of water loss at each site accounting for 66–96% of total water discharge. Average annual flow-weighted (FW) TP concentrations were 0.88, 0.57, 0.21, and 1.32 mg L−1 for sites CP1, CP2, NT, and GP, respectively. Low TP concentrations at the NT site were due to tile drain interception of groundwater flow where large volumes of tile drainage water diluted the FW-TP concentrations. Subsurface pathways contributed between 17% and 41% of the TP loss across sites. On a drainage event basis, total drainage explained between 36% and 72% of the event DRP loads across CP1, CP2, and GP; there was no relationship between event drainflow and event DRP load at the NT site. Manure applications did not consistently increase P concentrations in drainflow, but annual FW-P concentrations were greater in years receiving manure applications compared to years without manure application. Based on these field measures, P losses from tile drainage must be integrated into field level P budgets and P loss calculations on heavily manured soils, while also acknowledging the unique drainage patterns observed in eastern Wisconsin.

  8. Characterizing phosphorus dynamics in tile-drained agricultural fields of eastern Wisconsin

    NASA Astrophysics Data System (ADS)

    Madison, Allison M.; Ruark, Matthew D.; Stuntebeck, Todd D.; Komiskey, Matthew J.; Good, Lara W.; Drummy, Nancy; Cooley, Eric T.

    2014-11-01

    Artificial subsurface drainage provides an avenue for the rapid transfer of phosphorus (P) from agricultural fields to surface waters. This is of particular interest in eastern Wisconsin, where there is a concentrated population of dairy farms and high clay content soils prone to macropore development. Through collaboration with private landowners, surface and tile drainage was measured and analyzed for dissolved reactive P (DRP) and total P (TP) losses at four field sites in eastern Wisconsin between 2005 and 2009. These sites, which received frequent manure applications, represent a range of crop management practices which include: two chisel plowed corn fields (CP1, CP2), a no-till corn-soybean field (NT), and a grazed pasture (GP). Subsurface drainage was the dominant pathway of water loss at each site accounting for 66-96% of total water discharge. Average annual flow-weighted (FW) TP concentrations were 0.88, 0.57, 0.21, and 1.32 mg L-1 for sites CP1, CP2, NT, and GP, respectively. Low TP concentrations at the NT site were due to tile drain interception of groundwater flow where large volumes of tile drainage water diluted the FW-TP concentrations. Subsurface pathways contributed between 17% and 41% of the TP loss across sites. On a drainage event basis, total drainage explained between 36% and 72% of the event DRP loads across CP1, CP2, and GP; there was no relationship between event drainflow and event DRP load at the NT site. Manure applications did not consistently increase P concentrations in drainflow, but annual FW-P concentrations were greater in years receiving manure applications compared to years without manure application. Based on these field measures, P losses from tile drainage must be integrated into field level P budgets and P loss calculations on heavily manured soils, while also acknowledging the unique drainage patterns observed in eastern Wisconsin.

  9. KSC-98pc929

    NASA Image and Video Library

    1998-08-10

    In the Tile Fabrication Shop, Tony Rollins, with United Space Alliance, holds down a curtain while making a test sample of tile on a block 5-axis computerized numerical control milling machine. About 70 percent of a Space Shuttle orbiter’s external surface is shielded from heat by a network of more than 24,000 tiles formed from a silica fiber compound. They are known as High-Temperature Reusable Surface Insulation (HRSI) tiles and Low-Temperature Reusable Surface Insulation (LRSI) tiles. Most HRSI tiles are 6 inches square, but may be as large as 12 inches in some areas, and 1 to 5 inches thick. LRSI tiles are generally 8 inches square, ranging from 0.2to 1-inch thick. More advanced materials such as Flexible Insulation Blankets have replaced tiles on some upper surfaces of the orbiter

  10. Multiprocessor Z-Buffer Architecture for High-Speed, High Complexity Computer Image Generation.

    DTIC Science & Technology

    1983-12-01

    Oversampling 50 17. "Poking Through" Effects 51 18. Sampling Paths 52 19. Triangle Variables 54 20. Intelligent Tiling Algorithm 61 21. Tiler Functional Blocks...64 * 22. HSD Interface 65 23. Tiling Machine Setup 67 24. Tiling Machine 68 25. Tile Accumulate 69 26. A lx$ Sorting Machine 77 27. A 2x8 Sorting...Delay 227 87. Effect of Triangle Size on Tiler Throughput Rates 229 88. Tiling Machine Setup Stage Performance for Oversample Mode 234 89. Tiling

  11. Aerodynamic heat transfer to RSI tile surfaces and gap intersections. [Reusable Surface Insulation

    NASA Technical Reports Server (NTRS)

    Dunavant, J. C.; Throckmorton, D. A.

    1974-01-01

    Review of the results of aerothermal heating tests of a simulated reusable surface insulation (RSI) tile array, performed on the sidewall of a Mach-10 hypersonic tunnel. In particular, the heating characteristics of the tile array, such as they result from heating inside the tile-expansion-space providing gaps between individual tiles, are investigated. The results include the finding that heating on the upstream face of a tile is strongly affected by the interacting longitudinal gap flow.

  12. Military Petroleum Pipeline Systems

    DTIC Science & Technology

    1978-06-01

    miodes of trunsportu-"tion conforming to tile cross-section for International Orounizations for Standardizu-tion ( ISO ) und American National Standards...along the I 00-ni lie length of’ thle pipleline., Facli pumlp stat ion wouli operate at a inuxu~inai discharge pressuro of’ ISO lb/in2 delivering...difficult, it would be possible to install 4-Inch, ISO - and 300-pound-class valves and 6-Inch, 150-pound-class valves without tile aid of materials handling

  13. Evaluation of tile layer productivity in construction project

    NASA Astrophysics Data System (ADS)

    Aziz, Hamidi Abdul; Hassan, Siti Hafizan; Rosly, Noorsyalili; Ul-Saufie, Ahmad Zia

    2017-10-01

    Construction is a key sector of the national economy for countries all over the world. Until today, construction industries are still facing lots of problems concerning the low productivity, poor safety and insufficient quality. Labour productivity is one of the factors that will give impact to the quality of projects. This study is focusing on evaluating the tile layer productivity in the area of Seberang Perai, Penang. The objective of this study is to determine the relationship of age and experience of tile layers with their productivity and to evaluate the effect of nationality to tile layers productivity. Interview and site observation of tile layers has been conducted to obtain the data of age, experience and nationality of tile layers. Site observation is made to obtain the number of tiles installed for every tile layer for the duration of 1 hour, and the data were analysed by using Statistical Package for Social Science (IBM SPSS Statistic 23) software. As a result, there is a moderate linear relationship between age and experience of tile layers with their productivity. The age of 30 and the experience of 4 years give the highest productivity. It also can be concluded that the tile layers from Indonesia tend to have higher productivity compared to tile layers from Myanmar.

  14. Process-generated nanoparticles from ceramic tile sintering: Emissions, exposure and environmental release.

    PubMed

    Fonseca, A S; Maragkidou, A; Viana, M; Querol, X; Hämeri, K; de Francisco, I; Estepa, C; Borrell, C; Lennikov, V; de la Fuente, G F

    2016-09-15

    The ceramic industry is an industrial sector in need of significant process changes, which may benefit from innovative technologies such as laser sintering of ceramic tiles. Such innovations result in a considerable research gap within exposure assessment studies for process-generated ultrafine and nanoparticles. This study addresses this issue aiming to characterise particle formation, release mechanisms and their impact on personal exposure during a tile sintering activity in an industrial-scale pilot plant, as a follow-up of a previous study in a laboratory-scale plant. In addition, possible particle transformations in the exhaust system, the potential for particle release to the outdoor environment, and the effectiveness of the filtration system were also assessed. For this purpose, a tiered measurement strategy was conducted. The main findings evidence that nanoparticle emission patterns were strongly linked to temperature and tile chemical composition, and mainly independent of the laser treatment. Also, new particle formation (from gaseous precursors) events were detected, with nanoparticles <30nm in diameter being formed during the thermal treatment. In addition, ultrafine and nano-sized airborne particles were generated and emitted into workplace air during sintering process on a statistically significant level. These results evidence the risk of occupational exposure to ultrafine and nanoparticles during tile sintering activity since workers would be exposed to concentrations above the nano reference value (NRV; 4×10(4)cm(-3)), with 8-hour time weighted average concentrations in the range of 1.4×10(5)cm(-3) and 5.3×10(5)cm(-3). A potential risk for nanoparticle and ultrafine particle release to the environment was also identified, despite the fact that the efficiency of the filtration system was successfully tested and evidenced a >87% efficiency in particle number concentrations removal. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  15. Detail view of the leading and top edge of the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail view of the leading and top edge of the vertical stabilizer of the Orbiter Discovery showing the thermal protection system components with the white Advanced Flexible Reusable Surface Insulation (AFRSI) blanket and the black High-temperature Reusable Surface Insulation (HRSI) tiles along the outer edges. The marks seen on the HRSI tiles are injection point marks and holes for the application of waterproofing material. This view was taken from a service platform in the Orbiter Processing Facility at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX

  16. The challenging scales of the bird: Shuttle tile structural integrity

    NASA Technical Reports Server (NTRS)

    Schneider, W. C.; Miller, G. J.

    1985-01-01

    The principal design issues, tests, and analyses required to solve the tile integrity problem on the space shuttle orbiters are addressed. Proof testing of installed tiles is discussed along with an airflow test of special tiles. Orbiter windshield tiles are considered in terms of changes necessary to ensure acceptable margins of safety for flight.

  17. Thermal stress analysis of space shuttle orbiter wing skin panel and thermal protection system

    NASA Technical Reports Server (NTRS)

    Ko, William L.; Jenkins, Jerald M.

    1987-01-01

    Preflight thermal stress analysis of the space shuttle orbiter wing skin panel and the thermal protection system (TPS) was performed. The heated skin panel analyzed was rectangular in shape and contained a small square cool region at its center. The wing skin immediately outside the cool region was found to be close to the state of elastic instability in the chordwise direction based on the conservative temperature distribution. The wing skin was found to be quite stable in the spanwise direction. The potential wing skin thermal instability was not severe enough to tear apart the strain isolation pad (SIP) layer. Also, the preflight thermal stress analysis was performed on the TPS tile under the most severe temperature gradient during the simulated reentry heating. The tensile thermal stress induced in the TPS tile was found to be much lower than the tensile strength of the TPS material. The thermal bending of the TPS tile was not severe enough to cause tearing of the SIP layer.

  18. Multiyear nutrient removal performance of three constructed wetlands intercepting tile drain flows from grazed pastures.

    PubMed

    Tanner, Chris C; Sukias, James P S

    2011-01-01

    Subsurface tile drain flows can be a major s ource of nurient loss from agricultural landscapes. This study quantifies flows and nitrogen and phosphorus yields from tile drains at three intensively grazed dairy pasture sites over 3- to 5-yr periods and evaluates the capacity of constructed wetlands occupying 0.66 to 1.6% of the drained catchments too reduce nutrient loads. Continuous flow records are combined with automated flow-proportional sampling of nutrient concentrations to calculate tile drain nutrient yields and wetland mass removal rates. Annual drainage water yields rangedfrom 193 to 564 mm (16-51% of rainfall) at two rain-fed sites and from 827 to 853 mm (43-51% of rainfall + irrigation) at an irrigated site. Annually, the tile drains exported 14 to 109 kg ha(-1) of total N (TN), of which 58 to 90% was nitrate-N. Constructed wetlands intercepting these flows removed 30 to 369 gTN m(-2) (7-63%) of influent loadings annually. Seasonal percentage nitrate-N and TN removal were negatively associated with wetland N mass loadings. Wetland P removal was poor in all wetlands, with 12 to 115% more total P exported annually overall than received. Annually, the tile drains exported 0.12 to 1.38 kg ha of total P, of which 15 to 93% was dissolved reactive P. Additional measures are required to reduce these losses or provide supplementary P removal. Wetland N removal performance could be improved by modifying drainage systems to release flows more gradually and improving irrigation practices to reduce drainage losses.

  19. Flaw detection in a multi-material multi-layered composite: using fem and air-coupled ut

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Livings, R. A.; Dayal, V.; Barnard, D. J.

    Ceramic tiles are the main ingredient of a multi-layer multi-material composite being considered for the modernization of tank armors. The high stiffness, low attenuation, and precise dimensions of these uniform tiles make them remarkable resonators when driven to vibrate. This study is aimed at modeling the vibration modes of the tiles and the composite lay-up with finite element analysis and comparing the results with the resonance modes observed in air-coupled ultrasonic excitation of the tiles and armor samples. Defects in the tile, during manufacturing and/or after usage, are expected to change the resonance modes. The comparison of a pristine tile/lay-upmore » and a defective tile/lay-up will thus be a quantitative damage metric. The understanding of the vibration behavior of the tile, both by itself and in the composite lay-up, can provide useful guidance to the nondestructive evaluation of armor panels containing ceramic tiles.« less

  20. Self-Cleaning Ceramic Tiles Produced via Stable Coating of TiO₂ Nanoparticles.

    PubMed

    Shakeri, Amid; Yip, Darren; Badv, Maryam; Imani, Sara M; Sanjari, Mehdi; Didar, Tohid F

    2018-06-13

    The high photocatalytic power of TiO₂ nanoparticles has drawn great attention in environmental and medical applications. Coating surfaces with these particles enables us to benefit from self-cleaning properties and decomposition of pollutants. In this paper, two strategies have been introduced to coat ceramic tiles with TiO₂ nanoparticles, and the self-cleaning effect of the surfaces on degradation of an organic dye under ultraviolent (UV) exposure is investigated. In the first approach, a simple one-step heat treatment method is introduced for coating, and different parameters of the heat treatment process are examined. In the second method, TiO₂ nanoparticles are first aminosilanized using (3-Aminopropyl)triethoxysilane (APTES) treatment followed by their covalently attachment onto CO₂ plasma treated ceramic tiles via N -(3-Dimethylaminopropyl)- N ′-ethylcarbodiimide hydrochloride (EDC) and N -Hydroxysuccinimide (NHS) chemistry. We monitor TiO₂ nanoparticle sizes throughout the coating process using dynamic light scattering (DLS) and characterize developed surfaces using X-ray photoelectron spectroscopy (XPS). Moreover, hydrophilicity of the coated surfaces is quantified using a contact angle measurement. It is shown that applying a one-step heat treatment process with the optimum temperature of 200 °C for 5 h results in successful coating of nanoparticles and rapid degradation of dye in a short time. In the second strategy, the APTES treatment creates a stable covalent coating, while the photocatalytic capability of the particles is preserved. The results show that coated ceramic tiles are capable of fully degrading the added dyes under UV exposure in less than 24 h.

  1. Interlocking wettable ceramic tiles

    DOEpatents

    Tabereaux, Jr., Alton T.; Fredrickson, Guy L.; Groat, Eric; Mroz, Thomas; Ulicny, Alan; Walker, Mark F.

    2005-03-08

    An electrolytic cell for the reduction of aluminum having a layer of interlocking cathode tiles positioned on a cathode block. Each tile includes a main body and a vertical restraining member to prevent movement of the tiles away from the cathode block during operation of the cell. The anode of the electrolytic cell may be positioned about 1 inch from the interlocking cathode tiles.

  2. 9. Detail of "BMT lines" tile sign, and decorative tiles ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. Detail of "BMT lines" tile sign, and decorative tiles between center and east castellations of south facade. Looking north. - Stillwell Avenue Station, Intersection of Stillwell & Surf Avenues, Brooklyn, Kings County, NY

  3. Shuttle Technology for Earth Laboratories

    NASA Technical Reports Server (NTRS)

    1987-01-01

    Pyran System represents a major advancement in control of pyrolysis, the technology of subjecting organic material to selected temperatures to break them down into their component parts, and that the system offers capabilities unavailable. Pyran System is designed for rapid automated analysis of the composition of organic matter. It is capable of heating samples to 1,130 degrees fahrenheit with infrared heat at a precisely controlled atmosphere. In order to do this with the degree of control and repeatability desired, the developers of the Pyran system decided they would need a special type of material to insulate the heating chambers. They adopted the shuttle tiles for the difficult insulating job. The tiles provide superior insulating characteristics needed, and they can be readily cut and formed to fit the heating chambers.

  4. Modeling and Simulation of Ceramic Arrays to Improve Ballaistic Performance

    DTIC Science & Technology

    2013-11-01

    2219 , 2000 Tile gap is found to increase the DoP as compared to One Tile tiles The next step will be run simulations on narrower and wider gap sizes...experiments described in reference - ARL-TR- 2219 , 2000 □ Tile gap is found to increase the DoP as compared to One Tile tiles □ The next step will be run...L| Al m ^ s\\cr V^ 1 v^ □ Smoothed-particle hydrodynamics (SPH) used for all parts □ SPH size = 0.40-mm, totaling 278k

  5. Upland and in-stream controls on baseflow nutrient dynamics in tile-drained agroecosystem watersheds

    NASA Astrophysics Data System (ADS)

    Ford, William I.; King, Kevin; Williams, Mark R.

    2018-01-01

    In landscapes with low residence times (e.g., rivers and reservoirs), baseflow nutrient concentration dynamics during sensitive timeframes can contribute to deleterious environmental conditions downstream. This study assessed upland and in-stream controls on baseflow nutrient concentrations in a low-gradient, tile-drained agroecosystem watershed. We conducted time-series analysis using Empirical mode decomposition of seven decade-long nutrient concentration time-series in the agricultural Upper Big Walnut Creek watershed (Ohio, USA). Four tributaries of varying drainage areas and three main-stem sites were monitored, and nutrient grab samples were collected weekly from 2006 to 2016 and analyzed for dissolved reactive phosphorus (DRP), nitrate-nitrogen (NO3-N), total nitrogen (TN), and total phosphorus (TP). Statistically significant seasonal fluctuations were compared with seasonality of baseflow, watershed characteristics (e.g., tile-drain density), and in-stream water quality parameters (pH, DO, temperature). Findings point to statistically significant seasonality of all parameters with peak P concentrations in summer and peak N in late winter-early spring. Results suggest that upland processes exert strong control on DRP concentrations in the winter and spring months, while coupled upland and in-stream conditions control watershed baseflow DRP concentrations during summer and early fall. Conversely, upland flow sources driving streamflow exert strong control on baseflow NO3-N, and in-stream attenuation through transient and permanent pathways impacts the magnitude of removal. Regarding TN and TP, we found that TN was governed by NO3-N, while TP was governed by DRP in summer and fluvial erosion of P-rich benthic sediments during higher baseflow conditions. Findings of the study highlight the importance of coupled in-stream and upland management for mitigating eutrophic conditions during environmentally sensitive timeframes.

  6. Tackling the Four V's with NEXUS

    NASA Astrophysics Data System (ADS)

    Greguska, F. R., III; Gill, K. M.; Huang, T.; Jacob, J. C.; Quach, N.; Wilson, B. D.

    2016-12-01

    NASA's Earth Observing System Data and Information System (EOSDIS) reports that over 15 petabytes (PB) of Earth observing information are archived among the 12 NASA Distributed Active Archive Centers (DAACs); with more being archived daily. The upcoming Surface Water & Ocean Topography (SWOT) mission is expected to generate about 26 PB of data in 3 years. NEXUS is a state of the art deep data analytic program developed at the Jet Propulsion Laboratory with the goal of providing near real-time analytic capabilities for this vast trove of data. Rather than develop analytic services on traditional file archives, NEXUS organizes data into tiles in order to provide a platform for horizontal computing. To provide near real-time analytic solutions for missions such as SWOT, a highly scalable data ingestion solution is developed to quickly bring data into NEXUS. In order to accomplish this formidable challenge, the "Four V's" (Volume, Velocity, Veracity, and Variety) of Big Data must be considered. NEXUS consists of an ingestion subsystem that handles the Volume of data by utilizing a generic tiling strategy that subsets a given dataset into smaller tiles. These tiles are then indexed by a search engine and stored in a NoSQL database for fast retrieval. In addition to handling the Volume of data being indexed, the NEXUS ingestion subsystem is built for horizontal scalability in order to manage the Velocity of incoming data. As the load on the system increases, the components of the ingestion subsystem can be scaled to provide more capacity. During ingestion, NEXUS also takes a unique approach to the Veracity and Variety of Earth observing information being ingested. By allowing the processing and tiling mechanisms to be customized for each dataset, the NEXUS ingest system can discard erroneous or missing data as well as adapt to the many different data structures and file formats that can be found in satellite observation data. This talk will focus on the functionality and architecture of the data ingestion subsystem that is a part of the NEXUS software architecture and how it relates to the Four V's of Big Data.

  7. Architectures for Parafermionic Topological Matter in Two Dimensions

    NASA Astrophysics Data System (ADS)

    Burrello, Michele; van Heck, Bernard; Cobanera, Emilio

    2013-03-01

    Recent proposals exploit edge modes of fractional topological insulators (FTIs), induced superconducting pairing, and back-scattering to realize one-dimensional systems of parafermions. We extend these proposals to two dimensions and analyze the effect of the superconducting islands' charging energy on the parafermions they host. We focus on two two-dimensional architectures, the tile and stripe configurations, characterized by different distributions of FTIs and derive the associated parafermionic effective Hamiltonians. The tile model realizes the Z2 m toric code in low-order perturbation theory and hence possesses full topological quantum order. By exploiting dualities, we obtain the phase diagram and generalized order parameters for both the tile and stripe models of parafermions. This work was supported by the Dutch Science Foundation NWO/FOM and an ERC Advanced Investigator grant.

  8. Closeup view of the exterior of the starboard side of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Close-up view of the exterior of the starboard side of the forward fuselage of the Orbiter Discovery looking at the forward facing observation windows of the flight deck. Note the High-temperature Reusable Surface Insulation (HRSI) surrounding the window openings, the Low-temperature Reusable Surface Insulation (LRSI) immediately beyond the HRSI tiles and the Advanced Flexible Reusable Surface Insulation blankets just beyond the LRSI tiles. The holes in the tiles are injection points for the application of waterproofing material. The windows are composed of redundant pressure window panes of thermal glass. This image was taken from a service platform in the Orbiter Processing Facility at Kennedy Space Center - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX

  9. Covering the Plane with Rep-Tiles.

    ERIC Educational Resources Information Center

    Fosnaugh, Linda S.; Harrell, Marvin E.

    1996-01-01

    Presents an activity in which students use geometric figures, rep-tiles, to design a tile floor. Rep-tiles are geometric figures of which copies can fit together to form a larger similar figure. Includes reproducible student worksheet. (MKR)

  10. Flaw investigation in a multi-layered, multi-material composite: Using air-coupled ultrasonic resonance imaging

    NASA Astrophysics Data System (ADS)

    Livings, R. A.; Dayal, V.; Barnard, D. J.; Hsu, D. K.

    2012-05-01

    Ceramic tiles are the main ingredient of a multi-material, multi-layered composite being considered for the modernization of tank armors. The high stiffness, low attenuation, and precise dimensions of these uniform tiles make them remarkable resonators when driven to vibrate. Defects in the tile, during manufacture or after usage, are expected to change the resonance frequencies and resonance images of the tile. The comparison of the resonance frequencies and resonance images of a pristine tile/lay-up to a defective tile/lay-up will thus be a quantitative damage metric. By examining the vibrational behavior of these tiles and the composite lay-up with Finite Element Modeling and analytical plate vibration equations, the development of a new Nondestructive Evaluation technique is possible. This study examines the development of the Air-Coupled Ultrasonic Resonance Imaging technique as applied to a hexagonal ceramic tile and a multi-material, multi-layered composite.

  11. Real-time biscuit tile image segmentation method based on edge detection.

    PubMed

    Matić, Tomislav; Aleksi, Ivan; Hocenski, Željko; Kraus, Dieter

    2018-05-01

    In this paper we propose a novel real-time Biscuit Tile Segmentation (BTS) method for images from ceramic tile production line. BTS method is based on signal change detection and contour tracing with a main goal of separating tile pixels from background in images captured on the production line. Usually, human operators are visually inspecting and classifying produced ceramic tiles. Computer vision and image processing techniques can automate visual inspection process if they fulfill real-time requirements. Important step in this process is a real-time tile pixels segmentation. BTS method is implemented for parallel execution on a GPU device to satisfy the real-time constraints of tile production line. BTS method outperforms 2D threshold-based methods, 1D edge detection methods and contour-based methods. Proposed BTS method is in use in the biscuit tile production line. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  12. Validation of Land-Surface Mosaic Heterogeneity in the GEOS DAS

    NASA Technical Reports Server (NTRS)

    Bosilovich, Michael G.; Molod, Andrea; Houser, Paul R.; Schubert, Siegfried

    1999-01-01

    The Mosaic Land-surface Model (LSM) has been included into the current GEOS Data Assimilation System (DAS). The LSM uses a more advanced representation of physical processes than previous versions of the GEOS DAS, including the representation of sub-grid heterogeneity of the land-surface through the Mosaic approach. As a first approximation, Mosaic assumes that all similar surface types within a grid-cell can be lumped together as a single'tile'. Within one GCM grid-cell, there might be 1 - 5 different tiles or surface types. All tiles are subjected to the grid-scale forcing (radiation, air temperature and specific humidity, and precipitation), and the sub-grid variability is a function of the tile characteristics. In this paper, we validate the LSM sub-grid scale variability (tiles) using a variety of surface observing stations from the Southern Great Plains (SGP) site of the Atmospheric Radiation Measurement (ARM) Program. One of the primary goals of SGP ARM is to study the variability of atmospheric radiation within a G,CM grid-cell. Enough surface data has been collected by ARM to extend this goal to sub-grid variability of the land-surface energy and water budgets. The time period of this study is the Summer of 1998 (June I - September 1). The ARM site data consists of surface meteorology, energy flux (eddy correlation and bowen ratio), soil water observations spread over an area similar to the size of a G-CM grid-cell. Various ARM stations are described as wheat and alfalfa crops, pasture and range land. The LSM tiles considered at the grid-space (2 x 2.5) nearest the ARM site include, grassland, deciduous forests, bare soil and dwarf trees. Surface energy and water balances for each tile type are compared with observations. Furthermore, we will discuss the land-surface sub-grid variability of both the ARM observations and the DAS.

  13. Architectural Survey of Pence Elementary School, Fort Leonard Wood, Missouri

    DTIC Science & Technology

    2011-09-01

    classroom floors , replacement acoustical tile drop ceilings, both original pendent ceiling light fixtures and replacement light fixtures, replacement wood...fixed pane transoms above, original door hardware, acoustical tile drop-ceiling, asbestos tile floor , and a metal radiator cover (photos 38-40...119). The corridors have acoustical tile drop-ceilings, concrete block walls, and asbestos tile floors (photo 44). There are several push-pin cork

  14. Composite treatment of ceramic tile armor

    DOEpatents

    Hansen, James G. R. [Oak Ridge, TN; Frame, Barbara J [Oak Ridge, TN

    2010-12-14

    An improved ceramic tile armor has a core of boron nitride and a polymer matrix composite (PMC) facing of carbon fibers fused directly to the impact face of the tile. A polyethylene fiber composite backing and spall cover are preferred. The carbon fiber layers are cured directly onto the tile, not adhered using a separate adhesive so that they are integral with the tile, not a separate layer.

  15. Composite treatment of ceramic tile armor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hansen, James G. R.; Frame, Barbara J

    An improved ceramic tile armor has a core of boron nitride and a polymer matrix composite (PMC) facing of carbon fibers fused directly to the impact face of the tile. A polyethylene fiber composite backing and spall cover are preferred. The carbon fiber layers are cured directly onto the tile, not adhered using a separate adhesive so that they are integral with the tile, not a separate layer.

  16. Positive feedback fishery: Population consequences of `crab-tiling' on the green crab Carcinus maenas

    NASA Astrophysics Data System (ADS)

    Sheehan, E. V.; Thompson, R. C.; Coleman, R. A.; Attrill, M. J.

    2008-11-01

    Collection of marine invertebrates for use as fishing bait is a substantial activity in many parts of the world, often with unknown ecological consequences. As new fisheries develop, it is critical for environmental managers to have high quality ecological information regarding the potential impacts, in order to develop sound management strategies. Crab-tiling is a largely unregulated and un-researched fishery, which operates commercially in the south-west UK. The target species is the green crab Carcinus maenas. Those crabs which are pre-ecdysis and have a carapace width greater than 40 mm are collected to be sold to recreational anglers as bait. Collection involves laying artificial structures on intertidal sandflats and mudflats in estuaries. Crabs use these structures as refugia and are collected during low tide. However, the effect that this fishery has on populations of C. maenas is not known. The impact of crab-tiling on C. maenas population structure was determined by sampling crabs from tiled estuaries and non-tiled estuaries using baited drop-nets. A spatially and temporarily replicated, balanced design was used to compare crab abundance, sizes and sex ratios between estuaries. Typically, fisheries are associated with a reduction in the abundance of the target species. Crab-tiling, however, significantly increased C. maenas abundance. This was thought to be a result of the extra habitat in tiled estuaries, which probably provides protection from natural predators, such as birds and fish. Although crabs were more abundant in tiled estuaries than non-tiled estuaries, the overall percentage of reproductively active crabs in non-tiled estuaries was greater than in tiled estuaries. As with most exploited fisheries stocks, crabs in exploited (tiled) estuaries tended to be smaller, with a modal carapace width of 20-29 mm rather than 30-39 mm in non-tiled estuaries. The sex ratio of crabs however; was not significantly different between tiled and non-tiled estuaries. These results illustrate the potential to manage fished populations using habitat provision to mitigate the effects of fishing pressure.

  17. KSC-2012-1570

    NASA Image and Video Library

    2012-03-01

    CAPE CANAVERAL, Fla. -- John Livingston, a United Space Alliance engineer at NASA's Kennedy Space Center in Florida, describes the properties of the heat shield tiles that will be installed to the backshell of the Orion Multi-Purpose Crew Vehicle's Exploration Flight Test EFT-1 capsule. The tiles are being manufactured and inspected in Kennedy's Thermal Protection System Facility. EFT-1 will be used during Orion's first test flight in space. For more information, visit www.nasa.gov/orion. Photo credit: Frankie Martin

  18. PGAS in-memory data processing for the Processing Unit of the Upgraded Electronics of the Tile Calorimeter of the ATLAS Detector

    NASA Astrophysics Data System (ADS)

    Ohene-Kwofie, Daniel; Otoo, Ekow

    2015-10-01

    The ATLAS detector, operated at the Large Hadron Collider (LHC) records proton-proton collisions at CERN every 50ns resulting in a sustained data flow up to PB/s. The upgraded Tile Calorimeter of the ATLAS experiment will sustain about 5PB/s of digital throughput. These massive data rates require extremely fast data capture and processing. Although there has been a steady increase in the processing speed of CPU/GPGPU assembled for high performance computing, the rate of data input and output, even under parallel I/O, has not kept up with the general increase in computing speeds. The problem then is whether one can implement an I/O subsystem infrastructure capable of meeting the computational speeds of the advanced computing systems at the petascale and exascale level. We propose a system architecture that leverages the Partitioned Global Address Space (PGAS) model of computing to maintain an in-memory data-store for the Processing Unit (PU) of the upgraded electronics of the Tile Calorimeter which is proposed to be used as a high throughput general purpose co-processor to the sROD of the upgraded Tile Calorimeter. The physical memory of the PUs are aggregated into a large global logical address space using RDMA- capable interconnects such as PCI- Express to enhance data processing throughput.

  19. Nosql for Storage and Retrieval of Large LIDAR Data Collections

    NASA Astrophysics Data System (ADS)

    Boehm, J.; Liu, K.

    2015-08-01

    Developments in LiDAR technology over the past decades have made LiDAR to become a mature and widely accepted source of geospatial information. This in turn has led to an enormous growth in data volume. The central idea for a file-centric storage of LiDAR point clouds is the observation that large collections of LiDAR data are typically delivered as large collections of files, rather than single files of terabyte size. This split of the dataset, commonly referred to as tiling, was usually done to accommodate a specific processing pipeline. It makes therefore sense to preserve this split. A document oriented NoSQL database can easily emulate this data partitioning, by representing each tile (file) in a separate document. The document stores the metadata of the tile. The actual files are stored in a distributed file system emulated by the NoSQL database. We demonstrate the use of MongoDB a highly scalable document oriented NoSQL database for storing large LiDAR files. MongoDB like any NoSQL database allows for queries on the attributes of the document. As a specialty MongoDB also allows spatial queries. Hence we can perform spatial queries on the bounding boxes of the LiDAR tiles. Inserting and retrieving files on a cloud-based database is compared to native file system and cloud storage transfer speed.

  20. Light, Strong Insulating Tiles

    NASA Technical Reports Server (NTRS)

    Cordia, E.; Schirle, J.

    1987-01-01

    Improved lightweight insulating silica/aluminum borosilicate/silicon carbide tiles combine increased tensile strength with low thermal conductivity. Changes in composition substantially improve heat-insulating properties of silica-based refractory tile. Silicon carbide particles act as high-emissivity radiation scatterers in tile material.

  1. Tile Patterns with Logo--Part I: Laying Tile with Logo.

    ERIC Educational Resources Information Center

    Clason, Robert G.

    1990-01-01

    Described is a method for drawing periodic tile patterns using LOGO. Squares, triangles, hexagons, shape filling, and random tile laying are included. These activities incorporate problem solving, programing methods, and the geometry of angles and polygons. (KR)

  2. The Intricate Art of Persian Tiles: An Interview with Jafar Mogadam.

    ERIC Educational Resources Information Center

    Gamble, Harriet

    1998-01-01

    Transcribes an interview with Jafar Mogadam, an Iranian artist who paints Persian tiles. Traces Mogadam's development as an artist and describes how he creates his tile compositions. Provides a brief history of Persian tiles. (DSK)

  3. Low-Density, Aerogel-Filled Thermal-Insulation Tiles

    NASA Technical Reports Server (NTRS)

    Santos, Maryann; Heng, Vann; Barney, Andrea; Oka, Kris; Droege, Michael

    2005-01-01

    Aerogel fillings have been investigated in a continuing effort to develop low-density thermal-insulation tiles that, relative to prior such tiles, have greater dimensional stability (especially less shrinkage), equal or lower thermal conductivity, and greater strength and durability. In preparation for laboratory tests of dimensional and thermal stability, prototypes of aerogel-filled versions of recently developed low-density tiles have been fabricated by impregnating such tiles to various depths with aerogel formations ranging in density from 1.5 to 5.6 lb/ft3 (about 53 to 200 kg/cu m). Results available at the time of reporting the information for this article showed that the thermal-insulation properties of the partially or fully aerogel- impregnated tiles were equivalent or superior to those of the corresponding non-impregnated tiles and that the partially impregnated tiles exhibited minimal (<1.5 percent) shrinkage after multiple exposures at a temperature of 2,300 F (1,260 C). Latest developments have shown that tiles containing aerogels at the higher end of the density range are stable after multiple exposures at the said temperature.

  4. 44. East tile gauge on south pier. Each square tile ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    44. East tile gauge on south pier. Each square tile is 4' in size. Top left section of 4' square eagle section - Duluth Ship Canal, South Pier, North end of Minnesota Point & Canal Park, Duluth, St. Louis County, MN

  5. 47. East tile gauge on south pier. Each square tile ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    47. East tile gauge on south pier. Each square tile is 4' in size. Middle right section of 4' square eagle section - Duluth Ship Canal, South Pier, North end of Minnesota Point & Canal Park, Duluth, St. Louis County, MN

  6. 46. East tile gauge on south pier. Each square tile ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    46. East tile gauge on south pier. Each square tile is 4' in size. Lower right section of 4' square eagle section - Duluth Ship Canal, South Pier, North end of Minnesota Point & Canal Park, Duluth, St. Louis County, MN

  7. 43. East tile gauge on south pier. Each square tile ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    43. East tile gauge on south pier. Each square tile is 4' in size. Eagle itself in 4' square eagle section - Duluth Ship Canal, South Pier, North end of Minnesota Point & Canal Park, Duluth, St. Louis County, MN

  8. 45. East tile gauge on south pier. Each square tile ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    45. East tile gauge on south pier. Each square tile is 4' in size. Lower left section of 4' square eagel section - Duluth Ship Canal, South Pier, North end of Minnesota Point & Canal Park, Duluth, St. Louis County, MN

  9. 51. East tile gauge on south pier. Each square tile ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    51. East tile gauge on south pier. Each square tile is 4' in size. Lower end of cross second from bottom - Duluth Ship Canal, South Pier, North end of Minnesota Point & Canal Park, Duluth, St. Louis County, MN

  10. Geopolymers as potential repair material in tiles conservation

    NASA Astrophysics Data System (ADS)

    Geraldes, Catarina F. M.; Lima, Augusta M.; Delgado-Rodrigues, José; Mimoso, João Manuel; Pereira, Sílvia R. M.

    2016-03-01

    The restoration materials currently used to fill gaps in historical architectural tiles (e.g. lime or organic resin pastes) usually show serious drawbacks in terms of compatibility, effectiveness or durability. The existing solutions do not fully protect Portuguese faïence tiles ( azulejos) in outdoor conditions and frequently result in further deterioration. Geopolymers can be a potential solution for tile lacunae infill, given the chemical-mineralogical similitude to the ceramic body, and also the durability and versatile range of physical properties that can be obtained through the manipulation of their formulation and curing conditions. This work presents and discusses the viability of the use of geopolymeric pastes to fill lacunae in tiles or to act as "cold" cast ceramic tile surrogates reproducing missing tile fragments. The formulation of geopolymers, namely the type of activators, the alumino-silicate source, the quantity of water required for adequate workability and curing conditions, was studied. The need for post-curing desalination was also considered envisaging their application in the restoration of outdoor historical architectural tiles frequently exposed to adverse environmental conditions. The possible advantages and disadvantages of the use of geopolymers in the conservation of tiles are also discussed. The results obtained reveal that geopolymers pastes are a promising material for the restoration of tiles, when compared to other solutions currently in use.

  11. Interference Lattice-based Loop Nest Tilings for Stencil Computations

    NASA Technical Reports Server (NTRS)

    VanderWijngaart, Rob F.; Frumkin, Michael

    2000-01-01

    A common method for improving performance of stencil operations on structured multi-dimensional discretization grids is loop tiling. Tile shapes and sizes are usually determined heuristically, based on the size of the primary data cache. We provide a lower bound on the numbers of cache misses that must be incurred by any tiling, and a close achievable bound using a particular tiling based on the grid interference lattice. The latter tiling is used to derive highly efficient loop orderings. The total number of cache misses of a code is the sum of (necessary) cold misses and misses caused by elements being dropped from the cache between successive loads (replacement misses). Maximizing temporal locality is equivalent to minimizing replacement misses. Temporal locality of loop nests implementing stencil operations is optimized by tilings that avoid data conflicts. We divide the loop nest iteration space into conflict-free tiles, derived from the cache miss equation. The tiling involves the definition of the grid interference lattice an equivalence class of grid points whose images in main memory map to the same location in the cache-and the construction of a special basis for the lattice. Conflicts only occur on the boundaries of the tiles, unless the tiles are too thin. We show that the surface area of the tiles is bounded for grids of any dimensionality, and for caches of any associativity, provided the eccentricity of the fundamental parallelepiped (the tile spanned by the basis) of the lattice is bounded. Eccentricity is determined by two factors, aspect ratio and skewness. The aspect ratio of the parallelepiped can be bounded by appropriate array padding. The skewness can be bounded by the choice of a proper basis. Combining these two strategies ensures that pathologically thin tiles are avoided. They do not, however, minimize replacement misses per se. The reason is that tile visitation order influences the number of data conflicts on the tile boundaries. If two adjacent tiles are visited successively, there will be no replacement misses on the shared boundary. The iteration space may be covered with pencils larger than the size of the cache while avoiding data conflicts if the pencils are traversed by a scanning-face method. Replacement misses are incurred only on the boundaries of the pencils, and the number of misses is minimized by maximizing the volume of the scanning face, not the volume of the tile. We present an algorithm for constructing the most efficient scanning face for a given grid and stencil operator. In two dimensions it is based on a continued fraction algorithm. In three dimensions it follows Voronoi's successive minima algorithm. We show experimental results of using the scanning face, and compare with canonical loop orderings.

  12. Helioviewer.org: Browsing Very Large Image Archives Online Using JPEG 2000

    NASA Astrophysics Data System (ADS)

    Hughitt, V. K.; Ireland, J.; Mueller, D.; Dimitoglou, G.; Garcia Ortiz, J.; Schmidt, L.; Wamsler, B.; Beck, J.; Alexanderian, A.; Fleck, B.

    2009-12-01

    As the amount of solar data available to scientists continues to increase at faster and faster rates, it is important that there exist simple tools for navigating this data quickly with a minimal amount of effort. By combining heterogeneous solar physics datatypes such as full-disk images and coronagraphs, along with feature and event information, Helioviewer offers a simple and intuitive way to browse multiple datasets simultaneously. Images are stored in a repository using the JPEG 2000 format and tiled dynamically upon a client's request. By tiling images and serving only the portions of the image requested, it is possible for the client to work with very large images without having to fetch all of the data at once. In addition to a focus on intercommunication with other virtual observatories and browsers (VSO, HEK, etc), Helioviewer will offer a number of externally-available application programming interfaces (APIs) to enable easy third party use, adoption and extension. Recent efforts have resulted in increased performance, dynamic movie generation, and improved support for mobile web browsers. Future functionality will include: support for additional data-sources including RHESSI, SDO, STEREO, and TRACE, a navigable timeline of recorded solar events, social annotation, and basic client-side image processing.

  13. Density-dependent effects of omnivorous stream crayfish on benthic trophic dynamics

    USGS Publications Warehouse

    Ludlam, J.P.; Banks, B. T.; Magoulick, Daniel D.

    2015-01-01

    Crayfish are abundant and important consumers in aquatic food webs and crayfish invasions have demonstrated strong effects of crayfish on multiple trophic levels. Density may be an important factor determining the role of omnivorous crayfish in benthic communities, especially if density alters the strength of trophic interactions. The effect of crayfish density on a simple benthic food web using ceramic tiles was examined in three treatments (crayfish exclusion cage, cage control (open to crayfish), and exposed ceramic tiles) in mesocosms stocked with 6, 12, or 18 crayfish·m-2. We hypothesized that at low densities crayfish consumption of herbivorous chironomids would increase algal abundance, but at high densities crayfish would reduce both periphyton and invertebrates. In the experiment, periphyton and chironomid abundance increased with declining crayfish biomass on day 30 but not day 15. The magnitude of crayfish effects on day 15 periphyton chlorophyll a abundance increased with crayfish biomass, but crayfish effects on day 30 periphyton chlorophyll a or chironomid biomass did not increase with crayfish biomass. In this experiment there was little evidence for a trophic cascade at low crayfish densities and strong omnivory by crayfish dominated trophic dynamics.

  14. Research on Reasons for Repeated Falling of Tiles in Internal Walls of Construction

    NASA Astrophysics Data System (ADS)

    Xu, LiBin; Chen, Shangwei; He, Xinzhou; Zhu, Guoliang

    2018-03-01

    In view of the quality problem of repeated falling of facing tiles in some construction, the essay had a comparative trial in laboratory on cement mortar which is often used to paste tiles, special tile mortar and dry-hang glue, and measured durability of tile adhesive mortar through freezing and thawing tests. The test results indicated that ordinary cement mortar cannot meet standards due to reasons like big shrinkage and low adhesive. In addition, the ten times of freezing and thawing tests indicated that ordinary cement mortar would directly shell and do not have an adhesive force, and moreover, adhesive force of special tile mortar would reduce. Thus, for tiles of large size which are used for walls, dry-hang techniques are recommended to be used.

  15. Improve load balancing and coding efficiency of tiles in high efficiency video coding by adaptive tile boundary

    NASA Astrophysics Data System (ADS)

    Chan, Chia-Hsin; Tu, Chun-Chuan; Tsai, Wen-Jiin

    2017-01-01

    High efficiency video coding (HEVC) not only improves the coding efficiency drastically compared to the well-known H.264/AVC but also introduces coding tools for parallel processing, one of which is tiles. Tile partitioning is allowed to be arbitrary in HEVC, but how to decide tile boundaries remains an open issue. An adaptive tile boundary (ATB) method is proposed to select a better tile partitioning to improve load balancing (ATB-LoadB) and coding efficiency (ATB-Gain) with a unified scheme. Experimental results show that, compared to ordinary uniform-space partitioning, the proposed ATB can save up to 17.65% of encoding times in parallel encoding scenarios and can reduce up to 0.8% of total bit rates for coding efficiency.

  16. Retrosynthetic Analysis-Guided Breaking Tile Symmetry for the Assembly of Complex DNA Nanostructures.

    PubMed

    Wang, Pengfei; Wu, Siyu; Tian, Cheng; Yu, Guimei; Jiang, Wen; Wang, Guansong; Mao, Chengde

    2016-10-11

    Current tile-based DNA self-assembly produces simple repetitive or highly symmetric structures. In the case of 2D lattices, the unit cell often contains only one basic tile because the tiles often are symmetric (in terms of either the backbone or the sequence). In this work, we have applied retrosynthetic analysis to determine the minimal asymmetric units for complex DNA nanostructures. Such analysis guides us to break the intrinsic structural symmetries of the tiles to achieve high structural complexities. This strategy has led to the construction of several DNA nanostructures that are not accessible from conventional symmetric tile designs. Along with previous studies, herein we have established a set of four fundamental rules regarding tile-based assembly. Such rules could serve as guidelines for the design of DNA nanostructures.

  17. Recruitment and Succession in a Tropical Benthic Community in Response to In-Situ Ocean Acidification.

    PubMed

    Crook, Elizabeth Derse; Kroeker, Kristy J; Potts, Donald C; Rebolledo-Vieyra, Mario; Hernandez-Terrones, Laura M; Paytan, Adina

    2016-01-01

    Ocean acidification is a pervasive threat to coral reef ecosystems, and our understanding of the ecological processes driving patterns in tropical benthic community development in conditions of acidification is limited. We deployed limestone recruitment tiles in low aragonite saturation (Ωarag) waters during an in-situ field experiment at Puerto Morelos, Mexico, and compared them to tiles placed in control zones over a 14-month investigation. The early stages of succession showed relatively little difference in coverage of calcifying organisms between the low Ωarag and control zones. However, after 14 months of development, tiles from the low Ωarag zones had up to 70% less cover of calcifying organisms coincident with 42% more fleshy algae than the controls. The percent cover of biofilm and turf algae was also significantly greater in the low Ωarag zones, while the number of key grazing taxa remained constant. We hypothesize that fleshy algae have a competitive edge over the primary calcified space holders, coralline algae, and that acidification leads to altered competitive dynamics between various taxa. We suggest that as acidification impacts reefs in the future, there will be a shift in community assemblages away from upright and crustose coralline algae toward more fleshy algae and turf, established in the early stages of succession.

  18. Recruitment and Succession in a Tropical Benthic Community in Response to In-Situ Ocean Acidification

    PubMed Central

    Crook, Elizabeth Derse; Kroeker, Kristy J.; Potts, Donald C.; Rebolledo-Vieyra, Mario; Hernandez-Terrones, Laura M.; Paytan, Adina

    2016-01-01

    Ocean acidification is a pervasive threat to coral reef ecosystems, and our understanding of the ecological processes driving patterns in tropical benthic community development in conditions of acidification is limited. We deployed limestone recruitment tiles in low aragonite saturation (Ωarag) waters during an in-situ field experiment at Puerto Morelos, Mexico, and compared them to tiles placed in control zones over a 14-month investigation. The early stages of succession showed relatively little difference in coverage of calcifying organisms between the low Ωarag and control zones. However, after 14 months of development, tiles from the low Ωarag zones had up to 70% less cover of calcifying organisms coincident with 42% more fleshy algae than the controls. The percent cover of biofilm and turf algae was also significantly greater in the low Ωarag zones, while the number of key grazing taxa remained constant. We hypothesize that fleshy algae have a competitive edge over the primary calcified space holders, coralline algae, and that acidification leads to altered competitive dynamics between various taxa. We suggest that as acidification impacts reefs in the future, there will be a shift in community assemblages away from upright and crustose coralline algae toward more fleshy algae and turf, established in the early stages of succession. PMID:26784986

  19. Geospatial resources for the geologic community: The USGS National Map

    USGS Publications Warehouse

    Witt, Emitt C.

    2015-01-01

    Geospatial data are a key component of investigating, interpreting, and communicating the geological sciences. Locating geospatial data can be time-consuming, which detracts from time spent on a study because these data are not obviously placed in central locations or are served from many disparate databases. The National Map of the US Geological Survey is a publicly available resource for accessing the geospatial base map data needs of the geological community from a central location. The National Map data are available through a viewer and download platform providing access to eight primary data themes, plus the US Topo and scanned historical topographic maps. The eight themes are elevation, orthoimagery, hydrography, geographic names, boundaries, transportation, structures, and land cover, and they are being offered for download as predefined tiles in formats supported by leading geographic information system software. Data tiles are periodically refreshed to capture the most current content and are an efficient method for disseminating and receiving geospatial information. Elevation data, for example, are offered as a download from the National Map as 1° × 1° tiles for the 10- and 30- m products and as 15′ × 15′ tiles for the higher-resolution 3-m product. Vector data sets with smaller file sizes are offered at several tile sizes and formats. Partial tiles are not a download option—any prestaged data that intersect the requesting bounding box will be, in their entirety, part of the download order. While there are many options for accessing geospatial data via the Web, the National Map represents authoritative sources of data that are documented and can be referenced for citation and inclusion in scientific publications. Therefore, National Map products and services should be part of a geologist’s first stop for geospatial information and data.

  20. The role of C:N:P stoichiometry in affecting denitrification in sediments from agricultural surface and tile-water wetlands.

    PubMed

    Grebliunas, Brian D; Perry, William L

    2016-01-01

    Nutrient stoichiometry within a wetland is affected by the surrounding land use, and may play a significant role in the removal of nitrate (NO3-N). Tile-drained, agricultural watersheds experience high seasonal inputs of NO3-N, but low phosphorus (PO4-P) and dissolved organic carbon (DOC) loads relative to surface water dominated systems. This difference may present stoichiometric conditions that limit denitrification within receiving waterways. We investigated how C:N:P ratios affected denitrification rates of sediments from tile-drained mitigation wetlands incubated for: 0, 5, 10, and 20 days. We then tested whether denitrification rates of sediments from surface-water and tile-drained wetlands responded differently to C:N ratios of 2:1 versus 4:1. Ratios of C:N:P (P < 0.05) and incubation length (P < 0.05) had a significant effect on denitrification in tile-drained wetland sediments. Carbon limitation of denitrification became evident at elevated NO3-N concentrations (20 mg L(-1)). Denitrification measured from tile water and surface water wetland sediments increased significantly (P < 0.05) at the 2:1 and 4:1 C:N treatments. The results from both experiments suggest wetland sediments provide a limiting pool of labile DOC to maintain prolonged NO3-N removal. Also, DOC limitation became more evident at elevated NO3-N concentrations (20 mg L(-1)). Irrespective of NO3-N concentrations, P did not limit denitrification rates. In addition to wetting period, residence time, and maintenance of anaerobic conditions, the availability of labile DOC is playing an important limiting role in sediment denitrification within mitigation wetlands.

  1. Dual permeability modeling of tile drain management influences on hydrologic and nutrient transport characteristics in macroporous soil

    NASA Astrophysics Data System (ADS)

    Frey, Steven K.; Hwang, Hyoun-Tae; Park, Young-Jin; Hussain, Syed I.; Gottschall, Natalie; Edwards, Mark; Lapen, David R.

    2016-04-01

    Tile drainage management is considered a beneficial management practice (BMP) for reducing nutrient loads in surface water. In this study, 2-dimensional dual permeability models were developed to simulate flow and transport following liquid swine manure and rhodamine WT (strongly sorbing) tracer application on macroporous clay loam soils under controlled (CD) and free drainage (FD) tile management. Dominant flow and transport characteristics were successfully replicated, including higher and more continuous tile discharge and lower peak rhodamine WT concentrations in FD tile effluent; in relation to CD, where discharge was intermittent, peak rhodamine concentrations higher, and mass exchange from macropores into the soil matrix greater. Explicit representation of preferential flow was essential, as macropores transmitted >98% of surface infiltration, tile flow, and tile solute loads for both FD and CD. Incorporating an active 3rd type lower boundary condition that facilitated groundwater interaction was imperative for simulating CD, as the higher (relative to FD) water table enhanced water and soluble nutrient movement from the soil profile into deeper groundwater. Scenario analysis revealed that in conditions where slight upwards hydraulic gradients exist beneath tiles, groundwater upwelling can influence the concentration of surface derived solutes in tile effluent under FD conditions; whereas the higher and flatter CD water table can restrict groundwater upwelling. Results show that while CD can reduce tile discharge, it can also lead to an increase in surface-application derived nutrient concentrations in tile effluent and hence surface water receptors, and it can promote NO3 loading into groundwater. This study demonstrates dual permeability modeling as a tool for increasing the conceptual understanding of tile drainage BMPs.

  2. KSC-2011-1402

    NASA Image and Video Library

    2011-02-08

    CAPE CANAVERAL, Fla. -- In Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida, a thermal protection system technician is replacing a heat shield tile under space shuttle Atlantis. The tiles are part of the Orbiter Thermal Protection System, thermal shields to protect against temperatures as high as 3,000 degrees Fahrenheit, which are produced during descent for landing. Atlantis is being prepared for the STS-135 mission, which will deliver the Raffaello multi-purpose logistics module packed with supplies, logistics and spare parts to the International Space Station. STS-135 is targeted to launch June 28, and will be the last spaceflight for the Space Shuttle Program. Photo credit: NASA/Jack Pfaller

  3. KSC-2011-1477

    NASA Image and Video Library

    2011-02-17

    CAPE CANAVERAL, Fla. -- In Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida, a thermal protection system technician places a heat shield tile into position under space shuttle Atlantis. The tiles are part of the Orbiter Thermal Protection System that protects the shuttle against temperatures as high as 3,000 degrees Fahrenheit, which are produced during descent for landing. Atlantis is being prepared for the STS-135 mission, which will carry the Raffaello multi-purpose logistics module packed with supplies, logistics and spare parts to the International Space Station. STS-135 is targeted to launch June 28, and will be the last flight for the Space Shuttle Program. Photo credit: NASA/Jack Pfaller

  4. Paster (brick and tile) 773.884; Tile Placer (brick and tile) 573.687; Tile Sorter (brick and tile) 573.887 -- Technical Report on Standardization of the General Aptitude Test Battery.

    ERIC Educational Resources Information Center

    Manpower Administration (DOL), Washington, DC. U.S. Training and Employment Service.

    The United States Training and Employment Service General Aptitude Test Battery (GATB), first published in 1947, has been included in a continuing program of research to validate the tests against success in many different occupations. The GATB consists of 12 tests which measure nine aptitudes: General Learning Ability; Verbal Aptitude; Numerical…

  5. Space Shuttle Communications Coverage Analysis for Thermal Tile Inspection

    NASA Technical Reports Server (NTRS)

    Kroll, Quin D.; Hwu, Shian U.; Upanavage, Matthew; Boster, John P.; Chavez, Mark A.

    2009-01-01

    The space shuttle ultra-high frequency Space-to-Space Communication System has to provide adequate communication coverage for astronauts who are performing thermal tile inspection and repair on the underside of the space shuttle orbiter (SSO). Careful planning and quantitative assessment are necessary to ensure successful system operations and mission safety in this work environment. This study assesses communication systems performance for astronauts who are working in the underside, non-line-of-sight shadow region on the space shuttle. All of the space shuttle and International Space Station (ISS) transmitting antennas are blocked by the SSO structure. To ensure communication coverage at planned inspection worksites, the signal strength and link margin between the SSO/ISS antennas and the extravehicular activity astronauts, whose line-of-sight is blocked by vehicle structure, was analyzed. Investigations were performed using rigorous computational electromagnetic modeling techniques. Signal strength was obtained by computing the reflected and diffracted fields along the signal propagation paths between transmitting and receiving antennas. Radio frequency (RF) coverage was determined for thermal tile inspection and repair missions using the results of this computation. Analysis results from this paper are important in formulating the limits on reliable communication range and RF coverage at planned underside inspection and repair worksites.

  6. Three-dimensional digital breast histopathology imaging

    NASA Astrophysics Data System (ADS)

    Clarke, G. M.; Peressotti, C.; Mawdsley, G. E.; Eidt, S.; Ge, M.; Morgan, T.; Zubovits, J. T.; Yaffe, M. J.

    2005-04-01

    We have developed a digital histology imaging system that has the potential to improve the accuracy of surgical margin assessment in the treatment of breast cancer by providing finer sampling and 3D visualization. The system is capable of producing a 3D representation of histopathology from an entire lumpectomy specimen. We acquire digital photomicrographs of a stack of large (120 x 170 mm) histology slides cut serially through the entire specimen. The images are then registered and displayed in 2D and 3D. This approach dramatically improves sampling and can improve visualization of tissue structures compared to current, small-format histology. The system consists of a brightfield microscope, adapted with a freeze-frame digital video camera and a large, motorized translation stage. The image of each slide is acquired as a mosaic of adjacent tiles, each tile representing one field-of-view of the microscope, and the mosaic is assembled into a seamless composite image. The assembly is done by a program developed to build image sets at six different levels within a multiresolution pyramid. A database-linked viewing program has been created to efficiently register and display the animated stack of images, which occupies about 80 GB of disk space per lumpectomy at full resolution, on a high-resolution (3840 x 2400 pixels) colour monitor. The scanning or tiling approach to digitization is inherently susceptible to two artefacts which disrupt the composite image, and which impose more stringent requirements on system performance. Although non-uniform illumination across any one isolated tile may not be discernible, the eye readily detects this non-uniformity when the entire assembly of tiles is viewed. The pattern is caused by deficiencies in optical alignment, spectrum of the light source, or camera corrections. The imaging task requires that features as small as 3.2 &mum in extent be seamlessly preserved. However, inadequate accuracy in positioning of the translation stage produces visible discontinuities between adjacent features. Both of these effects can distract the viewer from the perception of diagnostically important features. Here we describe the system design and discuss methods for the correction of these artefacts. In addition, we outline our approach to rendering the processing and display of these large images computationally feasible.

  7. 40 CFR 427.70 - Applicability; description of the asbestos floor tile subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... asbestos floor tile subcategory. 427.70 Section 427.70 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos Floor Tile Subcategory § 427.70 Applicability; description of the asbestos floor tile subcategory...

  8. 40 CFR 427.70 - Applicability; description of the asbestos floor tile subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... asbestos floor tile subcategory. 427.70 Section 427.70 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos Floor Tile Subcategory § 427.70 Applicability; description of the asbestos floor tile...

  9. 40 CFR 427.70 - Applicability; description of the asbestos floor tile subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... asbestos floor tile subcategory. 427.70 Section 427.70 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos Floor Tile Subcategory § 427.70 Applicability; description of the asbestos floor tile subcategory...

  10. 40 CFR 427.70 - Applicability; description of the asbestos floor tile subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... asbestos floor tile subcategory. 427.70 Section 427.70 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos Floor Tile Subcategory § 427.70 Applicability; description of the asbestos floor tile...

  11. 40 CFR 427.70 - Applicability; description of the asbestos floor tile subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... asbestos floor tile subcategory. 427.70 Section 427.70 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos Floor Tile Subcategory § 427.70 Applicability; description of the asbestos floor tile...

  12. Spectral response data for development of cool coloured tile coverings

    NASA Astrophysics Data System (ADS)

    Libbra, Antonio; Tarozzi, Luca; Muscio, Alberto; Corticelli, Mauro A.

    2011-03-01

    Most ancient or traditional buildings in Italy show steep-slope roofs covered by red clay tiles. As the rooms immediately below the roof are often inhabited in historical or densely urbanized centres, the combination of low solar reflectance of tile coverings and low thermal inertia of either wooden roof structures or sub-tile insulation panels makes summer overheating a major problem. The problem can be mitigated by using tiles coated with cool colours, that is colours with the same spectral response of clay tiles in the visible, but highly reflecting in the near infrared range, which includes more than half of solar radiation. Cool colours can yield the same visible aspect of common building surfaces, but higher solar reflectance. Studies aimed at developing cool colour tile coverings for traditional Italian buildings have been started. A few coating solutions with the typical red terracotta colour have been produced and tested in the laboratory, using easily available materials. The spectral response and the solar reflectance have been measured and compared with that of standard tiles.

  13. Archimedean Voronoi spiral tilings

    NASA Astrophysics Data System (ADS)

    Yamagishi, Yoshikazu; Sushida, Takamichi

    2018-01-01

    We study the transition of the number of spirals (called parastichy in the theory of phyllotaxis) within a Voronoi tiling for Archimedean spiral lattices. The transition of local parastichy numbers within a tiling is regarded as a transition at the base site point in a continuous family of tilings. This gives a natural description of the quasiperiodic structure of the grain boundaries. It is proved that the number of tiles in the grain boundaries are denominators of rational approximations of the argument (called the divergence angle) of the generator. The local parastichy numbers are non-decreasing functions of the plastochron parameter. The bifurcation diagram of local parastichy numbers has a Farey tree structure. We also prove Richards’ formula of spiral phyllotaxis in the case of Archimedean Voronoi spiral tilings, and show that, if the divergence angle is a quadratic irrational number, then the shapes of tiles in the grain boundaries are close to rectangles. If the divergence angle is linearly equivalent to the golden section, then the shape of tiles in the grain boundaries is close to square.

  14. KSC-2012-1575

    NASA Image and Video Library

    2012-03-01

    CAPE CANAVERAL, Fla. -- The heat shield tiles that will be installed to the backshell of the Orion Multi-Purpose Crew Vehicle's Exploration Flight Test EFT-1 capsule are in a Keith thermal automation oven in the Thermal Protection System Facility at NASA's Kennedy Space Center in Florida. Inside the oven, the tiles will be baked at 2,200 degrees F to cure their ceramic coating. EFT-1 will be used during Orion's first test flight in space. For more information, visit www.nasa.gov/orion. Photo credit: Frankie Martin

  15. KSC-2012-1576

    NASA Image and Video Library

    2012-03-01

    CAPE CANAVERAL, Fla. -- The heat shield tiles that will be installed to the backshell of the Orion Multi-Purpose Crew Vehicle's Exploration Flight Test EFT-1 capsule are in a Keith thermal automation oven in the Thermal Protection System Facility at NASA's Kennedy Space Center in Florida. Inside the oven, the tiles will be baked at 2,200 degrees F to cure their ceramic coating. EFT-1 will be used during Orion's first test flight in space. For more information, visit www.nasa.gov/orion. Photo credit: Frankie Martin

  16. International Space Station US. GN&C Momentum Manager Controller Design for Shuttle Thermal Protection System Repair

    NASA Technical Reports Server (NTRS)

    Sims, Christopher R.

    2005-01-01

    This paper describes the design of the ISS Momentum Manager controllers for the Orbiter Repair Maneuver (ORM) and Orbiter Tile Repair operations. Momentum Manager Controllers provide non-propulsive attitude control via CMGs. Non-propulsive control is required at the beginning and the middle of the ORM and at the tile repair position. This paper first reviews the design issues and requirements, then presents the design methodology, and concludes with analysis results that verify the design.

  17. KSC-2012-1594

    NASA Image and Video Library

    2012-03-01

    CAPE CANAVERAL, Fla. -- Jimmy Savastio, a United Space Alliance machinist at NASA's Kennedy Space Center in Florida, monitors the properties of a heat shield tile that will be installed to the backshell of the Orion Multi-Purpose Crew Vehicle's Exploration Flight Test EFT-1 capsule. The work to manufacture and inspect the tiles is taking place in Kennedy's Thermal Protection System Facility. EFT-1 will be used during Orion's first test flight in space. For more information, visit www.nasa.gov/orion. Photo credit: Frankie Martin

  18. KSC-2012-1588

    NASA Image and Video Library

    2012-03-01

    CAPE CANAVERAL, Fla. -- Tim Wright, a United Space Alliance engineering manager at NASA's Kennedy Space Center in Florida, explains the properties of the heat shield tiles that will be installed to the backshell of the Orion Multi-Purpose Crew Vehicle's Exploration Flight Test EFT-1 capsule. The work to manufacture and inspect the tiles is taking place in Kennedy's Thermal Protection System Facility. EFT-1 will be used during Orion's first test flight in space. For more information, visit www.nasa.gov/orion. Photo credit: Frankie Martin

  19. Effects of Climate Change in the Water Balance of a Modified River Watershed System in Central Illinois

    NASA Astrophysics Data System (ADS)

    Honings, J.; Seyoum, W. M.

    2017-12-01

    Understanding the response of water cycle dynamics to climate change and human activity is essential for best management of water resources. This study used the USDA Soil-Water Assessment Tool (SWAT) to measure and predict major water balance variables including stream discharge, potential aquifer recharge, and surface storage in a small-scale watershed ( 2,930 km²) in Central Illinois. The Mackinaw River drains the study watershed, which is predominantly tile-drained agricultural land. Two reservoirs, Evergreen Lake and Lake Bloomington, and the Mahomet Aquifer in the watershed are used for public water supply. Tiles modify watershed hydrology by efficiently draining water from saturated soil to streams, which increases total streamflow and reduces direct aquifer recharge from precipitation. To assess how the watershed is affected by future climate change, this study used high-resolution climate projection data ( 12 km) in a calibrated and validated SWAT hydrologic model. Using General Circulation Models, four (4) representative concentration pathways (RCPs) developed by the IPCC Coupled Model Intercomparison Project Fifth Assessment Report (CMIP5) were used for prediction of precipitation, mean, minimum, and maximum temperature for the watershed. Temperature predictions for 2050 were warmer for RCPs 2.6 and 8.0 (+0.69°C and +1.8°C), coinciding with increased precipitation rates (+2.5% and +4.3%). End of century projections indicate warmer mean temperatures (+0.66°C and +4.9°C) for RCPs 2.6 and 8.0. By 2099, precipitation predictions are wetter for RCP 8.0 (+10%), but drier for RCP 2.6 (-2%) from the baseline. Preliminary model calibration (R2 value = 0.7) results showed an annual average watershed yield of 32.8 m³/s at the outlet with average potential recharge of 18% of total precipitation. Tile flow comprises 10 to 30% of total flow in the watershed simulations. Predicted hydrologic variables for the extreme scenarios at mid- and end of century indicate +4.1% total flow and +4.8% recharge for RCP 2.6, compared to +4.5% total flow and +11% recharge for RCP 8.0. Effects of tile drainage and other management practices in the watershed will be examined under climate change scenarios. Model results will be used to aid future decisions involving water resource consumption and agricultural management.

  20. Upgrade of the ATLAS Hadronic Tile Calorimeter for the High Luminosity LHC

    NASA Astrophysics Data System (ADS)

    Tortajada, Ignacio Asensi

    2018-01-01

    The Large Hadron Collider (LHC) has envisaged a series of upgrades towards a High Luminosity LHC (HL-LHC) delivering five times the LHC nominal instantaneous luminosity. The ATLAS Phase II upgrade, in 2024, will accommodate the upgrade of the detector and data acquisition system for the HL-LHC. The Tile Calorimeter (TileCal) will undergo a major replacement of its on- and off-detector electronics. In the new architecture, all signals will be digitized and then transferred directly to the off-detector electronics, where the signals will be reconstructed, stored, and sent to the first level of trigger at the rate of 40 MHz. This will provide better precision of the calorimeter signals used by the trigger system and will allow the development of more complex trigger algorithms. Changes to the electronics will also contribute to the reliability and redundancy of the system. Three different front-end options are presently being investigated for the upgrade, two of them based on ASICs, and a final solution will be chosen after extensive laboratory and test beam studies that are in progress. A hybrid demonstrator module is being developed using the new electronics while conserving compatibility with the current system. The status of the developments will be presented, including results from the several tests with particle beams.

  1. Computerized Machine for Cutting Space Shuttle Thermal Tiles

    NASA Technical Reports Server (NTRS)

    Ramirez, Luis E.; Reuter, Lisa A.

    2009-01-01

    A report presents the concept of a machine aboard the space shuttle that would cut oversized thermal-tile blanks to precise sizes and shapes needed to replace tiles that were damaged or lost during ascent to orbit. The machine would include a computer-controlled jigsaw enclosed in a clear acrylic shell that would prevent escape of cutting debris. A vacuum motor would collect the debris into a reservoir and would hold a tile blank securely in place. A database stored in the computer would contain the unique shape and dimensions of every tile. Once a broken or missing tile was identified, its identification number would be entered into the computer, wherein the cutting pattern associated with that number would be retrieved from the database. A tile blank would be locked into a crib in the machine, the shell would be closed (proximity sensors would prevent activation of the machine while the shell was open), and a "cut" command would be sent from the computer. A blade would be moved around the crib like a plotter, cutting the tile to the required size and shape. Once the tile was cut, an astronaut would take a space walk for installation.

  2. Automation of Shuttle Tile Inspection - Engineering methodology for Space Station

    NASA Technical Reports Server (NTRS)

    Wiskerchen, M. J.; Mollakarimi, C.

    1987-01-01

    The Space Systems Integration and Operations Research Applications (SIORA) Program was initiated in late 1986 as a cooperative applications research effort between Stanford University, NASA Kennedy Space Center, and Lockheed Space Operations Company. One of the major initial SIORA tasks was the application of automation and robotics technology to all aspects of the Shuttle tile processing and inspection system. This effort has adopted a systems engineering approach consisting of an integrated set of rapid prototyping testbeds in which a government/university/industry team of users, technologists, and engineers test and evaluate new concepts and technologies within the operational world of Shuttle. These integrated testbeds include speech recognition and synthesis, laser imaging inspection systems, distributed Ada programming environments, distributed relational database architectures, distributed computer network architectures, multimedia workbenches, and human factors considerations.

  3. 40 CFR 63.8535 - Am I subject to this subpart?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... manufacturing facility is a plant site that manufactures pressed floor tile, pressed wall tile, other pressed tile, or sanitaryware (e.g., sinks and toilets). Clay ceramics manufacturing facilities typically process clay, shale, and various additives; form the processed materials into tile or sanitaryware shapes...

  4. 40 CFR 63.8535 - Am I subject to this subpart?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... manufacturing facility is a plant site that manufactures pressed floor tile, pressed wall tile, other pressed tile, or sanitaryware (e.g., sinks and toilets). Clay ceramics manufacturing facilities typically process clay, shale, and various additives; form the processed materials into tile or sanitaryware shapes...

  5. 40 CFR 63.8535 - Am I subject to this subpart?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... manufacturing facility is a plant site that manufactures pressed floor tile, pressed wall tile, other pressed tile, or sanitaryware (e.g., sinks and toilets). Clay ceramics manufacturing facilities typically process clay, shale, and various additives; form the processed materials into tile or sanitaryware shapes...

  6. 40 CFR 63.8535 - Am I subject to this subpart?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... manufacturing facility is a plant site that manufactures pressed floor tile, pressed wall tile, other pressed tile, or sanitaryware (e.g., sinks and toilets). Clay ceramics manufacturing facilities typically process clay, shale, and various additives; form the processed materials into tile or sanitaryware shapes...

  7. 40 CFR 63.8535 - Am I subject to this subpart?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... manufacturing facility is a plant site that manufactures pressed floor tile, pressed wall tile, other pressed tile, or sanitaryware (e.g., sinks and toilets). Clay ceramics manufacturing facilities typically process clay, shale, and various additives; form the processed materials into tile or sanitaryware shapes...

  8. Optimizing searches for electromagnetic counterparts of gravitational wave triggers

    NASA Astrophysics Data System (ADS)

    Coughlin, Michael W.; Tao, Duo; Chan, Man Leong; Chatterjee, Deep; Christensen, Nelson; Ghosh, Shaon; Greco, Giuseppe; Hu, Yiming; Kapadia, Shasvath; Rana, Javed; Salafia, Om Sharan; Stubbs11, Christopher

    2018-04-01

    With the detection of a binary neutron star system and its corresponding electromagnetic counterparts, a new window of transient astronomy has opened. Due to the size of the sky localization regions, which can span hundreds to thousands of square degrees, there are significant benefits to optimizing tilings for these large sky areas. The rich science promised by gravitational-wave astronomy has led to the proposal for a variety of proposed tiling and time allocation schemes, and for the first time, we make a systematic comparison of some of these methods. We find that differences of a factor of 2 or more in efficiency are possible, depending on the algorithm employed. For this reason, with future surveys searching for electromagnetic counterparts, care should be taken when selecting tiling, time allocation, and scheduling algorithms to optimize counterpart detection.

  9. Optimizing searches for electromagnetic counterparts of gravitational wave triggers

    NASA Astrophysics Data System (ADS)

    Coughlin, Michael W.; Tao, Duo; Chan, Man Leong; Chatterjee, Deep; Christensen, Nelson; Ghosh, Shaon; Greco, Giuseppe; Hu, Yiming; Kapadia, Shasvath; Rana, Javed; Salafia, Om Sharan; Stubbs, Christopher W.

    2018-07-01

    With the detection of a binary neutron star system and its corresponding electromagnetic counterparts, a new window of transient astronomy has opened. Due to the size of the sky localization regions, which can span hundreds to thousands of square degrees, there are significant benefits to optimizing tilings for these large sky areas. The rich science promised by gravitational wave astronomy has led to the proposal for a variety of proposed tiling and time allocation schemes, and for the first time, we make a systematic comparison of some of these methods. We find that differences of a factor of 2 or more in efficiency are possible, depending on the algorithm employed. For this reason, with future surveys searching for electromagnetic counterparts, care should be taken when selecting tiling, time allocation, and scheduling algorithms to optimize counterpart detection.

  10. Strong parameterization and coordination encirclements of graph of Penrose tiling vertices

    NASA Astrophysics Data System (ADS)

    Shutov, A. V.; Maleev, A. V.

    2017-07-01

    The coordination encirclements in a graph of Penrose tiling vertices have been investigated based on the analysis of vertice parameters. A strong parameterization of these vertices is developed in the form of a tiling of a parameter set in the region corresponding to different first coordination encirclements of vertices. An algorithm for constructing tilings of a set of parameters determining different coordination encirclements in a graph of Penrose tiling vertices of order n is proposed.

  11. 3D visualization of unsteady 2D airplane wake vortices

    NASA Technical Reports Server (NTRS)

    Ma, Kwan-Liu; Zheng, Z. C.

    1994-01-01

    Air flowing around the wing tips of an airplane forms horizontal tornado-like vortices that can be dangerous to following aircraft. The dynamics of such vortices, including ground and atmospheric effects, can be predicted by numerical simulation, allowing the safety and capacity of airports to be improved. In this paper, we introduce three-dimensional techniques for visualizing time-dependent, two-dimensional wake vortex computations, and the hazard strength of such vortices near the ground. We describe a vortex core tracing algorithm and a local tiling method to visualize the vortex evolution. The tiling method converts time-dependent, two-dimensional vortex cores into three-dimensional vortex tubes. Finally, a novel approach calculates the induced rolling moment on the following airplane at each grid point within a region near the vortex tubes and thus allows three-dimensional visualization of the hazard strength of the vortices. We also suggest ways of combining multiple visualization methods to present more information simultaneously.

  12. Water and Nutrient Balances in a Large Tile-Drained Agricultural Catchment: A Distributed Modeling Study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, Hongyi; Sivapalan, Murugesu; Tian, Fuqiang

    This paper presents the development and implementation of a distributed model of coupled water nutrient processes, based on the representative elementary watershed (REW) approach, to the Upper Sangamon River Basin, a large, tile-drained agricultural basin located in central Illinois, mid-west of USA. Comparison of model predictions with the observed hydrological and biogeochemical data, as well as regional estimates from literature studies, shows that the model is capable of capturing the dynamics of water, sediment and nutrient cycles reasonably well. The model is then used as a tool to gain insights into the physical and chemical processes underlying the inter- andmore » intra-annual variability of water and nutrient balances. Model predictions show that about 80% of annual runoff is contributed by tile drainage, while the remainder comes from surface runoff (mainly saturation excess flow) and subsurface runoff. It is also found that, at the annual scale nitrogen storage in the soil is depleted during wet years, and is supplemented during dry years. This carryover of nitrogen storage from dry year to wet year is mainly caused by the lateral loading of nitrate. Phosphorus storage, on the other hand, is not affected much by wet/dry conditions simply because the leaching of it is very minor compared to the other mechanisms taking phosphorous out of the basin, such as crop harvest. The analysis then turned to the movement of nitrate with runoff. Model results suggested that nitrate loading from hillslope into the channel is preferentially carried by tile drainage. Once in the stream it is then subject to in-stream denitrification, the significant spatio-temporal variability of which can be related to the variation of the hydrologic and hydraulic conditions across the river network.« less

  13. GROWTH EVALUATION OF FUNGI (PENICILLIUM AND ASPERGILLUS SPP.) ON CEILING TILES

    EPA Science Inventory

    The paper gives results of an evaluation of the potential for fungal growth on four different ceiling tiles in static chambers. It was found that even new ceiling tiles supported fungal growth under favorable conditions. Used ceiling tiles appeared to be more susceptible to funga...

  14. Effect of tile effluent on nutrient concentration and retention efficiency in agricultural drainage ditches

    USDA-ARS?s Scientific Manuscript database

    Tile drainage is a common water management practice in many agricultural landscapes in the Midwestern United States. Drainage ditches regularly receive water from agricultural fields through these tile drains. This field-scale study was conducted to determine the impact of tile discharge on ambient ...

  15. 7 CFR 28.956 - Prescribed fees.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    .... sample 42.00 3.0Furnishing standard color tiles for calibrating cotton colormeters, per set of five tiles... outside continental United States 165.00 3.1Furnishing single color calibration tiles for use with specific instruments or as replacements in above sets, each tile: a. f.o.b. Memphis, Tennessee 22.00 b...

  16. Two Views of Islam: Ceramic Tile Design and Miniatures.

    ERIC Educational Resources Information Center

    Macaulay, Sara Grove

    2001-01-01

    Describes an art project focusing on Islamic art that consists of two parts: (1) ceramic tile design; and (2) Islamic miniatures. Provides background information on Islamic art and step-by-step instructions for designing the Islamic tile and miniature. Includes learning objectives and resources on Islamic tile miniatures. (CMK)

  17. 7 CFR 28.956 - Prescribed fees.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    .... sample 42.00 3.0Furnishing standard color tiles for calibrating cotton colormeters, per set of five tiles... outside continental United States 165.00 3.1Furnishing single color calibration tiles for use with specific instruments or as replacements in above sets, each tile: a. f.o.b. Memphis, Tennessee 22.00 b...

  18. Laser ultrasonics for bulk-density distribution measurement on green ceramic tiles

    NASA Astrophysics Data System (ADS)

    Revel, G. M.; Cavuto, A.; Pandarese, G.

    2016-10-01

    In this paper a Laser Ultrasonics (LUT) system is developed and applied to measure bulk density distribution of green ceramic tiles, which are porous materials with low heat conductivity. Bulk density of green ceramic bodies is a fundamental parameter to be kept under control in the industrial production of ceramic tiles. The LUT system proposed is based on a Nd:YAG pulsed laser for excitation and an air-coupled electro-capacitive transducer for detection. The paper reports experimental apparent bulk-density measurements on white ceramic bodies after a calibration procedures. The performances observed are better than those previously achieved by authors using air-coupled ultrasonic probes for both emission and detection, allowing to reduce average uncertainty down to about ±6 kg/m3 (±0.3%), thanks to the increase in excitation efficiency and lateral resolution, while maintaining potential flexibility for on-line application. The laser ultrasonic procedure proposed is available for both on-line and off-line application. In this last case it is possible to obtain bulk density maps with high spatial resolution by a 2D scan without interrupting the production process.

  19. Machine Learning Techniques for Persuasion Detection in Conversation

    DTIC Science & Technology

    2010-06-01

    files maintained the original post and tile ordering within each transcript. These files were each internally shuffled prior to creating test and...of the number of post or tiles. The other 90% was used for training data. Each post and each tile appeared in only one of the 10 test sets. Each post ...concatenating 5 test sets and pairing it with the 6th test set. This process was conducted for both posts and tiles. The shortest transcript (19 posts , 0 tiles

  20. Numerical Simulation of Ballistic Impact of Layered Aluminum Nitride Ceramic

    DTIC Science & Technology

    2015-09-01

    tile(s) Aluminum nitride (AlN) 163 a Polymer layers Polyurethane foam 18 b Backing metal Aluminum 6061-T6 (Al) 23 c Projectile Tungsten heavy alloy...larger (a factor of 3.8) than the most dense polyurethane foam of the available constitutive models. Default options for element failure were imposed in...AlN), a polycrystalline ceramic. The total thickness of the tile(s) is 38.1 mm in all cases. A thin polyurethane laminate separates neighboring tiles

  1. Rye cover crop and gamagrass strip effects on NO3 concentration and load in tile drainage.

    PubMed

    Kaspar, T C; Jaynes, D B; Parkin, T B; Moorman, T B

    2007-01-01

    A significant portion of the NO3 from agricultural fields that contaminates surface waters in the Midwest Corn Belt is transported to streams or rivers by subsurface drainage systems or "tiles." Previous research has shown that N fertilizer management alone is not sufficient for reducing NO3 concentrations in subsurface drainage to acceptable levels; therefore, additional approaches need to be devised. We compared two cropping system modifications for NO3 concentration and load in subsurface drainage water for a no-till corn (Zea mays L.)-soybean (Glycine max [L.] Merr.) management system. In one treatment, eastern gamagrass (Tripsacum dactyloides L.) was grown in permanent 3.05-m-wide strips above the tiles. For the second treatment, a rye (Secale cereale L.) winter cover crop was seeded over the entire plot area each year near harvest and chemically killed before planting the following spring. Twelve 30.5x42.7-m subsurface-drained field plots were established in 1999 with an automated system for measuring tile flow and collecting flow-weighted samples. Both treatments and a control were initiated in 2000 and replicated four times. Full establishment of both treatments did not occur until fall 2001 because of dry conditions. Treatment comparisons were conducted from 2002 through 2005. The rye cover crop treatment significantly reduced subsurface drainage water flow-weighted NO3 concentrations and NO3 loads in all 4 yr. The rye cover crop treatment did not significantly reduce cumulative annual drainage. Averaged over 4 yr, the rye cover crop reduced flow-weighted NO3 concentrations by 59% and loads by 61%. The gamagrass strips did not significantly reduce cumulative drainage, the average annual flow-weighted NO3 concentrations, or cumulative NO3 loads averaged over the 4 yr. Rye winter cover crops grown after corn and soybean have the potential to reduce the NO3 concentrations and loads delivered to surface waters by subsurface drainage systems.

  2. KSC-08pd1966

    NASA Image and Video Library

    2008-07-14

    CAPE CANAVERAL, Fla. – In the tile shop at NASA's Kennedy Space Center, a worker places a Boeing Replacement Insulation 18, or BRI-18, tile in the oven. The tile will be baked at 2,200 degrees Fahrenheit to cure the ceramic coating, part of the process to prepare the tiles for installation on space shuttles. BRI-18 is the strongest material used for thermal insulation on the orbiters and, when coated to produce toughened unipiece fibrous insulation, provides a tile with extremely high-impact resistance. It is replacing other tiles on areas of the vehicle where impact risk is high, such as the landing gear doors, the wing leading edge and the external tank doors. Photo credit: NASA/Jim Grossmann

  3. The First Static and Dynamic Analysis of 3-D Printed Sintered Ceramics for Body Armor Applications

    DTIC Science & Technology

    2016-09-01

    evaluate sintered alumina tiles produced by 3-D printing methodology. This report examines the static and quasi -static parameters (including density...Figures iv List of Tables iv Acknowledgments v 1. Introduction 1 2. Processing and Experimental Procedures 1 3. Results and Discussion 7 4...6 Fig. 8 Experimental setup for recording fracture .............................................7 Fig. 9 Rod projectile

  4. Directed nucleation assembly of DNA tile complexes for barcode-patterned lattices

    NASA Astrophysics Data System (ADS)

    Yan, Hao; Labean, Thomas H.; Feng, Liping; Reif, John H.

    2003-07-01

    The programmed self-assembly of patterned aperiodic molecular structures is a major challenge in nanotechnology and has numerous potential applications for nanofabrication of complex structures and useful devices. Here we report the construction of an aperiodic patterned DNA lattice (barcode lattice) by a self-assembly process of directed nucleation of DNA tiles around a scaffold DNA strand. The input DNA scaffold strand, constructed by ligation of shorter synthetic oligonucleotides, provides layers of the DNA lattice with barcode patterning information represented by the presence or absence of DNA hairpin loops protruding out of the lattice plane. Self-assembly of multiple DNA tiles around the scaffold strand was shown to result in a patterned lattice containing barcode information of 01101. We have also demonstrated the reprogramming of the system to another patterning. An inverted barcode pattern of 10010 was achieved by modifying the scaffold strands and one of the strands composing each tile. A ribbon lattice, consisting of repetitions of the barcode pattern with expected periodicity, was also constructed by the addition of sticky ends. The patterning of both classes of lattices was clearly observable via atomic force microscopy. These results represent a step toward implementation of a visual readout system capable of converting information encoded on a 1D DNA strand into a 2D form readable by advanced microscopic techniques. A functioning visual output method would not only increase the readout speed of DNA-based computers, but may also find use in other sequence identification techniques such as mutation or allele mapping.

  5. Directed nucleation assembly of DNA tile complexes for barcode-patterned lattices.

    PubMed

    Yan, Hao; LaBean, Thomas H; Feng, Liping; Reif, John H

    2003-07-08

    The programmed self-assembly of patterned aperiodic molecular structures is a major challenge in nanotechnology and has numerous potential applications for nanofabrication of complex structures and useful devices. Here we report the construction of an aperiodic patterned DNA lattice (barcode lattice) by a self-assembly process of directed nucleation of DNA tiles around a scaffold DNA strand. The input DNA scaffold strand, constructed by ligation of shorter synthetic oligonucleotides, provides layers of the DNA lattice with barcode patterning information represented by the presence or absence of DNA hairpin loops protruding out of the lattice plane. Self-assembly of multiple DNA tiles around the scaffold strand was shown to result in a patterned lattice containing barcode information of 01101. We have also demonstrated the reprogramming of the system to another patterning. An inverted barcode pattern of 10010 was achieved by modifying the scaffold strands and one of the strands composing each tile. A ribbon lattice, consisting of repetitions of the barcode pattern with expected periodicity, was also constructed by the addition of sticky ends. The patterning of both classes of lattices was clearly observable via atomic force microscopy. These results represent a step toward implementation of a visual readout system capable of converting information encoded on a 1D DNA strand into a 2D form readable by advanced microscopic techniques. A functioning visual output method would not only increase the readout speed of DNA-based computers, but may also find use in other sequence identification techniques such as mutation or allele mapping.

  6. Characterisation of the high dynamic range Large Pixel Detector (LPD) and its use at X-ray free electron laser sources

    NASA Astrophysics Data System (ADS)

    Veale, M. C.; Adkin, P.; Booker, P.; Coughlan, J.; French, M. J.; Hart, M.; Nicholls, T.; Schneider, A.; Seller, P.; Pape, I.; Sawhney, K.; Carini, G. A.; Hart, P. A.

    2017-12-01

    The STFC Rutherford Appleton Laboratory have delivered the Large Pixel Detector (LPD) for MHz frame rate imaging at the European XFEL. The detector system has an active area of 0.5 m × 0.5 m and consists of a million pixels on a 500 μm pitch. Sensors have been produced from 500 μm thick Hammamatsu silicon tiles that have been bump bonded to the readout ASIC using a silver epoxy and gold stud technique. Each pixel of the detector system is capable of measuring 105 12 keV photons per image readout at 4.5 MHz. In this paper results from the testing of these detectors at the Diamond Light Source and the Linac Coherent Light Source (LCLS) are presented. The performance of the detector in terms of linearity, spatial uniformity and the performance of the different ASIC gain stages is characterised.

  7. Development and tests on OREX vehicle thermal structure system

    NASA Astrophysics Data System (ADS)

    Yoshinaka, Toshinari; Morino, Yoshiki

    1992-08-01

    An overview of the thermal system structure development and their tests for Orbital Re-entry Experiment (OREX) vehicle, being developed as a part of H-2 Orbiting Plane (HOPE) development, is presented. The results of study on the OREX vehicle thermal structure system and concept of the system study are shown. The results of HOPE thermal structure system research were reflected to OREX in employing polyacrylonitrile tissues with conversion coating for the nose cap, Carbon-Thermal Protection System (TPS), and ceramic tile TPS for the structure. Test plans were established for material characteristics and design verifications, and flight validation for C/C (Carbon/Carbon Composite) nose cap and TPS, and gap filler, arc wind tunnel, heat insulation, and adhesion quality verification tests. Environment resistance of the C/C nose cone, C/C TPS, and ceramic tile TPS were verified and prospects of their manufacturing were obtained.

  8. Production Process for Strong, Light Ceramic Tiles

    NASA Technical Reports Server (NTRS)

    Holmquist, G. R.; Cordia, E. R.; Tomer, R. S.

    1985-01-01

    Proportions of ingredients and sintering time/temperature schedule changed. Production process for lightweight, high-strength ceramic insulating tiles for Space Shuttle more than just scaled-up version of laboratory process for making small tiles. Boron in aluminum borosilicate fibers allows fusion at points where fibers contact each other during sintering, thereby greatly strengthening tiles structure.

  9. Installation of Ceramic Tile: Residential Thin-Set Methods.

    ERIC Educational Resources Information Center

    Short, Sam

    This curriculum guide contains materials for use in teaching a course on residential thin-set methods of tile installation. Covered in the individual units are the following topics: the tile industry; basic math; tools; measurement; safety in tile setting; installation materials and guidelines for their use; floors; counter tops and backsplashes;…

  10. Flat Tile Armour Cooled by Hypervapotron Tube: a Possible Technology for ITER

    NASA Astrophysics Data System (ADS)

    Schlosser, J.; Escourbiac, F.; Merola, M.; Schedler, B.; Bayetti, P.; Missirlian, M.; Mitteau, R.; Robin-Vastra, I.

    Carbon fibre composite (CFC) flat tile armours for actively cooled plasma facing components (PFC’s) are an important challenge for controlled fusion machines. Flat tile concepts, water cooled by tubes, were studied, developed, tested and finally operated with success in Tore Supra. The components were designed for 10 MW/m2 and mock-ups were successfully fatigue tested at 15 MW/m2, 1000 cycles. For ITER, a tube-in-tile concept was developed and mock-ups sustained up to 25 MW/m2 for 1000 cycles without failure. Recently flat tile armoured mock-ups cooled by a hypervapotron tube successfully sustained a cascade failure test under a mean heat flux of 10 MW/m2 but with a doubling of the heat flux on some tiles to simulate missing tiles (500 cycles). This encouraging results lead to reconsider the limits for flat tile concept when cooled by hypervapotron (HV) tube. New tests are now scheduled to investigate these limits in regard to the ITER requirements. Experimental evidence of the concept could be gained in Tore Supra by installing a new limiter into the machine.

  11. Crystallization mosaic effect generation by superpixels

    NASA Astrophysics Data System (ADS)

    Xie, Yuqi; Bo, Pengbo; Yuan, Ye; Wang, Kuanquan

    2015-03-01

    Art effect generation from digital images using computational tools has been a hot research topic in recent years. We propose a new method for generating crystallization mosaic effects from color images. Two key problems in generating pleasant mosaic effect are studied: grouping pixels into mosaic tiles and arrangement of mosaic tiles adapting to image features. To give visually pleasant mosaic effect, we propose to create mosaic tiles by pixel clustering in feature space of color information, taking compactness of tiles into consideration as well. Moreover, we propose a method for processing feature boundaries in images which gives guidance for arranging mosaic tiles near image features. This method gives nearly uniform shape of mosaic tiles, adapting to feature lines in an esthetic way. The new approach considers both color distance and Euclidean distance of pixels, and thus is capable of giving mosaic tiles in a more pleasing manner. Some experiments are included to demonstrate the computational efficiency of the present method and its capability of generating visually pleasant mosaic tiles. Comparisons with existing approaches are also included to show the superiority of the new method.

  12. Technical note: comparing von Luschan skin color tiles and modern spectrophotometry for measuring human skin pigmentation.

    PubMed

    Swiatoniowski, Anna K; Quillen, Ellen E; Shriver, Mark D; Jablonski, Nina G

    2013-06-01

    Prior to the introduction of reflectance spectrophotometry into anthropological field research during the 1950s, human skin color was most commonly classified by visual skin color matching using the von Luschan tiles, a set of 36 standardized, opaque glass tiles arranged in a chromatic scale. Our goal was to establish a conversion formula between the tile-based color matching method and modern reflectance spectrophotometry to make historical and contemporary data comparable. Skin pigmentation measurements were taken on the forehead, inner upper arms, and backs of the hands using both the tiles and a spectrophotometer on 246 participants showing a broad range of skin pigmentation. From these data, a second-order polynomial conversion formula was derived by jackknife analysis to estimate melanin index (M-index) based on tile values. This conversion formula provides a means for comparing modern data to von Luschan tile measurements recorded in historical reports. This is particularly important for populations now extinct, extirpated, or admixed for which tile-based measures of skin pigmentation are the only data available. Copyright © 2013 Wiley Periodicals, Inc.

  13. Selenium and other elements in freshwater fishes from the irrigated San Joaquin Valley, California

    USGS Publications Warehouse

    Saiki, M.K.; Jennings, M.R.; May, T.W.

    1992-01-01

    Arsenic (As), chromium (Cr), mercury (Hg), and selenium (Se) were measured in composite whole-body samples of five fishes — bluegill (Lepomis macrochirus), common carp (Cyprinus carpio), mosquitofish (Gambusia affinis), largemouth bass (Micropterus salmoides), and Sacramento blackfish (Orthodon microlepidotus) — from the San Joaquin River system to determine if concentrations were elevated from exposure to agricultural subsurface (tile) drainage. Except for Cr, the concentrations of these elements in fishes from one or more sites were elevated; however, only Se approached concentrations that may adversely affect survival, growth, or reproduction in warm water fishes. Moreover, only Se among the four measured elements exhibited a geographic (spatial) pattern that coincided with known inflows of tile drainage to the San Joaquin River and its tributaries. Historical data from the Grassland Water District (Grasslands; a region exposed to concentrated tile drainage) suggested that concentrations of Se in fishes were at maximum during or shortly after 1984 and have been slightly lower since then. The recent decline of Se concentrations in fishes from the Grasslands could be temporary if additional acreages of irrigated lands in this portion of the San Joaquin Valley must be tile-drained to protect agricultural crops from rising groundwater tables.

  14. Application of Hilbert-Huang Transform for Improved Defect Detection in Terahertz NDE of Shuttle Tiles

    NASA Technical Reports Server (NTRS)

    Anastasi, Robert F.; Madaras, Eric I.

    2005-01-01

    Terahertz NDE is being examined as a method to inspect the adhesive bond-line of Space Shuttle tiles for defects. Terahertz signals are generated and detected, using optical excitation of biased semiconductors with femtosecond laser pulses. Shuttle tile samples were manufactured with defects that included repair regions unbond regions, and other conditions that occur in Shuttle structures. These samples were inspected with a commercial terahertz NDE system that scanned a tile and generated a data set of RF signals. The signals were post processed to generate C-scan type images that are typically seen in ultrasonic NDE. To improve defect visualization the Hilbert-Huang Transform, a transform that decomposes a signal into oscillating components called intrinsic mode functions, was applied to test signals identified as being in and out of the defect regions and then on a complete data set. As expected with this transform, the results showed that the decomposed low-order modes correspond to signal noise while the high-order modes correspond to low frequency oscillations in the signal and mid-order modes correspond to local signal oscillations. The local oscillations compare well with various reflection interfaces and the defect locations in the original signal.

  15. Upgrade of the ATLAS Tile Calorimeter Electronics

    NASA Astrophysics Data System (ADS)

    Moreno, Pablo; ATLAS Tile Calorimeter System

    2016-04-01

    The Tile Calorimeter (TileCal) is the hadronic calorimeter covering the central region of the ATLAS experiment at LHC. The TileCal readout consists of 9852 channels. The bulk of its upgrade will occur for the High Luminosity LHC phase (Phase II) where the peak luminosity will increase 5× compared to the design luminosity (1034 cm-2s-1) at center of mass energy of 14 TeV. The TileCal upgrade aims at replacing the majority of the on- and off-detector electronics to the extent that all calorimeter signals will be digitized and sent to the off-detector electronics in the counting room. To achieve the required reliability, redundancy has been introduced at different levels. Three different options are presently being investigated for the front-end electronic upgrade. Extensive test beam studies will determine which option will be selected. 10.24 Gbps optical links are used to read out all digitized data to the counting room while 4.8 Gbps down-links are used for synchronization, configuration and detector control. For the off-detector electronics a pre-processor (sROD) is being developed, which takes care of the initial trigger processing while temporarily storing the main data flow in pipeline and de-randomizer memories. Field Programmable Gate Arrays are extensively used for the logic functions off- and on-detector. One demonstrator prototype module with the new calorimeter module electronics, but still compatible with the present system, is planned to be inserted in ATLAS at the end of 2015.

  16. Supporting Tablet Configuration, Tracking, and Infection Control Practices in Digital Health Interventions: Study Protocol.

    PubMed

    Furberg, Robert D; Ortiz, Alexa M; Zulkiewicz, Brittany A; Hudson, Jordan P; Taylor, Olivia M; Lewis, Megan A

    2016-06-27

    Tablet-based health care interventions have the potential to encourage patient care in a timelier manner, allow physicians convenient access to patient records, and provide an improved method for patient education. However, along with the continued adoption of tablet technologies, there is a concomitant need to develop protocols focusing on the configuration, management, and maintenance of these devices within the health care setting to support the conduct of clinical research. Develop three protocols to support tablet configuration, tablet management, and tablet maintenance. The Configurator software, Tile technology, and current infection control recommendations were employed to develop three distinct protocols for tablet-based digital health interventions. Configurator is a mobile device management software specifically for iPhone operating system (iOS) devices. The capabilities and current applications of Configurator were reviewed and used to develop the protocol to support device configuration. Tile is a tracking tag associated with a free mobile app available for iOS and Android devices. The features associated with Tile were evaluated and used to develop the Tile protocol to support tablet management. Furthermore, current recommendations on preventing health care-related infections were reviewed to develop the infection control protocol to support tablet maintenance. This article provides three protocols: the Configurator protocol, the Tile protocol, and the infection control protocol. These protocols can help to ensure consistent implementation of tablet-based interventions, enhance fidelity when employing tablets for research purposes, and serve as a guide for tablet deployments within clinical settings.

  17. Preferential flow estimates to an agricultural tile drain with implications for glyphosate transport

    USGS Publications Warehouse

    Stone, W.W.; Wilson, J.T.

    2006-01-01

    Agricultural subsurface drains, commonly referred to as tile drains, are potentially significant pathways for the movement of fertilizers and pesticides to streams and ditches in much of the Midwest. Preferential flow in the unsaturated zone provides a route for water and solutes to bypass the soil matrix and reach tile drains faster than predicted by traditional displacement theory. This paper uses chloride concentrations to estimate preferential flow contributions to a tile drain during two storms in May 2004. Chloride, a conservative anion, was selected as the tracer because of differences in chloride concentrations between the two sources of water to the tile drain, preferential and matrix flow. A strong correlation between specific conductance and chloride concentration provided a mechanism to estimate chloride concentrations in the tile drain throughout the storm hydrographs. A simple mixing analysis was used to identify the preferential flow component of the storm hydrograph. During two storms, preferential flow contributed 11 and 51% of total storm tile drain flow; the peak contributions, 40 and 81%, coincided with the peak tile drain flow. Positive relations between glyphosate [N-(phosphonomethyl)glycine] concentrations and preferential flow for the two storms suggest that preferential flow is an important transport pathway to the tile drain. ?? ASA, CSSA, SSSA.

  18. Reuse of solid petroleum waste in the manufacture of porcelain stoneware tile.

    PubMed

    Pinheiro, B C A; Holanda, J N F

    2013-03-30

    This study investigates the incorporation of solid petroleum waste as raw material into a porcelain stoneware tile body, in replacement to natural kaolin material by up to 5 wt.%. Tile formulations containing solid petroleum waste were pressed and fired at 1240 °C by using a fast-firing cycle. The tile pieces were tested to determine their properties (linear shrinkage, water absorption, apparent density, and flexural strength), sintered microstructure, and leaching toxicity. The results therefore indicated that the growing addition of solid petroleum waste into tile formulations leads to a decrease of linear shrinkage, apparent density, and flexural strength, and to an increase of water absorption of the produced tile materials. It was also found that the replacement of kaolin with solid petroleum waste, in the range up to 2.5 wt.%, allows the production of porcelain stoneware tile (group BIa, ISO 13006 standard). All concentrations of Ag, As, Ba, Cd, Cr (total), Hg, and Pb of the fired porcelain stoneware tile pieces in the leachate comply with the current regulatory limits. These results indicate that the solid petroleum waste could be used for high-quality porcelain stoneware tile production, thus giving rise to a new possibility for an environmentally friendly management of this abundant waste. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Tile Drainage Management Influences on Surface-Water and Groundwater Quality following Liquid Manure Application.

    PubMed

    Frey, Steven K; Topp, Ed; Ball, Bonnie R; Edwards, Mark; Gottschall, Natalie; Sunohara, Mark; Zoski, Erin; Lapen, David R

    2013-01-01

    This study investigated the potential for controlled tile drainage (CD) to reduce bacteria and nutrient loading to surface water and groundwater from fall-season liquid manure application (LMA) on four macroporous clay loam plots, of which two had CD and two had free-draining (FD) tiles. Rhodamine WT (RWT) was mixed into the manure and monitored in the tile water and groundwater following LMA. Tile water and groundwater quality were influenced by drainage management. Following LMA on the FD plots, RWT, nutrients, and bacteria moved rapidly via tiles to surface water; at the CD plots, tiles did not flow until the first post-LMA rainfall, so the immediate risk of LMA-induced contamination of surface water was abated. During the 36-d monitoring period, flow-weighted average specific conductance, redox potential, and turbidity, as well as total Kjeldahl N (TKN), total P (TP), NH-N, reactive P, and RWT concentrations, were higher in the CD tile effluent; however, because of lower tile discharge from the CD plots, there was no significant ( ≤ 0.05) difference in surface water nutrient and RWT loading between the CD and FD plots when all tiles were flowing. The TKN, TP, and RWT concentrations in groundwater also tended to be higher at the CD plots. Bacteria behaved differently than nutrients and RWT, with no significant difference in total coliform, , fecal coliform, fecal streptococcus, and concentrations between the CD and FD tile effluent; however, for all but , hourly loading was higher from the FD plots. Results indicate that CD has potential for mitigating bacteria movement to surface water. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  20. Comparing the predictive value of the pelvic ring injury classification systems by Tile and by Young and Burgess.

    PubMed

    Osterhoff, Georg; Scheyerer, Max J; Fritz, Yannick; Bouaicha, Samy; Wanner, Guido A; Simmen, Hans-Peter; Werner, Clément M L

    2014-04-01

    Radiology-based classifications of pelvic ring injuries and their relevance for the prognosis of morbidity and mortality are disputed in the literature. The purpose of this study was to evaluate potential differences between the pelvic ring injury classification systems by Tile and by Young and Burgess with regard to their predictive value on mortality, transfusion/infusion requirement and concomitant injuries. Two-hundred-and-eighty-five consecutive patients with pelvic ring fractures were analyzed for mortality within 30 days after admission, number of blood units and total volume of fluid infused during the first 24h after trauma, the Abbreviated Injury Severity (AIS) scores for head, chest, spine, abdomen and extremities as a function of the Tile and the Young-Burgess classifications. There was no significant relationship between occurrence of death and fracture pattern but a significant relationship between fracture pattern and need for blood units/total fluid volume for Tile (p<.001/p<.001) and Young-Burgess (p<.001/p<.001). In both classifications, open book fractures were associated with more fluid requirement and more severe injuries of the abdomen, spine and extremities (p<.05). When divided into the larger subgroups "partially stable" and "unstable", unstable fractures were associated with a higher mortality rate in the Young-Burgess system (p=.036). In both classifications, patients with unstable fractures required significantly more blood transfusions (p<.001) and total fluid infusion (p<.001) and higher AIS scores. In this first direct comparison of both classifications, we found no clinical relevant differences with regard to their predictive value on mortality, transfusion/infusion requirement and concomitant injuries. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. High Resolution Millimeter Wave Inspecting of the Orbiter Acreage Heat Tiles of the Space Shuttle

    NASA Technical Reports Server (NTRS)

    Case, J. T.; Khakovsky, S.; Zoughi, r.; Hepburn, F.

    2007-01-01

    Presence of defects such as disbonds, delaminations, impact damage, in thermal protection systems can significantly reduce safety of the Space Shuttle and its crew. The physical cause of Space Shuttle Columbia's catastrophic failure was a breach in its thermal protection system, caused by a piece of external tank insulating foam separating from the external tank and striking the leading edge of the left wing of the orbiter. There is an urgent need for a rapid, robust and life-circle oriented nondestructive testing (NDT) technique capable of inspecting the external tank insulating foam as well as the orbiter's protective (acreage) heat tiles and its fuselage prior and subsequent to a launch. Such a comprehensive inspection technique enables NASA to perform life-cycle inspection on critical components of the orbiter and its supporting hardware. Consequently, NASA Marshall Space Flight Center initiated an investigation into several potentially viable NDT techniques for this purpose. Microwave and millimeter wave NDT methods have shown great potential to achieve these goals. These methods have been successfully used to produce images of the interior of various complex, thick and thin external tank insulating foam structures for real focused reflectometer at operating frequency from 50-100 GHz and for synthetic aperture techniques at Ku-band (12-18 GHz) and K-band (18-26 GHz). Preliminary results of inspecting heat tile specimens show that increasing resolution of the measurement system is an important issue. This paper presents recent results of an investigation for the purpose of detecting anomalies such as debonds and corrosion in metal substrate in complex multi-sectioned protective heat tile specimens using a real focused 150 GHz (D-band) reflectometer and wide-band millimeter wave holography at 33-50, GHz (Q-band).

  2. Simulating Sustainable P Management Practices in Tile-Drained Landscapes of Central Ohio Using the Agricultural Policy Environmental Extender (APEX)

    NASA Astrophysics Data System (ADS)

    Ford, W. I., III; King, K.; Williams, M.

    2014-12-01

    Despite extensive application of conservation practices to minimize sediment P delivery to streams, hypoxic conditions and harmful algal blooms persist in receiving water bodies. Tile-drainage networks are a focal point for reducing soluble P in the food-producing Midwestern United States in that they promote higher connectivity between upland soils and stream channels which decreases soil contact time, and biogeochemical alterations. A critical next step to reduce the environmental impact and maintain sustainable agriculture is to implement best management practices (BMPs) under a holistic framework that considers adverse effects to water resources and crop production, while maintaining economic feasibility. The objective of this study was to apply a robust numerical model, the Agricultural Policy Environmental Extender (APEX), in a tile-drained landscape in Central Ohio in order to evaluate the effectiveness of a suite of BMPs on soluble and particulate P delivery to stream channels. The model was applied and evaluated at two adjacent edge-of-field sites with similar soil, topographic and management characteristics (except for tillage and tile installation on the south field in 2012, preceded by more than 20 years of no-till operations). Three years of daily discharge, total suspended solids, soluble P, soluble N (NO3 and NH4), total P, total N, and crop yields were utilized to verify the model performance. Prevalent BMPs simulated within the modeling framework included drainage water management, tillage and crop rotations, the 4Rs framework (right fertilizer source, rate, time, and placement), and bioreactors. Results of the study quantify the ability of the numerical model to simulate hydrology and P transport for surface runoff and subsurface tile drainage and highlight modifications that improve model performance. Further, results highlight BMPs that effectively reduce P loads to streams while maintaining crop yields, which can later be used to inform BMPs implemented at edge-of-field sites in Ohio. While beyond the scope of this study, future work aims to investigate the sustainability of BMPs under dynamic climate conditions and across watershed gradients.

  3. The TeleEngineering Toolkit Software Reference Manual

    DTIC Science & Technology

    2007-08-01

    arrangement of windows. ................................................................. 74 Figure 6.26. Tile arrangement of windows...Level 1, and Commercial Satellite Imagery (CSIL). The Toolkit also supports USGS Digital Orthophoto Quadrangle, scanned georectified maps, and various...in a cascading manner as shown in Figure 6.25. Tile The Tile tool in the Window menu will arrange the windows in a tiled manner as shown in

  4. Handmade Tile Mosaics

    ERIC Educational Resources Information Center

    Keeler, Rusty

    2007-01-01

    Just like the classroom, children's outdoor environments should be filled with artistic creations that add sparkle and imagination to the space. One of the author's favorite ways to add art to the outdoors is by installing a mosaic mural of child-made tiles. The process of making the tiles is fun for all; each tile is a charming work of art in…

  5. 21. TILES OF THE NEW WORLD PANEL, NORTH WALL OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    21. TILES OF THE NEW WORLD PANEL, NORTH WALL OF THE INDIAN HOUSE. THE RELIEF BROCADE TILES ILLUSTRATE SCENES OF NATIVE AMERICAN HISTORY AND CULTURE, AND THE EARLY EUROPEAN EXPLORATION OF THE NEW WORLD. - Moravian Pottery & Tile Works, Southwest side of State Route 313 (Swamp Road), Northwest of East Court Street, Doylestown, Bucks County, PA

  6. At-TAX: a whole genome tiling array resource for developmental expression analysis and transcript identification in Arabidopsis thaliana

    PubMed Central

    Laubinger, Sascha; Zeller, Georg; Henz, Stefan R; Sachsenberg, Timo; Widmer, Christian K; Naouar, Naïra; Vuylsteke, Marnik; Schölkopf, Bernhard; Rätsch, Gunnar; Weigel, Detlef

    2008-01-01

    Gene expression maps for model organisms, including Arabidopsis thaliana, have typically been created using gene-centric expression arrays. Here, we describe a comprehensive expression atlas, Arabidopsis thaliana Tiling Array Express (At-TAX), which is based on whole-genome tiling arrays. We demonstrate that tiling arrays are accurate tools for gene expression analysis and identified more than 1,000 unannotated transcribed regions. Visualizations of gene expression estimates, transcribed regions, and tiling probe measurements are accessible online at the At-TAX homepage. PMID:18613972

  7. Tethers as Debris: Simulating Impacts of Tether Fragments on Shuttle Tiles

    NASA Technical Reports Server (NTRS)

    Evans, Steven W.

    2004-01-01

    The SPHC hydrodynamic code was used to simulate impacts of Kevlar and aluminum projectiles on a model of the LI-900 type insulating tiles used on Space Shuffle Orbiters The intent was to examine likely damage that such tiles might experience if impacted by orbital debris consisting of tether fragments. Projectile speeds ranged from 300 meters per second to 10 kilometers per second. Damage is characterized by penetration depth, tile surface-hole diameter, tile body-cavity diameter, coating fracture diameter, tether and cavity wall material phases, and deformation of the aluminum backwall.

  8. Multilayer Impregnated Fibrous Thermal Insulation Tiles

    NASA Technical Reports Server (NTRS)

    Tran, Huy K.; Rasky, Daniel J.; Szalai, Christine e.; Hsu, Ming-ta; Carroll, Joseph A.

    2007-01-01

    The term "secondary polymer layered impregnated tile" ("SPLIT") denotes a type of ablative composite-material thermal- insulation tiles having engineered, spatially non-uniform compositions. The term "secondary" refers to the fact that each tile contains at least two polymer layers wherein endothermic reactions absorb considerable amounts of heat, thereby helping to prevent overheating of an underlying structure. These tiles were invented to afford lighter-weight alternatives to the reusable thermal-insulation materials heretofore variously used or considered for use in protecting the space shuttles and other spacecraft from intense atmospheric-entry heating.

  9. KSC-08pd1967

    NASA Image and Video Library

    2008-07-14

    CAPE CANAVERAL, Fla. – In the tile shop at NASA's Kennedy Space Center, a worker reaches for the door to close the oven with the Boeing Replacement Insulation 18, or BRI-18, tile inside. The tile will be baked at 2,200 degrees Fahrenheit to cure the ceramic coating, part of the process to prepare the tiles for installation on space shuttles. BRI-18 is the strongest material used for thermal insulation on the orbiters and, when coated to produce toughened unipiece fibrous insulation, provides a tile with extremely high-impact resistance. It is replacing other tiles on areas of the vehicle where impact risk is high, such as the landing gear doors, the wing leading edge and the external tank doors. Photo credit: NASA/Jim Grossmann

  10. KSC-08pd1965

    NASA Image and Video Library

    2008-07-14

    CAPE CANAVERAL, Fla. – In the tile shop at NASA's Kennedy Space Center, a worker is ready to place a Boeing Replacement Insulation 18, or BRI-18, tile in the oven. The tile will be baked at 2,200 degrees Fahrenheit to cure the ceramic coating, part of the process to prepare the tiles for installation on space shuttles. BRI-18 is the strongest material used for thermal insulation on the orbiters and, when coated to produce toughened unipiece fibrous insulation, provides a tile with extremely high-impact resistance. It is replacing other tiles on areas of the vehicle where impact risk is high, such as the landing gear doors, the wing leading edge and the external tank doors. Photo credit: NASA/Jim Grossmann

  11. Ion beam sputter target and method of manufacture

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Higdon, Clifton; Elmoursi, Alaa A.; Goldsmith, Jason

    A target for use in an ion beam sputtering apparatus made of at least two target tiles where at least two of the target tiles are made of different chemical compositions and are mounted on a main tile and geometrically arranged on the main tile to yield a desired chemical composition on a sputtered substrate. In an alternate embodiment, the tiles are of varied thickness according to the desired chemical properties of the sputtered film. In yet another alternate embodiment, the target is comprised of plugs pressed in a green state which are disposed in cavities formed in a mainmore » tile also formed in a green state and the assembly can then be compacted and then sintered.« less

  12. KSC-2011-1474

    NASA Image and Video Library

    2011-02-17

    CAPE CANAVERAL, Fla. -- In Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida, a thermal protection system technician inspects the area on space shuttle Atlantis' underside before a heat shield tile is installed. The tiles are part of the Orbiter Thermal Protection System that protects the shuttle against temperatures as high as 3,000 degrees Fahrenheit, which are produced during descent for landing. Atlantis is being prepared for the STS-135 mission, which will carry the Raffaello multi-purpose logistics module packed with supplies, logistics and spare parts to the International Space Station. STS-135 is targeted to launch June 28, and will be the last flight for the Space Shuttle Program. Photo credit: NASA/Jack Pfaller

  13. KSC-2011-1473

    NASA Image and Video Library

    2011-02-17

    CAPE CANAVERAL, Fla. -- In Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida, a thermal protection system technician applies a bonding agent to an area on space shuttle Atlantis' underside where a heat shield tile will be installed. The tiles are part of the Orbiter Thermal Protection System that protects the shuttle against temperatures as high as 3,000 degrees Fahrenheit, which are produced during descent for landing. Atlantis is being prepared for the STS-135 mission, which will carry the Raffaello multi-purpose logistics module packed with supplies, logistics and spare parts to the International Space Station. STS-135 is targeted to launch June 28, and will be the last flight for the Space Shuttle Program. Photo credit: NASA/Jack Pfaller

  14. KSC-2011-1472

    NASA Image and Video Library

    2011-02-17

    CAPE CANAVERAL, Fla. -- In Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida, a thermal protection system technician applies a bonding agent to an area on space shuttle Atlantis' underside where a heat shield tile will be installed. The tiles are part of the Orbiter Thermal Protection System that protects the shuttle against temperatures as high as 3,000 degrees Fahrenheit, which are produced during descent for landing. Atlantis is being prepared for the STS-135 mission, which will carry the Raffaello multi-purpose logistics module packed with supplies, logistics and spare parts to the International Space Station. STS-135 is targeted to launch June 28, and will be the last flight for the Space Shuttle Program. Photo credit: NASA/Jack Pfaller

  15. KSC-2011-1475

    NASA Image and Video Library

    2011-02-17

    CAPE CANAVERAL, Fla. -- In Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida, a thermal protection system technician installs a gap filler in the area on space shuttle Atlantis' underside before a heat shield tile is installed. The tiles are part of the Orbiter Thermal Protection System that protects the shuttle against temperatures as high as 3,000 degrees Fahrenheit, which are produced during descent for landing. Atlantis is being prepared for the STS-135 mission, which will carry the Raffaello multi-purpose logistics module packed with supplies, logistics and spare parts to the International Space Station. STS-135 is targeted to launch June 28, and will be the last flight for the Space Shuttle Program. Photo credit: NASA/Jack Pfaller

  16. Nonablative lightweight thermal protection system for Mars Aeroflyby Sample collection mission

    NASA Astrophysics Data System (ADS)

    Suzuki, Toshiyuki; Aoki, Takuya; Ogasawara, Toshio; Fujita, Kazuhisa

    2017-07-01

    In this study, the concept of a nonablative lightweight thermal protection system (NALT) were proposed for a Mars exploration mission currently under investigation in Japan. The NALT consists of a carbon/carbon (C/C) composite skin, insulator tiles, and a honeycomb sandwich panel. Basic thermal characteristics of the NALT were obtained by conducting heating tests in high-enthalpy facilities. Thermal conductivity values of the insulator tiles as well as the emissivity values of the C/C skin were measured to develop a numerical analysis code for predicting NALT's thermal performance in flight environments. Finally, a breadboard model of a 600-mm diameter NALT aeroshell was developed and qualified through vibration and thermal vacuum tests.

  17. KSC-2011-1400

    NASA Image and Video Library

    2011-02-08

    CAPE CANAVERAL, Fla. -- In Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida, a thermal protection system technician prepares the surface under space shuttle Atlantis before installing a heat shield tile. The tiles are part of the Orbiter Thermal Protection System, thermal shields to protect against temperatures as high as 3,000 degrees Fahrenheit, which are produced during descent for landing. Atlantis is being prepared for the STS-135 mission, which will deliver the Raffaello multi-purpose logistics module packed with supplies, logistics and spare parts to the International Space Station. STS-135 is targeted to launch June 28, and will be the last spaceflight for the Space Shuttle Program. Photo credit: NASA/Jack Pfaller

  18. KSC-2011-1470

    NASA Image and Video Library

    2011-02-17

    CAPE CANAVERAL, Fla. -- In Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida, a thermal protection system technician is preparing to work on replacing some of space shuttle Atlantis' heat shield tiles. The tiles are part of the Orbiter Thermal Protection System that protects the shuttle against temperatures as high as 3,000 degrees Fahrenheit, which are produced during descent for landing. Atlantis is being prepared for the STS-135 mission, which will carry the Raffaello multi-purpose logistics module packed with supplies, logistics and spare parts to the International Space Station. STS-135 is targeted to launch June 28, and will be the last flight for the Space Shuttle Program. Photo credit: NASA/Jack Pfaller

  19. KSC-2011-1399

    NASA Image and Video Library

    2011-02-08

    CAPE CANAVERAL, Fla. -- In Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida, a thermal protection system technician is ready to work on replacing some of space shuttle Atlantis' heat shield tiles. The tiles are part of the Orbiter Thermal Protection System, thermal shields to protect against temperatures as high as 3,000 degrees Fahrenheit, which are produced during descent for landing. Atlantis is being prepared for the STS-135 mission, which will deliver the Raffaello multi-purpose logistics module packed with supplies, logistics and spare parts to the International Space Station. STS-135 is targeted to launch June 28, and will be the last spaceflight for the Space Shuttle Program. Photo credit: NASA/Jack Pfaller

  20. KSC-2011-1403

    NASA Image and Video Library

    2011-02-08

    CAPE CANAVERAL, Fla. -- In Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida, a thermal protection system technician secures a newly installed heat shield tile in place under space shuttle Atlantis. The tiles are part of the Orbiter Thermal Protection System, thermal shields to protect against temperatures as high as 3,000 degrees Fahrenheit, which are produced during descent for landing. Atlantis is being prepared for the STS-135 mission, which will deliver the Raffaello multi-purpose logistics module packed with supplies, logistics and spare parts to the International Space Station. STS-135 is targeted to launch June 28, and will be the last spaceflight for the Space Shuttle Program. Photo credit: NASA/Jack Pfaller

  1. KSC-2011-1476

    NASA Image and Video Library

    2011-02-17

    CAPE CANAVERAL, Fla. -- In Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida, a thermal protection system technician closely inspects a heat shield tile for space shuttle Atlantis before securing it into position. The tiles are part of the Orbiter Thermal Protection System that protects the shuttle against temperatures as high as 3,000 degrees Fahrenheit, which are produced during descent for landing. Atlantis is being prepared for the STS-135 mission, which will carry the Raffaello multi-purpose logistics module packed with supplies, logistics and spare parts to the International Space Station. STS-135 is targeted to launch June 28, and will be the last flight for the Space Shuttle Program. Photo credit: NASA/Jack Pfaller

  2. KSC-2011-1401

    NASA Image and Video Library

    2011-02-08

    CAPE CANAVERAL, Fla. -- In Orbiter Processing Facility-1 at NASA's Kennedy Space Center in Florida, a thermal protection system technician prepares the surface under space shuttle Atlantis before installing a heat shield tile. The tiles are part of the Orbiter Thermal Protection System, thermal shields to protect against temperatures as high as 3,000 degrees Fahrenheit, which are produced during descent for landing. Atlantis is being prepared for the STS-135 mission, which will deliver the Raffaello multi-purpose logistics module packed with supplies, logistics and spare parts to the International Space Station. STS-135 is targeted to launch June 28, and will be the last spaceflight for the Space Shuttle Program. Photo credit: NASA/Jack Pfaller

  3. Boeing's High Voltage Solar Tile Test Results

    NASA Astrophysics Data System (ADS)

    Reed, Brian J.; Harden, David E.; Ferguson, Dale C.; Snyder, David B.

    2002-10-01

    Real concerns of spacecraft charging and experience with solar array augmented electrostatic discharge arcs on spacecraft have minimized the use of high voltages on large solar arrays despite numerous vehicle system mass and efficiency advantages. Boeing's solar tile (patent pending) allows high voltage to be generated at the array without the mass and efficiency losses of electronic conversion. Direct drive electric propulsion and higher power payloads (lower spacecraft weight) will benefit from this design. As future power demand grows, spacecraft designers must use higher voltage to minimize transmission loss and power cable mass for very large area arrays. This paper will describe the design and discuss the successful test of Boeing's 500-Volt Solar Tile in NASA Glenn's Tenney chamber in the Space Plasma Interaction Facility. The work was sponsored by NASA's Space Solar Power Exploratory Research and Technology (SERT) Program and will result in updated high voltage solar array design guidelines being published.

  4. Boeing's High Voltage Solar Tile Test Results

    NASA Technical Reports Server (NTRS)

    Reed, Brian J.; Harden, David E.; Ferguson, Dale C.; Snyder, David B.

    2002-01-01

    Real concerns of spacecraft charging and experience with solar array augmented electrostatic discharge arcs on spacecraft have minimized the use of high voltages on large solar arrays despite numerous vehicle system mass and efficiency advantages. Boeing's solar tile (patent pending) allows high voltage to be generated at the array without the mass and efficiency losses of electronic conversion. Direct drive electric propulsion and higher power payloads (lower spacecraft weight) will benefit from this design. As future power demand grows, spacecraft designers must use higher voltage to minimize transmission loss and power cable mass for very large area arrays. This paper will describe the design and discuss the successful test of Boeing's 500-Volt Solar Tile in NASA Glenn's Tenney chamber in the Space Plasma Interaction Facility. The work was sponsored by NASA's Space Solar Power Exploratory Research and Technology (SERT) Program and will result in updated high voltage solar array design guidelines being published.

  5. Orbiter Return-To-Flight Entry Aeroheating

    NASA Technical Reports Server (NTRS)

    Campbell, Charles H.; Anderson, Brian; Bourland, Gary; Bouslog, Stan; Cassady, Amy; Horvath, Tom; Berry, Scott A.; Gnoffo, Peter; Wood, Bill; Reuther, James; hide

    2006-01-01

    The Columbia accident on February 1, 2003 began an unprecedented level of effort within the hypersonic aerothermodynamic community to support the Space Shuttle Program. During the approximately six month time frame of the primary Columbia Accident Investigation Board activity, many technical disciplines were involved in a concerted effort to reconstruct the last moments of the Columbia and her crew, and understand the critical events that led to that loss. Significant contributions to the CAIB activity were made by the hypersonic aerothermodynamic community(REF CAIB) in understanding the re-entry environments that led to the propagation of an ascent foam induced wing leading edge damage to a subsequent breech of the wing spar of Columbia, and the subsequent breakup of the vehicle. A core of the NASA hypersonic aerothermodynamics team that was involved in the CAIB investigation has been combined with the United Space Alliance and Boeing Orbiter engineering team in order to position the Space Shuttle Program with a process to perform in-flight Thermal Protection System damage assessments. This damage assessment process is now part of the baselined plan for Shuttle support, and is a direct out-growth of the Columbia accident and NASAs response. Multiple re-entry aeroheating tools are involved in this damage assessment process, many of which have been developed during the Return To Flight activity. In addition, because these aeroheating tools are part of an overall damage assessment process that also involves the thermal and stress analyses community, in addition to a much broader mission support team, an integrated process for performing the damage assessment activities has been developed by the Space Shuttle Program and the Orbiter engineering community. Several subsets of activity in the Orbiter aeroheating communities support to the Return To Flight effort have been described in previous publications (CFD?, Cavity Heating? Any BLT? Grid Generation?). This work will provide a description of the integrated process utilized to perform Orbiter tile damage assessment, and in particular will seek to provide a description of the integrated aeroheating tools utilized to perform these assessments. Individual aeroheating tools will be described which provide the nominal re-entry heating environment characterization for the Orbiter, the heating environments for tile damage, heating effects due to exposed Thermal Protection System substrates, the application of Computational Fluid Dynamics for the description of tile cavity heating, and boundary layer transition prediction. This paper is meant to provide an overall view of the integrated aeroheating assessment process for tile damage assessment as one of a sequence of papers on the development of the boundary layer transition prediction capability in support of Space Shuttle Return To Flight efforts.

  6. Evaluation of conductive concrete for anti-static flooring applications

    NASA Astrophysics Data System (ADS)

    Yehia, Sherif; Qaddoumi, Nasser; Hassan, Mohamed; Swaked, Bassam

    2015-04-01

    Static electricity, exchange of electrons, and retention of charge between any two materials due to contact and separation are affected by the condition of the materials being nonconductive or insulated from ground. Several work environments, such as electronics industry, hospitals, offices, and computer rooms all require electro-static discharge (ESD) mitigation. Carpet Tile, Carpet Broadloom, Vinyl Tile, Vinyl sheet, Epoxy and Rubber are examples of existing flooring systems in the market. However, each system has its advantages and limitations. Conductive concrete is a relatively new material technology developed to achieve high electrical conductivity and high mechanical strength. The conductive concrete material can be an economical alternative for these ESD flooring systems. In this paper, the effectiveness of conductive concrete as an anti-static flooring system was evaluated. The initial results indicated that the proposed conductive concrete flooring and ground system met the acceptance criteria stated by ASTM F150.

  7. ARC-1980-AC80-0107-8

    NASA Image and Video Library

    1980-02-06

    ROCKWELL INTERNATIONAL TECHNICIANS MOUNT SOME OF THE NEARLY 8,000 CERAMIC-COATED TILES THAT REMAIN TO BE INSTALLED ON THE EXTERNAL SURFACES OF THE SPACE SHUTTLE ORBITER COLUMBIA TO COMPLETE THE THERMAL PROTECTION SYSTEM THAT WILL ABSORB THE INTENSE HEAT OF REENTERING THE EARTH'S ATMOSPHERE AFTER A MISSION IN SPACE. TILE INSTALLATION IS DONE ON AN AROUND-THE-CLOCK BASIS IN THE ORBITER PROCESSING FACILITY WHERE COLUMBIA, THE FIRST IN A NEW BREED OF MANNED, REUSABLE SPACECRAFT, IS BEING READIED FOR THE FIRST LAUNCH OF THE SPACE SHUTTLE LATER THIS YEAR.

  8. ARC-1980-AC80-0107-9

    NASA Image and Video Library

    1980-02-06

    ROCKWELL INTERNATIONAL TECHNICIANS MOUNT SOME OF THE NEARLY 8,000 CERAMIC-COATED TILES THAT REMAIN TO BE INSTALLED ON THE EXTERNAL SURFACES OF THE SPACE SHUTTLE ORBITER COLUMBIA TO COMPLETE THE THERMAL PROTECTION SYSTEM THAT WILL ABSORB THE INTENSE HEAT OF REENTERING THE EARTH'S ATMOSPHERE AFTER A MISSION IN SPACE. TILE INSTALLATION IS DONE ON AN AROUND-THE-CLOCK BASIS IN THE ORBITER PROCESSING FACILITY WHERE COLUMBIA, THE FIRST IN A NEW BREED OF MANNED, REUSABLE SPACECRAFT, IS BEING READIED FOR THE FIRST LAUNCH OF THE SPACE SHUTTLE LATER THIS YEAR.

  9. Application of Fuzzy State Aggregation and Policy Hill Climbing to Multi-Agent Systems in Stochastic Environments

    DTIC Science & Technology

    2006-03-01

    represented by the set of tiles that it lies in. A variation on tile coding is Berenji and Vengerov’s [4, 5] use of fuzzy state aggregation (FSA) as a means...approximation with Q-learning is not a new or unusual concept [1, 3]. Berenji and Vengerov [4, 5] advanced this work in their application of Q-learning and... Berenji and Vengerov [4, 5]. The simplified Tileworld consists of agents, reward spikes, and deformations. The agent must select which reward to pursue

  10. Highly Symmetric and Congruently Tiled Meshes for Shells and Domes

    PubMed Central

    Rasheed, Muhibur; Bajaj, Chandrajit

    2016-01-01

    We describe the generation of all possible shell and dome shapes that can be uniquely meshed (tiled) using a single type of mesh face (tile), and following a single meshing (tiling) rule that governs the mesh (tile) arrangement with maximal vertex, edge and face symmetries. Such tiling arrangements or congruently tiled meshed shapes, are frequently found in chemical forms (fullerenes or Bucky balls, crystals, quasi-crystals, virus nano shells or capsids), and synthetic shapes (cages, sports domes, modern architectural facades). Congruently tiled meshes are both aesthetic and complete, as they support maximal mesh symmetries with minimal complexity and possess simple generation rules. Here, we generate congruent tilings and meshed shape layouts that satisfy these optimality conditions. Further, the congruent meshes are uniquely mappable to an almost regular 3D polyhedron (or its dual polyhedron) and which exhibits face-transitive (and edge-transitive) congruency with at most two types of vertices (each type transitive to the other). The family of all such congruently meshed polyhedra create a new class of meshed shapes, beyond the well-studied regular, semi-regular and quasi-regular classes, and their duals (platonic, Catalan and Johnson). While our new mesh class is infinite, we prove that there exists a unique mesh parametrization, where each member of the class can be represented by two integer lattice variables, and moreover efficiently constructable. PMID:27563368

  11. 29 CFR 570.64 - Occupations involved in the manufacture of brick, tile, and kindred products (Order 13).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 3 2011-07-01 2011-07-01 false Occupations involved in the manufacture of brick, tile, and... Detrimental to Their Health or Well-Being § 570.64 Occupations involved in the manufacture of brick, tile, and... term clay construction products shall mean the following clay products: Brick, hollow structural tile...

  12. 29 CFR 570.64 - Occupations involved in the manufacture of brick, tile, and kindred products (Order 13).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 3 2013-07-01 2013-07-01 false Occupations involved in the manufacture of brick, tile, and... Detrimental to Their Health or Well-Being § 570.64 Occupations involved in the manufacture of brick, tile, and... term clay construction products shall mean the following clay products: Brick, hollow structural tile...

  13. 29 CFR 570.64 - Occupations involved in the manufacture of brick, tile, and kindred products (Order 13).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 3 2012-07-01 2012-07-01 false Occupations involved in the manufacture of brick, tile, and... Detrimental to Their Health or Well-Being § 570.64 Occupations involved in the manufacture of brick, tile, and... term clay construction products shall mean the following clay products: Brick, hollow structural tile...

  14. 90. TILES OF THE NEW WORLD PANEL, NORTH WALL OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    90. TILES OF THE NEW WORLD PANEL, NORTH WALL OF THE INDIAN HOUSE. THE RELIEF BROCADE TILES ILLUSTRATE SCENES OF NATIVE AMERICAN HISTORY AND CULTURE, AND THE EARLY EUROPEAN EXPLORATION OF THE NEW WORLD. SAME VIEW AS PA-107-21. - Moravian Pottery & Tile Works, Southwest side of State Route 313 (Swamp Road), Northwest of East Court Street, Doylestown, Bucks County, PA

  15. 29 CFR 570.64 - Occupations involved in the manufacture of brick, tile, and kindred products (Order 13).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 3 2014-07-01 2014-07-01 false Occupations involved in the manufacture of brick, tile, and... Detrimental to Their Health or Well-Being § 570.64 Occupations involved in the manufacture of brick, tile, and... term clay construction products shall mean the following clay products: Brick, hollow structural tile...

  16. 77 FR 15369 - Mobility Fund Phase I Auction GIS Data of Potentially Eligible Census Blocks

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-15

    ....fcc.gov/auctions/901/ , are the following: Downloadable shapefile Web mapping service MapBox map tiles... GIS software allows you to add this service as a layer to your session or project. 6. MapBox map tiles are cached map tiles of the data. With this open source software approach, these image tiles can be...

  17. 29 CFR 570.64 - Occupations involved in the manufacture of brick, tile, and kindred products (Order 13).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Occupations involved in the manufacture of brick, tile, and... Detrimental to Their Health or Well-Being § 570.64 Occupations involved in the manufacture of brick, tile, and... term clay construction products shall mean the following clay products: Brick, hollow structural tile...

  18. Multitracer Study of Flow to Tile Drains in Irrigated Macroporous Soil

    NASA Astrophysics Data System (ADS)

    Bishop, J. M.; Callaghan, M. V.; Cey, E.; Bentley, L. R.

    2010-12-01

    Multiple tracer experiments have been conducted to test the effectiveness of using irrigation along with a tile drain system for salt remediation in west central Alberta, Canada. The experiments were designed to characterize the shallow flow system as part of a salt flushing pilot study and to determine the role of macroporosity in groundwater flow and transport. Soils at the site are primarily silty glaciolacustrine material underlain by a relatively impermeable till layer at approximately 2.5 m below ground surface. A 20 m by 20 m infiltration test plot is underlain by two tile drains at 2 m depth that are separated by 10 m. The test plot contains a drip irrigation system and has been irrigated regularly in the summer months over the past three seasons (2008-2010). Two reportedly conservative tracers, 2,6-difluorobenzoic acid [2,6-DFBA] and pentafluorobenzoic acid [PFBA], have been used on the plot and the pre-existing soil salinity was also used as a tracer. In August of 2009 a 2,6-DFBA solution (865g/L) was applied to the surface of the plot. Irrigation of the study plot continued after tracer application on a schedule that averaged roughly 12mm/day, applied 3 days a week. During the 2010 field season, a PFBA solution (at 4.2 g/L) was injected into two separate monitoring wells. One monitoring well is situated 0.5 m directly above the north tile drain (in which samples were collected regularly). The other well is situated at 2 m depth in the center of the study plot and samples were collected from a down gradient well. Tracer concentrations in the subsurface were monitored through sampling of tile drain effluent and monitoring wells in and around the plot, in addition to soil core extractions taken at several locations within the test plot at the end of the 2009 field season. Initial breakthrough of the DFBA in the tile drains occurred 24 hours after application and remained in all subsequent water samples at concentrations of 2 to 6 mg/L. Results from the DFBA analysis showed that the tiles are highly affected by the lateral and vertical contributions to the drains. Distribution of the DFBA in the soil showed that 82% of the tracer remained in the top 75 cm of the soil profile at the end of the 2009 season. This indicates that macropore flow is occurring, but has a minor influence on the movement of the salt mass. This result is important because it illustrates that although the salt mass has migrated slowly, macroporosity can transport contaminants quickly enough to exceeded drinking water quality guidelines. Breakthrough of the PFBA occurred in the north tile drain 13 hrs after application and peaked at a concentration of 10 mg/L, followed by a sharp decrease and stabilization to concentrations of 1.0 mg/L. This shows that macropore flow is occurring at depth in addition to the surface and that contaminant transport can occur rapidly in soils with lower hydraulic conductivity. Salt concentrations in the effluent were measured at high concentrations, showing that effective salt flushing of the matrix is still occurring.

  19. Shearographic Non-destructive Evaluation of Space Shuttle Thermal Protection Systems

    NASA Technical Reports Server (NTRS)

    Davis, Christopher K.; Hooker, Jeffery A.; Simmons, Stephen A.; Tenbusch, Kenneth E.

    1995-01-01

    Preliminary results of shearographic inspections of the shuttle external tank (ET) spray-on foam insulation (SOFI) and solid rocket booster (SRB) Marshall sprayable ablative (MSA-2) epoxy-cork thermal protection systems (TPS) are presented. Debonding SOFI or MSA-2 damage the orbiter 'belly' tile and exposes the ET/SRB to thermal loading. Previous work with the ET/SRB showed promising results with shearography. The first area investigated was the jack pad close-out, one of many areas on the ET where foam is applied at KSC. Voids 0.375 inch were detected in 1.75 inch thick foam using a pressure reduction of less than 0.4 psi. Of primary interest are areas of the ET that directly face the orbiter tile TPS. It is estimated that 90% of tile TPS damage on the orbiter 'belly' results from debonding SOFI during ascent. Test panels modeling these areas were manufactured with programmed debonds to determine the sensitivity of shearography as a function of debond size, SOFI thickness and vacuum. Results show repeatable detection of debonds with a diameter approximately half the SOFI thickness at less than 0.4 psi pressure reduction. Preliminary results are also presented on inspections of MSA-2 and the remote manipulator system (RMS) honeycomb material.

  20. Shearographic non-destructive evaluation of the Space Shuttle

    NASA Technical Reports Server (NTRS)

    Davis, Christopher K.; Tenbusch, Kenneth E.; Hooker, Jeffery A.; Simmons, Stephen M.

    1995-01-01

    Preliminary results of shearographic inspections of the shuttle external tank (ET) spray-on foam insulation (SOFI) and solid rocket booster (SRB) Marshall sprayable ablative (MSA-2) epoxy-cork thermal protection systems (TPS) and remote manipulator system (RMS) honeycomb are presented. Debonding SOFI or MSA-2 damage the orbiter belly tile and exposes the ET/SRB to thermal loading. Previous work with the ET/SRB showed promising results with shearography. The first area investigated was the jack pad close-out, one of many areas on the ET where foam is applied at KSC. Voids 0.375 inch were detected in 1.75 inch thick foam using a pressure reduction of less dm 0.4 psi. Of primary interest are areas of the ET that directly face the orbiter tile TPS. It is estimated that 90% of tile TPS damage on the orbiter 'belly' results from debonding SOFI during ascent. Test panels modeling these areas were manufactured with programmed debonds to determine the sensitivity of shearography as a function of debond size, SOFI thickness, and vacuum. Results show a Probability of Detection (POD) of .95 or better for of debonds with a diameter equal to the SOFI thickness at less than 0.4 psi pressure reduction. Preliminary results are also presented on inspections of MSA-2 and the remote manipulator system (RMS) honeycomb material.

  1. Shearographic non-destructive evaluation of space shuttle thermal protection systems

    NASA Technical Reports Server (NTRS)

    Hooker, Jeffrey A.; Simmons, Stephen M.; Davis, Christopher K.; Tenbusch, Kenneth E.

    1995-01-01

    Preliminary results of shearographic inspections of the shuttle external tank (ET) spray-on foam insulation (SOFI) and solid rocket booster (SRB) Marshall sprayable ablative (MSA-2) epoxy-cork thermal protection systems (TPS) are presented. Debonding SOFI or MSA-2 damage the orbiter 'belly' tile and exposes the ET/SRB to thermal loading. Previous work with the ET/SRB showed promising results with shearography. The first area investigated was the jack pad close-out, one of many areas on the ET where foam is applied at KSC. Voids 0.375 inch were detected in 1.75 inch thick foam using a pressure reduction of less than 0.4 psi. Of primary interest are areas of the ET that directly face the orbiter tile TPS. It is estimated that 90% of tile TPS damage on the orbiter 'belly' results from debonding SOFI during ascent. Test panels modeling these areas were manufactured with programmed debonds to determine the sensitivity of shearography as a function of debond size, SOFI thickness and vacuum. Results show repeatable detection of debonds with a diameter approximately half the SOFI thickness at less than 0.4 psi pressure reduction. Preliminary results are also presented on inspections of MSA-2 and the remote manipulator system (RMS) honeycomb material

  2. Hydrocarbon deposition in gaps of tungsten and graphite tiles in Experimental Advanced Superconducting Tokamak edge plasma parameters

    NASA Astrophysics Data System (ADS)

    Xu, Qian; Yang, Zhongshi; Luo, Guang-Nan

    2015-09-01

    The three-dimensional (3D) Monte Carlo code PIC-EDDY has been utilized to investigate the mechanism of hydrocarbon deposition in gaps of tungsten tiles in the Experimental Advanced Superconducting Tokamak (EAST), where the sheath potential is calculated by the 2D in space and 3D in velocity particle-in-cell method. The calculated results for graphite tiles using the same method are also presented for comparison. Calculation results show that the amount of carbon deposited in the gaps of carbon tiles is three times larger than that in the gaps of tungsten tiles when the carbon particles from re-erosion on the top surface of monoblocks are taken into account. However, the deposition amount is found to be larger in the gaps of tungsten tiles at the same CH4 flux. When chemical sputtering becomes significant as carbon coverage on tungsten increases with exposure time, the deposition inside the gaps of tungsten tiles would be considerable.

  3. Survival of Staphylococcus aureus exposed to UV radiation on the surface of ceramic tiles coated with TiO2.

    PubMed

    Szczawiński, J; Tomaszewski, H; Jackowska-Tracz, A; Szczawińska, M E

    2011-01-01

    The aim of this study was to determine and compare the antimicrobial activity of UV radiation of wavelength 253.7 nm (used in typical germicidal lamps) against Staphylococcus aureus on the surfaces of conventionally produced white ceramic wall tiles (matt and shiny) and the same tiles coated with TiO2 using three different methods: RF diode sputtering, atmospheric pressure chemical vapour deposition (APCVD) and spray pyrolysis deposition (SPD). Results clearly indicate that the bactericidal action of UV radiation is much stronger on the surfaces of tiles coated with TiO2 than on the tiles uncovered. The strongest bactericidal effect of UV radiation was found for film prepared by APCVD. Results of experiments for shiny and matt tiles did not differ statistically. The use of ceramic wall tiles coated with TiO2 films in hospitals, veterinary clinics, laboratories, food processing plants and other places where UV radiation is applied for disinfection should greatly improve the efficiency of this treatment.

  4. Analyses of microstructure, composition and retention of hydrogen isotopes in divertor tiles of JET with the ITER-like wall

    NASA Astrophysics Data System (ADS)

    Masuzaki, S.; Tokitani, M.; Otsuka, T.; Oya, Y.; Hatano, Y.; Miyamoto, M.; Sakamoto, R.; Ashikawa, N.; Sakurada, S.; Uemura, Y.; Azuma, K.; Yumizuru, K.; Oyaizu, M.; Suzuki, T.; Kurotaki, H.; Hamaguchi, D.; Isobe, K.; Asakura, N.; Widdowson, A.; Heinola, K.; Jachmich, S.; Rubel, M.; contributors, JET

    2017-12-01

    Results of the comprehensive surface analyses of divertor tiles and dusts retrieved from JET after the first ITER-like wall campaign (2011-2012) are presented. The samples cored from the divertor tiles were analyzed. Numerous nano-size bubble-like structures were observed in the deposition layer on the apron of the inner divertor tile, and a beryllium dust with the same structures were found in the matter collected from the inner divertor after the campaign. This suggests that the nano-size bubble-like structures can make the deposition layer to become brittle and may lead to cracking followed by dust generation. X-ray photoelectron spectroscopy analyses of chemical states of species in the deposition layers identified the formation of beryllium-tungsten intermetallic compounds on an inner vertical tile. Different tritium retention profiles along the divertor tiles were observed at the top surfaces and at deeper regions of the tiles by using the imaging plate technique.

  5. Finishing of display glass for mobile electronics using 3M Trizact diamond tile abrasive pads

    NASA Astrophysics Data System (ADS)

    Zheng, Lianbin; Fletcher, Tim; Na, Tee Koon; Sventek, Bruce; Romero, Vince; Lugg, Paul S.; Kim, Don

    2010-10-01

    This paper will describe a new method being used during the finishing of glass displays for mobile electronics including mobile hand held devices and notebook computers. The new method consists of using 3M TrizactTM Diamond Tile Abrasive Pads. TrizactTM Diamond Tile is a structured fixed abrasive grinding technology developed by 3M Company. The TrizactTM Diamond Tile structured abrasive pad consists of an organic (polymeric binder) - inorganic (abrasive mineral, i.e., diamond) composite that is used with a water-based coolant. TrizactTM Diamond Tile technology can be applied in both double and single side grinding applications. A unique advantage of TrizactTM Diamond Tile technology is the combination of high stock removal and low sub-surface damage. Grinding results will be presented for both 9 micron and 20 micron grades of TrizactTM Diamond Tile abrasive pads used to finish several common display glasses including Corning GorillaTM glass and Soda Lime glass.

  6. Thermal Protection System Imagery Inspection Management System -TIIMS

    NASA Technical Reports Server (NTRS)

    Goza, Sharon; Melendrez, David L.; Henningan, Marsha; LaBasse, Daniel; Smith, Daniel J.

    2011-01-01

    TIIMS is used during the inspection phases of every mission to provide quick visual feedback, detailed inspection data, and determination to the mission management team. This system consists of a visual Web page interface, an SQL database, and a graphical image generator. These combine to allow a user to ascertain quickly the status of the inspection process, and current determination of any problem zones. The TIIMS system allows inspection engineers to enter their determinations into a database and to link pertinent images and video to those database entries. The database then assigns criteria to each zone and tile, and via query, sends the information to a graphical image generation program. Using the official TIPS database tile positions and sizes, the graphical image generation program creates images of the current status of the orbiter, coloring zones, and tiles based on a predefined key code. These images are then displayed on a Web page using customized JAVA scripts to display the appropriate zone of the orbiter based on the location of the user's cursor. The close-up graphic and database entry for that particular zone can then be seen by selecting the zone. This page contains links into the database to access the images used by the inspection engineer when they make the determination entered into the database. Status for the inspection zones changes as determinations are refined and shown by the appropriate color code.

  7. How to describe disordered structures

    PubMed Central

    Nishio, Kengo; Miyazaki, Takehide

    2016-01-01

    Disordered structures such as liquids and glasses, grains and foams, galaxies, etc. are often represented as polyhedral tilings. Characterizing the associated polyhedral tiling is a promising strategy to understand the disordered structure. However, since a variety of polyhedra are arranged in complex ways, it is challenging to describe what polyhedra are tiled in what way. Here, to solve this problem, we create the theory of how the polyhedra are tiled. We first formulate an algorithm to convert a polyhedron into a codeword that instructs how to construct the polyhedron from its building-block polygons. By generalizing the method to polyhedral tilings, we describe the arrangements of polyhedra. Our theory allows us to characterize polyhedral tilings, and thereby paves the way to study from short- to long-range order of disordered structures in a systematic way. PMID:27064833

  8. How to describe disordered structures

    NASA Astrophysics Data System (ADS)

    Nishio, Kengo; Miyazaki, Takehide

    2016-04-01

    Disordered structures such as liquids and glasses, grains and foams, galaxies, etc. are often represented as polyhedral tilings. Characterizing the associated polyhedral tiling is a promising strategy to understand the disordered structure. However, since a variety of polyhedra are arranged in complex ways, it is challenging to describe what polyhedra are tiled in what way. Here, to solve this problem, we create the theory of how the polyhedra are tiled. We first formulate an algorithm to convert a polyhedron into a codeword that instructs how to construct the polyhedron from its building-block polygons. By generalizing the method to polyhedral tilings, we describe the arrangements of polyhedra. Our theory allows us to characterize polyhedral tilings, and thereby paves the way to study from short- to long-range order of disordered structures in a systematic way.

  9. Jagged Tiling for Intra-tile Parallelism and Fine-Grain Multithreading

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shrestha, Sunil; Manzano Franco, Joseph B.; Marquez, Andres

    In this paper, we have developed a novel methodology that takes into consideration multithreaded many-core designs to better utilize memory/processing resources and improve memory residence on tileable applications. It takes advantage of polyhedral analysis and transformation in the form of PLUTO, combined with a highly optimized finegrain tile runtime to exploit parallelism at all levels. The main contributions of this paper include the introduction of multi-hierarchical tiling techniques that increases intra tile parallelism; and a data-flow inspired runtime library that allows the expression of parallel tiles with an efficient synchronization registry. Our current implementation shows performance improvements on an Intelmore » Xeon Phi board up to 32.25% against instances produced by state-of-the-art compiler frameworks for selected stencil applications.« less

  10. Combination of geochemical and hydrobiological tracers for the analysis of runoff generating processes in a lowland catchment

    NASA Astrophysics Data System (ADS)

    Faber, Claas; Wu, Naicheng; Ulrich, Uta; Fohrer, Nicola

    2015-04-01

    Since lowlands are characterised by flat topography and low hydraulic gradients, groundwater inflow has a large influence to streamflow generation in such catchments. In catchments with intense agricultural land use, artificial drainages are often another major contributor to streamflow. They shorten the soil passage and thus change the matter retention potential as well as runoff dynamics of a catchment. Contribution of surface runoff to streamflow is usually less important in volume. However, due to high concentrations of agrochemicals, surface runoff can constitute an important entry pathway into water bodies, especially if strong precipitation events coincide with fertilizer or pesticide application. The DFG funded project "Separating surface runoff from tile drainage flow in agricultural lowland catchments based on diatoms to improve modelled runoff components and phosphorous transport" investigates prevalent processes in this context in a 50 km² lowland catchment (Kielstau, Schleswig-Holstein, Germany) with the goal of improving existing models. End Member Mixing Analysis (EMMA) is used in the project to determine the relative importance of groundwater, tile drainage and surface runoff to streamflow at daily time steps. It became apparent that geochemical tracers are suitable for distinguishing surface runoff, but are weak for the separation of tile drainage and groundwater influence. We attribute this to the strong and complex interaction between soil water and shallow groundwater tables in the catchment. Recent studies (e.g. Pfister et al. 2011, Tauro et al. 2013) show the potential of diatoms as indicators for hydrological processes. Since we found diatoms to be suitable for the separation of tile drainage and stream samples (Wu et al., unpublished data) in our catchment, we are able to include diatom derived indices (e.g. density, species moisture indices, diversity indices) as traces in EMMA. Our results show that the inclusion of diatom data in the EMMA dataset improves the ability to distinguish tile drainage, groundwater and surface runoff influence to streamflow in our agriculturally dominated lowland catchment. Keywords: tile drainage, surface runoff, groundwater, hydrograph separation, EMMA, dia-toms, water quality, lowland catchments References: Pfister L, Wetzel CE, Martínez-Carreras N, Frentress J, Ector L, Hoffmann L, McDonnell JJ. 2011. Do diatoms run downhill? Using biodiversity of terrestrial and aquatic diatoms to identify hydrological connectivity between aquatic zones in Luxembourg. AGU Fall Meeting. Tauro F, Martínez-Carreras N, Wetzel CE, Hissler C, Barnich F, Frentress J, Ector L, Hoff-mann L, McDonnell JJ, Pfister L. 2013. Fluorescent diatoms as hydrological tracers: a proof of concept percolation experiment. EGU abstract, EGU2013-7687-4.

  11. Impact of data layouts on the efficiency of GPU-accelerated IDW interpolation.

    PubMed

    Mei, Gang; Tian, Hong

    2016-01-01

    This paper focuses on evaluating the impact of different data layouts on the computational efficiency of GPU-accelerated Inverse Distance Weighting (IDW) interpolation algorithm. First we redesign and improve our previous GPU implementation that was performed by exploiting the feature of CUDA dynamic parallelism (CDP). Then we implement three versions of GPU implementations, i.e., the naive version, the tiled version, and the improved CDP version, based upon five data layouts, including the Structure of Arrays (SoA), the Array of Structures (AoS), the Array of aligned Structures (AoaS), the Structure of Arrays of aligned Structures (SoAoS), and the Hybrid layout. We also carry out several groups of experimental tests to evaluate the impact. Experimental results show that: the layouts AoS and AoaS achieve better performance than the layout SoA for both the naive version and tiled version, while the layout SoA is the best choice for the improved CDP version. We also observe that: for the two combined data layouts (the SoAoS and the Hybrid), there are no notable performance gains when compared to other three basic layouts. We recommend that: in practical applications, the layout AoaS is the best choice since the tiled version is the fastest one among three versions. The source code of all implementations are publicly available.

  12. Development of New Generation of Perspireable Skin

    DTIC Science & Technology

    2015-02-20

    Coefficient of Thermal Expansion (CTE) material simulating Reinforced Carbon - Carbon Composites (RCC). These tiles made of different materials...Very low thermal expansion coefficient materials, Annu. Rev. Mater. Sci., 1989, 19, 59-81 3. Mittal, R. and Chaplot S.L., Lattice dynamical...thermal expansion from0.3 to 1050 Kelvin in ZrW2O8, Science, 1996, 272, 90-92 6. G. Savage, Carbon - carbon composites, New York: Chapman & Hall, pp

  13. Modelling rapid flow response of a tile drained hillslope with explicit representation of preferential flow paths and consideration of equifinal model structures

    NASA Astrophysics Data System (ADS)

    Klaus, Julian; Zehe, Erwin

    2010-05-01

    Rapid water flow along spatially connected - often biologically mediated - flow paths of minimum flow resistance is widely acknowledged to play a key role in runoff generation at the hillslope and small catchment scales but also in the transport of solutes like agro chemicals and nutrients in cohesive soils. Especially at tile drained fields site connected vertical flow structures such as worm burrows, roots or shrinkage cracks act as short cuts allowing water flow to bypass the soil matrix. In the present study we propose a spatially explicit approach to represent worm burrows as connected structures of high conductivity and low retention capacity in a 2D physically model. With this approach tile drain discharge and preferential flow patterns in soil observed during the irrigation of a tile drained hillslope in the Weiherbach catchment were modelled. The model parameters derived from measurements and are considered to be uncertain. Given this uncertainty of key factors that organise flow and transport at tile drained sites the main objectives of the present studies are to shed light on the following three questions: 1. Does a simplified approach that explicitly represents worm burrows as continuous flow paths of small flow resistance and low retention properties in a 2D physically model allow successful reproduction of event flow response at a tile drained field site in the Weiherbach catchment? 2. Does the above described uncertainty in key factors cause equifinality i.e. are there several model structural setups that reproduce event flow response in an acceptable manner without compromising our physical understanding of the system? 3. If so, what are the key factors that have to be known at high accuracy to reduce the equifinality of model structures? The issue of equifinality is usually discussed in catchment modelling to indicate that often a large set of conceptual model parameter sets allows acceptable reproduction of the behaviour of the system of interest - in many cases catchment stream flow response. Beven and Binley (1992) suggest that these model structures should be considered to be equally likely to account for predictive uncertainty. In this study we show that the above outline approach allows successful prediction of the tile drain discharge and preferential flow patterns in soil observed during the irrigation of a tile drained hillslope in the Weiherbach catchment flow event. Strikingly we a found a considerable equifinality in the model structural setup, when key parameters such as the area density of worm burrows, their hydraulic conductivity and the conductivity of the tile drains were varied within the ranges of either our measurements or measurements reported in the literature. Thirteen different model setups yielded a normalised time-shifted Nash-Sutcliffe of more than 0.9, which means that more than 90% of the flow variability is explained by the model. Also the flow volumes were in good accordance and timing errors were less or equal than 20 min (which corresponds to two simulation output time steps). It is elaborated that this uncertainty/equifinality could be reduced when more precise data on initial states of the subsurface and on the drainage area of a single drainage tube could be made available. However, such data are currently most difficult to assess even at very well investigated site as the one that is dealt with here. We thus suggest non uniqueness of process based model structures seems thus to be an important factor causing predictive uncertainty at many sites where preferential flow dominates systems response. References Beven, K.J. and Binley, A.M., 1992. The future of distributed models: model calibration and uncertainty prediction, Hydrological Processes, 6, p.279-298.

  14. SAFER Inspection of Space Shuttle Thermal Protection System

    NASA Technical Reports Server (NTRS)

    Scoville, Zebulon C.; Rajula, Sudhakar

    2005-01-01

    In the aftermath of the space shuttle Columbia accident, it quickly became clear that new methods would need to be developed that would provide the capability to inspect and repair the shuttle's thermal protection system (TPS). A boom extension to the Remote Manipulator System (RMS) with a laser topography sensor package was identified as the primary means for measuring the damage depth in acreage tile as well as scanning Reinforced Carbon- Carbon (RCC) surfaces. However, concern over the system's fault tolerance made it prudent to investigate alternate means of acquiring close range photographs and contour depth measurements in the event of a failure. One method that was identified early was to use the Simplified Aid For EVA Rescue (SAFER) propulsion system to allow EVA access to damaged areas of concern. Several issues were identified as potential hazards to SAFER use for this operation. First, the ability of an astronaut to maintain controlled flight depends upon efficient technique and hardware reliability. If either of these is insufficient during flight operations, a safety tether must be used to rescue the crewmember. This operation can jeopardize the integrity of the Extra-vehicular Mobility Unit (EMU) or delicate TPS materials. Controls were developed to prevent the likelihood of requiring a tether rescue, and procedures were written to maximize the chances for success if it cannot be avoided. Crewmember ability to manage tether cable tension during nominal flight also had to be evaluated to ensure it would not negatively affect propellant consumption. Second, although propellant consumption, flight control, orbital dynamics, and flight complexity can all be accurately evaluated in Virtual Reality (VR) Laboratory at Johnson Space Center, there are some shortcomings. As a crewmember's hand is extended to simulate measurement of tile damage, it will pass through the vehicle without resistance. In reality, this force will push the crewmember away from the vehicle, and could induce a moment which, if strong enough, could saturate the attitude control system in SAFER. This raises the concern that additional propellant will be consumed to maintain controlled flight. To account for this, the fidelity of the Virtual Reality simulation was improved to include the effect of crewmember contact with the vehicle during SAFER flight. In addition, while participating in VR simulations, the subject is in shirt sleeves and sits in a chair. This does not provide a flight-like representation of body position awareness. To prevent inadvertent contact with tile or RCC, other facilities were utilized to establish crew preferences for body attitude and tool configuration. Finally, a study was performed to determine if attitude constraints are needed for the Space shuttle and International Space Station to reduce SAFER flight difficulty.

  15. Tiling a figure using a height in a tree

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Remila, E.

    1996-12-31

    We first give a new presentation of an algorithm from Thurston of tiling with lozenges formed from two cells of the triangular lattice A. Secondly we extend the method to get a linear algorithm of tiling with leaning dominoes (parallelograms formed from four cells of {Lambda}) and triangles (formed from four cells of {Lambda}). Thirdly, we produce a quadratic algorithm of tiling with leaning dominoes.

  16. Priority coding for control room alarms

    DOEpatents

    Scarola, Kenneth; Jamison, David S.; Manazir, Richard M.; Rescorl, Robert L.; Harmon, Daryl L.

    1994-01-01

    Indicating the priority of a spatially fixed, activated alarm tile on an alarm tile array by a shape coding at the tile, and preferably using the same shape coding wherever the same alarm condition is indicated elsewhere in the control room. The status of an alarm tile can change automatically or by operator acknowledgement, but tones and/or flashing cues continue to provide status information to the operator.

  17. Seamless stitching of tile scan microscope images.

    PubMed

    Legesse, F B; Chernavskaia, O; Heuke, S; Bocklitz, T; Meyer, T; Popp, J; Heintzmann, R

    2015-06-01

    For diagnostic purposes, optical imaging techniques need to obtain high-resolution images of extended biological specimens in reasonable time. The field of view of an objective lens, however, is often smaller than the sample size. To image the whole sample, laser scanning microscopes acquire tile scans that are stitched into larger mosaics. The appearance of such image mosaics is affected by visible edge artefacts that arise from various optical aberrations which manifest in grey level jumps across tile boundaries. In this contribution, a technique for stitching tiles into a seamless mosaic is presented. The stitching algorithm operates by equilibrating neighbouring edges and forcing the brightness at corners to a common value. The corrected image mosaics appear to be free from stitching artefacts and are, therefore, suited for further image analysis procedures. The contribution presents a novel method to seamlessly stitch tiles captured by a laser scanning microscope into a large mosaic. The motivation for the work is the failure of currently existing methods for stitching nonlinear, multimodal images captured by our microscopic setups. Our method eliminates the visible edge artefacts that appear between neighbouring tiles by taking into account the overall illumination differences among tiles in such mosaics. The algorithm first corrects the nonuniform brightness that exists within each of the tiles. It then compensates for grey level differences across tile boundaries by equilibrating neighbouring edges and forcing the brightness at the corners to a common value. After these artefacts have been removed further image analysis procedures can be applied on the microscopic images. Even though the solution presented here is tailored for the aforementioned specific case, it could be easily adapted to other contexts where image tiles are assembled into mosaics such as in astronomical or satellite photos. © 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.

  18. Progress in HTS trapped field magnets: J(sub c), area, and applications

    NASA Technical Reports Server (NTRS)

    Weinstein, Roy; Ren, Yanru; Liu, Jianxiong; Sawh, Ravi; Parks, Drew; Foster, Charles; Obot, Victor; Arndt, G. Dickey; Crapo, Alan

    1995-01-01

    Progress in trapped field magnets is reported. Single YBCO grains with diameters of 2 cm are made in production quantities, while 3 cm, 4 1/2 cm and 6 cm diameters are being explored. For single grain tiles: J(sub c) is approximately 10,000 A/cm(exp 2) for melt textured grains; J(sub c) is approximately 40,000 A/cm2 for light ion irradiation; and J(sub c) is approximately 85,000 A/cm(exp 2) for heavy ion irradiation. Using 2 cm diameter tiles bombarded by light ions, we have fabricated a mini-magnet which trapped 2.25 Tesla at 77K, and 5.3 Tesla at 65K. A previous generation of tiles, 1 cm x 1 cm, was used to trap 7.0 Tesla at 55K. Unirradiated 2.0 cm tiles were used to provide 8 magnets for an axial gap generator, in a collaborative experiment with Emerson Electric Co. This generator delivered 100 Watts to a resistive load, at 2265 rpm. In this experiment activation of the TFMs was accomplished by a current pulse of 15 ms duration. Tiles have also been studied for application as a bumper-tether system for the soft docking of spacecraft. A method for optimizing tether forces, and mechanisms of energy dissipation are discussed. A bus bar was constructed by welding three crystals while melt-texturing, such that their a,b planes were parallel and interleaved. The bus bar, an area of approximately 2 cm(exp 2), carried a transport current of 1000 amps, the limit of the testing equipment available.

  19. Progress in HTS Trapped Field Magnets: J(sub c), Area, and Applications

    NASA Technical Reports Server (NTRS)

    Weinstein, Roy; Ren, Yanru; Liu, Jian-Xiong; Sawh, Ravi; Parks, Drew; Foster, Charles; Obot, Victor; Arndt, G. Dickey; Crapo, Alan

    1995-01-01

    Progress in trapped field magnets is reported. Single YBCO grains with diameters of 2 cm are made in production quantities, while 3 cm, 4 1/2 cm and 6 cm diameters are being explored. For single grain tiles: J(sub c) - 10,000 A/sq cm for melt textured grains; J(sub c) - 40,000 A/sq cm for light ion irradiation; and J(sub c) - 85,000 A/J(sub c) for heavy ion irradiation. Using 2 cm diameter tiles bombarded by light ions, we have fabricated a mini-magnet which trapped 2.25 Tesla at 77K, and 5.3 Tesla at 65K. A previous generation of tiles, 1 cm x 1 cm, was used to trap 7.0 Tesla at 55K. Unirradiated 2.0 cm tiles were used to provide 8 magnets for an axial gap generator, in a collaborative experiment with Emerson Electric Co. This generator delivered 100 Watts to a resistive load, at 2265 rpm. In this experiment, activation of the TFMs was accomplished by a current pulse of 15 ms duration. Tiles have also been studied for application as a bumper-tether system for the soft docking of spacecraft. A method for optimizing tether forces, and mechanisms of energy dissipation are discussed. A bus bar was constructed by welding three crystals while melt-texturing, such that their a,b planes were parallel and interleaved. The bus bar, of area approx. 2 sq cm, carried a transport current of 1000 amps, the limit of the testing equipment available.

  20. Supporting Tablet Configuration, Tracking, and Infection Control Practices in Digital Health Interventions: Study Protocol

    PubMed Central

    Furberg, Robert D; Zulkiewicz, Brittany A; Hudson, Jordan P; Taylor, Olivia M; Lewis, Megan A

    2016-01-01

    Background Tablet-based health care interventions have the potential to encourage patient care in a timelier manner, allow physicians convenient access to patient records, and provide an improved method for patient education. However, along with the continued adoption of tablet technologies, there is a concomitant need to develop protocols focusing on the configuration, management, and maintenance of these devices within the health care setting to support the conduct of clinical research. Objective Develop three protocols to support tablet configuration, tablet management, and tablet maintenance. Methods The Configurator software, Tile technology, and current infection control recommendations were employed to develop three distinct protocols for tablet-based digital health interventions. Configurator is a mobile device management software specifically for iPhone operating system (iOS) devices. The capabilities and current applications of Configurator were reviewed and used to develop the protocol to support device configuration. Tile is a tracking tag associated with a free mobile app available for iOS and Android devices. The features associated with Tile were evaluated and used to develop the Tile protocol to support tablet management. Furthermore, current recommendations on preventing health care–related infections were reviewed to develop the infection control protocol to support tablet maintenance. Results This article provides three protocols: the Configurator protocol, the Tile protocol, and the infection control protocol. Conclusions These protocols can help to ensure consistent implementation of tablet-based interventions, enhance fidelity when employing tablets for research purposes, and serve as a guide for tablet deployments within clinical settings. PMID:27350013

  1. Directed nucleation assembly of DNA tile complexes for barcode-patterned lattices

    PubMed Central

    Yan, Hao; LaBean, Thomas H.; Feng, Liping; Reif, John H.

    2003-01-01

    The programmed self-assembly of patterned aperiodic molecular structures is a major challenge in nanotechnology and has numerous potential applications for nanofabrication of complex structures and useful devices. Here we report the construction of an aperiodic patterned DNA lattice (barcode lattice) by a self-assembly process of directed nucleation of DNA tiles around a scaffold DNA strand. The input DNA scaffold strand, constructed by ligation of shorter synthetic oligonucleotides, provides layers of the DNA lattice with barcode patterning information represented by the presence or absence of DNA hairpin loops protruding out of the lattice plane. Self-assembly of multiple DNA tiles around the scaffold strand was shown to result in a patterned lattice containing barcode information of 01101. We have also demonstrated the reprogramming of the system to another patterning. An inverted barcode pattern of 10010 was achieved by modifying the scaffold strands and one of the strands composing each tile. A ribbon lattice, consisting of repetitions of the barcode pattern with expected periodicity, was also constructed by the addition of sticky ends. The patterning of both classes of lattices was clearly observable via atomic force microscopy. These results represent a step toward implementation of a visual readout system capable of converting information encoded on a 1D DNA strand into a 2D form readable by advanced microscopic techniques. A functioning visual output method would not only increase the readout speed of DNA-based computers, but may also find use in other sequence identification techniques such as mutation or allele mapping. PMID:12821776

  2. Investigating summer flow paths in a Dutch agricultural field using high frequency direct measurements

    NASA Astrophysics Data System (ADS)

    Delsman, J. R.; Waterloo, M. J.; Groen, M. M. A.; Groen, J.; Stuyfzand, P. J.

    2014-11-01

    The search for management strategies to cope with projected water scarcity and water quality deterioration calls for a better understanding of the complex interaction between groundwater and surface water in agricultural catchments. We separately measured flow routes to tile drains and an agricultural ditch in a deep polder in the coastal region of the Netherlands, characterized by exfiltration of brackish regional groundwater flow and intake of diverted river water for irrigation and water quality improvement purposes. We simultaneously measured discharge, electrical conductivity and temperature of these separate flow routes at hourly frequencies, disclosing the complex and time-varying patterns and origins of tile drain and ditch exfiltration. Tile drainage could be characterized as a shallow flow system, showing a non-linear response to groundwater level changes. Tile drainage was fed primarily by meteoric water, but still transported the majority (80%) of groundwater-derived salt to surface water. In contrast, deep brackish groundwater exfiltrating directly in the ditch responded linearly to groundwater level variations and is part of a regional groundwater flow system. We could explain the observed salinity of exfiltrating drain and ditch water from the interaction between the fast-responding pressure distribution in the subsurface that determined groundwater flow paths (wave celerity), and the slow-responding groundwater salinity distribution (water velocity). We found water demand for maintaining water levels and diluting salinity through flushing to greatly exceed the actual sprinkling demand. Counterintuitively, flushing demand was found to be largest during precipitation events, suggesting the possibility of water savings by operational flushing control.

  3. Development of anti-slip sustainable tiles from agricultural waste

    NASA Astrophysics Data System (ADS)

    Zulkefli, Zainordin Firdaus; Zainol, Mohd Remy Rozainy Mohd Arif; Osman, Norhayati

    2017-04-01

    In general of 80% the human activities is located in the building. Buildings constructed should be in line with full functions and optimum safety features. Aspects to be emphasized is the slip on the floor of the building. The selection of tiles must have anti-slip characteristics and achieve standard strength stress. This study is conducted to develop anti-slip tiles modification using agricultural waste. The material used is agricultural waste such rice husks, palm fibre and saw dusk mixed into the clay and then baked at a temperature of 900-1185 C °. Agricultural waste mixture ratio is 5%, 10% and 15%. The samples of tiles are produced for experiments. The results of agricultural waste tiles show that the strength is higher than standard strength, the water absorption less than standard tiles and pendulum value test is exceeds 36.

  4. Automated 3D Damaged Cavity Model Builder for Lower Surface Acreage Tile on Orbiter

    NASA Technical Reports Server (NTRS)

    Belknap, Shannon; Zhang, Michael

    2013-01-01

    The 3D Automated Thermal Tool for Damaged Acreage Tile Math Model builder was developed to perform quickly and accurately 3D thermal analyses on damaged lower surface acreage tiles and structures beneath the damaged locations on a Space Shuttle Orbiter. The 3D model builder created both TRASYS geometric math models (GMMs) and SINDA thermal math models (TMMs) to simulate an idealized damaged cavity in the damaged tile(s). The GMMs are processed in TRASYS to generate radiation conductors between the surfaces in the cavity. The radiation conductors are inserted into the TMMs, which are processed in SINDA to generate temperature histories for all of the nodes on each layer of the TMM. The invention allows a thermal analyst to create quickly and accurately a 3D model of a damaged lower surface tile on the orbiter. The 3D model builder can generate a GMM and the correspond ing TMM in one or two minutes, with the damaged cavity included in the tile material. A separate program creates a configuration file, which would take a couple of minutes to edit. This configuration file is read by the model builder program to determine the location of the damage, the correct tile type, tile thickness, structure thickness, and SIP thickness of the damage, so that the model builder program can build an accurate model at the specified location. Once the models are built, they are processed by the TRASYS and SINDA.

  5. The Geoscience Laser Altimeter System Laser Transmitter

    NASA Technical Reports Server (NTRS)

    Afzal, R. S.; Dallas, J. L.; Yu, A. W.; Mamakos, W. A.; Lukemire, A.; Schroeder, B.; Malak, A.

    2000-01-01

    The Geoscience Laser Altimeter System (GLAS), scheduled to launch in 2001, is a laser altimeter and lidar for tile Earth Observing System's (EOS) ICESat mission. The laser transmitter requirements, design and qualification test results for this space- based remote sensing instrument are presented.

  6. Orbiter Boom Sensor System extended

    NASA Image and Video Library

    2005-07-27

    STS114-E-5330 (28 July 2005) --- As seen from Discovery's cabin, STS-114 Remote Manipulator System (RMS) robot arm flexes above Earth. Crews of Space Station and Discovery will later use RMS and boom to study Shuttle's tiles.

  7. Machine Intelligence

    DTIC Science & Technology

    2013-03-01

    Although this approach is an improvement over fixed tile coding methods like CMAC, it suffers from a significant drawback . This approach splits the tiles in...serious drawbacks to using them effectively. Engineering a tiling is typically done by hand, and it can be very difficult to find an appropriate tiling...however, there are still some drawbacks that need to be addressed. While the boundaries are redrawn according to the chance of a mutation to the neural

  8. 75 FR 28316 - Notice of Buy America Waiver Request by Oregon Department of Transportation for Steel Roof Tiles...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-20

    ... by Oregon Department of Transportation for Steel Roof Tiles To Be Used in Union Station Roof... (``PRIIA'') (49 U.S.C. 24405(a)) for the purchase of metal roof tiles made of 40/45 KSI 2, 24 Gauge (0.0276... Register. This notice informs the public that ODOT has requested a Buy America waiver for the roofing tiles...

  9. Effects of waste glass and waste foundry sand additions on reclaimed tiles containing sewage sludge ash.

    PubMed

    Lin, Deng-Fong; Luo, Huan-Lin; Lin, Kuo-Liang; Liu, Zhe-Kun

    2017-07-01

    Applying sewage sludge ash (SSA) to produce reclaimed tiles is a promising recycling technology in resolving the increasing sludge wastes from wastewater treatment. However, performance of such reclaimed tiles is inferior to that of original ceramic tiles. Many researchers have therefore tried adding various industrial by-products to improve reclaimed tile properties. In this study, multiple materials including waste glass and waste foundry sand (WFS) were added in an attempt to improve physical and mechanical properties of reclaimed tiles with SSA. Samples with various combinations of clay, WFS, waste glass and SSA were made with three kiln temperatures of 1000°C, 1050°C, and 1100°C. A series of tests on the samples were next conducted. Test results showed that waste glass had positive effects on bending strength, water absorption and weight loss on ignition, while WFS contributed the most in reducing shrinkage, but could decrease the tile bending strength when large amount was added at a high kiln temperature. This study suggested that a combination of WFS from 10% to 15%, waste glass from 15% to 20%, SSA at 10% at a kiln temperature between 1000°C and 1050°C could result in quality reclaimed tiles with a balanced performance.

  10. Acid-Alkali Resistance of New Reclaimed Tiles Containing Sewage Sludge Ash and Waste Glass

    PubMed Central

    Lin, Deng-Fong; Lin, Kuo-Liang; Luo, Huan-Lin; Xu, Jia-Qin

    2016-01-01

    In this study, properties of newly developed reclaimed tiles in a harmful environment were investigated. A portion of clay used to manufacture tiles was replaced with sewage sludge ash (SSA) and waste glass to produce the new reclaimed tiles. To investigate the effects of SSA and waste glass on the properties of the tiles, different specimens were blended and placed in acid-alkali solutions. The reclaimed tile specimens were manufactured by clay, 10% SSA, and five different mixes of waste glass replacement, namely, 0%, 10%, 20%, 40%, and 60%. These specimens were calcined at 1000 °C and subsequently underwent a series of tests, including TGA/DTA (thermogravimetric analysis/differential thermal analysis), SEM (scanning electron microscopy), XRD (X-ray diffraction), bending strength, weight loss, and porosity. Test results show that shortcomings associated with the introduction of the sludge ash were improved by the admixture of waste glass, especially in the aspects of shrinkage and bending strength. The study showed that the new reclaimed tiles performed relatively well in acid-alkali resistance tests but appeared to have better alkali resistance than acid resistance. It was also found that the optimal mix of such reclaimed tiles was 10% SSA, 10% waste glass, and 80% clay. PMID:28773668

  11. Nondeterministic self-assembly of two tile types on a lattice.

    PubMed

    Tesoro, S; Ahnert, S E

    2016-04-01

    Self-assembly is ubiquitous in nature, particularly in biology, where it underlies the formation of protein quaternary structure and protein aggregation. Quaternary structure assembles deterministically and performs a wide range of important functions in the cell, whereas protein aggregation is the hallmark of a number of diseases and represents a nondeterministic self-assembly process. Here we build on previous work on a lattice model of deterministic self-assembly to investigate nondeterministic self-assembly of single lattice tiles and mixtures of two tiles at varying relative concentrations. Despite limiting the simplicity of the model to two interface types, which results in 13 topologically distinct single tiles and 106 topologically distinct sets of two tiles, we observe a wide variety of concentration-dependent behaviors. Several two-tile sets display critical behaviors in the form of a sharp transition from bound to unbound structures as the relative concentration of one tile to another increases. Other sets exhibit gradual monotonic changes in structural density, or nonmonotonic changes, while again others show no concentration dependence at all. We catalog this extensive range of behaviors and present a model that provides a reasonably good estimate of the critical concentrations for a subset of the critical transitions. In addition, we show that the structures resulting from these tile sets are fractal, with one of two different fractal dimensions.

  12. Effects of occupational exposures and smoking on lung function in tile factory workers.

    PubMed

    Jaakkola, Maritta S; Sripaiboonkij, Penpatra; Jaakkola, Jouni J K

    2011-02-01

    The aims of this study were to investigate the relations of occupational exposures in tile industry to lung function and to evaluate potential interaction between smoking and tile dust exposure containing silica. A cross-sectional study of 232 workers (response rate 100%) in a tile factory and 76 office workers (response rate 73%) from four factories in Thailand was conducted in 2006-2007. Participants answered a questionnaire and performed spirometry. Factory workers had lower spirometric functions than office workers, especially those with high dust exposure. There was a dose-response relation between duration of dust exposure and FEV1 and FVC, the adjusted effect of ≥ 21 years of exposure on FEV1 being -240 ml (-100 to -380) and on FVC -300 ml (-140 to -460). The adverse effect of dust on lung function was larger in current smokers suggesting synergism between smoking and tile dust exposure. This study provides evidence that long-term exposure to dust in tile industry is related to lung function reduction. There was a suggestion of synergistic effect between dust exposure and smoking. Tile factories should consider measures to reduce dust exposure and arrange spirometry surveillance for workers with such exposure. Smoking cessation should be promoted to prevent harmful effects of occupational tile dust exposure.

  13. Return to Flight: Crew Activities Resource Reel 1 of 2

    NASA Technical Reports Server (NTRS)

    2005-01-01

    The crew of the STS-114 Discovery Mission is seen in various aspects of training for space flight. The crew activities include: 1) STS-114 Return to Flight Crew Photo Session; 2) Tile Repair Training on Precision Air Bearing Floor; 3) SAFER Tile Inspection Training in Virtual Reality Laboratory; 4) Guidance and Navigation Simulator Tile Survey Training; 5) Crew Inspects Orbital Boom and Sensor System (OBSS); 6) Bailout Training-Crew Compartment; 7) Emergency Egress Training-Crew Compartment Trainer (CCT); 8) Water Survival Training-Neutral Buoyancy Lab (NBL); 9) Ascent Training-Shuttle Motion Simulator; 10) External Tank Photo Training-Full Fuselage Trainer; 11) Rendezvous and Docking Training-Shuttle Engineering Simulator (SES) Dome; 12) Shuttle Robot Arm Training-SES Dome; 13) EVA Training Virtual Reality Lab; 14) EVA Training Neutral Buoyancy Lab; 15) EVA-2 Training-NBL; 16) EVA Tool Training-Partial Gravity Simulator; 17) Cure in Place Ablator Applicator (CIPAA) Training Glove Vacuum Chamber; 16) Crew Visit to Merritt Island Launch Area (MILA); 17) Crew Inspection-Space Shuttle Discovery; and 18) Crew Inspection-External Tank and Orbital Boom and Sensor System (OBSS). The crew are then seen answering questions from the media at the Space Shuttle Landing Facility.

  14. SiPM photosensors and fast timing readout for the Barrel Time-of-Flight detector in bar PANDA

    NASA Astrophysics Data System (ADS)

    Suzuki, K.

    2018-03-01

    The Barrel Time-of-Flight detector system will be installed in the upcoming bar PANDA experiment at FAIR in Germany. The detector has a barrel shape of phi=0.5 m and 1.8 m long, covering about 5 m2, which corresponds to the laboratory polar angle coverage of 22o<θ<140o. The detector is a scintillation tile hodoscope. A single scintillation tile segment has a dimension of 90× 30 mm2 and 5 mm thickness, and photons are detected by Silicon Photomultipliers at both ends. 4 Silicon Photomultipliers are combined to work as a single sensor in order to increase the sensitive area and to improve the timing performance. In total, the system consists of 1920 scintillator tiles, 3840 readout channels, and makes use of 15360 Silicon Photomultiplier sensors. In this paper, the requirement, design and the result of an actual performance test of the bar PANDA Barrel Time-of-Flight detector are presented. The test shows that the current design fulfils satisfactorily the required timing performance (σt~ 56 ps) and the timing performance depends little on the hit position on the surface.

  15. Diagnostic and Hardware Upgrades for the US-PRC PMI Collaboration on EAST

    NASA Astrophysics Data System (ADS)

    Tritz, Kevin; Maingi, R.; Andruczyk, D.; Canik, J.; Wang, Z.; Wirth, B.; Zinkle, S.; Woller, K.; Hu, J. S.; Luo, G. N.; Gong, X. Z.; EAST Team

    2017-10-01

    Several collaborative diagnostic and hardware upgrades are planned to improve understanding and control of Plasma-Material Interactions on EAST, as part of the US-PRC PMI collaboration. Dual-band thermography adapters, designed by UT-K and ORNL, are being designed for existing IR cameras to improve the accuracy of the divertor heat flux measurements by reducing sensitivity to surface emissivity. These measurements should improve power accounting for EAST discharges, which can show a large gap between input power and divertor exhaust power. MIT is preparing tungsten tiles with fluorine depth markers to measure net erosion of PFC tiles. JHU plans to improve the electronics of the Multi-Energy Soft X-ray diagnostic as well as expand the present edge system to a full core-edge measurement; this will enhance the assessment of the effect of Li injection on tungsten accumulation and transport. In addition to PPPL-developed upgrades to the lithium granule and pellet delivery systems, LANL is assessing core-shell micropellets for pellet ablation analysis. Finally, UIUC and PPPL are developing flowing liquid lithium limiters, both with and without LiMIT tile features, for deployment on EAST. Work supported by DoE award DE-SC0016553.

  16. Electric Currents Generated by Gabbro during Dynamic Uniaxial Loading

    NASA Astrophysics Data System (ADS)

    Jones, H. H.; Lau, B. W.; Takeuchi, A. T.; Freund, F. T.

    2006-12-01

    Igneous rocks, when subjected to deviatory stress, turn into a battery. Dynamically stressed rocks can generate large currents. We report on gabbro (Shanxi, China). We use steel pistons to load ~10 cm3 in the center of 30 x 30 x 0.9 cm3 tiles, from 0 to 60 MPa, 1/3 failure strength. Instantly upon loading, a current begins to flow, increasing rapidly to 200-300 pA. One part of the current is carried by electrons, which flow from the stressed rock into the steel pistons and through the external circuit to the edges of the tile. The other part is carried by holes, which flow inside the rock, from the stressed to the unstressed rock and the edges of the tile. At the edges the two charge carriers meet, thereby closing the circuit. Changing the stress rates from 0.0002 to 100 MPa/sec causes the steady currents to increase from ~30,000 A/km3 to ~50,000 A/km3 and an initial spike to develop reaching 300,000 A/km3 at the highest stress rate. Both, electrons and holes, are associated with oxygen anions that changed their valence from 2- to 1- (peroxy). An O- among O2- represents a defect electron in the O2- sublattice, known as positive hole or p-hole for short. In unstressed rocks the O- exist in an electrically inactive form as O- pairs, chemically equivalent to peroxy links, O3X-OO-XO3 with X = Si4+, Al3+ etc. Stresses cause the peroxy links to break, allowing electrons from neighboring O2- to jump in and p-holes to jump out. The p-holes can spread through unstressed rocks using energy levels in the valence band. Sustained large battery currents can flow, for instance in the aftermath of an impact, when the holes can close the circuit by linking up with the electrons. If the circuit is not closed, no battery currents flow.

  17. Aerodynamic pressure and heating-rate distributions in tile gaps around chine regions with pressure gradients at a Mach number of 6.6

    NASA Technical Reports Server (NTRS)

    Hunt, L. Roane; Notestine, Kristopher K.

    1990-01-01

    Surface and gap pressures and heating-rate distributions were obtained for simulated Thermal Protection System (TPS) tile arrays on the curved surface test apparatus of the Langley 8-Foot High Temperature Tunnel at Mach 6.6. The results indicated that the chine gap pressures varied inversely with gap width because larger gap widths allowed greater venting from the gap to the lower model side pressures. Lower gap pressures caused greater flow ingress from the surface and increased gap heating. Generally, gap heating was greater in the longitudinal gaps than in the circumferential gaps. Gap heating decreased with increasing gap depth. Circumferential gap heating at the mid-depth was generally less than about 10 percent of the external surface value. Gap heating was most severe at local T-gap junctions and tile-to-tile forward-facing steps that caused the greatest heating from flow impingement. The use of flow stoppers at discrete locations reduced heating from flow impingement. The use of flow stoppers at discrete locations reduced heating in most gaps but increased heating in others. Limited use of flow stoppers or gap filler in longitudinal gaps could reduce gap heating in open circumferential gaps in regions of high surface pressure gradients.

  18. STS-27R OV-104 Orbiter TPS damage review team, volume 1

    NASA Technical Reports Server (NTRS)

    Thomas, John W. (Compiler)

    1989-01-01

    Following the return to earth on December 2, 1988, of Orbiter OV-104, Atlantis, it was observed that there was substantial Thermal Protection System (TPS) tile damage present on the lower right fuselage and wing. Damage sites were more numerous than on previous flights and conversely, there was almost no damage present on Atlantis' left side. A review team investigated the cause beginning with a detailed inspection of the Atlantis TPS damage, and a review of related inspection reports to establish an indepth anomaly definition. An exhaustive data review followed. A fault tree and several failure scenarios were developed. Finally, the failure scenarios were categorized as either not possible, possible but not probable, or probable. This and other information gained during the review formed the basis for the team's findings and recommendations. The team concluded that the most probable cause of the severe STS-27R Orbiter tile damage is that the ablative insulating material covering the RH SRB Nose Cap dislodged and struck the Orbiter tile near 85 seconds into flight and possibly that debris from other sources, including repaired insulation and missing joint cork, caused minor tile damage. Findings are presented, and recommendations that are believed pertinent to minimizing the potential for inflight debris are described.

  19. Plug-and-play design approach to smart harness for modular small satellites

    NASA Astrophysics Data System (ADS)

    Mughal, M. Rizwan; Ali, Anwar; Reyneri, Leonardo M.

    2014-02-01

    A typical satellite involves many different components that vary in bandwidth demand. Sensors that require a very low data rate may reside on a simple two- or three-wire interface such as I2C, SPI, etc. Complex sensors that require high data rate and bandwidth may reside on an optical interface. The AraMiS architecture is an enhanced capability architecture with different satellite configurations. Although keeping the low-cost and COTS approach of CubeSats, it extends the modularity concept as it also targets different satellite shapes and sizes. But modularity moves beyond the mechanical structure: the tiles also have thermo-mechanical, harness and signal-processing functionalities. Further modularizing the system, every tile can also host a variable number of small sensors, actuators or payloads, connected using a plug-and-play approach. Every subsystem is housed in a small daughter board and is supplied, by the main tile, with power and data distribution functions, power and data harness, mechanical support and is attached and interconnected with space-grade spring-loaded connectors. The tile software is also modular and allows a quick adaptation to specific subsystems. The basic software for the CPU is properly hardened to guarantee high level of radiation tolerance at very low cost.

  20. KSC-08pd1968

    NASA Image and Video Library

    2008-07-14

    CAPE CANAVERAL, Fla. – In the tile shop at NASA's Kennedy Space Center, a Boeing Replacement Insulation 18, or BRI-18, tile bakes in a 2,200-degree oven to cure the ceramic coating. The baking is part of the process to prepare the tiles for installation on space shuttles. BRI-18 is the strongest material used for thermal insulation on the orbiters and, when coated to produce toughened unipiece fibrous insulation, provides a tile with extremely high-impact resistance. It is replacing other tiles on areas of the vehicle where impact risk is high, such as the landing gear doors, the wing leading edge and the external tank doors. Photo credit: NASA/Jim Grossmann

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