WorldWideScience

Sample records for lightweight planes lift-off

  1. Large-Area Laser-Lift-Off Processing in Microelectronics

    Science.gov (United States)

    Delmdahl, R.; Pätzel, R.; Brune, J.

    Laser lift-off is an enabling technology for microelectronics growth markets such as light emitting diodes, densely packaged semiconductor devices, and flexible displays. For example, thin film transistor structures fabricated on top of polymer layers spun on glass carriers must be delaminated from rigid substrates to create lightweight and rugged flexible displays on polymers. Low-thermal-budget processes are generically required to protect adjacent functional films. Excimer lasers provide short UV wavelength and short pulse duration required for highly-localized energy coupling. The high output power of excimer lasers enables a large processing footprint and the high-throughput rates needed in mass manufacturing.

  2. APOLLO 14: Lift off from lunar surface

    Science.gov (United States)

    1974-01-01

    APOLLO 14: The lunar module 'Falcon' lifts off from the lunar surface From the film documentary 'APOLLO 14: 'Mission to Fra Mauro'', part of a documentary series on the APOLLO missions made in the early '70's and narrated by Burgess Meredith. APOLO 14: Third manned lunar landing with Alan B. Shepard, Jr.,Stuart A. Roosa, and Edgar D. Mitchell. Landed in the Fra Mauro area on Ferurary 5, 1971; performed EVA, deployed lunar experiments, returned lunar samples. Mission Duration 216 hrs 1 min 58 sec

  3. Lift-Off Processing and Superconducting Circuit Coherence

    Science.gov (United States)

    Quintana, C. M.; Megrant, A.; Dunsworth, A.; Chen, Zijun; Chiaro, B.; Barends, R.; Campbell, B.; Chen, Yu; Jeffrey, E.; Kelly, J.; Mutus, J. Y.; Neill, C.; O'Malley, P. J. J.; Roushan, P.; Sank, D.; Wenner, J.; White, T. C.; Cleland, A. N.; Martinis, John M.

    2014-03-01

    As superconducting circuit coherence continues to increase, careful attention must be paid to device fabrication techniques. Substantial evidence points to dielectric loss from two-level state defects in thin amorphous interfacial regions as a limiting relaxation mechanism for superconducting qubits. Transmon qubits have traditionally been fabricated using lift-off aluminum deposited together with their Josephson junctions; however, improved coherence times have recently been found in transmons which use lift-off metal for only a small fraction of the qubit. To better understand this improvement and predict any remaining limits imposed by the incorporation of lift-off, we characterize the increased loss found in coplanar waveguide resonators formed with lift-off metal. We vary surface treatment such as oxygen ashing and ion milling, and study the effects of double-angle evaporation, e-beam resist residue, and surface roughness on resonator quality factors.

  4. Advanced Epitaxial Lift-Off Quantum Dot Photovoltaic Devices Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop a high-efficiency, triple-junction, epitaxial lift-off (ELO) solar cell by incorporating quantum dots (QDs) within the current-limiting...

  5. Hydrofoils: optimum lift-off speed for sailboats.

    Science.gov (United States)

    Baker, R M

    1968-12-13

    For a hydrofoil sailboat there is a unique optimum lift-off speed. Before this speed is reached, if there are no parasitic vertical hydrofoil appendages, the submerged or partially submerged hydrofoils increase drag and degrade performance. As soon as this speed is reached and the hydrofoils are fully and promptly deployed, the performance of a hydrofoil-borne craft is significantly improved. At speeds exceeding optimum lift-off speed, partially submerged hydrofoils impair performance if there is no significant effect of loading on the hydrofoil lift-to-drag ratio.

  6. Double-Sided Opportunities Using Chemical Lift-Off Lithography.

    Science.gov (United States)

    Andrews, Anne M; Liao, Wei-Ssu; Weiss, Paul S

    2016-08-16

    We discuss the origins, motivation, invention, development, applications, and future of chemical lift-off lithography, in which a specified pattern of a self-assembled monolayer is removed, i.e., lifted off, using a reactive, patterned stamp that is brought into contact with the monolayer. For Au substrates, this process produces a supported, patterned monolayer of Au on the stamp in addition to the negative pattern in the original molecular monolayer. Both the patterned molecular monolayer on the original substrate and the patterned supported metal monolayer on the stamp are useful as materials and for further applications in sensing and other areas. Chemical lift-off lithography effectively lowers the barriers to and costs of high-resolution, large-area nanopatterning. On the patterned monolayer side, features in the single-nanometer range can be produced across large (square millimeter or larger) areas. Patterns smaller than the original stamp feature sizes can be produced by controlling the degree of contact between the stamp and the lifted-off monolayer. We note that this process is different than conventional lift-off processes in lithography in that chemical lift-off lithography removes material, whereas conventional lift-off is a positive-tone patterning method. Chemical lift-off lithography is in some ways similar to microtransfer printing. Chemical lift-off lithography has critical advantages in the preparation of biocapture surfaces because the molecules left behind are exploited to space and to orient functional(ized) molecules. On the supported metal monolayer side, a new two-dimensional material has been produced. The useful important chemical properties of Au (vis-à-vis functionalization with thiols) are retained, but the electronic and optical properties of bulk Au or even Au nanoparticles are not. These metal monolayers do not quench excitation and may be useful in optical measurements, particularly in combination with selective binding due to

  7. Epitaxial lift-off technology of GaAs multijunction solar cells

    Science.gov (United States)

    Knyps, P.; Dumiszewska, E.; Kaszub, W.; Przewłoka, A.; Strupinski, W.

    2016-12-01

    Epitaxial lift-off (ELO) is a process which enables the removal of solar cell structures (one junction GaAs, two junction GaAs/InGaP or three junction GaAs/InGaAs/InGaP) from the substrate on which they are grown and their transfer onto lightweight carriers such as metal or polymeric insulator films. The said solar cells exhibit superior power conversion efficiency compared with alternative single-junction photovoltaic cell designs such as those based on crystalline Si, copper indium gallium sulfide (CIGS) or CdTe. The major advantage of ELO solar cells is the potential for wafer reuse, which can enable significant manufacturing cost reduction by minimizing the consumption of expensive wafers. Here in this work we have grown one junction GaAs solar cells on GaAs (100) substrates. A 10 nm thick AlAs layer has been used as a release layer, which has been selectively etched in HF solution. We have investigated different methods of transferring thin films onto polymer and copper foils, including the usage of temporary mounting adhesives and electro-conductive pastes. Lift-off has been demonstrated to be a very promising technique for producing affordable solar cells with a very high efficiency of up to 30%.

  8. In-plane Shear Joint Capacity of Pracast Lightweight Aggregate Concrete Elements

    DEFF Research Database (Denmark)

    Larsen, Henning; Goltermann, Per; Scherfig, Søren;

    1996-01-01

    The paper establishes and documents formulas for the in-plane shear capacity between precast elements of lightweight aggregate concrete with open structure. The joints investigated are rough or toothed and have all been precracked prior to the testing in order to obtain realistic test results...

  9. Lift-off dynamics in a simple jumping robot

    CERN Document Server

    Aguilar, Jeffrey; Wiesenfeld, Kurt; Goldman, Daniel I

    2012-01-01

    We study vertical jumping in a simple robot comprising an actuated mass-spring arrangement. The actuator frequency and phase are systematically varied to find optimal performance. Optimal jumps occur above and below (but not at) the robot's resonant frequency $f_0$. Two distinct jumping modes emerge: a simple jump which is optimal above $f_0$ is achievable with a squat maneuver, and a peculiar stutter jump which is optimal below $f_0$ is generated with a counter-movement. A simple dynamical model reveals how optimal lift-off results from non-resonant transient dynamics.

  10. Laser polymerization-based novel lift-off technique

    Energy Technology Data Exchange (ETDEWEB)

    Bhuian, B. [Tyndall National Institute, Lee Maltings, Prospect Row, Cork (Ireland); Department of Microelectronic Engineering, University College Cork, Cork (Ireland); Winfield, R.J. [Tyndall National Institute, Lee Maltings, Prospect Row, Cork (Ireland)], E-mail: richard.winfield@tyndall.ie; Crean, G.M. [Tyndall National Institute, Lee Maltings, Prospect Row, Cork (Ireland); Department of Microelectronic Engineering, University College Cork, Cork (Ireland)

    2009-03-01

    The fabrication of microstructures by two-photon polymerization has been widely reported as a means of directly writing three-dimensional nanoscale structures. In the majority of cases a single point serial writing technique is used to form a polymer model. Single layer writing can also be used to fabricate two-dimensional patterns and we report an extension of this capability by using two-photon polymerization to form a template that can be used as a sacrificial layer for a novel lift-off process. A Ti:sapphire laser, with wavelength 795 nm, 80 MHz repetition rate, 100 fs pulse duration and an average power of 700 mW, was used to write 2D grid patterns with pitches of 0.8 and 1.0 {mu}m in a urethane acrylate resin that was spun on to a lift-off base layer. This was overcoated with gold and the grid lifted away to leave an array of gold islands. The optical transmission properties of the gold arrays were measured and found to be in agreement with a rigorous coupled-wave analysis simulation.

  11. Body-rock or lift-off in flow

    CERN Document Server

    Smith, Frank T

    2013-01-01

    Conditions are investigated under which a body lying at rest or rocking on a solid horizontal surface can be removed from the surface by hydrodynamic forces or instead continues rocking. The investigation is motivated by recent observations on Martian dust movement as well as other small- and large-scale applications. The nonlinear theory of fluid-body interaction here has unsteady motion of an inviscid fluid interacting with a moving thin body. Various shapes of body are addressed together with a range of initial conditions. The relevant parameter space is found to be subtle as evolution and shape play substantial roles coupled with scaled mass and gravity effects. Lift-off of the body from the surface generally cannot occur without fluid flow but it can occur either immediately or within a finite time once the fluid flow starts up: parameters for this are found and comparisons are made with Martian observations.

  12. Polymer-Pen Chemical Lift-Off Lithography.

    Science.gov (United States)

    Xu, Xiaobin; Yang, Qing; Cheung, Kevin M; Zhao, Chuanzhen; Wattanatorn, Natcha; Belling, Jason N; Abendroth, John M; Slaughter, Liane S; Mirkin, Chad A; Andrews, Anne M; Weiss, Paul S

    2017-05-10

    We designed and fabricated large arrays of polymer pens having sub-20 nm tips to perform chemical lift-off lithography (CLL). As such, we developed a hybrid patterning strategy called polymer-pen chemical lift-off lithography (PPCLL). We demonstrated PPCLL patterning using pyramidal and v-shaped polymer-pen arrays. Associated simulations revealed a nanometer-scale quadratic relationship between contact line widths of the polymer pens and two other variables: polymer-pen base line widths and vertical compression distances. We devised a stamp support system consisting of interspersed arrays of flat-tipped polymer pens that are taller than all other sharp-tipped polymer pens. These supports partially or fully offset stamp weights thereby also serving as a leveling system. We investigated a series of v-shaped polymer pens with known height differences to control relative vertical positions of each polymer pen precisely at the sub-20 nm scale mimicking a high-precision scanning stage. In doing so, we obtained linear-array patterns of alkanethiols with sub-50 nm to sub-500 nm line widths and minimum sub-20 nm line width tunable increments. The CLL pattern line widths were in agreement with those predicted by simulations. Our results suggest that through informed design of a stamp support system and tuning of polymer-pen base widths, throughput can be increased by eliminating the need for a scanning stage system in PPCLL without sacrificing precision. To demonstrate functional microarrays patterned by PPCLL, we inserted probe DNA into PPCLL patterns and observed hybridization by complementary target sequences.

  13. Ion implantation of diamond: Damage, doping, and lift-off

    Energy Technology Data Exchange (ETDEWEB)

    Parikh, N.R.; McGucken, E.; Swanson, M.L. [North Carolina Univ., Chapel Hill, NC (United States). Dept. of Physics and Astronomy; Hunn, J.D.; White, C.W.; Zuhr, R.A. [Oak Ridge National Lab., TN (United States)

    1993-09-01

    In order to make good quality economical diamond electronic devices, it is essential to grow films and to dope these films to obtain n- and p- type conductivity. This review talk discuss first doping by ion implantation plus annealing of the implantation damage, and second flow to make large area single crystal diamonds. C implantation damage below an estimated Frenkel defect concentration of 7% could be recovered almost completely by annealing at 950C. For a defect concentration between 7 and 10%, a stable damage form of diamond (``green diamond``) was formed by annealing. At still higher damage levels, the diamond graphitized. To introduce p-type doping, we have co-implanted B and C into natural diamond at 77K, followed by annealing up to 1100C. The resulting semiconducting material has electrical properties similar to those of natural B-doped diamond. To create n-type diamond, we have implanted Na{sup +}, P+ and As{sup +} ions and have observed semiconducting behavior. This has been compared with carbon or noble element implantation, in an attempt to isolate the effect of radiation damage. Recently, in order to obtain large area signal crystals, we have developed a novel technique for removing thin layers of diamond from bulk or homoepitaxial films. This method consists of ion implantation, followed by selective etching. High energy (4--5 MeV) implantation of carbon or oxygen ions creates a well-defined layer of damaged diamond buried at a controlled depth. This layer is graphitized and selectivity etched either by heating at 550C in an oxygen ambient or by electrolysis. This process successfully lifts off the diamond plate above the graphite layer. The lift-off method, combined with well-established homoepitaxial growth processes, has potential for fabrication of large area single-crystal diamond sheets.

  14. Lift off for second pair of Cluster II spacecraft

    Science.gov (United States)

    2000-09-01

    At 13.13 CEST, (17.13 Baikonur Time - 13.13 CEST) ) a Soyuz-Fregat launch vehicle provided by the French-Russian Starsem consortium lifted off with Cluster satellites FM 5 (Rumba) and FM 8 (Tango). Approximately 75 minutes into the mission, the Fregat transfer module fired for a second time to insert the spacecraft into a 250 km x 18,000 km separation orbit. About 20 minutes later, the ground station in Kiruna, Sweden, confirmed that the satellites had successfully separated from the Fregat and were now flying in good health. "This second perfect launch within less than four weeks means that Cluster is on track for a highly successful mission," said Professor Roger-Maurice Bonnet, ESA science director. "We are now looking forward to receiving the unique three-dimensional data that will give new understanding of the interaction between the Sun and Earth." Over the next week, Rumba and Tango will participate in a complex series of orbital manoeuvres in order to rendezvous with the other spacecraft in the Cluster flotilla (Salsa and Samba). The quartet will then undergo three months of instrument and system commissioning before beginning their two-year scientific mission. For regular status reports on the mission dial +49.6151.90.2609 at ESA/ESOC.

  15. Reduction of lift-off effect in high-frequency apparent eddy current conductivity spectroscopy

    Science.gov (United States)

    Abu-Nabah, Bassam A.

    2017-05-01

    Eddy current spectroscopy is capable of mapping conductivities and thicknesses of layered structures due to its frequency-dependent penetration depth. High-frequency apparent eddy current conductivity (AECC) spectroscopy applications typically mandate covering a frequency range beyond 10 MHz to capture depth-dependent conductivity profiles. Following the standard four-point linear system calibration method beyond 10 MHz makes it difficult to achieve accurate AECC measurements due to spurious self- and stray-capacitive effects where complex eddy current coil impedance variation with lift-off becomes more nonlinear. In this study, two different approaches are presented to reduce AECC measurement sensitivity to lift-off. First, a nonlinear lift-off correction is developed as a function of measured apparent eddy current lift-off. Second, a semi-quadratic system calibration is developed to capture the lift-off curvature as a function of frequency and hence minimizes the measurement sensitivity to lift-off variations. Presented calibration techniques allow more robust AECC measurements up to 80-100 MHz with one-order of magnitude improvement in accuracy in comparison to the use of standard four-point linear system calibration in a lift-off range of  ±25.4 µm.

  16. Effects of Injector Conditions on the Flame Lift-Off Length of DI Diesel Sprays

    Energy Technology Data Exchange (ETDEWEB)

    D. L. Siebers; B. S. Higgins

    2000-07-01

    The effects of injection pressure and orifice diameter on the lift-off length of a direct-injection (DI) diesel spray (defined as the farthest upstream location of high temperature combustion) were investigated using a natural light emission imaging technique. The lift-off length experiments were conducted in a constant-volume combustion vessel under quiescent, heavy-duty DI diesel engine conditions using a Phillips research grade No.2 diesel fuel. The results show that natural light emission at 310 nm provides an excellent marker of the lift-off length. At this location, natural light emission at 310 nm is dominated by OH chemiluminescence generated by high-temperature combustion chemistry. Lift-off lengths determined from images of natural light emission at 310 nm show that as either injection pressure (i.e., injection velocity) or orifice diameter increase, the lift-off length increases. The observed lift-off length increase was linearly dependent on injection velocity, the same dependency as previously noted for gas jets. The lift-off length increase with increasing orifice diameter, however, is different than the independence of lift-off length on orifice diameter noted for gas jets An important overall observation was made by considering the lift-off length data in conjunction with data from recent investigations of liquid-phase fuel penetration and spray development. The combined data suggests that a systematic evolution of the relationship and interaction between various processes in a DI diesel spray has been occurring over time, as injection pressures have been increased and orifice diameters reduced as part of efforts to meet emissions regulations. The trends observed may eventually help explain effects of parameters such as injection pressure and orifice diameter on emissions.

  17. Time resolved measurements of particle lift off from the wall in a turbulent water channel flow

    Science.gov (United States)

    van Hout, Rene; Rabencov, Boris; Arca, Javier

    2011-11-01

    Time-Resolved Particle Image Velocimetry (TR-PIV) and digital holography measurements were carried out in a dilute particle-laden flow tracking both Polystyrene Spheres (PS, ~0.583 mm, d+ ~ 10) as well as resolving the instantaneous velocity field of the turbulent flow. Measurements were performed in a closed loop, transparent, square channel facility (50x50 mm2) at 127.5cm from the inlet with bulk water velocity 0.3 m/s (Reh = 7353) and friction velocity 0.0174 m/s. Data were captured at 1 kHz, corresponding to a time scale 5x smaller than the flow's viscous scale. Single view digital holographic cinematography was used to track the 3D PS motion inside the VOI (17x17x50 mm3) including the wall bottom. TR-PIV in a vertical plane (29.3x29.3 mm2) oriented along the channel's centerline imaged PS together with flow tracers. Discrimination was based on their size difference. Instantaneous sequences of PS plotted on the spatial velocity, vorticity and swirling strength maps showed the effect of turbulent flow structures and resulting particle movement. Results are presented for particles that lift off from the bottom wall as a result of complex interaction with ejection and sweep motions.

  18. Bending in HVPE GaN free-standing films: effects of laser lift-off, polishing and high-pressure annealing

    Energy Technology Data Exchange (ETDEWEB)

    Paskova, T. [Department of Physics and Measurement Technology, Linkoeping University, 581 83 Linkoeping (Sweden); Institute of Solid State Physics, University of Bremen, 28359 Bremen (Germany); Darakchieva, V.; Paskov, P.P.; Monemar, B. [Department of Physics and Measurement Technology, Linkoeping University, 581 83 Linkoeping (Sweden); Bukowski, M.; Suski, T. [High Pressure Research Center, Unipress, Polish Academy of Sciences, 01-142 Warsaw (Poland); Ashkenov, N.; Schubert, M. [Fakultaet fuer Physik and Geowissenschaften, Universitaet Leipzig, 04103 Leipzig (Germany); Hommel, D. [Institute of Solid State Physics, University of Bremen, 28359 Bremen (Germany)

    2006-06-15

    We have studied the effects of laser lift-off and polishing processes on the bending of free-standing HVPE grown GaN thick films. Their structural characteristics were accessed by reciprocal space mapping and lattice parameters measurements as well as by Raman scattering and photoluminescence. The in-plane strain difference between the two faces was found to have determining effect on the bending of the free-standing films. Removing the high-defect-density near-interface region either by melting caused by laser lift-off, or by polishing, or by point defects dissociation caused by high-pressure annealing was found to lead to flattening of the strain distribution along the film thickness and a significant reduction of the bending of the free-standing films. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  19. Lift Off for first pair of Cluster II spacecraft

    Science.gov (United States)

    2000-07-01

    At 14.39 CEST, a Soyuz-Fregat launch vehicle provided by the French-Russian Starsem consortium lifted off with FM 6 and FM 7, the first pair of Cluster II satellites. Approximately 90 minutes into the mission, the rocket's Fregat fourth stage fired for a second time to insert the spacecraft into a 240 km - 18,000 km parking orbit. A few minutes later, the ground station in Kiruna, Sweden, acquired the two spacecraft and started to receive telemetry, confirming that the satellites had sucessfully separated from the Fregat and that they were now flying independently. "This has been an excellent start and we look forward to the second launch next month," said Professor Roger-Maurice Bonnet, ESA Director of Science. "Cluster is one of the key Cornerstone missions in our Horizons 2000 long-term scientific programme and it will provide unique insights that will revolutionise our understanding of near-Earth space." ESA's Cluster II project manager, Dr John Ellwood, paid tribute to the hundreds of scientists and engineers in many countries who have worked so hard to rebuild the four Cluster satellites since the tragic loss of the first group in 1996. "Without the dedication and teamwork of these people, today's success would not have been possible," he said. "Only three years after we began the Cluster II programme, we are already starting to see the fruits of all our efforts." Cluster II deputy project manager, Alberto Gianolio, also expressed his full satisfaction for the successful launch. "This launch marks a milestone in the cooperation between the European Space Agency and our Russian partners. We are looking forward to the continuation of this fruitful joint effort in the years to come". UK Winner For Cluster Competition - Rumba, Salsa, Samba, Tango into space! The winner of ESA's "Name The Cluster Quartet" competition was announced today, during a special launch event for the media at the European Space Operations Centre (ESOC) in Darmstadt, Germany. After an

  20. Reliable fabrication of plasmonic nanostructures without an adhesion layer using dry lift-off

    Science.gov (United States)

    Chen, Yiqin; Li, Zhiqin; Xiang, Quan; Wang, Yasi; Zhang, Zhiqiang; Duan, Huigao

    2015-10-01

    Lift-off is the most commonly used pattern-transfer method to define lithographic plasmonic metal nanostructures. A typical lift-off process is realized by dissolving patterned resists in solutions, which has the limits of low yield when not using adhesion layers and incompatibility with the fabrication of some specific structures and devices. In this work, we report an alternative ‘dry’ lift-off process to obtain metallic nanostructures via mechanical stripping by using the advantage of poor adhesion between resists and noble metal films. We show that this dry stripping lift-off method is effective for both positive- and negative-tone resists to fabricate sparse and densely-packed plasmonic nanostructures, respectively. In particular, this method is achieved without using an adhesion layer, which enables the mitigation of plasmon damping to obtain larger field enhancement. Dark-field scattering, one-photon luminescence and surface-enhanced Raman scattering measurements were performed to demonstrate the improved quality factor of the plasmonic nanostructures fabricated by this dry lift-off process.

  1. A Lift-Off-Tolerant Magnetic Flux Leakage Testing Method for Drill Pipes at Wellhead

    Science.gov (United States)

    Wu, Jianbo; Fang, Hui; Li, Long; Wang, Jie; Huang, Xiaoming; Kang, Yihua; Sun, Yanhua; Tang, Chaoqing

    2017-01-01

    To meet the great needs for MFL (magnetic flux leakage) inspection of drill pipes at wellheads, a lift-off-tolerant MFL testing method is proposed and investigated in this paper. Firstly, a Helmholtz coil magnetization method and the whole MFL testing scheme are proposed. Then, based on the magnetic field focusing effect of ferrite cores, a lift-off-tolerant MFL sensor is developed and tested. It shows high sensitivity at a lift-off distance of 5.0 mm. Further, the follow-up high repeatability MFL probing system is designed and manufactured, which was embedded with the developed sensors. It can track the swing movement of drill pipes and allow the pipe ends to pass smoothly. Finally, the developed system is employed in a drilling field for drill pipe inspection. Test results show that the proposed method can fulfill the requirements for drill pipe inspection at wellheads, which is of great importance in drill pipe safety. PMID:28117721

  2. A Lift-Off-Tolerant Magnetic Flux Leakage Testing Method for Drill Pipes at Wellhead

    Directory of Open Access Journals (Sweden)

    Jianbo Wu

    2017-01-01

    Full Text Available To meet the great needs for MFL (magnetic flux leakage inspection of drill pipes at wellheads, a lift-off-tolerant MFL testing method is proposed and investigated in this paper. Firstly, a Helmholtz coil magnetization method and the whole MFL testing scheme are proposed. Then, based on the magnetic field focusing effect of ferrite cores, a lift-off-tolerant MFL sensor is developed and tested. It shows high sensitivity at a lift-off distance of 5.0 mm. Further, the follow-up high repeatability MFL probing system is designed and manufactured, which was embedded with the developed sensors. It can track the swing movement of drill pipes and allow the pipe ends to pass smoothly. Finally, the developed system is employed in a drilling field for drill pipe inspection. Test results show that the proposed method can fulfill the requirements for drill pipe inspection at wellheads, which is of great importance in drill pipe safety.

  3. Analysis of sand particles' lift-off and incident velocities in wind-blown sand flux

    Institute of Scientific and Technical Information of China (English)

    Tian-Li Bo; Xiao-Jing Zheng; Shao-Zhen Duan; Yi-Rui Liang

    2013-01-01

    In the research of windblown sand movement,the lift-off and incident velocities of saltating sand particles play a significant role in bridging the spatial and temporal scales from single sand particle's motion to windblown sand flux.In this paper,we achieved wind tunnel measurements of the movement of sand particles near sand bed through improving the wind tunnel experimental scheme of paticle image velocimetry (PIV) and data processing method.And then the influence of observation height on the probability distributions of lift-off and incident velocities of sand particles was analyzed.The results demonstrate that the observation height has no obvious influence on the distribution pattern of the lift-off and incident velocities of sand particles,i.e.,the probability distribution of horizontal and vertical velocities of lift-off and incident sand particles follow a Gaussian distribution and a negative exponential distribution,respectively.However,it influences the center of the Gaussian distribution,the decay constant and the amplitude of the negative exponential distribution.

  4. Patterning of oxide-hardened gold black by photolithography and metal lift-off

    Science.gov (United States)

    Deep Panjwani; Mehmet Yesiltas; Janardan Nath; D.E. Maukonen; Imen Rezadad; Evan M. Smith; R.E. Peale; Carol Hirschmugl; Julia Sedlmair; Ralf Wehlitz; Miriam Unger; Glenn Boreman

    2014-01-01

    A method to pattern infrared-absorbing gold black by conventional photolithography and lift-off is described. A photo-resist pattern is developed on a substrate by standard photolithography. Gold black is deposited over the whole by thermal evaporation in an inert gas at

  5. Sputtered Pt electrode structures with smoothly tapered edges by bi-layer resist lift-off

    Energy Technology Data Exchange (ETDEWEB)

    Preiss, Elisabeth M., E-mail: elisabeth.preiss@de.bosch.com [Robert Bosch GmbH, Corporate Sector Research and Advance Engineering, Robert-Bosch-Campus 1, 71272 Renningen (Germany); Saarland University, Lab for Micromechanics, Microfluidics, and Microactuators, 66123 Saarbruecken (Germany); Krauss, Andreas [Robert Bosch GmbH, Corporate Sector Research and Advance Engineering, Robert-Bosch-Campus 1, 71272 Renningen (Germany); Seidel, Helmut [Saarland University, Lab for Micromechanics, Microfluidics, and Microactuators, 66123 Saarbruecken (Germany)

    2015-12-31

    A lift-off process using a bi-layer resist consisting of an image reversal resist on top and a lift-off resist at the bottom was used to structure Ti–Pt thin films. DC magnetron sputtered metal films patterned by this process show ultra smooth edges, ideal for applications such as interdigitated electrodes in resistive gas sensors including thin-film based sensitive coatings with thicknesses below 100 nm. Profiles of processed structures were analyzed by scanning electron microscopy and surface profilometer. The thickness profile and structure width were controlled by using different resist thicknesses and undercut lengths. Results were compared with iterative simulations by a geometric shadowing model, predicting undersputtering length and profile structure of the experimentally manufactured samples in good agreement. Target-to-substrate distance variation was found to have only a minor influence on the sputtering result. - Highlights: • Ti–Pt electrode structures were prepared using sputtering bi-layer-resist lift-off. • Prepared lift-off electrodes can be used for good overgrowth of thin films. • Ultra-smoothly tapered edges were controlled by the process parameters. • Simulations using a geometric shadowing model confirm our experimental results.

  6. "Literacy Lift-Off": An Experimental Evaluation of a Reading Recovery Programme on Literacy Skills and Reading Self-Concept

    Science.gov (United States)

    Higgins, Edel; Fitzgerald, Johanna; Howard, Siobhán

    2015-01-01

    Worldwide, considerable emphasis is currently being placed on the provision of appropriate classroom-based preventative interventions and in-class literacy support, in preference to withdrawal methods of educational support. Many schools in Ireland are currently implementing Literacy Lift-Off in their classrooms. Literacy Lift-Off is an adaption…

  7. LASER LIFT-OFF OF GaN THIN FILMS FROM SAPPHIRE SUBSTRATES

    Institute of Scientific and Technical Information of China (English)

    J. Xu; R. Zhang; Y.P. Wang; X.Q. Xiu; S.L. Gu; B. Shen; Y. Shi; Z.G. Liu; Y.D. Zheng

    2001-01-01

    Gallium Nitride film was successfully separated from sapphire substrate by laser radi-ation. The absorption of the 248nm radiation by the GaN at the interface results inrapid thermal decomposition of the interfacial layer, yielding metallic Ga and N2 gas.The substrate can be easily removed by heating above the Ga melting point (29℃).X-ray diffraction, atomic force microscopy and Photoluminescence of GaN before andafter lift-off process have been performed, which demonstrated that the separation andtransfer process do not alter the structural quality of the GaN films. And further dis-cussions on the threshold energy and crack-free strategies of laser lift-off process havealso been presented.

  8. Epitaxial lift-off GaAs solar cell from a reusable GaAs substrate

    Energy Technology Data Exchange (ETDEWEB)

    Geelen, A. van [Nijmegen Univ. (Netherlands). Res. Inst. for Mater.; Hageman, P.R. [Nijmegen Univ. (Netherlands). Res. Inst. for Mater.; Bauhuis, G.J. [Nijmegen Univ. (Netherlands). Res. Inst. for Mater.; Rijsingen, P.C. van [Nijmegen Univ. (Netherlands). Res. Inst. for Mater.; Schmidt, P. [Nijmegen Univ. (Netherlands). Res. Inst. for Mater.; Giling, L.J. [Nijmegen Univ. (Netherlands). Res. Inst. for Mater.

    1997-03-01

    Modifications to the existing epitaxial lift-off (ELO) method are described, which enable lift-off of large area devices (like solar cells). With the modified ELO method crack-free III-V films were obtained, up to 2 inch, in diameter and 1-6 {mu}m thick. For the first time epitaxial lift-off GaAs solar cells were made which contained an etch sensitive Al{sub 0.85}Ga{sub 0.15}As window layer. An energy conversion efficiency of 9.9% (AM1.5Gx1) was measured for the ELO GaAs cells. Compared to the thick GaAs reference cell, ELO cells still suffer from a low fill factor due to series and shunt resistances. Current GaAs ELO cells represent a power to weight ratio of 200 W kg{sup -1}. Because of the high selectivity of the ELO method, GaAs substrates remain unaffected after ELO. Reuse of a GaAs substrate after ELO was investigated in order to reduce the cost of III-V solar cell modules. With a simple cleaning procedure, GaAs substrates could be used at least four times without degradation of the minority carrier lifetime or carrier mobility of the grown epilayers. (orig.)

  9. Space Shuttle Propulsion Systems Plume Modeling and Simulation for the Lift-Off Computational Fluid Dynamics Model

    Science.gov (United States)

    Strutzenberg, L. L.; Dougherty, N. S.; Liever, P. A.; West, J. S.; Smith, S. D.

    2007-01-01

    This paper details advances being made in the development of Reynolds-Averaged Navier-Stokes numerical simulation tools, models, and methods for the integrated Space Shuttle Vehicle at launch. The conceptual model and modeling approach described includes the development of multiple computational models to appropriately analyze the potential debris transport for critical debris sources at Lift-Off. The conceptual model described herein involves the integration of propulsion analysis for the nozzle/plume flow with the overall 3D vehicle flowfield at Lift-Off. Debris Transport Analyses are being performed using the Shuttle Lift-Off models to assess the risk to the vehicle from Lift-Off debris and appropriately prioritized mitigation of potential debris sources to continue to reduce vehicle risk. These integrated simulations are being used to evaluate plume-induced debris environments where the multi-plume interactions with the launch facility can potentially accelerate debris particles toward the vehicle.

  10. Catalyst Interface Engineering for Improved 2D Film Lift-Off and Transfer

    DEFF Research Database (Denmark)

    Wang, Ruizhi; Whelan, Patrick Rebsdorf; Braeuninger-Weimer, Philipp

    2016-01-01

    The mechanisms by which chemical vapor deposited (CVD) graphene and hexagonal boron nitride (h-BN) films can be released from a growth catalyst, such as widely used copper (Cu) foil, are systematically explored as a basis for an improved lift-off transfer. We show how intercalation processes allow...... is not only highly versatile but also yields graphene and h-BN films of high quality regarding surface contamination, layer coherence, defects, and electronic properties, without requiring additional post-transfer annealing. We highlight how such transfers rely on targeted corrosion at the catalyst interface...

  11. Method of lift-off patterning thin films in situ employing phase change resists

    Science.gov (United States)

    Bahlke, Matthias Erhard; Baldo, Marc A; Mendoza, Hiroshi Antonio

    2014-09-23

    Method for making a patterned thin film of an organic semiconductor. The method includes condensing a resist gas into a solid film onto a substrate cooled to a temperature below the condensation point of the resist gas. The condensed solid film is heated selectively with a patterned stamp to cause local direct sublimation from solid to vapor of selected portions of the solid film thereby creating a patterned resist film. An organic semiconductor film is coated on the patterned resist film and the patterned resist film is heated to cause it to sublime away and to lift off because of the phase change.

  12. Carbon nanotube assisted Lift off of GaN layers on sapphire

    Science.gov (United States)

    Long, Hao; Feng, Xiaohui; Wei, Yang; Yu, Tongjun; Fan, Shoushan; Ying, Leiying; Zhang, Baoping

    2017-02-01

    Laser lift off (LLO) was one of the most essential processes in fabrication of vertical GaN-based LEDs. However, traditional laser lift off of GaN on sapphire substrates needed high laser energy threshold, which deteriorated the GaN crystal. In this paper, it was found that inserting carbon nanotube between GaN and sapphire could effectively reduce the laser energy threshold in GaN LLO, from 1.5 J /cm2 of conventional GaN/sapphire to 1.3 J /cm2 of CNT inserted GaN/sapphire. The temperature distributions at the GaN/sapphire interfaces with and without CNTs were simulated by the finite elements calculation under laser irradiation. It was found that, due to the higher laser absorption coefficient of CNT, the CNT played as a powerful heating wire, sending out the thermal outside to elevate the GaN's temperature, and thus reduce the laser threshold for LLO. Raman and photoluminescence measurements indicated that residual stress of GaN membranes was as small as 0.3 GPa by the carbon nanotube assisted LLO. This work not only opens new application of CNTs, but also demonstrates the potential of high performance blue and green LEDs.

  13. GaN/metal/Si heterostructure fabricated by metal bonding and laser lift-off

    Institute of Scientific and Technical Information of China (English)

    Zhang Xiaoying; Ruan Yujiao; Chen Songyan; Li Cheng

    2009-01-01

    A process methodology has been adopted to transfer GaN thin films grown on sapphire substrates to Si substrates using metal bonding and laser lift-off techniques. After bonding, a single KrF (248 nm) excimer laser pulse was directed through the transparent sapphire substrates followed by low-temperature heat treatment to remove the substrates. The influence of bonding temperature and energy density of the excimer laser on the structure and optical properties of GaN films were investigated systemically. Atomic force microscopy, X-ray diffraction and photolumi-nescence measurements showed that (1) the quality of the GaN film was higher at a lower bonding temperature and lower energy density; (2) the threshold of the energy density of the excimer laser lift-off GaN was 300 mJ/cm~2. The root-mean-square roughness of the transferred GaN surface was about 50 nm at a bonding temperature of 400 ℃.

  14. Low-loss titanium dioxide waveguides and resonators using a dielectric lift-off fabrication process.

    Science.gov (United States)

    Evans, Christopher C; Liu, Chengyu; Suntivich, Jin

    2015-05-04

    We present a bi-layer lift-off fabrication approach to create low-loss amorphous titanium dioxide (TiO2) integrated optical waveguides and resonators for visible and near-infrared applications. This approach achieves single-mode waveguide losses as low as 7.5 dB/cm around 633 nm and 1.2 dB/cm around 1550 nm, a factor of 4 improvement over previous reports, without the need to optimize etching conditions. Depositing a secondary 260-nm TiO2 layer can reduce losses further, with the optimized process yielding micro-ring resonators with loaded quality factors as high as 1.5 × 10(5) around 1550 nm and 1.6×10(5) around 780 nm. These losses render our TiO2 devices suitable for visible and telecommunications applications; in addition, the simplicity of this lift-off approach is broadly applicable to other novel material platforms, particularly using near-visible wavelengths.

  15. Experimental analysis of sand particles' lift-off and incident velocities in wind-blown sand flux

    Institute of Scientific and Technical Information of China (English)

    Li Xie; Zhibao Dong; Xiaojing Zheng

    2005-01-01

    The probability distributions of sand particles' lift-off and incident velocities in a wind-blown sand flux play very important roles in the simulation of the wind-blown sand movement. In this paper, the vertical and the horizontal speeds of sand particles located at 1.0 mm above a sand-bed in a wind-blown sand flux are observed with the aid of Phase Doppler Anemometry (PDA) in a wind tunnel. Based on the experimental data, the probability distributions of not only the vertical lift-off speed but also the lift-off velocity as well as its horizontal component and the incident velocity as well as its vertical and horizontal components can be obtained by the equal distance histogram method. It is found, according to the results of the χ2-test for these probability distributions, that the probability density functions (pdf's) of the sand particles' lift-off and incident velocities as well as their vertical components are described by the Gamma density function with different peak values and shapes and the downwind incident and lift-off horizontal speeds, respectively, can be described by the lognormal and the Gamma density functions. These pdf's depend on not only the sand particle diameter but also the wind speed.

  16. Preparation of GaN-based cross-sectional TEM specimens by laser lift-off.

    Science.gov (United States)

    Zilan, Li; Xiaodong, Hu; Ke, Chen; Ruijuan, Nie; Xuhui, Luo; Xiaoping, Zhang; Tongjun, Yu; Bei, Zhang; Song, Chen; Zhijian, Yang; Zhizhong, Chen; Guoyi, Zhang

    2005-01-01

    Laser lift-off (LLO) technology is successfully used to prepare GaN-based TEM cross-sectional specimens. Detailed procedures of the method to prepare the specimens are demonstrated. Large thin areas suitable for TEM analysis were obtained. TEM images of the resulting GaN interface are studied, and the changes in structural quality are confined to approximately the first 250 nm of the epilayer. Clear TEM images of the whole epilayer and the InGaN quantum wells and the HRTEM images of the superlattice layer are demonstrated, showing that LLO is a quick and ideal method to study the crystal structure of the epilayer, especially if only the upper layers are of interest.

  17. Transparent, Flexible Piezoelectric Nanogenerator Based on GaN Membrane Using Electrochemical Lift-Off.

    Science.gov (United States)

    Kang, Jin-Ho; Jeong, Dae Kyung; Ryu, Sang-Wan

    2017-03-29

    A transparent and flexible piezoelectric nanogenerator (TF PNG) is demonstrated based on a GaN membrane fabricated by electrochemical lift-off. Under shear stress on the TF PNG by finger force (∼182 mN), the GaN membrane effectively undergoes normal stress and generates piezoelectric polarization along the c-axis, resulting in the generation of piezoelectric output from the TF PNG. Although the GaN layer is 315 times thinner than the flexible polyethylene terephthalate (PET) substrate, the low Young's modulus of PET allows the GaN membranes to absorb ∼41% of the applied strain energy, which leads to their large lattice deformation under extremely low applied stress. Maximum output voltage and current values of 4.2 V and 150 nA are obtained, and the time decay of the output voltage is discussed.

  18. Epitaxial lift-off for solid-state cavity quantum electrodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Greuter, Lukas; Najer, Daniel; Kuhlmann, Andreas V.; Starosielec, Sebastian; Warburton, Richard J. [Department of Physics, University of Basel, Klingelbergstrasse 82, Basel 4056 (Switzerland); Valentin, Sascha R.; Ludwig, Arne; Wieck, Andreas D. [Lehrstuhl für Angewandte Festkörperphysik, Ruhr-Universität Bochum, D-44780 Bochum (Germany)

    2015-08-21

    We demonstrate an approach to incorporate self-assembled quantum dots into a Fabry-Pérot-like microcavity. Thereby, a 3λ/4 GaAs layer containing quantum dots is epitaxially removed and attached by van der Waals bonding to one of the microcavity mirrors. We reach a finesse as high as 4100 with this configuration limited by the reflectivity of the dielectric mirrors and not by scattering at the semiconductor-mirror interface, demonstrating that the epitaxial lift-off procedure is a promising procedure for cavity quantum electrodynamics in the solid state. As a first step in this direction, we demonstrate a clear cavity-quantum dot interaction in the weak coupling regime with a Purcell factor in the order of 3. Estimations of the coupling strength via the Purcell factor suggest that we are close to the strong coupling regime.

  19. Epitaxial lift-off for solid-state cavity quantum electrodynamics

    CERN Document Server

    Greuter, Lukas; Kuhlmann, Andreas V; Valentin, Sascha; Ludwig, Arne; Wieck, Andreas D; Starosielec, Sebastian; Warburton, Richard J

    2015-01-01

    We present a new approach to incorporate self-assembled quantum dots into a Fabry-P\\'{e}rot-like microcavity. Thereby a 3$\\lambda$/4 GaAs layer containing quantum dots is epitaxially removed and attached by van der Waals bonding to one of the microcavity mirrors. We reach a finesse as high as 4,100 with this configuration limited by the reflectivity of the dielectric mirrors and not by scattering at the semiconductor - mirror interface, demonstrating that the epitaxial lift-off procedure is a promising procedure for cavity quantum electrodynamics in the solid state. As a first step in this direction, we demonstrate a clear cavity-quantum dot interaction in the weak coupling regime with a Purcell factor in the order of 3. Estimations of the coupling strength via the Purcell factor suggests that we are close to the strong coupling regime.

  20. Lift-off PMN-PT Thick Film for High Frequency Ultrasonic Biomicroscopy.

    Science.gov (United States)

    Zhu, Benpeng; Han, Jiangxue; Shi, Jing; Shung, K Krik; Wei, Q; Huang, Yuhong; Kosec, M; Zhou, Qifa

    2010-10-01

    Piezoelectric 0.65Pb(Mg(1/3)Nb(2/3))O(3)-0.35PbTiO(3) (PMN-35PT) thick film with a thickness of approximately 12 µm has been deposited on the platinum buffered Si substrate via a sol-gel composite method. The separation of the film from the substrate was achieved using a wet chemical method. The lifted-off PMN-35PT thick film exhibited good dielectric and ferroelectric properties. At 1 kHz, the dielectric constant and the dielectric loss were 3,326 and 0.037, respectively, while the remnant polarization was 30.0 µC/cm(2). A high frequency single element acoustic transducer fabricated with this film showed a bandwidth at -6 dB of 63.6% at 110 MHz.

  1. Carbon Nanotube Arrays with Strong Shear Binding-On and Easy Normal Lifting-Off

    Science.gov (United States)

    Qu, Liangti; Dai, Liming; Stone, Morley; Xia, Zhenhai; Wang, Zhong Lin

    2008-10-01

    The ability of gecko lizards to adhere to a vertical solid surface comes from their remarkable feet with aligned microscopic elastic hairs. By using carbon nanotube arrays that are dominated by a straight body segment but with curly entangled top, we have created gecko-foot mimetic dry adhesives that show macroscopic adhesive forces of ~100 newtons per square centimeter, almost 10 times that of a gecko foot, and a much stronger shear adhesion force than the normal adhesion force, to ensure strong binding along the shear direction and easy lifting in the normal direction. This anisotropic force distribution is due to the shear-induced alignments of the curly segments of the nanotubes. The mimetic adhesives can be alternatively binding-on and lifting-off over various substrates for simulating the walking of a living gecko.

  2. Dry Epitaxial Lift-Off for High Efficiency Solar Cells Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A new method of transferring epitaxially grown active films onto an inexpensive polymeric flexible carrier. Specifically, for making thin lightweight high efficiency...

  3. Double layer resist process scheme for metal lift-off with application in inductive heating of microstructures

    DEFF Research Database (Denmark)

    Ouattara, Lassana; Knutzen, Michael; Keller, Stephan Urs

    2010-01-01

    We present a new method to define metal electrodes on top of high-aspect-ratio microstructures using standard photolithography equipment and a single chromium mask. A lift-off resist (LOR) layer is implemented in an SU-8 photolithography process to selectively remove metal at the end of the proce...

  4. Multiple release layer study of the intrinsic lateral etch rate of the epitaxial lift-off process

    NARCIS (Netherlands)

    Voncken, M.M.J.; Schermer, J.J.; Bauhuis, G.J.; Mulder, P.; Larsen, P.K.

    2004-01-01

    The lateral etch rate of AlGaAs in HF in the 'Epitaxial Lift-Off' (ELO) process consists of two parts, an intrinsic and a radius-induced part. The intrinsic part is studied with a new approach in which multiple release layers are introduced in one sample. By letting an essential ELO process paramete

  5. Lift-Off: Using Reference Imagery and Freehand Sketching to Create 3D Models in VR.

    Science.gov (United States)

    Jackson, Bret; Keefe, Daniel F

    2016-04-01

    Three-dimensional modeling has long been regarded as an ideal application for virtual reality (VR), but current VR-based 3D modeling tools suffer from two problems that limit creativity and applicability: (1) the lack of control for freehand modeling, and (2) the difficulty of starting from scratch. To address these challenges, we present Lift-Off, an immersive 3D interface for creating complex models with a controlled, handcrafted style. Artists start outside of VR with 2D sketches, which are then imported and positioned in VR. Then, using a VR interface built on top of image processing algorithms, 2D curves within the sketches are selected interactively and "lifted" into space to create a 3D scaffolding for the model. Finally, artists sweep surfaces along these curves to create 3D models. Evaluations are presented for both long-term users and for novices who each created a 3D sailboat model from the same starting sketch. Qualitative results are positive, with the visual style of the resulting models of animals and other organic subjects as well as architectural models matching what is possible with traditional fine art media. In addition, quantitative data from logging features built into the software are used to characterize typical tool use and suggest areas for further refinement of the interface.

  6. MBE growth and design of II-VI heterostructures for epitaxial lift-off

    Energy Technology Data Exchange (ETDEWEB)

    Davidson, Ian A.; Vallance, Erin C.; Prior, Kevin A. [School of Engineering and Physical Science, Heriot-Watt University, Edinburgh (United Kingdom); Moug, Richard T.; Tamargo, Maria C. [Department of Chemistry, City College of New York, New York, NY (United States)

    2012-08-15

    Epitaxial lift-off (ELO) is a post-growth process that allows the active part of a semiconductor structure to be transferred from its growth substrate to a new one. This is a well established technique for III-V semiconductors, and has previously been demonstrated for ZnSe-based alloys grown on GaAs using a metastable MgS sacrificial layer, taking advantage of the huge difference in etch rates of MgS and ZnSe. We report here the first successful extension of this process to II-VI layers grown on InP by using a MgSe sacrificial layer. By using the correct etching conditions, MgSe has been found to work effectively as a sacrificial layer. 5 x 5 mm{sup 2} square pieces of material can be lifted and deposited on glass substrates without any deterioration in the structural or optical properties; as confirmed by optical microscopy and photoluminescence (PL) measurements. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Chondrocyte Behavior on Micropatterns Fabricated Using Layer-by-Layer Lift-Off: Morphological Analysis

    Directory of Open Access Journals (Sweden)

    Jameel Shaik

    2013-01-01

    Full Text Available Cell patterning has emerged as an elegant tool in developing cellular arrays, bioreactors, biosensors, and lab-on-chip devices and for use in engineering neotissue for repair or regeneration. In this study, micropatterned surfaces were created using the layer-by-layer lift-off (LbL-LO method for analyzing canine chondrocytes response to patterned substrates. Five materials were chosen based on our previous studies. These included: poly(dimethyldiallylammonium chloride (PDDA, poly(ethyleneimine (PEI, poly(styrene sulfonate (PSS, collagen, and chondroitin sulfate (CS. The substrates were patterned with these five different materials, in five and ten bilayers, resulting in the following multilayer nanofilm architectures: (PSS/PDDA5, (PSS/PDDA10; (CS/PEI4/CS, (CS/PEI9/CS; (PSS/PEI5, (PSS/PEI10; (PSS/Collagen5, (PSS/Collagen10; (PSS/PEI4/PSS, (PSS/PEI9/PSS. Cell characterization studies were used to assess the viability, longevity, and cellular response to the configured patterned multilayer architectures. The cumulative cell characterization data suggests that cell viability, longevity, and functionality were enhanced on micropatterned PEI, PSS, collagen, and CS multilayer nanofilms suggesting their possible use in biomedical applications.

  8. Multi-Stacked Supported Lipid Bilayer Micropatterning through Polymer Stencil Lift-Off

    Directory of Open Access Journals (Sweden)

    Yujie Zhu

    2015-08-01

    Full Text Available Complex multi-lamellar structures play a critical role in biological systems, where they are present as lamellar bodies, and as part of biological assemblies that control energy transduction processes. Multi-lamellar lipid layers not only provide interesting systems for fundamental research on membrane structure and bilayer-associated polypeptides, but can also serve as components in bioinspired materials or devices. Although the ability to pattern stacked lipid bilayers at the micron scale is of importance for these purposes, limited work has been done in developing such patterning techniques. Here, we present a simple and direct approach to pattern stacked supported lipid bilayers (SLBs using polymer stencil lift-off and the electrostatic interactions between cationic and anionic lipids. Both homogeneous and phase-segregated stacked SLB patterns were produced, demonstrating that the stacked lipid bilayers retain lateral diffusivity. We demonstrate patterned SLB stacks of up to four bilayers, where fluorescence resonance energy transfer (FRET and quenching was used to probe the interactions between lipid bilayers. Furthermore, the study of lipid phase behaviour showed that gel phase domains align between adjacent layers. The proposed stacked SLB pattern platform provides a robust model for studying lipid behaviour with a controlled number of bilayers, and an attractive means towards building functional bioinspired materials or devices.

  9. Electron-beam patterned self-assembled monolayers as templates for Cu electrodeposition and lift-off

    Directory of Open Access Journals (Sweden)

    Zhe She

    2012-02-01

    Full Text Available Self-assembled monolayers (SAMs of 4'-methylbiphenyl-4-thiol (MBP0 adsorbed on polycrystalline gold substrates served as templates to control electrochemical deposition of Cu structures from acidic solution, and enabled the subsequent lift-off of the metal structures by attachment to epoxy glue. By exploiting the negative-resist behaviour of MBP0, the SAM was patterned by means of electron-beam lithography. For high deposition contrast a two-step procedure was employed involving a nucleation phase around −0.7 V versus Cu2+/Cu and a growth phase at around −0.35 V versus Cu2+/Cu. Structures with features down to 100 nm were deposited and transferred with high fidelity. By using substrates with different surface morphologies, AFM measurements revealed that the roughness of the substrate is a crucial factor but not the only one determining the roughness of the copper surface that is exposed after lift-off.

  10. Fabrication of 45 degrees template grain boundary junctions using a CaO lift-off technique

    NARCIS (Netherlands)

    IJsselsteijn, R.P.J.; Terpstra, D.; Flokstra, J.; Rogalla, H.

    1994-01-01

    45 degrees grain boundary junctions have been made using (100) MgO substrates, a CeO2 template layer and an YBa2Cu3O7 top layer. To minimize the damage to the MgO surface, which will occur if the CeO2 is structured using ion milling, the CeO2 layer has been structured using the CaO lift-off techniqu

  11. Oxidation of Self Lift-off Silicon Microchannels%自分离硅微通道的氧化

    Institute of Scientific and Technical Information of China (English)

    田菲; 袁丁; 王连卫

    2009-01-01

    本文研究了自分离硅微通道(self lift-off silicon microchannels)的氧化问题.自分离是在特定的实验条件下,在完成电化学刻蚀后,硅微通道可以自动和衬底分离的一种新技术.研究发现,在使用传统的干氧-湿氧-干氧氧化化过程中,硅微通道出现了弯曲变形的现象.微通道越薄,其形变越大.通过使用较厚的硅微通道以及在干-湿-干氧化过程之前增加了干氧,以及先进行激光切割的步骤,改善和基本消除了弯曲变形的现象.%The oxidation of the self lift-off silicon microchannels is studied. Self lift-off silicon micro-channels are fabricated by a new technology; under certain experimental conditions, the silicon micro-channels can lift off from the substrate automatically after electrochemical etching. In the process of the traditional dry-wet-dry oxidation, damages and distortion of the silicon microchannels occurred. It was found that the thinner the silicon microchannels, the more serious the distortion and damages are. By u-sing thicker silicon microchannels and adding a procedure of dry oxidation before the dry-wet-dry oxi-dation, the damages and distortion of the silicon microchannels can be eliminated.

  12. A more general Force Balance Model to predict Bubble Departure and Lift-off Diameters in flow boiling

    Science.gov (United States)

    Kommajosyula, Ravikishore; Mazzocco, Thomas; Ambrosini, Walter; Baglietto, Emilio

    2016-11-01

    Accurate prediction of Bubble Departure and Lift-off Diameters is key for development of closures in two-phase Eulerian CFD simulation of Flow Boiling, owing to its sensitivity in the Heat Flux partitioning approach. Several models ranging from simple correlations to solving complex force balance models have been proposed in literature; however, they rely on data-fitting for specific databases, and have shown to be inapplicable for general flow applications. The aim of this study is to extend the approach by proposing a more consistent and general formulation that accounts for relevant forces acting on the Bubble at the point of Departure and Lift-off. Among the key features of the model, the Bubble Inclination angle is treated as an unknown to be inferred along with the Departure Diameter, and the relative velocity of the bubble sliding on the surface, is modeled to determine the Lift-off Diameter. A novel expression is developed for the bubble growth force in terms of flow quantities, based on extensive data analysis. The model has been validated using 6 different experimental databases with varying flow conditions and 3 fluids. Results show high accuracy of predictions over a broad range, outperforming existing models both in terms of accuracy and generality. CASL - The Consortium for Advanced Simulation of LWRs.

  13. Fabrication of nano-sized magnetic tunnel junctions using lift-off process assisted by atomic force probe tip.

    Science.gov (United States)

    Jung, Ku Youl; Min, Byoung-Chul; Ahn, Chiyui; Choi, Gyung-Min; Shin, Il-Jae; Park, Seung-Young; Rhie, Kungwon; Shin, Kyung-Ho

    2013-09-01

    We present a fabrication method for nano-scale magnetic tunnel junctions (MTJs), employing e-beam lithography and lift-off process assisted by the probe tip of atomic force microscope (AFM). It is challenging to fabricate nano-sized MTJs on small substrates because it is difficult to use chemical mechanical planarization (CMP) process. The AFM-assisted lift-off process enables us to fabricate nano-sized MTJs on small substrates (12.5 mm x 12.5 mm) without CMP process. The e-beam patterning has been done using bi-layer resist, the poly methyl methacrylate (PMMA)/ hydrogen silsesquioxane (HSQ). The PMMA/HSQ resist patterns are used for both the etch mask for ion milling and the self-aligned mask for top contact formation after passivation. The self-aligned mask buried inside a passivation oxide layer, is readily lifted-off by the force exerted by the probe tip. The nano-MTJs (160 nm x 90 nm) fabricated by this method show clear current-induced magnetization switching with a reasonable TMR and critical switching current density.

  14. Can Skateboarding Save the Planet? A Curricular Unit on Global Climate Change Developed Through the NASA LIFT-OFF Program

    Science.gov (United States)

    Pruett, L. E.; Burrell, S.; Chidester, C.; Metzger, E. P.

    2010-12-01

    The inclusion of global climate change education in California public high schools is constrained by several factors, including the planning time needed to effectively correlate state content standards to the multidisciplinary science of climate change, the lack of time in the curriculum, and budget constraints that limit resources for teachers. Recent efforts by the NASA LIFT-OFF program to support classroom teachers in the development of inquiry-based curricular materials have helped to alleviate many of these burdens. NASA LIFT-OFF is funded by a grant to the Alameda County Office of Education and involves a partnership between the Alameda, Santa Clara, and Los Angeles county offices of education and science faculty at California State University (CSU) East Bay, San Jose State University (SJSU), and Cal Poly Pomona. LIFT-OFF goals are to improve high school science teachers’ content knowledge through interactions with scientists from the CSU campuses, NASA, and the SETI Institute and to enhance their ability to plan and implement high-quality science inquiry in their classrooms. LIFT-OFF teachers at the three CSU campuses are developing instructional cases that use NASA resources and research-based pedagogical practices to explore engaging real-world questions. We participated in SJSU’s 2010 LIFT-OFF summer institute and worked as a team to develop a 12-day unit for high school students that focuses on the science behind global climate change. In addition to delivering science content, the unit engages students in critical thinking and evaluation. Students generate, access and interpret data, and use the knowledge gained to make small lifestyle changes that aid in the reduction of their greenhouse gas emissions. Not only does this unit of study empower students to make science-based decisions, it also incorporates diverse learning strategies, such as the use of visuals aids, language acquisition techniques to improve literacy, formative assessments and daily

  15. Integrated, Flexible, High-efficiency Solar Cells: Epitaxial Lift-Off GaAs Solar Cells and Enabling Substrate Reuse

    Science.gov (United States)

    2012-08-01

    welded to Kapton®. •  Lift off performed with HF . –  Etch selectivity is ~107...223503  (2009)—UM.   Epitaxial  Li>-­‐Off  (ELO) Epitaxial  ProtecLon  Layers Cold   Welding MulLple  Growths  on  Single...Cells Growth MetallizaLon Cold   Welding Epitaxial  Li>  0ff Surface  Cleaning GSMBE Thin-­‐Film  FabricaLon 5   GaAs, 0.1

  16. Effect of Impeller Geometry on Lift-Off Characteristics and Rotational Attitude in a Monopivot Centrifugal Blood Pump.

    Science.gov (United States)

    Nishida, Masahiro; Nakayama, Kento; Sakota, Daisuke; Kosaka, Ryo; Maruyama, Osamu; Kawaguchi, Yasuo; Kuwana, Katsuyuki; Yamane, Takashi

    2016-06-01

    The effect of the flow path geometry of the impeller on the lift-off and tilt of the rotational axis of the impeller against the hydrodynamic force was investigated in a centrifugal blood pump with an impeller supported by a single-contact pivot bearing. Four types of impeller were compared: the FR model with the flow path having both front and rear cutouts on the tip, the F model with the flow path having only a front cutout, the R model with only a rear cutout, and the N model with a straight flow path. First, the axial thrust and the movement about the pivot point, which was loaded on the surface of the impeller, were calculated using computational fluid dynamics (CFD) analysis. Next, the lift-off point and the tilt of the rotational axis of the impeller were measured experimentally. The CFD analysis showed that the axial thrust increased gently in the FR and R models as the flow rate increased, whereas it increased drastically in the F and N models. This difference in axial thrust was likely from the higher pressure caused by the smaller circumferential velocity in the gap between the top surface of the impeller and the casing in the FR and R models than in the F and N models, which was caused by the rear cutout. These results corresponded with the experimental results showing that the impellers lifted off in the F and N models as the flow rate increased, whereas it did not in the FR and R models. Conversely, the movement about the pivot point increased in the direction opposite the side with the pump outlet as the flow rate increased. However, the tilt of the rotational axis of the impeller, which oriented away from the pump outlet, was less than 0.8° in any model under any conditions, and was considered to negligibly affect the rotational attitude of the impeller. These results confirm that a rear cutout prevents lift-off of the impeller caused by a decrease in the axial thrust.

  17. Spectroscopic detection of exogenous materials in latent fingerprints treated with powders and lifted off with adhesive tapes.

    Science.gov (United States)

    Banas, A; Banas, K; Breese, M B H; Loke, J; Lim, S K

    2014-07-01

    Fingerprint evidence offers great value to criminal investigations since it is an internationally recognized and established means of human identification. With recent advances in modern technology, scientists have started analyzing not only the ridge patterns of fingerprints but also substances which can be found within them. The aim of this work was to determine whether Fourier transform infrared (FTIR) spectromicroscopy could be used to detect contamination in a fingerprint which was dusted with powder (a technique already recognized as an effective and reliable method for developing latent fingerprints) and subsequently lifted off with adhesive tape. Explosive materials (pentaerythritol tetranitrate, C-4, TNT) and noncontrolled substances (sugar, aspirin) were used to prepare contaminated fingerprints on various substrates. Freshly deposited fingermarks with powders which were lifted off with adhesive tapes (provided by Singapore Police Force) were analyzed using a Bruker Hyperion 2000 microscope at the ISMI beamline (Singapore Synchrotron Light Source) with an attenuated total reflection objective. FTIR spectroscopy is a nondestructive technique which requires almost no sample preparation. Further, the fingerprint under analysis remains in pristine condition, allowing subsequent analysis if necessary. All analyzed substances were successfully distinguished using their FTIR spectra in powdered and lifted fingerprints. This method has the potential to significantly impact forensic science by greatly enhancing the information that can be obtained from the study of fingerprints.

  18. Lift-Off Free Fabrication Approach for Periodic Structures with Tunable Nano Gaps for Interdigitated Electrode Arrays.

    Science.gov (United States)

    Partel, Stefan; Dincer, Can; Kasemann, Stephan; Kieninger, Jochen; Edlinger, Johannes; Urban, Gerald

    2016-01-26

    We report a simple, low-cost and lift-off free fabrication approach for periodic structures with adjustable nanometer gaps for interdigitated electrode arrays (IDAs). It combines an initial structure and two deposition process steps; first a dielectric layer is deposited, followed by a metal evaporation. The initial structure can be realized by lithography or any other structuring technique (e.g., nano imprint, hot embossing or injection molding). This method allows the fabrication of nanometer sized gaps and completely eliminates the need for a lift-off process. Different substrate materials like silicon, Pyrex or polymers can be used. The electrode gap is controlled primarily by sputter deposition of the initial structure, and thus, adjustable gaps in the nanometer range can be realized independently of the mask or stamp pattern. Electrochemical characterizations using redox cycling in ferrocenemethanol (FcMeOH) demonstrate signal amplification factors of more than 110 together with collection factors higher than 99%. Furthermore, the correlation between the gap width and the amplification factor was studied to obtain an electrochemical performance assessment of the nano gap electrodes. The results demonstrate an exponential relationship between amplification factor and gap width.

  19. Cleaved laser facets on free-standing InGaN LD membrane created by laser lift-off and structural characterisation of the membrane

    Science.gov (United States)

    Zilan, Li; Xiaodong, Hu; Zhixin, Qin; Tongjun, Yu; Ruijuan, Nie; Min, Lu; Qian, Ren; Bei, Zhang; Zhijian, Yang; Weihua, Chen; Zhizhong, Chen; Hua, Yang; Guoyi, Zhang

    2004-09-01

    Cleaved laser facets on free-standing InGaN laser diode membrane created by laser lift-off were fabricated and studied. Cleaved laser facets on GaN on sapphire have been compared with those on free-standing laser membrane. Atomic force microscopy and scanning electron microscopy results show that the cleaved laser facets on free-standing laser membrane are much smoother than those on sapphire. Transmission electron microscopy images show that no significant crystal quality degradation has been introduced during the laser lift-off process.

  20. Fabrication of a 77 GHz Rotman Lens on a High Resistivity Silicon Wafer Using Lift-Off Process

    Directory of Open Access Journals (Sweden)

    Ali Attaran

    2014-01-01

    Full Text Available Fabrication of a high resistivity silicon based microstrip Rotman lens using a lift-off process has been presented. The lens features 3 beam ports, 5 array ports, 16 dummy ports, and beam steering angles of ±10 degrees. The lens was fabricated on a 200 μm thick high resistivity silicon wafer and has a footprint area of 19.7 mm × 15.6 mm. The lens was tested as an integral part of a 77 GHz radar where a tunable X band source along with an 8 times multiplier was used as the RF source and the resulting millimeter wave signal centered at 77 GHz was radiated through a lens-antenna combination. A horn antenna with a downconverter harmonic mixer was used to receive the radiated signal and display the received signal in an Advantest R3271A spectrum analyzer. The superimposed transmit and receive signal in the spectrum analyzer showed the proper radar operation confirming the Rotman lens design.

  1. Dichromatic InGaN-based white light emitting diodes by using laser lift-off and wafer-bonding schemes

    Science.gov (United States)

    Lee, Y. J.; Lin, P. C.; Lu, T. C.; Kuo, H. C.; Wang, S. C.

    2007-04-01

    An InGaN-based dual-wavelength blue/green (470nm/550nm) light emitting diode (LED) with three terminal operations has been designed and fabricated by using sapphire laser lift-off and wafer-bonding schemes. The device is equivalent to a parallel connection of blue and green LEDs; thus the effective electrical resistance of the device could be reduced. The luminous efficiency is 40lm/W at 20mA, accompanied by a broad electroluminescence emission with a combination of blue and green colors. This monolithically integrated dichromatic lighting structure has great potential in the application of the solid-state lighting.

  2. Fabrication of metallic nanostructures of sub-20 nm with an optimized process of E-beam lithography and lift-off

    KAUST Repository

    Yue, Weisheng

    2012-01-01

    A process consisting of e-beam lithography and lift-off was optimized to fabricate metallic nanostructures. This optimized process successfully produced gold and aluminum nanostructures with features size less than 20 nm. These structures range from simple parallel lines to complex photonic structures. Optical properties of gold split ring resonators (SRRs) were characterized with Raman spectroscopy. Surface-Enhanced Raman Scattering (SERS) on SRRs was observed with 4-mercaptopyridine (4-MPy) as molecular probe and greatly enhanced Raman scattering was observed. Copyright © 2012 American Scientific Publishers.

  3. 脉冲涡流无损检测提离效应研究%Study of Lift - Off Effects for Pulsed Eddy Current Nondestructive Testing Technique

    Institute of Scientific and Technical Information of China (English)

    曹海霞; 王畅; 杨宾峰; 张军潮; 张辉

    2011-01-01

    In the course of pulsed eddy current testing, the incline of the probe or the roughness of the surface of the tested object will lead to the lift - off effects, which have a bad influence on the result of pulsed eddy current (PEC) nondestructive testing.Based on the analysis of the operating principle of PEC, two different simulation models with the excitation coils of columniform and rectangle structures are established by ANSYS finite element simulation software and the simulations on the specimen of ferromagnetic and non -ferromagnetic materials are done respectively.Through the analysis of the eddy current and rotated magnetic field, the influence effect of response signal with the variation of the lift - off distance and the reason is given.Finally, the results of simulation are verified by experiment methods.The results of the experimental work confirm the correctness of simulation, which will lay the foundation for the elimination of lift - off effects.%在脉冲涡流检测过程中,由于探头倾斜或被测对象表面不光滑会产生提离效应,提离效应严重影响着脉冲涡流无损检测的结果.本文在分析脉冲涡流检测技术工作原理的基础上,采用ANSYS有限元仿真软件建立了激励线圈为圆柱形和矩形两种结构的模型,并分别针对有裂纹缺陷的铁磁性(钢)和非铁磁性(铝)试件进行了仿真研究,通过分析试件中感应涡流和扰动磁场的变化,给出了不同情况下检测信号随提离变化的规律,并从原理上给出了解释.最后,通过实验的方法对仿真结果进行了验证,实验结果表明了仿真结果的正确性,从而为进一步的消除提离效应提供了有价值的参考依据.

  4. Lightweight, Flexible Photovoltaic Module Project

    Data.gov (United States)

    National Aeronautics and Space Administration — With recent advances in MicroLink's inverted metamorphic (IMM) multijunction epitaxial lift off (ELO) solar cells, new opportunities for solar cell packaging are...

  5. Lightweight Structures.

    Science.gov (United States)

    Shaver and Co., Michigan City, IN.

    One of the newest and most promising developments in architecture has been the use of lightweight structures for encapsulating space. Using this new technology, builders can enclose large and small areas at a fraction of the cost of conventional construction and at the same time provide interior space that is totally flexible. This brochure shows…

  6. Halo-coronal mass ejections near the 23rd solar minimum: lift-off, inner heliosphere, and in situ (1 AU signatures

    Directory of Open Access Journals (Sweden)

    D. B. Berdichevsky

    Full Text Available The extreme ultraviolet (EUV signatures of a solar lift-off, decametric and kilometric radio burst emissions and energetic particle (EP inner heliospheric signatures of an interplanetary shock, and in situ identification of its driver through solar wind observations are discussed for 12 isolated halo coronal mass ejections (H-CMEs occurring between December 1996 and 1997. For the aforementioned twelve and the one event added in the discussion, it is found that ten passed several necessary conditions for being a "Sun-Earth connection". It is found that low corona EUV and Ha chromospheric signatures indicate filament eruption as the cause of H-CME. These signatures indicate that the 12 events can be divided into two major subsets, 7 related to active regions (ARs and 5 unrelated or related to decayed AR. In the case of events related to AR, there is indication of a faster lift-off, while a more gradual lift-off appears to characterize the second set. Inner heliospheric signatures – the presence of long lasting enhanced energetic particle flux and/or kilometric type II radio bursts – of a driven shock were identified in half of the 12 events. The in situ (1 AU analyses using five different solar wind ejecta signatures and comparisons with the bidirectional flow of suprathermal particles and Forbush decreases result in indications of a strong solar wind ejecta signatures for 11 out of 12 cases. From the discussion of these results, combined with work by other authors for overlapping events, we conclude that good Sun-Earth connection candidates originate most likely from solar filament eruptions with at least one of its extremities located closer to the central meridian than ~ 30° E or ~ 35° W with a larger extension in latitudinal location possible. In seven of the twelve cases it appears that the encountered ejecta was driving a shock at 1 AU. Support for this interpretation is found on the approximately equal

  7. Lift-off of mesoporous layers by electrochemical etching on Si (100) substrates with miscut of 6{sup o} off towards (111)

    Energy Technology Data Exchange (ETDEWEB)

    Garralaga Rojas, E., E-mail: garralaga@isfh.de [Institut fuer Solarenergieforschung Hameln, Am Ohrberg 1, 31860 Emmerthal (Germany); Terheiden, B.; Plagwitz, H.; Hensen, J. [Institut fuer Solarenergieforschung Hameln, Am Ohrberg 1, 31860 Emmerthal (Germany); Wiedemeier, V.; Berth, G.; Zrenner, A. [Centre for Optoelectronics and Photonics Paderborn, University of Paderborn, Warburger Str. 100, 33098 Paderborn (Germany); Brendel, R. [Institut fuer Solarenergieforschung Hameln, Am Ohrberg 1, 31860 Emmerthal (Germany)

    2011-10-31

    Uniform mesoporous Si double layers are formed on 4 inch p-type < 100> wafers with an off orientation of 6{sup o} towards < 111> by means of electrochemical etching in ethanoic-based HF electrolytes. These substrates are of interest for the epitaxial growth of III-V compound semiconductor stacks on their top for the production of multi-junction solar cells and very thin electronic devices. We demonstrate transfer of porous layers after an annealing process in hydrogen atmosphere. Electron Back-Scatter Diffraction analysis confirms that the substrate orientation is conserved during the etching and annealing steps. Confocal {mu}-Raman spectroscopy analysis shows a decrease in the Raman signal intensity after etching and a subsequent increase after annealing while no shift is observed. By means of Atomic Force Microscopy, analysis the surface appearance after the etching and annealing steps can be visualized. The mean surface roughness varies during the process from 0.55 nm for the unprocessed wafers to 0.27 nm after etching and 0.78 nm after annealing. The decrease of average roughness after etching is caused by an electropolishing step prior to porous formation. Despite of slight increase of mean surface roughness after annealing the samples are still appropriate for high quality epitaxial growth and subsequent lift-off.

  8. Theoretical modeling of CHF for near-saturated pool boiling and flow boiling from short heaters using the interfacial lift-off criterion

    Energy Technology Data Exchange (ETDEWEB)

    Mudawar, I.; Galloway, J.E.; Gersey, C.O. [Purdue Univ., West Lafayette, IN (United States)] [and others

    1995-12-31

    Pool boiling and flow boiling were examined for near-saturated bulk conditions in order to determine the critical heat flux (CHF) trigger mechanism for each. Photographic studies of the wall region revealed features common to both situations. At fluxes below CHF, the vapor coalesces into a wavy layer which permits wetting only in wetting fronts, the portions of the liquid-vapor interface which contact the wall as a result of the interfacial waviness. Close examination of the interfacial features revealed the waves are generated from the lower edge of the heater in pool boiling and the heater`s upstream region in flow boiling. Wavelengths follow predictions based upon the Kelvin-Helmholtz instability criterion. Critical heat flux in both cases occurs when the pressure force exerted upon the interface due to interfacial curvature, which tends to preserve interfacial contact with the wall prior to CHF, is overcome by the momentum of vapor at the site of the first wetting front, causing the interface to lift away from the wall. It is shown this interfacial lift-off criterion facilitates accurate theoretical modeling of CHF in pool boiling and in flow boiling in both straight and curved channels.

  9. 基于系统辨识的脉冲涡流信号提离效应%Lift-off Effect of Pulsed Eddy Current Signal Based on System Identification

    Institute of Scientific and Technical Information of China (English)

    顾增涛; 付跃文; 薛盛龙

    2015-01-01

    Defect signal in pulsed eddy current testing (PEC)will be severely disturbed by lift-off effect.This paper adopts system identification method of ARX model to analyze lift-off effect.By using the signal tested by sensors in the air as input signal and the signal tested at different lift-off heights as output signal,the least-square method was used to estimate the parameter of the model in order to obtain ARX model with different parameters. The result of the model shows the frequency characteristics of systematic models can be used to indicate different lift-off height of defects in deeper position inside the specimens during the test.%脉冲涡流检测中缺陷信号会受到提离效应的严重干扰。采用带控制量的自回归(ARX)模型的系统辨识方法分析提离效应。首先,利用传感器处于空气中测得的信号作为输入信号,分别以不同提离高度测得的信号作为输出信号,然后利用最小二乘法对模型的参数估计后得到不同参数的ARX模型。结果表明,系统模型的高频特性可在检测时用来指示试件内部较深缺陷的不同提离高度。

  10. Photoresist-free patterning by mechanical abrasion of water-soluble lift-off resists and bare substrates: toward green fabrication of transparent electrodes.

    Science.gov (United States)

    Printz, Adam D; Chan, Esther; Liong, Celine; Martinez, René S; Lipomi, Darren J

    2013-01-01

    This paper describes the fabrication of transparent electrodes based on grids of copper microwires using a non-photolithographic process. The process--"abrasion lithography"--takes two forms. In the first implementation (Method I), a water-soluble commodity polymer film is abraded with a sharp tool, coated with a conductive film, and developed by immersion in water. Water dissolves the polymer film and lifts off the conductive film in the unabraded areas. In the second implementation (Method II), the substrate is abraded directly by scratching with a sharp tool (i.e., no polymer film necessary). The abraded regions of the substrate are recessed and roughened. Following deposition of a conductive film, the lower profile and roughened topography in the abraded regions prevents mechanical exfoliation of the conductive film using adhesive tape, and thus the conductive film remains only where the substrate is scratched. As an application, conductive grids exhibit average sheet resistances of 17 Ω sq(-1) and transparencies of 86% are fabricated and used as the anode in organic photovoltaic cells in concert with the conductive polymer, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS). Compared to devices in which PEDOT:PSS alone serves as an anode, devices comprising grids of copper/nickel microwires and PEDOT:PSS exhibit lowered series resistance, which manifests in greater fill factor and power conversion efficiency. This simple method of forming micropatterns could find use in applications where cost and environmental impact should be minimized, especially as a potential replacement for the transparent electrode indium tin oxide (ITO) in thin-film electronics over large areas (i.e., solar cells) or as a method of rapid prototyping for laboratory-scale devices.

  11. Photoresist-free patterning by mechanical abrasion of water-soluble lift-off resists and bare substrates: toward green fabrication of transparent electrodes.

    Directory of Open Access Journals (Sweden)

    Adam D Printz

    Full Text Available This paper describes the fabrication of transparent electrodes based on grids of copper microwires using a non-photolithographic process. The process--"abrasion lithography"--takes two forms. In the first implementation (Method I, a water-soluble commodity polymer film is abraded with a sharp tool, coated with a conductive film, and developed by immersion in water. Water dissolves the polymer film and lifts off the conductive film in the unabraded areas. In the second implementation (Method II, the substrate is abraded directly by scratching with a sharp tool (i.e., no polymer film necessary. The abraded regions of the substrate are recessed and roughened. Following deposition of a conductive film, the lower profile and roughened topography in the abraded regions prevents mechanical exfoliation of the conductive film using adhesive tape, and thus the conductive film remains only where the substrate is scratched. As an application, conductive grids exhibit average sheet resistances of 17 Ω sq(-1 and transparencies of 86% are fabricated and used as the anode in organic photovoltaic cells in concert with the conductive polymer, poly(3,4-ethylenedioxythiophene:poly(styrenesulfonate (PEDOT:PSS. Compared to devices in which PEDOT:PSS alone serves as an anode, devices comprising grids of copper/nickel microwires and PEDOT:PSS exhibit lowered series resistance, which manifests in greater fill factor and power conversion efficiency. This simple method of forming micropatterns could find use in applications where cost and environmental impact should be minimized, especially as a potential replacement for the transparent electrode indium tin oxide (ITO in thin-film electronics over large areas (i.e., solar cells or as a method of rapid prototyping for laboratory-scale devices.

  12. Influence of laser lift-off on optical and structural properties of InGaN/GaN vertical blue light emitting diodes

    Directory of Open Access Journals (Sweden)

    M. H. Doan

    2012-06-01

    Full Text Available The influences of the laser lift-off (LLO process on the InGaN/GaN blue light emitting diode (LED structures, grown on sapphire substrates by low-pressure metalorganic chemical vapor deposition, have been comprehensively investigated. The vertical LED structures on Cu carriers are fabricated using electroplating, LLO, and inductively coupled plasma etching processes sequentially. A detailed study is performed on the variation of defect concentration and optical properties, before and after the LLO process, employing high-resolution transmission electron microscopy (HRTEM, scanning electron microscopy (SEM observations, cathodoluminescence (CL, photoluminescence (PL, and high-resolution X-ray diffraction (HRXRD measurements. The SEM observations on the distribution of dislocations after the LLO show well that even the GaN layer near to the multiple quantum wells (MQWs is damaged. The CL measurements reveal that the peak energy of the InGaN/GaN MQW emission exhibits a blue-shift after the LLO process in addition to a reduced intensity. These behaviors are attributed to a diffusion of indium through the defects created by the LLO and creation of non-radiative recombination centers. The observed phenomena thus suggest that the MQWs, the active region of the InGaN/GaN light emitting diodes, may be damaged by the LLO process when thickness of the GaN layer below the MQW is made to be 5 μm, a conventional thickness. The CL images on the boundary between the KrF irradiated and non-irradiated regions suggest that the propagation of the KrF laser beam and an accompanied recombination enhanced defect reaction, rather than the propagation of a thermal shock wave, are the main origin of the damage effects of the LLO process on the InGaN/GaN MQWs and the n-GaN layer as well.

  13. Area-Selective Lift-Off Mechanism Based on Dual-Triggered Interfacial Adhesion Switching: Highly Facile Fabrication of Flexible Nano-Mesh Electrode.

    Science.gov (United States)

    Yu, Seunghee; Han, Hyeuk Jin; Kim, Jong Min; Yim, Soonmin; Sim, Dong Min; Lim, Hunhee; Lee, Jung Hye; Park, Woon Ik; Park, Jae Hong; Kim, Kwang Ho; Jung, Yeon Sik

    2017-02-28

    With the recent emergence of flexible and wearable optoelectronic devices, the achievement of sufficient bendability and stretchability of transparent and conducting electrodes (TCEs) has become an important requirement. Although metal-mesh-based structures have been investigated for TCEs because of their excellent performances, the fabrication of mesh or grid structures with a sub-micron line width is still complex due to the requirements of laborious lithography and pattern transfer steps. Here, we introduce an extremely facile fabrication technique for metal patterns embedded in a flexible substrate based on sub-micron replication and an area-selective delamination (ASD) patterning. The high-yield, area-specific lift-off process is based on the principle of solvent-assisted delamination of deposited metal thin films and a mechanical triggering effect by soft wiping or ultrasonication. Our fabrication process is highly simple, convenient, and cost-effective in that it does not require any lithography/etching steps or sophisticated facilities. Moreover, their outstanding optical and electrical properties (e.g. sheet resistances of 0.43 Ω sq(-1) at 94% transmittance), which are markedly superior to those of other flexible TCEs, are demonstrated. Furthermore, there is no significant change of resistance during over 1,000 repeated bending cycles with a bending radius of 5 mm and for immersing in various solvents such as salt water and organic solvents. Finally, we demonstrate high-performance transparent heaters and flexible touch panels using the fabricated nanomesh electrode, confirming the long-range electrical conduction and reliability of the electrode.

  14. Freestanding single crystal chemical vapor deposited diamond films produced using a lift-off method: Response to {alpha}-particles from {sup 241}Am and crystallinity

    Energy Technology Data Exchange (ETDEWEB)

    Tsubouchi, Nobuteru, E-mail: nobu-tsubouchi@aist.go.jp [Diamond Research Laboratory, National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577 (Japan); Mokuno, Y. [Diamond Research Laboratory, National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577 (Japan); Kakimoto, A.; Fujita, F.; Kaneko, J.H. [Graduate School of Engineering, Hokkaido University, Sapporo 060-8628 (Japan); Yamada, H.; Chayahara, A.; Shikata, S. [Diamond Research Laboratory, National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577 (Japan)

    2012-09-01

    Thick ({approx}100 {mu}m) undoped diamond films were grown homoepitaxially on single crystal (SC) diamond substrates by microwave plasma chemical vapor deposition (CVD). To form a freestanding SC diamond film (plate), the substrate was pre-ion-implanted with high-energy ion beams before the film growth, and after the thick-film deposition, the substrate was eliminated using a lift-off method, resulting in fabrication of a SC CVD diamond plate. Two samples were prepared; sample 1 was grown on a (0 0 1) oriented, nitrogen doped CVD SC diamond at {approx}900 Degree-Sign C with the input microwave power of 1.7 kW, while sample 2 was grown on a (0 0 1) oriented, high-pressure high-temperature synthesized type-Ib SC diamond at {approx}900 Degree-Sign C with the input microwave power of 1.25 kW. The formed SC plates have high optical transparencies, indicating no remarkable optical absorptions seen in the wavelength from ultraviolet to near infrared. The photoluminescence (PL) spectra of both samples show strong free exciton FE peaks, while in sample 2 relatively strong optical emissions corresponding to nitrogen related centers were observed in the visible region. After the metal electrodes were formed on both faces of the SC diamond plate to fabricate a sandwich-type diamond particle detector, the energy spectra of 5.486 MeV {alpha}-particles from {sup 241}Am were measured. The charge collection efficiencies (CCEs) of sample 1 were CCE = 98% for a hole transport and CCE = 89% for an electron transport, respectively, while CCEs of sample 2 were CCE = 80% for a hole transport and CCE = 78% for an electron transport, respectively. These results indicate that both holes and electrons in sample 2 were trapped much more than those in sample 1. Possible candidates of carrier capture centers are nitrogen and/or nitrogen-vacancy centers observed in PL, nonradiative defect (complex) centers, extended defects such as threading dislocations observed in micrographs taken with

  15. Sub-Half Micrometer Gate Lift-Off By Three Layer Resist Process Via Electron Beam Lithography For Gallium Arsenide Monolithic Microwave Integrated Circuits (MIMICs)

    Science.gov (United States)

    Nagarajan, Rao M.; Rask, Steven D.; King, Michael R.; Yard, Thomas K.

    1988-06-01

    A three layer resist process for gate lift-oft on Gallium Arsenide MIMICs by electron Dean and optical lithographies are described. The electron beam lithography process consists of Poly (Dimethyl Glutarimide) PMGI as tne planarizing layer, a Plasma Enhanced Chemical Vapour Deposition silicon nitride (SiN) as an intermediate barrier layer and Poly (Methyl methacrylate), PMMA, as the top imaging layer. The PivimA is exposed by Cambridge Electron beam system EBMF 6.4 at 20kev and developed in Methyl Ethyl Ketone/Iso Propyl Alcohol. The pattern is then transferred to the SiN layer by cF4/o2 plasma etcning. The SiN layer is then used as the mask to transfer the pattern to the PMGI layer by 02 kteactive Ion Etching until tne GaAS is exposed. The various processing parameters are optimized to obtain lip or overnang suitable for lift-off with 0.20μm gate dimension. After the GaAS has been recessed (to reduce the parasitic source resistance), a thick 9000Å Ti/Pt/Au gate metal is evaporated and the unwanted gate metal is lifted oft using PMGI stripper. To use the three layer resist process in optical litnograpny, the MG.'. planarizing layer and PECVD SiN layer is used along with optical pnotoresist AZ1450J as a top imaging layer. inc sofcbake, uV exposure dose (436 nm) and development time for AZ145UJ are optimized to obtain 0.5μm to 1.0μm gate dimensions. The etch parameters for the pattern transfer to SiN and tnen to PMGI layers are same as in tne above process. The process levels such as mesa, source/drain, contact and metal levels for GaAs mlivilt,s are defined by UV lithography (Karl Suss contact aligner) using single layer pnotoresist. A nign overlay accuracy is obtained by use of gold metal Dumps as registration marks for aligning tne electron Dean exposed gate to optically exposed source/drain channel. Thus a higher tnrougnput and better linewidtn control are obtained using electron beam/optical lithography tecnniques. This approach is currently used to

  16. On the automobile lightweight

    Institute of Scientific and Technical Information of China (English)

    Ma Mingtu; Yi Hongliang; Lu Hongzhou; Wan Xinming

    2012-01-01

    The significance, description parameters, evaluation method, implement way and design for lightweight of au- tomobile are comprehensively reviewed. The relationship among the performances of auto parts & components, the prop- erties of materials and application of advanced technologies is also elaborated. According to recently related progress of lightweight and authors' research and developing work, lightweight of automobile is comprehensively and systematically overviewed.

  17. High-Pressure Lightweight Thrusters

    Science.gov (United States)

    Holmes, Richard; McKechnie, Timothy; Shchetkovskiy, Anatoliy; Smirnov, Alexander

    2013-01-01

    Returning samples of Martian soil and rock to Earth is of great interest to scientists. There were numerous studies to evaluate Mars Sample Return (MSR) mission architectures, technology needs, development plans, and requirements. The largest propulsion risk element of the MSR mission is the Mars Ascent Vehicle (MAV). Along with the baseline solid-propellant vehicle, liquid propellants have been considered. Similar requirements apply to other lander ascent engines and reaction control systems. The performance of current state-ofthe- art liquid propellant engines can be significantly improved by increasing both combustion temperature and pressure. Pump-fed propulsion is suggested for a single-stage bipropellant MAV. Achieving a 90-percent stage propellant fraction is thought to be possible on a 100-kg scale, including sufficient thrust for lifting off Mars. To increase the performance of storable bipropellant rocket engines, a high-pressure, lightweight combustion chamber was designed. Iridium liner electrodeposition was investigated on complex-shaped thrust chamber mandrels. Dense, uniform iridium liners were produced on chamber and cylindrical mandrels. Carbon/carbon composite (C/C) structures were braided over iridium-lined mandrels and densified by chemical vapor infiltration. Niobium deposition was evaluated for forming a metallic attachment flange on the carbon/ carbon structure. The new thrust chamber was designed to exceed state-of-the-art performance, and was manufactured with an 83-percent weight savings. High-performance C/Cs possess a unique set of properties that make them desirable materials for high-temperature structures used in rocket propulsion components, hypersonic vehicles, and aircraft brakes. In particular, more attention is focused on 3D braided C/Cs due to their mesh-work structure. Research on the properties of C/Cs has shown that the strength of composites is strongly affected by the fiber-matrix interfacial bonding, and that weakening

  18. ULTRA-LIGHTWEIGHT CEMENT

    Energy Technology Data Exchange (ETDEWEB)

    Fred Sabins

    2002-07-30

    The objective of this project is to develop an improved ultra-lightweight cement using ultra-lightweight hollow glass spheres (ULHS). This report includes results from laboratory testing of ULHS systems along with other lightweight cement systems, including foamed and sodium silicate slurries. During this project quarter, a comparison study of the three cement systems examined the effect that cement drillout has on the three cement systems. Testing to determine the effect of pressure cycling on the shear bond properties of the cement systems was also conducted. This report discusses testing that was performed to analyze the alkali-silica reactivity of ULHS in cement slurries.

  19. Lightweight Robotic Excavation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Robust, lightweight, power-efficient excavation robots are mission enablers for lunar outposts and surface systems. Lunar excavators of this type cost-effectively...

  20. Lightweight Robotic Excavation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Lightweight robotic excavators address the need for machines that dig, collect, transport and dump lunar soil. Robust and productive small robots enable mining rich...

  1. Lightweight Metal Mirrors

    Science.gov (United States)

    Gossett, E.; Winslow, P.

    1984-01-01

    Two "eggcrate" halves brazed together. Lightweight flat mirrors fabricated by machining pockets in two plates of beryllium and brazing machined halves together. Mirror less than half weight of same mirror made by previous design.

  2. Manufacturing of Lightweight Mirror

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Fabrication of the lightweight mirror is one of the key techniques for many large optical systems. CAD,CAM and CNC technologies are adopted in designing and manufacturing such mirrors in CIOMP. Better working efficiency and higher lightweight grade have been achieved. The results show that mirrors up to 70% weight reduction and 0.02λ(rms.) surface accuracy or better can be obtained.

  3. ULTRA-LIGHTWEIGHT CEMENT

    Energy Technology Data Exchange (ETDEWEB)

    Fred Sabins

    2001-10-23

    The objective of this project is to develop an improved ultra-lightweight cement using ultra-lightweight hollow glass spheres (ULHS). Work reported herein addresses tasks performed in the fourth quarter as well as the other three quarters of the past year. The subjects that were covered in previous reports and that are also discussed in this report include: Analysis of field laboratory data of active cement applications from three oil-well service companies; Preliminary findings from a literature review focusing on problems associated with ultra-lightweight cements; Summary of pertinent information from Russian ultra-lightweight cement literature review; and Comparison of compressive strengths of ULHS systems using ultrasonic and crush methods Results reported from the fourth quarter include laboratory testing of ULHS systems along with other lightweight cement systems--foamed and sodium silicate slurries. These comparison studies were completed for two different densities (10.0 and 11.5 lb/gal) and three different field application scenarios. Additional testing included the mechanical properties of ULHS systems and other lightweight systems. Studies were also performed to examine the effect that circulation by centrifugal pump during mixing has on breakage of ULHS.

  4. ULTRA-LIGHTWEIGHT CEMENT

    Energy Technology Data Exchange (ETDEWEB)

    Fred Sabins

    2001-04-15

    The objective of this project is to develop an improved ultra-lightweight cement using ultralight hollow glass spheres (ULHS). Work reported herein addresses Task 1: Assess Ultra-Lightweight Cementing Problems and Task 3: Test Ultra-Lightweight Cements. Results reported this quarter include a review and summary of Halliburton Energy Services (HES) and BJ Services historical performance data for lightweight cement applications. These data are analyzed and compared to ULHS cement and foamed cement performances. Similar data is expected from Schlumberger, and an analysis of this data will be completed in the following phases of the project. Quality control testing of materials used to formulate ULHS cements in the laboratory was completed to establish baseline material performance standards. A testing protocol was developed employing standard procedures as well as procedures tailored to evaluate ULHS and foamed cement. This protocol is presented and discussed. Results of further testing of ULHS cements are presented along with an analysis to establish cement performance design criteria to be used during the remainder of the project. Finally, a list of relevant literature on lightweight cement performance is compiled for review during the next quarter.

  5. ULTRA-LIGHTWEIGHT CEMENT

    Energy Technology Data Exchange (ETDEWEB)

    Fred Sabins

    2002-01-23

    The objective of this project is to develop an improved ultra-lightweight cement using ultra-lightweight hollow glass spheres (ULHS). This report includes results from laboratory testing of ULHS systems along with other lightweight cement systems: foamed and sodium silicate slurries. Comparison studies of the three cement systems examined several properties: tensile strength, Young's modulus, water permeability, and shear bond. Testing was also done to determine the effect that temperature cycling has on the shear bond properties of the cement systems. In addition, analysis was carried out to examine alkali silica reactivity of slurries containing ULHS. Data is also presented from a study investigating the effects of mixing and pump circulation on breakage of ULHS. Information is also presented about the field application of ULHS in cementing a 7-in. intermediate casing in south Texas.

  6. MICROPATTERNING OF GOLD SUBSTRATES BASED ON POLY(PROPYLENE SULFIDE-BL-ETHYLENE GLYCOL), (PPS-PEG) BACKGROUND PASSIVATION AND THE MOLECULAR-ASSEMBLY PATTERNING BY LIFT-OFF (MAPL) TECHNIQUE.

    Science.gov (United States)

    Feller, L; Bearinger, J P; Wu, L; Hubbell, J A; Textor, M; Tosatti, S

    2008-07-01

    Poly(propylene sulfide-bl-ethylene glycol (PPS-PEG) is an amphiphilic block copolymer that spontaneously adsorbs onto gold from solution. This results in the formation of a stable polymeric layer that renders the surface protein resistant when an appropriate architecture is chosen. The established molecular assembly patterning by lift-off (MAPL) technique can convert a prestructured resist film into a pattern of biointeractive chemistry and a noninteractive background. Employing the MAPL technique, we produced a micron-scale PPS-PEG pattern on a gold substrate, and then characterized the patterned structure with Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS) and Atomic Force Microscopy (AFM). Subsequent exposure of the PPS-PEG/gold pattern to protein adsorption (full human serum) was monitored in situ; SPR-imaging (i-SPR) shows a selective adsorption of proteins on gold, but not on PPS-PEG areas. Analysis shows a reduction of serum adsorption up to 93% on the PPS-PEG areas as compared to gold, in good agreement with previous analysis of homogenously adsorbed PPS-PEG on gold. MAPL patterning of PPS-PEG block copolymers is straightforward, versatile and reproducible, and may be incorporated into biosensor-based surface analysis methods.

  7. MICROPATTERNING OF GOLD SUBSTRATES BASED ON POLY(PROPYLENE SULFIDE-BL-ETHYLENE GLYCOL), (PPS-PEG) BACKGROUND PASSIVATION AND THE MOLECULAR-ASSEMBLY PATTERNING BY LIFT-OFF (MAPL) TECHNIQUE

    Energy Technology Data Exchange (ETDEWEB)

    Feller, L; Bearinger, J P; Wu, L; Hubbell, J A; Textor, M; Tosatti, S

    2007-11-13

    Poly(propylene sulfide-bl-ethylene glycol) (PPS-PEG) is an amphiphilic block copolymer that spontaneously adsorbs onto gold from solution. This results in the formation of a stable polymeric layer that renders the surface protein resistant when an appropriate architecture is chosen. The established molecular assembly patterning by lift-off (MAPL) technique can convert a prestructured resist film into a pattern of biointeractive chemistry and a noninteractive background. Employing the MAPL technique, we produced a micron-scale PPS-PEG pattern on a gold substrate, and then characterized the patterned structure with Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS) and Atomic Force Microscopy (AFM). Subsequent exposure of the PPS-PEG/gold pattern to protein adsorption (full human serum) was monitored in situ; SPR-imaging shows a selective adsorption of proteins on gold, but not on PPS-PEG areas. Analysis shows a reduction of serum adsorption up to 93% on the PPS-PEG areas as compared to gold, in good agreement with previous analysis on homogeneously adsorbed PPS-PEG on gold. MAPL patterning of PPS-PEG block copolymers fast, versatile and reproducible, and allows for subsequent use of biosensor-based surface analysis methods.

  8. Lightweight Composite Intertank Structure

    Science.gov (United States)

    Mehle, Greg V.

    1995-01-01

    Report presents results of study for proposed lightweight composite material alternative to present semimonocoque aluminum intertank structure for advanced launch vehicles. Proposed structure integrated assembly of sandwich panels made of laminated epoxy-matrix/carbon-fiber skins, and aluminum honeycomb core.

  9. Lightweight Electric Power Cable.

    Science.gov (United States)

    1982-09-01

    8I~ .4 111 162 MICROCi Pi RL’ LUHION TESI CHARI "LIGHTWEIGHT ELECTRIC POWER CABLE" FINAL TECHNICAL REPORT SEPTEMBER 30, 1981 to SEPTEMBER 30, 1982... Vulcanized by heat to crosslink. TPE (Thermoplastic Elastomer) - Polymers having elastomeric proper- ties. Used as thermoplastics - melt formed by

  10. Lightweight incremental application upgrade

    NARCIS (Netherlands)

    T. van der Storm (Tijs)

    2006-01-01

    textabstractI present a lightweight approach to incremental application upgrade in the context of component-based software development. The approach can be used to efficiently implement an automated update feature in a platform and programming language agnostic way. A formal release model is present

  11. Thin, Lightweight Solar Cell

    Science.gov (United States)

    Brandhorst, Henry W., Jr.; Weinberg, Irving

    1991-01-01

    Improved design for thin, lightweight solar photovoltaic cells with front contacts reduces degradation of electrical output under exposure to energetic charged particles (protons and electrons). Increases ability of cells to maintain structural integrity under exposure to ultraviolet radiation by eliminating ultraviolet-degradable adhesives used to retain cover glasses. Interdigitated front contacts and front junctions formed on semiconductor substrate. Mating contacts formed on back surface of cover glass. Cover glass and substrate electrostatically bonded together.

  12. Lightweight bipolar storage battery

    Science.gov (United States)

    Rowlette, John J. (Inventor)

    1992-01-01

    An apparatus [10] is disclosed for a lightweight bipolar battery of the end-plate cell stack design. Current flow through a bipolar cell stack [12] is collected by a pair of copper end-plates [16a,16b] and transferred edgewise out of the battery by a pair of lightweight, low resistance copper terminals [28a,28b]. The copper terminals parallel the surface of a corresponding copper end-plate [16a,16b] to maximize battery throughput. The bipolar cell stack [12], copper end-plates [16a,16b] and copper terminals [28a,28b] are rigidly sandwiched between a pair of nonconductive rigid end-plates [20] having a lightweight fiber honeycomb core which eliminates distortion of individual plates within the bipolar cell stack due to internal pressures. Insulating foam [30] is injected into the fiber honeycomb core to reduce heat transfer into and out of the bipolar cell stack and to maintain uniform cell performance. A sealed battery enclosure [ 22] exposes a pair of terminal ends [26a,26b] for connection with an external circuit.

  13. Lightweight enterprise architectures

    CERN Document Server

    Theuerkorn, Fenix

    2004-01-01

    STATE OF ARCHITECTUREArchitectural ChaosRelation of Technology and Architecture The Many Faces of Architecture The Scope of Enterprise Architecture The Need for Enterprise ArchitectureThe History of Architecture The Current Environment Standardization Barriers The Need for Lightweight Architecture in the EnterpriseThe Cost of TechnologyThe Benefits of Enterprise Architecture The Domains of Architecture The Gap between Business and ITWhere Does LEA Fit? LEA's FrameworkFrameworks, Methodologies, and Approaches The Framework of LEATypes of Methodologies Types of ApproachesActual System Environmen

  14. LIGHTWEIGHT CONCRETE BASED GRANSHLAK

    Directory of Open Access Journals (Sweden)

    NETESA M. I.

    2016-02-01

    Full Text Available Raising of problem. Concrete advisable to obtain a low strength with local secondary resources for recycling and reduce the environmental burden on the environment. But it is important to design such concrete compositions with a reduced flow of cement. It is known that the coefficient of efficiency of use of cement in the concrete of the heavy and B10 is less than about 0.5, which is almost two times smaller than in class B15 concrete and above. Even lower coefficient of efficiency in light concrete cement low strength. Therefore, it is important to find patterns determining the composition of lightweight concrete based on local-products industry with more efficient use of cement in them. Purpose.. Based on the analysis of earlier research results, including with the use of methods of mathematical planning of experiments to determine the concrete contents, which can provide the requirements for the underlying layers of the floor, the compressive strength of which should correspond to the class B5. It is important to provide the required strength at minimum flow of the cement, which is the most expensive and energy-intensive part of concrete. Conclusion. Analysis of the test results of control samples of concrete in 28-day-old, the following laws. The required tensile strength of concrete compressive strength of 7.0 MPa can be obtained in the test range when used in formulations as a filler as the Dnieper hydroelectric power station fly ash and tailings Krivoy Rog iron ore YuGOK. To ensure providing the required characteristic strength of the concrete in the underlying layers of the floor is advisable to use a nominal composition per cubic meter of concrete: cement 160 kg granshlaka Plant named after Petrovsky, 675 kg of fly ash Dnieper HPP 390 kg, 400 kg of sand, 230 liters of water. Thus, while ensuring rational grain composition components can obtain the desired strength lightweight concrete based granshlaka plant Petrovsky, using as fillers

  15. Lightweight flywheel containment

    Science.gov (United States)

    Smith, James R.

    2004-06-29

    A lightweight flywheel containment composed of a combination of layers of various material which absorb the energy of a flywheel structural failure. The various layers of material act as a vacuum barrier, momentum spreader, energy absorber, and reaction plate. The flywheel containment structure has been experimentally demonstrated to contain carbon fiber fragments with a velocity of 1,000 m/s and has an aerial density of less than 6.5 g/square centimeters. The flywheel containment, may for example, be composed of an inner high toughness structural layer, and energy absorbing layer, and an outer support layer. Optionally, a layer of impedance matching material may be utilized intermediate the flywheel rotor and the inner high toughness layer.

  16. Lightweight Trauma Module - LTM

    Science.gov (United States)

    Hatfield, Thomas

    2008-01-01

    Current patient movement items (PMI) supporting the military's Critical Care Air Transport Team (CCATT) mission as well as the Crew Health Care System for space (CHeCS) have significant limitations: size, weight, battery duration, and dated clinical technology. The LTM is a small, 20 lb., system integrating diagnostic and therapeutic clinical capabilities along with onboard data management, communication services and automated care algorithms to meet new Aeromedical Evacuation requirements. The Lightweight Trauma Module is an Impact Instrumentation, Inc. project with strong Industry, DoD, NASA, and Academia partnerships aimed at developing the next generation of smart and rugged critical care tools for hazardous environments ranging from the battlefield to space exploration. The LTM is a combination ventilator/critical care monitor/therapeutic system with integrated automatic control systems. Additional capabilities are provided with small external modules.

  17. Lightweight In-Plane Actuated Deformable Mirrors for Space Telescopes

    Science.gov (United States)

    2006-09-01

    a reflective surface, such as a deformable mirror. The Michelson Interferometer, as described by Hecht [63], uses a beam splitter to divide a laser...Columbia University [90, pp. 281-290]. During the period of the lectures, the “ monolithic crys- tal filter” was discovered independently by researchers in...through a monolithic lenslet module (MLM) that focuses the light onto an RS-170v monochrome Shack-Hartmann wavefront sensor. The fidelity of the data

  18. Conditions d'apparition et formes de rebond d'un outil de forage tricône Conditions of Appearance and Forms of Lift-Off Dynamics (Bit Bouncing for a Roller Cone Drill Bit

    Directory of Open Access Journals (Sweden)

    Putot C.

    2006-12-01

    caractéristique de cohésion de la roche. Ainsi, et conformément à l'intuition, le rebond se manifestera préférentiellement avec une roche très résistante et une structure souple pour la fréquence envisagée. Des considérations d'efficacité de coupe, liées à la compatibilité plus ou moins grande de la géométrie du cône et de la courbure de l'interface du motif trilobé, sont dégagées et cadrent parfaitement avec une dissymétrie observée sur les enregistrements (Trafor du couple entre maxima et minima ; les phases de décollement et de reprise de contact en cas de rebond sont également compatibles avec les extrema de poids sur outil. The longitudinal vibration mode of the drill string can, in certain drilling conditions, degenerate into bit-bouncing wih periodic separation at the roller bit cone, rock interface; it goes without saying that this behavior must be avoided. In the presence of compact rocks, we are used to associating the lift-off dynamics to the presence of a pattern at the rock-bit interface, known as a bottom hole pattern because of its ternary symmetry. It emerges by a more or less sinusoidal, periodic undulation of the cutting edge. On soft rocks , the speed of the longitudinal vibration phenomenon is more chaotic and is the subject of specific investigations relating dynamics and the expulsion of fragments (Cutclean programme. On hardrocks, the experience proves that the pattern is repeated on each passage of the bit by differentiated erosion of the undulations, without there necessarily being detachment. A general rotation of the interface pattern then occurs, in the order of a few degrees per turn, related the phase shift between cutting effort and undulation. The bounce phenomenon appears especially when there is agreement between the running frequency of the cones --dependent on the rotational speed- and a frequency which is unique to the drilling system. However the phenomenon can also appear a long way from the resonance

  19. Lightweight Inflatable Cryogenic Tank Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal describes the development of an inflatable and lightweight polymer-fabric structured pressure vessel designed for the containment of cryogenic fluids....

  20. High Efficency Lightweight Radiators Project

    Data.gov (United States)

    National Aeronautics and Space Administration — XC Associates proposes to build on prior work to develop and characterize a very high efficiency, lightweight radiator constructed from high thermal conductivity...

  1. Lightweight hydride storage materials

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, G.J.; Guthrie, S.E.; Bauer, W. [Sandia National Labs., Livermore, CA (United States)

    1995-09-01

    The need for lightweight hydrides in vehicular applications has prompted considerable research into the use of magnesium and its alloys. Although this earlier work has provided some improved performance in operating temperature and pressure, substantial improvements are needed before these materials will significantly enhance the performance of an engineered system on a vehicle. We are extending the work of previous investigators on Mg alloys to reduce the operating temperature and hydride heat of formation in light weight materials. Two important results will be discussed in this paper: (1) a promising new alloy hydride was found which has better pressure-temperature characteristics than any previous Mg alloy and, (2) a new fabrication process for existing Mg alloys was developed and demonstrated. The new alloy hydride is composed of magnesium, aluminum and nickel. It has an equilibrium hydrogen overpressure of 1.3 atm. at 200{degrees}C and a storage capacity between 3 and 4 wt.% hydrogen. A hydrogen release rate of approximately 5 x 10{sup -4} moles-H{sub 2}/gm-min was measured at 200{degrees}C. The hydride heat of formation was found to be 13.5 - 14 kcal/mole-H{sub 2}, somewhat lower than Mg{sub 2}Ni. The new fabrication method takes advantage of the high vapor transport of magnesium. It was found that Mg{sub 2}Ni produced by our low temperature process was better than conventional materials because it was single phase (no Mg phase) and could be fabricated with very small particle sizes. Hydride measurements on this material showed faster kinetic response than conventional material. The technique could potentially be applied to in-situ hydride bed fabrication with improved packing density, release kinetics, thermal properties and mechanical stability.

  2. Lightweight cryptography for constrained devices

    DEFF Research Database (Denmark)

    Alippi, Cesare; Bogdanov, Andrey; Regazzoni, Francesco

    2014-01-01

    Lightweight cryptography is a rapidly evolving research field that responds to the request for security in resource constrained devices. This need arises from crucial pervasive IT applications, such as those based on RFID tags where cost and energy constraints drastically limit the solution...

  3. Lightweight, Wearable, Metal Rubber Sensor

    Science.gov (United States)

    Hill, Andrea

    2015-01-01

    For autonomous health monitoring. NanoSonic, Inc., has developed comfortable garments with multiple integrated sensors designed to monitor astronaut health throughout long-duration space missions. The combined high electrical conductivity, low mechanical modulus, and environmental robustness of the sensors make them an effective, lightweight, and comfortable alternative to conventional use of metal wiring and cabling.

  4. Freestanding membrane composed of micro-ring array with ultrahigh sidewall aspect ratio for application in lightweight cathode arrays

    Science.gov (United States)

    Wang, Lanlan; Liu, Hongzhong; Jiang, Weitao; Gao, Wei; Chen, Bangdao; Li, Xin; Ding, Yucheng; An, Ningli

    2014-12-01

    A freestanding multilayer ultrathin nano-membrane (FUN-membrane) with a micro-ring array (MRA) is successfully fabricated through the controllable film deposition. Each micro-ring of FUN-membrane is 3 μm in diameter, 2 μm in height and sub-100 nm in sidewall thickness, demonstrating an ultrahigh sidewall aspect ratio of 20:1. In our strategy, a silica layer (200 nm in thickness), a chromium transition layer (5 nm-thick) and a gold layer (40 nm-thick), were in sequence deposited on patterned photoresist. After removal of the photoresist by lift-off process, a FUN-membrane with MRA was peeled off from the substrate, where the gold layer acted as a protecting layer to prevent the MRA from fracture. The FUN-membrane was then transferred to a flexible polycarbonate (PC) sheet coated with indium tin oxide (ITO) layer, which was then used as a flexible and lightweight cathode. Remarkably, the field emission effect of the fabricated FUN-membrane cathode performs a high field-enhancement factor of 1.2 × 104 and a low turn-on voltage of 2 V/μm, indicating the advantages of the sharp metal edge of MRA. Due to the rational design and material versatility, the FUN-membrane thus could be transferred to either rigid or flexible substrate, even curved surface, such as the skin of bio-robot's arm or leg. Additionally, the FUN-membrane composed of MRA with extremely high aspect ratio of insulator-metal sidewall, also provides potential applications in optical devices, lightweight and flexible display devices, and electronic eye imagers.

  5. Lightweight Space Tug body structure

    Science.gov (United States)

    Lager, J. R.

    1976-01-01

    Lightweight honeycomb sandwich construction using a wide variety of metal and fibrous composite faceskins was used in the design of a typical Space Tug skirt structure. Relatively low magnitude combined loading of axial compression and torsion resulted in designs using ultrathin faceskins, lightweight honeycomb cores, and thin faceskin/core adhesive bond layers. Two of the designs with metal faceskins (aluminum and titanium) and four with fibrous composite faceskins (using combinations of fiberglass, boron, and graphite) were evaluated through the fabrication and structural test of a series of small development panels. The two most promising concepts with aluminum and graphite/epoxy faceskins, were further evaluated through the fabrication and structural test of larger compression and shear panels. All panels tested exceeded design ultimate load levels, thereby, verifying the structural integrity of the selected designs. Projected skirt structural weights for the graphite/epoxy and aluminum concepts fall within original weight guidelines established for the Space Tug vehicle.

  6. Making Lightweight Structures By Vapor Deposition

    Science.gov (United States)

    Goela, Jitendra S.; Pickering, Michael A.; Taylor, Raymond L.

    1990-01-01

    Technique developed for fabrication of stiff, strong, lightweight structures of silicon carbide or other materials by any of several deposition processes. Structures made by method can have complicated shapes. Ability to manufacture complex shape from pure deposited SiC useful and leads to new products in several fields. These lightweight structures used as backup structures for optical components, as structural components in automotive, aerospace, and outer space applications, and as lightweight parts of furniture for outer space.

  7. Lightweight and Energy Efficient Heat Pump Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Future Spacecraft from the JPL will require increasingly sophisticated thermal control technology. A need exists for efficient, lightweight Vapor Compression Cycle...

  8. Modular Self-Rigidizing Lightweight Structures Project

    Data.gov (United States)

    National Aeronautics and Space Administration — An innovative structures concept has been developed that uses space qualified flexible thin film polyimide to produce ultra-lightweight inflation deployed...

  9. Spongent: A lightweight hash function

    DEFF Research Database (Denmark)

    Bogdanov, Andrey; Knežević, Miroslav; Leander, Gregor

    2011-01-01

    This paper proposes spongent - a family of lightweight hash functions with hash sizes of 88 (for preimage resistance only), 128, 160, 224, and 256 bits based on a sponge construction instantiated with a present-type permutation, following the hermetic sponge strategy. Its smallest implementations...... of serialization degree and speed. We explore some of its numerous implementation trade-offs. We furthermore present a security analysis of spongent. Basing the design on a present-type primitive provides confidence in its security with respect to the most important attacks. Several dedicated attack approaches...

  10. Manufacturing Precise, Lightweight Paraboloidal Mirrors

    Science.gov (United States)

    Hermann, Frederick Thomas

    2006-01-01

    A process for fabricating a precise, diffraction- limited, ultra-lightweight, composite- material (matrix/fiber) paraboloidal telescope mirror has been devised. Unlike the traditional process of fabrication of heavier glass-based mirrors, this process involves a minimum of manual steps and subjective judgment. Instead, this process involves objectively controllable, repeatable steps; hence, this process is better suited for mass production. Other processes that have been investigated for fabrication of precise composite-material lightweight mirrors have resulted in print-through of fiber patterns onto reflecting surfaces, and have not provided adequate structural support for maintenance of stable, diffraction-limited surface figures. In contrast, this process does not result in print-through of the fiber pattern onto the reflecting surface and does provide a lightweight, rigid structure capable of maintaining a diffraction-limited surface figure in the face of changing temperature, humidity, and air pressure. The process consists mainly of the following steps: 1. A precise glass mandrel is fabricated by conventional optical grinding and polishing. 2. The mandrel is coated with a release agent and covered with layers of a carbon- fiber composite material. 3. The outer surface of the outer layer of the carbon-fiber composite material is coated with a surfactant chosen to provide for the proper flow of an epoxy resin to be applied subsequently. 4. The mandrel as thus covered is mounted on a temperature-controlled spin table. 5. The table is heated to a suitable temperature and spun at a suitable speed as the epoxy resin is poured onto the coated carbon-fiber composite material. 6. The surface figure of the optic is monitored and adjusted by use of traditional Ronchi, Focault, and interferometric optical measurement techniques while the speed of rotation and the temperature are adjusted to obtain the desired figure. The proper selection of surfactant, speed or rotation

  11. Small and lightweight power amplifiers

    Science.gov (United States)

    Shams, Qamar A.; Barnes, Kevin N.; Fox, Robert L.; Moses, Robert W.; Bryant, Robert G.; Robinson, Paul C.; Shirvani, Mir

    2002-07-01

    The control of u wanted structural vibration is implicit in most of NASA's programs. Currently several approaches to control vibrations in large, lightweight, deployable structures and twin tail aircraft at high angles of attack are being evaluated. The Air Force has been examining a vertical tail buffet load alleviation system that can be integrated onboard an F/A-18 and flown. Previous wind tunnel and full-scale ground tests using distributed actuators have shown that the concept works; however, there is insufficient rom available onboard an F/A-18 to store current state-of- the-art system components such as amplifiers, DC-to-DC converter and a computer for performing vibration suppression. Sensor processing, power electronics, DC-to-DC converters, and control electronics that may be collocated with distributed actuators, are particularly desirable. Such electronic system would obviate the need for complex, centralized, control processing and power distribution components that will eliminate the weight associated with lengthy wiring and cabling networks. Several small and lightweight power amplifiers ranging from 300V pp to 650V pp have been designed using off the shelf components for different applications. In this paper, the design and testing of these amplifiers will be presented under various electrical loads.

  12. Freestanding membrane composed of micro-ring array with ultrahigh sidewall aspect ratio for application in lightweight cathode arrays

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Lanlan [State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049 (China); Liu, Hongzhong, E-mail: hzliu@mail.xjtu.edu.cn [State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049 (China); Jiang, Weitao, E-mail: wtjiang@mail.xjtu.edu.cn [State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049 (China); Gao, Wei [Key Laboratory of Mechanics on Western Disasters and Environment, Lanzhou University, Lanzhou 730000 (China); Chen, Bangdao [State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049 (China); Li, Xin [Department of Microelectronics, Xi’an Jiaotong University, Xi’an 710049 (China); Ding, Yucheng [State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049 (China); An, Ningli [Department of Packaging Engineering, Xi’an University of Technology, Xi’an 710048 (China)

    2014-12-15

    Graphical abstract: A freestanding multilayer ultrathin nano-membrane (FUN-membrane) with a micro-ring array (MRA), in which the dimension of each micro-ring is 3 μm in diameter, 2 μm in height and sub-100 nm in sidewall thickness is successfully fabricated, as shown in the SEM image of figure (a). Due to the MRA with ultrahigh aspect ratio of dielectric-metal sidewall, the FUN-membrane can be transferred to either rigid or flexible substrate to be used as the cathode for lightweight display panel, as shown in the schematic of figure (b). - Highlights: • Exploring a new fabrication method for the freestanding ultrathin nano-membrane (FUN-membrane). • FUN-membrane is composed of micro-ring array with ultrahigh aspect ratio of the insulator-metal sidewall. • The sharp metal edge of each micro-ring is preferred to be served as the micro-emitter. - Abstract: A freestanding multilayer ultrathin nano-membrane (FUN-membrane) with a micro-ring array (MRA) is successfully fabricated through the controllable film deposition. Each micro-ring of FUN-membrane is 3 μm in diameter, 2 μm in height and sub-100 nm in sidewall thickness, demonstrating an ultrahigh sidewall aspect ratio of 20:1. In our strategy, a silica layer (200 nm in thickness), a chromium transition layer (5 nm-thick) and a gold layer (40 nm-thick), were in sequence deposited on patterned photoresist. After removal of the photoresist by lift-off process, a FUN-membrane with MRA was peeled off from the substrate, where the gold layer acted as a protecting layer to prevent the MRA from fracture. The FUN-membrane was then transferred to a flexible polycarbonate (PC) sheet coated with indium tin oxide (ITO) layer, which was then used as a flexible and lightweight cathode. Remarkably, the field emission effect of the fabricated FUN-membrane cathode performs a high field-enhancement factor of 1.2 × 10{sup 4} and a low turn-on voltage of 2 V/μm, indicating the advantages of the sharp metal edge of MRA. Due

  13. High-Volume Production of Lightweight, Multi-Junction Solar Cells Using 6-inch GaAs Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In the proposed Phase II program, we will transition MicroLink's 6-inch epitaxial lift-off (ELO) solar cell fabrication process into a manufacturing platform capable...

  14. RFID security a lightweight paradigm

    CERN Document Server

    Khattab, Ahmed; Amini, Esmaeil; Bayoumi, Magdy

    2017-01-01

    This book provides a comprehensive treatment of security in the widely adopted, Radio Frequency Identification (RFID) technology. The authors present the fundamental principles of RFID cryptography in a manner accessible to a broad range of readers, enabling them to improve their RFID security design. This book also offers the reader a range of interesting topics portraying the current state-of-the-art in RFID technology and how it can be integrated with today’s Internet of Things (IoT) vision. The authors describe a first-of-its-kind, lightweight symmetric authenticated encryption cipher called Redundant Bit Security (RBS), which enables significant, multi-faceted performance improvements compared to existing cryptosystems. This book is a must-read for anyone aiming to overcome the constraints of practical implementation in RFID security technologies.

  15. EVOLUTION OF LIGHTWEIGHT WOOD COMPOSITES

    Directory of Open Access Journals (Sweden)

    Marius C. BARBU

    2016-01-01

    Full Text Available Lightweight boards and beams in the wood-based construction and furniture industry are not a new topic. The density reduction of panels using sandwich structure with light cores was confirmed by users like doors or mobile homes more than three decades ago. Today many ways to attain a lighter wooden structure are on offer, partially in industrial application. The first one is the use of light-weight wood species like balsa, lime, pine from southern hemisphere plantations etc. limited by the availability, strength properties, gluability and so on. A second one is the sandwich structure made from hard faces like thick veneer, thin plywood, particleboard or high density thin fiberboard and cores made from honeycomb paper, very light wood species or foams like the polystyrene one. A third way to produce a light structure is to reduce the core drastically, using predesigned skeletons with special shapes and connections to the faces. The engines for these developments are on the one hand the fast growing market of knockdown furniture and on the other hand the increasing costs for energy and raw materials. Additional factors that make weight saving a primary economical objective for most producers are transportation costs, easier handling and higher acceptance among the end users. Moreover, customers demand more for ergonomical solutions regarding packaging. Many patents were generated by researchers and developers for new one-stage production processes for sandwich panels with wood- and impregnated paper-based facings made from veneers, particles or fibres and a core consisting of expandable foams, particles or embedded hard skeletons. These ideas or prototypes could be integrated in existing continuous pressing lines for wood based panels keeping some of the advantages of the continuous production technique in matters of efficiency. Some of the challenges of the light weight wooden structure are the connection in half or final parts, resistance to

  16. Lightweight composite mirrors for telescopes Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Lightweight, steady and stiff mirrors are necessary to decrease cost of telescopes such as IXO and GenX used in special NASA missions. Low-density materials are...

  17. Vibro-acoustics of lightweight sandwich structures

    CERN Document Server

    Lu, Tianjian

    2014-01-01

    Vibro-Acoustics of Lightweight Sandwich Structures introduces the study of the coupled vibration and acoustic behavior of lightweight sandwich structures in response to harmonic force and sound pressure. This book focuses on the theoretical modeling and experimental investigation of lightweight sandwich structures in order to provide a predictive framework for vibro-acoustic characteristics of typical engineering structures. Furthermore, by developing solution tools, it concentrates on the influence of key systematic parameters leading to effective guidance for optimal structure design toward lightweight, high-stiffness and superior sound insulation capability. This book is intended for researchers, scientists, engineers and graduate students in mechanical engineering especially in structural mechanics, mechanics and acoustics. Fengxian Xin and Tianjian Lu both work at the School of Aerospace, Xi’an Jiaotong University.

  18. Lightweight Composite Materials for Heavy Duty Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Pruez, Jacky; Shoukry, Samir; Williams, Gergis; Shoukry, Mark

    2013-08-31

    The main objective of this project is to develop, analyze and validate data, methodologies and tools that support widespread applications of automotive lightweighting technologies. Two underlying principles are guiding the research efforts towards this objective: • Seamless integration between the lightweight materials selected for certain vehicle systems, cost-effective methods for their design and manufacturing, and practical means to enhance their durability while reducing their Life-Cycle-Costs (LCC). • Smooth migration of the experience and findings accumulated so far at WVU in the areas of designing with lightweight materials, innovative joining concepts and durability predictions, from applications to the area of weight savings for heavy vehicle systems and hydrogen storage tanks, to lightweighting applications of selected systems or assemblies in light–duty vehicles.

  19. Lightweight, High-Temperature Radiator Panels Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Lightweight, high-temperature radiators are needed for future, high-efficiency power conversion systems for Nuclear Electric Propulsion (NEP). Creare has developed...

  20. Novel Lightweight Magnets for Space Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — TYRC of Tallahassee, Florida will design, fabricate and test a novel magnet for space applications. This lightweight magnet will be designed to operate at higher...

  1. Aluminum-CNF Lightweight Radiator Components Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal relates to a new materials concept for an aluminum-carbon nanofiber composite, high thermal conductivity ultra lightweight material that will form the...

  2. Lightweight, High-Temperature Radiator Panels Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Lightweight, high-temperature radiators are needed for future, high-efficiency power conversion systems for Nuclear Electric Propulsion (NEP). Creare has developed...

  3. ATTENUATION AND FLANKING TRANSMISSION IN LIGHTWEIGHT STRUCTURES

    DEFF Research Database (Denmark)

    Brunskog, Jonas; Lhomond, Alice; Ohlrich, Mogens

    2007-01-01

    In this paper the attenuation and flanking transmissions of impact noise in lightweight building structures is studied using a modal approach. The structural field is mainly analysed, putting the main attention to the parts being important in the modelling. The amount of attenuation produced...... by the periodically reinforcing beams used in lightweight building structures is analysed. The consequence of these factors in modelling flanking transmission is also discussed....

  4. Industrial Engineering Lifts Off at Kennedy Space Center

    Science.gov (United States)

    Barth, Tim

    1998-01-01

    When the National Aeronautics and Space Administration (NASA) began the Space Shuttle Program, it did not have an established industrial engineering (IE) capability for several probable reasons. For example, it was easy for some managers to dismiss IE principles as being inapplicable at NASA's John F. Kennedy Space Center (KSC). When NASA was formed by the National Aeronautics and Space Act of 1958, most industrial engineers worked in more traditional factory environments. The primary emphasis early in the shuttle program, and during previous human space flight programs such as Mercury and Apollo, was on technical accomplishments. Industrial engineering is sometimes difficult to explain in NASA's highly technical culture. IE is different in many ways from other engineering disciplines because it is devoted to process management and improvement, rather than product design. Images of clipboards and stopwatches still come to the minds of many people when the term industrial engineering is mentioned. The discipline of IE has only recently begun to gain acceptance and understanding in NASA. From an IE perspective today, the facilities used for flight hardware processing at KSC are NASA's premier factories. The products of these factories are among the most spectacular in the world: safe and successful launches of shuttles and expendable vehicles that carry tremendous payloads into space.

  5. Lift-off for World Year of Physics

    CERN Multimedia

    2005-01-01

    Over 1000 participants, including eight Nobel Prize Laureates, personalities from the world of science and close to 500 students from 70 countries took part in the "Physics for Tomorrow" conference at UNESCO headquarters in Paris on 13 January 2005. The event marked the official launch of the International Year of Physics, proclaimed by the United Nations. The International Year aims to highlight the importance of physics and its contribution to the development of many other scientific disciplines. It is also to help fight the current lack of enthusiasm for sciences among young people. Throughout 2005, events will be organized across the world to debate physics and it implications to society. The conference was organized by UNESCO, the lead UN organization for the International Year, and by the physics community, in particular by CERN, CNRS and CEA, EU Commission, EPS, IUPAP and others. CERN Director-General, Robert Aymar, participating to the Inauguration Session of the Launch Event of the International Y...

  6. Entrenched metal lift-off using a novel bilayer process

    Science.gov (United States)

    Dubois, Thomas D.; Tranjan, Farid M.; Jones, Susan K.; Bobbio, Stephen M.; Kellam, Mark D.; Frieser, Rudolph G.; Jones, A. D.

    1990-01-01

    This paper will discuss the preparation and characterization of a modified photoresist and describe its use in a novel bilayer process. The modified photoresist solutions are prepared by dissolving enough cyclic phosphonitrilic chloride trimer, PNCT, in commercially available photoresist solutions to achieve phosphorus concentrations of 10 to 12 weight percent in the resulting films. FTNMR and FTIR data will be presented which demonstrate that the cyclic phosphonitrilic chloride trimer does not undergo chemical reaction with the components of the photoresist in the photoresist solutions or photoresist films. The exposure threshold of the PNCT modified photoresist films is 1.5 times greater than that of the unmodified films. Experimental data will be discussed which suggests the decrease in exposure threshold is the result of a relatively lower concentration of photoactive compound in the PNCT modified films. The PNCT modified films will be shown to provide resolution comparable to that of the unmodified photoresist films and yield a process window of better than 20%. A mechanism for the formation of the 02/N2 plasma resistant etch barrier formed during 02/N2 plasma etching will be discussed. Finally, a bilayer process which uses the PNCT modified photoresist in generating metal features entrenched in polyimide will be presented.

  7. 5, 4, 3, 2, 1… lift-off!

    CERN Multimedia

    Laëtitia Pedroso

    2011-01-01

    The protracted efforts of 56 institutes across the world, including CERN, have finally come to fruition with the launch of the Space Shuttle Endeavour transporting the AMS Alpha Magnetic Spectrometer to the International Space Station (ISS). The launch was originally scheduled for 29 April but had to be pushed back to Monday 16 May for technical reasons. The data collected by AMS will be analysed in particular in the experiment's brand new control centre currently under construction at CERN (Building 946) and due for completion by June. Stay tuned to the CERN Bulletin for news of any discoveries. A selection of images taken by Micheal Struik at Kennedy Space Centre on the day of the launch (click on the image to enlarge it):   Watch the CERN webcast of the Endeavour Shuttle launch and the CERN Video News.   var flash_video_player=get_video_player_path(); insert_player_for_external('Video/Public/Movies/2011/CERN-MOVIE-2011-068/CERN-MOVIE-2011-068-0753-kbps-640x360-25-fps-audio...

  8. Geopolymerization of lightweight aggregate waste

    Directory of Open Access Journals (Sweden)

    Labrincha, J. A.

    2008-09-01

    Full Text Available Geopolymerization is a viable way to process and re-use alumino-silicate industrial waste while producing highstrength, high chemical inertia materials that can effectively immobilize other industrial by-products, and even hazardous waste. In this study industrial waste from different stages of the manufacture of lightweight expanded clay aggregate was characterized for its possible transformation, via alkali activation, to geopolymers. The ultimate aim was to assess the possibility of using such geopolymers to develop thermal and acoustic insulation panels. The containment of hazardous materials is another important application for these new materials. Geopolymers were prepared for this study with different particles size distributions and activator concentrations. Their mechanical properties, composition and microstructure were characterized and a material with promising insulating properties was produced. A preliminary analysis was conducted of the salt formation observed in these geopolymers, the chief drawback to their use.La geopolimerización es una manera viable para procesar y agregar valor a los residuos industriales de alumino-silicato dando lugar a materiales con elevadas resistencias mecánmicas, alta inercia química y que permiten encapsular otros residuos, incluso peligrosos. Los residuos industriales que proceden de diversos tipos de arcillas para la fabricación de áridos ligeros se han caracterizado para la producción de geopolímeros mediante el proceso de ataque alcalino. Su incorporación en una matriz geopolimérica permite la posibilidad de desarrollo de paneles de aislamiento (térmico y acústico. Además, la inmovilización de materiales peligrosos es un logro adicional importante. Los geopolímeros se han producido con fórmulas diferentes y se han caracterizado sus propiedades mecánicas, composición y microestructura, para dar lugar a una composición interesante con propiedades aislantes. Se ha llevado a cabo

  9. The Design of a Lightweight RFID Middleware

    Directory of Open Access Journals (Sweden)

    Fengqun Lin

    2009-10-01

    Full Text Available Radio Frequency Identification (RFID middleware is often regarded as the central nervous system of RFID systems. In this paper, a lightweight RFID middleware is designed and implemented without the need of an Application Level Events (ALE structure, and its implementation process is described using a typical commerical enterprise. A short review of the current RFID middleware research and development is also included. The characteristics of RFID middleware are presented with a two-centric framework. The senarios of RFID data integration based on the simplified structure are provided to illuminats the design and implementation of the lightweight middleware structure and its development process. The lightweight middleware is easy to maintain and extend because of the simplified and streamlined structure and the short development cycle.

  10. A lightweight shape-memory magnesium alloy.

    Science.gov (United States)

    Ogawa, Yukiko; Ando, Daisuke; Sutou, Yuji; Koike, Junichi

    2016-07-22

    Shape-memory alloys (SMAs), which display shape recovery upon heating, as well as superelasticity, offer many technological advantages in various applications. Those distinctive behaviors have been observed in many polycrystalline alloy systems such as nickel titantium (TiNi)-, copper-, iron-, nickel-, cobalt-, and Ti-based alloys but not in lightweight alloys such as magnesium (Mg) and aluminum alloys. Here we present a Mg SMA showing superelasticity of 4.4% at -150°C and shape recovery upon heating. The shape-memory properties are caused by reversible martensitic transformation. This Mg alloy includes lightweight scandium, and its density is about 2 grams per cubic centimeter, which is one-third less than that of practical TiNi SMAs. This finding raises the potential for development and application of lightweight SMAs across a number of industries.

  11. Exploring Energy Efficiency of Lightweight Block Ciphers

    DEFF Research Database (Denmark)

    Banik, Subhadeep; Bogdanov, Andrey; Regazzoni, Francesco

    2016-01-01

    lightweight block ciphers, and thereby try to predict the optimal value of r at which an r-round unrolled architecture for a cipher is likely to be most energy efficient. We also try to relate our results to some physical design parameters like the signal delay across a round and algorithmic parameters like......In the last few years, the field of lightweight cryptography has seen an influx in the number of block ciphers and hash functions being proposed. One of the metrics that define a good lightweight design is the energy consumed per unit operation of the algorithm. For block ciphers, this operation...... is the encryption of one plaintext. By studying the energy consumption model of a CMOS gate, we arrive at the conclusion that the energy consumed per cycle during the encryption operation of an r-round unrolled architecture of any block cipher is a quadratic function in r. We then apply our model to 9 well known...

  12. Infinte Periodic Structure of Lightweight Elements

    DEFF Research Database (Denmark)

    Domadiya, Parthkumar Gandalal; Andersen, Lars Vabbersgaard; Sorokin, Sergey

    2013-01-01

    Lightweight wooden structures have become more popular as a sustainable, environmental- friendly and cost-effective alternative to concrete, steel and masonry buildings. However, there are certain drawbacks regarding noise and vibration due to the smaller weight and stiffness of wooden buildings...... for proper dynamic assessment of lightweight buildings. Instead, this paper discusses and compares the use of finite element analysis and a wave approach based on Floquet theory. The present analysis has focus on the effect of periodicity on vibration transmission within semi-infinite beam structures. Two....... Furthermore, lightweight building elements are typically periodic structures that behave as filters for sound propagation within certain frequency ranges (stop bands), thus only allowing transmission within the pass bands. Hence, traditional methods based on statistical energy analysis cannot be used...

  13. LIGHT-WEIGHT LOAD-BEARING STRUCTURE

    DEFF Research Database (Denmark)

    2009-01-01

    The invention relates to a light-weight load-bearing structure (1) with optimized compression zone (2), where along one or more compression zones (2) in the structure (1) to be cast a core (3) of strong concrete is provided, which core (3) is surrounded by concrete of less strength (4) compared...... to the core (3) of strong concrete. The invention also relates to a method of casting of light-weight load-bearing structures (1) with optimized compression zone (2) where one or more channels, grooves, ducts, pipes and/or hoses (5) formed in the load-bearing structure (1) serves as moulds for moulding one...... or more cores (3) of strong concrete in the light-weight load-bearing structure (1)....

  14. Southern Regional Center for Lightweight Innovative Design

    Energy Technology Data Exchange (ETDEWEB)

    Horstemeyer, Mark F. [Mississippi State Univ., Mississippi State, MS (United States); Wang, Paul [Mississippi State Univ., Mississippi State, MS (United States)

    2011-12-27

    The three major objectives of this Phase III project are: To develop experimentally validated cradle-to-grave modeling and simulation tools to optimize automotive and truck components for lightweighting materials (aluminum, steel, and Mg alloys and polymer-based composites) with consideration of uncertainty to decrease weight and cost, yet increase the performance and safety in impact scenarios; To develop multiscale computational models that quantify microstructure-property relations by evaluating various length scales, from the atomic through component levels, for each step of the manufacturing process for vehicles; and To develop an integrated K-12 educational program to educate students on lightweighting designs and impact scenarios.

  15. Environmental assessment of lightweight electric vehicles

    CERN Document Server

    Egede, Patricia

    2017-01-01

    This monograph adresses the challenge of the environmental assessment of leightweight electric vehicles. It poses the question whether the use of lightweight materials in electric vehicles can reduce the vehicles’ environmental impact and compares the environmental performance of a lightweight electric vehicle (LEV) to other types of vehicles. The topical approach focuses on methods from life cycle assessment (LCA), and the book concludes with a comprehensive concept on the environmental assessment of LEVs. The target audience primarily comprises LCA practitioners from research institutes and industry, but it may also be beneficial for graduate students specializing in the field of environmental assessment.

  16. Fixed Sagittal Plane Imbalance

    OpenAIRE

    Savage, Jason W.; Patel, Alpesh A.

    2014-01-01

    Study Design Literature review. Objective To discuss the evaluation and management of fixed sagittal plane imbalance. Methods A comprehensive literature review was performed on the preoperative evaluation of patients with sagittal plane malalignment, as well as the surgical strategies to address sagittal plane deformity. Results Sagittal plane imbalance is often caused by de novo scoliosis or iatrogenic flat back deformity. Understanding the etiology and magnitude of sagittal malalignment is ...

  17. Paper Sludge Reuse in Lightweight Aggregates Manufacturing.

    Science.gov (United States)

    Chen, How-Ji; Hsueh, Ying-Chih; Peng, Ching-Fang; Tang, Chao-Wei

    2016-10-27

    The lightweight aggregates used by the civil engineering market are sintered at a high temperature, about 1200 °C. In times of high energy prices and regulation of carbon dioxide emissions, lightweight aggregate products of the high-temperature process in sales marketing are not readily accepted. This study developed a sintered-type paper sludge lightweight aggregate. In order to reduce energy consumption, substitution of some reservoir sediment clay in paper sludge substitutes is to be expected. The study used two types of paper sludge (green clay paper sludge and paper pulp sludge). The sintering temperature was reduced effectively as the green clay paper sludge was substituted for some of the reservoir sediment clay, and the optimum substitute ranges of green clay paper sludge were 10%-50%. The optimum substitute ranges of the paper pulp sludge were 10%-40%. Test results show that the properties of aggregates have a particle density of 0.66-1.69 g/cm³, a water absorption of 5%-30%, and a loss on ignition of 10%-43%. The loss on ignition of aggregate became greater with the increase in paper sludge content. This means that the calorific value provided by the paper sludge will increase as paper sludge content increases. Paper sludge can therefore be considered a good material to provide heat energy for sintering lightweight aggregate.

  18. Lightweight solar concentrator structures, phase 2

    Science.gov (United States)

    Williams, Brian E.; Kaplan, Richard B.

    1993-01-01

    This report summarizes the results of the program conducted by Ultramet under SBIR Phase 2 Contract NAS3-25418. The objective of this program was to develop lightweight materials and processes for advanced high accuracy Space Solar Concentrators using rigidized foam for the substrate structure with an integral optical surface.

  19. Method of fabricating lightweight honeycomb structures

    Science.gov (United States)

    Goela, Jitendra S. (Inventor); Pickering, Michael (Inventor); Taylor, Raymond L. (Inventor)

    1992-01-01

    A process is disclosed for fabricating lightweight honeycomb type structures out of material such as silicon carbide (SiC) and silicon (S). The lightweight structure consists of a core to define the shape and size of the structure. The core is coated with an appropriate deposit such as SiC or Si to give the lightweight structure strength and stiffness and for bonding the lightweight structure to another surface. The core is fabricated from extremely thin ribs of appropriately stiff and strong material such as graphite. First, a graphite core consisting of an outer hexagonal cell with six inner triangular cells is constructed from the graphite ribs. The graphite core may be placed on the back-up side of a SiC faceplate and then coated with SiC to produce a monolithic structure without the use of any bonding agent. Cores and methods for the fabrication thereof in which the six inner triangular cells are further divided into a plurality of cells are also disclosed.

  20. A Lightweight Mobile RSVP for Unicast

    Institute of Scientific and Technical Information of China (English)

    CHEN Wen; LEI Fei-yu; CHEN Xi; WANG Wei-nong

    2005-01-01

    This paper presents a lighter protocol, and it removes the multicast burdens from RSVP to adapt to unicast applications. At the same time, when RSVP is used in wireless networks, some issues about mobility raise popular concerns. The proposed protocol a lightweight mobile RSVP protocol, solves the problems by the following mechanisms:changeless flow identifier, a new state management and "refresh" mechanism.

  1. Lightweight concrete with enhanced neutron shielding

    Energy Technology Data Exchange (ETDEWEB)

    Brindza, Paul Daniel; Metzger, Bert Clayton

    2016-09-13

    A lightweight concrete containing polyethylene terephthalate in an amount of 20% by total volume. The concrete is enriched with hydrogen and is therefore highly effective at thermalizing neutrons. The concrete can be used independently or as a component of an advanced neutron radiation shielding system.

  2. Cryptanalysis of Some Lightweight Symmetric Ciphers

    DEFF Research Database (Denmark)

    Abdelraheem, Mohamed Ahmed Awadelkareem Mohamed Ahmed

    on a variant of PRESENT with identical round keys. We propose a new attack named the Invariant Subspace Attack that was specifically mounted against the lightweight block cipher PRINTcipher. Furthermore, we mount several attacks on a recently proposed stream cipher called A2U2....

  3. FY 2012 Lightweight Materials Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-04-15

    The FY 2012 Annual Progress Report for Lightweight Materials provides a detailed description of the activities and technical accomplishments which focuses on the development and validation of advanced materials and manufacturing technologies to significantly reduce light and heavy duty vehicle weight without compromising other attributes such as safety, performance, recyclability, and cost.

  4. Vehicle Lightweighting: 40% and 45% Weight Savings Analysis: Technical Cost Modeling for Vehicle Lightweighting

    Energy Technology Data Exchange (ETDEWEB)

    Mascarin, Anthony [Idaho National Lab. (INL), Idaho Falls, ID (United States); Hannibal, Ted [Idaho National Lab. (INL), Idaho Falls, ID (United States); Raghunathan, Anand [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ivanic, Ziga [Idaho National Lab. (INL), Idaho Falls, ID (United States); Francfort, James [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-04-01

    The U.S. Department of Energy’s Vehicle Technologies Office, Materials area commissioned a study to model and assess manufacturing economics of alternative design and production strategies for a series of lightweight vehicle concepts. The strategic targets were a 40% and a 45% mass reduction relative to a standard North American midsize passenger sedan at an effective cost of $3.42 per pound (lb) saved. The baseline vehicle was an average of several available vehicles in this class. Mass and cost breakdowns from several sources were used, including original equipment manufacturers’ (OEMs’) input through U.S. Department of Energy’s Vehicle Technologies Office programs and public presentations, A2Mac1 LLC’s teardown information, Lotus Engineering Limited and FEV, Inc. breakdowns in their respective lightweighting studies, and IBIS Associates, Inc.’s decades of experience in automotive lightweighting and materials substitution analyses. Information on lightweighting strategies in this analysis came from these same sources and the ongoing U.S. Department of Energy-funded Vehma International of America, Inc. /Ford Motor Company Multi-Material Lightweight Prototype Vehicle Demonstration Project, the Aluminum Association Transportation Group, and many United States Council for Automotive Research’s/United States Automotive Materials Partnership LLC lightweight materials programs.

  5. Behavior of Reinforced Concrete Frames In-Filled with Lightweight Materials Under Seismic Loads

    Directory of Open Access Journals (Sweden)

    Iswandi Imran

    2009-01-01

    Full Text Available This paper presents an experimental and analytical research conducted to study the in-plane behavior of reinforced concrete (R/C frames in-filled with lightweight materials. The tests were performed on two single bay, single story in-filled frame specimens with ½ scale models. One of the test specimens was in-filled with lightweight materials, i.e. autoclaved aerated concrete (AAC blocks, and the other, used as the comparison, was in-filled with clay brick materials. The loading used in the tests was in the form of cyclic in-plane lateral loads, simulating earthquake forces. Behavior of the frame structures was evaluated through the observed strength and deformation characteristics, the measured hysteretic energy dissipation capacity and the measured ductility. The experimental results show that the R/C frame in-filled with AAC blocks exhibited better performance under in-plane lateral loads than that in-filled with conventional clay bricks. In the analytical work, the performance of some analytical models available in the literature was evaluated in simulating the experimental results

  6. Cryostable lightweight frit bonded silicon mirror

    Science.gov (United States)

    Anthony, F.; McCarter, D.; Tangedahl, M.; Content, D.

    The excellent polishability, low density and relatively high stiffness of silicon make it an attractive candidate for optical applications that require superior performance. Assembly of silicon details by means of glass frit bonding permits significant light weighting thus enhancing the benefit of silicon mirrors. To demonstrate the performance potential, a small lightweight glass frit bonded silicon mirror was fabricated and tested for cryoability. The test mirror was 12.5cm in diameter with a 60cm spherical radius and a maximum thickness, at the perimeter, of 2.5cm. A machined silicon core was used to stiffen the two face sheets of the silicon sandwich. These three elements were assembled, by glass frit bonding, to form the substrate that was polished. The experimental evaluation in a liquid nitrogen cryostat, demonstrated cryostability performance significantly better than required by the mirror specification. Key WordsCryostable, Lightweight, Silicon, Frit Bond, Spherical, Mirror

  7. Lightweight composite fighting cover prototype development program

    Energy Technology Data Exchange (ETDEWEB)

    Wrenn, G.E. Jr.; Frame, B.J.; Gwaltney, R.C.; Akerman, M.A.

    1996-07-01

    The U.S. Army Field Assistance Science and Technology Program requested Oak Ridge National Laboratory (ORNL) to demonstrate the use of lightweight composite materials in construction of overhead covers for reinforced infantry fighting positions. In recent years, ORNL researchers have designed and tested several concepts for lightweight ballistic protection structures, and they have developed numerous prototype composite structures for military and civilian applications. In the current program, composite panel designs and materials are tested and optimized to meet anticipated static and dynamic load conditions for the overhead cover structure. Ten prototype composite covers were built at ORNL for use in Army field tests. Each composite cover has a nominal surface area of 12 ft[sup 2] and a nominal weight of 8 lb. Four of the prototypes are made with folding sections to improve their handling characteristics. The composite covers exhibit equivalent performance in Army field tests to covers made with conventional materials that weigh four times as much.

  8. Lightweight Service Oriented Architecture for Pervasive Computing

    CERN Document Server

    Tigli, Jean-Yves; Rey, Gaetan; Hourdin, Vincent; Riveill, Michel

    2011-01-01

    Pervasive computing appears like a new computing era based on networks of objects and devices evolving in a real world, radically different from distributed computing, based on networks of computers and data storages. Contrary to most context-aware approaches, we work on the assumption that pervasive software must be able to deal with a dynamic software environment before processing contextual data. After demonstrating that SOA (Service oriented Architecture) and its numerous principles are well adapted for pervasive computing, we present our extended SOA model for pervasive computing, called Service Lightweight Component Architecture (SLCA). SLCA presents various additional principles to meet completely pervasive software constraints: software infrastructure based on services for devices, local orchestrations based on lightweight component architecture and finally encapsulation of those orchestrations into composite services to address distributed composition of services. We present a sample application of t...

  9. Lightweight Protective Coatings For Titanium Alloys

    Science.gov (United States)

    Wiedemann, Karl E.; Taylor, Patrick J.; Clark, Ronald K.

    1992-01-01

    Lightweight coating developed to protect titanium and titanium aluminide alloys and titanium-matrix composite materials from attack by environment when used at high temperatures. Applied by sol-gel methods, and thickness less than 5 micrometers. Reaction-barrier and self-healing diffusion-barrier layers combine to protect titanium alloy against chemical attack by oxygen and nitrogen at high temperatures with very promising results. Can be extended to protection of other environmentally sensitive materials.

  10. Aladin Lite: Lightweight sky atlas for browsers

    Science.gov (United States)

    Boch, Thomas

    2014-02-01

    Aladin Lite is a lightweight version of the Aladin tool, running in the browser and geared towards simple visualization of a sky region. It allows visualization of image surveys (JPEG multi-resolution HEALPix all-sky surveys) and permits superimposing tabular (VOTable) and footprints (STC-S) data. Aladin Lite is powered by HTML5 canvas technology and is easily embeddable on any web page and can also be controlled through a Javacript API.

  11. LUCA:Lightweight Ubiquitous Computing Architecture

    Institute of Scientific and Technical Information of China (English)

    SUN Dao-qing; CAO Qi-ying

    2009-01-01

    Lightweight ubiquitous computing security architecture was presented. Lots of our recent researches have been integrated in this architecture. And the main current researches in the related area have also been absorbed. The main attention of this paper was providing a compact and realizable method to apply ubiquitous computing into our daily lives under sufficient secure guarantee. At last, the personal intelligent assistant system was presented to show that this architecture was a suitable and realizable security mechanism in solving the ubiquitous computing problems.

  12. High-Volume Production of Lightweight Multijunction Solar Cells

    Science.gov (United States)

    Youtsey, Christopher

    2015-01-01

    MicroLink Devices, Inc., has transitioned its 6-inch epitaxial lift-off (ELO) solar cell fabrication process into a manufacturing platform capable of sustaining large-volume production. This Phase II project improves the ELO process by reducing cycle time and increasing the yield of large-area devices. In addition, all critical device fabrication processes have transitioned to 6-inch production tool sets designed for volume production. An emphasis on automated cassette-to-cassette and batch processes minimizes operator dependence and cell performance variability. MicroLink Devices established a pilot production line capable of at least 1,500 6-inch wafers per month at greater than 80 percent yield. The company also increased the yield and manufacturability of the 6-inch reclaim process, which is crucial to reducing the cost of the cells.

  13. Southern Regional Center for Lightweight Innovative Design

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Paul T. [Mississippi State Univ., Mississippi State, MS (United States)

    2012-12-01

    The Southern Regional Center for Lightweight Innovative Design (SRCLID) has developed an experimentally validated cradle-to-grave modeling and simulation effort to optimize automotive components in order to decrease weight and cost, yet increase performance and safety in crash scenarios. In summary, the three major objectives of this project are accomplished: To develop experimentally validated cradle-to-grave modeling and simulation tools to optimize automotive and truck components for lightweighting materials (aluminum, steel, and Mg alloys and polymer-based composites) with consideration of uncertainty to decrease weight and cost, yet increase the performance and safety in impact scenarios; To develop multiscale computational models that quantify microstructure-property relations by evaluating various length scales, from the atomic through component levels, for each step of the manufacturing process for vehicles; and To develop an integrated K-12 educational program to educate students on lightweighting designs and impact scenarios. In this final report, we divided the content into two parts: the first part contains the development of building blocks for the project, including materials and process models, process-structure-property (PSP) relationship, and experimental validation capabilities; the second part presents the demonstration task for Mg front-end work associated with USAMP projects.

  14. Engineering properties of high strength lightweight concrete

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-08-01

    The strength to weight ratio of high strength lightweight concrete is not its only advantage. The artificial lightweight aggregate combines physically and, to a lesser extent, chemically with the surrounding cement matrix to produce an impermeable and durable concrete. The engineering properties of the concrete are sensitive to the proportions and nature of its constituents, and to its production methods. Supplementary cementing materials and chemical admixtures are used to develop the increased strength and durability. Thermal movements, shrinkage and creep are within workable limits. Fatigue resistance is probably at least as good as that achieved by equivalent strength normal density concretes but there is limited data on this topic. Deleterious effects of admixtures supplied in high dosages have not been identified but neither have they been investigated. The relationship between the tensile strength of the material and its uniaxial compressive strength is not robust. The shear capacity of structural elements is not adequately covered by most existing design codes. In common with all concretes, the stability of high strength lightweight concrete is reduced when water retained within it freezes or vaporises. A satisfactory freeze thaw behaviour can be readily achieved but, under fire conditions, the impermeability of the cement matrix limits the venting of water vapour at the concrete surface. Explosive failures can result. (Author)

  15. Southern Regional Center for Lightweight Innovative Design

    Energy Technology Data Exchange (ETDEWEB)

    None

    2012-08-24

    The Southern Regional Center for Lightweight Innovative Design (SRCLID) has developed an experimentally validated cradle-to-grave modeling and simulation effort to optimize automotive components in order to decrease weight and cost, yet increase performance and safety in crash scenarios. In summary, the three major objectives of this project are accomplished: To develop experimentally validated cradle-to-grave modeling and simulation tools to optimize automotive and truck components for lightweighting materials (aluminum, steel, and Mg alloys and polymer-based composites) with consideration of uncertainty to decrease weight and cost, yet increase the performance and safety in impact scenarios; To develop multiscale computational models that quantify microstructure-property relations by evaluating various length scales, from the atomic through component levels, for each step of the manufacturing process for vehicles; and To develop an integrated K-12 educational program to educate students on lightweighting designs and impact scenarios. In this final report, we divided the content into two parts: the first part contains the development of building blocks for the project, including materials and process models, process-structure-property (PSP) relationship, and experimental validation capabilities; the second part presents the demonstration task for Mg front-end work associated with USAMP projects.

  16. Unitals in Projective Planes

    CERN Document Server

    Barwick, Susan

    2008-01-01

    Unitals are key structures in projective planes, and have connections with other structures in algebra. This book presents a monograph on unitals embedded in finite projective planes. It offers a survey of the research literature on embedded unitals. It is suitable for graduate students and researchers who want to learn about this topic

  17. Design of ultra-lightweight concrete: towards monolithic concrete structures

    Directory of Open Access Journals (Sweden)

    Yu Qing Liang

    2014-04-01

    Full Text Available This study addresses the development of ultra-lightweight concrete. A moderate strength and an excellent thermal conductivity of the lightweight concrete are set as the design targets. The designed lightweight aggregates concrete is targeted to be used in monolithic concrete façade structure, performing as both load bearing element and thermal insulator. The developed lightweight concrete shows excellent thermal properties, with a low thermal conductivity of about 0.12 W/(m·K; and moderate mechanical properties, with 28-day compressive strengths of about 10-12 N/mm . This combination of values exceeds, to the researchers’ knowledge, the performance of all other lightweight building materials. Furthermore, the developed lightweight concrete possesses excellent durability properties.

  18. Lightweight Thermally Stable Multi-Meter Aperture Submillimeter Reflectors Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Future astrophysics missions will require lightweight, thermally stable, submillimeter reflectors in sizes of 4m and greater. To date, graphite fiber reinforced...

  19. Laser Additive Manufacturing and Bionics: Redefining Lightweight Design

    Science.gov (United States)

    Emmelmann, C.; Sander, P.; Kranz, J.; Wycisk, E.

    New layer wise manufacturing technologies such as Laser Additive Manufacturing (LAM) allow innovative approaches to product design. Especially for lightweight design in aircraft applications LAM offers new possibilities for load-adapted structures. However, to fully capture lightweight potential of LAM technologies new design guidelines and processes have to be developed. A novel approach to extreme lightweight design is realized by incorporating structural optimization tools, bionic structures and LAM guidelines into one design process. By consequently following this design process designers can achieve lightweight savings in designing new aircraft structures.

  20. Lightweight Rubbery Aerogel Composites for High Performance Protection Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Aspen Aerogels Inc. (AAI) and the Man Vehicle Laboratory (MVL) at the Massachusetts Institute of Technology propose to develop nanostructured, lightweight, rubbery...

  1. Experimental Evaluation of Lightweight AAC Masonry Wall Prisms with Ferrocement Layers in Compression and Flexure

    KAUST Repository

    Abdel Mooty, Mohamed

    2012-05-01

    An experimental program is designed to evaluate the performance of lightweight autoclaved aerated concrete masonry wall strengthened using ferrocement layers, in a sandwich structure, under in-plane compression and out-of-plane bending. The 25 mm thick ferrocement mortar is reinforced with steel welded wire mesh of 1 mm diameters at 15 mm spacing. Different types of shear connectors are used to evaluate their effect on failure loads. The effect of different design parameters on the wall strength are considered including wall thickness, mortar strength, and type and distribution of shear connectors. A total of 20 prisms are tested in compression and 5 prisms are tested under bending. The proposed ferrocement strengthening technique is easy to apply on existing wall system and results in significant strength and stiffness enhancement of the tested wall specimens. © (2012) Trans Tech Publications.

  2. Type Classes for Lightweight Substructural Types

    Directory of Open Access Journals (Sweden)

    Edward Gan

    2015-02-01

    Full Text Available Linear and substructural types are powerful tools, but adding them to standard functional programming languages often means introducing extra annotations and typing machinery. We propose a lightweight substructural type system design that recasts the structural rules of weakening and contraction as type classes; we demonstrate this design in a prototype language, Clamp. Clamp supports polymorphic substructural types as well as an expressive system of mutable references. At the same time, it adds little additional overhead to a standard Damas-Hindley-Milner type system enriched with type classes. We have established type safety for the core model and implemented a type checker with type inference in Haskell.

  3. Longbow: A Lightweight Remote Job Submission Tool

    Directory of Open Access Journals (Sweden)

    James Gebbie-Rayet

    2016-01-01

    Full Text Available We present Longbow, a lightweight console-based remote job submission tool and library. Longbow allows the user to quickly and simply run jobs on high performance computing facilities without leaving their familiar desktop environment. Not only does Longbow greatly simplify the management of compute- intensive jobs for experienced researchers, it also lowers the technical barriers surrounding high perfor-mance computation for the next generation of scientists and engineers. Longbow has already been used to remotely submit jobs in a number of projects and has the potential to redefine the manner in which high performance computers are used.

  4. Lightweight Cryptography for Passive RFID Tags

    DEFF Research Database (Denmark)

    David, Mathieu

    2012-01-01

    among the smallest in the published literature and aims at being implemented on printed electronics RFID tags. Then, we compare different cryptographic primitives based on their key parameters: throughput, area, power consumption and level of security. Our main concern is the integrability...... of an integrator for a particular application. Finally, we conclude that the research for finding robust cryptographic primitive in the branch of lightweight cryptography still has some nice days ahead, and that providing a secure cryptosystem for printed electronics RFID tags remains an open research topic....

  5. Fixed sagittal plane imbalance.

    Science.gov (United States)

    Savage, Jason W; Patel, Alpesh A

    2014-12-01

    Study Design Literature review. Objective To discuss the evaluation and management of fixed sagittal plane imbalance. Methods A comprehensive literature review was performed on the preoperative evaluation of patients with sagittal plane malalignment, as well as the surgical strategies to address sagittal plane deformity. Results Sagittal plane imbalance is often caused by de novo scoliosis or iatrogenic flat back deformity. Understanding the etiology and magnitude of sagittal malalignment is crucial in realignment planning. Objective parameters have been developed to guide surgeons in determining how much correction is needed to achieve favorable outcomes. Currently, the goals of surgery are to restore a sagittal vertical axis Sagittal plane malalignment is an increasingly recognized cause of pain and disability. Treatment of sagittal plane imbalance varies according to the etiology, location, and severity of the deformity. Fixed sagittal malalignment often requires complex reconstructive procedures that include osteotomy correction. Reestablishing harmonious spinopelvic alignment is associated with significant improvement in health-related quality-of-life outcome measures and patient satisfaction.

  6. 76 FR 42137 - Certain Lightweight Thermal Paper From Germany; Remand Proceedings

    Science.gov (United States)

    2011-07-18

    ... COMMISSION Certain Lightweight Thermal Paper From Germany; Remand Proceedings AGENCY: United States...-1127 concerning certain lightweight thermal paper (``LWTP'') from Germany. For further information... certain lightweight thermal paper from Germany that the Department of Commerce found were sold at...

  7. Lightweight design of automotive front crossbeam assembly

    Institute of Scientific and Technical Information of China (English)

    Yao Zaiqi; Liu Qiang; Ma Fangwu; Zhao Fuquan; Liu Zongwei; Wang Guan; Wan Yinhui; Li Luoxing

    2012-01-01

    This paper reviews the development course of the front crossbeam assembly for a self-owned brand vehicle model based on lightweight and passive safety performance. Combining with an A00 model variant, the paper details the design of extruded aluminum-alloy front crossbeam assembly from the perspectives of optimal design, performance verifi- cation, lightweight effect and cost control. The following results in the technical and engineering applications have been achieved. The weight of the developed aluminum-alloy crossbeam can be reduced by 51%. The simulated analysis of the collision rigid wall, the 40 % offset hammering as well as the static crush test of energy-absorbing box show that af- ter reasonable materials matching and size optimization of the crossbeam and the energy-absorbing boxes, the level of crash safety can be improved. The price of aluminum-alloy front crossbeam can be lowered by using the extruding die in- stead of the stamping die to reduce the die cost-sharing.

  8. Advances in very lightweight composite mirror technology

    Science.gov (United States)

    Chen, Peter C.; Bowers, Charles W.; Content, David A.; Marzouk, Marzouk; Romeo, Robert C.

    2000-09-01

    We report progress in the development of very lightweight (roll off and several waves (rms optical) of astigmatism, coma, and third-order spherical aberration. These are indications of thermal contraction in an inhomogeneous medium. This inhomogeneity is due to a systematic radial variation in density and fiber/resin ratio induced in composite plies when draped around a small and highly curved mandrel. The figure accuracy is expected to improve with larger size optics and in mirrors with longer radii of curvature. Nevertheless, the present accuracy figure is sufficient for using postfiguring techniques such as ion milling to achieve diffraction-limited performances at optical and UV wavelengths. We demonstrate active figure control using a simple apparatus of low-mass, low-force actuators to correct astigmatism. The optimized replication technique is applied to the fabrication of a 0.6-m-diam mirror with an areal density of 3.2 kg/m2. Our result demonstrates that the very lightweight, large-aperture construction used in radio telescopes can now be applied to optical telescopes.

  9. FY2014 Lightweight Materials R&D Annual Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-03-01

    The Lightweight Materials research and development (R&D) area within the DOE Vehicle Technologies Office (VTO) provides support and guidance for many cutting-edge automotive technologies under development. Research focuses on addressing critical barriers to commercializing lightweight materials for passenger and commercial vehicles.

  10. Adaptive Backstepping Control of Lightweight Tower Wind Turbine

    DEFF Research Database (Denmark)

    Galeazzi, Roberto; Borup, Kasper Trolle; Niemann, Hans Henrik;

    2015-01-01

    This paper investigates the feasibility of operating a wind turbine with lightweight tower in the full load region exploiting an adaptive nonlinear controller that allows the turbine to dynamically lean against the wind while maintaining nominal power output. The use of lightweight structures...

  11. Anchorage of Main Reinforcement in Lightweight Aggregate Concrete Beams

    DEFF Research Database (Denmark)

    Larsen, Henning

    1999-01-01

    The paper deals with the anchorage of reinforcement bars at end supports in beam component made of lightweight aggregate concrete with open structure.......The paper deals with the anchorage of reinforcement bars at end supports in beam component made of lightweight aggregate concrete with open structure....

  12. Uncertainty and Variation of Vibration in Lightweight Structures

    DEFF Research Database (Denmark)

    Dickow, Kristoffer Ahrens

    2012-01-01

    Multi-family dwellings and offices build from lightweight materials are becoming a cost efficient and environmentally friendly alternative to traditional heavy structures.......Multi-family dwellings and offices build from lightweight materials are becoming a cost efficient and environmentally friendly alternative to traditional heavy structures....

  13. Adaptive Backstepping Control of Lightweight Tower Wind Turbine

    DEFF Research Database (Denmark)

    Galeazzi, Roberto; Borup, Kasper Trolle; Niemann, Hans Henrik

    2015-01-01

    This paper investigates the feasibility of operating a wind turbine with lightweight tower in the full load region exploiting an adaptive nonlinear controller that allows the turbine to dynamically lean against the wind while maintaining nominal power output. The use of lightweight structures for...

  14. 46 CFR 30.10-38 - Lightweight-TB/ALL.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Lightweight-TB/ALL. 30.10-38 Section 30.10-38 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS GENERAL PROVISIONS Definitions § 30.10-38 Lightweight—TB/ALL. The term lightweight means the displacement of a vessel in metric tons without cargo, oil...

  15. Lightweight Concrete Produced Using a Two-Stage Casting Process

    Directory of Open Access Journals (Sweden)

    Jin Young Yoon

    2015-03-01

    Full Text Available The type of lightweight aggregate and its volume fraction in a mix determine the density of lightweight concrete. Minimizing the density obviously requires a higher volume fraction, but this usually causes aggregates segregation in a conventional mixing process. This paper proposes a two-stage casting process to produce a lightweight concrete. This process involves placing lightweight aggregates in a frame and then filling in the remaining interstitial voids with cementitious grout. The casting process results in the lowest density of lightweight concrete, which consequently has low compressive strength. The irregularly shaped aggregates compensate for the weak point in terms of strength while the round-shape aggregates provide a strength of 20 MPa. Therefore, the proposed casting process can be applied for manufacturing non-structural elements and structural composites requiring a very low density and a strength of at most 20 MPa.

  16. Lightweight design for servo frame based on lattice material

    Science.gov (United States)

    Jin, Xin; Li, Guoxi; Liu, Encai; Gong, Jingzhong

    2017-06-01

    Lattice material infilling is an important way to achieve lightweight. Focusing on the problems of non-uniform arrangement and the finite element analysis (FEA) of lattice material in the parts, a lightweight design method based on lattice material is proposed with the spacecraft servo frame as the design object. Modal analysis and topology optimization are carried out according to the boundary conditions. The optimized density results are used to guide the design of lattice material parameters and arrangement. The equivalent mechanical properties of lattice material are obtained through the standard specimens experiments. The equivalent material FEA model of the lightweight servo frame is established, and the performance of the lightweight structure is tested by FEA simulation and experiment. The results show that under the impact condition, the lightweight servo frame meets the performance requirements and the simulation method through the equivalent material model is validated.

  17. Experimental assessment and model development of FRP sandwich panels subjected to out-of-plane impact loading

    NARCIS (Netherlands)

    Schipperen, J.H.A.

    2015-01-01

    Fibre reinforced composites are lightweight, strong materials that are increasingly used in all sorts of applications. When loaded in-plane, the material is very strong due to the profitable properties of the fibres. Therefore, the design is normally such that the predominant loading condition is

  18. Experimental assessment and model development of FRP sandwich panels subjected to out-of-plane impact loading

    NARCIS (Netherlands)

    Schipperen, J.H.A.

    2015-01-01

    Fibre reinforced composites are lightweight, strong materials that are increasingly used in all sorts of applications. When loaded in-plane, the material is very strong due to the profitable properties of the fibres. Therefore, the design is normally such that the predominant loading condition is in

  19. SNAP focal plane

    Energy Technology Data Exchange (ETDEWEB)

    Lampton, Michael L.; Kim, A.; Akerlof, C.W.; Aldering, G.; Amanullah, R.; Astier, P.; Barrelet, E.; Bebek, C.; Bergstrom, L.; Berkovitz, J.; Bernstein, G.; Bester, M.; Bonissent, A.; Bower, C.; Carithers Jr., W.C.; Commins, E.D.; Day, C.; Deustua, S.E.; DiGennaro,R.; Ealet, A.; Ellis, R.S.; Eriksson, M.; Fruchter, A.; Genat, J.-F.; Goldhaber, G.; Goobar, A.; Groom, D.; Harris, S.E.; Harvey, P.R.; Heetderks, H.D.; Holland, S.E.; Huterer, D.; Karcher, A.; Kolbe, W.; Krieger, B.; Lafever, R.; Lamoureux, J.; Levi, M.E.; Levin, D.S.; Linder,E.V.; Loken, S.C.; Malina, R.; Massey, R.; McKay, T.; McKee, S.P.; Miquel, R.; Mortsell, E.; Mostek, N.; Mufson, S.; Musser, J.; Nugent, P.; Oluseyi, H.; Pain, R.; Palaio, N.; Pankow, D.; Perlmutter, S.; Pratt, R.; Prieto, E.; Refregier, A.; Rhodes, J.; Robinson, K.; Roe, N.; Sholl, M.; Schubnell, M.; Smadja, G.; Smoot, G.; Spadafora, A.; Tarle, G.; Tomasch,A.; von der Lippe, H.; Vincent, R.; Walder, J.-P.; Wang, G.

    2002-07-29

    The proposed SuperNova/Acceleration Probe (SNAP) mission will have a two-meter class telescope delivering diffraction-limited images to an instrumented 0.7 square-degree field sensitive in the visible and near-infrared wavelength regime. We describe the requirements for the instrument suite and the evolution of the focal plane design to the present concept in which all the instrumentation--visible and near-infrared imagers, spectrograph, and star guiders--share one common focal plane.

  20. In-plane strain capability of cellulose EAPap material

    Science.gov (United States)

    Kim, Jaehwan; Jung, Woochul; Kang, Yukeun; Jang, Sang-Dong

    2006-03-01

    Electro-Active Paper (EAPap) has been interested in due to its merits in terms of lightweight, dry condition, large displacement output, low actuation voltage, low power consumption and biodegradability. EAPap actuator has been made with cellulose material. Cellulose fibers are dissolved into a solution and extruded in a sheet form, and thin gold electrodes are made on it. This out-of-plane bending deformation is useful for achieving flapping wings, micro-insect robots, and smart wall papers. On the other hand, in-plane strains, such as extension and contraction of EAPap materials are also promising for artificial muscle applications since the Young's modulus of EAPap materials is large. Therefore, we intended to investigate the in-plane strain of EAPap materials in the presence of electric fields. The EAPap samples preparation and the in-plane strain measurement are explained. The test results are shown in terms of electric field, frequency and the orientation of the samples. The power consumption and the strain energy of EAPap samples are discussed. Although there are still unknown facts in EAPap materials, this in-plane strain may be useful for artificial muscle applications.

  1. Beamlet focal plane diagnostic

    Energy Technology Data Exchange (ETDEWEB)

    Caird, J.A.; Nielsen, N.D.; Patton, H.G.; Seppala, L.G.; Thompson, C.E.; Wegner, P.J.

    1996-12-01

    This paper describes the major optical and mechanical design features of the Beamlet Focal Plane Diagnostic system as well as measurements of the system performance, and typical data obtained to date. We also discuss the NIF requirements on the focal spot that we are interested in measuring, and some of our plans for future work using this system.

  2. Advanced casting technologies for lightweight automotive applications

    Directory of Open Access Journals (Sweden)

    Alan A. Luo

    2010-11-01

    Full Text Available This paper provides an overview of alloy and process developments in aluminum and magnesium castings for lightweight automotive applications. Wear-resistant aluminum alloys, creep-resistant and high strength/ductility magnesium alloys have been developed for automotive applications. On the process front, vacuum-assisted die casting and high vacuum die casting technologies have been developed for high-integrity body and chassis applications. Thin-wall and hollow casting components are being produced by low-pressure die casting processes for structural applications. Overcasting technology is gaining traction and has enabled mixed material designs for automotive sub-systems such as engine cradles and instrument panel beams. Simulation tools developed to predict the interfacial interactions of the dissimilar components and the structural integrity of the overcast systems are being validated in the casting trials.

  3. Performance of a New Lightweight Reciprocating Pump

    Energy Technology Data Exchange (ETDEWEB)

    Whitehead, J C

    2005-06-09

    A new four-chamber piston pump design has been fabricated and tested. The small-scale propellant pump is intended to be powered by gas at elevated temperatures, e.g. in a gas-generator cycle rocket propulsion system. Two key features are combined for the first time: leak-tight liquid-cooled seals, and a high throughput per unit hardware mass. Measured performance curves quantify flows, pressures, leakage, volumetric efficiency, and tank pressure requirements. A pair of 300-gram pumps operating with significant margin could deliver fuel and oxidizer at 5 MPa to a compact lightweight 1000-N engine, while tank pressure remains at 0.35 MPa. Pump weight is well below one percent of thrust, as is typical for launch vehicle engines. Applications include small upper stages, aggressive maneuvers in space, and miniature launch vehicles for Mars ascent.

  4. Lightweight, low-cost solar energy collector

    Science.gov (United States)

    Hochberg, Eric B. (Inventor); Costen, Michael K. (Inventor)

    2006-01-01

    A lightweight solar concentrator of the reflecting parabolic or trough type is realized via a thin reflecting film, an inflatable structural housing and tensioned fibers. The reflector element itself is a thin, flexible, specularly-reflecting sheet or film. The film is maintained in the parabolic trough shape by means of a plurality of identical tensioned fibers arranged to be parallel to the longitudinal axis of the parabola. Fiber ends are terminated in two identical spaced anchorplates, each containing a plurality of holes which lie on the desired parabolic contour. In a preferred embodiment, these fibers are arrayed in pairs with one fiber contacting the front side of the reflecting film and the other contacting the back side of the reflecting film. The reflective surface is thereby slidably captured between arrays of fibers which control the shape and position of the reflective film. Gas pressure in the inflatable housing generates fiber tension to achieve a truer parabolic shape.

  5. Utilization of Bamboo as Lightweight Sandwich Panels

    Directory of Open Access Journals (Sweden)

    Suthon SRIVARO

    2016-05-01

    Full Text Available Lightweight sandwich panels consisting of bamboo faces and oil palm trunk core were manufactured using melamine urea formaldehyde with the resin content of 250 g/m2 (solid basis. The parameters examined were node and density of bamboo faces. Physical (board density, thickness swelling and water absorption and mechanical (modulus of elasticity and modulus of rupture properties of the sandwich board obtained were investigated and compared with other bamboo products and commercial wood based products. Result showed that this panel had better dimensional stability than those of other bamboo products but lower bending strength. Node of bamboo had no significant effect on any board properties examined. Most of board properties were influenced by bamboo face density. Comparing the properties to commercial wood based products, this panel could be used as wall/floor applications.

  6. Development of a lightweight fuel cell vehicle

    Science.gov (United States)

    Hwang, J. J.; Wang, D. Y.; Shih, N. C.

    This paper described the development of a fuel cell system and its integration into the lightweight vehicle known as the Mingdao hydrogen vehicle (MHV). The fuel cell system consists of a 5-kW proton exchange membrane fuel cell (PEMFC), a microcontroller and other supported components like a compressed hydrogen cylinder, blower, solenoid valve, pressure regulator, water pump, heat exchanger and sensors. The fuel cell not only propels the vehicle but also powers the supporting components. The MHV performs satisfactorily over a hundred-kilometer drive thus validating the concept of a fuel cell powered zero-emission vehicle. Measurements further show that the fuel cell system has an efficiency of over 30% at the power consumption for vehicle cruise, which is higher than that of a typical internal combustion engine. Tests to improve performance such as speed enhancement, acceleration and fuel efficiency will be conducted in the future work. Such tests will consist of hybridizing with a battery pack.

  7. Utilization of Bamboo as Lightweight Sandwich Panels

    Directory of Open Access Journals (Sweden)

    Suthon SRIVARO

    2016-05-01

    Full Text Available Lightweight sandwich panels consisting of bamboo faces and oil palm trunk core were manufactured using melamine urea formaldehyde with the resin content of 250 g/m2 (solid basis. The parameters examined were node and density of bamboo faces. Physical (board density, thickness swelling and water absorption and mechanical (modulus of elasticity and modulus of rupture properties of the sandwich board obtained were investigated and compared with other bamboo products and commercial wood based products. Result showed that this panel had better dimensional stability than those of other bamboo products but lower bending strength. Node of bamboo had no significant effect on any board properties examined. Most of board properties were influenced by bamboo face density. Comparing the properties to commercial wood based products, this panel could be used as wall/floor applications.

  8. Lightweight ceramic filter components: Evaluation and application

    Energy Technology Data Exchange (ETDEWEB)

    Eggerstedt, P.M.

    1995-11-01

    Ceramic candle filtration is an attractive technology for particulate removal at high temperatures. The primary objective of this SBIR research program is to increase the performance, durability, and corrosion resistance of lightweight filter candles and filter tubesheet components (Fibrosic{trademark}), fabricated from vacuum formed chopped ceramic fiber (VFCCF), for use in advanced coal utilization applications. Phase 1 results proved that significant gains in material strength and particle retentivity are possible by treatment of VFCCF materials with colloidal ceramic oxides. Phase 2 effort will show how these treated materials tolerate high temperature and vapor-phase alkali species, on a long-term basis. With good durability and corrosion resistance, high temperature capability, and a low installed and replacement cost, these novel materials will help promote commercial acceptance of ceramic candle filter technology, as well as increase the efficiency and reliability of coal utilization processes in general.

  9. Lightweight MIPv6 with IPSec Support

    Directory of Open Access Journals (Sweden)

    Antonio J. Jara

    2014-01-01

    Full Text Available Mobility management is a desired feature for the emerging Internet of Things (IoT. Mobility aware solutions increase the connectivity and enhance adaptability to changes of the location and infrastructure. IoT is enabling a new generation of dynamic ecosystems in environments such as smart cities and hospitals. Dynamic ecosystems require ubiquitous access to Internet, seamless handover, flexible roaming policies, and an interoperable mobility protocol with existing Internet infrastructure. These features are challenges for IoT devices, which are usually constrained devices with low memory, processing, communication and energy capabilities. This work presents an analysis of the requirements and desirable features for the mobility support in the IoT, and proposes an efficient solution for constrained environments based on Mobile IPv6 and IPSec. Compatibility with IPv6-existing protocols has been considered a major requirement in order to offer scalable and inter-domain solutions that were not limited to specific application domains in order to enable a new generation of application and services over Internet-enabled dynamic ecosystems, and security support based on IPSec has been also considered, since dynamic ecosystems present several challenges in terms of security and privacy. This work has, on the one hand, analysed suitability of Mobile IPv6 and IPSec for constrained devices, and on the other hand, analysed, designed, developed and evaluated a lightweight version of Mobile IPv6 and IPSec. The proposed solution of lightweight Mobile IPv6 with IPSec is aware of the requirements of the IoT and presents the best solution for dynamic ecosystems in terms of efficiency and security adapted to IoT-devices capabilities. This presents concerns in terms of higher overhead and memory requirements. But, it is proofed and concluded that even when higher memory is required and major overhead is presented, the integration of Mobile IPv6 and IPSec for

  10. Vehicular hydrogen storage using lightweight tanks

    Energy Technology Data Exchange (ETDEWEB)

    Mitlitsky, F; Weisberg, A H; Myers, B

    2000-07-22

    Lightweight hydrogen storage for vehicles is enabled by adopting and adapting aerospace tankage technology. The weight, volume, and cost are already acceptable and improving. Prototype tankage was demonstrated with 11.3% hydrogen by weight, 1.74 million inch (44.3 km) burst performance factor (P{sub b}V/W), and 3.77 kWh/kg specific energy for the tank and hydrogen (LHV). DOE cannot afford full scale aerospace development costs. For example, it costs many tens of $M to develop a rocket motor casing with a safety factor (SF) of 1.25. Large teams of experts are required to design, develop, and test new processes. Car companies are buying existing technology with only modest investments in research and development (R&D). The Lawrence Livermore National Laboratory (LLNL) team is maximizing the leverage from DOE funding by joining with industry to solve technical risks at the component level. LLNL is developing fabrication processes with IMPCO Technologies, Thiokol Propulsion, and Aero Tec Laboratories (ATL). LLNL is creating commercial products that are close to adoption under DOE solicitation. LLNL is breaking ground to achieve greater than 10% hydrogen by weight tankage with safety that exceeds the requirements of NGV2 standards modified for hydrogen. Risk reduction is proceeding along three axes: (1) Commercializable products will be available next year with {approx}90% confidence; (2) R&D progress is pushing the envelope in lightweight tankage for vehicles; and (3) Integration challenges are being met with partners in industry and DOE demo programs. This project is a key part of LLNL's effort to develop high cycle life energy storage systems with >600 Wh/kg specific energy for various applications, including: high altitude long endurance solar rechargeable aircraft, zero emission vehicles, hybrid energy storage/propulsion systems for spacecraft, energy storage for premium power, remote power sources, and peak shaving.

  11. Lightweight males of Podisus nigrispinus (Heteroptera: Pentatomidae neglect lightweight females due low reproductive fitness

    Directory of Open Access Journals (Sweden)

    A. I. A. Pereira

    Full Text Available Abstract Sexual choice by male stink bugs is important because females that experience food shortages lay fewer eggs with lower viability compared with well-fed females. In this study, we investigated whether Podisus nigrispinus (Dallas (Heteroptera: Pentatomidae males fed with a low-quality diet during its nymphal stage show selectivity for sexual partners resulting in high-quality progeny. Lightweight males and females were obtained from nymphs fed weekly with Tenebrio molitor L. (Coleoptera: Tenebrionidae pupae. By contrast, heavyweight males and females were fed three times a week and received an extra nutritional source: cotton leaves, Gossypium hirsutum L. (Malvaceae. Lightweight males preferred to mate with heavy females (77.78 ± 14.69%, whereas heavyweight males did not discriminated between light or heavyweight females. Females mated with lightweight males showed similar levels of reproduction to those mated with heavyweight males. The results provide an indication of the importance of male and female body weight for sexual selection in Asopinae stink bugs.

  12. Vehicle Lightweighting: Mass Reduction Spectrum Analysis and Process Cost Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Mascarin, Anthony [IBIS Associates, Inc., Waltham, MA (United States); Hannibal, Ted [IBIS Associates, Inc., Waltham, MA (United States); Raghunathan, Anand [Energetics Inc., Columbia, MD (United States); Ivanic, Ziga [Energetics Inc., Columbia, MD (United States); Clark, Michael [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-03-01

    The U.S. Department of Energy’s Vehicle Technologies Office, Materials area commissioned a study to model and assess manufacturing economics of alternative design and production strategies for a series of lightweight vehicle concepts. In the first two phases of this effort examined combinations of strategies aimed at achieving strategic targets of 40% and a 45% mass reduction relative to a standard North American midsize passenger sedan at an effective cost of $3.42 per pound (lb) saved. These results have been reported in the Idaho National Laboratory report INL/EXT-14-33863 entitled Vehicle Lightweighting: 40% and 45% Weight Savings Analysis: Technical Cost Modeling for Vehicle Lightweighting published in March 2015. The data for these strategies were drawn from many sources, including Lotus Engineering Limited and FEV, Inc. lightweighting studies, U.S. Department of Energy-funded Vehma International of America, Inc./Ford Motor Company Multi-Material Lightweight Prototype Vehicle Demonstration Project, the Aluminum Association Transportation Group, many United States Council for Automotive Research’s/United States Automotive Materials Partnership LLC lightweight materials programs, and IBIS Associates, Inc.’s decades of experience in automotive lightweighting and materials substitution analyses.

  13. Security Isolation Strategy Mechanism for Lightweight Virtualization Environment

    Directory of Open Access Journals (Sweden)

    Liu Qian

    2017-01-01

    Full Text Available For cloud service providers, lightweight virtualization is a more economical way of virtualization. While the user is worried about the safety of applications and data of the container, due to the container sharing the underlying interface and the kernel, therefore the security and trusted degree of lightweight virtualization container isolation mechanism is critical for the promotion of lightweight virtualization service. Because the user cannot directly participate in the process of the construction and management of container isolation mechanism, it is difficult for them to establish confidence in the security and trusted degree of container isolation mechanism. Based on the research and analysis of system credible and virtualization isolation mechanism, this paper puts forward a set of lightweight virtualization security isolation strategy mechanism, divides lightweight virtualization container storage address space into several parts, puts forward the definition of lightweight virtualization security isolation, gives the formal description and proof of container security isolation strategy, and combines with related technology to verify the feasibility of lightweight virtualization security isolation strategy mechanism. The mechanism has important guiding significance for cloud services providers to deploy container security isolation.

  14. Effect of lightweight aggregate intrinsic Strength on lightweight concrete compressive strength and modulus of elasticity

    Directory of Open Access Journals (Sweden)

    Videla, C.

    2002-03-01

    Full Text Available The study of Structural Lightweight Concrete (SLC, which is a material generally composed of cement, water and lightweight aggregate, has been mainly focused on developing particular cases. Then, the main objective of this research was to generalise the knowledge of this type of material. Particularly, the effect of replacing conventional coarse aggregate by lightweight aggregate on mechanical properties of concrete was studied. SLC may be conceived as a two -phase material. The first phase, composed of cement, water and siliceous natural sand, is called the "resistant phase", and contributes to the structural strength. The second phase is the lightweight phase, comprised of coarse lightweight aggregate, and it is meant to decrease the concrete density. In this way it would be possible to describe the mechanical behaviour of concrete, based on lightweight aggregate and the cement mortar parameters. The obtained results allow for the proposition of relationships between mechanical properties of SLC (such as compressive strength and modulus of elasticity and the constituent materials properties and amount. At the same time, an easily measured index representing the structural capability of lightweight aggregate is also proposed, this index allows to estimate the potential mechanical properties of concrete which could be obtained by using a particular aggregate.

    El estudio del Hormigón Ligero Estructural (HLE, material compuesto generalmente por cemento, agua y árido ligero, ha estado enfocado principalmente al desarrollo de casos particulares. Por lo anterior, el objetivo principal de esta investigación fue generalizar el conocimiento sobre este material. En particular, la meta de este trabajo fue estudiar el efecto que tiene el reemplazo de árido convencional por un árido ligero, en las propiedades mecánicas del hormigón. El modelo aplicado conceptualiza al HLE como un material de dos fases, una denominada "soportante", constituida

  15. Integrated Control with Structural Feedback to Enable Lightweight Aircraft

    Science.gov (United States)

    Taylor, Brian R.

    2011-01-01

    This presentation for the Fundamental Aeronautics Program Technical Conference covers the benefits of active structural control, related research areas, and focuses on the use of optimal control allocation for the prevention of critical loads. Active control of lightweight structures has the potential to reduce aircraft weight and fuel burn. Sensor, control law, materials, control effector, and system level research will be necessary to enable active control of lightweight structures. Optimal control allocation with structural feedback has been shown in simulation to be feasible in preventing critical loads and is one example of a control law to enable future lightweight aircraft.

  16. Lightweight Phase-Change Material For Solar Power

    Science.gov (United States)

    Stark, Philip

    1993-01-01

    Lightweight panels containing phase-change materials developed for use as heat-storage elements of compact, lightweight, advanced solar dynamic power system. During high insolation, heat stored in panels via latent heat of fusion of phase-change material; during low insolation, heat withdrawn from panels. Storage elements consist mainly of porous carbon-fiber structures imbued with germanium. Developed for use aboard space station in orbit around Earth, also adapted to lightweight, compact, portable solar-power systems for use on Earth.

  17. Boundaries in digital planes

    Directory of Open Access Journals (Sweden)

    Efim Khalimsky

    1990-01-01

    Full Text Available The importance of topological connectedness properties in processing digital pictures is well known. A natural way to begin a theory for this is to give a definition of connectedness for subsets of a digital plane which allows one to prove a Jordan curve theorem. The generally accepted approach to this has been a non-topological Jordan curve theorem which requires two different definitions, 4-connectedness, and 8-connectedness, one for the curve and the other for its complement.

  18. BKP plane partitions

    Energy Technology Data Exchange (ETDEWEB)

    Foda, Omar; Wheeler, Michael [Department of Mathematics and Statistics, University of Melbourne, Parkville, Victoria 3010 (Australia)

    2007-01-15

    Using BKP neutral fermions, we derive a product expression for the generating function of volume-weighted plane partitions that satisfy two conditions. If we call a set of adjacent equal height-h columns, h > 0, an h-path, then 1. Every h-path can assume one of two possible colours. 2. There is a unique way to move along an h-path from any column to another.

  19. Lightweight, Self-Deploying Foam Antenna Structures

    Science.gov (United States)

    Sokolowski, Witold; Levin, Steven; Rand, Peter

    2004-01-01

    Lightweight, deployable antennas for a variety of outer-space and terrestrial applications would be designed and fabricated according to the concept of cold hibernated elastic memory (CHEM) structures, according to a proposal. Mechanically deployable antennas now in use are heavy, complex, and unreliable, and they utilize packaging volume inefficiently. The proposed CHEM antenna structures would be simple and would deploy themselves without need for any mechanisms and, therefore, would be more reliable. The proposed CHEM antenna structures would also weigh less, could be packaged in smaller volumes, and would cost less, relative to mechanically deployable antennas. The CHEM concept was described in two prior NASA Tech Briefs articles: "Cold Hibernated Elastic Memory (CHEM) Expandable Structures" (NPO-20394), Vol. 23, No. 2 (February 1999), page 56; and "Solar Heating for Deployment of Foam Structures" (NPO-20961), Vol. 25, No. 10 (October 2001), page 36. To recapitulate from the cited prior articles: The CHEM concept is one of utilizing opencell foams of shape-memory polymers (SMPs) to make lightweight, reliable, simple, and inexpensive structures that can be alternately (1) compressed and stowed compactly or (2) expanded, then rigidified for use. A CHEM structure is fabricated at full size from a block of SMP foam in its glassy state [at a temperature below the glass-transition temperature (Tg) of the SMP]. The structure is heated to the rubbery state of the SMP (that is, to a temperature above Tg) and compacted to a small volume. After compaction, the structure is cooled to the glassy state of the SMP. The compacting force can then be released and the structure remains compact as long as the temperature is kept below Tg. Upon subsequent heating of the structure above Tg, the simultaneous elastic recovery of the foam and its shape-memory effect cause the structure to expand to its original size and shape. Once thus deployed, the structure can be rigidified by

  20. Ultra-Lightweight Large Aperture Support Structures Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Ultra-lightweight membranes may prove to be very attractive for large aperture systems, but their value will be fully realized only if they are mated with equally...

  1. Lightweight Metal RubberTM Sensors and Interconnects Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of the proposed program is to develop lightweight and highly elastic electrically conducting interconnects and strain sensor arrays for next generation...

  2. study of the strength characteristics of protein-based lightweight ...

    African Journals Online (AJOL)

    user

    Compressive strength test was carried out on the protein-based lightweight foamed concrete produced ... 150 mm were produced using ordinary Portland cement (OPC), fine aggregate, ..... values obtained for the loss on ignition (LOI) and SO3.

  3. Low Cost, Lightweight, Multifunctional Structural Shielding Materials Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR involves the development of a lightweight innovative material for use as structure and radiation shielding in one. APS has assembled a uniquely qualified...

  4. Lightweight IMM Multi-Junction Photovoltaic Flexible Blanket Assembly Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Deployable Space Systems (DSS) and EMCORE as a key subcontractor will focus the proposed SBIR program on the creation and optimization of a lightweight ~33%...

  5. Lightweight InP Solar Cells for Space Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation in this Phase II SBIR is the development of a technology which will enable the manufacture of a lightweight, low cost, high radiation resistance InP...

  6. Next Generation MK III Lightweight HUT/Hatch Assembly Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A prototype Next Generation MK III Lightweight HUT/Hatch Assembly will be fabricated and delivered during Phase II. Maximum weight reduction for the Hard Upper...

  7. Next Generation MK III Lightweight HUT/Hatch Assembly Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Next Generation MK III Lightweight HUT/Hatch Assembly will maximize the Hard Upper Torso - Hatch assembly weight reduction through the combination of innovative...

  8. Lightweight landscape enhancing design through minimal mass structures

    CERN Document Server

    Spinelli, Luigi; Monticelli, Carol; Pedrali, Paolo

    2016-01-01

    This book explains how lightweight materials and structures can be deployed in buildings to meet high environmental and aesthetic standards and emphasizes how the concept of lightness in building technology and design dovetails with the desire to enhance landscape. The first part of the book, on lightweight construction, aims to foster the use of membranes within the specific climatic context and in particular considers how lightweight materials and innovative technologies can enrich the quality of temporary spaces. The second part focuses exclusively on landscape, presenting novel approaches in the search for visual lightness and the quest to improve urban spaces. Particular attention is paid to the Italian experience, where the traditional appreciation of brick and stone has limited the scope for use of lightweight structures and membrane materials, often relegating them to a secondary or inappropriate role. The reader will come to appreciate how this attitude demeans a very advanced productive sector and n...

  9. Lightweight InP Solar Cells for Space Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation in this Phase I SBIR is the development of a technology which will enable the manufacture of a lightweight, low cost, InP based compound semiconductor...

  10. Study on Performance and Processability of Sirofil Lightweight Worsted Fabric

    Institute of Scientific and Technical Information of China (English)

    李明菊; 范德炘; 葛惠萍; 侯祖龄

    2001-01-01

    The lightweight worsted fabric made of Sirofil yarn was developed and its textile performance was studied. By means of conventional testing, KES and FAST, it is concluded that with the coordination of proper fabric design and processing technique, the performance of this innovative fabric is superior to that of the conventional lightweight fabric Furthermore, it is predicted from the relevant parameters that its processability in the following suit manufacture is very desirable.

  11. Lightweight Aggregate Concrete Beams. Load-bearing Capacity

    DEFF Research Database (Denmark)

    Larsen, Henning; Goltermann, Per; Ingholt, N.U.

    1997-01-01

    This paper deals with the load-bearing capacity of reinforced beams made of lightweight aggregate concrete with open structure and documents formulas for the moment capacity as well as the shear force capacity.......This paper deals with the load-bearing capacity of reinforced beams made of lightweight aggregate concrete with open structure and documents formulas for the moment capacity as well as the shear force capacity....

  12. Lightweight Aggregate Concrete Components. Load-bearing Capacity

    DEFF Research Database (Denmark)

    Larsen, Henning; Ingholt, N.U.; Goltermann, Per

    1996-01-01

    The project presented here deals with the load-bearing capacity of reinforced beams made of lightweight aggregate concrete with open structure and documents expressions for the moment capacity as well as the shear force capacity......The project presented here deals with the load-bearing capacity of reinforced beams made of lightweight aggregate concrete with open structure and documents expressions for the moment capacity as well as the shear force capacity...

  13. Lightweight Absorption and Barrier Systems Comprising N-Layer Microperforates

    OpenAIRE

    Kim, Nicholas N; Bolton, J. Stuart

    2017-01-01

    Since the concept of microperforated panels (MPPs) was introduced by Maa, there have been continuing efforts to apply MPPs, primarily as fiber-free sound absorbing materials, typically wall-mounted. The objective of the present work was to demonstrate that multi-layer MPPs can also be effective functional absorbers and lightweight barrier systems. The acoustical properties of lightweight MPPs depend on hole diameter, thickness, porosity, mass per unit area, and air cavity depth. In the case o...

  14. Sound transmission through finite lightweight multilayered structures with thin air layers.

    Science.gov (United States)

    Dijckmans, A; Vermeir, G; Lauriks, W

    2010-12-01

    The sound transmission loss (STL) of finite lightweight multilayered structures with thin air layers is studied in this paper. Two types of models are used to describe the vibro-acoustic behavior of these structures. Standard transfer matrix method assumes infinite layers and represents the plane wave propagation in the layers. A wave based model describes the direct sound transmission through a rectangular structure placed between two reverberant rooms. Full vibro-acoustic coupling between rooms, plates, and air cavities is taken into account. Comparison with double glazing measurements shows that this effect of vibro-acoustic coupling is important in lightweight double walls. For infinite structures, structural damping has no significant influence on STL below the coincidence frequency. In this frequency region, the non-resonant transmission or so-called mass-law behavior dominates sound transmission. Modal simulations suggest a large influence of structural damping on STL. This is confirmed by experiments with double fiberboard partitions and sandwich structures. The results show that for thin air layers, the damping induced by friction and viscous effects at the air gap surfaces can largely influence and improve the sound transmission characteristics.

  15. UTILIZATION OF LIGHTWEIGHT MATERIALS MADE FROM COAL GASIFICATION SLAGS

    Energy Technology Data Exchange (ETDEWEB)

    Vas Choudhry; Stephen Kwan; Steven R. Hadley

    2001-07-01

    The objective of the project entitled ''Utilization of Lightweight Materials Made from Coal Gasification Slags'' was to demonstrate the technical and economic viability of manufacturing low-unit-weight products from coal gasification slags which can be used as substitutes for conventional lightweight and ultra-lightweight aggregates. In Phase I, the technology developed by Praxis to produce lightweight aggregates from slag (termed SLA) was applied to produce a large batch (10 tons) of expanded slag using pilot direct-fired rotary kilns and a fluidized bed calciner. The expanded products were characterized using basic characterization and application-oriented tests. Phase II involved the demonstration and evaluation of the use of expanded slag aggregates to produce a number of end-use applications including lightweight roof tiles, lightweight precast products (e.g., masonry blocks), structural concrete, insulating concrete, loose fill insulation, and as a substitute for expanded perlite and vermiculite in horticultural applications. Prototypes of these end-use applications were made and tested with the assistance of commercial manufacturers. Finally, the economics of expanded slag production was determined and compared with the alternative of slag disposal. Production of value-added products from SLA has a significant potential to enhance the overall gasification process economics, especially when the avoided costs of disposal are considered.

  16. Advanced steel body concepts for automotive lightweight design

    Energy Technology Data Exchange (ETDEWEB)

    Herrmann, H.G. [DaimlerChrysler AG, Stuttgart (Germany). Research Body and Powertrain

    2005-07-01

    Lightweight design is a must for future vehicle concepts due to the self-commitment on the reduction of fleet consumption. Body concepts for mid- and high-volume vehicles demand smart lightweight solutions without increasing costs and without sacrificing the high level of safety (e.g. future passive safety standards). Furthermore, all lightweight activities have to comply with requirements in terms of reliability (no additional efforts for maintenance), NVH (no additional weight for e.g. damping) and future stricter recycling quotas. Successful lightweight design solutions are determined by the best relation between weight-saving and additional costs as a function of the annual production volume. Using advanced high-strength steels (TWIP-steels) seems to be a very promising approach for cost-optimized lightweight design of body structures. In addition, by applying bionic optimization, the weight of body-structures can be significantly reduced. As a consequence, only a holistic approach for lightweight design combining the three areas materials, design and manufacturing is needed in order to use the full potential of cost-optimized weight-reduction. (orig.)

  17. Lightweight, highly compressible, noncrystalline cellulose capsules.

    Science.gov (United States)

    Carrick, Christopher; Lindström, Stefan B; Larsson, Per Tomas; Wågberg, Lars

    2014-07-08

    We demonstrate how to prepare extraordinarily deformable, gas-filled, spherical capsules from nonmodified cellulose. These capsules have a low nominal density, ranging from 7.6 to 14.2 kg/m(3), and can be deformed elastically to 70% deformation at 50% relative humidity. No compressive strain-at-break could be detected for these dry cellulose capsules, since they did not rupture even when compressed into a disk with pockets of highly compressed air. A quantitative constitutive model for the large deformation compression of these capsules is derived, including their high-frequency mechanical response and their low-frequency force relaxation, where the latter is governed by the gas barrier properties of the dry capsule. Mechanical testing corroborated these models with good accuracy. Force relaxation measurements at a constant compression rendered an estimate for the gas permeability of air through the capsule wall, calculated to 0.4 mL μm/m(2) days kPa at 50% relative humidity. These properties taken together open up a large application area for the capsules, and they could most likely be used for applications in compressible, lightweight materials and also constitute excellent model materials for adsorption and adhesion studies.

  18. Abstracting audit data for lightweight intrusion detection

    KAUST Repository

    Wang, Wei

    2010-01-01

    High speed of processing massive audit data is crucial for an anomaly Intrusion Detection System (IDS) to achieve real-time performance during the detection. Abstracting audit data is a potential solution to improve the efficiency of data processing. In this work, we propose two strategies of data abstraction in order to build a lightweight detection model. The first strategy is exemplar extraction and the second is attribute abstraction. Two clustering algorithms, Affinity Propagation (AP) as well as traditional k-means, are employed to extract the exemplars, and Principal Component Analysis (PCA) is employed to abstract important attributes (a.k.a. features) from the audit data. Real HTTP traffic data collected in our institute as well as KDD 1999 data are used to validate the two strategies of data abstraction. The extensive test results show that the process of exemplar extraction significantly improves the detection efficiency and has a better detection performance than PCA in data abstraction. © 2010 Springer-Verlag.

  19. Lightweight Thermoformed Structural Components and Optics

    Science.gov (United States)

    Zeiders, Glenn W.; Bradford, Larry J.

    2004-01-01

    A technique that involves the use of thermoformed plastics has been developed to enable the design and fabrication of ultra-lightweight structural components and mirrors for use in outer space. The technique could also be used to produce items for special terrestrial uses in which minimization of weight is a primary design consideration. Although the inherent strengths of thermoplastics are clearly inferior to those of metals and composite materials, thermoplastics offer a distinct advantage in that they can be shaped, at elevated temperatures, to replicate surfaces (e.g., prescribed mirror surfaces) precisely. Furthermore, multiple elements can be bonded into structures of homogeneous design that display minimal thermal deformation aside from simple expansion. The design aspect of the present technique is based on the principle that the deflection of a plate that has internal structure depends far more on the overall thickness than on the internal details; thus, a very stiff, light structure can be made from thin plastic that is heatformed to produce a sufficiently high moment of inertia. General examples of such structures include I beams and eggcrates.

  20. Chlorinated drinking water for lightweight laying hens

    Directory of Open Access Journals (Sweden)

    A.F. Schneider

    Full Text Available ABSTRACT The study aimed to evaluate the effect of different levels of chlorine in drinking water of laying hens on zootechnical performance, eggs shell quality, hemogasometry levels and calcium content in tibia. 144 Hy-Line laying hens, 61 weeks old, were used distributed in 24 metabolism cages. They were subjected to water diets, for a period of 28 days, using sodium hypochlorite as a chlorine source in order to obtain the following concentrations: 5ppm (control, 20ppm, 50ppm, and 100ppm. Their performance was evaluated through water consumption, feed intake, egg production and weight, egg mass, feed conversion. Shell quality was measured by specific gravity. At the end of the experiment, arterial blood was collected for blood gas level assessment and a poultry of each replicate was sacrificed to obtain tibia and calcium content measurement. There was a water consumption reduction from 20ppm of chlorine and feed intake reduction in poultry receiving water with 100ppm of chlorine. The regression analysis showed that the higher the level of chlorine in water, the higher the reduction in consumption. There were no differences in egg production and weight, egg mass, feed conversion, specific gravity, tibia calcium content, and hemogasometry levels (hydrogenionic potential, carbon dioxide partial pressure, oxygen partial pressure, sodium, potassium, chloride, bicarbonate, carbon dioxide total concentration, anion gap and oxygen saturation. The use of levels above 5ppm of chlorine is not recommended in the water of lightweight laying hens.

  1. Parallel Array Classes and Lightweight Sharing Mechanisms

    Directory of Open Access Journals (Sweden)

    Steve W. Otto

    1993-01-01

    Full Text Available We discuss a set of parallel array classes, MetaMP, for distributed-memory architectures. The classes are implemented in C++ and interface to the PVM or Intel NX message-passing systems. An array class implements a partitioned array as a set of objects distributed across the nodes – a "collective" object. Object methods hide the low-level message-passing and implement meaningful array operations. These include transparent guard strips (or sharing regions that support finite-difference stencils, reductions and multibroadcasts for support of pivoting and row operations, and interpolation/contraction operations for support of multigrid algorithms. The concept of guard strips is generalized to an object implementation of lightweight sharing mechanisms for finite element method (FEM and particle-in-cell (PIC algorithms. The sharing is accomplished through the mechanism of weak memory coherence and can be efficiently implemented. The price of the efficient implementation is memory usage and the need to explicitly specify the coherence operations. An intriguing feature of this programming model is that it maps well to both distributed-memory and shared-memory architectures.

  2. Lightweight Solar Power for Small Satellites

    Science.gov (United States)

    Nabors, Sammy A.

    2015-01-01

    The innovation targets small satellites or CubeSats for which conventional deployable arrays are not feasible due to their size, weight and complexity. This novel solar cell array includes a thin and flexible photovoltaic cell applied to an inflatable structure to create a high surface area array for collecting solar energy in a lightweight, simple and deployable structure. The inflatable array, with its high functional surface area, eliminates the need and the mechanisms required to point the system toward the sun. The power density achievable in these small arrays is similar to that of conventional high-power deployable/pointable arrays used on large satellites or space vehicles. Although inflatable solar arrays have been previously considered by others, the arrays involved the use of traditional rigid solar cells. Researchers are currently working with thin film photovoltaics from various suppliers so that the NASA innovation is not limited to any particular solar cell technology. NASA has built prototypes and tested functionality before and after inflation. As shown in the current-voltage currents below, deployment does not damage the cell performance.

  3. Novel hyperspectral imager for lightweight UAVs

    Science.gov (United States)

    Saari, Heikki; Aallos, Ville-Veikko; Holmlund, Christer; Mäkynen, Jussi; Delauré, Bavo; Nackaerts, Kris; Michiels, Bart

    2010-04-01

    VTT Technical Research Centre of Finland has developed a new miniaturized staring hyperspectral imager with a weight of 350 g making the system compatible with lightweight UAS platforms. The instrument is able to record 2D spatial images at the selected wavelength bands simultaneously. The concept of the hyperspectral imager has been published in the SPIE Proc. 74741. The operational wavelength range of the imager can be tuned in the range 400 - 1100 nm and spectral resolution is in the range 5 - 10 nm @ FWHM. Presently the spatial resolution is 480 × 750 pixels but it can be increased simply by changing the image sensor. The field of view of the system is 20 × 30 degrees and ground pixel size at 100 m flying altitude is around 7.5 cm. The system contains batteries, image acquisition control system and memory for the image data. It can operate autonomously recording hyperspectral data cubes continuously or controlled by the autopilot system of the UAS. The new hyperspectral imager prototype was first tried in co-operation with the Flemish Institute for Technological Research (VITO) on their UAS helicopter. The instrument was configured for the spectral range 500 - 900 nm selected for the vegetation and natural water monitoring applications. The design of the UAS hyperspectral imager and its characterization results together with the analysis of the spectral data from first test flights will be presented.

  4. Lightweight autonomous chemical identification system (LACIS)

    Science.gov (United States)

    Lozos, George; Lin, Hai; Burch, Timothy

    2012-06-01

    Smiths Detection and Intelligent Optical Systems have developed prototypes for the Lightweight Autonomous Chemical Identification System (LACIS) for the US Department of Homeland Security. LACIS is to be a handheld detection system for Chemical Warfare Agents (CWAs) and Toxic Industrial Chemicals (TICs). LACIS is designed to have a low limit of detection and rapid response time for use by emergency responders and could allow determination of areas having dangerous concentration levels and if protective garments will be required. Procedures for protection of responders from hazardous materials incidents require the use of protective equipment until such time as the hazard can be assessed. Such accurate analysis can accelerate operations and increase effectiveness. LACIS is to be an improved point detector employing novel CBRNE detection modalities that includes a militaryproven ruggedized ion mobility spectrometer (IMS) with an array of electro-resistive sensors to extend the range of chemical threats detected in a single device. It uses a novel sensor data fusion and threat classification architecture to interpret the independent sensor responses and provide robust detection at low levels in complex backgrounds with minimal false alarms. The performance of LACIS prototypes have been characterized in independent third party laboratory tests at the Battelle Memorial Institute (BMI, Columbus, OH) and indoor and outdoor field tests at the Nevada National Security Site (NNSS). LACIS prototypes will be entering operational assessment by key government emergency response groups to determine its capabilities versus requirements.

  5. Testnodes: a Lightweight Node-Testing Infrastructure

    Science.gov (United States)

    Fay, R.; Bland, J.

    2014-06-01

    A key aspect of ensuring optimum cluster reliability and productivity lies in keeping worker nodes in a healthy state. Testnodes is a lightweight node testing solution developed at Liverpool. While Nagios has been used locally for general monitoring of hosts and services, Testnodes is optimised to answer one question: is there any reason this node should not be accepting jobs? This tight focus enables Testnodes to inspect nodes frequently with minimal impact and provide a comprehensive and easily extended check with each inspection. On the server side, Testnodes, implemented in python, interoperates with the Torque batch server to control the nodes production status. Testnodes remotely and in parallel executes client-side test scripts and processes the return codes and output, adjusting the node's online/offline status accordingly to preserve the integrity of the overall batch system. Testnodes reports via log, email and Nagios, allowing a quick overview of node status to be reviewed and specific node issues to be identified and resolved quickly. This presentation will cover testnodes design and implementation, together with the results of its use in production at Liverpool, and future development plans.

  6. Plane and geodetic surveying

    CERN Document Server

    Johnson, Aylmer

    2004-01-01

    Plane and Geodetic Surveying blends theory and practice, conventional techniques and GPS, to provide the ideal book for students of surveying.Detailed guidance is given on how and when the principle surveying instruments (theodolites, Total Stations, levels and GPS) should be used. Concepts and formulae needed to convert instrument readings into useful results are explained. Rigorous explanations of the theoretical aspects of surveying are given, while at the same time a wealth of useful advice about conducting a survey in practice is provided. An accompanying least squares adjustment program

  7. Fourier plane image amplifier

    Science.gov (United States)

    Hackel, L.A.; Hermann, M.R.; Dane, C.B.; Tiszauer, D.H.

    1995-12-12

    A solid state laser is frequency tripled to 0.3 {micro}m. A small portion of the laser is split off and generates a Stokes seed in a low power oscillator. The low power output passes through a mask with the appropriate hole pattern. Meanwhile, the bulk of the laser output is focused into a larger stimulated Brillouin scattering (SBS) amplifier. The low power beam is directed through the same cell in the opposite direction. The majority of the amplification takes place at the focus which is the fourier transform plane of the mask image. The small holes occupy large area at the focus and thus are preferentially amplified. The amplified output is now imaged onto the multichip module where the holes are drilled. Because of the fourier plane amplifier, only about 1/10th the power of a competitive system is needed. This concept allows less expensive masks to be used in the process and requires much less laser power. 1 fig.

  8. The Aerodynamic Plane Table

    Science.gov (United States)

    Zahm, A F

    1924-01-01

    This report gives the description and the use of a specially designed aerodynamic plane table. For the accurate and expeditious geometrical measurement of models in an aerodynamic laboratory, and for miscellaneous truing operations, there is frequent need for a specially equipped plan table. For example, one may have to measure truly to 0.001 inch the offsets of an airfoil at many parts of its surface. Or the offsets of a strut, airship hull, or other carefully formed figure may require exact calipering. Again, a complete airplane model may have to be adjusted for correct incidence at all parts of its surfaces or verified in those parts for conformance to specifications. Such work, if but occasional, may be done on a planing or milling machine; but if frequent, justifies the provision of a special table. For this reason it was found desirable in 1918 to make the table described in this report and to equip it with such gauges and measures as the work should require.

  9. The MOND Fundamental Plane

    CERN Document Server

    Cardone, V F; Diaferio, A; Tortora, C; Molinaro, R

    2010-01-01

    Modified Newtonian Dynamics (MOND) has been shown to be able to fit spiral galaxy rotation curves as well as giving a theoretical foundation for empirically determined scaling relations, such as the Tully - Fisher law, without the need for a dark matter halo. As a complementary analysis, one should investigate whether MOND can also reproduce the dynamics of early - type galaxies (ETGs) without dark matter. As a first step, we here show that MOND can indeed fit the observed central velocity dispersion $\\sigma_0$ of a large sample of ETGs assuming a simple MOND interpolating functions and constant anisotropy. We also show that, under some assumptions on the luminosity dependence of the Sersic n parameter and the stellar M/L ratio, MOND predicts a fundamental plane for ETGs : a log - linear relation among the effective radius $R_{eff}$, $\\sigma_0$ and the mean effective intensity $\\langle I_e \\rangle$. However, we predict a tilt between the observed and the MOND fundamental planes.

  10. Fourier plane image amplifier

    Science.gov (United States)

    Hackel, Lloyd A.; Hermann, Mark R.; Dane, C. Brent; Tiszauer, Detlev H.

    1995-01-01

    A solid state laser is frequency tripled to 0.3 .mu.m. A small portion of the laser is split off and generates a Stokes seed in a low power oscillator. The low power output passes through a mask with the appropriate hole pattern. Meanwhile, the bulk of the laser output is focused into a larger stimulated Brillouin scattering (SBS) amplifier. The low power beam is directed through the same cell in the opposite direction. The majority of the amplification takes place at the focus which is the fourier transform plane of the mask image. The small holes occupy large area at the focus and thus are preferentially amplified. The amplified output is now imaged onto the multichip module where the holes are drilled. Because of the fourier plane amplifier, only .about.1/10th the power of a competitive system is needed. This concept allows less expensive masks to be used in the process and requires much less laser power.

  11. Next Generation Lightweight Mirror Modeling Software

    Science.gov (United States)

    Arnold, William R., Sr.; Fitzgerald, Mathew; Rosa, Rubin Jaca; Stahl, H. Philip

    2013-01-01

    The advances in manufacturing techniques for lightweight mirrors, such as EXELSIS deep core low temperature fusion, Corning's continued improvements in the Frit bonding process and the ability to cast large complex designs, combined with water-jet and conventional diamond machining of glasses and ceramics has created the need for more efficient means of generating finite element models of these structures. Traditional methods of assembling 400,000 + element models can take weeks of effort, severely limiting the range of possible optimization variables. This paper will introduce model generation software developed under NASA sponsorship for the design of both terrestrial and space based mirrors. The software deals with any current mirror manufacturing technique, single substrates, multiple arrays of substrates, as well as the ability to merge submodels into a single large model. The modeler generates both mirror and suspension system elements, suspensions can be created either for each individual petal or the whole mirror. A typical model generation of 250,000 nodes and 450,000 elements only takes 5-10 minutes, much of that time being variable input time. The program can create input decks for ANSYS, ABAQUS and NASTRAN. An archive/retrieval system permits creation of complete trade studies, varying cell size, depth, and petal size, suspension geometry with the ability to recall a particular set of parameters and make small or large changes with ease. The input decks created by the modeler are text files which can be modified by any editor, all the key shell thickness parameters are accessible and comments in deck identify which groups of elements are associated with these parameters. This again makes optimization easier. With ANSYS decks, the nodes representing support attachments are grouped into components; in ABAQUS these are SETS and in NASTRAN as GRIDPOINT SETS, this make integration of these models into large telescope or satellite models easier.

  12. Next-Generation Lightweight Mirror Modeling Software

    Science.gov (United States)

    Arnold, William R., Sr.; Fitzgerald, Mathew; Rosa, Rubin Jaca; Stahl, Phil

    2013-01-01

    The advances in manufacturing techniques for lightweight mirrors, such as EXELSIS deep core low temperature fusion, Corning's continued improvements in the Frit bonding process and the ability to cast large complex designs, combined with water-jet and conventional diamond machining of glasses and ceramics has created the need for more efficient means of generating finite element models of these structures. Traditional methods of assembling 400,000 + element models can take weeks of effort, severely limiting the range of possible optimization variables. This paper will introduce model generation software developed under NASA sponsorship for the design of both terrestrial and space based mirrors. The software deals with any current mirror manufacturing technique, single substrates, multiple arrays of substrates, as well as the ability to merge submodels into a single large model. The modeler generates both mirror and suspension system elements, suspensions can be created either for each individual petal or the whole mirror. A typical model generation of 250,000 nodes and 450,000 elements only takes 5-10 minutes, much of that time being variable input time. The program can create input decks for ANSYS, ABAQUS and NASTRAN. An archive/retrieval system permits creation of complete trade studies, varying cell size, depth, and petal size, suspension geometry with the ability to recall a particular set of parameters and make small or large changes with ease. The input decks created by the modeler are text files which can be modified by any editor, all the key shell thickness parameters are accessible and comments in deck identify which groups of elements are associated with these parameters. This again makes optimization easier. With ANSYS decks, the nodes representing support attachments are grouped into components; in ABAQUS these are SETS and in NASTRAN as GRIDPOINT SETS, this make integration of these models into large telescope or satellite models possible

  13. Lightweight composites for modular panelized construction

    Science.gov (United States)

    Vaidya, Amol S.

    Rapid advances in construction materials technology have enabled civil engineers to achieve impressive gains in the safety, economy, and functionality of structures built to serve the common needs of society. Modular building systems is a fast-growing modern, form of construction gaining recognition for its increased efficiency and ability to apply modern technology to the needs of the market place. In the modular construction technique, a single structural panel can perform a number of functions such as providing thermal insulation, vibration damping, and structural strength. These multifunctional panels can be prefabricated in a manufacturing facility and then transferred to the construction site. A system that uses prefabricated panels for construction is called a "panelized construction system". This study focuses on the development of pre-cast, lightweight, multifunctional sandwich composite panels to be used for panelized construction. Two thermoplastic composite panels are proposed in this study, namely Composite Structural Insulated Panels (CSIPs) for exterior walls, floors and roofs, and Open Core Sandwich composite for multifunctional interior walls of a structure. Special manufacturing techniques are developed for manufacturing these panels. The structural behavior of these panels is analyzed based on various building design codes. Detailed descriptions of the design, cost analysis, manufacturing, finite element modeling and structural testing of these proposed panels are included in this study in the of form five peer-reviewed journal articles. The structural testing of the proposed panels involved in this study included flexural testing, axial compression testing, and low and high velocity impact testing. Based on the current study, the proposed CSIP wall and floor panels were found satisfactory, based on building design codes ASCE-7-05 and ACI-318-05. Joining techniques are proposed in this study for connecting the precast panels on the construction

  14. Characterization of Polyimide Foams for Ultra-Lightweight Space Structures

    Science.gov (United States)

    Meador, Michael (Technical Monitor); Hillman, Keithan; Veazie, David R.

    2003-01-01

    Ultra-lightweight materials have played a significant role in nearly every area of human activity ranging from magnetic tapes and artificial organs to atmospheric balloons and space inflatables. The application range of ultra-lightweight materials in past decades has expanded dramatically due to their unsurpassed efficiency in terms of low weight and high compliance properties. A new generation of ultra-lightweight materials involving advanced polymeric materials, such as TEEK (TM) polyimide foams, is beginning to emerge to produce novel performance from ultra-lightweight systems for space applications. As a result, they require that special conditions be fulfilled to ensure adequate structural performance, shape retention, and thermal stability. It is therefore important and essential to develop methodologies for predicting the complex properties of ultra-lightweight foams. To support NASA programs such as the Reusable Launch Vehicle (RLV), Clark Atlanta University, along with SORDAL, Inc., has initiated projects for commercial process development of polyimide foams for the proposed cryogenic tank integrated structure (see figure 1). Fabrication and characterization of high temperature, advanced aerospace-grade polyimide foams and filled foam sandwich composites for specified lifetimes in NASA space applications, as well as quantifying the lifetime of components, are immensely attractive goals. In order to improve the development, durability, safety, and life cycle performance of ultra-lightweight polymeric foams, test methods for the properties are constant concerns in terms of timeliness, reliability, and cost. A major challenge is to identify the mechanisms of failures (i.e., core failure, interfacial debonding, and crack development) that are reflected in the measured properties. The long-term goal of the this research is to develop the tools and capabilities necessary to successfully engineer ultra-lightweight polymeric foams. The desire is to reduce density

  15. Plane symmetric cosmological models

    CERN Document Server

    Yadav, Anil Kumar; Ray, Saibal; Mallick, A

    2016-01-01

    In this work, we perform the Lie symmetry analysis on the Einstein-Maxwell field equations in plane symmetric spacetime. Here Lie point symmetries and optimal system of one dimensional subalgebras are determined. The similarity reductions and exact solutions are obtained in connection to the evolution of universe. The present study deals with the electromagnetic energy of inhomogeneous universe where $F_{12}$ is the non-vanishing component of electromagnetic field tensor. To get a deterministic solution, it is assumed that the free gravitational field is Petrov type-II non-degenerate. The electromagnetic field tensor $F_{12}$ is found to be positive and increasing function of time. As a special case, to validate the solution set, we discuss some physical and geometric properties of a specific sub-model.

  16. Duality and noncommutative planes

    DEFF Research Database (Denmark)

    Jøndrup, Søren

    2015-01-01

    We study extensions of simple modules over an associative ring A   and we prove that for twosided ideals mm and nn with artinian factors the condition ExtA1(A/m,A/n)≠0 holds for the left A  -modules A/mA/m and A/nA/n if and only if it holds for the right modules A/nA/n and A/mA/m. The methods pro...... proving this are applied to show that noncommutative models of the plane, i.e. algebras of the form k〈x,y〉/(f)k〈x,y〉/(f), where f∈([x,y])f∈([x,y]) are noetherian only in case (f)=([x,y])...

  17. Lightweight design of the rectangular mirror using topology optimization

    Science.gov (United States)

    Xiang, Meng; Li, Fu

    2014-09-01

    That minimizing the mass of space optical remote sensor at the same time guaranteeing of structural rigidity and surface shape accuracy, became a new critical research topic. This paper achieves detailed design of meniscus rectangular lens body structure by taking the choice of materials, design of supporting structure and lightweight form of mirror into account. And we established lightweight concrete of the mirror under self-weight by the method of topological optimization design. For the optimization, we used a 3-D model of the rectangular mirror and calculated based on that making minimum weight of the mirror as an objective function constrained by the displacement of the mirror surface. Finally finite element analysis method was adopted to get the optimization results analyzed and compared with the traditional triangular lightweight model. Analysis results prove that: the new mirror is superior to the traditional model in surface accuracy and structural rigidity, PV value, RMS value and the lightweight rate. With enough high dynamic-static stiffness and thermal stability, this kind of mirror can meet the demand under the self-weight and the random vibration environment respectively. So this article puts forward a new idea in the lightweight design of rectangular mirror.

  18. Optimum Design of Lightweight Silicon Carbide Mirror Assembly

    Institute of Scientific and Technical Information of China (English)

    HAN Yuanyuan; ZHANG Yumin; HAN Jiecai; ZHANG Jianhan; YAO Wang; ZHOU Yufeng

    2008-01-01

    According to the design requirement and on the basis of the principle that the thermal expansion coefficient of the support structure should match with that of the mirror, a lightweight silicon carbide primary mirror assembly was designed. Finite element analysis combined with the parameter-optimized method was used during the design. Lightweight cell and rigid rib structure were used for the mirror assembly. The static, dynamic and thermal properties of the primary mirror assembly were analyzed. It is shown that after optimization, the lightweight ratio of the silicon carbide mirror is 52.5%, and the rigidity of the silicon carbide structure is high enough to support the required mirror. When temperature changes, the deformation of the mirror surface is in proportion to the temperature difference.

  19. Second law evaluation of a lightweight cooling unit

    Directory of Open Access Journals (Sweden)

    Guilherme B. Ribeiro

    2016-03-01

    Full Text Available The analysis based on the second law of thermodynamics of a lightweight vapor compression refrigeration system is presented. A small-scale linear compressor was applied in a DC-powered portable cooler for vehicles and for the medical field, using finned-tube heat exchangers and R600-a (Isobutane as the working fluid. The cooler was tested in an environmental chamber (with controlled temperature and humidity under three different ambient temperatures (21, 25 and 32 °C in order to measure key parameters of the system, such as cooling capacity, power consumption and internal air temperature. For the comparison of thermodynamic irreversibilities, a conventional vapor compression refrigerating system was also tested under the same ambient conditions. Results indicated that the system with the proposed lightweight system kept the lowest internal air temperature with higher coefficients of performance, showing how a lightweight cooling unit can enlarge the use of refrigerating systems due to its attributes.

  20. Bond Strength Degradation of Corrosive Reinforced Lightweight Concrete

    Institute of Scientific and Technical Information of China (English)

    CHEN Yueshun; LU Yiyan; LI Houxiang; ZENG Sanhai

    2007-01-01

    The influence of reinforced bar corrosion on the bond degradation in lightweight concrete was studied. Accelerated constant current corrosion tests were performed on lightweight reinforced concrete samples, and the influential factors, such as protective layer thickness, reinforced bar diameter and corrosive level were investigated. The constant current step method was used to measure the electric resistance of the concrete protective cover, which was used to characterize the corrosion level of the rebar. Experimental results indicated that the corrosive resistance increased with increasing the cover dimension and decreasing the reinforced bar diameter, and the rate of decrease in the specimen impedance after cracking depended on the cover dimension. A new medium was offered for the further research on the performance degradation of corrosion lightweight concrete.

  1. Physique characteristics of Pan American Games lightweight rowers.

    Science.gov (United States)

    DeRose, E H; Crawford, S M; Kerr, D A; Ward, R; Ross, W D

    1989-08-01

    The emergence of lightweight rowing as an international sport has made the optimization of physique within the weight restrictions a matter of primary importance in selection and training of the participants. The occasion of the Xth Pan American Games provided opportunity to obtain comprehensive anthropometric data on 20 male and 13 female lightweight rower finalists including most of the medal winners. Anthropometric characteristics, somatotype, and proportionality profiles showed the male rowers to be similar in most aspects to a student control sample, with the exception of short sitting height and large transverse chest breadth. The females, on the other hand, appeared to be very different from the control sample, having a number of characteristics similar to those of Olympic rowers. The female lightweight rowers also uniquely demonstrated two distinct physique prototypes.

  2. Autogenous Shrinkage of High Strength Lightweight Aggregate Concrete

    Institute of Scientific and Technical Information of China (English)

    DING Qingjun; TIAN Yaogang; WANG Fazhou; ZHANG Feng; HU Shuguang

    2005-01-01

    The characteristic of autogenous shrinkage ( AS ) and its effect on high strength lightweight aggregate concrete (HSLAC) were studied. The experimental results show that the main shrinkage of high strength concrete is AS and the amount of cement can affect the AS of HSLAC remarkably. At the early stage the AS of HSLAC is lower than that of high strength normal concrete, but it has a large growth at the later stage. The AS of high strength normal concrete becomes stable at 90d age, but HSLAC still has a high AS growth. It is found that adjusting the volume rate of lightweight aggregate, mixing with a proper dosage of fly ash and raising the water saturation degree of lightweight aggregate can markedly reduce the AS rate of HSLAC.

  3. National Aerospace Plane Integrated Fuselage/Cryotank Risk Reduction program

    Science.gov (United States)

    Dayton, K. E.

    1993-06-01

    The principal objectives and results of the National Aerospace Plane (NASP) Integrated Risk Reduction program are briefly reviewed. The program demonstrated the feasibility of manufacturing lightweight advanced composite materials for single-stage-to-orbit hypersonic flight vehicle applications. A series of combined load simulation tests (thermal, mechanical, and cryogenic) demonstrated proof of concept performance for an all unlined composite cryogenic fuel tank with flat end bulkheads and a high-temperature thin-shell advanced composite fuselage. Temperatures of the fuselage were as high as 1300 F, with 100 percent bending and shear loads applied to the tank while filled with 850 gallons of cryogenic fluid hydrogen (-425 F). Leak rates measured on and around the cryotank shell and bulkheads were well below acceptable levels.

  4. The lightweight structure design of a CFRP mirror

    Science.gov (United States)

    Ding, Jiaoteng; Xu, Liang; Ma, Zhen; Xie, Yongjie; Luo, Yao; Wang, Yongjie; Pang, Zhihai

    2016-10-01

    The advantage of Carbon Fiber Reinforced Polymer (CFRP) is obvious as a common space material for low density, low thermal expansion coefficient and high specific stiffness characteristics, it is the ideal material choice for space optical reflector. Mirror structure with honeycomb can achieve high rates of lightweight, as well as high specific stiffness. For Φ300mm CFRP mirror, accounting of the actual process properties of CFRP, mirror panels laminated based on thermal stability design, honeycomb fabricated using one innovative inlaying-grafting design method. Finally, lightweight structure design of the CFRP primary mirror completed, the thermal stability result of the Φ300mm CFRP mirror achieved is 10nm°C.

  5. Overview of Lightweight Structures for Rotorcraft Engines and Drivetrains

    Science.gov (United States)

    Roberts, Gary D.

    2011-01-01

    This is an overview presentation of research being performed in the Advanced Materials Task within the NASA Subsonic Rotary Wing Project. This research is focused on technology areas that address both national goals and project goals for advanced rotorcraft. Specific technology areas discussed are: (1) high temperature materials for advanced turbines in turboshaft engines; (2) polymer matrix composites for lightweight drive system components; (3) lightweight structure approaches for noise and vibration control; and (4) an advanced metal alloy for lighter weight bearings and more reliable mechanical components. An overview of the technology in each area is discussed, and recent accomplishments are presented.

  6. Ground Fluidization Promotes Rapid Running of a Lightweight Robot

    Science.gov (United States)

    2013-01-01

    Ground fluidization promotes rapid running of a lightweight robot The International Journal of Robotics Research 32(7) 859–869 © The Author(s) 2013...continuously fluidized , and the robot “swam” forward slowly (∼ 0.01 body length/s) using drag on the legs to overcome belly drag. In contrast, a variety of...COVERED 00-00-2013 to 00-00-2013 4. TITLE AND SUBTITLE Ground fluidization promotes rapid running of a lightweight robot 5a. CONTRACT NUMBER 5b

  7. Development of light-weight spherical mirrors for RICH detectors

    CERN Document Server

    Metlica, Fabio

    2007-01-01

    Glass-coated beryllium and carbon-fiber light-weight spherical mirrors, with radii of curvature of $\\sim$ 2700mm, have been successfully developed and tested as part of the LHCb RICH experimental programme. The low mass mirror is necessary to minimize the amount of material within the LHCb spectrometer acceptance, with a requirement of less than 2% of a radiation length. Both technologies are suitable for light-weight mirror applications. The R&D and characterization of the mirrors are reported.

  8. Prediction of Noise Transmission in Lightweight Building Structures

    DEFF Research Database (Denmark)

    Dickow, Kristoffer Ahrens

    tool to predict the flanking transmission of air-borne and structure borne sound already at the design stage. However, lightweight building structures typically do not meet the requirements for ideal SEA subsystems and, therefore, applying the EN 12354 standard to lightweight building structures may...... papers are carried out as parametric studies in the commercial FE package ABAQUS. Finally, an experimental part, that focuses on the uncertainty and variation in wooden junctions, is included. Ten nominally identical plate/beam T-junctions are tested using experimental modal analysis, and the results...

  9. Evaluation and comparison of a lightweight bamboo composite

    Science.gov (United States)

    Loth, Andreas; Berwing, Michael; Förster, Ralf

    2016-10-01

    The demand for fast changing production lines and other facilities needs new lightweight and stable systems for partitioning walls. There is also a need for ecological products for this application. The wood like grass bamboo provides a wide potential to substitute conventional wood. A composite lightweight honeycomb like bamboo board was developed and compared with reinforced and unreinforced plywood specimen. The acquired mechanical properties gave a promising result for the usability of bamboo as basis material for wide span boards. It can be manufactured with minimal technical investments, that suits also well for regions with little industry. The ecological assessment of the structure is very positive.

  10. Reflective Coating for Lightweight X-Ray Optics

    Science.gov (United States)

    Chan, Kai-Wing; Zhang, William W.; Windt, David; Hong, Mao-Ling; Saha, Timo; McClelland, Ryan; Sharpe, Marton; Dwivedi, Vivek H.

    2012-01-01

    X-ray reflective coating for next generation's lightweight, high resolution, optics for astronomy requires thin-film deposition that is precisely fine-tuned so that it will not distort the thin sub-mm substrates. Film of very low stress is required. Alternatively, mirror distortion can be cancelled by precisely balancing the deformation from multiple films. We will present results on metallic film deposition for the lightweight optics under development. These efforts include: low-stress deposition by magnetron sputtering and atomic layer deposition of the metals, balancing of gross deformation with two-layer depositions of opposite stresses and with depositions on both sides of the thin mirrors.

  11. Plane Mercury librations

    Science.gov (United States)

    Barkin, Yu. V.; Ferrandiz, J. M.

    2009-04-01

    theory of Mercury librations in longitude by using three characteristics of Mercury rotation determined in the paper [3]. Two from these parameters are values of angle of librations in longitude and angular velocity in moment of passage of perihelion of Mercury orbit on 17 April 2002: (^g)0 = 0007 ± 0001, (^?•? )0 = (2.10± 0.06)•? ars/d. Third parameter determined in [3] is a dynamical coefficient: K = (B -A)•(4Cm ) = (5.08± 0.30) × 10-5. B > A are principal moment of inertia, corresponding to equatorial axes of inertia; Cm is a polar moment of inertia of the mantle of Mercury. 1 Analytical theory of plane Mercury librations. This theory describes forced and free librations of Mercury in longitude in the frame of plane problem about resonant librations of Mercury considered or as non-spherical rigid body, or as system of rigid non-spherical mantle and liquid ellipsoidal core. Saving the main terms for the perturbations of angle of librations ^g and angular velocity ^? in both mentioned cases we will have formulae [6]: ^g = K(E sin M + E sin2M + E sin 3M + E sin4M + E sin5M ) 1 2 3 4 5+K0 sin(E šKM- - φ) (A)

  12. Lightweight High Temperature Non-Eroding Throat Materials for Propulsion Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation in this proposed effort is the development of lightweight, non-eroding nozzle materials for use in propulsion systems. Lightweight structures are...

  13. Strength properties of cement slurries with lightweights applied in oil and gas wells

    Science.gov (United States)

    Bubnov, A. S.; Boyko, I. A.; Khorev, V. S.

    2015-02-01

    The article is focused on the cement stone strength properties resulted from lightweight cement slurries that meet GOST-1581-96 (state Standards) requirements. Exfoliated vermiculite, hollow aluminosilicate microspheres (HAMs), diatomite and perlite were used as lightweighting additives.

  14. Feasibility study of a 110 watt per kilogram lightweight solar array system

    Science.gov (United States)

    Shepard, N. F.; Stahle, C. V.; Schneider, A.; Hanson, K. L.

    1972-01-01

    An investigation of the feasibility of a solar array panel subsystem which will produce 10,000 watts of electrical output at 1 A.U. with an overall beginning-of-life power-to-weight ratio of at least 110 watt/kg is reported. A description of the current baseline configuration which meets these requirements is presented. A parametric analysis of the single boom, two blanket planar solar array system was performed to arrive at the optimum system aspect ratio. A novel concept for the stiffening of a lightweight solar array by canting the solar cell blankets at a small angle to take advantage of the inherent in-plane stiffness to increase the symmetric out-of-plane frequency is introduced along with a preliminary analysis of the stiffening effect. A comparison of welded and soldered solar cell interconnections leads to the conclusion that welding is required on this ultralightweight solar array. The use of a boron/aluminum composite material in a BI-STEM type deployable boom is investigated as a possible advancement in the state-of-the-art.

  15. Gravitational Couplings for Gop-Planes and y-Op-Planes

    CERN Document Server

    Ospina-Giraldo, J F

    2000-01-01

    The Wess-Zumino actions for generalized orientifold planes (GOp-planes) and y-deformed orientifold planes (yOp-planes) are presented and two series power expantions are realized from whiches processes that involves GOp-planes,yOp-planes, RR-forms, gravitons and gaugeons, are obtained. Finally non-standard GOp-planes and y-Op-planes are showed.

  16. Experimental study on the effect of volcanic residue on the performance of recycled lightweight aggregate concrete

    Science.gov (United States)

    Xiao, Li-guang; Li, Ji-heng; Liu, Qing-shun

    2017-08-01

    Recycled lightweight aggregate concrete prepared with waste brick recycled light aggregate has high water absorption, large apparent density and poor frost resistance. The technical measures of regen-erating lightweight aggregate concrete with modified waste bricks from volcanic slag are put forward. The effects of volcanic slag on the properties of waste lightweight aggregate concrete were studied. The experi-mental results show that volcanic slag can significantly reduce the apparent density of recycled lightweight aggregate concrete and improve its frost resistance.

  17. Evolutes of Hyperbolic Plane Curves

    Institute of Scientific and Technical Information of China (English)

    Shyuichi IZUMIYA; Dong He PEI; Takashi SANO; Erika TORII

    2004-01-01

    We define the notion of evolutes of curves in a hyperbolic plane and establish the relationships between singularities of these subjects and geometric invariants of curves under the action of the Lorentz group. We also describe how we can draw the picture of an evolute of a hyperbolic plane curve in the Poincar(e) disk.

  18. Conceptual Design of Wave Plane

    DEFF Research Database (Denmark)

    Frigaard, Peter; Trewers, Andrew; Kofoed, Jens Peter;

    The Wave Plane is a patented Wave Energy device of the overtopping type, designed to capture potential as well as kinetic energy. This is as such different to other overtopping devices, who usually only focus on potential energy. If Wave Plane A/S can deliver the turbine technology to utilize both...

  19. Evaluation of Flanking Noise Transmission within Periodically Distributed Lightweight Beam Elements

    DEFF Research Database (Denmark)

    Domadiya, Parthkumar Gandalal; Andersen, Lars Vabbersgaard; Sorokin, Sergey

    2012-01-01

    Wooden frame structures are highly preferred as lightweight building systems nowadays. Lightweight building structures have gained more interest due to lower cost of production. However, there is a growing concern regarding noise and vibration issues within lightweight structures. Sound may pass...

  20. Effect of Commercial Synthappret BAP Treatment on the Tailorabilitv of Light-Weight Worsted Wool Fabrics

    Institute of Scientific and Technical Information of China (English)

    Wang Gehui(王革辉); Zhang Weiyuan(张渭源); Postle, R.; Phillips, D.

    2001-01-01

    By means of measurement with the FAST instruments,the effect of commercial Synthappret BAP treatment on the tailorability of light-weight wool worsted fabrics has been investigated. It was found that the commercial Synthappret BAP treatment improved the tailorability of the light-weight wool fabrics mainly by increasing the bending stiffness of the light-weight wool fabrics.

  1. Density Optimization of Lithium Lanthanum Titanate Ceramics for Lightweight Lithium-Air Batteries

    Science.gov (United States)

    2014-11-01

    Density Optimization of Lithium Lanthanum Titanate Ceramics for Lightweight Lithium -Air Batteries by Claire Weiss Brennan, Victoria Blair...Ground, MD 21005-5069 ARL-TR-7145 November 2014 Density Optimization of Lithium Lanthanum Titanate Ceramics for Lightweight Lithium -Air...COVERED (From - To) 1 June–31 August 2014 4. TITLE AND SUBTITLE Density Optimization of Lithium Lanthanum Titanate Ceramics for Lightweight Lithium

  2. A purely flexible lightweight membrane-type acoustic metamaterial

    Science.gov (United States)

    Ma, Fuyin; Wu, Jiu Hui; Huang, Meng; Zhang, Weiquan; Zhang, Siwen

    2015-05-01

    This paper proposes a purely flexible lightweight membrane-type acoustic structure, wherein one kind of flexible lightweight rubber material takes the roles of mass and stiffness and another type of lightweight flexible EVA (ethylene-vinyl acetate copolymer) or plastic material functions as the localized stiffness for each unit. Because both the scatterers and base are constituted by the same material, this type of structure breaks the limitation that the metamaterials and phononic crystals need different materials with relatively large density and elasticity modulus ratios to play the roles of the scatterers and base respectively. Based on the band structures with different units, mass block shapes and size parameters, it is suggested that the shapes of the mass block can significantly affect the band structure. In addition, this type of structure could not only open a full band gap in the low-frequency range below 500 Hz, but also obtain an ultra-low-frequency bending wave band gap in the range below 100 Hz. Finally, we take into account the semi-infinite medium as a component, and calculate the sound transmission loss (STL) to evaluate the interaction between the structure and air. An experimental validation employing the cylindrical mass structure was developed to directly support the simulation results. Since the structures proposed in this study have achieved a purely flexible lightweight design, there exists an important promotion effect to realize the engineering applications of the acoustic metamaterials in practice.

  3. A Lightweight Intelligent Virtual Cinematography System for Machinima Production

    Science.gov (United States)

    2007-01-01

    A Lightweight Intelligent Virtual Cinematography System for Machinima Production David K. Elson1, Mark O. Riedl2 1Columbia University, Computer...However, creating quality cinematic visualizations with existing machinima techniques still requires a high degree of talent and effort. We...produces a cinematic visualization. Unlike other virtual cinematography systems, Cambot favors an offline algorithm coupled with an extensible

  4. Lightweight Inexpensive Ozone Lidar Telescope Using a Plastic Fresnel Lens

    Science.gov (United States)

    DeYoung, Russell J.; Notari, Anthony; Carrion, William; Pliutau, Denis

    2014-01-01

    An inexpensive lightweight ozone lidar telescope was designed, constructed and operated during an ozone lidar field campaign. This report summarizes the design parameters and performance of the plastic Fresnel lens telescope and shows the ozone lidar performance compared to Zemax calculations.

  5. FY2010 Annual Progress Report for Lightweighting Materials

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2011-01-15

    The Lightweight Materials activity (LM) within the Vehicle Technologies Program focuses on the development and validation of advanced materials and manufacturing technologies to significantly reduce light and heavy duty vehicle weight without compromising other attributes such as safety, performance, recyclability, and cost.

  6. STRENGTH OF NANOMODIFIED HIGH-STRENGTH LIGHTWEIGHT CONCRETES

    Directory of Open Access Journals (Sweden)

    NOZEMTСEV Alexandr Sergeevich

    2013-02-01

    Full Text Available The paper presents the results of research aimed at development of nanomodified high-strength lightweight concrete for construction. The developed concretes are of low average density and high ultimate compressive strength. It is shown that to produce this type of concrete one need to use hollow glass and aluminosilicate microspheres. To increase the durability of adhesion between cement stone and fine filler the authors offer to use complex nanodimensinal modifier based on iron hydroxide sol and silica sol as a surface nanomodifier for hollow microspheres. It is hypothesized that the proposed modifier has complex effect on the activity of the cement hydration and, at the same time increases bond strength between filler and cement-mineral matrix. The compositions for energy-efficient nanomodified high-strength lightweight concrete which density is 1300…1500 kg/m³ and compressive strength is 40…65 MPa have been developed. The approaches to the design of high-strength lightweight concrete with density of less than 2000 kg/m³ are formulated. It is noted that the proposed concretes possess dense homogeneous structure and moderate mobility. Thus, they allow processing by vibration during production. The economic and practical implications for realization of high-strength lightweight concrete in industrial production have been justified.

  7. Lightweighting Impacts on Fuel Economy, Cost, and Component Losses

    Energy Technology Data Exchange (ETDEWEB)

    Brooker, A. D.; Ward, J.; Wang, L.

    2013-01-01

    The Future Automotive Systems Technology Simulator (FASTSim) is the U.S. Department of Energy's high-level vehicle powertrain model developed at the National Renewable Energy Laboratory. It uses a time versus speed drive cycle to estimate the powertrain forces required to meet the cycle. It simulates the major vehicle powertrain components and their losses. It includes a cost model based on component sizing and fuel prices. FASTSim simulated different levels of lightweighting for four different powertrains: a conventional gasoline engine vehicle, a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), and a battery electric vehicle (EV). Weight reductions impacted the conventional vehicle's efficiency more than the HEV, PHEV and EV. Although lightweighting impacted the advanced vehicles' efficiency less, it reduced component cost and overall costs more. The PHEV and EV are less cost effective than the conventional vehicle and HEV using current battery costs. Assuming the DOE's battery cost target of $100/kWh, however, the PHEV attained similar cost and lightweighting benefits. Generally, lightweighting was cost effective when it costs less than $6/kg of mass eliminated.

  8. Design of Light-Weight High-Entropy Alloys

    Directory of Open Access Journals (Sweden)

    Rui Feng

    2016-09-01

    Full Text Available High-entropy alloys (HEAs are a new class of solid-solution alloys that have attracted worldwide attention for their outstanding properties. Owing to the demand from transportation and defense industries, light-weight HEAs have also garnered widespread interest from scientists for use as potential structural materials. Great efforts have been made to study the phase-formation rules of HEAs to accelerate and refine the discovery process. In this paper, many proposed solid-solution phase-formation rules are assessed, based on a series of known and newly-designed light-weight HEAs. The results indicate that these empirical rules work for most compositions but also fail for several alloys. Light-weight HEAs often involve the additions of Al and/or Ti in great amounts, resulting in large negative enthalpies for forming solid-solution phases and/or intermetallic compounds. Accordingly, these empirical rules need to be modified with the new experimental data. In contrast, CALPHAD (acronym of the calculation of phase diagrams method is demonstrated to be an effective approach to predict the phase formation in HEAs as a function of composition and temperature. Future perspectives on the design of light-weight HEAs are discussed in light of CALPHAD modeling and physical metallurgy principles.

  9. Annotating Evidence Based Clinical Guidelines: A Lightweight Ontology

    NARCIS (Netherlands)

    R. Hoekstra; A. de Waard; R. Vdovjak

    2012-01-01

    This paper describes a lightweight ontology for representing annotations of declarative evidence based clinical guidelines. We present the motivation and requirements for this representation, based on an analysis of several guidelines. The ontology provides the means to connect clinical questions an

  10. Closing the innovation cycle in lightweighting compressor pistons technolog

    NARCIS (Netherlands)

    Wentzel, C.; Eijk, A.; Groenewegen, G.; Bergsma, O.

    2016-01-01

    What started out as an exercise in exploring the weight reduction potential of those allegedly “heavy recip crossheads”, turned out to be a fast leap towards implementation of a new hybrid material concept for very lightweight pistons. This was enabled by a next phase in the EFRC R&D group research

  11. SPONGENT: The Design Space of Lightweight Cryptographic Hashing

    DEFF Research Database (Denmark)

    Bogdanov, Andrey; Knezevic, Miroslav; Leander, Gregor

    2013-01-01

    The design of secure yet efficiently implementable cryptographic algorithms is a fundamental problem of cryptography. Lately, lightweight cryptography--optimizing the algorithms to fit the most constrained environments--has received a great deal of attention, the recent research being mainly...

  12. Solar cell submodule design facilitates assembly of lightweight arrays

    Science.gov (United States)

    Yasui, R. K.

    1966-01-01

    Solar cell submodules with bus bars that leave tabs along one end of the submodule and wires with raised portions along the other end are assembled by interlocking the tabs and wires of adjacent submodules. This structural design is lightweight and reliable and requires no metallic substructure.

  13. APE: Authenticated Permutation-Based Encryption for Lightweight Cryptography

    NARCIS (Netherlands)

    Andreeva, Elena; Bilgin, Begül; Bogdanov, Andrey; Luykx, Atul; Mennink, Bart; Mouha, Nicky; Yasuda, Kan

    The domain of lightweight cryptography focuses on cryptographic algorithms for extremely constrained devices. It is very costly to avoid nonce reuse in such environments, because this requires either a hardware source of randomness, or non-volatile memory to store a counter. At the same time, a lot

  14. Application of CAE technology for Geely car lightweight

    Institute of Scientific and Technical Information of China (English)

    Men Yongxin; Ma Fangwu; Peng Hong; Li Yongsheng

    2012-01-01

    In order to reduce energy consumption and protect the human survival environment, the lightweight has became the development trend of the world automobile industry. On the premise of ensuring the strength, safety and driving performance of the car, the major car enterprises try to reduce the curb weight of the ear, fuel consumption and emissions. Not only a lot of new technologies and new products have been generated, but also joint vehicle development process and computer aided engineering (CAE) analysis technology have been developed. Since the entry into the "Au- tomobile Lightweight Technology Innovation Strategic Alliance" in Dec. 2007, Geely Group has been focusing on light- weight construction of vehicle and key assemblies in every stage of the vehicle product development. Among vehicles ap- peared on the market and in research, it has presented continuously better performance. The paper describes application examples and successful experience of CAE simulation analysis and performance optimization during the lightweight de- sign and development of a self-developed model of Geely, and looks forward to the prospects for the development of lightweight of Geely vehicle.

  15. Making mundane pleasures visible: mediating daily likings with lightweight technology

    NARCIS (Netherlands)

    Kanis, M.; Brinkman, W.-P.

    2010-01-01

    This article discusses the sharing of daily pleasures with lightweight technology. Two mobile applications called PosiPost Me (Mobile internet edition) and PosiPost Be (Bluetooth edition) were developed to understand the potential of remote and proximity-based sharing of positive messages. These imp

  16. A Light-Weight Statically Scheduled Network-on-Chip

    DEFF Research Database (Denmark)

    Sørensen, Rasmus Bo; Schoeberl, Martin; Sparsø, Jens

    2012-01-01

    This paper investigates how a light-weight, statically scheduled network-on-chip (NoC) for real-time systems can be designed and implemented. The NoC provides communication channels between all cores with equal bandwidth and latency. The design is FPGA-friendly and consumes a minimum of resources...

  17. FY2013 Lightweight Materials R&D Annual Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2014-02-01

    As part of the U.S. Department of Energy’s (DOE’s) Vehicle Technologies Program (VTO), the Lightweight Materials (LM) activity focuses on the development and validation of advanced materials and manufacturing technologies to significantly reduce light and heavy duty vehicle weight without compromising other attributes such as safety, performance, recyclability, and cost.

  18. Optical flows method for lightweight agile remote sensor design and instrumentation

    Science.gov (United States)

    Wang, Chong; Xing, Fei; Wang, Hongjian; You, Zheng

    2013-08-01

    Lightweight agile remote sensors have become one type of the most important payloads and were widely utilized in space reconnaissance and resource survey. These imaging sensors are designed to obtain the high spatial, temporary and spectral resolution imageries. Key techniques in instrumentation include flexible maneuvering, advanced imaging control algorithms and integrative measuring techniques, which are closely correlative or even acting as the bottle-necks for each other. Therefore, mutual restrictive problems must be solved and optimized. Optical flow is the critical model which to be fully represented in the information transferring as well as radiation energy flowing in dynamic imaging. For agile sensors, especially with wide-field-of view, imaging optical flows may distort and deviate seriously when they perform large angle attitude maneuvering imaging. The phenomena are mainly attributed to the geometrical characteristics of the three-dimensional earth surface as well as the coupled effects due to the complicated relative motion between the sensor and scene. Under this circumstance, velocity fields distribute nonlinearly, the imageries may badly be smeared or probably the geometrical structures are changed since the image velocity matching errors are not having been eliminated perfectly. In this paper, precise imaging optical flow model is established for agile remote sensors, for which optical flows evolving is factorized by two forms, which respectively due to translational movement and image shape changing. Moreover, base on that, agile remote sensors instrumentation was investigated. The main techniques which concern optical flow modeling include integrative design with lightweight star sensors along with micro inertial measurement units and corresponding data fusion, the assemblies of focal plane layout and control, imageries post processing for agile remote sensors etc. Some experiments show that the optical analyzing method is effective to

  19. Multiaxis, Lightweight, Computer-Controlled Exercise System

    Science.gov (United States)

    Haynes, Leonard; Bachrach, Benjamin; Harvey, William

    2006-01-01

    The multipurpose, multiaxial, isokinetic dynamometer (MMID) is a computer-controlled system of exercise machinery that can serve as a means for quantitatively assessing a subject s muscle coordination, range of motion, strength, and overall physical condition with respect to a wide variety of forces, motions, and exercise regimens. The MMID is easily reconfigurable and compactly stowable and, in comparison with prior computer-controlled exercise systems, it weighs less, costs less, and offers more capabilities. Whereas a typical prior isokinetic exercise machine is limited to operation in only one plane, the MMID can operate along any path. In addition, the MMID is not limited to the isokinetic (constant-speed) mode of operation. The MMID provides for control and/or measurement of position, force, and/or speed of exertion in as many as six degrees of freedom simultaneously; hence, it can accommodate more complex, more nearly natural combinations of motions and, in so doing, offers greater capabilities for physical conditioning and evaluation. The MMID (see figure) includes as many as eight active modules, each of which can be anchored to a floor, wall, ceiling, or other fixed object. A cable is payed out from a reel in each module to a bar or other suitable object that is gripped and manipulated by the subject. The reel is driven by a DC brushless motor or other suitable electric motor via a gear reduction unit. The motor can be made to function as either a driver or an electromagnetic brake, depending on the required nature of the interaction with the subject. The module includes a force and a displacement sensor for real-time monitoring of the tension in and displacement of the cable, respectively. In response to commands from a control computer, the motor can be operated to generate a required tension in the cable, to displace the cable a required distance, or to reel the cable in or out at a required speed. The computer can be programmed, either locally or via

  20. Next-Generation MKIII Lightweight HUT/Hatch Assembly

    Science.gov (United States)

    McCarthy, Mike; Toscano, Ralph

    2013-01-01

    The MK III (H-1) carbon-graphite/ epoxy Hard Upper Torso (HUT)/Hatch assembly was designed, fabricated, and tested in the early 1990s. The spacesuit represented an 8.3 psi (˜58 kPa) technology demonstrator model of a zero prebreathe suit. The basic torso shell, brief, and hip areas of the suit were composed of a carbon-graphite/epoxy composite lay-up. In its current configuration, the suit weighs approximately 120 lb (˜54 kg). However, since future planetary suits will be designed to operate at 0.26 bar (˜26 kPa), it was felt that the suit's re-designed weight could be reduced to 79 lb (˜35 kg) with the incorporation of lightweight structural materials. Many robust, lightweight structures based on the technologies of advanced honeycomb materials, revolutionary new composite laminates, metal matrix composites, and recent breakthroughs in fullerene fillers and nanotechnology lend themselves well to applications requiring materials that are both light and strong. The major problem involves the reduction in weight of the HUT/ Hatch assembly for use in lunar and/or planetary applications, while at the same time maintaining a robust structural design. The technical objective is to research, design, and develop manufacturing methods that support fa b rica - tion of a lightweight HUT/Hatch assembly using advanced material and geometric redesign as necessary. Additionally, the lightweight HUT/Hatch assembly will interface directly with current MK III hardware. Using the new operating pressure and current MK III (H-1) interfaces as a starting block, it is planned to maximize HUT/Hatch assembly weight reduction through material selection and geometric redesign. A hard upper torso shell structure with rear-entry closure and corresponding hatch will be fabricated. The lightweight HUT/Hatch assembly will retrofit and interface with existing MK III (H-1) hardware elements, providing NASA with immediate "plug-andplay" capability. NASA crewmembers will have a lightweight

  1. Lightweight autoclavable wide-angle contact lens for vitreous surgery.

    Science.gov (United States)

    Chalam, K V; Gupta, Shailesh K; Agarwal, Swati

    2007-01-01

    The authors describe an autoclavable, self-stabilizing, lightweight wide-angle contact lens for vitrectomy. The lens has two optical pieces with perforated plastic casing to sustain a high temperature (150 degrees C) for autoclaving. The lens has a 106 degrees static and 127 degrees dynamic field of view. The footplates and reduced weight (2.4 grams) due to the plastic casing allow self-stabilization of the lens. The open lens design.with high temperature resistant plastic prevents fogging during autoclaving and surgery. The autoclavable, self-stabilizing, lightweight wide-angle contact lens allows visualization of the peripheral retina during surgery and faster sterilization by autoclaving between surgeries without the disadvantage of lens fogging.

  2. Hot stamping advanced manufacturing technology of lightweight car body

    CERN Document Server

    Hu, Ping; He, Bin

    2017-01-01

    This book summarizes the advanced manufacturing technology of original innovations in hot stamping of lightweight car body. A detailed description of the technical system and basic knowledge of sheet metal forming is given, which helps readers quickly understand the relevant knowledge in the field. Emphasis has been placed on the independently developed hot stamping process and equipment, which help describe the theoretical and experimental research on key problems involving stress field, thermal field and phase transformation field in hot stamping process. Also, a description of the formability at elevated temperature and the numerical simulation algorithms for high strength steel hot stamping is given in combination with the experiments. Finally, the book presents some application cases of hot stamping technology such as the lightweight car body design using hot stamping components and gradient hardness components, and the cooling design of the stamping tool. This book is intended for researchers, engineers...

  3. Tendon-Actuated Lightweight In-Space MANipulator (TALISMAN)

    Science.gov (United States)

    Dorsey, John T.; Doggett, William R.; Komendera, Erik E.

    2015-01-01

    The robotic architecture of State-of-the-Art (SOA) space manipulators, represented by the Shuttle Remote Manipulator System (SRMS), inherently limits their capabilities to extend reach, reduce mass, apply force and package efficiently. TALISMAN uses a new and innovative robotic architecture that incorporates a combination of lightweight truss links, a novel hinge joint, tendon-articulation and passive tension stiffening to achieve revolutionary performance. A TALISMAN with performance similar to the SRMS has 1/10th of its mass and packages in 1/7th of its volume. The TALISMAN architecture allows its reach to be scaled over a large range; from 10 to over 300 meters. In addition, the dexterity (number of degrees-of-freedom) can be easily adjusted without significantly impacting manipulator mass because the joints are very lightweight.

  4. Computational imaging using lightweight diffractive-refractive optics

    KAUST Repository

    Peng, Yifan

    2015-11-23

    Diffractive optical elements (DOE) show great promise for imaging optics that are thinner and more lightweight than conventional refractive lenses while preserving their light efficiency. Unfortunately, severe spectral dispersion currently limits the use of DOEs in consumer-level lens design. In this article, we jointly design lightweight diffractive-refractive optics and post-processing algorithms to enable imaging under white light illumination. Using the Fresnel lens as a general platform, we show three phase-plate designs, including a super-thin stacked plate design, a diffractive-refractive-hybrid lens, and a phase coded-aperture lens. Combined with cross-channel deconvolution algorithm, both spherical and chromatic aberrations are corrected. Experimental results indicate that using our computational imaging approach, diffractive-refractive optics is an alternative candidate to build light efficient and thin optics for white light imaging.

  5. Computational imaging using lightweight diffractive-refractive optics.

    Science.gov (United States)

    Peng, Yifan; Fu, Qiang; Amata, Hadi; Su, Shuochen; Heide, Felix; Heidrich, Wolfgang

    2015-11-30

    Diffractive optical elements (DOE) show great promise for imaging optics that are thinner and more lightweight than conventional refractive lenses while preserving their light efficiency. Unfortunately, severe spectral dispersion currently limits the use of DOEs in consumer-level lens design. In this article, we jointly design lightweight diffractive-refractive optics and post-processing algorithms to enable imaging under white light illumination. Using the Fresnel lens as a general platform, we show three phase-plate designs, including a super-thin stacked plate design, a diffractive-refractive-hybrid lens, and a phase coded-aperture lens. Combined with cross-channel deconvolution algorithm, both spherical and chromatic aberrations are corrected. Experimental results indicate that using our computational imaging approach, diffractive-refractive optics is an alternative candidate to build light efficient and thin optics for white light imaging.

  6. Experimental Validation of a Dynamic Model for Lightweight Robots

    Directory of Open Access Journals (Sweden)

    Alessandro Gasparetto

    2013-03-01

    Full Text Available Nowadays, one of the main topics in robotics research is dynamic performance improvement by means of a lightening of the overall system structure. The effective motion and control of these lightweight robotic systems occurs with the use of suitable motion planning and control process. In order to do so, model-based approaches can be adopted by exploiting accurate dynamic models that take into account the inertial and elastic terms that are usually neglected in a heavy rigid link configuration. In this paper, an effective method for modelling spatial lightweight industrial robots based on an Equivalent Rigid Link System approach is considered from an experimental validation perspective. A dynamic simulator implementing the formulation is used and an experimental test-bench is set-up. Experimental tests are carried out with a benchmark L-shape mechanism.

  7. BEHAVIOUR OF LIGHTWEIGHT CONCRETE CONTAINING PERIWINKLE SHELLS AT ELEVATED TEMPERATURE

    Directory of Open Access Journals (Sweden)

    F. FALADE

    2010-12-01

    Full Text Available This study presents the results of the investigation of the response of lightweight concrete to elevated temperature. Available literature indicates that research works have not been carried out in this area. The variables are: mix proportion, water/cement ratio, curing age and temperature. The parameters that were measured are: compressive strength, density and bond characteristics of the concrete matrix. The results showed that the compressive strength of concrete decreased with increase in water/cement ratio and temperature but increased with increase in curing age and cement content while the density decreased with increase in temperature. The bond between the concrete matrix also decreased as the temperature increased. Lightweight concrete containing periwinkle shells is only suitable for structures that will be subjected to temperature less than 300oC.

  8. MODULTEC - Modular technology for lightweight vehicles; MODULTEC - Modultechnologie fuer Leichtmobile

    Energy Technology Data Exchange (ETDEWEB)

    Horlacher, M.; Efler, T.; Wegmann, S.

    2003-07-01

    This final report for the Swiss Federal Office of Energy presents the results of two research projects (MODULTEC I and II) that were carried out between 1995 and 2002. The project's aims were to develop and assess components for light-weight car bodies, study and test novel reinforced plastic materials and to examine the industrial implementation of light-weight vehicles. The report presents details on prototype vehicles and transport systems, as well as crash tests. The development of compound plastics and appropriate adhesives is discussed as is the co-operation with various industrial partners. Various prototype components are described and other associated topics such as recycling, storage of alternative fuels and pedestrian protection issues are discussed.

  9. Cost-effective lightweight mirrors for aerospace and defense

    Science.gov (United States)

    Woodard, Kenneth S.; Comstock, Lovell E.; Wamboldt, Leonard; Roy, Brian P.

    2015-05-01

    The demand for high performance, lightweight mirrors was historically driven by aerospace and defense (A&D) but now we are also seeing similar requirements for commercial applications. These applications range from aerospace-like platforms such as small unmanned aircraft for agricultural, mineral and pollutant aerial mapping to an eye tracking gimbaled mirror for optometry offices. While aerospace and defense businesses can often justify the high cost of exotic, low density materials, commercial products rarely can. Also, to obtain high performance with low overall optical system weight, aspheric surfaces are often prescribed. This may drive the manufacturing process to diamond machining thus requiring the reflective side of the mirror to be a diamond machinable material. This paper summarizes the diamond machined finishing and coating of some high performance, lightweight designs using non-exotic substrates to achieve cost effective mirrors. The results indicate that these processes can meet typical aerospace and defense requirements but may also be competitive in some commercial applications.

  10. Tailored Buckling Microlattices as Reusable Light-Weight Shock Absorbers.

    Science.gov (United States)

    Frenzel, Tobias; Findeisen, Claudio; Kadic, Muamer; Gumbsch, Peter; Wegener, Martin

    2016-07-01

    Structures and materials absorbing mechanical (shock) energy commonly exploit either viscoelasticity or destructive modifications. Based on a class of uniaxial light-weight geometrically nonlinear mechanical microlattices and using buckling of inner elements, either a sequence of snap-ins followed by irreversible hysteretic - yet repeatable - self-recovery or multistability is achieved, enabling programmable behavior. Proof-of-principle experiments on three-dimensional polymer microstructures are presented.

  11. Lightweight Sandwich Panel in Cold Stores and Refrigerated Warehouses

    OpenAIRE

    Chidom, Charles

    2013-01-01

    The use of sandwich panels has gained considerable recognition in the construction industry and more use of this composite structure is ever increasing. This study highlights and familiarizes the use of lightweight sandwich panel in refrigerated warehouses and cold storage facility and construction and the challenges such construction faces in warm climates considering the effects of thermal load. The study was commissioned by HAMK Sheet Metal Center, the steel research and development ce...

  12. Ultra-lightweight mirror manufacturing and radiation response study

    Science.gov (United States)

    Fitzsimmons, T. C.; Crowe, D. A.

    1981-08-01

    The requirements for making ultra-lightweight mirrors of Ultra-Low Expansion (ULE) fused silica by frit bonding are investigated. A manufacturing assessment of the facilities needed to scale the mirror technology to 4 meters in diameter is included. A front surface flux loading thermal test of a.5M diameter frit bonded ULE mirror is also included. The test was supported by detailed modeling and analysis.

  13. Lightweight shape memory self-deployable structures for Gossamer applications

    Science.gov (United States)

    Sokolowski, Witold

    2004-01-01

    Currently, existing approaches for producing large, ultra-lightweight, deployable structures in space typically rely upon electro-mechanical mechanisms and mechanically expandable that are heavy, not stowage volume efficient, expensive and complex. Therefore, one of the major efforts at NASA and DoD has been to develop expandable structures characterized by low mass and small launch volume. As a result, space inflatable structures have emerged 9-10 years ago.

  14. Magnesium Technology and Manufacturing for Ultra Lightweight Armored Ground Vehicles

    Science.gov (United States)

    2009-02-01

    Bruce Davis and Rick DeLorme Magnesium Elektron North America, Inc. A reprint from the Proceedings of the 2008 Army Science Conference...SUPPLEMENTARY NOTES *Magnesium Elektron North America, Inc., 1001 College St., Madison, IL 62060 A reprint from the Proceedings of the 2008 Army Science...initial emphasis on the Elektron WE43 alloy system for lightweight armored ground vehicle applications. Engineering design factors are reviewed and

  15. Polymer Substrates For Lightweight, Thin-Film Solar Cells

    Science.gov (United States)

    Lewis, Carol R.

    1993-01-01

    Substrates survive high deposition temperatures. High-temperature-resistant polymers candidate materials for use as substrates of lightweight, flexible, radiation-resistant solar photovoltaic cells. According to proposal, thin films of copper indium diselenide or cadmium telluride deposited on substrates to serve as active semiconductor layers of cells, parts of photovoltaic power arrays having exceptionally high power-to-weight ratios. Flexibility of cells exploited to make arrays rolled up for storage.

  16. Light-weight cyptography for resource constrained environments

    Science.gov (United States)

    Baier, Patrick; Szu, Harold

    2006-04-01

    We give a survey of "light-weight" encryption algorithms designed to maximise security within tight resource constraints (limited memory, power consumption, processor speed, chip area, etc.) The target applications of such algorithms are RFIDs, smart cards, mobile phones, etc., which may store, process and transmit sensitive data, but at the same time do not always support conventional strong algorithms. A survey of existing algorithms is given and new proposal is introduced.

  17. Mechanical, Thermal and Functional Properties of Green Lightweight Foamcrete

    OpenAIRE

    Md Azree Othuman Mydin; Norizal Md Noordin

    2012-01-01

    In recent times, the construction industry has revealed noteworthy attention in the use of lightweight foamcrete as a building material due to its many favourable characteristics such as lighter weight, easy to fabricate, durable and cost effective. Foamcrete is a material consisting of Portland cement paste or cement filler matrix (mortar) with a homogeneous pore structure created by introducing air in the form of small bubbles. With a proper control in dosage of foam and m...

  18. Deployment of Lightweight Shock Mitigating Boat Manufacturing Innovation

    Science.gov (United States)

    2012-12-21

    VARTM Hull 1267 760 Deck 702 399 Console 540 350 Total 2509 1509 % Current 100% 60% % Savings - 40% Deployment of Lightweight Shock Mitigating...1430 47 Weight Evaluation- Baseline Boat Weights (lb) Segment Baseline 850 A 850 B 850 B-OM Fabrication Method Open Mold Open Mold VARTM Open...Segment Baseline 850 A 850 B 850 B-OM Fabrication Method Open Mold Open Mold VARTM Open Mold Hull 1115 843 717 789 Deck 665 587 481 529

  19. Characterization of porous acoustic materials applied to lightweight partition walls

    OpenAIRE

    Fangueiro, Raúl; Velosa, J. C.; Macieira, Mónica; Mendonça, Paulo

    2011-01-01

    The increased need to save material and energetic resources, allied with a growing concern on the environmental issues and incertitude on the evolution of the economy, has impelled minimalist-approaches to Architecture and Engineering, reducing to the minimum necessary expression the building elements. The development of new lightweight materials, most of them composites with fibrous reinforcement systems, has interest for building materials and textile industries. However, the...

  20. Analysis of Lightweight Materials for the AM2 System

    Science.gov (United States)

    2014-06-01

    crack propagation. Like most non- ferrous alloys , 6061-T6 alloy does not exhibit an endurance limit and failure can occur up to at least 109 cycles...materials that could replace the 6061-T6 aluminum alloy currently used in the AM2 airfield matting for the purpose of light-weighting the design. An in...operating conditions of the AM2. Newly developed extruded magnesium alloys were identified that could potentially provide weight savings of 30 to 40

  1. Mechanical analysis of lightweight constructions manufactured with fused deposition modeling

    Science.gov (United States)

    Bagsik, A.; Josupeit, S.; Schoeppner, V.; Klemp, E.

    2014-05-01

    Additive production techniques have the advantage of manufacturing parts without needing a forming tool. One of the most used additive manufacturing processes is "Fused Deposition Modeling" (FDM) which allows the production of prototypes and end-use parts. Due to the manufacture layer by layer, also complex part geometries can be created in one working step. Furthermore, lightweight parts with specific inner core structures can be manufactured in order to achieve good weightrelated strength properties. In this paper the mechanical behavior of lightweight parts manufactured with the 3D production system Fortus 400mc from Stratasys and the material Polyetherimide (PEI) with the trade name Ultem*9085 is analyzed. The test specimens were built up with different inner structures and building directions. Therefore, test specimens with known lightweight core geometries (e.g. corrugated and honeycomb cores) were designed. A four-point bending test was conducted to analyze the strength properties as well as the weight-related strength properties. Additionally the influence of the structure width, the structure wall thickness and the top layer thickness was analyzed using a honeycomb structure.

  2. Moisture and Thermal Conductivity of Lightweight Block Walls

    Science.gov (United States)

    Joosep, R.

    2015-11-01

    This article examines thermal properties of lightweight block walls and their changes over the course of time. Three different types of lightweight blocks and two types of heat insulation are used in construction. Aeroc aerated concrete blocks are in use, as well as compacted LECA (Lightweight Expanded Clay Aggregate) Fibo blocks made from burned clay and Silbet blocks produced from oil shale ash. Expanded Thermisol EPS60F polystyrene plates and glass wool Isover OL-P plates are used for thermal insulation. The actual and computational values of thermal conductivity and the water draining properties of walls over time are compared in this article. Water draining from glass wool walls is relatively fast. Water-draining can take over a year in polystyrene insulated walls. All four wall constructions can be used as external walls, but care must be taken regarding the moisture content of the blocks during construction (the construction should be handled with care to minimise the moisture in the blocks), especially in polystyrene board-insulated walls.

  3. Vehicular hydrogen storage using lightweight tanks (regenerative fuel cell systems)

    Energy Technology Data Exchange (ETDEWEB)

    Mitlitsky, F; Myers, B; Weisberg, A H

    1999-06-01

    Energy storage systems with extremely high specific energy (>400 Wh/kg) have been designed that use lightweight tankage to contain the gases generated by reversible (unitized) regenerative fuel cells (URFCs). Lawrence Livermore National Laboratory (LLNL) will leverage work for aerospace applications supported by other sponsors (including BMDO, NASA, and USAF) to develop URFC systems for transportation and utility applications. Lightweight tankage is important for primary fuel cell powered vehicles that use on-board storage of hydrogen. Lightweight pressure vessels with state-of-the-art performance factors were designed, and prototypes are being fabricated to meet the DOE 2000 goals (4000 Wh/kg, 12% hydrogen by weight, 700 Wh/liter, and $20/kWh in high volume production). These pressure vessels use technologies that are easily adopted by industrial partners. Advanced liners provide permeation barriers for gas storage and are mandrels for composite overwrap. URFCs are important to the efficient use of hydrogen as a transportation fuel and enabler of renewable energy. H{sub 2}/halogen URFCs may be advantageous for stationary applications whereas H{sub 2}/O{sub 2} or H{sub 2}/air URFCs are advantageous for vehicular applications. URFC research and development is required to improve performance (efficiency), reduce catalyst loading, understand engineering operation, and integrate systems. LLNL has the experimental equipment and advanced URFC membrane electrode assemblies (some with reduced catalyst loading) for evaluating commercial hardware (not funded by DOE in FY1999).

  4. Ceramic/polymer functionally graded material (FGM) lightweight armor system

    Energy Technology Data Exchange (ETDEWEB)

    Petrovic, J.J.; McClellan, K.J.

    1998-12-31

    This is the final report of a two-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Functionally graded material is an enabling technology for lightweight body armor improvements. The objective was to demonstrate the ability to produce functionally graded ceramic-polymer and ceramic-metal lightweight armor materials. This objective involved two aspects. The first and key aspect was the development of graded-porosity boron-carbide ceramic microstructures. The second aspect was the development of techniques for liquid infiltration of lightweight metals and polymers into the graded-porosity ceramic. The authors were successful in synthesizing boron-carbide ceramic microstructures with graded porosity. These graded-porosity boron-carbide hot-pressed pieces were then successfully liquid-infiltrated in vacuum with molten aluminum at 1,300 C, and with liquid polymers at room temperature. Thus, they were able to demonstrate the feasibility of producing boron carbide-aluminum and boron carbide-polymer functionally graded materials.

  5. Lightweight ZERODUR: Validation of Mirror Performance and Mirror Modeling Predictions

    Science.gov (United States)

    Hull, Tony; Stahl, H. Philip; Westerhoff, Thomas; Valente, Martin; Brooks, Thomas; Eng, Ron

    2017-01-01

    Upcoming spaceborne missions, both moderate and large in scale, require extreme dimensional stability while relying both upon established lightweight mirror materials, and also upon accurate modeling methods to predict performance under varying boundary conditions. We describe tests, recently performed at NASA's XRCF chambers and laboratories in Huntsville Alabama, during which a 1.2 m diameter, f/1.2988% lightweighted SCHOTT lightweighted ZERODUR(TradeMark) mirror was tested for thermal stability under static loads in steps down to 230K. Test results are compared to model predictions, based upon recently published data on ZERODUR(TradeMark). In addition to monitoring the mirror surface for thermal perturbations in XRCF Thermal Vacuum tests, static load gravity deformations have been measured and compared to model predictions. Also the Modal Response(dynamic disturbance) was measured and compared to model. We will discuss the fabrication approach and optomechanical design of the ZERODUR(TradeMark) mirror substrate by SCHOTT, its optical preparation for test by Arizona Optical Systems (AOS). Summarize the outcome of NASA's XRCF tests and model validations

  6. Ceramic/polymer functionally graded material (FGM) lightweight armor system

    Energy Technology Data Exchange (ETDEWEB)

    Petrovic, J.J.; McClellan, K.J.

    1998-12-31

    This is the final report of a two-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Functionally graded material is an enabling technology for lightweight body armor improvements. The objective was to demonstrate the ability to produce functionally graded ceramic-polymer and ceramic-metal lightweight armor materials. This objective involved two aspects. The first and key aspect was the development of graded-porosity boron-carbide ceramic microstructures. The second aspect was the development of techniques for liquid infiltration of lightweight metals and polymers into the graded-porosity ceramic. The authors were successful in synthesizing boron-carbide ceramic microstructures with graded porosity. These graded-porosity boron-carbide hot-pressed pieces were then successfully liquid-infiltrated in vacuum with molten aluminum at 1,300 C, and with liquid polymers at room temperature. Thus, they were able to demonstrate the feasibility of producing boron carbide-aluminum and boron carbide-polymer functionally graded materials.

  7. Hummingbird: Ultra-Lightweight Cryptography for Resource-Constrained Devices

    Science.gov (United States)

    Engels, Daniel; Fan, Xinxin; Gong, Guang; Hu, Honggang; Smith, Eric M.

    Due to the tight cost and constrained resources of high-volume consumer devices such as RFID tags, smart cards and wireless sensor nodes, it is desirable to employ lightweight and specialized cryptographic primitives for many security applications. Motivated by the design of the well-known Enigma machine, we present a novel ultra-lightweight cryptographic algorithm, referred to as Hummingbird, for resource-constrained devices in this paper. Hummingbird can provide the designed security with small block size and is resistant to the most common attacks such as linear and differential cryptanalysis. Furthermore, we also present efficient software implementation of Hummingbird on the 8-bit microcontroller ATmega128L from Atmel and the 16-bit microcontroller MSP430 from Texas Instruments, respectively. Our experimental results show that after a system initialization phase Hummingbird can achieve up to 147 and 4.7 times faster throughput for a size-optimized and a speed-optimized implementations, respectively, when compared to the state-of-the-art ultra-lightweight block cipher PRESENT[10] on the similar platforms.

  8. Mechanical Properties of Fiber Reinforced Lightweight Concrete Containing Surfactant

    Directory of Open Access Journals (Sweden)

    Yoo-Jae Kim

    2010-01-01

    Full Text Available Fiber reinforced aerated lightweight concrete (FALC was developed to reduce concrete's density and to improve its fire resistance, thermal conductivity, and energy absorption. Compression tests were performed to determine basic properties of FALC. The primary independent variables were the types and volume fraction of fibers, and the amount of air in the concrete. Polypropylene and carbon fibers were investigated at 0, 1, 2, 3, and 4% volume ratios. The lightweight aggregate used was made of expanded clay. A self-compaction agent was used to reduce the water-cement ratio and keep good workability. A surfactant was also added to introduce air into the concrete. This study provides basic information regarding the mechanical properties of FALC and compares FALC with fiber reinforced lightweight concrete. The properties investigated include the unit weight, uniaxial compressive strength, modulus of elasticity, and toughness index. Based on the properties, a stress-strain prediction model was proposed. It was demonstrated that the proposed model accurately predicts the stress-strain behavior of FALC.

  9. Sediment and plankton lift off recirculations in strong synthetic turbulence (KS)

    Science.gov (United States)

    Redondo, Jose M.; Castilla, Roberto; Sekula, Emil; Furmanek, Petr

    2014-05-01

    The study of particle diffusion and of turbulent sedimentation is of great importance in many geophysical fields, such as in Environmental Science or Oceanography as well as in Bio-environmental and industrial processes. For a long time, the study of diffusion was numerically computed with random free paths, which gives Brownian behavior. (Richardson 1929). These stochastics methods have the objection that do not take into account the flow profile. On the other hand, there are many ways to simulate a fluid flow, but when this is turbulent our aim is to simulate the behaviour of neutral or heavy and inertial particles of biological or geological nature in a turbulent flow, in a simple way with a kinematically simulated model and to validate the results. We use the Kinematic Simulation (KS) model, also known as Synthetic Turbulence, suggested by Kraichnan (1966) and developed further by Castilla et al.(2007), Nicolleau et al.(2012). In this model, velocity field is generated through a Fourier series of random modes. The typical scales and the energy spectrum of the turbulence are inputs of the model. As we do not solve the flow in a discrete grid, but use a random predictive expression, we can simulate the flow at the smallest scales. In an unstratified flow, a KS flow field consists of a random, truncated Fourier representation in space and time, subject to constraints associated with incompressibility, and a prescribed initial energy spectrum. For stratified calculations, two further constraints are imposed, associated with the internal wave field in stratified flows, and the tendency of density variations to suppress vertical motion. With these model modifications, good agreement is found between KS and DNS with regard to the confinement in the vertical direction characteristic of stratified turbulence. Since stratifed flows exhibit this vertical confinement, KS in strictly two dimensions was considered as a first step to understanding dispersion within a stratified flow. The properties of ensemble averages of the separation between two particles in a 2D turbulent flow were considered, and the KS approach was found to give satisfactory answers, with good comparison to experiment. We also compare structure and intermittency between KS and DNS. And experiments (Redondo 1988) The dynamical processes associated with the stably stratified atmospheric boundary layer or in the ocean thermocline are less well understood than those of its convective counterparts. This is due to its complexity, and the fact that buoyancy reduces entrainment across density interfaces. We present results on a numerical simulation of homogeneous and density stratified fluids and of comparable laboratory experiments where a sharp density interface generated by either salt concentration or heat, advances due to grid stirred turbulence Redondo (1988, 1990). The appearance of bursts of turbulence in very stable conditions due to breaking up of the internal waves, confers a sporadic character to the turbulence; these conditions of non-fully developed turbulence could explain this unusual behaviour of the scaling exponents. (Mahjoub et al. 1998, 20009 The structure functions show, in the inertial range, a potential law . The relation is concave in strong mixing situations (instability with fully developed turbulence), and convex in very stable situations (in which the breaking up of the interval waves confers a sporadic character to the turbulence).The multifractal model can not be used to represent situations of non-fully developed turbulence but the use of structure function analysis allows the investigation of intermittent and scale to scale energy transfer even in local non equilibrium flows. The relative diffusion of tracers is strongly dependent on the slope of the energy spectra which tends to Richardson's law also for very steep spectra. (Castilla et al. 2007) Local turbulence is used to establish the geometry of the turbulence mixing, changes in the equilibrium (or not) cascade may lead to more physically realistic (and understandable) models to

  10. Griffin Lifts Off at NASA With Calls for Speeding Shuttle Replacement, Reopening Hubble Decision

    Science.gov (United States)

    Morring, Frank, Jr.

    2005-01-01

    Michael D. Griffin launched his tenure as NASA's 11th administrator on a fast track, using his "emergency" confiimation by the U.S. Senate to plug himself into space shuttle return-to-flight decision-making and urging faster development of the shuttle replacement. He also deftly sidestepped the treacherous issue of letting the aging Hubble Space Telescope die that was left behind by former Administrator Sean O'Keefe. Griffin told the Senate Commerce, Science and Transportation Committee that he would take another look at a shuttle mission to service the telescope, but not until the redesigned shuttle system makes a couple of test flights. Griffin made clear at his confirmation hearing Apr. 12 that he has long supported the ideas embodied in President Bush s push to move human exploration out of low Earth orbit, while finishing the International Space Station and retiring the space shuttle as soon as possible. And he showed right out of the blocks that his technical training and management background should serve him well in implementing Bush's directives.

  11. Lifting off the Ground to Return Anew: Mediated Praxis, Transformative Learning, and Social Design Experiments

    Science.gov (United States)

    Gutierrez, Kris D.; Vossoughi, Shirin

    2010-01-01

    This article examines a praxis model of teacher education and advances a new method for engaging novice teachers in reflective practice and robust teacher learning. Social design experiments--cultural historical formations designed to promote transformative learning for adults and children--are organized around expansive notions of learning and…

  12. Lifting Off of the Digital Plateau with Military Decision Support Systems

    Science.gov (United States)

    2013-05-23

    whether to commit a reserve element. It is more appropriate to problems such as “diagnosing disease , handling online technical support questions, and...Review Report. Washington, DC: Government Printing Office, 2006. Drudzel, Marek J., and Roger R. Flynn. “Decision Support Systems.” Edited by Allen Kent

  13. A New Method for Lift-off of III-Nitride Semiconductors for Heterogeneous Integration

    Directory of Open Access Journals (Sweden)

    Zang KeYan

    2010-01-01

    Full Text Available Abstract The release and transfer of GaN epilayers to other substrates is of interest for a variety of applications, including heterogeneous integration of silicon logic devices, III–V power devices and optical devices. We have developed a simple wet chemical etching method to release high-quality epitaxial III-nitride films from their substrates. This method builds on a nanoepitaxial lateral overgrowth (NELO process that provides III-Nitride films with low dislocation densities. NELO is accomplished using a nanoporous mask layer patterned on GaN substrates. Chemical removal of the SiO2 layer after growth of III-Nitride overlayers causes fracture at the interface between the GaN film and the original GaN substrate, resulting in free-standing GaN films with nanostructured surfaces on one side. These layers can be transferred to other substrates, and the nano-structured surface can be used in photonic devices, or planarized for power devices.

  14. Effects of Surface Micro-Geometry On the Lift-Off Speed of an EHL Contact

    NARCIS (Netherlands)

    Masen, M.A.; Venner, C.H.; Lugt, P.M.; Tripp, J.H.

    2002-01-01

    With decreasing speed the film thickness in an EHL contact decreases. Below a certain speed asperity contact will take place and gradually the contact enters the mixed lubrication regime. Vice-versa, with increasing speed beyond a certain speed the film thickness has reached a level where asperity c

  15. Lift-Off Processing and Aluminum on Silicon Superconducting Circuit Coherence

    Science.gov (United States)

    Dunsworth, Andrew; Megrant, Anthony; Quintana, Chris; Chen, Zijun; Barends, Rami; Chen, Yu; Fowler, Austin; Jeffrey, Evan; Mutus, Josh; Roushan, Pedram; Sank, Daniel; Hoi, Iochun; Campbell, Brooks; Chiaro, Ben; Kelly, Julian; Neil, Charels; O'Malley, Peter; Vainsencher, Amit; Wenner, Jim; White, Ted; Cleland, Andrew; Martinis, John; Martinis Group Team

    2015-03-01

    Dielctric loss from two level states (TLS's) are a limiting decoherence method in planar superconducting qubits. Previously we have shown that liftoff deposited metal has more loss than etched devices. Current fabrication techniques of Xmon qubit devices limit this loss by using liftoff metal on only a small area of the transmon including the Josephson junctions. However this method leads to excess loss when used on a silicon substrate. I have used quality factor measurments of coplanar waveguide resonator circuits as a tool to measure isolated steps in the liftoff processes. I will report on the effects of these steps and their added loss. This research was funded by the Office of the Director of National Intelligence (ODNI), Intelligence Advanced Research Projects Activity (IARPA), through the Army Research Office Grant JMAR-05.

  16. Seeing Sound - Image Analysis of the Lift-off Acoustic Field Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A launch vehicle and its launch facilities are subjected to intense acoustic loads generated by the vehicle's propulsion system. The vehicle, its payload, and...

  17. Assessment of Microphone Phased Array for Measuring Launch Vehicle Lift-off Acoustics

    Science.gov (United States)

    Garcia, Roberto

    2012-01-01

    The specific purpose of the present work was to demonstrate the suitability of a microphone phased array for launch acoustics applications via participation in selected firings of the Ares I Scale Model Acoustics Test. The Ares I Scale Model Acoustics Test is a part of the discontinued Constellation Program Ares I Project, but the basic understanding gained from this test is expected to help development of the Space Launch System vehicles. Correct identification of sources not only improves the predictive ability, but provides guidance for a quieter design of the launch pad and optimization of the water suppression system. This document contains the results of the NASA Engineering and Safety Center assessment.

  18. Seeing Sound - Image Analysis of the Lift-off Acoustic Field Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A launch vehicle and its launch facilities are subjected to intense acoustic loads generated by the vehicle's propulsion system. The vehicle, its payload, and...

  19. High-Fidelity Prediction of Launch Vehicle Lift-off Acoustic Environment Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Launch vehicles experience extreme acoustic loads during liftoff driven by the interaction of rocket plumes and plume-generated acoustic waves with ground...

  20. Transient Lift-Off Test Results for an Experimental Hybrid Bearing in Air

    Science.gov (United States)

    2009-12-01

    Direction of applied load during bump test .......................................................... 32 Fig. 12 Rotordynamic damped natural frequency map 50... rotordynamic response plot at test bearing 50% Torque-50% Pressure...35 Fig. 15 Rotordynamic damped natural frequency map 25% Torque-25% Pressure......... 36 Fig. 16

  1. Lightweight polypropylene/stainless-steel fiber composite foams with low percolation for efficient electromagnetic interference shielding.

    Science.gov (United States)

    Ameli, Aboutaleb; Nofar, Mohammadreza; Wang, Sai; Park, Chul B

    2014-07-23

    Lightweight polypropylene/stainless-steel fiber (PP-SSF) composites with 15-35% density reduction were fabricated using foam injection molding. The electrical percolation threshold, through-plane electrical conductivity, and electromagnetic interference (EMI) shielding effectiveness (SE) of the PP-SSF composite foams were characterized and compared against the solid counterparts. With 3 wt % CO2 dissolved in PP as a temporary plasticizer and lubricant, the fiber breakage was significantly decreased during injection molding, and well-dispersed fibers with unprecedentedly large aspect ratios of over 100 were achieved. The percolation threshold was dramatically decreased from 0.85 to 0.21 vol %, accounting for 75% reduction, which is highly superior, compared to 28% reduction of the previous PP-carbon fiber composite foam.1 Unlike the case of carbon fiber,1 SSFs were much longer than the cell size, and the percolation threshold reduction of PP-SSF composite foams was thus primarily governed by the decreased fiber breakage instead of fiber orientation. The specific EMI SE was also significantly enhanced. A maximum specific EMI SE of 75 dB·g(-1)·cm(3) was achieved in PP-1.1 vol % SSF composite foams, which was much higher than that of the solid counterpart. Also, the relationships between the microstructure and properties were discussed. The mechanism of EMI shielding enhancement was also studied.

  2. Arnold's Projective Plane and -Matrices

    Directory of Open Access Journals (Sweden)

    K. Uchino

    2010-01-01

    Full Text Available We will explain Arnold's 2-dimensional (shortly, 2D projective geometry (Arnold, 2005 by means of lattice theory. It will be shown that the projection of the set of nontrivial triangular -matrices is the pencil of tangent lines of a quadratic curve on Arnold's projective plane.

  3. Affine Contractions on the Plane

    Science.gov (United States)

    Celik, D.; Ozdemir, Y.; Ureyen, M.

    2007-01-01

    Contractions play a considerable role in the theory of fractals. However, it is not easy to find contractions which are not similitudes. In this study, it is shown by counter examples that an affine transformation of the plane carrying a given triangle onto another triangle may not be a contraction even if it contracts edges, heights or medians.…

  4. Distributed storage in the plane

    NARCIS (Netherlands)

    Altman, Eitan; Avrachenkov, Konstatin; Goseling, Jasper

    2013-01-01

    We consider storage devices located in the plane according to a general point process and specialize the results for the homogeneous Poisson process. A large data file is stored at the storage devices, which have limited storage capabilities. Hence, they can only store parts of the data. Clients can

  5. Distributed storage in the plane

    NARCIS (Netherlands)

    Altman, Eitan; Avrachenkov, Konstatin; Goseling, Jasper

    2014-01-01

    We consider storage devices located in the plane according to a general point process and specialize the results for the homogeneous Poisson process. A large data file is stored at the storage devices, which have limited storage capabilities. Hence, they can only store parts of the data. Clients can

  6. Plane and parabolic solar panels

    CERN Document Server

    Sales, J H O

    2009-01-01

    We present a plane and parabolic collector that absorbs radiant energy and transforms it in heat. Therefore we have a panel to heat water. We study how to increment this capture of solar beams onto the panel in order to increase its efficiency in heating water.

  7. Distributed storage in the plane

    NARCIS (Netherlands)

    Altman, Eitan; Avrachenkov, Konstatin; Goseling, Jasper

    2013-01-01

    We consider storage devices located in the plane according to a general point process and specialize the results for the homogeneous Poisson process. A large data file is stored at the storage devices, which have limited storage capabilities. Hence, they can only store parts of the data. Clients can

  8. Distributed storage in the plane

    NARCIS (Netherlands)

    Altman, Eitan; Avrachenkov, Konstatin; Goseling, Jasper

    2014-01-01

    We consider storage devices located in the plane according to a general point process and specialize the results for the homogeneous Poisson process. A large data file is stored at the storage devices, which have limited storage capabilities. Hence, they can only store parts of the data. Clients can

  9. Brittleness Generation Mechanism and Failure Model of High Strength Lightweight Aggregate Concrete

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The brittleness generation mechanism of high strength lightweight aggregate concrete(HSLWAC) was presented, and it was indicated that lightweight aggregate was the vulnerable spot,initiating brittleness. Based on the analysis of the brittleness failure by the load-deflection curve, the brittleness presented by HSLWAC was more prominent compared with ordinary lightweight aggregate concrete of the same strength grade. The model of brittleness failure was also established.

  10. Chemical Acidic Attack Resistance of Lightweight Concrete with Additives

    Directory of Open Access Journals (Sweden)

    Salwa H. Ahmed

    2013-04-01

    Full Text Available  This research was studied the effect of H2SO4(8% , HCl (8% acidic and wastewaterpH= 5.1, SO4= = 850mg/L, Cl-=750 mg/L , TDS = 2500 mg/L( on the lightweight concrete by using limestone as lightweight aggregate and using the foam material (LightCrete. Super plasticizers (SP also used to enhance the properties of the lightweight concrete. Studying the effect of acidic solution and wastewater was done by calculating the percentage of decrease in weight and compressive strength of concrete prisms (100 * 100 * 400 mm, where the small portion of the flexural modulus test was submerged completely in the above solutions,  and the salt rising was observed by immersion (100 mm depth from the second portion of the prism in the above solutions. اظهرت نتائج الفحوصات ان H 2 SO 4 يكون تأثيره اكثر من HCl بالنسبة للنقصان بالوزن على الخرسانة الاعتيادية  بينما يكون تأثير HCl كبير على الخرسانة خفيفة الوزن بأستخدام الركام خفيف الوزن (Limestone وتأثيره اقل من H 2 SO 4 بالنسبة للخرسانة خفيفة الوزن باستخدام المادة الرغوية . Results show that the H2SO4 have influence larger than HCl for the decrease of weight on the normal concrete while the effect of HCl was larger than H2SO4  on lightweight concrete with limestone and its effect was less than H2SO4 on the lightweight concrete with foam. وكذلك تبين ان تأثير H 2 SO 4 على الخرسانة الاعتيادية بالنسبة للنقصان بالمقاومة يكون اقل من تاثير HCl بينما يكون تاثير H 2 SO 4 كبير على الخرسانة خفيفة الوزن الحاوية على المادة الرغوية وتاثيره اقل على الخرسانة خفيفة الوزن الحاوية على SP و Limestone . The results also shown that the effect of H2SO4 on the normal

  11. Gravitational Couplings for y-Gop-Planes

    CERN Document Server

    Ospina-Giraldo, J F

    2000-01-01

    The Wess-Zumino action for y deformed and generalized orientifold planes (yGOp-planes) is presented and one power expantion is realized from which processes that involves yGOp-planes, RR-forms, gravitons and gaugeons, are obtained. Finally non-standard yGOp-planes are showed.

  12. Cryogenic Piezo Actuators for Lightweight, Large Aperture, Deployable Membrane Mirrors Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Single crystal piezoelectric actuators are proposed to enable large stroke, high precision, shape control for cryogenic lightweight deployable membrane mirror...

  13. Method for calculating thermal properties of lightweight floor heating panels based on an experimental setup

    DEFF Research Database (Denmark)

    Weitzmann, Peter; Svendsen, Svend

    2005-01-01

    Lightweight floor heating systems consist of a plastic tube connected to a heat distribution aluminium plate and are used in wooden floor constructions. The thermal properties of lightweight floor heating systems cannot be described accurately. The reason is a very complex interaction of convection......, radiation and conduction of the heat transfer between pipe and surrounding materials. The European Standard for floor heating, EN1264, does not cover lightweight systems, while the supplemental Nordtest Method VVS127 is aimed at lightweight systems. The thermal properties can be found using tabulated values...

  14. Linear Instability of the Plane Couette and Plane Poiseuille Flows

    CERN Document Server

    Chefranov, Sergey G

    2015-01-01

    We show possibility of the Plane Couette (PC) flow instability for Reynolds number Re>Reth=140. This new result of the linear hydrodynamic stability theory is obtained on the base of refusal from the traditionally used assumption on longitudinal periodicity of the disturbances along the direction of the fluid flow. We found that earlier existing understanding on the linear stability of this flow for any arbitrary large Reynolds number is directly related with an assumption on the separation of the variables of the spatial variability for the disturbance field and their periodicity in linear theory of stability. By the refusal from the pointed assumptions also for the Plane Poiseuille (PP) flow, we get a new threshold Reynolds value Reth=1040 that with 4% accuracy agrees with the experiment contrary to more than 500% discrepancy for the earlier known estimate Reth=5772 obtained in the frame of the linear theory but when using the "normal" disturbance form (S. A. Orszag, 1971).

  15. Large Lightweight Mirrors Controlled by Dielectric Elastomer Artifical Muscle

    Science.gov (United States)

    Kornbluh, R. D.; Flamm, D. S.; Vujkovic-Civijin, P.; Pelrine, R. E.; Huestis, D. L.

    2002-05-01

    We will describe a new concept for control of the lightweight large-aperture mirrors that will be required for future space-based astronomy and remote sensing applications. To be cost effective and practical, such optical systems must be lightweight and capable of deployment from highly compacted stowed configurations. Optical systems based on membrane mirrors or other lightweight structures can address some of these needs, but such flexible gossamer structures present challenges in achieving and maintaining the required shape or figure. For the past 9 years SRI has been exploring dielectric elastomer artifical muscle technology for active control of objects and structures [1-2]. The basic functional element is a thin polymer film coated on both sides by a compliant electrode material. When voltage is applied between the top and bottom electrodes, an electrostrictive compressive force squeezes the film, causing it to expand in area. The induced forces are related to the square of the voltage. If we assemble a large mirror from numerous independently addressable elements, sophisticated control is possible, even including adaptive optics. Dielectric elastomers have many advantages over other electroactive polymers and other smart-materials actuation technologies that have been considered in the past. For example, from many candidate materials we can choose ones with high planar strains, low power dissipation, tolerance of the space environment, and ease of commercial fabrication into large sheets. [1] R. Pelrine, R. Kornbluh, Q. Pei, and J. Joseph, Science 287, 386 (2000). [2] R. Pelrine, P. Sommer-Larson, R. Kornbluh, R. Heydt, G. Kofod, Q. Pei, and P. Gravesen, in Smart Structures and Materials 2001: Electroactive Polymer Actuators and Devices, ed. Y. Bar-Cohen, Proc. SPIE 4329, 335 (2001).

  16. High precision optical finishing of lightweight silicon carbide aspheric mirror

    Science.gov (United States)

    Kong, John; Young, Kevin

    2010-10-01

    Critical to the deployment of large surveillance optics into the space environment is the generation of high quality optics. Traditionally, aluminum, glass and beryllium have been used; however, silicon carbide becomes of increasing interest and availability due to its high strength. With the hardness of silicon carbide being similar to diamond, traditional polishing methods suffer from slow material removal rates, difficulty in achieving the desired figure and inherent risk of causing catastrophic damage to the lightweight structure. Rather than increasing structural capacity and mass of the substrate, our proprietary sub-aperture aspheric surface forming technology offers higher material removal rates (comparable to that of Zerodur or Fused Silica), a deterministic approach to achieving the desired figure while minimizing contact area and the resulting load on the optical structure. The technology performed on computer-controlled machines with motion control software providing precise and quick convergence of surface figure, as demonstrated by optically finishing lightweight silicon carbide aspheres. At the same time, it also offers the advantage of ideal pitch finish of low surface micro-roughness and low mid-spatial frequency error. This method provides a solution applicable to all common silicon carbide substrate materials, including substrates with CVD silicon carbide cladding, offered by major silicon carbide material suppliers. This paper discusses a demonstration mirror we polished using this novel technology. The mirror is a lightweight silicon carbide substrate with CVD silicon carbide cladding. It is a convex hyperbolic secondary mirror with 104mm diameter and approximately 20 microns aspheric departure from best-fit sphere. The mirror has been finished with surface irregularity of better than 1/50 wave RMS @632.8 nm and surface micro-roughness of under 2 angstroms RMS. The technology has the potential to be scaled up for manufacturing capabilities of

  17. A lightweight feedback-controlled microdrive for chronic neural recordings

    Science.gov (United States)

    Jovalekic, A.; Cavé-Lopez, S.; Canopoli, A.; Ondracek, J. M.; Nager, A.; Vyssotski, A. L.; Hahnloser, R. H. R.

    2017-04-01

    Objective. Chronic neural recordings have provided many insights into the relationship between neural activity and behavior. We set out to develop a miniaturized motorized microdrive that allows precise electrode positioning despite possibly unreliable motors. Approach. We designed a feedback-based motor control mechanism. It contains an integrated position readout from an array of magnets and a Hall sensor. Main results. Our extremely lightweight (feedback-based microdrive control requires little extra size and weight, suggesting that such control can be incorporated into more complex multi-electrode designs.

  18. Cryogenic optical tests of a lightweight HIP beryllium mirror

    Science.gov (United States)

    Melugin, Ramsey K.; Miller, Jacob H.; Young, J. A.; Howard, Steven D.; Pryor, G. Mark

    Five interferometric tests were conducted at cryogenic temperatures on a lightweight, 50 cm diameter, hot isostatic pressed (HIP) beryllium mirror in the Ames Research Center (ARC) Cryogenic Optics Test Facility. The purpose of the tests was to determine the stability of the mirror's figure when cooled to cryogenic temperatures. Test temperatures ranged from room ambient to 8 K. One cycle to 8 K and five cycles to 80 K were performed. Optical and thermal test methods are described. Data is presented to show the amount of cryogenic distortion and hysteresis present in the mirror when measured with an earlier, Shack interferometer, and with a newly-acquired, phase-measuring interferometer.

  19. Lightweight Aggregate Concrete. The materials in the precast elements

    DEFF Research Database (Denmark)

    Goltermann, Per; Larsen, Henning; Ingholt, N.U.

    1996-01-01

    The precast lightweight aggregate concrete (LAC) elements are used extensively in Denmark, where the use of precast elements domonates the building structures. Similar elements are used in other parts of Nothern Europe, which have lead to development of an European standard for precast LAC elements...... of LAC with open structure (prEN1520).The test results have shown that the formulas in prEN1520's revision are fairly correct and lead to slightly conservative estimates of the modulus of elasticity and flexural strength....

  20. Lightweight rotor design by optimal spar cap offset

    Science.gov (United States)

    Croce, A.; Sartori, L.; Lunghini, M. S.; Clozza, L.; Bortolotti, P.; Bottasso, C. L.

    2016-09-01

    Bend-twist coupling behavior is induced in a blade by displacing the suction side spar cap towards the leading edge, and the pressure side one in the opposite direction. Additional couplings are introduced by rotating the spar cap fibers. The structural configuration of the blade is optimized using an automated design environment. The resulting blade shows significant benefits in terms of mass and loads when compared to the baseline uncoupled one. Finally, the lightweight design concept is used to increase the rotor size, resulting in a larger energy yield for the same hub loads.

  1. Laser based metal and plastics joining for lightweight design

    Science.gov (United States)

    Kahmann, Max; Quentin, Ulf; Kirchhoff, Marc; Brockmann, Rüdiger; Löffler, Klaus

    2015-03-01

    One of the most important issues in automotive industry is lightweight design, especially since the CO2 emission of new cars has to be reduced by 2020. Plastic and fiber reinforced plastics (e.g. CFRP and GFRP) receive besides new manufacturing methods and the employment of high-strength steels or non-ferrous metals increasing interest. Especially the combination of different materials such as metals and plastics to single components exhausts the entire potential on weight reduction. This article presents an approach based on short laser pulses to join such dissimilar materials in industrial applications.

  2. Light-weight spherical mirrors for Cherenkov detectors

    CERN Document Server

    Cisbani, E; Colilli, S; Crateri, R; Cusanno, F; De Leo, R; Fratoni, R; Frullani, S; Garibaldi, F; Giuliani, F; Gricia, M; Iodice, M; Iommi, R; Lagamba, L; Lucentini, M; Mostarda, A; Nappi, E; Pierangeli, L; Santavenere, F; Urciuoli, G M; Vernin, P

    2003-01-01

    Light-weight spherical mirrors have been appositely designed and built for the gas threshold Cherenkov detectors of the two Hall A spectrometers. The mirrors are made of a 1 mm thick aluminized plexiglass sheet, reinforced by a rigid backing consisting of a phenolic honeycomb sandwiched between two carbon fiber mats epoxy glued. The produced mirrors have a thickness equivalent to 0.55% of radiation length, and an optical slope error of about 5.5 mrad. These characteristics make these mirrors suitable for the implementation in Cherenkov threshold detectors. Ways to improve the mirror features are also discussed in view of their possible employment in RICH detectors.

  3. Vibrations in a Multi-Storey Lightweight Building Structure

    DEFF Research Database (Denmark)

    Andersen, Lars Vabbersgaard; Kirkegaard, Poul Henning

    2013-01-01

    This paper provides a quantification of the changes in vibration level that can be expected in a lightweight multi-storey wooden building due to reduced connection stiffness or added nonstructural mass. Firstly, the impact of changes in the floor-to-wall connections is examined. Secondly, a study...... is performed regarding variations of the vibration level due to different placements of nonstructural mass inside the building. The analyses are carried out by means of a modular three-dimensional finite-element model. Each floor and wall panel is modelled in high detail, including door and window openings...

  4. Lightweight Radioisotope Heater Unit (LWRHU) production for the Cassini mission

    Energy Technology Data Exchange (ETDEWEB)

    Rinehart, G.H.

    1996-06-01

    The Lightweight Radioisotope Heater Unit (LWRHU) is a {sup 238}PuO{sub 2} fueled heat source designed to provide a thermal watt of power for space missions. The LWRHU will be used to maintain the temperature of various components on the spacecraft at the required level. The heat source consists of a {sup 238}PuO{sub 2} fuel pellet, a Pt-30Rh capsule, a pyrolytic graphite insulator, and a woven graphite aeroshell assembly. Los Alamos has fabricated 180 heater units, which will be used on the Cassini mission. This report summarizes the specifications, fabrication processes, and production data for the heat sources fabricated at Los Alamos.

  5. An extremely lightweight fingernail worn prosthetic interface device

    Science.gov (United States)

    Yetkin, Oguz; Ahluwalia, Simranjit; Silva, Dinithi; Kasi-Okonye, Isioma; Volker, Rachael; Baptist, Joshua R.; Popa, Dan O.

    2016-05-01

    Upper limb prosthetics are currently operated using several electromyography sensors mounted on an amputee's residual limb. In order for any prosthetic driving interface to be widely adopted, it needs to be responsive, lightweight, and out of the way when not being used. In this paper we discuss the possibility of replacing such electrodes with fingernail optical sensor systems mounted on the sound limb. We present a prototype device that can detect pinch gestures and communicate with the prosthetic system. The device detects the relative position of fingers to each other by measuring light transmitted via tissue. Applications are not limited to prosthetic control, but can be extended to other human-machine interfaces.

  6. Minimization of structure-borne noise in lightweight buildings

    DEFF Research Database (Denmark)

    Niu, Bin; Olhoff, Niels

    2012-01-01

    This paper deals with the problem of minimizing the structure-borne noise induced in a room by machinery vibration. A generalized system consisting of the machine, the base plate, resilient mounts, the floor plate and the room cavity is developed for analysis and optimization. Topological design...... of the base plate is studied for optimizing machinery installation. Furthermore, periodic mounts are optimized for the noise reduction. Finally, a modular model of a lightweight building is developed for design optimization of dimensions and connections of modules in the building for decreasing machinery...

  7. Model Reduction in Dynamic Finite Element Analysis of Lightweight Structures

    DEFF Research Database (Denmark)

    Flodén, Ola; Persson, Kent; Sjöström, Anders

    2012-01-01

    The application of wood as a construction material when building multi-storey buildings has many advantages, e.g., light weight, sustainability and low energy consumption during the construction and lifecycle of the building. However, compared to heavy structures, it is a greater challenge to build...... lightweight structures without noise and disturbing vibrations between storeys and rooms. The dynamic response of floor and wall structures may be investigated using finite element models with three-dimensional solid elements [1]. In order to analyse the global response of complete buildings, finite element...

  8. Accuracy of Dynamic and Acoustic Analysis of Lightweight Panel Structures

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Dickow, Kristoffer Ahrens; Andersen, Lars Vabbersgaard

    2012-01-01

    in such buildings is important. In the lowfrequency range, prediction of sound and vibration in building structures may be achieved by finite-element analysis (FEA). The aim of this paper is to compare the two commercial codes ABAQUS and ANSYS for FEA of an acoustic-structural coupling in a timber lightweight panel...... structure. For this purpose, modal analyses are carried out employing a fully coupled model of sound waves within an acoustic medium and vibrations in the structural part. The study concerns the frequency range 50–250 Hz....

  9. Lightweight approach to model traceability in a CASE tool

    Science.gov (United States)

    Vileiniskis, Tomas; Skersys, Tomas; Pavalkis, Saulius; Butleris, Rimantas; Butkiene, Rita

    2017-07-01

    A term "model-driven" is not at all a new buzzword within the ranks of system development community. Nevertheless, the ever increasing complexity of model-driven approaches keeps fueling all kinds of discussions around this paradigm and pushes researchers forward to research and develop new and more effective ways to system development. With the increasing complexity, model traceability, and model management as a whole, becomes indispensable activities of model-driven system development process. The main goal of this paper is to present a conceptual design and implementation of a practical lightweight approach to model traceability in a CASE tool.

  10. Lightweight, Efficient Power Converters for Advanced Turboelectric Aircraft Propulsion Systems

    Science.gov (United States)

    Hennessy, Michael J.

    2014-01-01

    NASA is investigating advanced turboelectric aircraft propulsion systems that use superconducting motors to drive multiple distributed turbofans. Conventional electric motors are too large and heavy to be practical for this application; therefore, superconducting motors are required. In order to improve aircraft maneuverability, variable-speed power converters are required to throttle power to the turbofans. The low operating temperature and the need for lightweight components that place a minimum of additional heat load on the refrigeration system open the possibility of incorporating extremely efficient cryogenic power conversion technology. This Phase II project is developing critical components required to meet these goals.

  11. Ultra lightweight mirror performance at 8 degrees kelvin

    Science.gov (United States)

    Crowe, D. A.; Melugin, R. K.; Miller, J. H.

    1985-01-01

    Earlier work funded by DARPA, evaluating the optical stability of a 0.5-m ultra-lightweight, frit-bonded, fused silica mirror, is extended from the previous 100 deg K specification down to 8 deg K. The thermal stability is excellent and comparable to that for conventional fusion and solid mirrors. The total mirror change of 0.10 lambda rms (lambda = 0.6328 microns) meets the needs of most IR systems. Thermal elastic quilting is excellent (0.008 lambda). Ames Research Center and Kodak data evaluations, done independently, are in very good agreement.

  12. On rank 5 projective planes

    Directory of Open Access Journals (Sweden)

    Otto Bachmann

    1984-01-01

    Full Text Available In this paper we continue the study of projective planes which admit collineation groups of low rank (Kallaher [1] and Bachmann [2,3]. A rank 5 collineation group of a projective plane ℙ of order n≠3 is proved to be flag-transitive. As in the rank 3 and rank 4 case this implies that is ℙ not desarguesian and that n is (a prime power of the form m4 if m is odd and n=m2 with m≡0mod4 if n is even. Our proof relies on the classification of all doubly transitive groups of finite degree (which follows from the classification of all finite simple groups.

  13. Hydrodynamics of planing monohull watercraft

    CERN Document Server

    Vorus, William S

    2017-01-01

    This book addresses the principles involved in the design and engineering of planing monohull power boats, with an emphasis on the theoretical fundamentals that readers need in order to be fully functional in marine design and engineering. Author William Vorus focuses on three topics: boat resistance, seaway response, and propulsion and explains the physical principles, mathematical details, and theoretical details that support physical understanding. In particular, he explains the approximations and simplifications in mathematics that lead to success in the applications of planing craft design engineering, and begins with the simplest configuration that embodies the basic physics. He leads readers, step-by-step, through the physical complications that occur, leading to a useful working knowledge of marine design and engineering. Included in the book are a wealth of examples that exemplify some of the most important naval architecture and marine engineering problems that challenge many of today’s engineers.

  14. Plane waves as tractor beams

    CERN Document Server

    Forgács, Péter; Romańczukiewicz, Tomasz

    2013-01-01

    It is shown that in a large class of systems plane waves can act as tractor beams: i.e., an incident plane wave can exert a pulling force on the scatterer. The underlying physical mechanism for the pulling force is due to the sufficiently strong scattering of the incoming wave into another mode having a larger wave number, in which case excess momentum is created behind the scatterer. Such a tractor beam or negative radiation pressure effect arises naturally in systems where the coupling between the scattering channels is due to Aharonov-Bohm (AB) gauge potentials. It is demonstrated that this effect is also present if the AB potential is an induced, ("artificial") gauge potential such as the one found in J. March-Russell, J. Preskill, F. Wilczek, Phys. Rev. Lett. 58 2567 (1992).

  15. Eight plane IPND mechanical testing.

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, A.; Guarino, V.; Wood, K.; Nephew, T.; Ayres, D.; Lee, A.; High Energy Physics; FNAL

    2008-03-18

    A mechanical test of an 8 plane IPND mechanical prototype, which was constructed using extrusions from the testing/tryout of the 16 cell prototype extrusion die in Argonne National Laboratory, was conducted. There were 4 vertical and 4 horizontal planes in this 8 plane IPND prototype. Each vertical plane had four 16 cell extrusions, while each horizontal plane had six 16 cell extrusions. Each plane was glued together using the formulation of Devcon adhesive, Devcon 60. The vertical extrusions used in the vertical planes shares the same dimensions as the horizontal extrusions in the horizontal planes with the average web thickness of 2.1 mm and the average wall thickness of 3.1 mm. This mechanical prototype was constructed with end-seals on the both ends of the vertical extrusions. The gaps were filled with epoxy between extrusions and end-seals. The overall dimension of IPND is 154.8 by 103.1 by 21.7 inches with the weight of approximately 1200 kg, as shown in a figure. Two similar mechanical tests of 3 layer and 11 layer prototypes have been done in order to evaluate the strength of the adhesive joint between extrusions in the NOvA detector. The test showed that the IPND prototype was able to sustain under the loading of weight of itself and scintillator. Two FEA models were built to verify the measurement data from the test. The prediction from FEA slice model seems correlated reasonably well to the test result, even under a 'rough' estimated condition for the wall thickness (from an untuned die) and an unknown property of 'garage type' extrusion. A full size of FEA 3-D model also agrees very well with the test data from strain gage readings. It is worthy to point out that the stress distribution of the structure is predominantly determined by the internal pressure, while the buckling stability relies more on the loading weight from the extrusions themselves and scintillate. Results of conducted internal pressure tests, including 3- cell, 11

  16. Force Lines in Plane Stress

    DEFF Research Database (Denmark)

    Rathkjen, Arne

    A state of plane stress is illustrated by means of two families of curves, each family representing constant values of a derivative of Airy's stress function. The two families of curves form a map giving in the first place an overall picture of regions of high and low stress, and in the second...... place, the map comprises a complete graphic representation of the stress at any point....

  17. Sustainability assessment of a lightweight biomimetic ceiling structure.

    Science.gov (United States)

    Antony, Florian; Grießhammer, Rainer; Speck, Thomas; Speck, Olga

    2014-03-01

    An intensive and continuous debate centres on the question of whether biomimetics has a specific potential to contribute to sustainability. In the context of a case study, the objective of this paper is to contribute to this debate by presenting the first systematic approach to assess the sustainability of a complex biomimetic product. The object of inquiry is a lecture hall's ribbed slab. Based on criteria suggested by the Association of German Engineers (VDI), it has been verified that the slab has been correctly defined as biomimetic. Moreover, a systematic comparative product sustainability assessment has been carefully carried out. For purposes of comparison, estimated static calculations have been performed for conceivable current state-of-the-art lightweight ceiling structures. Alternative options are a hollow article slab and a pre-stressed flat slab. Besides a detailed benefit analysis and a discussion of social effects, their costs have also been compared. A particularly detailed life cycle assessment on the respective environmental impacts has also been performed. Results show that the biomimetic ribbed slab built in the 1960s is able to keep up with the current state-of-the-art lightweight solutions in terms of sustainability. These promising results encourage a systematic search for a broad range of sustainable biomimetic solutions.

  18. Concept for lightweight spaced-based deposition technology

    Energy Technology Data Exchange (ETDEWEB)

    Fulton, Michael; Anders, Andre

    2006-02-28

    In this contribution we will describe a technology path to very high quality coatings fabricated in the vacuum of space. To accomplish the ambitious goals set out in NASA's Lunar-Mars proposal, advanced thin-film deposition technology will be required. The ability to deposit thin-film coatings in the vacuum of lunar-space could be extremely valuable for executing this new space mission. Developing lightweight space-based deposition technology (goal:<300 g, including power supply) will enable the future fabrication and repair of flexible large-area space antennae and fixed telescope mirrors for lunar-station observatories. Filtered Cathodic Arc (FCA) is a proven terrestrial energetic thin-film deposition technology that does not need any processing gas but is well suited for ultra-high vacuum operation. Recently, miniaturized cathodic arcs have already been developed and considered for space propulsion. It is proposed to combine miniaturized pulsed FCA technology and robotics to create a robust, enabling space-based deposition system for the fabrication, improvement, and repair of thin films, especially of silver and aluminum, on telescope mirrors and eventually on large area flexible substrates. Using miniature power supplies with inductive storage, the typical low-voltage supply systems used in space are adequate. It is shown that high-value, small area coatings are within the reach of existing technology, while medium and large area coatings are challenging in terms of lightweight technology and economics.

  19. A novel lightweight Fizeau infrared interferometric imaging system

    Science.gov (United States)

    Hope, Douglas A.; Hart, Michael; Warner, Steve; Durney, Oli; Romeo, Robert

    2016-05-01

    Aperture synthesis imaging techniques using an interferometer provide a means to achieve imagery with spatial resolution equivalent to a conventional filled aperture telescope at a significantly reduced size, weight and cost, an important implication for air- and space-borne persistent observing platforms. These concepts have been realized in SIRII (Space-based IR-imaging interferometer), a new light-weight, compact SWIR and MWIR imaging interferometer designed for space-based surveillance. The sensor design is configured as a six-element Fizeau interferometer; it is scalable, light-weight, and uses structural components and main optics made of carbon fiber replicated polymer (CFRP) that are easy to fabricate and inexpensive. A three-element prototype of the SIRII imager has been constructed. The optics, detectors, and interferometric signal processing principles draw on experience developed in ground-based astronomical applications designed to yield the highest sensitivity and resolution with cost-effective optical solutions. SIRII is being designed for technical intelligence from geo-stationary orbit. It has an instantaneous 6 x 6 mrad FOV and the ability to rapidly scan a 6x6 deg FOV, with a minimal SNR. The interferometric design can be scaled to larger equivalent filled aperture, while minimizing weight and costs when compared to a filled aperture telescope with equivalent resolution. This scalability in SIRII allows it address a range of IR-imaging scenarios.

  20. Thermal performance of lightweight construction systems: Performance of `Solar One`

    Energy Technology Data Exchange (ETDEWEB)

    Hyde, R. [Queensland Univ., St. Lucia, QLD (Australia)

    1995-12-31

    Research is currently under way to asses the thermal performance of building which use new lightweight systems of construction. In particular, comparison is made between expected performance and performance found in buildings. This paper outlines the basic direction of the research and examines one particular building case study, that of Solar One. Solar One is located at Mount Coolum to the north of Brisbane on the Sunshine Coast in Queensland. This building is designed based on climatic criteria and departs from the conventional timber framed house in a number of respects. The important difference in this building is that it is a hybrid construction. Mass is used for some walls and ground floor slab and timber framing with fibre-cement for other walls. The research demonstrates to what extent the building performs to characteristics of lightweight construction systems and to what extent it performs as a heavyweight system. Focus is placed on the thermal response of the building. Conclusions reached from this case study suggest that the building does not match expected patterns of thermal response particularly in winter, there appears to be a complex heat interchange process showing clear benefits for the hybrid construction. (author). 10 figs., 4 refs.

  1. Coating Thin Mirror Segments for Lightweight X-ray Optics

    Science.gov (United States)

    Chan, Kai-Wing; Sharpe, Marton V.; Zhang, William; Kolosc, Linette; Hong, Melinda; McClelland, Ryan; Hohl, Bruce R.; Saha, Timo; Mazzarellam, James

    2013-01-01

    Next generations lightweight, high resolution, high throughput optics for x-ray astronomy requires integration of very thin mirror segments into a lightweight telescope housing without distortion. Thin glass substrates with linear dimension of 200 mm and thickness as small as 0.4 mm can now be fabricated to a precision of a few arc-seconds for grazing incidence optics. Subsequent implementation requires a distortion-free deposition of metals such as iridium or platinum. These depositions, however, generally have high coating stresses that cause mirror distortion. In this paper, we discuss the coating stress on these thin glass mirrors and the effort to eliminate their induced distortion. It is shown that balancing the coating distortion either by coating films with tensile and compressive stresses, or on both sides of the mirrors is not sufficient. Heating the mirror in a moderately high temperature turns out to relax the coated films reasonably well to a precision of about a second of arc and therefore provide a practical solution to the coating problem.

  2. Apply lightweight recognition algorithms in optical music recognition

    Science.gov (United States)

    Pham, Viet-Khoi; Nguyen, Hai-Dang; Nguyen-Khac, Tung-Anh; Tran, Minh-Triet

    2015-02-01

    The problems of digitalization and transformation of musical scores into machine-readable format are necessary to be solved since they help people to enjoy music, to learn music, to conserve music sheets, and even to assist music composers. However, the results of existing methods still require improvements for higher accuracy. Therefore, the authors propose lightweight algorithms for Optical Music Recognition to help people to recognize and automatically play musical scores. In our proposal, after removing staff lines and extracting symbols, each music symbol is represented as a grid of identical M ∗ N cells, and the features are extracted and classified with multiple lightweight SVM classifiers. Through experiments, the authors find that the size of 10 ∗ 12 cells yields the highest precision value. Experimental results on the dataset consisting of 4929 music symbols taken from 18 modern music sheets in the Synthetic Score Database show that our proposed method is able to classify printed musical scores with accuracy up to 99.56%.

  3. a Light-Weight Laser Scanner for Uav Applications

    Science.gov (United States)

    Tommaselli, A. M. G.; Torres, F. M.

    2016-06-01

    Unmanned Aerial Vehicles (UAV) have been recognized as a tool for geospatial data acquisition due to their flexibility and favourable cost benefit ratio. The practical use of laser scanning devices on-board UAVs is also developing with new experimental and commercial systems. This paper describes a light-weight laser scanning system composed of an IbeoLux scanner, an Inertial Navigation System Span-IGM-S1, from Novatel, a Raspberry PI portable computer, which records data from both systems and an octopter UAV. The performance of this light-weight system was assessed both for accuracy and with respect to point density, using Ground Control Points (GCP) as reference. Two flights were performed with the UAV octopter carrying the equipment. In the first trial, the flight height was 100 m with six strips over a parking area. The second trial was carried out over an urban park with some buildings and artificial targets serving as reference Ground Control Points. In this experiment a flight height of 70 m was chosen to improve target response. Accuracy was assessed based on control points the coordinates of which were measured in the field. Results showed that vertical accuracy with this prototype is around 30 cm, which is acceptable for forest applications but this accuracy can be improved using further refinements in direct georeferencing and in the system calibration.

  4. A LIGHT-WEIGHT LASER SCANNER FOR UAV APPLICATIONS

    Directory of Open Access Journals (Sweden)

    A. M. G. Tommaselli

    2016-06-01

    Full Text Available Unmanned Aerial Vehicles (UAV have been recognized as a tool for geospatial data acquisition due to their flexibility and favourable cost benefit ratio. The practical use of laser scanning devices on-board UAVs is also developing with new experimental and commercial systems. This paper describes a light-weight laser scanning system composed of an IbeoLux scanner, an Inertial Navigation System Span-IGM-S1, from Novatel, a Raspberry PI portable computer, which records data from both systems and an octopter UAV. The performance of this light-weight system was assessed both for accuracy and with respect to point density, using Ground Control Points (GCP as reference. Two flights were performed with the UAV octopter carrying the equipment. In the first trial, the flight height was 100 m with six strips over a parking area. The second trial was carried out over an urban park with some buildings and artificial targets serving as reference Ground Control Points. In this experiment a flight height of 70 m was chosen to improve target response. Accuracy was assessed based on control points the coordinates of which were measured in the field. Results showed that vertical accuracy with this prototype is around 30 cm, which is acceptable for forest applications but this accuracy can be improved using further refinements in direct georeferencing and in the system calibration.

  5. Efficient Hardware Implementation of the Lightweight Block Encryption Algorithm LEA

    Directory of Open Access Journals (Sweden)

    Donggeon Lee

    2014-01-01

    Full Text Available Recently, due to the advent of resource-constrained trends, such as smartphones and smart devices, the computing environment is changing. Because our daily life is deeply intertwined with ubiquitous networks, the importance of security is growing. A lightweight encryption algorithm is essential for secure communication between these kinds of resource-constrained devices, and many researchers have been investigating this field. Recently, a lightweight block cipher called LEA was proposed. LEA was originally targeted for efficient implementation on microprocessors, as it is fast when implemented in software and furthermore, it has a small memory footprint. To reflect on recent technology, all required calculations utilize 32-bit wide operations. In addition, the algorithm is comprised of not complex S-Box-like structures but simple Addition, Rotation, and XOR operations. To the best of our knowledge, this paper is the first report on a comprehensive hardware implementation of LEA. We present various hardware structures and their implementation results according to key sizes. Even though LEA was originally targeted at software efficiency, it also shows high efficiency when implemented as hardware.

  6. Optical fabrication of lightweighted 3D printed mirrors

    Science.gov (United States)

    Herzog, Harrison; Segal, Jacob; Smith, Jeremy; Bates, Richard; Calis, Jacob; De La Torre, Alyssa; Kim, Dae Wook; Mici, Joni; Mireles, Jorge; Stubbs, David M.; Wicker, Ryan

    2015-09-01

    Direct Metal Laser Sintering (DMLS) and Electron Beam Melting (EBM) 3D printing technologies were utilized to create lightweight, optical grade mirrors out of AlSi10Mg aluminum and Ti6Al4V titanium alloys at the University of Arizona in Tucson. The mirror prototypes were polished to meet the λ/20 RMS and λ/4 P-V surface figure requirements. The intent of this project was to design topologically optimized mirrors that had a high specific stiffness and low surface displacement. Two models were designed using Altair Inspire software, and the mirrors had to endure the polishing process with the necessary stiffness to eliminate print-through. Mitigating porosity of the 3D printed mirror blanks was a challenge in the face of reconciling new printing technologies with traditional optical polishing methods. The prototypes underwent Hot Isostatic Press (HIP) and heat treatment to improve density, eliminate porosity, and relieve internal stresses. Metal 3D printing allows for nearly unlimited topological constraints on design and virtually eliminates the need for a machine shop when creating an optical quality mirror. This research can lead to an increase in mirror mounting support complexity in the manufacturing of lightweight mirrors and improve overall process efficiency. The project aspired to have many future applications of light weighted 3D printed mirrors, such as spaceflight. This paper covers the design/fab/polish/test of 3D printed mirrors, thermal/structural finite element analysis, and results.

  7. A Lightweight Structure Redesign Method Based on Selective Laser Melting

    Directory of Open Access Journals (Sweden)

    Li Tang

    2016-11-01

    Full Text Available The purpose of this paper is to present a new design method of lightweight parts fabricated by selective laser melting (SLM based on the “Skin-Frame” and to explore the influence of fabrication defects on SLM parts with different sizes. Some standard lattice parts were designed according to the Chinese GB/T 1452-2005 standard and manufactured by SLM. Then these samples were tested in an MTS Insight 30 compression testing machine to study the trends of the yield process with different structure sizes. A set of standard cylinder samples were also designed according to the Chinese GB/T 228-2010 standard. These samples, which were made of iron-nickel alloy (IN718, were also processed by SLM, and then tested in the universal material testing machine INSTRON 1346 to obtain their tensile strength. Furthermore, a lightweight redesigned method was researched. Then some common parts such as a stopper and connecting plate were redesigned using this method. These redesigned parts were fabricated and some application tests have already been performed. The compression testing results show that when the minimum structure size is larger than 1.5 mm, the mechanical characteristics will hardly be affected by process defects. The cylinder parts were fractured by the universal material testing machine at about 1069.6 MPa. These redesigned parts worked well in application tests, with both the weight and fabrication time of these parts reduced more than 20%.

  8. Reactive Commercial Ni/Al Nanolayers for Joining Lightweight Alloys

    Science.gov (United States)

    Simões, Sónia; Viana, Filomena; Vieira, Manuel F.

    2014-05-01

    Reactive nanoscale multilayer foils for use in joining techniques have attracted a great deal of attention. A common feature of these nanolayers is the large amount of heat released during the reaction between the layers to form a new phase. In this study, films of alternated Ni and Al nanolayers (NanoFoil® made by the Indium Corporation) with period (bilayer thickness) close to 54 nm and with a thickness of 60 μm were used as local heat sources to bond lightweight alloys. The as-deposited Ni and Al alternated nanolayers evolve into NiAl nanometric grains when the multilayer, ignited by an electrical discharge, reacts. Joining of lightweight alloys was performed at room temperature under pressures of 10-80 MPa. The ability of the nanolayers to join these alloys by high temperature diffusion bonding was also investigated. The microstructural and chemical characterizations of the interfaces were performed on cross-sections of the joints by scanning electron microscopy and energy dispersive x-ray spectroscopy. Ni/Al nanolayers are an effective means of joining titanium alloys at room temperature. A sound interface, mainly composed by NiAl grains, is obtained in joints of TiAl/TiAl and TiAl/Inconel, produced with NanoFoil® by annealing at 700 ºC, during 60 min under a pressure of 10 MPa. The low shear strength revealed a weak adhesion of the nanofoil to the base materials.

  9. Lightweight storage and overlay networks for fault tolerance.

    Energy Technology Data Exchange (ETDEWEB)

    Oldfield, Ron A.

    2010-01-01

    The next generation of capability-class, massively parallel processing (MPP) systems is expected to have hundreds of thousands to millions of processors, In such environments, it is critical to have fault-tolerance mechanisms, including checkpoint/restart, that scale with the size of applications and the percentage of the system on which the applications execute. For application-driven, periodic checkpoint operations, the state-of-the-art does not provide a scalable solution. For example, on today's massive-scale systems that execute applications which consume most of the memory of the employed compute nodes, checkpoint operations generate I/O that consumes nearly 80% of the total I/O usage. Motivated by this observation, this project aims to improve I/O performance for application-directed checkpoints through the use of lightweight storage architectures and overlay networks. Lightweight storage provide direct access to underlying storage devices. Overlay networks provide caching and processing capabilities in the compute-node fabric. The combination has potential to signifcantly reduce I/O overhead for large-scale applications. This report describes our combined efforts to model and understand overheads for application-directed checkpoints, as well as implementation and performance analysis of a checkpoint service that uses available compute nodes as a network cache for checkpoint operations.

  10. Application of lightweight threading techniques to computational chemistry

    Science.gov (United States)

    Thornley, John; Muller, Richard P.; Mainz, Daniel T.; Çağin, Tahir; Goddard, William A.

    2001-05-01

    The recent advent of inexpensive commodity multiprocessor computers with standardized operating system support for lightweight threads provides computational chemists and other scientists with an exciting opportunity to develop sophisticated new approaches to materials simulation. We contrast the flexible performance characteristics of lightweight threading with the restrictions of traditional scientific supercomputing, based on our experiences with multithreaded molecular dynamics simulation. Motivated by the results of our molecular dynamics experiments, we propose an approach to multi-scale materials simulation using highly dynamic thread creation and synchronization within and between concurrent simulations at many different scales. This approach will enable extremely realistic simulations, with computing resources dynamically directed to areas where they are needed. Multi-scale simulations of this kind require large amounts of processing power, but are too sophisticated to be expressed using traditional supercomputing programming models. As a result, we have developed a high-level programming system called Sthreads that allows highly dynamic, nested multithreaded algorithms to be expressed. Program development is simplified through the use of innovative synchronization operations that allow multithreaded programs to be tested and debugged using standard sequential methods and tools. For this reason, Sthreads is very well suited to the complex multi-scale simulation applications that we are developing.

  11. Lightweight Provenance Service for High-Performance Computing

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Dong; Chen, Yong; Carns, Philip; Jenkins, John; Ross, Robert

    2017-09-09

    Provenance describes detailed information about the history of a piece of data, containing the relationships among elements such as users, processes, jobs, and workflows that contribute to the existence of data. Provenance is key to supporting many data management functionalities that are increasingly important in operations such as identifying data sources, parameters, or assumptions behind a given result; auditing data usage; or understanding details about how inputs are transformed into outputs. Despite its importance, however, provenance support is largely underdeveloped in highly parallel architectures and systems. One major challenge is the demanding requirements of providing provenance service in situ. The need to remain lightweight and to be always on often conflicts with the need to be transparent and offer an accurate catalog of details regarding the applications and systems. To tackle this challenge, we introduce a lightweight provenance service, called LPS, for high-performance computing (HPC) systems. LPS leverages a kernel instrument mechanism to achieve transparency and introduces representative execution and flexible granularity to capture comprehensive provenance with controllable overhead. Extensive evaluations and use cases have confirmed its efficiency and usability. We believe that LPS can be integrated into current and future HPC systems to support a variety of data management needs.

  12. Average density and porosity of high-strength lightweight concrete

    Directory of Open Access Journals (Sweden)

    A.S. Inozemtcev

    2014-11-01

    Full Text Available The analysis results of high-strength lightweight concrete (HSLWC structure are presented in this paper. The X-ray tomography, optical microscopy and other methods are used for researching of average density and porosity. It has been revealed that mixtures of HSLWC with density 1300…1500 kg/m3 have a homogeneous structure. The developed concrete has a uniform distribution of the hollow filler and a uniform layer of cement-mineral matrix. The highly saturated gas phase which is divided by denser large particles of quartz sand and products of cement hydration in the contact area allow forming a composite material with low average density, big porosity (up to 40% and high strength (compressive strength is more than 40 MPa. Special modifiers increase adhesion, compacts structure in the contact area, decrease water absorption of high-strength lightweight concrete (up to 1 % and ensure its high water resistance (water resistance coefficient is more than 0.95.

  13. Lightweight C/SiC mirrors for space application

    Science.gov (United States)

    Zhou, Hao; Zhang, Chang-rui; Cao, Ying-bin; Zhou, Xin-gui

    2006-02-01

    Challenges in high resolution space telescopes have led to the desire to create large primary mirror apertures. Ceramic mirrors and complex structures are becoming more important for high precision lightweight optical applications in adverse environments. Carbon-fiber reinforced silicon carbide (C/SiC) has shown great potential to be used as mirror substrate. This material has a high stiffness to weight ratio, dimensional stability from ambient to cryo temperatures, and thermal conductivity, low thermal expansion as well. These properties make C/SiC very attractive for a variety of applications in precision optical structures, especially when considering space-borne application. In this paper, lightweight C/SiC mirror prepared for a scan mirror of a high resolution camera is presented. The manufacturing of C/SiC mirror starts with a porous rigid felt made of short chopped carbon fibers. The fibers are molded with phenolic resin under pressure to form a carbon fiber reinforced plastic blank, followed by a pyrolization process by which the phenolic resin reacts to a carbon matrix. The C/C-felt can be machined by standard computer controlled milling techniques to any virtual shape. This is one of the most significant advantages of this material, as it drastically reduces the making costs and enables the manufacture of truly ultra-lightweight mirrors, reflectors and structures. Upon completion of milling, the C/C-felt preform is mounted in a high-temperature furnace together with silicon and heated under vacuum condition to 1500°C at which the silicon changes into liquid phase. Subsequently, the molten silicon is infiltrated into the porous preform under capillary forces to react with carbon matrix and the surfaces of the carbon fibers to form a density C/SiC substrate. The C/SiC material retains the preform shape to within a tight tolerance after sintering means the ceramization process is a nearly net shaping process. Reactive melt infiltrated C/SiC, followed by

  14. Analysis and trade-off studies of large lightweight mirror structures. [large space telescope

    Science.gov (United States)

    Soosaar, K.; Grin, R.; Ayer, F.

    1975-01-01

    A candidate mirror, hexagonally lightweighted, is analyzed under various loadings using as complete a procedure as possible. Successive simplifications are introduced and compared to an original analysis. A model which is a reasonable compromise between accuracy and cost is found and is used for making trade-off studies of the various structural parameters of the lightweighted mirror.

  15. 46 CFR 170.200 - Estimated lightweight vertical center of gravity.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Estimated lightweight vertical center of gravity. 170... Centers of Gravity § 170.200 Estimated lightweight vertical center of gravity. (a) Each tank vessel that... calculations required by §§ 170.170 and 172.065, the vertical center of gravity of a tank vessel in the...

  16. 77 FR 73615 - Lightweight Thermal Paper From Germany; Preliminary Results of Antidumping Duty Administrative...

    Science.gov (United States)

    2012-12-11

    ...] Lightweight Thermal Paper From Germany; Preliminary Results of Antidumping Duty Administrative Review; 2010... duty order on lightweight thermal paper (LWTP) from Germany for the period November 1, 2010, through... sales of subject merchandise at less than normal value, based on adverse facts available (AFA). DATES...

  17. Lightweight ZERODUR®: A Candidate Material for Affordable Future UVOIR Space Telescopes of All Apertures

    Science.gov (United States)

    Hull, Anthony B.; Westerhoff, T.; Leys, A.

    2014-01-01

    Recent Developments now make available for spaceborne applications highly lightweighted mirrors in ZERODUR®, regarded to be the “gold standard” material for thermal stability. ZERODUR® has flown on over 30 missions, including two great observatories, but not previously to this high degree of lightweighting. Now highly lightweighted mirror substrates can be made from a single billet of low expansion glass which exhibits remarkably low thermal expansion, anisotropy and inhomogeneity. This staility has the potential to simplify every aspect of a mission payload cost. A 1.2m open-back isogrid lightweighted mirror substrate has been made by SCHOTT exhibiting 88% lightweighting and a first Eigenfrequency over 200Hz. Also a recently made 0.3m isogrid lightweighted mirror exhibits ribs thinner than 0.9mm. Mirror or mirror segment substrates can be cost-effectively manufactured from monolithic blanks in apertures as small as 0.3m aperture to over 4m aperture (until recently SCHOTT maintained a line to make 8m ZERODUR® billets). We will describe this technology, the attributes of isogrid lightweighted mirror blanks, and the relevance of this material and manufacturing approach to upcoming UVOIR missions from suborbital to Explorer class to next generation Great Observatory. Lightweight ZERODUR® supports optical telescope systems requiring great stability, even in the presence of payload and scene thermal perturbations. Furthermore, mirrors or mirror segments made with the approach described can be made to remarkably short schedule, cost effectively and with little risk.

  18. 78 FR 43142 - Lightweight Thermal Paper From the People's Republic of China: Rescission of Antidumping Duty...

    Science.gov (United States)

    2013-07-19

    ... High-Tech Co., Ltd.; Henan Province Jianghe Paper Co., Ltd., Jianghe Paper Co., Ltd., and JHT Paper... wrap, a non-subject product) and 4811.90.8040 (for ``other'' including lightweight thermal paper... product) and 4811.90.9090 (for ``other,'' including lightweight thermal paper). \\8\\ As of January 1,...

  19. Method for calculating thermal properties of lightweight floor heating panels based on an experimental setup

    DEFF Research Database (Denmark)

    Weitzmann, Peter; Svendsen, Svend

    2005-01-01

    Lightweight floor heating systems consist of a plastic tube connected to a heat distribution aluminium plate and are used in wooden floor constructions. The thermal properties of lightweight floor heating systems cannot be described accurately. The reason is a very complex interaction of convecti...

  20. 78 FR 23220 - Lightweight Thermal Paper From Germany: Final Results of Antidumping Duty Administrative Review...

    Science.gov (United States)

    2013-04-18

    ... International Trade Administration Lightweight Thermal Paper From Germany: Final Results of Antidumping Duty... from Germany.\\1\\ The period of review (POR) is November 1, 2010, through October 31, 2011. We invited... in the section entitled ``Final Results of Review.'' \\1\\ See Lightweight Thermal Paper from...

  1. EFFECTS OF LIGHTWEIGHT MULLITE-SILICA RICH GLASS COMPOSITE AGGREGATES ON PROPERTIES OF CASTABLES

    Directory of Open Access Journals (Sweden)

    Li Y.

    2013-09-01

    Full Text Available Mullite-silica rich glass (MSRG composite is a material which is more efficient than chamotte for refractory utilization of clay. The effects of lightweight MSRG composite aggregate on the properties of refractory castables were studied by XRD, SEM and EDS, etc. Comparing with a common lightweight chamotte aggregate, it was found that the hot modulus of rupture, refractoriness under load and thermal shock resistance of the castable with lightweight MSRG aggregate were higher than those of the castable with a common lightweight chamotte aggregate because MSRG did not contain silica crystalline phases and contained a liquid phase with very high viscosity at high temperature. The castables with lightweight chamotte aggregate have higher thermal expansion because of existence of cristobalite and quartz, and have lower thermal conductivity because of higher porosity.

  2. Properties of Structural Lightweight Concrete Filled with Palm-Based Polyurethane

    Directory of Open Access Journals (Sweden)

    Kamarul Aini Mohd Sari

    2014-09-01

    Full Text Available Four experiments were conducted to characterize the properties of palm-based polyurethane (PU foam in lightweight concrete. The PU foam was synthesized from palm kernel oil-based polyol reacted with 2, 4-methylene diphenyl diisocyanate. Polyurethane as lightweight aggregate was mixed with ordinary cement, sand, and water to form lightweight concrete. The microstructure of PU aggregate can be accessed from optical micrographs. Density, compressive strength, distribution of fine aggregate, and the interfacial zone were also investigated. The result showed that palm-based lightweight concrete has excellent compressive strength (17.5 MPa, and fulfilled the minimum strength requirement for structural concrete. Palm-based lightweight concrete with 0.6 w/c ratio and 3% w/w PU system achieved 1770 kg/m3 presented uniform dispersion of aggregate and excellent mechanical bonding.

  3. Physical property of basic unit and database in machine tool lightweight design%机床轻量化设计基本单元物理性能与数据库的研究

    Institute of Scientific and Technical Information of China (English)

    董惠敏; 邢俏芳; 王德胜; 姜怀胜; 王德伦; 申会鹏; 孙颖

    2012-01-01

    To provide the scientific basis for mac.hine tool structure lightweight design, the machine tool lightweight unit design technology is explored. The structure performance of panel-type unit is investigated. The basic unit database for the machine tool lightweight design is constructed. Through researching the internal structure feature of machine tool components in practical engineering application, the concept of lightweight panel-type unit is proposed. Seven kinds of plane-type basic units are abstracted, and the plane-type basic unit spectrum is established. Based on ANSYS finite element analysis method, the seven kinds of parametric physical models with plane-type basic unit are built. In the situation of basic unit with same dimension parameters or same mass, the static and dynamic performances of seven kinds of plane-type basic units are studied respectively. The static property of each kind of basic unit in pull, press, bend and twist, as well as the dynamic base frequency distribution rule are obtained, which provides the data sources for the machine tool lightweight database.%探讨机床轻量化单元设计技术,研究壁板类单元的结构性能,构建机床轻量化设计基本单元数据库,为机床支承件轻量化设计提供科学依据.通过研究实际工程应用中机床支承件的内部结构特征,提出机床轻量化壁板类单元概念,抽象出7种壁板类基本单元,建立壁板类基本单元型谱.基于AN-SYS有限元分析方法,建立7种壁板类基本单元的参数化物理模型.在基本单元尺度参数和质量相同情况下,分别研究了7种壁板类基本单元的静动态性能.得到各种基本单元的拉、压、弯、扭静态性能,以及动态基频分布规律,为机床轻量化数据库提供数据来源.

  4. SNAP Satellite Focal Plane Development

    Energy Technology Data Exchange (ETDEWEB)

    Bebek, C.; Akerlof, C.; Aldering, G.; Amanullah, R.; Astier, P.; Baltay, C.; Barrelet, E.; Basa, S.; Bercovitz, J.; Bergstrom, L.; Berstein, G.P.; Bester, M.; Bohlin, R.; Bonissent, A.; Bower, C.; Campbell, M.; Carithers, W.; Commins, E.; Day, C.; Deustua, S.; DiGennaro, R.; Ealet, A.; Ellis, R.; Emmett, W.; Eriksson, M.; Fouchez,D.; Fruchter, A.; Genat, J-F.; Goldhaber, G.; Goobar, A.; Groom, D.; Heetderks, H.; Holland, S.; Huterer, D.; Johnson, W.; Kadel, R.; Karcher,A.; Kim, A.; Kolbe, W.; Lafever, R.; Lamoureaux, J.; Lampton, M.; Lefevre, O.; Levi, M.; Levin, D.; Linder, E.; Loken, S.; Malina, R.; Mazure, A.; McKay, T.; McKee, S.; Miquel, R.; Morgan, N.; Mortsell, E.; Mostek, N.; Mufson, S.; Musser, J.; Roe, N.; Nugent, P.; Oluseyi, H.; Pain, R.; Palaio, N.; Pankow, D.; Perlmutter, S.; Prieto, E.; Rabinowitz,D.; Refregier, A.; Rhodes, J.; Schubnell, M.; Sholl, M.; Smadja, G.; Smith, R.; Smoot, G.; Snyder, J.; Spadafora, A.; Szymkowiak, A.; Tarle,G.; Taylor, K.; Tilquin, A.; Tomasch, A.; Vincent, D.; von der Lippe, H.; Walder, J-P.; Wang, G.

    2003-07-07

    The proposed SuperNova/Acceleration Probe (SNAP) mission will have a two-meter class telescope delivering diffraction-limited images to an instrumented 0.7 square degree field in the visible and near-infrared wavelength regime. The requirements for the instrument suite and the present configuration of the focal plane concept are presented. A two year R&D phase, largely supported by the Department of Energy, is just beginning. We describe the development activities that are taking place to advance our preparedness for mission proposal in the areas of detectors and electronics.

  5. On free fermions and plane partitions

    CERN Document Server

    Foda, O; Zuparic, M

    2008-01-01

    We use free fermion methods to re-derive a result of Okounkov and Reshetikhin relating charged fermions to random plane partitions, and to extend it to relate neutral fermions to strict plane partitions.

  6. The Micro-Instrumentation Package: A Solution to Lightweight Ballooning

    Science.gov (United States)

    Juneau, Jill

    This paper discusses the design and testing of an over the horizon (OTH) light weight telemetry and termination system that can be used for small ballooning payloads. Currently, the Columbia Scientific Balloon Facility (CSBF) provides telemetry for the science payload by integrating one of two types of support packages. The type of support package integrated depends on whether the flight will stay in range of line of sight (LOS) or will exceed LOS requiring the use of over the horizon (OTH) telemetry. The weights of these systems range from 100 pounds to 350 pounds depending upon the use of redundant systems, equipment for high data rates, and batteries and/or solar panels for power requirements. These weight values are not as significant for larger payloads but can be crippling for smaller payloads. In addition, these support package systems are fairly expensive, placing a high importance on recovery. A lightweight and inexpensive telemetry system could be beneficial for various reasons. First, it would allow scientists to fly lightweight payloads on large balloons reaching even higher altitudes. Second, scientists could fly lightweight payloads on less expensive balloons such as meteorological balloons. Depending on the payload, these flights could be fairly inexpensive and even disposable. Third, a compact telemetry system on any balloon will free up more room for the science portion of the payload. In response, a compact telemetry/termination system called the Micro-Instrumentation Package (MIP) was developed. The MIP provides uplink and downlink communications, an interface to the science, housekeeping information including global positioning system (GPS) position, and relays. Instead of a power-hungry microprocessor, the MIP's central consists of a microcontroller. Microcontrollers are lower power, easily programmed, and can be purchased for less than ten dollars. For uplink and downlink telemetry, the MIP uses an LOS serial transceiver and an Iridium unit

  7. Energy reduction through voltage scaling and lightweight checking

    Science.gov (United States)

    Kadric, Edin

    As the semiconductor roadmap reaches smaller feature sizes and the end of Dennard Scaling, design goals change, and managing the power envelope often dominates delay minimization. Voltage scaling remains a powerful tool to reduce energy. We find that it results in about 60% geomean energy reduction on top of other common low-energy optimizations with 22nm CMOS technology. However, when voltage is reduced, it becomes easier for noise and particle strikes to upset a node, potentially causing Silent Data Corruption (SDC). The 60% energy reduction, therefore, comes with a significant drop in reliability. Duplication with checking and triple-modular redundancy are traditional approaches used to combat transient errors, but spending 2--3x the energy for redundant computation can diminish or reverse the benefits of voltage scaling. As an alternative, we explore the opportunity to use checking operations that are cheaper than the base computation they are guarding. We devise a classification system for applications and their lightweight checking characteristics. In particular, we identify and evaluate the effectiveness of lightweight checks in a broad set of common tasks in scientific computing and signal processing. We find that the lightweight checks cost only a fraction of the base computation (0-25%) and allow us to recover the reliability losses from voltage scaling. Overall, we show about 50% net energy reduction without compromising reliability compared to operation at the nominal voltage. We use FPGAs (Field-Programmable Gate Arrays) in our work, although the same ideas can be applied to different systems. On top of voltage scaling, we explore other common low-energy techniques for FPGAs: transmission gates, gate boosting, power gating, low-leakage (high-Vth) processes, and dual-V dd architectures. We do not scale voltage for memories, so lower voltages help us reduce logic and interconnect energy, but not memory energy. At lower voltages, memories become dominant

  8. Lightweight and Statistical Techniques for Petascale PetaScale Debugging

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Barton

    2014-06-30

    This project investigated novel techniques for debugging scientific applications on petascale architectures. In particular, we developed lightweight tools that narrow the problem space when bugs are encountered. We also developed techniques that either limit the number of tasks and the code regions to which a developer must apply a traditional debugger or that apply statistical techniques to provide direct suggestions of the location and type of error. We extend previous work on the Stack Trace Analysis Tool (STAT), that has already demonstrated scalability to over one hundred thousand MPI tasks. We also extended statistical techniques developed to isolate programming errors in widely used sequential or threaded applications in the Cooperative Bug Isolation (CBI) project to large scale parallel applications. Overall, our research substantially improved productivity on petascale platforms through a tool set for debugging that complements existing commercial tools. Previously, Office Of Science application developers relied either on primitive manual debugging techniques based on printf or they use tools, such as TotalView, that do not scale beyond a few thousand processors. However, bugs often arise at scale and substantial effort and computation cycles are wasted in either reproducing the problem in a smaller run that can be analyzed with the traditional tools or in repeated runs at scale that use the primitive techniques. New techniques that work at scale and automate the process of identifying the root cause of errors were needed. These techniques significantly reduced the time spent debugging petascale applications, thus leading to a greater overall amount of time for application scientists to pursue the scientific objectives for which the systems are purchased. We developed a new paradigm for debugging at scale: techniques that reduced the debugging scenario to a scale suitable for traditional debuggers, e.g., by narrowing the search for the root-cause analysis

  9. Bed form dynamics in distorted lightweight scale models

    Science.gov (United States)

    Aberle, Jochen; Henning, Martin; Ettmer, Bernd

    2016-04-01

    The adequate prediction of flow and sediment transport over bed forms presents a major obstacle for the solution of sedimentation problems in alluvial channels because bed forms affect hydraulic resistance, sediment transport, and channel morphodynamics. Moreover, bed forms can affect hydraulic habitat for biota, may introduce severe restrictions to navigation, and present a major problem for engineering structures such as water intakes and groynes. The main body of knowledge on the geometry and dynamics of bed forms such as dunes originates from laboratory and field investigations focusing on bed forms in sand bed rivers. Such investigations enable insight into the physics of the transport processes, but do not allow for the long term simulation of morphodynamic development as required to assess, for example, the effects of climate change on river morphology. On the other hand, this can be achieved through studies with distorted lightweight scale models allowing for the modification of the time scale. However, our understanding of how well bed form geometry and dynamics, and hence sediment transport mechanics, are reproduced in such models is limited. Within this contribution we explore this issue using data from investigations carried out at the Federal Waterways and Research Institute in Karlsruhe, Germany in a distorted lightweight scale model of the river Oder. The model had a vertical scale of 1:40 and a horizontal scale of 1:100, the bed material consisted of polystyrene particles, and the resulting dune geometry and dynamics were measured with a high spatial and temporal resolution using photogrammetric methods. Parameters describing both the directly measured and up-scaled dune geometry were determined using the random field approach. These parameters (e.g., standard deviation, skewness, kurtosis) will be compared to prototype observations as well as to results from the literature. Similarly, parameters describing the lightweight bed form dynamics, which

  10. 75 FR 41439 - Lightweight Thermal Paper from Germany: Extension of Time Limits for the Preliminary Results of...

    Science.gov (United States)

    2010-07-16

    ... International Trade Administration Lightweight Thermal Paper from Germany: Extension of Time Limits for the... antidumping duty order on lightweight thermal paper from Germany (LTWP), covering the period November 20, 2008... cost of production. See Lightweight Thermal Paper from Germany: Notice of Preliminary Determination...

  11. 76 FR 22078 - Lightweight Thermal Paper From Germany: Notice of Final Results of the First Antidumping Duty...

    Science.gov (United States)

    2011-04-20

    ... International Trade Administration Lightweight Thermal Paper From Germany: Notice of Final Results of the First... administrative review for the antidumping duty order on lightweight thermal paper from Germany.\\2\\ The review... October 31, 2009. \\1\\ See Lightweight Thermal Paper from Germany: Notice of Partial Rescission...

  12. Image plane sweep volume illumination.

    Science.gov (United States)

    Sundén, Erik; Ynnerman, Anders; Ropinski, Timo

    2011-12-01

    In recent years, many volumetric illumination models have been proposed, which have the potential to simulate advanced lighting effects and thus support improved image comprehension. Although volume ray-casting is widely accepted as the volume rendering technique which achieves the highest image quality, so far no volumetric illumination algorithm has been designed to be directly incorporated into the ray-casting process. In this paper we propose image plane sweep volume illumination (IPSVI), which allows the integration of advanced illumination effects into a GPU-based volume ray-caster by exploiting the plane sweep paradigm. Thus, we are able to reduce the problem complexity and achieve interactive frame rates, while supporting scattering as well as shadowing. Since all illumination computations are performed directly within a single rendering pass, IPSVI does not require any preprocessing nor does it need to store intermediate results within an illumination volume. It therefore has a significantly lower memory footprint than other techniques. This makes IPSVI directly applicable to large data sets. Furthermore, the integration into a GPU-based ray-caster allows for high image quality as well as improved rendering performance by exploiting early ray termination. This paper discusses the theory behind IPSVI, describes its implementation, demonstrates its visual results and provides performance measurements.

  13. The INTEGRAL Galactic Plane Scanning

    CERN Document Server

    Fiocchi, Mariateresa

    2013-01-01

    After the first nine years of INTEGRAL operational life, the discovery of new sources and source types, a large fraction of which are highly transient or highly absorbed, is certainly one of the most compelling results and legacies of INTEGRAL. Frequent monitoring of the Galactic Plane in AO8 and AO9 campaigns allowed us to detect transient sources, both known and new, confirming that the gamma-ray sky is dominated by the extreme variability of different classes of objects. Regular scans of the Galactic Plane by INTEGRAL provide the most sensitive hard X-ray wide survey to date of our Galaxy, with flux limits of the order of 0.3 mCrab for an exposure time of ~2Ms. Many transient sources have been detected on a wide range of time scales (~hours to months) and identified by triggered followup observations, mainly by Swift/XRT and optical/infrared telescopes. These discoveries are very important to characterize the X-ray binary population in our Galaxy, that is necessary input for evolution studies. The transien...

  14. The HAWC Galactic Plane Survey

    Science.gov (United States)

    Hui, Michelle

    2016-03-01

    The High Altitude Water Cherenkov (HAWC) Observatory is an all-sky surveying instrument that covers 2/3 of the sky in 24 hours. It is designed with an emphasis on continuous sky coverage for transient events, and on the measurement of extended and large-scale structures. The array is located in Sierra Negra, Mexico at an elevation of 4,100 m and was inaugurated in March 2015. The HAWC array consists of 300 water Cherenkov detectors and is sensitive to extensive air showers triggered by cosmic rays and gamma rays from 100 GeV to >100 TeV. Thanks to its modular design, data taking began in Summer 2013 with 1/3 of the array. Analysis of the first year of data with the partial array shows detections that are coincident with known TeV supernova remnants and pulsar wind nebulae along the Galactic plane. Spectral and morphological analyses are ongoing to study the particle population and acceleration mechanism of these objects. With a growing data set taken with the completed array, source searches are underway for both point-like and extended emission along the Galactic plane, which contain many objects such as pulsar wind nebulae, young star clusters, and binaries.

  15. Lines, Circles, Planes and Spheres

    CERN Document Server

    Purdy, George B

    2009-01-01

    Let $S$ be a set of $n$ points in $\\mathbb{R}^3$, no three collinear and not all coplanar. If at most $n-k$ are coplanar and $n$ is sufficiently large, the total number of planes determined is at least $1 + k \\binom{n-k}{2}-\\binom{k}{2}(\\frac{n-k}{2})$. For similar conditions and sufficiently large $n$, (inspired by the work of P. D. T. A. Elliott in \\cite{Ell67}) we also show that the number of spheres determined by $n$ points is at least $1+\\binom{n-1}{3}-t_3^{orchard}(n-1)$, and this bound is best possible under its hypothesis. (By $t_3^{orchard}(n)$, we are denoting the maximum number of three-point lines attainable by a configuration of $n$ points, no four collinear, in the plane, i.e., the classic Orchard Problem.) New lower bounds are also given for both lines and circles.

  16. Singularities from colliding plane gravitational waves

    Science.gov (United States)

    Tipler, Frank J.

    1980-12-01

    A simple geometrical argument is given which shows that a collision between two plane gravitational waves must result in singularities. The argument suggests that these singularities are a peculiar feature of plane waves, because singularities are also a consequence of a collision between self-gravitating plane waves of other fields with arbitrarily small energy density.

  17. Singularities from colliding plane gravitational waves

    Energy Technology Data Exchange (ETDEWEB)

    Tipler, F.J.

    1980-12-15

    A simple geometrical argument is given which shows that a collision between two plane gravitational waves must result in singularities. The argument suggests that these singularities are a peculiar feature of plane waves, because singularities are also a consequence of a collision between self-gravitating plane waves of other fields with arbitrarily small energy density.

  18. Evolved stars in galactic plane surveys

    NARCIS (Netherlands)

    Verbeek, K.

    2013-01-01

    For the first time in history the entire Galactic Plane is digitally mapped from La Palma and Chile by the European Galactic Plane surveys EGAPS (UVEX, IPHAS and VPHAS+, see http://www.uvexsurvey.org http://www.iphas.org and http://www.vphasplus.org). The complete Galactic plane (3600 square degrees

  19. Homogeneity and plane-wave limits

    CERN Document Server

    Figueroa-O'Farrill, J M; Philip, S; Farrill, Jos\\'e Figueroa-O'; Meessen, Patrick; Philip, Simon

    2005-01-01

    We explore the plane-wave limit of homogeneous spacetimes. For plane-wave limits along homogeneous geodesics the limit is known to be homogeneous and we exhibit the limiting metric in terms of Lie algebraic data. This simplifies many calculations and we illustrate this with several examples. We also investigate the behaviour of (reductive) homogeneous structures under the plane-wave limit.

  20. Lightweight performance data collectors 2.0 with Eiger support.

    Energy Technology Data Exchange (ETDEWEB)

    Allan, Benjamin A.

    2013-05-01

    We report on the use and design of a portable, extensible performance data collection tool motivated by modeling needs of the high performance computing systems co-design com- munity. The lightweight performance data collectors with Eiger support is intended to be a tailorable tool, not a shrink-wrapped library product, as pro ling needs vary widely. A single code markup scheme is reported which, based on compilation ags, can send perfor- mance data from parallel applications to CSV les, to an Eiger mysql database, or (in a non-database environment) to at les for later merging and loading on a host with mysql available. The tool supports C, C++, and Fortran applications.

  1. Lightweight Mechanical Metamaterials with Tunable Negative Thermal Expansion.

    Science.gov (United States)

    Wang, Qiming; Jackson, Julie A; Ge, Qi; Hopkins, Jonathan B; Spadaccini, Christopher M; Fang, Nicholas X

    2016-10-21

    Ice floating on water is a great manifestation of negative thermal expansion (NTE) in nature. The limited examples of natural materials possessing NTE have stimulated research on engineered structures. Previous studies on NTE structures were mostly focused on theoretical design with limited experimental demonstration in two-dimensional planar geometries. In this work, aided with multimaterial projection microstereolithography, we experimentally fabricate lightweight multimaterial lattices that exhibit significant negative thermal expansion in three directions and over a temperature range of 170 degrees. Such NTE is induced by the structural interaction of material components with distinct thermal expansion coefficients. The NTE can be tuned over a large range by varying the thermal expansion coefficient difference between constituent beams and geometrical arrangements. Our experimental results match qualitatively with a simple scaling law and quantitatively with computational models.

  2. Alumina lightweight ceramics modified with plasma synthesized nanopowders

    Science.gov (United States)

    Zake, I.; Svinka, R.; Svinka, V.; Palcevskis, E.

    2011-12-01

    The aim of this study is to clarify possibilities of using plasma synthesized Al2O3 and SiC nanopowders as additives in alumina lightweight ceramics prepared by slip casting. Each plasma synthesized nanopowder (PSNP) was incorporated in the material by a different method, because of their diverse influence on the properties of slip. Al2O3 PSNP was introduced in the matrix in form of aqueous suspension. SiC nanopowder was added directly to raw materials. Bending strength, bulk density, apparent porosity and thermal shock resistance were determined to evaluate the influence of these additives. The effect of Al2O3 PSNP addition on the properties of material depends on the initial sintering temperature. SiC particles during sintering oxidize into SiO2 and then in the reaction with alumina form mullite. Addition of SiC considerably improves bending strength and thermal shock resistance.

  3. Lightweight Interactions for Reciprocal Cooperation in a Social Network Game

    CERN Document Server

    Takano, Masanori; Fukuda, Ichiro

    2016-01-01

    The construction of reciprocal relationships requires cooperative interactions during the initial meetings. However, cooperative behavior with strangers is risky because the strangers may be exploiters. In this study, we show that people increase the likelihood of cooperativeness of strangers by using lightweight non-risky interactions in risky situations based on the analysis of a social network game (SNG). They can construct reciprocal relationships in this manner. The interactions involve low-cost signaling because they are not generated at any cost to the senders and recipients. Theoretical studies show that low-cost signals are not guaranteed to be reliable because the low-cost signals from senders can lie at any time. However, people used low-cost signals to construct reciprocal relationships in an SNG, which suggests the existence of mechanisms for generating reliable, low-cost signals in human evolution.

  4. The 3D lightweight structural characteristics of the beetle forewing.

    Science.gov (United States)

    Chen, Jinxiang; Tuo, Wanyong; Guo, Zhensheng; Yan, Lili

    2017-02-01

    The present paper renewedly expounds upon the characteristics of the 3D lightweight structure of beetle forewings and notes that two biomimetic structures (models) that have appeared in recent years do not comply with these characteristics based on a comparison of the structures of the biological prototypes. The first model features transverse tubules based on observations of circular holes in cross-sectional figures of the Cybister forewing. The second is a biomimetic spherical cavity model with hollow trabeculae that reportedly exhibits superior mechanical properties because its structures are most similar to the biological prototype. Finally, a false biomimetic proposition that the mechanical properties of biomimetic structures with "fiber winding" patterns are superior to those of structures constructed of pure "epoxy" is also noted. Hopefully, the present study can serve to improve the state of research on biomimetic applications of beetle forewing structures.

  5. Lightweight Mechanical Metamaterials with Tunable Negative Thermal Expansion

    Science.gov (United States)

    Wang, Qiming; Jackson, Julie A.; Ge, Qi; Hopkins, Jonathan B.; Spadaccini, Christopher M.; Fang, Nicholas X.

    2016-10-01

    Ice floating on water is a great manifestation of negative thermal expansion (NTE) in nature. The limited examples of natural materials possessing NTE have stimulated research on engineered structures. Previous studies on NTE structures were mostly focused on theoretical design with limited experimental demonstration in two-dimensional planar geometries. In this work, aided with multimaterial projection microstereolithography, we experimentally fabricate lightweight multimaterial lattices that exhibit significant negative thermal expansion in three directions and over a temperature range of 170 degrees. Such NTE is induced by the structural interaction of material components with distinct thermal expansion coefficients. The NTE can be tuned over a large range by varying the thermal expansion coefficient difference between constituent beams and geometrical arrangements. Our experimental results match qualitatively with a simple scaling law and quantitatively with computational models.

  6. Lightweight Phishing URLs Detection Using N-gram Features

    Directory of Open Access Journals (Sweden)

    Ammar Yahya Daeef

    2016-06-01

    Full Text Available Phishing is a kind of attack that belongs to social engineering and this attack seeks to trick people in order to let them reveal their confidential information. Several methods are introduced to detect phishing websites by using different types of features. Unfortunately, these techniques implemented for specific attack vector such as detecting phishing emails which make implementing wide scope detection system crucial demand. URLs analysis proved to be a strong method to detect malicious attacks by previous researches. This technique uses various URL features such as host information, lexical, and other type of features. In this paper, we present wide scope and lightweight phishing detection system using lexical features only. The proposed classifier provides accuracy of 93% with 0.12 second processing time per URL.

  7. Robustness of Modal Parameter Estimation Methods Applied to Lightweight Structures

    DEFF Research Database (Denmark)

    Dickow, Kristoffer Ahrens; Kirkegaard, Poul Henning; Andersen, Lars Vabbersgaard

    2013-01-01

    of nominally identical test subjects. However, the literature on modal testing of timber structures is rather limited and the applicability and robustness of dierent curve tting methods for modal analysis of such structures is not described in detail. The aim of this paper is to investigate the robustness....... The ability to handle closely spaced modes and broad frequency ranges is investigated for a numerical model of a lightweight junction under dierent signal-to-noise ratios. The selection of both excitation points and response points are discussed. It is found that both the Rational Fraction Polynomial-Z method...... of two parameter estimation methods built into the commercial modal testing software B&K Pulse Re ex Advanced Modal Analysis. The investigations are done by means of frequency response functions generated from a nite-element model and subjected to articial noise before being analyzed with Pulse Re ex...

  8. SCIENTIFIC AND TECHNICAL PRECONDITIONS FOR EXTRUDED LIGHTWEIGHT CEMENT SYSTEMS

    Directory of Open Access Journals (Sweden)

    Oreshkin Dmitriy Vladimirovich

    2012-10-01

    The paper also presents the results of the research of the microstructure of spilt Portland cement and hollow glass spheres, their mineral and chemical analyses, as well as the properties of masonry mortars. The paper presents a conclusion that their high process-dependent parameters and superior operating performance are attainable through the introduction of effective hollow glass spheres into masonry mortars and the application of the extrusion method. The aforementioned novelties may reduce the water consumption rate, improve the strength, freeze resistance and durability of cement mortars. The preparation of this paper involved the study of nine reference books. This paper is the first one of a series of papers covering the method of extrusion of lightweight cement mortars.

  9. A Light-Weight Communication Library for Distributed Computing

    CERN Document Server

    Groen, Derek; Grosso, Paola; de Laat, Cees; Zwart, Simon Portegies; 10.1088/1749-4699/3/1/015002

    2010-01-01

    We present MPWide, a platform independent communication library for performing message passing between computers. Our library allows coupling of several local MPI applications through a long distance network and is specifically optimized for such communications. The implementation is deliberately kept light-weight, platform independent and the library can be installed and used without administrative privileges. The only requirements are a C++ compiler and at least one open port to a wide area network on each site. In this paper we present the library, describe the user interface, present performance tests and apply MPWide in a large scale cosmological N-body simulation on a network of two computers, one in Amsterdam and the other in Tokyo.

  10. Thermal conductivity of newspaper sandwiched aerated lightweight concrete panel

    Energy Technology Data Exchange (ETDEWEB)

    Ng, Soon-Ching; Low, Kaw-Sai [Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Jalan Genting Kelang, Setapak, 53300 Kuala Lumpur, Wilayah Persekutuan (Malaysia)

    2010-12-15

    Investigation on the thermal conductivity of newspaper sandwiched aerated lightweight concrete (ALC) panels is the main purpose of this study. Various densities of ALC panels ranging from 1700, 1400 and 1100 kg/m{sup 3} with three different aerial intensities of newspaper sandwiched were produced. Investigation was limited to the effect of aerial intensity of newspaper sandwiched and the effect of density of ALC on thermal conductivity. It is found that the thermal conductivity of newspaper sandwiched ALC panels reduced remarkably compared to control ALC panels. The reduction was recorded at 18.0%, 21.8% and 20.7% correspond to densities of 1700, 1400 and 1100 kg/m{sup 3} with just a mere 0.05 g/cm{sup 2} aerial intensity of newspaper sandwiched. Newspaper sandwiched has a significant impact on the performance of thermal conductivity of ALC panels based on regression analysis. (author)

  11. Research on the Mo del of a Lightweight Resource Addressing

    Institute of Scientific and Technical Information of China (English)

    LUO Bingqing; SUN Zhixin

    2015-01-01

    This paper discussed the characteristics of addressing from the perspective of Internet address-ing mechanism. An Internet of things (IOT) resource ad-dressing iteration model was defined. In the model, a di-rect addressing mode for active nodes and an indirect addressing mode for passive codes were proposed, which meet the requirement for multiple encoding mode. A uni-fied IOT resource lightweight addressing scheme based on IPv6 has been proposed to implement the two addressing modes. The scheme utilized the virtual domain to solve the problem of the heterogeneous encoding. The paper imple-mented the addressing process from the Internet host to the sensor node based on IPv6 over low-power wireless personal area networks (6LoWPAN) protocol. The experi-ment results show that the scheme is performed to realize communication between wireless sensor networks and IPv6 networks.

  12. Vibration Transmission in a Multi-Storey Lightweight Building

    DEFF Research Database (Denmark)

    Niu, Bin; Andersen, Lars Vabbersgaard; Kiel, Nikolaj

    2012-01-01

    This paper develops a parametric modelling and analysis approach to investigate the vibration transmission in lightweight buildings. The main focus of the research is to investigate the influence of geometry and configuration of the building on the vibration transmission. A building with a single......, vibro-acoustic analysis is performed by means of a simple version of the model, where the entire building is constructed by translation and combination of uniform basic modular elements, i.e. wall and floor panels. Each room is created by choosing the component modules from a predefined group of panels...... the modelling of different connections between panels in the building [2]. Using this parametric building model, free vibration analysis is first performed to obtain the distribution of Eigen frequencies of the building. Then the forced vibration of the building subjected to a mechanical excitation is analysed...

  13. Modification of Lightweight Aggregates’ Microstructure by Used Motor Oil Addition

    Directory of Open Access Journals (Sweden)

    Małgorzata Franus

    2016-10-01

    Full Text Available An admixture of lightweight aggregate substrates (beidellitic clay containing 10 wt % of natural clinoptilolite or Na-P1 zeolite with used motor oil (1 wt %–8 wt % caused marked changes in the aggregates’ microstructure, measured by a combination of mercury porosimetry (MIP, microtomography (MT, and scanning electron microscopy. Maximum porosity was produced at low (1%–2% oil concentrations and it dropped at higher concentrations, opposite to the aggregates’ bulk density. Average pore radii, measured by MIP, decreased with an increasing oil concentration, whereas larger (MT pore sizes tended to increase. Fractal dimension, derived from MIP data, changed similarly to the MIP pore radius, while that derived from MT remained unaltered. Solid phase density, measured by helium pycnometry, initially dropped slightly and then increased with the amount of oil added, which was most probably connected to changes in the formation of extremely small closed pores that were not available for He atoms.

  14. A Lightweight, User-controlled System For The Home

    Directory of Open Access Journals (Sweden)

    Lynne Baillie

    2006-01-01

    Full Text Available This paper explores how we designed, with input from some elderly persons, a multi-agent user-controlled network for the home. The system was designed to support the elderly in living longer at home with minimal support. We describe how our work attempts to tackle issues such as privacy, control of personal space, and enjoyment within the home. As the number of elderly individuals’ increases, a certain amount of information gathering or support may be required to assist the elderly in their homes. However, we strongly believe that we should preserve people’s privacy in their homes and ensure that any artifact we propose is seen as enjoyable, aesthetically pleasing and, most importantly, not stigmatizing. We describe in this paper how a lightweight setup, using a multimodal mobile robot, a PDA, and an interactive television, can assist the elderly in the home in an enjoyable and unobtrusive way.

  15. Vibration Transmission in a Multi-Storey Lightweight Building

    DEFF Research Database (Denmark)

    Niu, Bin; Andersen, Lars Vabbersgaard; Kiel, Nikolaj

    2012-01-01

    This paper develops a parametric modelling and analysis approach to investigate the vibration transmission in lightweight buildings. The main focus of the research is to investigate the influence of geometry and configuration of the building on the vibration transmission. A building with a single...... to investigate the transmission of vibration. The influence of different excitation frequencies on the vibration transmission is studied and discussed. The vibration response in two different receiving rooms, one near the source and one far from the source, is illustrated and discussed for the various geometric...... in vibration transmission in a building. The influence on the flanking transmission of introducing a neighbouring room in the direction along the building or on top of the building is discussed. •The vibration transmission in buildings with different room sizes is analyzed and discussed. Based on the parameter...

  16. The use of spent glauconite in lightweight aggregate production

    Directory of Open Access Journals (Sweden)

    Franus, Wojciech

    2011-08-01

    Full Text Available The presented work has shown an application of spent glauconite bed after purification of wastewater for production of lightweight expanded clay aggregates. Sewage, from which it was removed Zn ions, came from technological line (zincworks of Communication Equipment Factory „PZL” Świdnik. Spent glauconite bed was used as an additive in lightweight aggregate production which was obtained using plastic method by sintering, at temperature 1140 ºC and 1200 ºC, of spent glauconite amouts 10, 15, 20 and 25% wt. with clays from open-cast mine „Budy Mszczonowskie”. The presence of the mineral improves sinter texture, increases porosity and contributes to formation of glassy layer on the surface of the aggregates. Tests of zinc elution from lightweight of aggregate samples has shown very low mobility of zinc ions. Content of zinc in water extracts obtained from lightweight of aggregate is definitely lower than zinc concentration permitted for sewage discharge to water or soil, means that spent material is not offensive for the environment as it can be used as a high quality building product.

    El trabajo presentado ha demostrado una aplicación de agotado depósito de glauconita después de la purificación de aguas residuales para la producción de áridos ligeros de arcilla expandida. Las aguas residuales, de la que fueron eliminados los iones Zn, vinieron de la línea tecnológica del equipo de comunicación de la fábrica “PZL” Świdnik. Agotado depósito de glauconita se utiliza como aditivo en la producción de áridos ligeros que se obtuvo utilizando el método de plástico de la sinterización, a temperatura C. 1140 º y 1200 º C, de spent glauconita amouts10, 15, 20 y 25% en peso. con arcillas de la mina a cielo abierto “Budy Mszczonowskie”. La presencia de este mineral mejora la textura de sinterización, aumenta la porosidad y contribuye a la formación de la capa vítrea en la superficie de los agregados. Pruebas de

  17. Lightweight link dimensioning using sFlow sampling

    DEFF Research Database (Denmark)

    de Oliviera Schmidt, Ricardo; Sadre, Ramin; Sperotto, Anna

    2013-01-01

    not be trivial in high-speed links. Aiming scalability, operators often deploy packet sampling on monitoring, but little is known how it affects link dimensioning. In this paper we assess the feasibility of lightweight link dimensioning using sFlow, which is a widely-deployed traffic monitoring tool. We...... implement sFlow sampling algorithm and use a previously proposed and validated dimensioning formula that needs traffic variance. We validate our approach using packet captures from real networks. Results show that the proposed procedure is successful for a range of sampling rates and that, due to randomness...... of sampling algorithm, the error introduced by scaling the traffic variance yields more conservative results that cope with short-term traffic fluctuations....

  18. LPKI - A Lightweight Public Key Infrastructure for the Mobile Environments

    CERN Document Server

    Toorani, Mohsen; 10.1109/ICCS.2008.4737164

    2010-01-01

    The non-repudiation as an essential requirement of many applications can be provided by the asymmetric key model. With the evolution of new applications such as mobile commerce, it is essential to provide secure and efficient solutions for the mobile environments. The traditional public key cryptography involves huge computational costs and is not so suitable for the resource-constrained platforms. The elliptic curve-based approaches as the newer solutions require certain considerations that are not taken into account in the traditional public key infrastructures. The main contribution of this paper is to introduce a Lightweight Public Key Infrastructure (LPKI) for the constrained platforms such as mobile phones. It takes advantages of elliptic curve cryptography and signcryption to decrease the computational costs and communication overheads, and adapting to the constraints. All the computational costs of required validations can be eliminated from end-entities by introduction of a validation authority to th...

  19. Lightweight Mutual Authentication Protocol for Low Cost RFID Tags

    CERN Document Server

    Ahmed, Eslam Gamal; Hashem, Mohamed; 10.5121/ijnsa.2010.2203

    2010-01-01

    Radio Frequency Identification (RFID) technology one of the most promising technologies in the field of ubiquitous computing. Indeed, RFID technology may well replace barcode technology. Although it offers many advantages over other identification systems, there are also associated security risks that are not easy to be addressed. When designing a real lightweight authentication protocol for low cost RFID tags, a number of challenges arise due to the extremely limited computational, storage and communication abilities of Low-cost RFID tags. This paper proposes a real mutual authentication protocol for low cost RFID tags. The proposed protocol prevents passive attacks as active attacks are discounted when designing a protocol to meet the requirements of low cost RFID tags. However the implementation of the protocol meets the limited abilities of low cost RFID tags.

  20. Lightweight Distance bound Protocol for Low Cost RFID Tags

    CERN Document Server

    Ahmed, Eslam Gamal; Hashem, Mohamed

    2010-01-01

    Almost all existing RFID authentication schemes (tag/reader) are vulnerable to relay attacks, because of their inability to estimate the distance to the tag. These attacks are very serious since it can be mounted without the notice of neither the reader nor the tag and cannot be prevented by cryptographic protocols that operate at the application layer. Distance bounding protocols represent a promising way to thwart relay attacks, by measuring the round trip time of short authenticated messages. All the existing distance bounding protocols use random number generator and hash functions at the tag side which make them inapplicable at low cost RFID tags. This paper proposes a lightweight distance bound protocol for low cost RFID tags. The proposed protocol based on modified version of Gossamer mutual authentication protocol. The implementation of the proposed protocol meets the limited abilities of low-cost RFID tags.

  1. Lightweight high temperature test furnace. 21st century technology

    Energy Technology Data Exchange (ETDEWEB)

    De Groot, F.C.

    2004-02-01

    A new high-temperature lightweight furnace design offers potential energy savings, thus reducing emissions and costs, and improves product quality. The Gasunie Research 12 m3 test furnace results are: 36% less heat needed to heat up the furnace; first tests show that 18% of flue gas heat loss is saved through pulse/pause firing; reduced carbon dioxide and gaseous hydrogen fluorides (HF) emissions; improved temperature homogeneity in product batch enables higher throughput; new dust-free combination of Refractory Ceramic Fibres (RCFs) have been tested successfully up to 1250C; new high-temperature vitreous wool (RCFs) with high solubility in body fluids and hence no hazard classification has been successfully tested; furnace control system developed and tested with good results, based on a standard industrial PLC, within stringent gas safety requirements.

  2. Optical Fibres Contactless Sensor for Dynamic Testing of Lightweight Structures

    Directory of Open Access Journals (Sweden)

    L. Bregant

    2008-01-01

    Full Text Available With dynamic testing, engineers describe activities focused on the identification of some properties of vibrating structures. This step requires for the measurements of excitations and responses signals, applying appropriate sensors directly on the test article. These instruments modify the system's mass and stiffness distributions and eventually the eigen-properties of the structure. These errors become unacceptable especially when testing lightweight structures. This paper shows the results of some tests performed on a small compressor with the purpose of identifying the blades’ natural frequencies and modes. It compares the acquisitions performed with standard accelerometers and two different contact-less systems using as exciters either a micro-hammer or a micro inertial shaker. The paper shows how the contact-less sensors provide good quality data and consistent results in the mode identification phase.

  3. An Ultra-Lightweight Encryption Scheme in Underwater Acoustic Networks

    Directory of Open Access Journals (Sweden)

    Chunyan Peng

    2016-01-01

    Full Text Available We tackle a fundamental security problem in underwater acoustic networks (UANs. The S-box in the existing block encryption algorithm is more energy consuming and unsuitable for resources-constrained UANs. In this paper, instead of S-box, we present a lightweight, 8-round iteration block cipher algorithm for UANs communication based on chaotic theory and increase the key space by changing the number of iteration round. We further propose secure network architecture of UANs. By analysis, our algorithm can resist brute-force searches and adversarial attacks. Simulation results show that, compared with traditional AES-128 and PRESENT algorithms, our cryptographic algorithm can make a good trade-off between security and overhead, has better energy efficiency, and applies to UANs.

  4. Image Encryption Using a Lightweight Stream Encryption Algorithm

    Directory of Open Access Journals (Sweden)

    Saeed Bahrami

    2012-01-01

    Full Text Available Security of the multimedia data including image and video is one of the basic requirements for the telecommunications and computer networks. In this paper, we consider a simple and lightweight stream encryption algorithm for image encryption, and a series of tests are performed to confirm suitability of the described encryption algorithm. These tests include visual test, histogram analysis, information entropy, encryption quality, correlation analysis, differential analysis, and performance analysis. Based on this analysis, it can be concluded that the present algorithm in comparison to A5/1 and W7 stream ciphers has the same security level, is better in terms of the speed of performance, and is used for real-time applications.

  5. A Lightweight Distributed Solution to Content Replication in Mobile Networks

    CERN Document Server

    La, Chi-Anh; Casetti, Claudio; Chiasserini, Carla-Fabiana; Fiore, Marco

    2009-01-01

    Performance and reliability of content access in mobile networks is conditioned by the number and location of content replicas deployed at the network nodes. Facility location theory has been the traditional, centralized approach to study content replication: computing the number and placement of replicas in a network can be cast as an uncapacitated facility location problem. The endeavour of this work is to design a distributed, lightweight solution to the above joint optimization problem, while taking into account the network dynamics. In particular, we devise a mechanism that lets nodes share the burden of storing and providing content, so as to achieve load balancing, and decide whether to replicate or drop the information so as to adapt to a dynamic content demand and time-varying topology. We evaluate our mechanism through simulation, by exploring a wide range of settings and studying realistic content access mechanisms that go beyond the traditional assumptionmatching demand points to their closest con...

  6. AEGIS: A Lightweight Firewall for Wireless Sensor Networks

    Science.gov (United States)

    Hossain, Mohammad Sajjad; Raghunathan, Vijay

    Firewalls are an essential component in today's networked computing systems (desktops, laptops, and servers) and provide effective protection against a variety of over-the-network security attacks. With the development of technologies such as IPv6 and 6LoWPAN that pave the way for Internet-connected embedded systems and sensor networks, these devices will soon be subject to (and need to be defended against) similar security threats. As a first step, this paper presents Aegis, a lightweight, rule-based firewall for networked embedded systems such as wireless sensor networks. Aegis is based on a semantically rich, yet simple, rule definition language. In addition, Aegis is highly efficient during operation, runs in a transparent manner from running applications, and is easy to maintain. Experimental results obtained using real sensor nodes and cycle-accurate simulations demonstrate that Aegis successfully performs gatekeeping of a sensor node's communication traffic in a flexible manner with minimal overheads.

  7. Properties of lightweight cement-based composites containing waste polypropylene

    Science.gov (United States)

    Záleská, Martina; Pavlíková, Milena; Pavlík, Zbyšek

    2016-07-01

    Improvement of buildings thermal stability represents an increasingly important trend of the construction industry. This work aims to study the possible use of two types of waste polypropylene (PP) for the development of lightweight cement-based composites with enhanced thermal insulation function. Crushed PP waste originating from the PP tubes production is used for the partial replacement of silica sand by 10, 20, 30, 40 and 50 mass%, whereas a reference mixture without plastic waste is studied as well. First, basic physical and thermal properties of granular PP random copolymer (PPR) and glass fiber reinforced PP (PPGF) aggregate are studied. For the developed composite mixtures, basic physical, mechanical, heat transport and storage properties are accessed. The obtained results show that the composites with incorporated PP aggregate exhibit an improved thermal insulation properties and acceptable mechanical resistivity. This new composite materials with enhanced thermal insulation function are found to be promising materials for buildings subsoil or floor structures.

  8. A Lightweight Approach to Performance Portability with targetDP

    CERN Document Server

    Gray, Alan

    2016-01-01

    Leading HPC systems achieve their status through use of highly parallel devices such as NVIDIA GPUs or Intel Xeon Phi many-core CPUs. The concept of performance portability across such architectures, as well as traditional CPUs, is vital for the application programmer. In this paper we describe targetDP, a lightweight abstraction layer which allows grid-based applications to target data parallel hardware in a platform agnostic manner. We demonstrate the effectiveness of our pragmatic approach by presenting performance results for a complex fluid application (with which the model was co-designed), plus a separate lattice QCD particle physics code. For each application, a single source code base is seen to achieve portable performance, as assessed within the context of the Roofline model. TargetDP can be combined with MPI to allow use on systems containing multiple nodes: we demonstrate this through provision of scaling results on traditional and GPU-accelerated large scale supercomputers.

  9. Light-Weight Injector Technology for Cryogenic Mars Ascent Engines

    Science.gov (United States)

    Trihn, Huu Phuoc; Cramer, John M.

    1998-01-01

    Preliminary mission studies for human exploration of Mars have been performed at Marshall Space Flight Center (MSFC). These studies indicate that for chemical rockets only a cryogenic propulsion system would provide high enough performance to be considered for a Mars ascent vehicle. Although the mission is possible with Earth-supplied propellants for this vehicle, utilization of in-situ propellants is highly attractive. This option would significantly reduce the overall mass of launch vehicles. Consequently, the cost of the mission would be greatly reduced because the number and size of the Earth launch vehicle(s) needed for the mission decrease. NASA/Johnson Space Center has initiated several concept studies of in-situ propellant production plants. Liquid oxygen (LOX) is the primary candidate for an in-situ oxidizer. In-situ fuel candidates include methane (CH4), ethylene (C2H4), and methanol (CH3OH). MSFC initiated a technology development program for a cryogenic propulsion system for the Mars human exploration mission in 1998. One part of this technology program is the effort described here: an evaluation of propellant injection concepts for a LOX/liquid methane Mars Ascent Engine (MAE) with an emphasis on light-weight, high efficiency, reliability, and thermal compatibility. In addition to the main objective, hot-fire tests of the subject injectors will be used to test other key technologies including light-weight combustion chamber materials and advanced ignition concepts. This state-of-the-art technology will then be applied to the development of a cryogenic propulsion system that will meet the requirements of the planned Mars sample return (MSR) mission. The current baseline propulsion system for the MSR mission uses a storable propellant combination [monomethyl hydrazine/mixed oxides of nitrogen-25. However, a mission option that incorporates in-situ propellant production and utilization for the ascent stage is being carefully considered as a subscale

  10. Lightweight High Efficiency Electric Motors for Space Applications

    Science.gov (United States)

    Robertson, Glen A.; Tyler, Tony R.; Piper, P. J.

    2011-01-01

    Lightweight high efficiency electric motors are needed across a wide range of space applications from - thrust vector actuator control for launch and flight applications to - general vehicle, base camp habitat and experiment control for various mechanisms to - robotics for various stationary and mobile space exploration missions. QM Power?s Parallel Path Magnetic Technology Motors have slowly proven themselves to be a leading motor technology in this area; winning a NASA Phase II for "Lightweight High Efficiency Electric Motors and Actuators for Low Temperature Mobility and Robotics Applications" a US Army Phase II SBIR for "Improved Robot Actuator Motors for Medical Applications", an NSF Phase II SBIR for "Novel Low-Cost Electric Motors for Variable Speed Applications" and a DOE SBIR Phase I for "High Efficiency Commercial Refrigeration Motors" Parallel Path Magnetic Technology obtains the benefits of using permanent magnets while minimizing the historical trade-offs/limitations found in conventional permanent magnet designs. The resulting devices are smaller, lower weight, lower cost and have higher efficiency than competitive permanent magnet and non-permanent magnet designs. QM Power?s motors have been extensively tested and successfully validated by multiple commercial and aerospace customers and partners as Boeing Research and Technology. Prototypes have been made between 0.1 and 10 HP. They are also in the process of scaling motors to over 100kW with their development partners. In this paper, Parallel Path Magnetic Technology Motors will be discussed; specifically addressing their higher efficiency, higher power density, lighter weight, smaller physical size, higher low end torque, wider power zone, cooler temperatures, and greater reliability with lower cost and significant environment benefit for the same peak output power compared to typically motors. A further discussion on the inherent redundancy of these motors for space applications will be provided.

  11. Simulation of the Vacuum Assisted Resin Transfer Molding (VARTM) process and the development of light-weight composite bridging

    Science.gov (United States)

    Robinson, Marc J.

    A continued desire for increased mobility in the aftermath of natural disasters, or on the battlefield, has lead to the need for improved light-weight bridging solutions. This research investigates the development of a carbon/epoxy composite bridging system to meet the needs for light-weight bridging. The research focuses on two main topics. The first topic is that of processing composite structures and the second is the design and testing of these structures. In recent years the Vacuum Assisted Resin Transfer Molding (VARTM) process has become recognized as a low-cost manufacturing alternative for large Fiber Reinforced Polymer (FRP) composite structures for civil, military, and aerospace applications. The success of the VARTM process (complete wet-out) is very sensitive to the resin injection strategy used and the proper placement of flow distribution materials and inlet and vacuum ports. Predicting the flow front pattern, the time required for infusing a part with resin, and the time required to bleed excess resin at the end of filling, is critical to ensure that the part will become completely impregnated and desired fiber volume fractions achieved prior to the resin gelling (initiation of cure). In order to eliminate costly trial and error experiments to determine the optimal infusion strategy, this research presents a simulation model which considers in-plane flow as well as flow through the thickness of the preform. In addition to resin filling, the current model is able to simulate the bleeding of resin at the end of filling to predict the required bleeding time to reach desired fiber volume fractions for the final part. In addition to processing, the second portion of the dissertation investigates the design and testing of composite bridge deck sections which also serve as short-span bridging for gaps up to 4 m in length. The research focuses on the design of a light-weight core material for bridge decking as well as proof loading of short-span bridge

  12. An introduction to finite projective planes

    CERN Document Server

    Albert, Abraham Adrian

    2015-01-01

    Geared toward both beginning and advanced undergraduate and graduate students, this self-contained treatment offers an elementary approach to finite projective planes. Following a review of the basics of projective geometry, the text examines finite planes, field planes, and coordinates in an arbitrary plane. Additional topics include central collineations and the little Desargues' property, the fundamental theorem, and examples of finite non-Desarguesian planes.Virtually no knowledge or sophistication on the part of the student is assumed, and every algebraic system that arises is defined and

  13. Conserved role of unc-79 in ethanol responses in lightweight mutant mice.

    Directory of Open Access Journals (Sweden)

    David J Speca

    2010-08-01

    Full Text Available The mechanisms by which ethanol and inhaled anesthetics influence the nervous system are poorly understood. Here we describe the positional cloning and characterization of a new mouse mutation isolated in an N-ethyl-N-nitrosourea (ENU forward mutagenesis screen for animals with enhanced locomotor activity. This allele, Lightweight (Lwt, disrupts the homolog of the Caenorhabditis elegans (C. elegans unc-79 gene. While Lwt/Lwt homozygotes are perinatal lethal, Lightweight heterozygotes are dramatically hypersensitive to acute ethanol exposure. Experiments in C. elegans demonstrate a conserved hypersensitivity to ethanol in unc-79 mutants and extend this observation to the related unc-80 mutant and nca-1;nca-2 double mutants. Lightweight heterozygotes also exhibit an altered response to the anesthetic isoflurane, reminiscent of unc-79 invertebrate mutant phenotypes. Consistent with our initial mapping results, Lightweight heterozygotes are mildly hyperactive when exposed to a novel environment and are smaller than wild-type animals. In addition, Lightweight heterozygotes exhibit increased food consumption yet have a leaner body composition. Interestingly, Lightweight heterozygotes voluntarily consume more ethanol than wild-type littermates. The acute hypersensitivity to and increased voluntary consumption of ethanol observed in Lightweight heterozygous mice in combination with the observed hypersensitivity to ethanol in C. elegans unc-79, unc-80, and nca-1;nca-2 double mutants suggests a novel conserved pathway that might influence alcohol-related behaviors in humans.

  14. Thermodynamics of black plane solution

    CERN Document Server

    Rodrigues, Manuel E; Houndjo, Stéphane J M

    2012-01-01

    We obtain a new phantom black plane solution in 4D of the Einstein-Maxwell theory coupled with a cosmological constant. We analyse their basic properties and obtain the extensive and intensive thermodynamic variables, as well as the specific heat and the first law. Through the specific heat and the so-called geometric methods, we analyse in detail their thermodynamic properties, the extreme and phase transition limits, as well as the local and global stabilities of the system. The normal case is shown with an extreme limit and the phantom one with a phase transition only for null mass. The systems present local and global stabilities for certain values of the entropy density with respect to the electric charge, for the canonical and grand canonical ensembles.

  15. Thermodynamics of black plane solution

    Science.gov (United States)

    Rodrigues, Manuel E.; Jardim, Deborah F.; Houndjo, Stéphane J. M.; Myrzakulov, Ratbay

    2013-11-01

    We obtain a new phantom black plane solution in D of the Einstein-Maxwell theory coupled with a cosmological constant. We analyse their basic properties, as well as its causal structure, and obtain the extensive and intensive thermodynamic variables, as well as the specific heat and the first law. Through the specific heat and the so-called geometric methods, we analyse in detail their thermodynamic properties, the extreme and phase transition limits, as well as the local and global stabilities of the system. The normal case is shown with an extreme limit and the phantom one with a phase transition only for null mass, which is physically inaccessible. The systems present local and global stabilities for certain values of the entropy density with respect to the electric charge, for the canonical and grand canonical ensembles.

  16. On plane submerged laminar jets

    Science.gov (United States)

    Coenen, Wilfried; Sanchez, Antonio L.

    2016-11-01

    We address the laminar flow generated when a developed stream of liquid of kinematic viscosity ν flowing along channel of width 2 h discharges into an open space bounded by two symmetric plane walls departing from the channel rim with an angle α 1 . Attention is focused on values of the jet volume flux 2 Q such that the associated Reynolds number Re = Qh / ν is of order unity. The formulation requires specification of the boundary conditions far from the channel exit. If the flow is driven by the volume flux, then the far-field solution corresponds to Jeffery-Hamel self-similar flow. However, as noted by Fraenkel (1962), such solutions exist only for α potential flow driven by the jet entrainment, and a Falkner-Skan near-wall boundary layer. Numerical integrations of the Navier-Stokes equations are used to ascertain the existence of these different solutions.

  17. Lightweight design and finite element analysis of primary mirror for the space telescope

    Science.gov (United States)

    Zhang, Dandan; Li, Weiyan; Lv, Qunbo; Liu, Yangyang; Chen, Xinwen

    2015-09-01

    In order to satisfy the strict requirements of the lightweight ratios and high dimensional stability for space mirror, the design method of lightweight structure and the flexible supporting structure of the primary mirror is proposed. Subsequently, the surface deformations of two different lightweight structures for primary mirror are discussed for analyzing the influence of the mirror weight on its surface. Finally, the finite element models for primary mirror assembly are built for calculating the surface deformation caused by different gravity orientations and various thermal environments. It is proved that the weight, stiffness and surface accuracy of the structure design for primary mirror can meet the engineering requirement.

  18. A Specialized Lightweight Metamorphic Function for KASUMI Metamorphic Cipher and Its FPGA Implementation

    Directory of Open Access Journals (Sweden)

    Rabie A. Mahmoud

    2016-08-01

    Full Text Available To enhance the performance of the KASUMI Metamorphic Cipher, we apply a lightweight Metamorphic Structure. The proposed structure uses four lightweight bit-balanced operations in the function Meta-FO of the KASUMI Metamorphic Cipher. These operations are: XOR, INV, XNOR, and NOP for bitwise XOR, invert, XNOR, and no operation respectively building blocks of the Specialized Crypto Logic Unit (SCLU. In this work, we present a lightweight KASUMI Specialized-Metamorphic Cipher. In addition, we provide a Field Programmable Gate Array (FPGA implementation of the proposed algorithm modification.

  19. Project CONDOR: Middle atmosphere wind structure obtained with lightweight inflatable spheres near the equatorial electrojet

    Science.gov (United States)

    Schmidlin, F. J.

    1987-01-01

    Observed correlations between the atmospheric electric field and the neutral wind were studied using additional atmospheric measurements during Project CONDOR. Project CONDOR obtained measurements near the equatorial electrojet (12 S) during March 1983. Neutral atmosphere wind measurements were obtained using lightweight inflatable spheres and temperatures were obtained using a datasonde. The lightweight sphere technology, the wind structure, and temperature structure are described. Results show that the lightweight sphere gives higher vertical resolution of winds below 75 km compared with the standard sphere, but gives little or no improvement above 80 km, and no usable temperature and density data.

  20. M-FILE FOR MIX DESIGN OF STRUCTURAL LIGHTWEIGHT CONCRETE USING DEVELOPED MODELS

    Directory of Open Access Journals (Sweden)

    M. ABDULLAHI

    2011-08-01

    Full Text Available An m-file for mix design of structural lightweight concrete is presented. Mix design of structural lightweight concrete is conducted using guide in the standards. This may be tasking involving reading and understanding of the relevant standards. This renders the process inefficient and liable to errors in computations. A computer approach to mix design will alleviate this problem. An m-file was developed in MATLAB environment for the concrete mix design. The m-file has been tested and has proved to be efficient in computing the mix composition for the first trial batch of lightweight concrete mixes. It can also perform concrete mixture proportioning adjustment.

  1. Solidification, growth mechanisms, and associated properties of Al-Si and magnesium lightweight casting alloys

    Energy Technology Data Exchange (ETDEWEB)

    Hosch, Timothy [Iowa State Univ., Ames, IA (United States)

    2010-01-01

    Continually rising energy prices have inspired increased interest in weight reduction in the automotive and aerospace industries, opening the door for the widespread use and development of lightweight structural materials. Chief among these materials are cast Al-Si and magnesium-based alloys. Utilization of Al-Si alloys depends on obtaining a modified fibrous microstructure in lieu of the intrinsic flake structure, a process which is incompletely understood. The local solidification conditions, mechanisms, and tensile properties associated with the flake to fiber growth mode transition in Al-Si eutectic alloys are investigated here using bridgman type gradient-zone directional solidification. Resulting microstructures are examined through quantitative image analysis of two-dimensional sections and observation of deep-etched sections showing three-dimensional microstructural features. The transition was found to occur in two stages: an initial stage dominated by in-plane plate breakup and rod formation within the plane of the plate, and a second stage where the onset of out-of-plane silicon rod growth leads to the formation of an irregular fibrous structure. Several microstructural parameters were investigated in an attempt to quantify this transition, and it was found that the particle aspect ratio is effective in objectively identifying the onset and completion velocity of the flake to fiber transition. The appearance of intricate out-of-plane silicon instability formations was investigated by adapting a perturbed-interface stability analysis to the Al-Si system. Measurements of silicon equilibrium shape particles provided an estimate of the anisotropy of the solid Si/liquid Al-Si system and incorporation of this silicon anisotropy into the model was found to improve prediction of the instability length scale. Magnesium alloys share many of the benefits of Al-Si alloys, with the added benefit of a 1/3 lower density and increased machinability. Magnesium castings

  2. Solidification, growth mechanisms, and associated properties of aluminum-silicon and magnesium lightweight casting alloys

    Science.gov (United States)

    Hosch, Timothy Al

    Continually rising energy prices have inspired increased interest in weight reduction in the automotive and aerospace industries, opening the door for the widespread use and development of lightweight structural materials. Chief among these materials are cast Al-Si and magnesium-based alloys. Utilization of Al-Si alloys depends on obtaining a modified fibrous microstructure in lieu of the intrinsic flake structure, a process which is incompletely understood. The local solidification conditions, mechanisms, and tensile properties associated with the flake to fiber growth mode transition in Al-Si eutectic alloys are investigated here using bridgman type gradient-zone directional solidification. Resulting microstructures are examined through quantitative image analysis of two-dimensional sections and observation of deep-etched sections showing three-dimensional microstructural features. The transition was found to occur in two stages: an initial stage dominated by in-plane plate breakup and rod formation within the plane of the plate, and a second stage where the onset of out-of-plane silicon rod growth leads to the formation of an irregular fibrous structure. Several microstructural parameters were investigated in an attempt to quantify this transition, and it was found that the particle aspect ratio is effective in objectively identifying the onset and completion velocity of the flake to fiber transition. The appearance of intricate out-of-plane silicon instability formations was investigated by adapting a perturbed-interface stability analysis to the Al-Si system. Measurements of silicon equilibrium shape particles provided an estimate of the anisotropy of the solid Si/liquid Al-Si system and incorporation of this silicon anisotropy into the model was found to improve prediction of the instability length scale. Magnesium alloys share many of the benefits of Al-Si alloys, with the added benefit of a 1/3 lower density and increased machinability. Magnesium castings

  3. Generalized plane gravitational waves of non-symmetric unified field theories in plane symmetry

    Directory of Open Access Journals (Sweden)

    Sanjiv R. Bhoyar

    2012-12-01

    Full Text Available In this paper we investigated the plane wave solutions of both the weak and strong non-symmetric unified field equations of Einstein and Bonner in a generalized plane symmetric space-time in the sense of Taub [Ann. Math. 53, 472 (1951] for plane gravitational waves. We show that the plane wave solutions of Einstein and Bonner field equations exist in plane symmetry.

  4. Novel Architecture for a Long-Life, Lightweight Venus Lander

    Science.gov (United States)

    Bugby, D.; Seghi, S.; Kroliczek, E.; Pauken, M.

    2009-03-01

    This paper describes a novel concept for an extended lifetime, lightweight Venus lander. Historically, to operate in the 480° C, 90 atm, corrosive, mostly CO2 Venus surface environment, previous landers have relied on thick Ti spherical outer shells and thick layers of internal insulation. But even the most resilient of these landers operated for only about 2 hours before succumbing to the environment. The goal on this project is to develop an architecture that extends lander lifetime to 20-25 hours and also reduces mass compared to the Pioneer Venus mission architecture. The idea for reducing mass is to: (a) contain the science instruments within a spherical high strength lightweight polymer matrix composite (PMC) tank; (b) surround the PMC tank with an annular shell of high performance insulation pre-pressurized to a level that (after landing) will exceed the external Venus surface pressure; and (c) surround the insulation with a thin Ti outer shell that contains only a net internal pressure, eliminating buckling overdesign mass. The combination of the PMC inner tank and thin Ti outer shell is lighter than a single thick Ti outer shell. The idea for extending lifetime is to add the following three features: (i) an expendable water supply that is placed within the insulation or is contained in an additional vessel within the PMC tank; (ii) a thin spherical evaporator shell placed within the insulation a short radial distance from the outer shell; and (iii) a thin heat-intercepting liquid cooled shield placed inboard of the evaporator shell. These features lower the temperature of the insulation below what it would have been with the insulation alone, reducing the internal heat leak and lengthening lifetime. The use of phase change materials (PCMs) inside the PMC tank is also analyzed as a lifetime-extending design option. The paper describes: (1) analytical modeling to demonstrate reduced mass and extended life; (2) thermal conductivity testing of high

  5. Focal Plane Instrumentation of VERITAS

    CERN Document Server

    Nagai, T; Sleege, G; Petry, D

    2007-01-01

    VERITAS is a new atmospheric Cherenkov imaging telescope array to detect very high energy gamma rays above 100 GeV. The array is located in southern Arizona, USA, at an altitude of 1268m above sea level. The array consists of four 12-m telescopes of Davies-Cotton design and structurally resembling the Whipple 10-m telescope. The four focal plane instruments are equipped with high-resolution (499 pixels) fast photo-multiplier-tube (PMT) cameras covering a 3.5 degree field of view with 0.15 degree pixel separation. Light concentrators reduce the dead-space between PMTs to 25% and shield the PMTs from ambient light. The PMTs are connected to high-speed preamplifiers allowing operation at modest anode current and giving good single photoelectron peaks in situ. Electronics in the focus box provides real-time monitoring of the anode currents for each pixel and ambient environmental conditions. A charge injection subsystem installed in the focus box allows daytime testing of the trigger and data acquisition system b...

  6. Radioactivity in the galactic plane

    Science.gov (United States)

    Walraven, G. D.; Haymes, R. C.

    1976-01-01

    The paper reports the detection of a large concentration of interstellar radioactivity during balloon-altitude measurements of gamma-ray energy spectra in the band between 0.02 and 12.27 MeV from galactic and extragalactic sources. Enhanced counting rates were observed in three directions towards the plane of the Galaxy; a power-law energy spectrum is computed for one of these directions (designated B 10). A large statistical deviation from the power law in a 1.0-FWHM interval centered near 1.16 MeV is discussed, and the existence of a nuclear gamma-ray line at 1.15 MeV in B 10 is postulated. It is suggested that Ca-44, which emits gamma radiation at 1.156 MeV following the decay of radioactive Sc-44, is a likely candidate for this line, noting that Sc-44 arises from Ti-44 according to explosive models of supernova nucleosynthesis. The 1.16-MeV line flux inferred from the present data is shown to equal the predicted flux for a supernova at a distance of approximately 3 kpc and an age not exceeding about 100 years.

  7. A Collaborative Knowledge Plane for Autonomic Networks

    Science.gov (United States)

    Mbaye, Maïssa; Krief, Francine

    Autonomic networking aims to give network components self-managing capabilities. Several autonomic architectures have been proposed. Each of these architectures includes sort of a knowledge plane which is very important to mimic an autonomic behavior. Knowledge plane has a central role for self-functions by providing suitable knowledge to equipment and needs to learn new strategies for more accuracy.However, defining knowledge plane's architecture is still a challenge for researchers. Specially, defining the way cognitive supports interact each other in knowledge plane and implementing them. Decision making process depends on these interactions between reasoning and learning parts of knowledge plane. In this paper we propose a knowledge plane's architecture based on machine learning (inductive logic programming) paradigm and situated view to deal with distributed environment. This architecture is focused on two self-functions that include all other self-functions: self-adaptation and self-organization. Study cases are given and implemented.

  8. Lightweight Ultrahigh Temperature CMC-Lined C/C Combustion Chambers, Phase II Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA and DoD are seeking high-performance, lightweight liquid rocket combustion chambers with future performance goals that cannot be achieved using state-of-the-art...

  9. Self Deployable Ultra-Lightweight Modular Unit for Habitat Structural Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Space deployable and rigidizable structures which are ultra-lightweight, and have high rigidity, space durability, and high impact resistance are desirable to...

  10. Ultra-Lightweight, High Efficiency Silicon-Carbide (SIC) Based Power Electronic Converters Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This Small Business of Innovation Research Phase I proposal seeks to investigate and prove the feasibility of developing highly efficient, ultra-lightweight SiC...

  11. Ultra-Lightweight High Efficiency Nanostructured Materials and Coatings for Deep Space Mission Environments Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NanoSonic has developed a nanostructured spray self-assembly manufacturing method that has resulted in ultra-lightweight (< 0.4g/cc) textile interconnects for...

  12. Lightweight and Compace Multifunction Computer-Controlled Strength and Aerobic Training Device Project

    Data.gov (United States)

    National Aeronautics and Space Administration — TDA Research proposes to develop a computer-controlled lightweight and compact device for aerobic and resistive training (DART) to counteract muscular atrophy and...

  13. Flexible, Lightweight, Low-Cost Organic Photovoltaics with Improved Efficiency Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Both manned and unmanned off-Earth missions of the future will require very lightweight, high efficiency, flexible and durable photovoltaic (PV) arrays to generate...

  14. Ultra-Lightweight Nanocomposite Foams and Sandwich Structures for Space Structures Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Space structures that are ultra-lightweight, and have gas barrier property, space durability, radiation resistance, EMI shielding, and high impact resistance are...

  15. CIRS-lite as a lightweight atmospheric sounder for Earth trace-gas science Project

    Data.gov (United States)

    National Aeronautics and Space Administration — CIRS-lite is a lightweight  version of the CIRS 43-kg Fourier transform spectrometer (FTS) currently returning data from Saturn.  CIRS-lite is of interest...

  16. Lightweight Brick by Carbon Ash from The Mixed Plastic Waste Treatment Plant

    Directory of Open Access Journals (Sweden)

    Chen Kuo-Wei

    2016-01-01

    Full Text Available This study was designed to investigate the mixed plastic waste from the production of light carbon ash bricks performance. The mixed waste plastic pyrolysis process generated waste - Carbon ash. After extrusion, a Lightweight brick was made by carbon ash, additive and Cement mortar. In general, the set compressive strength and insulation effect of lightweight bricks with carbon ash proportion for significant impact. The set water absorption and thermal conductivity of lightweight bricks with carbon ash proportion for significant impact. The set density of lightweight brick ameliorates with M3824 additive and CM3 cement mortar for significant impact. Under conditions of technology and economic, the results of this study as reference for market-oriented marketing and commercialization of production.

  17. Ultra-Lightweight Self-Deployable SMP Nanocomposite Sandwich for Habitat Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Space deployable and rigidizable structures that are ultra-lightweight, and have gas barrier property, space durability, and high impact resistance are desirable to...

  18. A Compact, Light-weight, Reliable and Highly Efficient Heat Pump for Project

    Data.gov (United States)

    National Aeronautics and Space Administration — RTI proposes to develop an efficient, reliable, compact and lightweight heat pump for space applications. The proposed effort is expected to lead to (at the end of...

  19. Silicon Carbide Lightweight Optics With Hybrid Skins for Large Cryo Telescopes Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Optical Physics Company (OPC) proposes to manufacture new silicon carbide (SiC) foam-based optics that are composite, athermal and lightweight (FOCAL) that provide...

  20. Ultra-Lightweight Nanocomposite Foams and Sandwich Structures for Space Structures Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Space structures that are ultra-lightweight, and have gas barrier property, space durability, radiation resistance and high impact resistance are desirable to...

  1. Actively Cooled Silicon Lightweight Mirrors for Far Infrared and Submillimeter Optical Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The NASA Space Science Enterprise has 2 themes requiring large, lightweight cryogenic mirrors: Astronomical Search for Origins and Planetary Systems (ASO) and the...

  2. Lightweight Design of an HTS Coil for the VASIMR Experiment Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this Phase II SBIR contract Tai-Yang Research Company of Tennessee proposes to design, fabricate, and test an ultra-lightweight High Temperature Superconducting...

  3. Actively Cooled Silicon Lightweight Mirrors for Far Infrared and Submillimeter Optical Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Schafer proposes to demonstrate 2 different methods for actively cooling our 5-7.5 kg/m2 areal density Silicon Lightweight Mirrors (SLMS?) technology for future NASA...

  4. Innovative, Lightweight Thoraeus RubberTM for MMOD and Space Radiation Shielding Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NanoSonic offers an innovative manufacturing process to yield ultra-lightweight radiation shielding nanocomposites by exploiting the concept of the Thoraeus filter...

  5. Lightweight Hybrid Ablator Incorporating Aerogel-Filled Open-Cell Foam Structural Insulator, Phase II Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In previous work for NASA and DoD, Ultramet developed lightweight open-cell foam insulators composed of a carbon or ceramic structural foam skeleton filled with a...

  6. Lightweight Hybrid Ablator Incorporating Aerogel-Filled Open-Cell Foam Structural Insulator Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In previous work for NASA and DoD, Ultramet developed lightweight open-cell foam insulators composed of a carbon or ceramic structural foam skeleton filled with a...

  7. Efficient Lightweight AC-AC Power Control for Solar UAV Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A highly efficient and lightweight dual bridge matrix power controller development is proposed that will provide high performance to a solar powered high altitude...

  8. Scalable, Lightweight, Low-Cost Aero/Electrodynamic Drag Deorbit Module Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed effort will develop the "Terminator Tape Deorbit Module", a lightweight, low-cost, scalable de-orbit module that will utilize both aerodynamic drag...

  9. Lightweight Ultrahigh Temperature CMC-Encased C/C Structure for Reentry and Hypersonic Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The reentry spacecraft and hypersonic cruisers of the future will require advanced lightweight thermal protection systems that can provide the dual functionality of...

  10. Next Generation , Lightweight, Durable Boot Materials to Provide Active & Passive Thermal Protection Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this NASA Phase I SBIR program is to leverage lightweight, durable materials developed by NanoSonic for use within extra vehicular activity (EVA)...

  11. Silicon Carbide Lightweight Optics With Hybrid Skins for Large Cryo Telescopes Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Optical Physics Company (OPC) has developed new silicon carbide (SiC) foam-based optics with hybrid skins that are composite, athermal and lightweight (FOCAL) that...

  12. Mitigation of Flanking Noise Transmission in Periodic Structures of Lightweight Elements

    DEFF Research Database (Denmark)

    Domadiya, Parthkumar Gandalal

    Lightweight structures becoming increasingly popular within the building industry and hence they requires immediate attention to address their vibro-acoustic behaviour. Flanking noise transmission is one of the main concerns while using lightweight panels in buildings, since sound can travel...... characteristics in periodic structures, the structure must be simplified; hence, one dimensional structures such as bars and beams are considered for further investigation. A periodic bar model comprised of systemically placed Plexiglas and steel elements is generated using two methods: an FE method and a Floquet...... transmission in periodic structures of lightweight elements by employing various numerical, analytical and experimental methods. At first, three dimensional finite-element (FE) models of a Z-shaped lightweight panel structure based on various frame designs, inclusion of air and structural coupling between...

  13. Ultra-Lightweight, High Efficiency Silicon-Carbide (SIC) Based Power Electronic Converters Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In Phase I of this project, APEI, Inc. proved the feasibility of creating ultra-lightweight power converters (utilizing now emerging silicon carbide [SiC] power...

  14. Flexible, Lightweight, Low-Cost Organic Photovoltaics with Improved Efficiency Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Both manned and unmanned off-Earth missions of the future will require very lightweight, inexpensive, high efficiency, flexible and single-use photovoltaic (PV)...

  15. Influence of Mineral Admixtures on the Permeability of Lightweight Aggregate Concrete

    Institute of Scientific and Technical Information of China (English)

    WANG Fazhou; HU Shuguang; DING Qingjun; PENG yanzhou

    2005-01-01

    The permeability of lightweight aggregate concrete was studied. Some efforts were taken to increase the resistance of lightweight aggregate concrete (LC) to water penetration by using the mineral admixtures of fly ash, granulated blast furnace slag or silica fume. Accelerated chloride penetrability test and liquid atmosphere press method were used to study the anti-permeability of lightweight aggregate concrete. The experimental results show that fly ash, granulated blast furnace slag and silica fume can decrease the permeability of lightweight aggregate concrete, but the effect of granulated blast furnace slag is poor. According to the SEM and pore structure analyzing results,an interface self-reinforcing effect model was presented and the reinforced mechanism of mineral mixture on LC was discussed according to the model described by authors.

  16. Lightweight Metal Rubber Wire and Cable for Space Power Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this NASA STTR program is to produce ultra-lightweight electrical wire and cable harnesses to reduce the liftoff weight of future space flight...

  17. Precision Membrane Optical Shell (PMOS) Technology for Lightweight LIDAR Apertures Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Precision membrane optical shell (PMOS) technology is an innovative combination of 1) ultra lightweight optically smooth membrane thin films, 2) advanced mold based...

  18. RF/Optical Demonstration: Focal Plane Assembly

    Science.gov (United States)

    Hoppe, D. J.; Chung, S.; Kovalik, J.; Gama, E.; Fernandez, M. M.

    2016-11-01

    In this article, we describe the second-generation focal plane optical assembly employed in the RF/optical demonstration at DSS-13. This assembly receives reflected light from the two mirror segments mounted on the RF primary. The focal plane assembly contains a fast steering mirror (FSM) to stabilize the focal plane spot, a pupil camera to aid in aligning the two segments, and several additional cameras for receiving the optical signal prior to as well as after the FSM loop.

  19. FEM Simulation of Bending Formability for Laminate Steel/Resin/Steel Lightweight Composite Sheet

    Institute of Scientific and Technical Information of China (English)

    Guancheng Ll; Yonglin KANG

    2003-01-01

    The ANSYS simulation software was used to analyze the bending formability of laminate steel/resin/steel lightweight composite sheet. The skin steel at external side produces relative slipping-off change during the bending due to its composite structure. The internal stress strain states, materials effect tools parameters and intermediate layer resin of lightweight sheet on slipping-off change were analyzed. The spring back and shear stress state after bending have also been discussed.

  20. THE MECHANICAL PROPERTIES OF SELF COMPACTING LIGHTWEIGHT MORTAR WITH PUMICE AND EXPANDED PERLITE AGGREGATE

    OpenAIRE

    GONEN, Tahir

    2009-01-01

    Self compacting mortars have been used as repair mortar or to determine component rates of the self compacting concrete. In this study; self compacting lightweight mortars were produced with basaltic pumice and expanded perlite aggregate. Expanded perlite aggregate was used at rates 10, 20, 30, 40 and 50% by volume instead of pumice aggregate and compared with reference specimens made fully pumice aggregate. Self compacting lightweight mortars were compared with self compacting mortar with ri...

  1. Cost and Operational Effectiveness Analysis (COEA) for the Lightweight Water Purifier (LWP).

    Science.gov (United States)

    2007-11-02

    requirement for a Lightweight Water Purifier (LWP). Data and information from this COEA is intended to support a Milestone Decision Review ( MDR I/I1) planned... MDR ) with suitable information and analysis to enable them to: (1) Select from among the designated Lightweight Water Purifier (LWP) alternatives and...Service field water quality standards contained in Technical Bulletin, Medical ( TB MED 577). The LWP falls within the Combat Service Support (CSS

  2. Inverted Organic Photovoltaic Cells on Lightweight, and Flexible Metal Foil Substrates

    Science.gov (United States)

    2011-03-30

    Photovoltaic Cells on Lightweight, and Flexible Metal Foil Substrates Stephen R. Forrest Departments of EECS, Physics and Materials Science & Engineering...substrate are of interest because they can be deposited onto opaque, light-weight and possibly flexible materials allowing for use in cost-efficient...cathode, while the phthalocyanine donor absorbs longer wavelengths, and hence should optimally be adjacent to the transparent anode. Note that

  3. Best practices for making high integrity lightweight metal castings- molten metal composition and cleanliness control

    Institute of Scientific and Technical Information of China (English)

    Qigui Wang

    2014-01-01

    To make high integrity lightweight metal castings, best practices are required in various stages of casting and heat treatment processes, including liquid metal composition and quality control, casting and gating/riser system design, and process optimization. This paper presents best practices for liquid metal processing and quality assurance of molten metal in both melting and mold ifling. Best practices for other aspects of lightweight metal casting wil be published separately.

  4. PROPERTIES OF LIGHTWEIGHT MASONRY MORTARS WITH HOLLOW GLASS MICROSPHERES FOR WINTER CONDITIONS

    OpenAIRE

    Semenov Vyacheslav Sergeevich; Oreshkin Dmitriy Vladimirovich; Rozovskaya Tamara Alekseevna

    2012-01-01

    The authors provide their research findings concerning lightweight masonry mortars with hollow glass microspheres and antifreeze admixtures. These mortars are used in the construction of filler structures at negative temperatures. The application of multilayer filler structures causes reduction of their thermal homogeneity factor. Therefore, single-layer filler structures have the strongest potential. There is a need to employ lightweight masonry mortars to ensure the thermal homogeneity of s...

  5. Large Format Uncooled Focal Plane Array Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Black Forest Engineering has identified innovative modifications in uncooled focal plane array (UFPA) architecture and processing that allows development of large...

  6. Effects of Palm Fiber on the Mechanical Properties of Lightweight Concrete Crushed Brick

    Directory of Open Access Journals (Sweden)

    Mahyuddin Ramli

    2010-01-01

    Full Text Available Problem statement: Researches has been conducted worldwide on a large number of natural or artificial lightweight aggregates. In spite of many of the researches of using natural fibers show considerable promise, the use of natural fibers to improve the properties of lightweight concrete still required to be a subject of further research and investigation. Approach: This experimental investigation was carried out to study the properties of lightweight crushed brick concrete containing palm fiber of different volume fractions. An experimental programme was planned in which the tests such as density, compressive strength and flexural strength were conducted to investigate the properties of lightweight crushed brick concrete reinforced by palm fiber. The specimen incorporated different volume fractions of palm fiber, i.e., 0, 0.2, 0.4, 0.6, 0.8 and 1.0%. Results: Tests results showed that the use of this fiber slightly increases the density of lightweight concrete. The use of 0.8% of palm fiber increases the compressive strength and flexural strength by about 13.4 and 16.1% respectively. Conclusion: The results indicated that the use of palm fiber with lightweight crushed brick concrete enhances the mechanical properties of the concrete and the optimization of the palm fiber fractions is required to get the best performance.

  7. Towards a Certified Lightweight Array Bound Checker for Java Bytecode

    Science.gov (United States)

    Pichardie, David

    2009-01-01

    Dynamic array bound checks are crucial elements for the security of a Java Virtual Machines. These dynamic checks are however expensive and several static analysis techniques have been proposed to eliminate explicit bounds checks. Such analyses require advanced numerical and symbolic manipulations that 1) penalize bytecode loading or dynamic compilation, 2) complexify the trusted computing base. Following the Foundational Proof Carrying Code methodology, our goal is to provide a lightweight bytecode verifier for eliminating array bound checks that is both efficient and trustable. In this work, we define a generic relational program analysis for an imperative, stackoriented byte code language with procedures, arrays and global variables and instantiate it with a relational abstract domain as polyhedra. The analysis has automatic inference of loop invariants and method pre-/post-conditions, and efficient checking of analysis results by a simple checker. Invariants, which can be large, can be specialized for proving a safety policy using an automatic pruning technique which reduces their size. The result of the analysis can be checked efficiently by annotating the program with parts of the invariant together with certificates of polyhedral inclusions. The resulting checker is sufficiently simple to be entirely certified within the Coq proof assistant for a simple fragment of the Java bytecode language. During the talk, we will also report on our ongoing effort to scale this approach for the full sequential JVM.

  8. Titanium cholla : lightweight, high-strength structures for aerospace applications.

    Energy Technology Data Exchange (ETDEWEB)

    Atwood, Clinton J.; Voth, Thomas Eugene; Taggart, David G. (University of Rhode Island, Kingston, RI); Gill, David Dennis; Robbins, Joshua H.; Dewhurst, Peter (University of Rhode Island, Kingston, RI)

    2007-10-01

    Aerospace designers seek lightweight, high-strength structures to lower launch weight while creating structures that are capable of withstanding launch loadings. Most 'light-weighting' is done through an expensive, time-consuming, iterative method requiring experience and a repeated design/test/redesign sequence until an adequate solution is obtained. Little successful work has been done in the application of generalized 3D optimization due to the difficulty of analytical solutions, the large computational requirements of computerized solutions, and the inability to manufacture many optimized structures with conventional machining processes. The Titanium Cholla LDRD team set out to create generalized 3D optimization routines, a set of analytically optimized 3D structures for testing the solutions, and a method of manufacturing these complex optimized structures. The team developed two new computer optimization solutions: Advanced Topological Optimization (ATO) and FlexFEM, an optimization package utilizing the eXtended Finite Element Method (XFEM) software for stress analysis. The team also developed several new analytically defined classes of optimized structures. Finally, the team developed a 3D capability for the Laser Engineered Net Shaping{trademark} (LENS{reg_sign}) additive manufacturing process including process planning for 3D optimized structures. This report gives individual examples as well as one generalized example showing the optimized solutions and an optimized metal part.

  9. Lightweight diesel engine designs for commuter type aircraft

    Science.gov (United States)

    Brouwers, A. P.

    1981-01-01

    Conceptual designs and performance of advanced technology lightweight diesel engines, suitable for commuter type aircraft power plants are defined. Two engines are discussed, a 1491 kW (2000 SHP) eight-cylinder engine and a 895 kW (1200 SHP) six-cylinder engine. High performance and related advanced technologies are proposed such as insulated cylinders, very high injection pressures and high compressor and turbine efficiencies. The description of each engine includes concept drawings, a performance analysis, and weight data. Fuel flow data are given for full and partial power up to 7620m altitude. The performance data are also extrapolated over a power range from 671 kW(900SHP) to 1864 kW (2500 SHP). The specific fuel consumption of the 1491 kW (2000 SHP) engine is 182 g/hWh (.299 lb/HPh) at cruise altitude, its weight 620 kg (1365 lb.) and specific weight .415 kg/kW (.683 lb/HP). The specific fuel consumption of the 895 kW (1200 SHP) engine is 187 g/hWh (.308 lb/HPh) at cruise altitude, its weight 465 kg (1025 lb.) and specific weight .520 kg/kW (.854 lb/HP).

  10. Lightweight distributed computing for intraoperative real-time image guidance

    Science.gov (United States)

    Suwelack, Stefan; Katic, Darko; Wagner, Simon; Spengler, Patrick; Bodenstedt, Sebastian; Röhl, Sebastian; Dillmann, Rüdiger; Speidel, Stefanie

    2012-02-01

    In order to provide real-time intraoperative guidance, computer assisted surgery (CAS) systems often rely on computationally expensive algorithms. The real-time constraint is especially challenging if several components such as intraoperative image processing, soft tissue registration or context aware visualization are combined in a single system. In this paper, we present a lightweight approach to distribute the workload over several workstations based on the OpenIGTLink protocol. We use XML-based message passing for remote procedure calls and native types for transferring data such as images, meshes or point coordinates. Two different, but typical scenarios are considered in order to evaluate the performance of the new system. First, we analyze a real-time soft tissue registration algorithm based on a finite element (FE) model. Here, we use the proposed approach to distribute the computational workload between a primary workstation that handles sensor data processing and visualization and a dedicated workstation that runs the real-time FE algorithm. We show that the additional overhead that is introduced by the technique is small compared to the total execution time. Furthermore, the approach is used to speed up a context aware augmented reality based navigation system for dental implant surgery. In this scenario, the additional delay for running the computationally expensive reasoning server on a separate workstation is less than a millisecond. The results show that the presented approach is a promising strategy to speed up real-time CAS systems.

  11. Lightweight Proofs of Retrievability for Electronic Evidence in Cloud

    Directory of Open Access Journals (Sweden)

    Hongyao Deng

    2013-07-01

    Full Text Available Proofs of Retrievability (PoR is one of the basic functions of electronic evidence preservation center in cloud. This paper proposes two PoR schemes to execute the workflow of evidence preservation center, which are named Finer Grained Proofs of Retrievability (FG-PoR and More Lightweight Proofs of Retrievability (ML-PoR. The two PoR schemes do not use multi-replication technology or erasure code technology, but employ the verification tags and signatures to implement provable data possession and data recovery dual functions. When some data blocks have been lost in Archive Storage Area (ASA, FG-PoR can recover each data block of evidence matrix, but ML-PoR can only recover a column of evidence matrix. The analysis results show our two PoR schemes do not only provide the integrity verification guarantee but also have robust recovery guarantee to electronic evidence in cloud. The two schemes can allow for lower computation and storage costs than other similar schemes; moreover, ML-PoR can provide lower costs than FG-PoR.

  12. Mechanical, Thermal and Functional Properties of Green Lightweight Foamcrete

    Directory of Open Access Journals (Sweden)

    Md Azree Othuman Mydin

    2012-09-01

    Full Text Available In recent times, the construction industry has revealed noteworthy attention in the use of lightweight foamcrete as a building material due to its many favourable characteristics such as lighter weight, easy to fabricate, durable and cost effective. Foamcrete is a material consisting of Portland cement paste or cement filler matrix (mortar with a homogeneous pore structure created by introducing air in the form of small bubbles. With a proper control in dosage of foam and methods of production, a wide range of densities (400 – 1600 kg/m 3 of foamcrete can be produced thus providing flexibility for application such as structural elements, partition, insulating materials and filling grades. Foamcrete has so far been applied primarily as a filler material in civil engineering works. However, its good thermal and acoustic performance indicates its strong potential as a material in building construction. The focus of this paper is to classify literature on foamcrete in terms of its mechanical, thermal and functional properties.

  13. Lightweight Solar Vehicle Impact Analysis Using ABAQUS/EXPLICIT

    Directory of Open Access Journals (Sweden)

    Rossi Passarella

    2012-12-01

    Full Text Available This paper described the Abaqus/Explicit 6.7 simulation work performed to study the frontal crash impact condition for an in-house designed and produced lightweight solar vehicle main structural body. The structural body was fabricated from aluminum hollow pipes welded together. The analysis is needed to safeguard the safety of the vehicle driver. The dynamic response of the vehicle structure when subjected to frontal impact condition was simulated, according to NASA best practice for crash test methodology. The simulated speed used was based on the NHTSA standard. Comparison of the analysis with the standard Head Injury Criteria (HIC and Chest Injury Criteria (CIC revealed that the driver of the designed vehicle would not be risk because the acceleration resultant was found to be lower than 20 G.  The analysis also proved that structural component was able to protect the driver during any frontal collision incident. However, to ensure the safety of the driver, safety precautions such as the use of seatbelt and helmet as well as driving below the speed limit are recommended.

  14. Study of water infiltration in a lightweight green roof substrate

    Science.gov (United States)

    Tomankova, Klara; Holeckova, Martina; Jelinkova, Vladimira; Snehota, Michal

    2015-04-01

    Green roofs have a positive impact on the environment (e.g. improving microclimate and air quality in cities, reducing solar absorbance and storm water). A laboratory infiltration experiment was conducted on the narrow flume serving as 2D vertical model of a green roof. The lightweight Optigreen substrate Type M was used (depth of 20 cm). The front wall of the flume was transparent and inspected by digital camera. The experiment was designed to measure pressure head, volumetric water content and calculate water retention in the substrate. Experiment comprised three artificial rainfall intensities with different values of initial water content of the substrate. The experimental results confirmed that green roofs have the ability to retain rainwater and thus have a beneficial effect on reducing runoff. In the experiment with the artificial 10 minutes rainfall event (total precipitation of 29 mm), the air dry substrate retained 95.9 % of precipitation. On the other hand for moist initial condition 4.2 % of precipitations amount was captured in the substrate. Additionally, the analysis of images taken during the experiment confirmed preferential flow and uneven advancement of the wetting front. The research was realized as a part of the University Centre for Energy Efficient Buildings supported by the EU and with financial support from the Czech Science Foundation under project number 14-10455P.

  15. Lightweight mid-infrared methane sensor for unmanned aerial systems

    Science.gov (United States)

    Golston, Levi M.; Tao, Lei; Brosy, Caroline; Schäfer, Klaus; Wolf, Benjamin; McSpiritt, James; Buchholz, Bernhard; Caulton, Dana R.; Pan, Da; Zondlo, Mark A.; Yoel, David; Kunstmann, Harald; McGregor, Marty

    2017-06-01

    The design and field performance of a compact diode laser-based instrument for measuring methane on unmanned aerial systems (UAS) is described. The system is based on open-path, wavelength modulation spectroscopy with a 3.27 µm GaSb laser. We design two versions of the sensor for a long-endurance fixed wing UAS and a rotary wing hexacopter, with instrument masses of 4.6 and 1.6 kg, respectively. The long-endurance platform was used to measure vertical profiles of methane up to 600 m in altitude and showed repeatability of 13 ppbv between multiple profiles. Additionally, the hexacopter system was used to evaluate the evolution of methane in the nocturnal boundary layer during the ScaleX field campaign in Germany, where measured data is consistent with supporting ground-based methane and meteorological measurements. Testing results on both platforms demonstrated our lightweight methane sensor had an in-flight precision of 5-10 ppbv Hz-1/2.

  16. SIT: A Lightweight Encryption Algorithm for Secure Internet of Things

    Directory of Open Access Journals (Sweden)

    Muhammad Usman

    2017-01-01

    Full Text Available The Internet of Things (IoT being a promising technology of the future is expected to connect billions of devices. The increased number of communication is expected to generate mountains of data and the security of data can be a threat. The devices in the architecture are essentially smaller in size and low powered. Conventional encryption algorithms are generally computationally expensive due to their complexity and requires many rounds to encrypt, essentially wasting the constrained energy of the gadgets. Less complex algorithm, however, may compromise the desired integrity. In this paper we propose a lightweight encryption algorithm named as Secure IoT (SIT. It is a 64-bit block cipher and requires 64-bit key to encrypt the data. The architecture of the algorithm is a mixture of feistel and a uniform substitution-permutation network. Simulations result shows the algorithm provides substantial security in just five encryption rounds. The hardware implementation of the algorithm is done on a low cost 8-bit micro-controller and the results of code size, memory utilization and encryption/decryption execution cycles are compared with benchmark encryption algo-rithms. The MATLAB code for relevant simulations is available online at https://goo.gl/Uw7E0W.

  17. Lightweight alumina refractory aggregate: Phase 3, Full-scale demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Swansiger, T.G.; Pearson, A.

    1996-07-16

    Technical problems (higher than target fired density, and poor intermediate strength after burnout but before sintering) were addressed and solved; solution involved use of large loading of CP-5 alumina (controlled pore, rehydratable), increased loading of one of the binders, and a steam aging step. Resistance of the lightweight aggregate in a brick formulation to steel slag penetration was assessed in a preliminary test and found to be almost as good as that of T-64. Pelletized process economic feasibility study was updated, based on production levels of 10,000 and 20,000 mt/year, the most up- to-date raw material costs, and the assumption of a retrofit into the Arkansas plant tabular production facility. For the 10,000 mt/y production level, the required selling price of 35% more than the T- 64 selling price exceeds the {le}25% objective. The market survey will determine whether to proceed with the full scale demonstration that will produce at least 54.4 mt (120,000 lb) of the aggregate for incorporation into products, followed by end-user testing and evaluation.

  18. Toward lightweight biometric signal processing for wearable devices.

    Science.gov (United States)

    Francescon, Roberto; Hooshmand, Mohsen; Gadaleta, Matteo; Grisan, Enrico; Yoon, Seung Keun; Rossi, Michele

    2015-01-01

    Wearable devices are becoming a natural and economic means to gather biometric data from end users. The massive amount of information that they will provide, unimaginable until a few years ago, owns an immense potential for applications such as continuous monitoring for personalized healthcare and use within fitness applications. Wearables are however heavily constrained in terms of amount of memory, transmission capability and energy reserve. This calls for dedicated, lightweight but still effective algorithms for data management. This paper is centered around lossy data compression techniques, whose aim is to minimize the amount of information that is to be stored on their onboard memory and subsequently transmitted over wireless interfaces. Specifically, we analyze selected compression techniques for biometric signals, quantifying their complexity (energy consumption) and compression performance. Hence, we propose a new class of codebook-based (CB) compression algorithms, designed to be energy efficient, online and amenable to any type of signal exhibiting recurrent patterns. Finally, the performance of the selected and the new algorithm is assessed, underlining the advantages offered by CB schemes in terms of memory savings and classification algorithms.

  19. Abstracting massive data for lightweight intrusion detection in computer networks

    KAUST Repository

    Wang, Wei

    2016-10-15

    Anomaly intrusion detection in big data environments calls for lightweight models that are able to achieve real-time performance during detection. Abstracting audit data provides a solution to improve the efficiency of data processing in intrusion detection. Data abstraction refers to abstract or extract the most relevant information from the massive dataset. In this work, we propose three strategies of data abstraction, namely, exemplar extraction, attribute selection and attribute abstraction. We first propose an effective method called exemplar extraction to extract representative subsets from the original massive data prior to building the detection models. Two clustering algorithms, Affinity Propagation (AP) and traditional . k-means, are employed to find the exemplars from the audit data. . k-Nearest Neighbor (k-NN), Principal Component Analysis (PCA) and one-class Support Vector Machine (SVM) are used for the detection. We then employ another two strategies, attribute selection and attribute extraction, to abstract audit data for anomaly intrusion detection. Two http streams collected from a real computing environment as well as the KDD\\'99 benchmark data set are used to validate these three strategies of data abstraction. The comprehensive experimental results show that while all the three strategies improve the detection efficiency, the AP-based exemplar extraction achieves the best performance of data abstraction.

  20. Evaluation method of cracking resistance of lightweight aggregate concrete

    Institute of Scientific and Technical Information of China (English)

    季韬; 张彬彬; 陈永波; 庄一舟

    2014-01-01

    The cracking behavior of lightweight aggregate concrete (LWAC) was investigated by mechanical analysis, SEM and cracking-resistant test where a shrinkage-restrained ring with a clapboard was used. The relationship between the ceramsite type and the cracking resistance of LWAC was built up and compared with that of normal-weight coarse aggregate concrete (NWAC). A new method was proposed to evaluate the cracking resistance of concrete, where the concepts of cracking coefficient ζt(t) and the evaluation index Acr(t) were proposed, and the development of micro-cracks and damage accumulation were recognized. For the concrete with an ascending cracking coefficient curve, the larger Acr(t) is, the lower cracking resistance of concrete is. For the concrete with a descending cracking coefficient curve, the larger Acr(t) is, the stronger the cracking resistance of concrete is. The evaluation results show that in the case of that all the three types of coarse aggregates in concrete are pre-soaked for 24 h, NWAC has the lowest cracking resistance, followed by the LWAC with lower water absorption capacity ceramsite and the LWAC with higher water absorption capacity ceramsite has the strongest cracking resistance. The proposed method has obvious advantages over the cracking age method, because it can evaluate the cracking behavior of concrete even if the concrete has not an observable crack.