Science.gov

Sample records for active array technology

  1. Active aperture phased arrays

    NASA Astrophysics Data System (ADS)

    Shenoy, R. P.

    1989-04-01

    Developments towards the realization of active aperture phased arrays are reviewed. The technology and cost aspects of the power amplifier and phase shifter subsystems are discussed. Consideration is given to research concerning T/R modules, MESFETs, side lobe control, beam steering, optical control techniques, and printed circuit antennas. Methods for configuring the array are examined, focusing on the tile and brick configurations. It is found that there is no technological impediment for introducing active aperture phased arrays.

  2. Progress of the array laser detonation technology

    NASA Astrophysics Data System (ADS)

    Ren, Peng; Zhang, Rui; He, Ai-feng; Wang, Hao-yu

    2016-01-01

    This paper stated the main characteristics of the array laser technology, introduced high application and development at home and abroad, especially having a comparison of solid array laser technology with semiconductor array laser technology on fast initiation and fire energy, etc. by researchment of the array laser technology, this paper forsaw the prospect of the array laser. at last, this paper summaries plenty of advantages of the laser array technology on miniaturization, intellectualization, integration.

  3. Comparative Analysis of Human and Rodent Brain Primary Neuronal Culture Spontaneous Activity Using Micro-Electrode Array Technology.

    PubMed

    Napoli, Alessandro; Obeid, Iyad

    2016-03-01

    Electrical activity in embryonic brain tissue has typically been studied using Micro Electrode Array (MEA) technology to make dozens of simultaneous recordings from dissociated neuronal cultures, brain stem cell progenitors, or brain slices from fetal rodents. Although these rodent neuronal primary culture electrical properties are mostly investigated, it has not been yet established to what extent the electrical characteristics of rodent brain neuronal cultures can be generalized to those of humans. A direct comparison of spontaneous spiking activity between rodent and human primary neurons grown under the same in vitro conditions using MEA technology has never been carried out before and will be described in the present study. Human and rodent dissociated fetal brain neuronal cultures were established in-vitro by culturing on a glass grid of 60 planar microelectrodes neurons under identical conditions. Three different cultures of human neurons were produced from tissue sourced from a single aborted fetus (at 16-18 gestational weeks) and these were compared with seven different cultures of embryonic rat neurons (at 18 gestational days) originally isolated from a single rat. The results show that the human and rodent cultures behaved significantly differently. Whereas the rodent cultures demonstrated robust spontaneous activation and network activity after only 10 days, the human cultures required nearly 40 days to achieve a substantially weaker level of electrical function. These results suggest that rat neuron preparations may yield inferences that do not necessarily transfer to humans.

  4. Evaluation of space station solar array technology

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The research concerning lightweight solar array assemblies since 1970 is reported. A bibliography of abstracts of documents used for reference during this period is included along with an evaluation of available solar array technology. A list of recommended technology programs is presented.

  5. [Array technology in skin pharmacology and allergology].

    PubMed

    Baron, J M; Merk, H F; Heise, R

    2003-04-01

    Because of their variable application, microarrays are currently used in different areas of research and development, such as skin pharmacology and allergology. Microarrays are plane carriers, on whose surface a variety of known DNA-molecules and proteins were immobilised. Transcripts can be detected by cDNA- and oligonucleotid-arrays and proteins of activated genes can be discovered using antibody microarrays. Detection of allergen-specific IgE from human serum can be performed using allergen chips. Since many details of the molecular mechanism and pathogenesis of skin cancer and inflammatory skin diseases and the effect of xenobiotics on cells of the human skin are still not known, array-technologies are a powerful tool to identify novel marker genes and offer the possibility of develop new therapeutic strategies as well as prognosis- and diagnosis-systems.

  6. Active membrane phased array radar

    NASA Technical Reports Server (NTRS)

    Moussessian, Alina; Del Castillo, Linda; Huang, John; Sadowy, Greg; Hoffman, James; Smith, Phil; Hatake, Toshiro; Derksen, Chuck; Lopez, Bernardo; Caro, Ed

    2005-01-01

    We have developed the first membrane-based active phased array in L-band (1.26GHz). The array uses membrane compatible Transmit/Receive (T/R) modules (membrane T/R) for each antenna element. We use phase shifters within each T/R module for electronic beam steering. We will discuss the T/R module design and integration with the membrane, We will also present transmit and receive beam-steering results for the array.

  7. Broadband Electric-Field Sensor Array Technology

    DTIC Science & Technology

    2012-08-05

    and lithium niobate is a promising technology for broadband electric field sensor arrays. The results of this research program advance the state-of...interfaces without the use of an intermediate layer. Direct bonding typically requires very flat surfaces, demanding process technology , and...REPORT Broadband Electric-Field Sensor Array Technology 14. ABSTRACT 16. SECURITY CLASSIFICATION OF: We report the development of a broadband electric

  8. A 20 GHz Active Receive Slot Array

    NASA Technical Reports Server (NTRS)

    Tulintseff, A. N.; Lee, K.; Sukamto, L.; Chew, W.

    1994-01-01

    A 20 GHz active receive slot array has been developed for operation in the downlink frequency band of NASA's Advanced Communication Technology Satellite (ACTS) for the ACTS Mobile Terminal (AMT) project. The AMT is to demonstrate voice and data communication between a mobile terminal in Los Angeles, California, and a fixed terminal in Cleveland, Ohio, via the ACTS satellite.

  9. Mass properties survey of solar array technologies

    NASA Technical Reports Server (NTRS)

    Kraus, Robert

    1991-01-01

    An overview of the technologies, electrical performance, and mass characteristics of many of the presently available and the more advanced developmental space solar array technologies is presented. Qualitative trends and quantitative mass estimates as total array output power is increased from 1 kW to 5 kW at End of Life (EOL) from a single wing are shown. The array technologies are part of a database supporting an ongoing solar power subsystem model development for top level subsystem and technology analyses. The model is used to estimate the overall electrical and thermal performance of the complete subsystem, and then calculate the mass and volume of the array, batteries, power management, and thermal control elements as an initial sizing. The array types considered here include planar rigid panel designs, flexible and rigid fold-out planar arrays, and two concentrator designs, one with one critical axis and the other with two critical axes. Solar cell technologies of Si, GaAs, and InP were included in the analyses. Comparisons were made at the array level; hinges, booms, harnesses, support structures, power transfer, and launch retention mountings were included. It is important to note that the results presented are approximations, and in some cases revised or modified performance and mass estimates of specific designs.

  10. Array Technology for Terahertz Imaging

    NASA Technical Reports Server (NTRS)

    Reck, Theodore; Siles, Jose; Jung, Cecile; Gill, John; Lee, Choonsup; Chattopadhyay, Goutam; Mehdi, Imran; Cooper, Ken

    2012-01-01

    Heterodyne terahertz (0.3 - 3THz) imaging systems are currently limited to single or a low number of pixels. Drastic improvements in imaging sensitivity and speed can be achieved by replacing single pixel systems with an array of detectors. This paper presents an array topology that is being developed at the Jet Propulsion Laboratory based on the micromachining of silicon. This technique fabricates the array's package and waveguide components by plasma etching of silicon, resulting in devices with precision surpassing that of current metal machining techniques. Using silicon increases the versatility of the packaging, enabling a variety of orientations of circuitry within the device which increases circuit density and design options. The design of a two-pixel transceiver utilizing a stacked architecture is presented that achieves a pixel spacing of 10mm. By only allowing coupling from the top and bottom of the package the design can readily be arrayed in two dimensions with a spacing of 10mm x 18mm.

  11. Phased Array Theory and Technology

    DTIC Science & Technology

    1981-07-01

    drive the ferrite magnetization to saturation as in a latching phase shifter, or to various points on the magnetization curve with flux drive...can vary from 1 kW to as much as 150 kW peak and average power levels to 400 W. Latching phase shifters have switching times un the order of one...Circuits , and Toroid Ferrite Phase Shifted SO. ode \\rrav Network 26. Dual Slat . 27. PA\\ E PAWS Array (Courtesy of Raytheon Company) 28. Patriot

  12. Stretched Lens Array Squarerigger (SLASR) Technology Maturation

    NASA Technical Reports Server (NTRS)

    O'Neill, Mark; McDanal, A.J.; Howell, Joe; Lollar, Louis; Carrington, Connie; Hoppe, David; Piszczor, Michael; Suszuki, Nantel; Eskenazi, Michael; Aiken, Dan; Fulton, Michael; Brandhorst, Henry; Schuller, Michael

    2007-01-01

    Since April 2005, our team has been underway on a competitively awarded program sponsored by NASA s Exploration Systems Mission Directorate to develop, refine, and mature the unique solar array technology known as Stretched Lens Array SquareRigger (SLASR). SLASR offers an unprecedented portfolio of performance metrics, SLASR offers an unprecedented portfolio of performance metrics, including the following: Areal Power Density = 300 W/m2 (2005) - 400 W/m2 (2008 Target) Specific Power = 300 W/kg (2005) - 500 W/kg (2008 Target) for a Full 100 kW Solar Array Stowed Power = 80 kW/cu m (2005) - 120 kW/m3 (2008 Target) for a Full 100 kW Solar Array Scalable Array Capacity = 100 s of W s to 100 s of kW s Super-Insulated Small Cell Circuit = High-Voltage (300-600 V) Operation at Low Mass Penalty Super-Shielded Small Cell Circuit = Excellent Radiation Hardness at Low Mass Penalty 85% Cell Area Savings = 75% Lower Array Cost per Watt than One-Sun Array Modular, Scalable, & Mass-Producible at MW s per Year Using Existing Processes and Capacities

  13. Stretched Lens Array Photovoltaic Concentrator Technology Developed

    NASA Technical Reports Server (NTRS)

    Piszczor, Michael F., Jr.; O'Neill, Mark J.

    2004-01-01

    Solar arrays have been and continue to be the mainstay in providing power to nearly all commercial and government spacecraft. Light from the Sun is directly converted into electrical energy using solar cells. One way to reduce the cost of future space power systems is by minimizing the size and number of expensive solar cells by focusing the sunlight onto smaller cells using concentrator optics. The stretched lens array (SLA) is a unique concept that uses arched Fresnel lens concentrators to focus sunlight onto a line of high-efficiency solar cells located directly beneath. The SLA concept is based on the Solar Concentrator Array with Refractive Linear Element Technology (SCARLET) design that was used on NASA's New Millennium Deep Space 1 mission. The highly successful asteroid/comet rendezvous mission (1998 to 2001) demonstrated the performance and long-term durability of the SCARLET/SLA solar array design and set the foundation for further improvements to optimize its performance.

  14. Technology Development for Millimeter Wave Phased Arrays.

    DTIC Science & Technology

    1987-05-01

    design would use the technology of integration-the same technology that has brought us computing power at such a low cost. The integrated phased array ...circuitry and/or the feed network, which can degrade sidelobe levels or polarization. A Two Layer Substrate Figure 2.8 shows a possible two-layer design ...feed substrates. Coupling is again through aper- tures in the ground plane of the antenna substrate. This design also allows the use of a low dielectric

  15. DNA ARRAYS: TECHNOLOGY, OPTIONS AND TOXOCOLOGICAL APPLICATIONS

    EPA Science Inventory

    DNA arrays: technology, options and toxicological applications.

    Rockett JC, Dix DJ.

    Reproductive Toxicology Division, National Health and Environmental Effects Research Laboratory, US Environmental Protection Agency, NC 27711, USA. rockett.john@epa.gov

    The hu...

  16. Anderson attractors in active arrays

    PubMed Central

    Laptyeva, Tetyana V.; Tikhomirov, Andrey A.; Kanakov, Oleg I.; Ivanchenko, Mikhail V.

    2015-01-01

    In dissipationless linear media, spatial disorder induces Anderson localization of matter, light, and sound waves. The addition of nonlinearity causes interaction between the eigenmodes, which results in a slow wave diffusion. We go beyond the dissipationless limit of Anderson arrays and consider nonlinear disordered systems that are subjected to the dissipative losses and energy pumping. We show that the Anderson modes of the disordered Ginsburg-Landau lattice possess specific excitation thresholds with respect to the pumping strength. When pumping is increased above the threshold for the band-edge modes, the lattice dynamics yields an attractor in the form of a stable multi-peak pattern. The Anderson attractor is the result of a joint action by the pumping-induced mode excitation, nonlinearity-induced mode interactions, and dissipative stabilization. The regimes of Anderson attractors can be potentially realized with polariton condensates lattices, active waveguide or cavity-QED arrays. PMID:26304462

  17. Advancements in the micromirror array projector technology

    NASA Astrophysics Data System (ADS)

    Beasley, David B.; Bender, Matt W.; Crosby, Jay; Messer, Tim; Saylor, Daniel A.

    2003-09-01

    The Micromirror Array Projector System (MAPS) is a state-of-the-art dynamic scene projector developed by Optical Sciences Corporation (OSC) for Hardware-In-the-Loop (HWIL) simulation and sensor test applications. Since the introduction of the first MAPS in 2001, OSC has continued to improve the technology and develop systems for new projection and test applications. The MAPS is based upon the Texas Instruments Digital Micromirror Device (DMD) which has been modified to project high resolution, realistic imagery suitable for testing sensors and seekers operating in the UV, visible, NIR, and IR wavebands. This paper reviews the basic design and describes recent developments and new applications of the MAPS technology. Recent developments for the MAPS include increasing the format of the micromirror array to 1024x768 and increasing the binary frame rate to 10KHz. The MAPS technology has also been applied to the design of a Mobile Extended Spectrum Electro-Optical Test Set (MESEOTS). This test set is designed for testing UV, visible, NIR and IR sensors as well as laser rangefinders, laser trackers, and laser designators. The design and performance of the improved MAPS and the MESEOTS are discussed in paper.

  18. UAVSAR Active Electronically Scanned Array

    NASA Technical Reports Server (NTRS)

    Sadowy, Gregory, A.; Chamberlain, Neil F.; Zawadzki, Mark S.; Brown, Kyle M.; Fisher, Charles D.; Figueroa, Harry S.; Hamilton, Gary A.; Jones, Cathleen E.; Vorperian, Vatche; Grando, Maurio B.

    2011-01-01

    The Uninhabited Airborne Vehicle Synthetic Aperture Radar (UAVSAR) is a pod-based, L-band (1.26 GHz), repeatpass, interferometric, synthetic aperture radar (InSAR) used for Earth science applications. Repeat-pass interferometric radar measurements from an airborne platform require an antenna that can be steered to maintain the same angle with respect to the flight track over a wide range of aircraft yaw angles. In order to be able to collect repeat-pass InSAR data over a wide range of wind conditions, UAVSAR employs an active electronically scanned array (AESA). During data collection, the UAVSAR flight software continuously reads the aircraft attitude state measured by the Embedded GPS/INS system (EGI) and electronically steers the beam so that it remains perpendicular to the flight track throughout the data collection

  19. Array Phase Shifters: Theory and Technology

    NASA Technical Reports Server (NTRS)

    Romanofsky, Robert R.

    2007-01-01

    While there are a myriad of applications for microwave phase shifters in instrumentation and metrology, power combining, amplifier linearization, and so on, the most prevalent use is in scanning phased-array antennas. And while this market continues to be dominated by military radar and tracking platforms, many commercial applications have emerged in the past decade or so. These new and potential applications span low-Earth-orbit (LEO) communications satellite constellations and collision warning radar, an aspect of the Intelligent Vehicle Highway System or Automated Highway System. In any case, the phase shifters represent a considerable portion of the overall antenna cost, with some estimates approaching 40 percent for receive arrays. Ferrite phase shifters continue to be the workhorse in military-phased arrays, and while there have been advances in thin film ferrite devices, the review of this device technology in the previous edition of this book is still highly relevant. This chapter will focus on three types of phase shifters that have matured in the past decade: GaAs MESFET monolithic microwave integrated circuit (MMIC), micro-electromechanical systems (MEMS), and thin film ferroelectric-based devices. A brief review of some novel devices including thin film ferrite phase shifters and superconducting switches for phase shifter applications will be provided. Finally, the effects of modulo 2 phase shift limitations, phase errors, and transient response on bit error rate degradation will be considered.

  20. Thermally activated technologies: Technology Roadmap

    SciTech Connect

    None, None

    2003-05-01

    The purpose of this Technology Roadmap is to outline a set of actions for government and industry to develop thermally activated technologies for converting America’s wasted heat resources into a reservoir of pollution-free energy for electric power, heating, cooling, refrigeration, and humidity control. Fuel flexibility is important. The actions also cover thermally activated technologies that use fossil fuels, biomass, and ultimately hydrogen, along with waste heat.

  1. The technology of miniature acoustic element arrays

    NASA Technical Reports Server (NTRS)

    Bom, N.; Lancee, C. T.; Ridder, J.; Ligtvoet, C.; Roelandt, J.

    1975-01-01

    Various aspects of miniature element array construction are discussed. Some initial results on optimization of lateral resolution with a special focusing technique in linear array design is presented, together with the constructional details. Furthermore the construction of a catheter tip array is treated in detail.

  2. Active floating micro electrode arrays (AFMA).

    PubMed

    Kim, T; Troyk, P R; Bak, M

    2006-01-01

    Neuroscientists have widely used metal microelectrodes inserted into the cortex to record neural signals from, and provide electrical stimulation to, neural tissue for many years. Recently, the demand for implanting electrode arrays within the cortex, for both stimulation and recording, has rapidly increased. We are developing Active-floating-micro-electrode-arrays (AFMA) that are intended for use as a multielectrode cortical interface while minimizing the number of wires leading from the array to extra-dural circuitry or connectors. When combined with a wireless module, these new microelectrode arrays should allow for simulation and recording within free-roaming animals. This paper mainly discusses the design, fabrication, and packing of the first generation AFMA. Our long-term vision is a wireless-transmission electrode system, for stimulation and recording in free-roaming animals, which uses a family of modular active implantable electrode arrays.

  3. Current Technology of the Lightning Mapping Array

    NASA Astrophysics Data System (ADS)

    Rodeheffer, D.; Rison, W.; Krehbiel, P. R.; Edens, H. E.; Thomas, R. J.

    2013-12-01

    The Lightning Mapping Array (LMA) is continuing to be developed technology-wise, involving both hardware configurations and software, to further simplify the deployment, operation and sensitivity of networks. This has included developing stations that operate on a complete standalone basis, utilizing battery backed-up solar power and cell phone data modems for connecting into the internet. Solid state disks not requiring cooling are used for onsite data storage, allowing the electronics to be housed in an RF-tight enclosure and the VHF receiving antenna to be co-located immediately above the station electronics, rather than 50 to 100 feet away. The combined changes enable stations to be placed in remote, RF-quiet locations for excellent sensitivity, and to have only a 4'x 4' freestanding footprint on the ground for ease of deployment. Networks that take advantage of the solar/cell modem design are the West Texas LMA (Texas Tech University), the Houston LMA (Texas A&M), and the North Colorado LMA (NMT/CSU), initially utilized in the 2012 DC3 atmospheric chemistry program. A similar network (operated in conjunction with NASA/MSFC) was set up on a temporary basis in Southern France leading up to the HyMeX field program in September and October of 2012. Each of the above networks is remotely monitored via the internet and feeds its data on a minute-by-minute basis back to a central processing computer at NM Tech (or TTU), where it is processed in real time and posted on the web in the two- and ten-minute time intervals. Examples of archived and current realtime data for the North Colorado LMA can be seen at http://lightning.nmt.edu/colma/ and /colma/current/. Finally, based on successful experiences with the above networks, we have developed what is termed the 'Sitetest' network, consisting of 9 or 10 stations each mounted on wooden pallets with lightweight enclosures and simple antenna hardware. The network was initially operated at Kennedy Space Center to test out

  4. Technology Learning Activities I.

    ERIC Educational Resources Information Center

    International Technology Education Association, Reston, VA.

    This guide contains 30 technology learning activities. Activities may contain all or some of the following: an introduction, objectives, materials and equipment, challenges, limitations, notes and investigations, resources and references used, and evaluation ideas. Activity titles are: (1) Occupations in Construction Technology; (2) Designing a…

  5. Large Active Retrodirective Arrays for Space Applications

    NASA Technical Reports Server (NTRS)

    Chernoff, R. C.

    1978-01-01

    An active retrodirective array (ARA) electronically points a microwave beam back at the apparent source of an incident pilot signal. Retrodirectivity is the result of phase conjugation of the pilot signal received by each element of the array. The problem of supplying the correct phase reference to the phase conjugation circuit (PCC) associated with each element of the array is solved by central phasing. By eliminating the need for structural rigidity, central phasing confers a decisive advantage on ARA's as large spaceborne antennas. A new form of central phasing suitable for very large arrays is described. ARA's may easily be modified to serve both as transmitting and receiving arrays simultaneously. Two new kinds of exact, frequency translating PCC's are described. Such PCC's provide the ARA with input-output isolation and freedom from squint. The pointing errors caused by the radial and transverse components of the ARA's velocity, by the propagation medium, and by multipath are discussed. A two element ARA breadboard was built and tested at JPL. Its performance is limited primarily by multipath induced errors.

  6. Space Photovoltaic Research and Technology 1986. High Efficiency, Space Environment, and Array Technology

    NASA Technical Reports Server (NTRS)

    1987-01-01

    The conference provided a forum to assess the progress made, the problems remaining, and the strategy for the future of photovoltaic research. Cell research and technology, space environmental effects, array technology and applications were discussed.

  7. Study of SEP solar array modifications. [technology assessment

    NASA Technical Reports Server (NTRS)

    Antonides, G. J.

    1978-01-01

    The feasibility of modifying the solar electric propulsion (SEP) 66 watt/kilogram, 12.5 kilowatt solar array blanket design to incorporate ultra-low mass blanket technology and to generate conceptual design data by modifying the SEP solar array design to 17.5kW power output was performed. Five modified designs were developed, which substituted present SEP solar array design components with one or more of 50 micron thick solar cells, 75 micron cell coverglasses, and a different blanket substrate developed by GE. A parametric analysis was performed to determine the solar array mast least weight and blanket tension required to maintain a minimum natural frequency of 0.04 Hz. The solar array wing assembly weights and power outputs were calculated, and preliminary cost estimates for flight hardware development, fabrication and qualification were made for each case studied.

  8. Solar Cell and Array Technology Development for NASA Solar Electric Propulsion Missions

    NASA Technical Reports Server (NTRS)

    Piszczor, Michael; McNatt, Jeremiah; Mercer, Carolyn; Kerslake, Tom; Pappa, Richard

    2012-01-01

    NASA is currently developing advanced solar cell and solar array technologies to support future exploration activities. These advanced photovoltaic technology development efforts are needed to enable very large (multi-hundred kilowatt) power systems that must be compatible with solar electric propulsion (SEP) missions. The technology being developed must address a wide variety of requirements and cover the necessary advances in solar cell, blanket integration, and large solar array structures that are needed for this class of missions. Th is paper will summarize NASA's plans for high power SEP missions, initi al mission studies and power system requirements, plans for advanced photovoltaic technology development, and the status of specific cell and array technology development and testing that have already been conducted.

  9. High-power, ultralow-mass solar arrays: FY-77 solar arrays technology readiness assessment report, volume 2

    NASA Technical Reports Server (NTRS)

    Costogue, E. N.; Young, L. E.; Brandhorst, H. W., Jr.

    1978-01-01

    Development efforts are reported in detail for: (1) a lightweight solar array system for solar electric propulsion; (2) a high efficiency thin silicon solar cell; (3) conceptual design of 200 W/kg solar arrays; (4) fluorocarbon encapsulation for silicon solar cell array; and (5) technology assessment of concentrator solar arrays.

  10. Jansky Very Large Array: technology advancing science

    NASA Astrophysics Data System (ADS)

    Carilli, Christopher

    2015-08-01

    Over the last decade, the NRAO has completed on time, and on budget, a major reconstruction of the Very Large Array. Building on existing infrastructure to maximize efficiency, the entire VLA electronics system, including correlator, receivers, data transmission, and monitor and control, have been replaced with state of the art systems. This complete rebuild establishes the new Jansky VLA, operating between 75MHz and 50GHz, as the most powerful radio telescope in the world for the coming decade.I will review the technical improvements of the array, including:- Correlator: Increased bandwidth from 100MHz to 8GHz, with thousands of spectral channels.- Receivers: replaced the previous narrow bands with receivers covering the full frequency range from 1 GHz to 50GHz. New systems are also being tested to cover from 50MHz to 400MHz.- Data transmission: 8GHz over optical fiber out to 30km.I will then highlight some of the science enabled by these improvements, including:- Large cosmic volume searches for atomic and molecular gas, from the nearby Universe to the most distant galaxies, plus kpc-scale imaging of the cool gas in distant starburst galaxies.- High resolution studies of star and planet formation.- Innovative interferometric searches for transient phenomena.- The first radio continuum deep fields with sensitivities < 1uJy, with full polarization for Faraday tomography.- Imaging radio-mode feedback in galaxies and clusters, and delineating the complex plasma physical processes involved on scales from a few kpc to hundreds of kpc.I will conclude with a few words about the major challenges facing such a new instrument. These challenges are all on the critical path toward any successful development of future facilities, such as the next generation VLA and SKA:- Big data: data volumes and post-processing are currently major bottlenecks in the turn-over from observation to science publication. NRAO is developing calibration and imaging pipelines to provide science

  11. Technology Systems. Laboratory Activities.

    ERIC Educational Resources Information Center

    Brame, Ray; And Others

    This guide contains 43 modules of laboratory activities for technology education courses. Each module includes an instructor's resource sheet and the student laboratory activity. Instructor's resource sheets include some or all of the following elements: module number, course title, activity topic, estimated time, essential elements, objectives,…

  12. Extravehicular activity technology discipline

    NASA Technical Reports Server (NTRS)

    Webbon, Bruce W.

    1990-01-01

    Viewgraphs on extravehicular activity technology discipline for Space Station Freedom are presented. Topics covered include: extravehicular mobility unit; airlock and EMU support equipment; tools, mobility aids, and workstations; and telerobotic work aids interfaces.

  13. Application of MEMS Microphone Array Technology to Airframe Noise Measurements

    NASA Technical Reports Server (NTRS)

    Humphreys, William M., Jr.; Shams, Qamar A.; Graves, Sharon S.; Sealey, Bradley S.; Bartram, Scott M.; Comeaux, Toby

    2005-01-01

    Current generation microphone directional array instrumentation is capable of extracting accurate noise source location and directivity data on a variety of aircraft components, resulting in significant gains in test productivity. However, with this gain in productivity has come the desire to install larger and more complex arrays in a variety of ground test facilities, creating new challenges for the designers of array systems. To overcome these challenges, a research study was initiated to identify and develop hardware and fabrication technologies which could be used to construct an array system exhibiting acceptable measurement performance but at much lower cost and with much simpler installation requirements. This paper describes an effort to fabricate a 128-sensor array using commercially available Micro-Electro-Mechanical System (MEMS) microphones. The MEMS array was used to acquire noise data for an isolated 26%-scale high-fidelity Boeing 777 landing gear in the Virginia Polytechnic Institute and State University Stability Tunnel across a range of Mach numbers. The overall performance of the array was excellent, and major noise sources were successfully identified from the measurements.

  14. Active and passive cooling for concentrating photovoltaic arrays

    SciTech Connect

    Edenburn, M.W.

    1981-10-01

    Optimization, based on minimum energy cost, of active and passive cooling designs for point-focus Fresnel lens photovoltaic arrays and line-focus, parabolic-trough photovoltaic arrays is discussed, and the two types of cooling are compared. Passive cooling is more cost-effective for Fresnel lens arrays while the reverse is true for parabolic-trough arrays.

  15. An Active K-Band Receive Slot Array for Mobile Satellite Communications

    NASA Technical Reports Server (NTRS)

    Tulintseff, A. N.; Lee, K. A.; Sukamto, L. M.; Chew, W.

    1994-01-01

    An active receive slot array has been developed for operation in the downlink frequency band, 19.914-20.064 GHz, of NASA's Advanced Communication Technology Satellite (ACTS) for the ACTS Mobile Terminal (AMT) project.

  16. NORMAL NASAL GENE EXPRESSION LEVELS USING CDNA ARRAY TECHNOLOGY

    EPA Science Inventory

    Normal Nasal Gene Expression Levels Using cDNA Array Technology.

    The nasal epithelium is a target site for chemically-induced toxicity and carcinogenicity. To detect and analyze genetic events which contribute to nasal tumor development, we first defined the gene expressi...

  17. Trimodal nanoelectrode array for precise deep brain stimulation: prospects of a new technology based on carbon nanofiber arrays.

    PubMed

    Li, J; Andrews, R J

    2007-01-01

    Although deep brain stimulation (DBS) has recently been shown to be effective for neurological disorders such as Parkinson's disease, there are many limitations of the current technology: the large size of current microelectrodes (approximately 1 mm diameter); the lack of monitoring of local brain electrical activity and neurotransmitters (e.g. dopamine in Parkinson's disease); the open-loop nature of the stimulation (i.e. not guided by brain electrochemical activity). Reducing the size of the monitoring and stimulating electrodes by orders of magnitude (to the size of neural elements) allows remarkable improvements in both monitoring (spatial resolution, temporal resolution, and sensitivity) and stimulation. Carbon nanofiber nanoelectrode technology offers the possibility of trimodal arrays (monitoring electrical activity, monitoring neurotransmitter levels, precise stimulation). DBS can then be guided by changes in brain electrical activity and/or neurotransmitter levels (i.e. closed-loop DBS). Here, we describe the basic manufacture and electrical characteristics of a prototype nanoelectrode array for DBS, as well as preliminary studies with electroconductive polymers necessary to optimize DBS in vivo. An approach such as the nanoelectrode array described here may offer a generic electrical-neural interface for use in various neural prostheses.

  18. Study of large adaptive arrays for space technology applications

    NASA Technical Reports Server (NTRS)

    Berkowitz, R. S.; Steinberg, B.; Powers, E.; Lim, T.

    1977-01-01

    The research in large adaptive antenna arrays for space technology applications is reported. Specifically two tasks were considered. The first was a system design study for accurate determination of the positions and the frequencies of sources radiating from the earth's surface that could be used for the rapid location of people or vehicles in distress. This system design study led to a nonrigid array about 8 km in size with means for locating the array element positions, receiving signals from the earth and determining the source locations and frequencies of the transmitting sources. It is concluded that this system design is feasible, and satisfies the desired objectives. The second task was an experiment to determine the largest earthbound array which could simulate a spaceborne experiment. It was determined that an 800 ft array would perform indistinguishably in both locations and it is estimated that one several times larger also would serve satisfactorily. In addition the power density spectrum of the phase difference fluctuations across a large array was measured. It was found that the spectrum falls off approximately as f to the minus 5/2 power.

  19. Tailorable chiroptical activity of metallic nanospiral arrays

    NASA Astrophysics Data System (ADS)

    Deng, Junhong; Fu, Junxue; Ng, Jack; Huang, Zhifeng

    2016-02-01

    The engineering of the chiroptical activity of the emerging chiral metamaterial, metallic nanospirals, is in its infancy. We utilize glancing angle deposition (GLAD) to facilely sculpture the helical structure of silver nanospirals (AgNSs), so that the scope of chiroptical engineering factors is broadened to include the spiral growth of homochiral AgNSs, the combination of left- and right-handed helical chirality to create heterochiral AgNSs, and the coil-axis alignment of the heterochiral AgNSs. It leads to flexible control over the chiroptical activity of AgNS arrays with respect to the sign, resonance wavelength and amplitude of circular dichroism (CD) in the UV and visible regime. The UV chiroptical mode has a distinct response from the visible mode. Finite element simulation together with LC circuit theory illustrates that the UV irradiation is mainly adsorbed in the metal and the visible is preferentially scattered by the AgNSs, accounting for the wavelength-related chiroptical distinction. This work contributes to broadening the horizons in understanding and engineering chiroptical responses, primarily desired for developing a wide range of potential chiroplasmonic applications.The engineering of the chiroptical activity of the emerging chiral metamaterial, metallic nanospirals, is in its infancy. We utilize glancing angle deposition (GLAD) to facilely sculpture the helical structure of silver nanospirals (AgNSs), so that the scope of chiroptical engineering factors is broadened to include the spiral growth of homochiral AgNSs, the combination of left- and right-handed helical chirality to create heterochiral AgNSs, and the coil-axis alignment of the heterochiral AgNSs. It leads to flexible control over the chiroptical activity of AgNS arrays with respect to the sign, resonance wavelength and amplitude of circular dichroism (CD) in the UV and visible regime. The UV chiroptical mode has a distinct response from the visible mode. Finite element simulation

  20. Application of visible linear array technology to earth observation sensors

    NASA Technical Reports Server (NTRS)

    Noll, R. E.; Tracy, R. A.

    1975-01-01

    The present paper identifies the systems engineering aspects of applying solid-state technology to earth observations applications being traditionally performed by point (or multiple-point) detector line scanned mechanisms. It is shown that the translation from a basically serial data flow point-detector mechanically-scanned sensor to a solid state highly parallel linear-array pushbroom sensor results in minimizing mechanical complexity and maximizing electronics complexity, with increased demands upon optical performance in some applications. Technical aspects relevant to highly parallel photodiode linear-array pushbroom applications are discussed. Examples of systems engineering applications are provided.

  1. Active and passive cooling for concentrating photovoltaic arrays

    SciTech Connect

    Edenburn, M.W.

    1980-01-01

    The optimization, based on minimum energy cost, of active and passive cooling designs for point-focus Fresnel lens photovoltaic arrays and line-focus, parabolic-trough photovoltaic arrays are discussed, and the two types of cooling are compared. Passive cooling is more cost effective than active for Fresnel lens arrays while the reverse is true for parabolic trough arrays. The analysis produced several other conclusions of interest which are also discussed.

  2. Array of Laminated Waveguides for Implementation in LTCC Technology

    DTIC Science & Technology

    2006-11-01

    A novel coaxial-to- waveguide transition has also been designed as feed port for measuring the prototypes. The design , analysis , fabrication process...1 1.2 Simulation and measurement results for the laminated waveguide elements .. 3 2. Analysis of the five-element array ...technology. A novel coaxial-to- waveguide transition has also been designed as feed port for measuring the prototypes. The design , analysis

  3. Hollow Nanospheres Array Fabrication via Nano-Conglutination Technology.

    PubMed

    Zhang, Man; Deng, Qiling; Xia, Liangping; Shi, Lifang; Cao, Axiu; Pang, Hui; Hu, Song

    2015-09-01

    Hollow nanospheres array is a special nanostructure with great applications in photonics, electronics and biochemistry. The nanofabrication technique with high resolution is crucial to nanosciences and nano-technology. This paper presents a novel nonconventional nano-conglutination technology combining polystyrenes spheres (PSs) self-assembly, conglutination and a lift-off process to fabricate the hollow nanospheres array with nanoholes. A self-assembly monolayer of PSs was stuck off from the quartz wafer by the thiol-ene adhesive material, and then the PSs was removed via a lift-off process and the hollow nanospheres embedded into the thiol-ene substrate was obtained. Thiolene polymer is a UV-curable material via "click chemistry" reaction at ambient conditions without the oxygen inhibition, which has excellent chemical and physical properties to be attractive as the adhesive material in nano-conglutination technology. Using the technique, a hollow nanospheres array with the nanoholes at the diameter of 200 nm embedded into the rigid thiol-ene substrate was fabricated, which has great potential to serve as a reaction container, catalyst and surface enhanced Raman scattering substrate.

  4. Active Vibration Damping of Solar Arrays

    NASA Astrophysics Data System (ADS)

    Reinicke, Gunar; Baier, Horst; Grillebeck, Anton; Scharfeld, Frank; Hunger, Joseph; Abou-El-Ela, A.; Lohberg, Andreas

    2012-07-01

    Current generations of large solar array panels are lightweight and flexible constructions to reduce net masses. They undergo strong vibrations during launch. The active vibration damping is one convenient option to reduce vibration responses and limit stresses in facesheets. In this study, two actuator concepts are used for vibration damping. A stack interface actuator replaces a panel hold down and is decoupled from bending moments and shear forces. Piezoelectric patch actuators are used as an alternative, where the number, position and size of actuators are mainly driven by controllability analyses. Linear Quadratic Gaussian control is used to attenuate vibrations of selected mode shapes with both actuators. Simulations as well as modal and acoustic tests show the feasibility of selected actuator concepts.

  5. Space Photovoltaic Research and Technology 1985: High Efficiency, Space Environment, and Array Technology

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The seventh NASA Conference on Space Photovoltaic Research and Technology was held at NASA Lewis Research Center, Cleveland, Ohio, from 30 April until 2 May 1985. Its purpose was to assess the progress made, the problems remaining, and future strategy for space photovoltaic research. Particular emphasis was placed on high efficiency, space environment, and array technology.

  6. Array-on-Array Strategy For Activity-Based Enzyme Profiling.

    PubMed

    Sieow, Brendan Fu-Long; Uttamchandani, Mahesh

    2017-01-01

    We describe a novel array on array strategy intended to enhance the throughput of enzymatic activity screening using microarrays. This strategy consists of spotting a first array with large droplets of enzymes with varying concentrations and subsequently spotting a second array with small droplets of fluorogenic substrate on top of the enzyme array. By varying the array on array spotting patterns of different classes of enzyme (e.g., proteases, phosphatases, kinases) and their corresponding fluorogenic substrates, we have the unprecedented ability for testing enzymes and mixed samples in a multiplexed fashion within a single microarray slide. This new approach enables rapid enzyme characterization building upon a one enzyme on one slide droplet-based screening concept previously established.

  7. Coherent combining technology of master oscillator power amplifier fiber arrays.

    PubMed

    Xiao, R; Hou, J; Liu, M; Jiang, Z F

    2008-02-04

    Coherent beam combination of fiber laser array is an important technology of realize high-power, high-radiance fiber laser system. In this paper, Master Oscillator-Power Amplifier scheme is used to realize phase controlling of three ytterbium fiber amplifiers, the experiment results of both two and three fiber amplifiers are given and compared. Far-field patterns with different fill factor are studied experimentally. We perform optical phase-noise measurements of a commercial 1-W ytterbium fiber amplifier using our phase control electronics, the dominant phase noises of the 1-W fiber amplifier are at frequencies below one kilohertz.

  8. Phased-array-fed antenna configuration study. Volume 1: Technology assessment

    NASA Technical Reports Server (NTRS)

    Sorbello, R. M.; Zaghloul, A. I.; Lee, B. S.; Siddiqi, S.; Geller, B. D.; Gerson, H. I.; Srinivas, D. N.

    1983-01-01

    The status of the technologies for phased-array-fed dual reflector systems is reviewed. The different aspects of these technologies, including optical performances, phased array systems, problems encountered in phased array design, beamforming networks, MMIC design and its incorporation into waveguide systems, reflector antenna structures, and reflector deployment mechanisms are addressed.

  9. Graphene microelectrode arrays for neural activity detection.

    PubMed

    Du, Xiaowei; Wu, Lei; Cheng, Ji; Huang, Shanluo; Cai, Qi; Jin, Qinghui; Zhao, Jianlong

    2015-09-01

    We demonstrate a method to fabricate graphene microelectrode arrays (MEAs) using a simple and inexpensive method to solve the problem of opaque electrode positions in traditional MEAs, while keeping good biocompatibility. To study the interface differences between graphene-electrolyte and gold-electrolyte, graphene and gold electrodes with a large area were fabricated. According to the simulation results of electrochemical impedances, the gold-electrolyte interface can be described as a classical double-layer structure, while the graphene-electrolyte interface can be explained by a modified double-layer theory. Furthermore, using graphene MEAs, we detected the neural activities of neurons dissociated from Wistar rats (embryonic day 18). The signal-to-noise ratio of the detected signal was 10.31 ± 1.2, which is comparable to those of MEAs made with other materials. The long-term stability of the MEAs is demonstrated by comparing differences in Bode diagrams taken before and after cell culturing.

  10. Mars Array Technology Experiment Developed to Test Solar Arrays on Mars

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.

    2001-01-01

    Solar arrays will be the power supply for future missions to the planet Mars, including landers, rovers, and eventually human missions to explore the Martian surface. Until Mars Pathfinder landed in July 1997, no solar array had been used on the surface. The MATE package is intended to measure the solar energy reaching the surface, characterize the Martian environment to gather the baseline information required for designing power systems for long-duration missions, and to quantify the performance and degradation of advanced solar cells on the Martian surface. To measure the properties of sunlight reaching the Martian surface, MATE incorporates two radiometers and a visible/NIR spectrometer. The radiometers consist of multiple thermocouple junctions using thin-film technology. These devices generate a voltage proportional to the solar intensity. One radiometer measures the global broadband solar intensity, including both the direct and scattered sunlight, with a field of view of approximately 130. The second radiometer incorporates a slit to measure the direct (unscattered) intensity radiation. The direct radiometer can only be read once per day, with the Sun passing over the slit. The spectrometer measures the global solar spectrum with two 256-element photodiode arrays, one Si sensitive in the visible range (300 to 1100 nm), and a second InGaAs sensitive to the near infrared (900 to 1700 nm). This range covers 86 percent of the total energy from the Sun, with approximately 5-nm resolution. Each photodiode array has its own fiber-optic feed and grating. Although the purpose of the MATE is to gather data useful in designing solar arrays for Mars surface power systems, the radiometer and spectrometer measurements are expected to also provide important scientific data for characterizing the properties of suspended atmospheric dust. In addition to measuring the solar environment of Mars, MATE will measure the performance of five different individual solar cell types

  11. Silicon technologies for arrays of Single Photon Avalanche Diodes

    PubMed Central

    Ceccarelli, Francesco; Rech, Ivan; Ghioni, Massimo

    2016-01-01

    In order to fulfill the requirements of many applications, we recently developed a new technology aimed at combining the advantages of traditional thin and thick silicon Single Photon Avalanche Diodes (SPAD). In particular we demonstrated single-pixel detectors with a remarkable improvement in the Photon Detection Efficiency in the red/near-infrared spectrum (e.g. 40% at 800nm) while maintaining a timing jitter better than 100ps. In this paper we discuss the limitations of such Red-Enhanced (RE) technology from the point of view of the fabrication of small arrays of SPAD and we propose modifications to the structure aimed at overcoming these issues. We also report the first preliminary experimental results attained on devices fabricated adopting the improved structure. PMID:27761058

  12. Oligonucleotide-arrayed TFT photosensor applicable for DNA chip technology.

    PubMed

    Tanaka, Tsuyoshi; Hatakeyama, Keiichi; Sawaguchi, Masahiro; Iwadate, Akihito; Mizutani, Yasushi; Sasaki, Kazuhiro; Tateishi, Naofumi; Takeyama, Haruko; Matsunaga, Tadashi

    2006-09-05

    A thin film transistor (TFT) photosensor fabricated by semiconductor integrated circuit (IC) technology was applied to DNA chip technology. The surface of the TFT photosensor was coated with TiO2 using a vapor deposition technique for the fabrication of optical filters. The immobilization of thiolated oligonucleotide probes onto a TiO2-coated TFT photosensor using gamma-aminopropyltriethoxysilane (APTES) and N-(gamma-maleimidobutyloxy) sulfosuccinimide ester (GMBS) was optimized. The coverage value of immobilized oligonucleotides reached a plateau at 33.7 pmol/cm2, which was similar to a previous analysis using radioisotope-labeled oligonucleotides. The lowest detection limits were 0.05 pmol/cm2 for quantum dot and 2.1 pmol/cm2 for Alexa Fluor 350. Furthermore, single nucleotide polymorphism (SNP) detection was examined using the oligonucleotide-arrayed TFT photosensor. A SNP present in the aldehyde dehydrogenase 2 (ALDH2) gene was used as a target. The SNPs in ALDH2*1 and ALDH2*2 target DNA were detected successfully using the TFT photosensor. DNA hybridization in the presence of both ALDH2*1 and ALDH2*2 target DNA was observed using both ALDH2*1 and ALDH2*2 detection oligonucleotides-arrayed TFT photosensor. Use of the TFT photosensor will allow the development of a disposable photodetecting device for DNA chip systems.

  13. Active Control of Noise Using Actuator/Sensor Arrays

    NASA Technical Reports Server (NTRS)

    Lindner, Douglas K.; Winder, Patrice; Kirby, George

    1996-01-01

    Current research in smart structures is directed toward the integration of many actuators and sensors into a material. In this paper we investigate the possibility of using this instrumentation for active noise control from a vibrating structures. Current technology for reducing radiated sound is limited by the instrumentation for the control system. These control systems employ relatively small numbers of sensors and actuators. Hence, these control systems must rely on a model of the structure to estimate and control the global vibrations that contribute to the far field pressure. For complex, realistic structures the development of such a model is a formidable task. The model is a limiting factor in the continuing development of structural acoustics. In this paper we propose to increase the number of actuators and sensors of a smart material to offset the complexity of the model used for control design. The sensor arrays will be used to directly sense the shape of the structure rather than using a model of the structures to indirectly sense the shape of the structure. The actuator array is used to apply distributed forces to the structure, rather than using the structure itself as a load path. A control system for the active cancellation of sound is derived from standard control system methodologies.

  14. SEPS solar array design and technology evaluation. [Solar Electric Propulsion Stage

    NASA Technical Reports Server (NTRS)

    Elms, R. V., Jr.; Young, L. E.

    1975-01-01

    The solar array system considered is composed of two wings. Each wing consists of a solar array blanket, a blanket launch storage container, an extension/retraction mast assembly, a blanket tensioning system, and an array electrical harness. A technology evaluation is performed to assess the applicable solar array state-of-the-art and to define the supporting effort necessary to achieve technology readiness for meeting the Solar Electric Propulsion Stage (SEPS) solar array design requirements. Details of mechanical design are discussed along with questions of electrical design, operational reliability advantages, and array assembly advantages.

  15. Active alignment scheme for the MPTS array

    SciTech Connect

    Iwasaki, R.

    1980-01-01

    In order to maximize the efficiency of the microwave power transmission system (MPTS), the surface of the array antenna must be extremely flat, which is difficult to achieve using passive techniques over the 1 km dimensions of the array. In order to achieve and maintain this required flatness, a rotating laser beam used for leveling applications on earth has been utilized as a reference system. A photoconductive sensor with a reflective collecting surface is used to determine the displacement and polarity of any misalignment and automatically engage a stepping motor to drive a variable-length mechanism to make the necessary corrections. A three-point subarray alignment arrangement is described which independently adjusts, in the three orthogonal directions, the height and tilt of subarrays within the MPTS array and readily adapts to any physical distortions of the secondary structure (such as that resulting from severe temperature extremes caused by an eclipse of the sun.

  16. Detail of array panels, Face B, with active and terminated ...

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

    Detail of array panels, Face B, with active and terminated dipole elements - Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Techinical Equipment Building, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  17. THz Direct Detector and Heterodyne Receiver Arrays in Silicon Nanoscale Technologies

    NASA Astrophysics Data System (ADS)

    Grzyb, Janusz; Pfeiffer, Ullrich

    2015-10-01

    The main scope of this paper is to address various implementation aspects of THz detector arrays in the nanoscale silicon technologies operating at room temperatures. This includes the operation of single detectors, detectors operated in parallel (arrays), and arrays of detectors operated in a video-camera mode with an internal reset to support continuous-wave illumination without the need to synchronize the source with the camera (no lock-in receiver required). A systematic overview of the main advantages and limitations in using silicon technologies for THz applications is given. The on-chip antenna design challenges and co-design aspects with the active circuitry are thoroughly analyzed for broadband detector/receiver operation. A summary of the state-of-the-art arrays of broadband THz direct detectors based on two different operation principles is presented. The first is based on the non-quasistatic resistive mixing process in a MOSFET channel, whereas the other relies on the THz signal rectification by nonlinearity of the base-emitter junction in a high-speed SiGe heterojunction bipolar transistor (HBT). For the MOSFET detector arrays implemented in a 65 nm bulk CMOS technology, a state-of-the-art optical noise equivalent power (NEP) of 14 pW/ at 720 GHz was measured, whereas for the HBT detector arrays in a 0.25 μm SiGe process technology, an optical NEP of 47 pW/ at 700 GHz was found. Based on the implemented 1k-pixel CMOS camera with an average power consumption of 2.5 μW/pixel, various design aspects specific to video-mode operation are outlined and co-integration issues with the readout circuitry are analyzed. Furthermore, a single-chip 2 × 2 array of heterodyne receivers for multi-color active imaging in a 160-1000 GHz band is presented with a well-balanced NEP across the operation bandwidth ranging from 0.1 to 0.24 fW/Hz (44.1-47.8 dB single-sideband NF) and an instantaneous IF bandwidth of 10 GHz. In its present implementation, the receiver RF

  18. The Implementation of Advanced Solar Array Technology in Future NASA Missions

    NASA Technical Reports Server (NTRS)

    Piszczor, Michael F.; Kerslake, Thomas W.; Hoffman, David J.; White, Steve; Douglas, Mark; Spence, Brian; Jones, P. Alan

    2003-01-01

    Advanced solar array technology is expected to be critical in achieving the mission goals on many future NASA space flight programs. Current PV cell development programs offer significant potential and performance improvements. However, in order to achieve the performance improvements promised by these devices, new solar array structures must be designed and developed to accommodate these new PV cell technologies. This paper will address the use of advanced solar array technology in future NASA space missions and specifically look at how newer solar cell technologies impact solar array designs and overall power system performance.

  19. Microstrip technology and its application to phased array compensation

    NASA Technical Reports Server (NTRS)

    Dudgeon, J. E.; Daniels, W. D.

    1972-01-01

    A systematic analysis of mutual coupling compensation using microstrip techniques is presented. A method for behind-the-array coupling of a phased antenna array is investigated as to its feasibility. The matching scheme is tried on a rectangular array of one half lambda 2 dipoles, but it is not limited to this array element or geometry. In the example cited the values of discrete components necessary were so small an L-C network is needed for realization. Such L-C tanks might limit an otherwise broadband array match, however, this is not significant for this dipole array. Other areas investigated were balun feeding and power limits of spiral antenna elements.

  20. Design, simulation, evaluation, and technological verification of arrayed waveguide gratings

    NASA Astrophysics Data System (ADS)

    Seyringer, Dana; Schmid, Patrick; Bielik, Michal; Uherek, Frantisek; Chovan, Jozef; Kuzma, Anton

    2014-07-01

    We present the design, simulation, evaluation, and technological verification of various low-index optical demultiplexers based on arrayed waveguide gratings (AWGs). When designing such optical demultiplexers, a set of input geometrical parameters must be first calculated. They are essential to create AWG layout that will be then simulated using commercial photonics tools. However, these tools do not support or support only partially such a fundamental calculation. Therefore, a new stand-alone tool called AWG-Parameters was developed, which strongly reduces the time needed for the design. From the calculated geometrical parameters, the AWG layouts were created and simulated using three commercial photonic tools: Optiwave, (Ottawa, Ontario, Canada), Apollo Photonics, (Ancaster, Ontario, Canada), and R-Soft, (Pasadena, California). The designs were also technologically verified. The simulated/measured transmission characteristics were evaluated by our newly developed AWG-Analyzer tool. This tool provides calculations of AWG transmission parameters, which are also missing in commercial photonic tools. Additionally, the tool provides clear definitions of calculated transmission parameters together with their textual and graphical representations. Finally, the transmission characteristics and parameters achieved from different photonic tools were compared with each other and discussed in detail. The simulated results were also compared with the measurements. Very good agreement was achieved between theoretical (AWG-Parameters tool), simulated (commercial photonic tools), and fabricated AWG transmission parameters.

  1. Solar array technology evaluation program for SEPS (Solar Electrical Propulsion Stage)

    NASA Technical Reports Server (NTRS)

    1974-01-01

    An evaluation of the technology and the development of a preliminary design for a 25 kilowatt solar array system for solar electric propulsion are discussed. The solar array has a power to weight ratio of 65 watts per kilogram. The solar array system is composed of two wings. Each wing consists of a solar array blanket, a blanket launch storage container, an extension/retraction mast assembly, a blanket tensioning system, an array electrical harness, and hardware for supporting the system for launch and in the operating position. The technology evaluation was performed to assess the applicable solar array state-of-the-art and to define supporting research necessary to achieve technology readiness for meeting the solar electric propulsion system solar array design requirements.

  2. Activated chemoreceptor arrays remain intact and hexagonally packed

    PubMed Central

    Briegel, Ariane; Beeby, Morgan; Thanbichler, Martin; Jensen, Grant J.

    2013-01-01

    Summary Bacterial chemoreceptors cluster into exquisitively sensitive, tunable, highly ordered, polar arrays. While these arrays serve as paradigms of cell signalling in general, it remains unclear what conformational changes transduce signals from the periplasmic tips, where attractants and repellents bind, to the cytoplasmic signalling domains. Conflicting reports support and contest the hypothesis that activation causes large changes in the packing arrangement of the arrays, up to and including their complete disassembly. Using electron cryotomography, here we show that in Caulobacter crescentus, chemoreceptor arrays in cells grown in different media and immediately after exposure to the attractant galactose all exhibit the same 12 nm hexagonal packing arrangement, array size and other structural parameters. ΔcheB and ΔcheR mutants mimicking attractant- or repellent-bound states prior to adaptation also show the same lattice structure. We conclude that signal transduction and amplification must be accomplished through only small, nanoscale conformational changes. PMID:21992450

  3. Photovoltaic cell and array technology development for future unique NASA missions

    NASA Technical Reports Server (NTRS)

    Bailey, S.; Curtis, H.; Piszczor, M.; Surampudi, R.; Hamilton, T.; Rapp, D.; Stella, P.; Mardesich, N.; Mondt, J.; Bunker, R.; Nesmith, B.; Gaddy, E.; Marvin, D.; Kazmerski, L.

    2002-01-01

    A technology review committee from NASA, the U.S. Department of Energy (DOE), and the Air Force Research Lab, was formed to assess solar cell and array technologies required for future NASA science missions.

  4. Active pixel sensor array with multiresolution readout

    NASA Technical Reports Server (NTRS)

    Fossum, Eric R. (Inventor); Kemeny, Sabrina E. (Inventor); Pain, Bedabrata (Inventor)

    1999-01-01

    An imaging device formed as a monolithic complementary metal oxide semiconductor integrated circuit in an industry standard complementary metal oxide semiconductor process, the integrated circuit including a focal plane array of pixel cells, each one of the cells including a photogate overlying the substrate for accumulating photo-generated charge in an underlying portion of the substrate and a charge coupled device section formed on the substrate adjacent the photogate having a sensing node and at least one charge coupled device stage for transferring charge from the underlying portion of the substrate to the sensing node. There is also a readout circuit, part of which can be disposed at the bottom of each column of cells and be common to all the cells in the column. The imaging device can also include an electronic shutter formed on the substrate adjacent the photogate, and/or a storage section to allow for simultaneous integration. In addition, the imaging device can include a multiresolution imaging circuit to provide images of varying resolution. The multiresolution circuit could also be employed in an array where the photosensitive portion of each pixel cell is a photodiode. This latter embodiment could further be modified to facilitate low light imaging.

  5. DEVELOPMENT OF TECHNOLOGY TO REMOTELY NAVIGATE VERTICAL PIPE ARRAYS

    SciTech Connect

    Krementz, D.; Immel, D.; Vrettos, N.; Nance, T.; Marzolf, A.

    2011-07-01

    Situations exist around the Savannah River Site (SRS) and the Department of Energy (DOE) complex where it is advantageous to remotely navigate vertical pipe arrays. Specific examples are waste tanks in the SRS Tank Farms, which contain horizontal cooling coils at the tank bottom, vertical cooling coils throughout and a limited number of access points or ''risers''. These factors limit accessibility to many parts of these tanks by conventional means. Pipe Traveler technology has been developed to address these issues. The Pipe Traveler addresses these issues by using the vertical cooling coils as its medium of travel. The unit operates by grabbing a pipe using dual grippers located on either side of the equipment. Once securely attached to the pipe a drive wheel is extended to come in contact with the pipe. Rotation of the drive wheel causes the unit to rotate around the pipe. This action is continued until the second set of grippers is aligned with the next pipe. Extension pistons are actuated to extend the second set of grippers in contact with a second pipe. The second set of grippers is then actuated to grasp the pipe. The first set of grippers releases the original pipe and the process is repeated until the unit reaches its desired location. Once at the tool deployment location the desired tool may be used. The current design has proven the concept of pipe-to-pipe navigation. Testing of the Pipe Traveler has proven its ability to transfer itself from one pipe to another.

  6. Development and final design of FAME active array

    NASA Astrophysics Data System (ADS)

    Farkas, Szigfrid; Agócs, Tibor; Aitink-Kroes, Gabby; Bettonvil, Felix; Black, Martin; Hugot, Emmanuel; Jaskó, Attila; Miller, Chris; Schnetler, Hermine; van Duffelen, Farian; Venema, Lars

    2016-07-01

    FAME (Freeform Active Mirror Experiment - part of the FP7 OPTICON/FP7 development programme) intends to demonstrate the huge potential of active mirrors and freeform optical surfaces. Freeform active surfaces can help to address the new challenges of next generation astronomical instruments, which are bigger, more complex and have tighter specifications than their predecessors. The FAME design consists of a pre-formed, deformable thin mirror sheet with an active support system. The thin face sheet provides a close to final surface shape with very high surface quality. The active array provides the support, and through actuation, the control to achieve final surface shape accuracy. In this paper the development path, trade-offs and demonstrator design of the FAME active array is presented. The key step in the development process of the active array is the design of the mechanical structure and especially the optimization of the actuation node positions, where the actuator force is transmitted to the thin mirror sheet. This is crucial for the final performance of the mirror where the aim is to achieve an accurate surface shape, with low residual (high order) errors using the minimum number of actuators. These activities are based on the coupling of optical and mechanical engineering, using analytical and numerical methods, which results in an active array with optimized node positions and surface shape.

  7. Investigating brain functional evolution and plasticity using microelectrode array technology.

    PubMed

    Napoli, Alessandro; Obeid, Iyad

    2015-10-01

    The aim of this work was to investigate long and short-term plasticity responsible for memory formation in dissociated neuronal networks. In order to address this issue, a set of experiments was designed and implemented in which the microelectrode array electrode grid was divided into four quadrants, two of which were chronically stimulated, every two days for one hour with a stimulation paradigm that varied over time. Overall network and quadrant responses were then analyzed to quantify what level of plasticity took place in the network and how this was due to the stimulation interruption. The results demonstrate that there were no spatial differences in the stimulus-evoked activity within quadrants. Furthermore, the implemented stimulation protocol induced depression effects in the neuronal networks as demonstrated by the consistently lower network activity following stimulation sessions. Finally, the analysis demonstrated that the inhibitory effects of the stimulation decreased over time, thus suggesting a habituation phenomenon. These findings are sufficient to conclude that electrical stimulation is an important tool to interact with dissociated neuronal cultures, but localized stimuli are not enough to drive spatial synaptic potentiation or depression. On the contrary, the ability to modulate synaptic temporal plasticity was a feasible task to achieve by chronic network stimulation.

  8. Phased array-fed antenna configuration study: Technology assessment

    NASA Technical Reports Server (NTRS)

    Croswell, W. F.; Ball, D. E.; Taylor, R. C.

    1983-01-01

    Spacecraft array fed reflector antenna systems were assessed for particular application to a multiple fixed spot beam/multiple scanning spot beam system. Reflector optics systems are reviewed in addition to an investigation of the feasibility of the use of monolithic microwave integrated circuit power amplifiers and phase shifters in each element of the array feed.

  9. Vehicle Technologies Program Educational Activities

    SciTech Connect

    2011-12-13

    Description of educational activities including: EcoCAR2: Plugging In to the Future, EcoCAR: The NeXt Challenge, Green Racing, Automotive X Prize, Graduate Technology Automotive Education (GATE), and Hydrogen Education.

  10. Compensated individually addressable array technology for human breast imaging

    DOEpatents

    Lewis, D. Kent

    2003-01-01

    A method of forming broad bandwidth acoustic or microwave beams which encompass array design, array excitation, source signal preprocessing, and received signal postprocessing. This technique uses several different methods to achieve improvement over conventional array systems. These methods are: 1) individually addressable array elements; 2) digital-to-analog converters for the source signals; 3) inverse filtering from source precompensation; and 4) spectral extrapolation to expand the bandwidth of the received signals. The components of the system will be used as follows: 1) The individually addressable array allows scanning around and over an object, such as a human breast, without any moving parts. The elements of the array are broad bandwidth elements and efficient radiators, as well as detectors. 2) Digital-to-analog converters as the source signal generators allow virtually any radiated field to be created in the half-space in front of the array. 3) Preprocessing allows for corrections in the system, most notably in the response of the individual elements and in the ability to increase contrast and resolution of signal propagating through the medium under investigation. 4) Postprocessing allows the received broad bandwidth signals to be expanded in a process similar to analytic continuation. Used together, the system allows for compensation to create beams of any desired shape, control the wave fields generated to correct for medium differences, and improve contract and resolution in and through the medium.

  11. Space Photovoltaic Research and Technology, 1988. High Efficiency, Space Environment, and Array Technology

    NASA Technical Reports Server (NTRS)

    1989-01-01

    The 9th Space Photovoltaic Research and Technology conference was held at the NASA Lewis Research Center from April 19 to 21, 1988. The papers and workshop summaries report remarkable progress on a wide variety of approaches in space photovoltaics, for both near and far term applications. Among the former is the recently developed high efficiency GaAs/Ge cell, which formed the focus of a workshop discussion on heteroepitaxial cells. Still aimed at the long term, but with a significant payoff in a new mission capability, are InP cells, with their potentially dramatic improvement in radiation resistance. Approaches to near term, array specific powers exceeding 130 W/kg are also reported, and advanced concentrator panel technology with the potential to achieve over 250 W/sq m is beginning to take shape.

  12. Development of impedance matching technologies for ICRF antenna arrays

    SciTech Connect

    Pinsker, R.I.

    1998-03-01

    All high power ICRF heating systems include devices for matching the input impedance of the antenna array to the generator output impedance. For most types of antennas used, the input impedance is strongly time-dependent on timescales as rapid as 10-4 s, while the rf generators used are capable of producing full power only into a stationary load impedance. Hence, the dynamic response of the matching method is of great practical importance. In this paper, world-wide developments in this field over the past decade are reviewed. These techniques may be divided into several classes. The edge plasma parameters that determine the antenna array`s input impedance may be controlled to maintain a fixed load impedance. The frequency of the rf source can be feedback controlled to compensate for changes in the edge plasma conditions, or fast variable tuning elements in the transmission line between the generator output and the antenna input connections can provide the necessary time-varying impedance transformation. In lossy passive schemes, reflected power due to the time-varying impedance of the antenna array is diverted to a dummy load. Each of these techniques can be applied to a pre-existing antenna system. If a new antenna is to be designed, recent advances allow the antenna array to have the intrinsic property of presenting a constant load to the feeding transmission lines despite the varying load seen by each antenna in the array.

  13. Active pixel sensor array with electronic shuttering

    NASA Technical Reports Server (NTRS)

    Fossum, Eric R. (Inventor)

    2002-01-01

    An active pixel cell includes electronic shuttering capability. The cell can be shuttered to prevent additional charge accumulation. One mode transfers the current charge to a storage node that is blocked against accumulation of optical radiation. The charge is sampled from a floating node. Since the charge is stored, the node can be sampled at the beginning and the end of every cycle. Another aspect allows charge to spill out of the well whenever the charge amount gets higher than some amount, thereby providing anti blooming.

  14. Development of impedance matching technologies for ICRF antenna arrays

    NASA Astrophysics Data System (ADS)

    Pinsker, R. I.

    1998-08-01

    All high-power ion cyclotron range of frequency (ICRF) heating systems include devices for matching the input impedance of the antenna array to the generator output impedance. For most types of antennas used, the input impedance is strongly time dependent on timescales as rapid as 10-4 s, while the radio frequency (RF) generators used are capable of producing full power only into a stationary load impedance. Hence, the dynamic response of the matching method is of great practical importance. In this paper, world-wide developments in this field over the past decade are reviewed. These techniques may be divided into several classes. The edge plasma parameters that determine the antenna array's input impedance may be controlled to maintain a fixed load impedance. The frequency of the RF source can be feedback controlled to compensate for changes in the edge plasma conditions, or fast variable tuning elements in the transmission line between the generator output and the antenna input connections can provide the necessary time-varying impedance transformation. In `lossy passive schemes', reflected power due to the time-varying impedance of the antenna array is diverted to a dummy load. Each of these techniques can be applied to a pre-existing antenna system. If a new antenna is to be designed, recent advances allow the antenna array to have the intrinsic property of presenting a constant load to the feeding transmission lines despite the varying load seen by each antenna in the array.

  15. Interconnnect and bonding technologies for large flexible solar arrays

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Thermocompression bonding and conductive adhesive bonding are developed and evaluated as alternate methods of joining solar cells to their interconnect assemblies. Bonding materials and process controls applicable to fabrication of large, flexible substrate solar cell arrays are studied. The primary potential use of the techniques developed is on the solar array developed by NASA/MSFC and LMSC for solar electric propulsion (SEP) and shuttle payload applications. This array is made up of flexible panels approximately 0.7 by 3.4 meters. It is required to operate in space between 0.3 and 6 AU for 5 years with limited degradation. Materials selected must be capable of enduring this space environment, including outgassing and radiation.

  16. Acoustic Source Localization in Aircraft Interiors Using Microphone Array Technologies

    NASA Technical Reports Server (NTRS)

    Sklanka, Bernard J.; Tuss, Joel R.; Buehrle, Ralph D.; Klos, Jacob; Williams, Earl G.; Valdivia, Nicolas

    2006-01-01

    Using three microphone array configurations at two aircraft body stations on a Boeing 777-300ER flight test, the acoustic radiation characteristics of the sidewall and outboard floor system are investigated by experimental measurement. Analysis of the experimental data is performed using sound intensity calculations for closely spaced microphones, PATCH Inverse Boundary Element Nearfield Acoustic Holography, and Spherical Nearfield Acoustic Holography. Each method is compared assessing strengths and weaknesses, evaluating source identification capability for both broadband and narrowband sources, evaluating sources during transient and steady-state conditions, and quantifying field reconstruction continuity using multiple array positions.

  17. Infrared technology for satellite power conversion. [antenna arrays and bolometers

    NASA Technical Reports Server (NTRS)

    Campbell, D. P.; Gouker, M. A.; Gallagher, J. J.

    1984-01-01

    Successful fabrication of bismuth bolometers led to the observation of antenna action rom array elements. Fabrication of the best antennas arrays was made more facile with finding that increased argon flow during the dc sputtering produced more uniform bismuth films and bonding to antennas must be done with the substrate temperaure below 100 C. Higher temperatures damaged the bolometers. During the testing of the antennas, it was found that the use of a quasi-optical system provided a uniform radiation field. Groups of antennas were bonded in series and in parallel with the parallel configuration showing the greater response.

  18. Optically controlled phased-array technology for space communication systems

    NASA Technical Reports Server (NTRS)

    Kunath, Richard R.; Bhasin, Kul B.

    1988-01-01

    Using MMICs in phased-array applications above 20 GHz requires complex RF and control signal distribution systems. Conventional waveguide, coaxial cable, and microstrip methods are undesirable due to their high weight, high loss, limited mechanical flexibility and large volume. An attractive alternative to these transmission media, for RF and control signal distribution in MMIC phased-array antennas, is optical fiber. Presented are potential system architectures and their associated characteristics. The status of high frequency opto-electronic components needed to realize the potential system architectures is also discussed. It is concluded that an optical fiber network will reduce weight and complexity, and increase reliability and performance, but may require higher power.

  19. Noncontact Microembossing Technology for Fabricating Thermoplastic Optical Polymer Microlens Array Sheets

    PubMed Central

    Chang, Xuefeng; Ge, Xiaohong; Li, Hui

    2014-01-01

    Thermoplastic optical polymers have replaced traditional optical glass for many applications, due to their superior optical performance, mechanical characteristics, low cost, and efficient production process. This paper investigates noncontact microembossing technology used for producing microlens arrays made out of PMMA (polymethyl methacrylate), PS (polyStyrene), and PC (polycarbonate) from a quartz mold, with microhole arrays. An array of planoconvex microlenses are formed because of surface tension caused by applying pressure to the edge of a hole at a certain glass transition temperature. We studied the principle of noncontact microembossing techniques using finite element analysis, in addition to the thermal and mechanical properties of the three polymers. Then, the independently developed hot-embossing equipment was used to fabricate microlens arrays on PMMA, PS, and PC sheets. This is a promising technique for fabricating diverse thermoplastic optical polymer microlens array sheets, with a simple technological process and low production costs. PMID:25162063

  20. High-power semiconductor laser array packaged on microchannel cooler using gold-tin soldering technology

    NASA Astrophysics Data System (ADS)

    Wang, Jingwei; Kang, Lijun; Zhang, Pu; Nie, Zhiqiang; Li, Xiaoning; Xiong, Lingling; Liu, Xingsheng

    2012-03-01

    High power semiconductor laser arrays have found increased applications in many fields. In this work, a hard soldering microchannel cooler (HSMCC) technology was developed for packaging high power diode laser array. Numerical simulations of the thermal behavior characteristics of hard solder and indium solder MCC-packaged diode lasers were conducted and analyzed. Based on the simulated results, a series of high power HSMCC packaged diode laser arrays were fabricated and characterized. The test and statistical results indicated that under the same output power the HSMCC packaged laser bar has lower smile and high reliability in comparison with the conventional copper MCC packaged laser bar using indium soldering technology.

  1. Area Array Technology Evaluations for Space and Military Applications

    NASA Technical Reports Server (NTRS)

    Ghaffarian, Reza

    1996-01-01

    The Jet Propulsion Laboratory (JPL) is currently assessing the use of Area Array Packaging (AAP) for National Aeronautics and Space Administration (NASA) spaceflight applications. this work is being funded through NASA Headquarters, Code Q. The paper discusses background of AAP, objectives, and uses of AAP.

  2. Brain Activities and Educational Technology

    ERIC Educational Resources Information Center

    Riza, Emel

    2002-01-01

    There are close relationships between brain activities and educational technology. Brain is very important and so complicated part in our bodies. From long time scientists pay attention to that part and did many experiments, but they just reached little information like a drop in the sea. However from time to time they gave us some light to…

  3. Multi-electrode array technologies for neuroscience and cardiology

    NASA Astrophysics Data System (ADS)

    Spira, Micha E.; Hai, Aviad

    2013-02-01

    At present, the prime methodology for studying neuronal circuit-connectivity, physiology and pathology under in vitro or in vivo conditions is by using substrate-integrated microelectrode arrays. Although this methodology permits simultaneous, cell-non-invasive, long-term recordings of extracellular field potentials generated by action potentials, it is 'blind' to subthreshold synaptic potentials generated by single cells. On the other hand, intracellular recordings of the full electrophysiological repertoire (subthreshold synaptic potentials, membrane oscillations and action potentials) are, at present, obtained only by sharp or patch microelectrodes. These, however, are limited to single cells at a time and for short durations. Recently a number of laboratories began to merge the advantages of extracellular microelectrode arrays and intracellular microelectrodes. This Review describes the novel approaches, identifying their strengths and limitations from the point of view of the end users -- with the intention to help steer the bioengineering efforts towards the needs of brain-circuit research.

  4. Microwave beamed power technology improvement. [magnetrons and slotted waveguide arrays

    NASA Technical Reports Server (NTRS)

    Brown, W. C.

    1980-01-01

    The magnetron directional amplifier was tested for (1) phase shift and power output as a function of gain, anode current, and anode voltage, (2) background noise and harmonics in the output, (3) long life potential of the magnetron cathode, and (4) high operational efficiency. Examples of results were an adequate range of current and voltage over which 20 dB of amplification could be obtained, spectral noise density 155 dB below the carrier, 81.7% overall efficiency, and potential cathode life of 50 years in a design for solar power satellite use. A fabrication method was used to fabricate a 64 slot, 30 in square slotted waveguide array module from 0.020 in thick aluminum sheet. The test results on the array are discussed.

  5. Spherical loudspeaker array for local active control of sound.

    PubMed

    Rafaely, Boaz

    2009-05-01

    Active control of sound has been employed to reduce noise levels around listeners' head using destructive interference from noise-canceling sound sources. Recently, spherical loudspeaker arrays have been studied as multiple-channel sound sources, capable of generating sound fields with high complexity. In this paper, the potential use of a spherical loudspeaker array for local active control of sound is investigated. A theoretical analysis of the primary and secondary sound fields around a spherical sound source reveals that the natural quiet zones for the spherical source have a shell-shape. Using numerical optimization, quiet zones with other shapes are designed, showing potential for quiet zones with extents that are significantly larger than the well-known limit of a tenth of a wavelength for monopole sources. The paper presents several simulation examples showing quiet zones in various configurations.

  6. Inflatable Torus Solar Array Technology Program. Phase 1

    DTIC Science & Technology

    1991-10-15

    outgassing requirements as detailed in SP-R- 0022 and ASTM E595 and provides an effective barrier against atomic oxygen. The coating is currently...ABBREVIATIONS AMO - Air Mass 0 AO - Atomic Oxygen APSA - Advanced Photovoltaic Solar Array AR - Anti Reflective ASTM - American Society for Testing Materials...compares the initial tear strength of various 3 mil aluminum foils, measured by ASTM D1004 test method. The buckling strength of these tubes was measured on

  7. Atomic Layer Deposition Enabled Interconnect Technology for Vertical Nanowire Arrays

    DTIC Science & Technology

    2009-06-01

    nanowire light emitting diodes ( LEDs ), nanowire-based field effect transistors (FETs), resonators, batteries or biomedical applications. Keywords...vertical nanowire arrays are the best configuration for solid state super-capacitors [11,12], lithium ion batteries [13] and NW- LEDs [14],. These...electrodes are formed on top and bottom of NWs. For vertical NW-based LEDs , FETs or batteries, device performance could be significantly enhanced

  8. Inflatable TORUS Solar Array Technology Program. Phase 2.

    DTIC Science & Technology

    1994-01-01

    95 ° C, after pyroshock * and launch vibration environments z Figure 2. The ITSAT qualification array - deployed. Pyroshock was applied to the...development unit by the cable cutters which were installed on the housing. These self-induced pyroshock environments were also applied to the qualification...maximum diameter of 46 in. The payload envelope is shown in Figure 5. The packaged canister has been designed to the worst-case vibration, pyroshock , and

  9. Large-Aperture Membrane Active Phased-Array Antennas

    NASA Technical Reports Server (NTRS)

    Karasik, Boris; McGrath, William; Leduc, Henry

    2009-01-01

    Large-aperture phased-array microwave antennas supported by membranes are being developed for use in spaceborne interferometric synthetic aperture radar systems. There may also be terrestrial uses for such antennas supported on stationary membranes, large balloons, and blimps. These antennas are expected to have areal mass densities of about 2 kg/sq m, satisfying a need for lightweight alternatives to conventional rigid phased-array antennas, which have typical areal mass densities between 8 and 15 kg/sq m. The differences in areal mass densities translate to substantial differences in total mass in contemplated applications involving aperture areas as large as 400 sq m. A membrane phased-array antenna includes patch antenna elements in a repeating pattern. All previously reported membrane antennas were passive antennas; this is the first active membrane antenna that includes transmitting/receiving (T/R) electronic circuits as integral parts. Other integral parts of the antenna include a network of radio-frequency (RF) feed lines (more specifically, a corporate feed network) and of bias and control lines, all in the form of flexible copper strip conductors on flexible polymeric membranes. Each unit cell of a prototype antenna (see Figure 1) contains a patch antenna element and a compact T/R module that is compatible with flexible membrane circuitry. There are two membrane layers separated by a 12.7-mm air gap. Each membrane layer is made from a commercially available flexible circuit material that, as supplied, comprises a 127-micron-thick polyimide dielectric layer clad on both sides with 17.5-micron-thick copper layers. The copper layers are patterned into RF, bias, and control conductors. The T/R module is located on the back side of the ground plane and is RF-coupled to the patch element via a slot. The T/R module is a hybrid multilayer module assembled and packaged independently and attached to the membrane array. At the time of reporting the information for

  10. Ionospheric effects in active retrodirective array and mitigating system design

    NASA Technical Reports Server (NTRS)

    Nandi, A. K.; Tomita, C. Y.

    1980-01-01

    The operation of an active retrodirective array (ARA) in an ionospheric environment (that is either stationary or slowly-varying) was examined. The restrictions imposed on the pilot signal structure as a result of such operation were analyzed. A 3 tone pilot beam system was defined which first estimates the total electron content along paths of interest and then utilizes this information to aid the phase conjugator so that correct beam pointing can be achieved.

  11. Characteristics of Monolithically Integrated InGaAs Active Pixel Imager Array

    NASA Technical Reports Server (NTRS)

    Kim, Q.; Cunningham, T. J.; Pain, B.; Lange, M. J.; Olsen, G. H.

    2000-01-01

    Switching and amplifying characteristics of a newly developed monolithic InGaAs Active Pixel Imager Array are presented. The sensor array is fabricated from InGaAs material epitaxially deposited on an InP substrate. It consists of an InGaAs photodiode connected to InP depletion-mode junction field effect transistors (JFETs) for low leakage, low power, and fast control of circuit signal amplifying, buffering, selection, and reset. This monolithically integrated active pixel sensor configuration eliminates the need for hybridization with silicon multiplexer. In addition, the configuration allows the sensor to be front illuminated, making it sensitive to visible as well as near infrared signal radiation. Adapting the existing 1.55 micrometer fiber optical communication technology, this integration will be an ideal system of optoelectronic integration for dual band (Visible/IR) applications near room temperature, for use in atmospheric gas sensing in space, and for target identification on earth. In this paper, two different types of small 4 x 1 test arrays will be described. The effectiveness of switching and amplifying circuits will be discussed in terms of circuit effectiveness (leakage, operating frequency, and temperature) in preparation for the second phase demonstration of integrated, two-dimensional monolithic InGaAs active pixel sensor arrays for applications in transportable shipboard surveillance, night vision, and emission spectroscopy.

  12. Technology for Solar Array Production on the Moon

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.

    2002-01-01

    Silicon, aluminum, and glass are the primary raw materials that will be required for production of solar arrays on the moon. A process sequence is proposed for producing these materials from lunar regolith is proposed, consisting of separating the required materials from lunar rock with fluorine. Fluorosilane produced by this process is reduced to silicon; the fluorine salts are reduced to metals by reaction with metallic potassium. Fluorine is recovered from residual MgF and CaF2 by reaction with K2O. Aluminum, calcium oxide, and magnesium oxide are recovered to manufacture structural materials and glass.

  13. Aperiodic arrays of active nanopillars for radiation engineering

    NASA Astrophysics Data System (ADS)

    Lawrence, Nate; Trevino, Jacob; Dal Negro, Luca

    2012-06-01

    We engineer aperiodic nanostructures for enhanced omnidirectional light extraction and coupling of 1.55 μm radiation to distinctive optical resonances carrying of orbital angular momentum (OAM) using light emitting Si-based materials. By systematically studying nanopillar arrays with varying pillar separations and increasing degree of rotational symmetry in Fourier space, we show that omnidirectional extraction is achieved with circularly symmetric Fourier space, leading to best light emission enhancement from planar devices such as LEDs or lasers. To demonstrate the potential of active aperiodic structures with azimuthally isotropic k-space, we fabricate nanopillar arrays of erbium doped silicon-rich nitride using electron beam lithography and reactive ion etching. Experimental results obtained using leaky-mode photoluminescence spectroscopy prove over 10 times extraction enhancement at 1.55 μm from aperiodic golden angle spirals (GA spirals), in good agreement with design based on analytical Bragg scattering and finite difference time domain calculations. In addition, by imaging Er radiation in direct and reciprocal space, we demonstrate that GA spiral arrays support angularly isotropic emission patterns and distinctive optical resonances with a well-defined azimuthal structure carrying OAM. These findings offer unique opportunities for the engineering of novel active structures that leverage isotropic emission patterns and structured light for secure optical communication, sensing, imaging, and light sources on a Si platform.

  14. Digital Tracking Array for FM Signals Based on Off-The-Shelf Wireless Technologies

    DTIC Science & Technology

    2007-12-01

    platforms as antenna elements of the array, like a microstrip patch antenna , can conform to the structure of stealthy platforms. Its agile scanning rate... antenna architectures were studied and the requirements for hardware components such as the analog-to-digital converters and amplifiers are specified...15. NUMBER OF PAGES 101 14. SUBJECT TERMS Tracking,Array Antenna , Wireless Technologies,UAV, Sun and difference beams. 16. PRICE CODE 17

  15. Next Generation Large Mode Area Fiber Technologies for High Power Fiber Laser Arrays

    DTIC Science & Technology

    2012-06-08

    REPORT Next Generation Large Mode Area Fiber Technologies for High Power Fiber Laser Arrays 14. ABSTRACT 16. SECURITY CLASSIFICATION OF: This program...monolithically-integrated building blocks (individual laser channels) of high power beam-combined fiber laser arrays. Robust single-mode performance...of CCC fibers with core sizes of up to ~60?m has been rigorously demonstrated. Various CCC fiber based high power lasers have been also

  16. Active Antenna Development for the Long Wavelength Array

    NASA Astrophysics Data System (ADS)

    Stewart, K. P.; Hicks, B. C.; Crane, P. C.; Ray, P. S.; Gross, C.; Polisensky, E. J.; Erickson, W. C.

    2005-12-01

    We are developing and testing active baluns and electrically short dipoles for possible use as the primary wideband receiving elements in the Long Wavelength Array (LWA) for HF-VHF radio astronomy. Several dipoles of various designs and dimensions have been built and tested. Their useful range occurs when the dipole arms are approximately 1/8 to one wavelength long and the feedpoint is less than 1/2 wavelength above ground. An eight-element NRL LWA Test Array (NLTA) interferometer has been built and fringes have been observed from the brightest celestial sources in the frequency range from 10 MHz to 50 MHz. The antenna temperatures vary from about 10% to 100% of the average brightness temperature of the galactic background. With these parameters it is easy to make the amplifier noise levels low enough that final system temperature is dominated by the galactic background.

  17. Frequency translating phase conjugation circuit for active retrodirective antenna array

    NASA Astrophysics Data System (ADS)

    Chernoff, R.

    1980-11-01

    An active retrodirective antenna array which has central phasing from a reference antenna element through a "tree" structured network of transmission lines utilizes a number of phase conjugate circuits (PCCs) at each node and a phase reference regeneration circuit (PRR) at each node except the initial node. Each node virtually coincides with an element of the array. A PCC generates the exact conjugate phase of an incident signal using a phase locked loop which combines the phases in an up converter, divides the sum by 2 and mixes the result with the phase in a down converter for phase detection. The PRR extracts the phase from the conjugate phase. Both the PCC and the PRR are not only exact but also free from mixer degeneracy.

  18. Promising Results from Three NASA SBIR Solar Array Technology Development Programs

    NASA Technical Reports Server (NTRS)

    Eskenazi, Mike; White, Steve; Spence, Brian; Douglas, Mark; Glick, Mike; Pavlick, Ariel; Murphy, David; O'Neill, Mark; McDanal, A. J.; Piszczor, Michael

    2005-01-01

    Results from three NASA SBIR solar array technology programs are presented. The programs discussed are: 1) Thin Film Photovoltaic UltraFlex Solar Array; 2) Low Cost/Mass Electrostatically Clean Solar Array (ESCA); and 3) Stretched Lens Array SquareRigger (SLASR). The purpose of the Thin Film UltraFlex (TFUF) Program is to mature and validate the use of advanced flexible thin film photovoltaics blankets as the electrical subsystem element within an UltraFlex solar array structural system. In this program operational prototype flexible array segments, using United Solar amorphous silicon cells, are being manufactured and tested for the flight qualified UltraFlex structure. In addition, large size (e.g. 10 kW GEO) TFUF wing systems are being designed and analyzed. Thermal cycle and electrical test and analysis results from the TFUF program are presented. The purpose of the second program entitled, Low Cost/Mass Electrostatically Clean Solar Array (ESCA) System, is to develop an Electrostatically Clean Solar Array meeting NASA s design requirements and ready this technology for commercialization and use on the NASA MMS and GED missions. The ESCA designs developed use flight proven materials and processes to create a ESCA system that yields low cost, low mass, high reliability, high power density, and is adaptable to any cell type and coverglass thickness. All program objectives, which included developing specifications, creating ESCA concepts, concept analysis and trade studies, producing detailed designs of the most promising ESCA treatments, manufacturing ESCA demonstration panels, and LEO (2,000 cycles) and GEO (1,350 cycles) thermal cycling testing of the down-selected designs were successfully achieved. The purpose of the third program entitled, "High Power Platform for the Stretched Lens Array," is to develop an extremely lightweight, high efficiency, high power, high voltage, and low stowed volume solar array suitable for very high power (multi-kW to MW

  19. The impact of solar cell technology on planar solar array performance

    NASA Technical Reports Server (NTRS)

    Mills, Michael W.; Kurland, Richard M.

    1989-01-01

    The results of a study into the potential impact of advanced solar cell technologies on the characteristics (weight, cost, area) of typical planar solar arrays designed for low, medium and geosynchronous altitude earth orbits are discussed. The study considered planar solar array substrate designs of lightweight, rigid-panel graphite epoxy and ultra-lightweight Kapton. The study proposed to answer the following questions: Do improved cell characteristics translate into array-level weight, size and cost improvements; What is the relative importance of cell efficiency, weight and cost with respect to array-level performance; How does mission orbital environment affect array-level performance. Comparisons were made at the array level including all mechanisms, hinges, booms, and harnesses. Array designs were sized to provide 5kW of array power (not spacecraft bus power, which is system dependent but can be scaled from given values). The study used important grass roots issues such as use of the GaAs radiation damage coefficients as determined by Anspaugh. Detailed costing was prepared, including cell and cover costs, and manufacturing attrition rates for the various cell types.

  20. SCARLET I: Mechanization solutions for deployable concentrator optics integrated with rigid array technology

    NASA Technical Reports Server (NTRS)

    Wachholz, James J.; Murphy, David M.

    1996-01-01

    The SCARLET I (Solar Concentrator Army with Refractive Linear Element Technology) solar array wing was designed and built to demonstrate, in flight, the feasibility of integrating deployable concentrator optics within the design envelope of typical rigid array technology. Innovative mechanism designs were used throughout the array, and a full series of qualification tests were successfully performed in anticipation of a flight on the Multiple Experiment Transporter to Earth Orbit and Return (METEOR) spacecraft. Even though the Conestoga launch vehicle was unable to place the spacecraft in orbit, the program effort was successful in achieving the milestones of analytical and design development functional validation, and flight qualification, thus leading to a future flight evaluation for the SCARLET technology.

  1. SCARLET I: Mechanization solutions for deployable concentrator optics integrated with rigid array technology

    SciTech Connect

    Wachholz, J.J.; Murphy, D.M.

    1996-05-01

    The SCARLET I (Solar Concentrator Army with Refractive Linear Element Technology) solar array wing was designed and built to demonstrate, in flight, the feasibility of integrating deployable concentrator optics within the design envelope of typical rigid array technology. Innovative mechanism designs were used throughout the array, and a full series of qualification tests were successfully performed in anticipation of a flight on the Multiple Experiment Transporter to Earth Orbit and Return (METEOR) spacecraft. Even though the Conestoga launch vehicle was unable to place the spacecraft in orbit, the program effort was successful in achieving the milestones of analytical and design development functional validation, and flight qualification, thus leading to a future flight evaluation for the SCARLET technology.

  2. Arrayed antibody library technology for therapeutic biologic discovery.

    PubMed

    Bentley, Cornelia A; Bazirgan, Omar A; Graziano, James J; Holmes, Evan M; Smider, Vaughn V

    2013-03-15

    Traditional immunization and display antibody discovery methods rely on competitive selection amongst a pool of antibodies to identify a lead. While this approach has led to many successful therapeutic antibodies, targets have been limited to proteins which are easily purified. In addition, selection driven discovery has produced a narrow range of antibody functionalities focused on high affinity antagonism. We review the current progress in developing arrayed protein libraries for screening-based, rather than selection-based, discovery. These single molecule per microtiter well libraries have been screened in multiplex formats against both purified antigens and directly against targets expressed on the cell surface. This facilitates the discovery of antibodies against therapeutically interesting targets (GPCRs, ion channels, and other multispanning membrane proteins) and epitopes that have been considered poorly accessible to conventional discovery methods.

  3. Space Power Amplification with Active Linearly Tapered Slot Antenna Array

    NASA Technical Reports Server (NTRS)

    Simons, Rainee N.; Lee, Richard Q.

    1993-01-01

    A space power amplifier composed of active linearly tapered slot antennas (LTSA's) has been demonstrated and shown to have a gain of 30 dB at 20 GHz. In each of the antenna elements, a GaAs monolithic microwave integrated circuit (MMIC) three-stage power amplifier is integrated with two LTSA's. The LTSA and the MMIC power amplifier has a gain of 11 dB and power added efficiency of 14 percent respectively. The design is suitable for constructing a large array using monolithic integration techniques.

  4. Spatial frequency multiplier with active linearly tapered slot antenna array

    NASA Technical Reports Server (NTRS)

    Simons, Rainee N.; Lee, Richard Q.

    1994-01-01

    A frequency multiplier with active linearly tapered slot antennas (LTSA's) has been demonstrated at the second harmonic frequency. In each antenna element, a GaAs monolithic microwave integrated circuit (MMIC) distributed amplifier is integrated with two LTSA's. The multiplier has a very wide bandwidth and large dynamic range. The fundamental-to-second harmonic conversion efficiency is 8.1 percent. The spatially combined second harmonic signal is 50 dB above the noise level. The design is suitable for constructing a large array using monolithic integration techniques.

  5. Multi-carrier mobile TDMA system with active array antenna

    NASA Technical Reports Server (NTRS)

    Suzuki, Ryutaro; Matsumoto, Yasushi; Hamamoto, Naokazu

    1990-01-01

    A multi-carrier time division multiple access (TDMA) is proposed for the future mobile satellite communications systems that include a multi-satellite system. This TDMA system employs the active array antenna in which the digital beam forming technique is adopted to control the antenna beam direction. The antenna beam forming is carried out at the base band frequency by using the digital signal processing technique. The time division duplex technique is applied for the TDM/TDMA burst format, in order not to overlap transmit and receive timing.

  6. Matrix phased array (MPA) imaging technology for resistance spot welds

    SciTech Connect

    Na, Jeong K.; Gleeson, Sean T.

    2014-02-18

    A three-dimensional MPA probe has been incorporated with a high speed phased array electronic board to visualize nugget images of resistance spot welds. The primary application area of this battery operated portable MPA ultrasonic imaging system is in the automotive industry which a conventional destructive testing process is commonly adopted to check the quality of resistance spot welds in auto bodies. Considering an average of five-thousand spot welds in a medium size passenger vehicle, the amount of time and effort given to popping the welds and measuring nugget size are immeasurable in addition to the millions of dollars' worth of scrap metals recycled per plant per year. This wasteful labor intensive destructive testing process has become less reliable as auto body sheet metal has transitioned from thick and heavy mild steels to thin and light high strength steels. Consequently, the necessity of developing a non-destructive inspection methodology has become inevitable. In this paper, the fundamental aspects of the current 3-D probe design, data acquisition algorithms, and weld nugget imaging process are discussed.

  7. Matrix phased array (MPA) imaging technology for resistance spot welds

    NASA Astrophysics Data System (ADS)

    Na, Jeong K.; Gleeson, Sean T.

    2014-02-01

    A three-dimensional MPA probe has been incorporated with a high speed phased array electronic board to visualize nugget images of resistance spot welds. The primary application area of this battery operated portable MPA ultrasonic imaging system is in the automotive industry which a conventional destructive testing process is commonly adopted to check the quality of resistance spot welds in auto bodies. Considering an average of five-thousand spot welds in a medium size passenger vehicle, the amount of time and effort given to popping the welds and measuring nugget size are immeasurable in addition to the millions of dollars' worth of scrap metals recycled per plant per year. This wasteful labor intensive destructive testing process has become less reliable as auto body sheet metal has transitioned from thick and heavy mild steels to thin and light high strength steels. Consequently, the necessity of developing a non-destructive inspection methodology has become inevitable. In this paper, the fundamental aspects of the current 3-D probe design, data acquisition algorithms, and weld nugget imaging process are discussed.

  8. The Square Kilometer Array: Key Science and Technology Development

    NASA Astrophysics Data System (ADS)

    Cordes, J. M.

    2005-12-01

    This paper summarizes the science goals for the Square Kilometer Array and its possible implementation. The SKA is the next generation radio telescope that will revolutionize our knowledge of the universe. The SKA will enable massive surveys of many kinds at meter and centimeter wavelengths. It is being designed to probe fundamental questions in physics, such as the nature of dark energy and dark matter and the properties of gravity in the strong-field limit. The SKA will also lead to a better understanding of complexity in the universe, viz. the origins of magnetic fields, galaxies, stars, planets and life. Currently the purpose and specifications of the SKA are defined in terms of five key science areas, which are summarized here, along with the enormous discovery space that will be opened up by the SKA. The key ``axes of discovery'' for the SKA include a huge boost in sensitivity combined with high angular resolution and wide field of view (FoV). These innovations, combined with those developed in radio astronomy contexts over the last few decades, will open new windows to the universe. It will also provide numerous synergistic studies with telescopes that span the electromagnetic spectrum as well as with non-electromagnetic telescopes, especially gravitational wave detectors.

  9. Analysis of mismatch and shading effects in a photovoltaic array using different technologies

    NASA Astrophysics Data System (ADS)

    Guerrero, J.; Muñoz, Y.; Ibáñez, F.; Ospino, A.

    2014-06-01

    In this paper, we analyze the performance of a photovoltaic array implemented in the Universidad Politécnica de Valencia which consists of modules of different technologies and power, connected in series, in order to quantify the energy losses due to mismatch and the effect of the shadows. To do this, the performance of the modules was measured in operation under ambient conditions with field measurement equipment (AMPROBE Solar Analyzer, Solar - 4000), which allows the extrapolation of measures to standard conditions STC. For the data validation, measures under controlled conditions were taken to some modules in the flash test laboratory of the Institute of Energy Technology ITE of Valencia in Spain. Subsequently the array curves measured were validated with a photovoltaic array model developed in MATLAB-Simulink for the same conditions and technologies. The results of this particular array are lost up to 20% of the energy supplied due to the modules mismatch. The study shows the curves and the energy loss due to shadows modules. This result opens scenarios for conceivable modifications to the PV field configurations today, chosen during the design stage and unchangeable during the operating stage; and gives greater importance to the energy loss by mismatch in the PV array.

  10. Characteristics of Monolithically Integrated InGaAs Active Pixel Image Array

    NASA Technical Reports Server (NTRS)

    Kim, Q.; Cunningham, T. J.; Pain, B.; Lange, M. J.; Olsen, G. H.

    1999-01-01

    Switching and amplifying characteristics of a newly developed monolithic InGaAs Active Pixel Imager Array are presented. The sensor array is fabricated from InGaAs material epitaxially deposited on an InP substrate.

  11. Active noise control using a steerable parametric array loudspeaker.

    PubMed

    Tanaka, Nobuo; Tanaka, Motoki

    2010-06-01

    Arguably active noise control enables the sound suppression at the designated control points, while the sound pressure except the targeted locations is likely to augment. The reason is clear; a control source normally radiates the sound omnidirectionally. To cope with this problem, this paper introduces a parametric array loudspeaker (PAL) which produces a spatially focused sound beam due to the attribute of ultrasound used for carrier waves, thereby allowing one to suppress the sound pressure at the designated point without causing spillover in the whole sound field. First the fundamental characteristics of PAL are overviewed. The scattered pressure in the near field contributed by source strength of PAL is then described, which is needed for the design of an active noise control system. Furthermore, the optimal control law for minimizing the sound pressure at control points is derived, the control effect being investigated analytically and experimentally. With a view to tracking a moving target point, a steerable PAL based upon a phased array scheme is presented, with the result that the generation of a moving zone of quiet becomes possible without mechanically rotating the PAL. An experiment is finally conducted, demonstrating the validity of the proposed method.

  12. Tribotronic Transistor Array as an Active Tactile Sensing System.

    PubMed

    Yang, Zhi Wei; Pang, Yaokun; Zhang, Limin; Lu, Cunxin; Chen, Jian; Zhou, Tao; Zhang, Chi; Wang, Zhong Lin

    2016-12-27

    Large-scale tactile sensor arrays are of great importance in flexible electronics, human-robot interaction, and medical monitoring. In this paper, a flexible 10 × 10 tribotronic transistor array (TTA) is developed as an active tactile sensing system by incorporating field-effect transistor units and triboelectric nanogenerators into a polyimide substrate. The drain-source current of each tribotronic transistor can be individually modulated by the corresponding external contact, which has induced a local electrostatic potential to act as the conventional gate voltage. By scaling down the pixel size from 5 × 5 to 0.5 × 0.5 mm(2), the sensitivities of single pixels are systematically investigated. The pixels of the TTA show excellent durability, independence, and synchronicity, which are suitable for applications in real-time tactile sensing, motion monitoring, and spatial mapping. The integrated tribotronics provides an unconventional route to realize an active tactile sensing system, with prospective applications in wearable electronics, human-machine interfaces, fingerprint identification, and so on.

  13. Performance Based Education. Technology Activity Modules.

    ERIC Educational Resources Information Center

    Custer, Rodney L., Ed.

    These Technology Activity Modules are designed to serve as an implementation resource for technology education teachers as they integrate technology education with Missouri's Academic Performance Standards and provide a source of activities and activity ideas that can be used to integrate and reinforce learning across the curriculum. The modules…

  14. Precision molding of advanced glass optics: innovative production technology for lens arrays and free form optics

    NASA Astrophysics Data System (ADS)

    Pongs, Guido; Bresseler, Bernd; Bergs, Thomas; Menke, Gert

    2012-10-01

    Today isothermal precision molding of imaging glass optics has become a widely applied and integrated production technology in the optical industry. Especially in consumer electronics (e.g. digital cameras, mobile phones, Blu-ray) a lot of optical systems contain rotationally symmetrical aspherical lenses produced by precision glass molding. But due to higher demands on complexity and miniaturization of optical elements the established process chain for precision glass molding is not sufficient enough. Wafer based molding processes for glass optics manufacturing become more and more interesting for mobile phone applications. Also cylindrical lens arrays can be used in high power laser systems. The usage of unsymmetrical free-form optics allows an increase of efficiency in optical laser systems. Aixtooling is working on different aspects in the fields of mold manufacturing technologies and molding processes for extremely high complex optical components. In terms of array molding technologies, Aixtooling has developed a manufacturing technology for the ultra-precision machining of carbide molds together with European partners. The development covers the machining of multi lens arrays as well as cylindrical lens arrays. The biggest challenge is the molding of complex free-form optics having no symmetrical axis. A comprehensive CAD/CAM data management along the entire process chain is essential to reach high accuracies on the molded lenses. Within a national funded project Aixtooling is working on a consistent data handling procedure in the process chain for precision molding of free-form optics.

  15. Diversity Arrays Technology (DArT) platform for genotyping and mapping in carrot (Daucus carota L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Carrot is one of the most important root vegetable crops grown worldwide on more than one million hectares. Its progenitor, wild Daucus carota, is a weed commonly occurring across continents in the temperate climatic zone. Diversity Array Technology (DArT) is a microarray-based molecular marker syst...

  16. High-throughput genotyping of hop (Humulus lupulus L.) utilising diversity arrays technology (DArT)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Implementation of molecular methods in hop breeding is dependent on the availability of sizeable numbers of polymorphic markers and a comprehensive understanding of genetic variation. Diversity Arrays Technology (DArT) is a high-throughput cost-effective method for the discovery of large numbers of...

  17. An array of microactuated microelectrodes for monitoring single-neuronal activity in rodents.

    PubMed

    Muthuswamy, Jit; Okandan, Murat; Gilletti, Aaron; Baker, Michael S; Jain, Tilak

    2005-08-01

    Arrays of microelectrodes used for monitoring single- and multi-neuronal action potentials often fail to record from the same population of neurons over a period of time for several technical and biological reasons. We report here a novel Neural Probe chip with a 3-channel microactuated microelectrode array that will enable precise repositioning of the individual microelectrodes within the brain tissue after implantation. Thermal microactuators and associated microelectrodes in the Neural Probe chip are microfabricated using the Sandia's Ultraplanar Multi-level MEMS Technology (SUMMiTV) process, a 5-layer polysilicon micromachining technology of the Sandia National labs, Albuquerque, NM. The Neural Probe chip enables precise bi-directional positioning of the microelectrodes in the brain with a step resolution in the order of 8.8 microm. The thermal microactuators allow for a linear translation of the microelectrodes of up to 5 mm in either direction making it suitable for positioning microelectrodes in deep structures of a rodent brain. The overall translation in either direction was reduced to approximately 2 mm after insulation of the microelectrodes with epoxy for monitoring multi-unit activity. Single unit recordings were obtained from the somatosensory cortex of adult rats over a period of three days demonstrating the feasibility of this technology. Further optimization of the microelectrode insulation and chip packaging will be necessary before this technology can be validated in chronic experiments.

  18. An Array of Microactuated Microelectrodes for Monitoring Single-Neuronal Activity in Rodents

    PubMed Central

    Okandan, Murat; Gilletti, Aaron; Baker, Michael S.; Jain, Tilak

    2006-01-01

    Arrays of microelectrodes used for monitoring single-and multi-neuronal action potentials often fail to record from the same population of neurons over a period of time for several technical and biological reasons. We report here a novel Neural Probe chip with a 3-channel microactuated microelectrode array that will enable precise repositioning of the individual microelectrodes within the brain tissue after implantation. Thermal microactuators and associated microelectrodes in the Neural Probe chip are microfabricated using the Sandia’s Ultraplanar Multi-level MEMS Technology (SUMMiTV) process, a 5-layer polysilicon microma-chining technology of the Sandia National labs, Albuquerque, NM. The Neural Probe chip enables precise bi-directional positioning of the microelectrodes in the brain with a step resolution in the order of 8.8μm. The thermal microactuators allow for a linear translation of the microelectrodes of up to 5 mm in either direction making it suitable for positioning microelectrodes in deep structures of a rodent brain. The overall translation in either direction was reduced to approximately 2 mm after insulation of the microelectrodes with epoxy for monitoring multi-unit activity. Single unit recordings were obtained from the somatosensory cortex of adult rats over a period of three days demonstrating the feasibility of this technology. Further optimization of the microelectrode insulation and chip packaging will be necessary before this technology can be validated in chronic experiments. PMID:16119243

  19. Active Travel-Time Tomography using a Distributed Acoustic Sensing Array

    NASA Astrophysics Data System (ADS)

    Lancelle, C.; Fratta, D.; Lord, N. E.; Wang, H. F.; Chalari, A.

    2015-12-01

    Distributed acoustic sensing (DAS) is a sensor array used for monitoring ground motion by utilizing the interaction of light pulses with sections of a fiber-optic cable. In September 2013 a field test was conducted at the NEES@UCSB Garner Valley field site in Southern California incorporating DAS technology. A 762-meter-long fiber-optic cable was trenched to a depth of about 0.3 m in a rectangular design with two interior diagonal segments. The fiber was excited by a number of sources, including a 45 kN shear shaker and a smaller 450 N portable mass shaker, both of which were available through NEES@UCLA. In addition to these sources, signals were recorded from a minivib source and hammer blows on a steel plate, as well as 8 hours of overnight ambient noise recording. One goal of the field test was to evaluate the use of DAS for tomographic studies. The large number of measurement points inherent to DAS lends itself well to this type of study. Tomograms were constructed using two of the active-sources at multiple locations. There were 8 minivib locations within the array and 13 hammer locations along the boundary of the array. Travel-time data were collected with the DAS array. Two-dimensional velocity tomograms were constructed for different resolutions from the two active sources and compared. In all the images, the lowest velocities lie near the center of the array with higher velocities surrounding this area. The impact results, however, may contain an artifact due to multiple propagation modes. This research is part of the DOE's PoroTomo project.

  20. Bend, stretch, and touch: Locating a finger on an actively deformed transparent sensor array

    PubMed Central

    Sarwar, Mirza Saquib; Dobashi, Yuta; Preston, Claire; Wyss, Justin K. M.; Mirabbasi, Shahriar; Madden, John David Wyndham

    2017-01-01

    The development of bendable, stretchable, and transparent touch sensors is an emerging technological goal in a variety of fields, including electronic skin, wearables, and flexible handheld devices. Although transparent tactile sensors based on metal mesh, carbon nanotubes, and silver nanowires demonstrate operation in bent configurations, we present a technology that extends the operation modes to the sensing of finger proximity including light touch during active bending and even stretching. This is accomplished using stretchable and ionically conductive hydrogel electrodes, which project electric field above the sensor to couple with and sense a finger. The polyacrylamide electrodes are embedded in silicone. These two widely available, low-cost, transparent materials are combined in a three-step manufacturing technique that is amenable to large-area fabrication. The approach is demonstrated using a proof-of-concept 4 × 4 cross-grid sensor array with a 5-mm pitch. The approach of a finger hovering a few centimeters above the array is readily detectable. Light touch produces a localized decrease in capacitance of 15%. The movement of a finger can be followed across the array, and the location of multiple fingers can be detected. Touch is detectable during bending and stretch, an important feature of any wearable device. The capacitive sensor design can be made more or less sensitive to bending by shifting it relative to the neutral axis. Ultimately, the approach is adaptable to the detection of proximity, touch, pressure, and even the conformation of the sensor surface. PMID:28345045

  1. Human Islets Exhibit Electrical Activity on Microelectrode Arrays (MEA).

    PubMed

    Schönecker, S; Kraushaar, U; Guenther, E; Gerst, F; Ullrich, S; Häring, H-U; Königsrainer, A; Barthlen, W; Drews, G; Krippeit-Drews, P

    2015-05-01

    This study demonstrates for the first time that the microelectrode array (MEA) technique allows analysis of electrical activity of islets isolated from human biopsies. We have shown before that this method, i.e., measuring beta cell electrical activity with extracellular electrodes, is a powerful tool to assess glucose responsiveness of isolated murine islets. In the present study, human islets were shown to exhibit glucose-dependent oscillatory electrical activity. The glucose responsiveness could be furthermore demonstrated by an increase of insulin secretion in response to glucose. Electrical activity was increased by tolbutamide and inhibited by diazoxide. In human islets bursts of electrical activity were markedly blunted by the Na(+) channel inhibitor tetrodotoxin which does not affect electrical activity in mouse islets. Thus, the MEA technique emerges as a powerful tool to decipher online the unique features of human islets.Additionally, this technique will enable research with human islets even if only a few islets are available and it will allow a fast and easy test of metabolic integrity of islets destined for transplantation.

  2. Health Occupations. Technology Learning Activity. Teacher Edition. Technology Education Series.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This packet of technology learning activity (TLA) materials on health occupations for students in grades 6-10 consists of a technology education overview, information on use, and instructor's and student's sections. The overview discusses the technology education program and materials. Components of the instructor's and student's sections are…

  3. A monolithic array of three-dimensional ion traps fabricated with conventional semiconductor technology.

    PubMed

    Wilpers, Guido; See, Patrick; Gill, Patrick; Sinclair, Alastair G

    2012-09-01

    The coherent control of quantum-entangled states of trapped ions has led to significant advances in quantum information, quantum simulation, quantum metrology and laboratory tests of quantum mechanics and relativity. All of the basic requirements for processing quantum information with arrays of ion-based quantum bits (qubits) have been proven in principle. However, so far, no more than 14 ion-based qubits have been entangled with the ion-trap approach, so there is a clear need for arrays of ion traps that can handle a much larger number of qubits. Traps consisting of a two-dimensional electrode array have undergone significant development, but three-dimensional trap geometries can create a superior confining potential. However, existing three-dimensional approaches, as used in the most advanced experiments with trap arrays, cannot be scaled up to handle greatly increased numbers of ions. Here, we report a monolithic three-dimensional ion microtrap array etched from a silica-on-silicon wafer using conventional semiconductor fabrication technology. We have confined individual (88)Sr(+) ions and strings of up to 14 ions in a single segment of the array. We have measured motional frequencies, ion heating rates and storage times. Our results demonstrate that it should be possible to handle several tens of ion-based qubits with this approach.

  4. Application of oligonucleotide array technology for the rapid detection of pathogenic bacteria of foodborne infections.

    PubMed

    Hong, Bang-Xing; Jiang, Li-Fang; Hu, Yu-Shan; Fang, Dan-Yun; Guo, Hui-Yu

    2004-09-01

    A rapid and accurate method for detection for common pathogenic bacteria in foodborne infections was established by using oligonucleotide array technology. Nylon membrane was used as the array support. A mutation region of the 23S rRNA gene was selected as the discrimination target from 14 species (genera) of bacteria causing foodborne infections and two unrelated bacterial species. A pair of universal primers was designed for PCR amplification of the 23S rRNA gene. Twenty-one species (genera)-specific oligonucleotide detection probes were synthesized and spotted onto the nylon membranes. The 23S rRNA gene amplification products of 14 species of pathogenic bacteria were hybridized to the oligonucleotide array. Hybridization results were analyzed with digoxigenin-linked enzyme reaction. Results indicated that nine species of pathogenic bacteria (Escherichia coli, Campylobacter jejuni, Shigella dysenteriae, Vibrio cholerae, Vibrio parahaemolyticus, Proteus vulgaris, Bacillus cereus, Listeria monocytogenes and Clostridium botulinum) showed high sensitivity and specificity for the oligonucleotide array. Two other species (Salmonella enterica and Yersinia enterocolitica) gave weak cross-reaction with E. coli, but the reaction did not affect their detection. After redesigning the probes, positive hybridization results were obtained with Staphylococcus aureus, but not with Clostridium perfringens and Streptococcus pyogenes. The oligonucleotide array can also be applied to samples collected in clinical settings of foodborne infections. The superiority of oligonucleotide array over other tests lies on its rapidity, accuracy and efficiency in the diagnosis, treatment and control of foodborne infections.

  5. Feasibility of a multipurpose transceiver module for phased array radar and EW applications using RFIC technology

    NASA Astrophysics Data System (ADS)

    Al-Sarawi, Said; Hansen, Hedley; Zhu, Yingbo

    2007-12-01

    Phased array antennas have a large number of civilian and military applications. In this paper we briefly review common approaches to an integrated implementation of radar and electronic warfare digital phase array module and highlight features that are common to both of these applications. Then we discuss how the promising features of the radio frequency integrated circuit (RFIC)-based technology can be utilized in building a transceiver module that meets the requirements of both radar and electronic warfare applications with minimum number of external components. This is achieved by researching the pros and cons of the different receiver architectures and their performance from the targeted applications point of view. Then, we survey current RFIC technologies and highlight the pros and cons of these technologies and how they impact the performance of the discussed receiver architectures.

  6. Array-on-a-disk? How Blu-ray technology can be applied to molecular diagnostics.

    PubMed

    Morais, Sergi; Tortajada-Genaro, Luis; Maquieira, Angel

    2014-09-01

    This editorial comments on the balance and perspectives of compact disk technology applied to molecular diagnostics. The development of sensitive, rapid and multiplex assays using Blu-ray technology for the determination of biomarkers, drug allergens, pathogens and detection of infections would have a direct impact on diagnostics. Effective tests for use in clinical, environmental and food applications require versatile and low-cost platforms as well as cost-effective detectors. Blu-ray technology accomplishes those requirements and advances on the concept of high density arrays for massive screening to achieve the demands of point of care or in situ analysis.

  7. Design of Hybrid Nanostructural Arrays to Manipulate SERS-Active Substrates by Nanosphere Lithography.

    PubMed

    Zhao, Xiaoyu; Wen, Jiahong; Zhang, Mengning; Wang, Dunhui; Wang, Yaxin; Chen, Lei; Zhang, Yongjun; Yang, Jinghai; Du, Youwei

    2017-03-01

    An easy-handling and low-cost method is utilized to controllably fabricate nanopattern arrays as the surface-enhanced Raman scattering (SERS) active substrates with high density of SERS-active areas (hot spots). A hybrid silver array of nanocaps and nanotriangles are prepared by combining magnetron sputtering and plasma etching. By adjusting the etching time of polystyrene (PS) colloid spheres array in silver nanobowls, the morphology of the arrays can be easily manipulated to control the formation and distribution of hot spots. The experimental results show that the hybrid nanostructural arrays have large enhancement factor, which is estimated to be seven times larger than that in the array of nanocaps and three times larger than that in the array of nanorings and nanoparticles. According to the results of finite-difference time-domain simulation, the excellent SERS performance of this array is ascribed to the high density of hot spots and enhanced electromagnetic field.

  8. Cross-talk characterization of dense single-photon avalanche diode arrays in CMOS 150-nm technology

    NASA Astrophysics Data System (ADS)

    Xu, Hesong; Pancheri, Lucio; C. Braga, Leo H.; Betta, Gian-Franco Dalla; Stoppa, David

    2016-06-01

    Cross-talk characterization results of high-fill-factor single-photon avalanche diode (SPAD) arrays in CMOS 150-nm technology are reported and discussed. Three different SPAD structures were designed with two different sizes (15.6 and 25.6 μm pitch) and three guard ring widths (0.6, 1.1, and 1.6 μm). Each SPAD was implemented in an array, composed of 25 (5×5) devices, which can be separately activated. Measurement results show that the average cross-talk probability is well below 1% for the shallow-junction SPAD structure with 15.6 μm pitch and 39.9% fill factor, and 1.45% for the structure with 25.6 μm pitch and 60.6% fill factor. An increase of cross-talk probability with the excess bias voltage is observed.

  9. Monolithic microwave integrated circuit devices for active array antennas

    NASA Technical Reports Server (NTRS)

    Mittra, R.

    1984-01-01

    Two different aspects of active antenna array design were investigated. The transition between monolithic microwave integrated circuits and rectangular waveguides was studied along with crosstalk in multiconductor transmission lines. The boundary value problem associated with a discontinuity in a microstrip line is formulated. This entailed, as a first step, the derivation of the propagating as well as evanescent modes of a microstrip line. The solution is derived to a simple discontinuity problem: change in width of the center strip. As for the multiconductor transmission line problem. A computer algorithm was developed for computing the crosstalk noise from the signal to the sense lines. The computation is based on the assumption that these lines are terminated in passive loads.

  10. Application of Ultrasonic Phased Array Technology to the Detection of Defect in Composite Stiffened-structures

    NASA Astrophysics Data System (ADS)

    Zhou, Yuan-Qi; Zhan, Li-Hua

    2016-05-01

    Composite stiffened-structure consists of the skin and stringer has been widely used in aircraft fuselage and wings. The main purpose of the article is to detect the composite material reinforced structure accurately and explore the relationship between defect formation and structural elements or curing process. Based on ultrasonic phased array inspection technology, the regularity of defects in the manufacture of composite materials are obtained, the correlation model between actual defects and nondestructive testing are established. The article find that the forming quality of deltoid area in T-stiffened structure is obviously improved by pre-curing, the defects of hat-stiffened structure are affected by the mandrel. The results show that the ultrasonic phased array inspection technology can be an effectively way for the detection of composite stiffened-structures, which become an important means to control the defects of composite and improve the quality of the product.

  11. The STEP/STACBEAM experiment technology development for very large solar array deployers

    NASA Technical Reports Server (NTRS)

    Samuels, R.

    1984-01-01

    The Stacking Triangular Articulated Compact Beam (STACBEAM) is discussed with reference to structural testing experiments afforded by ground simulation and the Space Technology Experiments Platform (STEP). The STACBEAM lends itself to a deployment technique which offers a radical improvement in flexible blanket solar array technology. A system for deployment and support of a solar array blanket is described which consists of the blanket, its containment structure, the support structure and its deployer, the blanket stiffening battens, and the deployable boom standoffs. In operation, the blanket is pulled out and supported by the STACBEAM which packages next to the folded blanket. Since the STACBEAM does not rotate during extension, complete control of the blanket is maintained during extension. Deployment of this system occurs one bay at a time in a sequential manner. The deployer provides sufficient rigidity so that beam stiffness is not degraded during the deployment process.

  12. An active, flexible carbon nanotube microelectrode array for recording electrocorticograms

    NASA Astrophysics Data System (ADS)

    Chen, Yung-Chan; Hsu, Hui-Lin; Lee, Yu-Tao; Su, Huan-Chieh; Yen, Shiang-Jie; Chen, Chang-Hsiao; Hsu, Wei-Lun; Yew, Tri-Rung; Yeh, Shih-Rung; Yao, Da-Jeng; Chang, Yen-Chung; Chen, Hsin

    2011-06-01

    A variety of microelectrode arrays (MEAs) has been developed for monitoring intra-cortical neural activity at a high spatio-temporal resolution, opening a promising future for brain research and neural prostheses. However, most MEAs are based on metal electrodes on rigid substrates, and the intra-cortical implantation normally causes neural damage and immune responses that impede long-term recordings. This communication presents a flexible, carbon-nanotube MEA (CMEA) with integrated circuitry. The flexibility allows the electrodes to fit on the irregular surface of the brain to record electrocorticograms in a less invasive way. Carbon nanotubes (CNTs) further improve both the electrode impedance and the charge-transfer capacity by more than six times. Moreover, the CNTs are grown on the polyimide substrate directly to improve the adhesion to the substrate. With the integrated recording circuitry, the flexible CMEA is proved capable of recording the neural activity of crayfish in vitro, as well as the electrocorticogram of a rat cortex in vivo, with an improved signal-to-noise ratio. Therefore, the proposed CMEA can be employed as a less-invasive, biocompatible and reliable neuro-electronic interface for long-term usage.

  13. Lightweight solar array blanket tooling, laser welding and cover process technology

    NASA Technical Reports Server (NTRS)

    Dillard, P. A.

    1983-01-01

    A two phase technology investigation was performed to demonstrate effective methods for integrating 50 micrometer thin solar cells into ultralightweight module designs. During the first phase, innovative tooling was developed which allows lightweight blankets to be fabricated in a manufacturing environment with acceptable yields. During the second phase, the tooling was improved and the feasibility of laser processing of lightweight arrays was confirmed. The development of the cell/interconnect registration tool and interconnect bonding by laser welding is described.

  14. Design and Development of the Space Technology 5 (ST5) Solar Arrays

    NASA Technical Reports Server (NTRS)

    Lyons, John; Fatemi, Navid; Gamica, Robert; Sharma, Surya; Senft, Donna; Maybery, Clay

    2005-01-01

    The National Aeronautics and Space Administration's (NASA's) Space Technology 5 (ST5) is designed to flight-test the concept of miniaturized 'small size" satellites and innovative technologies in Earth's magnetosphere. Three satellites will map the intensity and direction of the magnetic fields within the inner magnetosphere. Due to the small area available for the solar arrays, and to meet the mission power requirements, very high-efficiency multijunction solar cells were selected to power the spacecraft built by NASA Goddard Space Flight Center (GSFC). This was done in partnership with the Air Force Research Lab (AFRL) through the Dual-Use Science and Technology (DUS&T) program. Emcore's InGaP/lnGaAs/Ge Advanced triple-junction (ATJ) solar cells, exhibiting an average air mass zero (AMO) efficiency of 28.0% (one-sun, 28 C), were used to populate the arrays. Each spacecraft employs 8 identical solar panels (total area of about 0.3 square meters), with 15 large-area solar cells per panel. The requirement for power is to support on-orbit average load of 13.5 W at 8.4 V, with plus or minus 5% off pointing. The details of the solar array design, development and qualification considerations, as well as ground electrical performance & shadowing analysis results are presented.

  15. Required technologies for a lunar optical UV-IR synthesis array

    NASA Technical Reports Server (NTRS)

    Johnson, Stewart W.; Wetzel, John P.

    1992-01-01

    A Lunar Optical UV-IR Synthesis Array (LOUISA) proposed to take advantage of the characteristics of the lunar environment requires appropriate advances in technology. These technologies are in the areas of contamination/interference control, test and evaluation, manufacturing, construction, autonomous operations and maintenance, power and heating/cooling, stable precision structures, optics, parabolic antennas, and communications/control. LOUISA needs to be engineered to operate for long periods with minimal intervention by humans or robots. What is essential for LOUISA operation is enforcement of a systems engineering approach that makes compatible all lunar operations associated with habitation, resource development, and science.

  16. The applicability of DOE solar cell and array technology to space power

    NASA Technical Reports Server (NTRS)

    Scott-Monck, J. A.; Stella, P. M.; Berman, P. A.

    1980-01-01

    Current trends in terrestrial photovoltaics that might benefit future space power needs are reviewed. Emphasis is placed on the Low-Cost Solar Array Project with attention given to the materials task, the silicon sheet task, the production processes and equipment task, and encapsulation. The Photovoltaic Concentrator Technology Development Project is also discussed. It is concluded that terrestrial photovoltaic technology that has either been developed to date or is currently under development will not have any significant effect on the performance or cost of solar cells and panels for space over the near term (1980-1990).

  17. Selected Technology Lab Activities Implementation Guide.

    ERIC Educational Resources Information Center

    Portland Public Schools, OR.

    These materials supplement state guides for junior high or middle school technology education programs. The materials show instructors how to implement 81 hours of new technology-related activities into existing programs. Introductory materials include a rationale, philosophy, and goals for technology education. Areas of instruction are as…

  18. Adaptation of the Biolog Phenotype MicroArrayTM Technology to Profile the Obligate Anaerobe Geobacter metallireducens

    SciTech Connect

    Joyner, Dominique; Fortney, Julian; Chakraborty, Romy; Hazen, Terry

    2010-05-17

    The Biolog OmniLog? Phenotype MicroArray (PM) plate technology was successfully adapted to generate a select phenotypic profile of the strict anaerobe Geobacter metallireducens (G.m.). The profile generated for G.m. provides insight into the chemical sensitivity of the organism as well as some of its metabolic capabilities when grown with a basal medium containing acetate and Fe(III). The PM technology was developed for aerobic organisms. The reduction of a tetrazolium dye by the test organism represents metabolic activity on the array which is detected and measured by the OmniLog(R) system. We have previously adapted the technology for the anaerobic sulfate reducing bacterium Desulfovibrio vulgaris. In this work, we have taken the technology a step further by adapting it for the iron reducing obligate anaerobe Geobacter metallireducens. In an osmotic stress microarray it was determined that the organism has higher sensitivity to impermeable solutes 3-6percent KCl and 2-5percent NaNO3 that result in osmotic stress by osmosis to the cell than to permeable non-ionic solutes represented by 5-20percent ethylene glycol and 2-3percent urea. The osmotic stress microarray also includes an array of osmoprotectants and precursor molecules that were screened to identify substrates that would provide osmotic protection to NaCl stress. None of the substrates tested conferred resistance to elevated concentrations of salt. Verification studies in which G.m. was grown in defined medium amended with 100mM NaCl (MIC) and the common osmoprotectants betaine, glycine and proline supported the PM findings. Further verification was done by analysis of transcriptomic profiles of G.m. grown under 100mM NaCl stress that revealed up-regulation of genes related to degradation rather than accumulation of the above-mentioned osmoprotectants. The phenotypic profile, supported by additional analysis indicates that the accumulation of these osmoprotectants as a response to salt stress does not

  19. Building Technologies Program Key Activities

    SciTech Connect

    2011-12-15

    The Building Technologies Program (BTP) employs a balanced approach to making buildings more energy efficient. The three pillars of our program, research and development (R&D), market stimulation, and building and equipment standards, help meet our strategic vision.

  20. 77 FR 52317 - Record of Decision for Surveillance Towed Array Sensor System Low Frequency Active Sonar

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-29

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Department of the Navy Record of Decision for Surveillance Towed Array Sensor System Low Frequency Active... Array Sensor System Low Frequency Active (SURTASS LFA) sonar systems with certain...

  1. Feed array metrology and correction layer for large antenna systems in ASIC mixed signal technology

    NASA Astrophysics Data System (ADS)

    Centureli, F.; Scotti, G.; Tommasino, P.; Trifiletti, A.; Romano, F.; Cimmino, R.; Saitto, A.

    2014-08-01

    The paper deals with a possible use of the feed array present in a large antenna system, as a layer for measuring the antenna performance with a self-test procedure and a possible way to correct residual errors of the Antenna geometry and of the antenna distortions. Focus has been concentrated on a few key critical elements of a possible feed array metrology program. In particular, a preliminary contribution to the design and development of the feed array from one side, and the subsystem dedicated to antenna distortion monitoring and control from the other, have been chosen as the first areas of investigation. Scalability and flexibility principles and synergic approach with other coexistent technologies have been assumed of paramount importance to ensure ease of integrated operation and therefore allowing in principle increased performance and efficiency. The concept is based on the use of an existing feed array grid to measure antenna distortion with respect to the nominal configuration. Measured data are then processed to develop a multilayer strategy to control the mechanical movable devices (when existing) and to adjust the residual fine errors through a software controlled phase adjustment of the existing phase shifter The signal from the feed array is converted passing through a FPGA/ASIC level to digital data channels. The kind of those typically used for the scientific experiments. One additional channel is used for monitoring the antenna distortion status. These data are processed to define the best correction strategy, based on a software managed control system capable of operating at three different levels of the antenna system: reflector rotation layer, sub reflector rotation and translation layer (assuming the possibility of controlling a Stewart machine), phase shifter of the phased array layer. The project is at present in the design phase, a few elements necessary for a sound software design of the control subsystem have been developed at a

  2. Graphene-based carbon-layered electrode array technology for neural imaging and optogenetic applications.

    PubMed

    Park, Dong-Wook; Schendel, Amelia A; Mikael, Solomon; Brodnick, Sarah K; Richner, Thomas J; Ness, Jared P; Hayat, Mohammed R; Atry, Farid; Frye, Seth T; Pashaie, Ramin; Thongpang, Sanitta; Ma, Zhenqiang; Williams, Justin C

    2014-10-20

    Neural micro-electrode arrays that are transparent over a broad wavelength spectrum from ultraviolet to infrared could allow for simultaneous electrophysiology and optical imaging, as well as optogenetic modulation of the underlying brain tissue. The long-term biocompatibility and reliability of neural micro-electrodes also require their mechanical flexibility and compliance with soft tissues. Here we present a graphene-based, carbon-layered electrode array (CLEAR) device, which can be implanted on the brain surface in rodents for high-resolution neurophysiological recording. We characterize optical transparency of the device at >90% transmission over the ultraviolet to infrared spectrum and demonstrate its utility through optical interface experiments that use this broad spectrum transparency. These include optogenetic activation of focal cortical areas directly beneath electrodes, in vivo imaging of the cortical vasculature via fluorescence microscopy and 3D optical coherence tomography. This study demonstrates an array of interfacing abilities of the CLEAR device and its utility for neural applications.

  3. Array microscopy technology and its application to digital detection of Mycobacterium tuberculosis

    NASA Astrophysics Data System (ADS)

    McCall, Brian P.

    Tuberculosis causes more deaths worldwide than any other curable infectious disease. This is the case despite tuberculosis appearing to be on the verge of eradication midway through the last century. Efforts at reversing the spread of tuberculosis have intensified since the early 1990s. Since then, microscopy has been the primary frontline diagnostic. In this dissertation, advances in clinical microscopy towards array microscopy for digital detection of Mycobacterium tuberculosis are presented. Digital array microscopy separates the tasks of microscope operation and pathogen detection and will reduce the specialization needed in order to operate the microscope. Distributing the work and reducing specialization will allow this technology to be deployed at the point of care, taking the front-line diagnostic for tuberculosis from the microscopy center to the community health center. By improving access to microscopy centers, hundreds of thousands of lives can be saved. For this dissertation, a lens was designed that can be manufactured as 4x6 array of microscopes. This lens design is diffraction limited, having less than 0.071 waves of aberration (root mean square) over the entire field of view. A total area imaged onto a full-frame digital image sensor is expected to be 3.94 mm2, which according to tuberculosis microscopy guidelines is more than sufficient for a sensitive diagnosis. The design is tolerant to single point diamond turning manufacturing errors, as found by tolerance analysis and by fabricating a prototype. Diamond micro-milling, a fabrication technique for lens array molds, was applied to plastic plano-concave and plano-convex lens arrays, and found to produce high quality optical surfaces. The micro-milling technique did not prove robust enough to produce bi-convex and meniscus lens arrays in a variety of lens shapes, however, and it required lengthy fabrication times. In order to rapidly prototype new lenses, a new diamond machining technique was

  4. Image-guided ultrasound phased arrays are a disruptive technology for non-invasive therapy

    NASA Astrophysics Data System (ADS)

    Hynynen, Kullervo; Jones, Ryan M.

    2016-09-01

    Focused ultrasound offers a non-invasive way of depositing acoustic energy deep into the body, which can be harnessed for a broad spectrum of therapeutic purposes, including tissue ablation, the targeting of therapeutic agents, and stem cell delivery. Phased array transducers enable electronic control over the beam geometry and direction, and can be tailored to provide optimal energy deposition patterns for a given therapeutic application. Their use in combination with modern medical imaging for therapy guidance allows precise targeting, online monitoring, and post-treatment evaluation of the ultrasound-mediated bioeffects. In the past there have been some technical obstacles hindering the construction of large aperture, high-power, densely-populated phased arrays and, as a result, they have not been fully exploited for therapy delivery to date. However, recent research has made the construction of such arrays feasible, and it is expected that their continued development will both greatly improve the safety and efficacy of existing ultrasound therapies as well as enable treatments that are not currently possible with existing technology. This review will summarize the basic principles, current statures, and future potential of image-guided ultrasound phased arrays for therapy.

  5. Adaptive nulling at HF using a compact array of active parasitic antennas

    NASA Astrophysics Data System (ADS)

    Jones, T. E.; Zeger, A. E.

    1985-03-01

    This parasitic array is a promising method of building an adaptive array in a tiny aperture. This is particularly attractive for HF. Both theory and experimental results are presented. The theory is established with respect to two models of a compact array, an impedance model and a transmission line model. The relationship between the models are derived. The models are then used to explore the null forming and adaptive control, with an emphasis on active terminations. Zeger-Abrams designed an electronically variable active termination. Experimental results were obtained from an array of both passive and active terminations. Empirical results with active complex-valued terminations demonstrated the feasibility of simultaneously nulling multiple HF jammers with an adaptively controlled compact array having parasitic auxilliary elements and an unweighted main antenna. Finally, an algorithm to adaptively control the active terminations is derived.

  6. Microfabrication Technology for Large Lekid Arrays: From Nika2 to Future Applications

    NASA Astrophysics Data System (ADS)

    Goupy, J.; Adane, A.; Benoit, A.; Bourrion, O.; Calvo, M.; Catalano, A.; Coiffard, G.; Hoarau, C.; Leclercq, S.; Le Sueur, H.; Macias-Perez, J.; Monfardini, A.; Peck, I.; Schuster, K.

    2016-08-01

    The lumped element kinetic inductance detectors (LEKID) demonstrated full maturity in the New IRAM KID Arrays (NIKA) instrument. These results allow directly comparing LEKID performance with other competing technologies (TES, doped silicon) in the mm and sub-mm range. A continuing effort is ongoing to improve the microfabrication technologies and concepts in order to satisfy the requirements of new instruments. More precisely, future satellites dedicated to cosmic microwave background (CMB) studies will require the same focal plane technology to cover, at least, the frequency range of 60-600 GHz. Aluminium LEKID developed for NIKA have so far demonstrated, under real telescope conditions, a performance approaching photon noise limitation in the band 120-300 GHz. By implementing superconducting bi-layers, we recently demonstrated LEKID arrays working in the range 80-120 GHz and with sensitivities approaching the goals for CMB missions. NIKA itself (350 pixels) is followed by a more ambitious project requiring several thousand (3000-5000) pixels. NIKA2 has been installed in October 2015 at the IRAM 30-m telescope. We will describe in detail the technological improvements that allowed a relatively harmless tenfold up-scaling in pixels count without degrading the initial sensitivity. In particular, we will briefly describe a solution to simplify the difficult fabrication step linked to the slot-line propagation mode in coplanar waveguide.

  7. Application of multi-channel photoelastic imaging technology in array type ultrasonic nondestructive testing

    NASA Astrophysics Data System (ADS)

    Fan, Zhen-zhong; Bi, Chao

    2015-08-01

    With the rapid development of modern nondestructive testing technologies, ultrasonic phased array and Ultrasonic array testing technology has been used widely, at the same time the propagation process of ultrasonic in the material becomes more and more complex. In order to make the ultrasonic propagation path become visible and researchers can observe the acoustic field directly, considering the properties of the ultrasonic as a stress wave, according to the theory of polarized light interference, a multi-channel dynamic photoelastic imaging system is developed successfully. The system can generate many kinds of focusing ultrasonic fields in optical specimen by controlling the ultrasonic transmission delay time of each equipment channel, and the system has the ability to simulate the acoustic field's focusing process of the ultrasonic phased array. The image shot by CCD camera reflects the propagation process of the acoustic field in the specimen, and the dynamic video is formed under control of the timing circuit, and the system has the ability to save the captured image in the computer.

  8. Ka-band Dielectric Waveguide Antenna Array for Millimeter Wave Active Imaging System

    NASA Astrophysics Data System (ADS)

    Fang, Weihai; Fei, Peng; Nian, Feng; Yang, Yujie; Feng, Keming

    2014-11-01

    Ka-band compact dielectric waveguide antenna array for active imaging system is given. Antenna array with WR28 metal waveguide direct feeding is specially designed with small size, high gain, good radiation pattern, easy realization, low insertion loss and low mutual coupling. One practical antenna array for 3-D active imaging system is shown with theoretic analysis and experimental results. The mutual coupling of transmitting and receiving units is less than -30dB, the gain from 26.5GHz to 40GHz is (12-16) dB. The results in this paper provide guidelines for the designing of millimeter wave dielectric waveguide antenna array.

  9. Structural Engineering. Technology Learning Activity. Teacher Edition. Technology Education Series.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This curriculum guide provides technology learning activities designed to prepare students in grades 6-10 to work in the world of the future. The 8-day course provides exploratory, hands-on learning activities and information that can enhance the education of students of all types in an integrated curriculum that provides practical applications of…

  10. Drafting. Technology Learning Activity. Teacher Edition. Technology Education Series.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This packet of technology learning activity (TLA) materials for drafting for students in grades 6-10 consists of an instructor's section and student materials. The instructor's section contains background information, suggested activities, and a list of suggested resources. A lesson plan for the 8-day module includes assignments; equipment, tools,…

  11. Problem Solving. Technology Learning Activity. Teacher Edition. Technology Education Series.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This curriculum guide provides technology learning activities designed to prepare students in grades 6-10 to work in the world of the future. The 8-day course provides exploratory, hands-on learning activities and information that can enhance the education of students of all types in an integrated curriculum that provides practical applications of…

  12. The status of lightweight photovoltaic space array technology based on amorphous silicon solar cells

    NASA Technical Reports Server (NTRS)

    Hanak, Joseph J.; Kaschmitter, Jim

    1991-01-01

    Ultralight, flexible photovoltaic (PV) array of amorphous silicon (a-Si) was identified as a potential low cost power source for small satellites. A survey was conducted of the status of the a-Si PV array technology with respect to present and future performance, availability, cost, and risks. For existing, experimental array blankets made of commercial cell material, utilizing metal foil substrates, the Beginning of Life (BOL) performance at Air Mass Zero (AM0) and 35 C includes total power up to 200 W, power per area of 64 W/sq m and power per weight of 258 W/kg. Doubling of power per weight occurs when polyimide substrates are used. Estimated End of Life (EOL) power output after 10 years in a nominal low earth orbit would be 80 pct. of BOL, the degradation being due to largely light induced effects (-10 to -15 pct.) and in part (-5 pct.) to space radiation. Predictions for the year 1995 for flexible PV arrays, made on the basis of published results for rigid a-Si modules, indicate EOL power output per area and per weight of 105 W/sq m and 400 W/kg, respectively, while predictions for the late 1990s based on existing U.S. national PV program goals indicate EOL values of 157 W/sq m and 600 W/kg. Cost estimates by vendors for 200 W ultralight arrays in volume of over 1000 units range from $100/watt to $125/watt. Identified risks include the lack of flexible, space compatible encapsulant, the lack of space qualification effort, recent partial or full acquisitions of US manufacturers of a-Si cells by foreign firms, and the absence of a national commitment for a long range development program toward developing of this important power source for space.

  13. Determination of somatic oncogenic mutations linked to target-based therapies using MassARRAY technology

    PubMed Central

    Llorca-Cardeñosa, Marta J.; Mongort, Cristina; Alonso, Elisa; Navarro, Samuel; Burgues, Octavio; Vivancos, Ana; Cejalvo, Juan Miguel; Perez-Fidalgo, José Alejandro; Roselló, Susana; Ribas, Gloria; Cervantes, Andrés

    2016-01-01

    Somatic mutation analysis represents a useful tool in selecting personalized therapy. The aim of our study was to determine the presence of common genetic events affecting actionable oncogenes using a MassARRAY technology in patients with advanced solid tumors who were potential candidates for target-based therapies. The analysis of 238 mutations across 19 oncogenes was performed in 197 formalin-fixed paraffin-embedded samples of different tumors using the OncoCarta Panel v1.0 (Sequenom Hamburg, Germany). Of the 197 specimens, 97 (49.2%) presented at least one mutation. Forty-nine different oncogenic mutations in 16 genes were detected. Mutations in KRAS and PIK3CA were detected in 40/97 (41.2%) and 30/97 (30.9%) patients respectively. Thirty-one patients (32.0%) had mutations in two genes, 20 of them (64.5%) initially diagnosed with colorectal cancer. The co-occurrence of mutation involved mainly KRAS, PIK3CA, KIT and RET. Mutation profiles were validated using a customized panel and the Junior Next-Generation Sequencing technology (GS-Junior 454, Roche). Twenty-eight patients participated in early clinical trials or received specific treatments according to the molecular characterization (28.0%). MassARRAY technology is a rapid and effective method for identifying key cancer-driving mutations across a large number of samples, which allows for a more appropriate selection for personalized therapies. PMID:26968814

  14. High-resolution focal plane array IR detection modules and digital signal processing technologies at AIM

    NASA Astrophysics Data System (ADS)

    Cabanski, Wolfgang A.; Breiter, Rainer; Koch, R.; Mauk, Karl-Heinz; Rode, Werner; Ziegler, Johann; Eberhardt, Kurt; Oelmaier, Reinhard; Schneider, Harald; Walther, Martin

    2000-07-01

    Full video format focal plane array (FPA) modules with up to 640 X 512 pixels have been developed for high resolution imaging applications in either mercury cadmium telluride (MCT) mid wave (MWIR) infrared (IR) or platinum silicide (PtSi) and quantum well infrared photodetector (QWIP) technology as low cost alternatives to MCT for high performance IR imaging in the MWIR or long wave spectral band (LWIR). For the QWIP's, a new photovoltaic technology was introduced for improved NETD performance and higher dynamic range. MCT units provide fast frame rates > 100 Hz together with state of the art thermal resolution NETD < 20 mK for short snapshot integration times of typically 2 ms. PtSi and QWIP modules are usually operated in a rolling frame integration mode with frame rates of 30 - 60 Hz and provide thermal resolutions of NETD < 80 mK for PtSi and NETD < 20 mK for QWIP, respectively. Due to the lower quantum efficiency compared to MCT, however, the integration time is typically chosen to be as long 10 - 20 ms. The heat load of the integrated detector cooler assemblies (IDCAs) could be reduced to an amount as low, that a 1 W split liner cooler provides sufficient cooling power to operate the modules -- including the QWIP with 60 K operation temperature -- at ambient temperatures up to 65 degrees Celsius. Miniaturized command/control electronics (CCE) available for all modules provide a standardized digital interface, with 14 bit analogue to digital conversion for state to the art correctability, access to highly dynamic scenes without any loss of information and simplified exchangeability of the units. New modular image processing hardware platforms and software for image visualization and nonuniformity correction including scene based self learning algorithms had to be developed to accomplish for the high data rates of up to 18 M pixels/s with 14-bit deep data, allowing to take into account nonlinear effects to access the full NETD by accurate reduction of residual

  15. Multiple Seismic Array Observations for Tracing Deep Tremor Activity in Western Shikoku, Japan

    NASA Astrophysics Data System (ADS)

    Takeda, T.; Matsuzawa, T.; Shiomi, K.; Obara, K.

    2011-12-01

    Deep non-volcanic tremors become very active during episodic slow-slip events in western Japan and Cascadia. The episodic tremor and slow-slip events in western Shikoku, Japan, occur at a typical interval of 6 months. Recently, it has been reported that tremor migration activity is complex and shows different migrating directions depending on time scales (Ghosh et al., 2010). Such characteristics of tremor are important to understand the mechanism of tremor and the relationship between tremor and SSEs. However it is difficult to determine the location of tremors with high accuracy because tremors show faint signals and make the identification of P/S-wave arrivals difficult. Seismic array analysis is useful to evaluate tremor activity, especially to estimate the arrival direction of seismic energy (e.g. Ueno et al., 2010, Ghosh et al., 2010), as it can distinguish multiple tremor sources occurring simultaneously. Here, we have conducted seismic array observation and analyzed seismic data during tremor activity by applying the MUSIC method to trace tremor location and its migration in western Shikoku. We have installed five seismic arrays in western Shikoku since January 2011. One of the arrays contains 30 stations with 3-component seismometers with a natural frequency of 2 Hz (Type-L array). The array aperture size is 2 km and the mean interval between stations is approximately 200 m. Each of the other arrays (Type-S array) contains 9 seismic stations with the same type of seismometers of the Type-L array, and is deployed surrounding the Type-L array. The small array aperture size is 800 m and its mean station interval is approximately 150 m. All array stations have recorded continuous waveform data at a sampling of 200Hz. In May 2011, an episodic tremor and a short-term slip event occurred for the first time during the observation period. We could retrieve the array seismic data during the whole tremor episode. The analysis of data from the type-L array confirms

  16. Analysis and fabrication of corner cube array based on laser direct writing technology.

    PubMed

    Lou, Yimin; Wang, Hui; Liu, Qingkun; Shi, Yaocheng; He, Sailing

    2010-10-10

    A detailed analysis of corner cube array (CCA) structure is carried out using the commercially available ray-tracing software ZEMAX. The retroreflective properties of CCA for short-range and long-range propagation are compared. An improved CCA structure with a relatively low structural depth (compared with rectangular CCA) is designed and analyzed. Higher retroreflectance (compared with triangular CCA) at a specific incident angle is proved by ray tracing. Two kinds of CCA structures, including the improved CCA, have been fabricated using laser direct writing technology. The fabrication results are qualified by three-dimensional shape measurement and ray tracing.

  17. Review of Concepts and Applications for Multispectral/Hyperspectral Focal Plane Array (FPA) Technology

    NASA Technical Reports Server (NTRS)

    McAdoo, James A.

    2001-01-01

    Multispectral, and ultimately hyperspectral, focal plane arrays (FPAs) represent the logical extension of two-color FPA technology, which has already shown its utility in military applications. Incorporating the spectral discrimination function directly in the FPA would offer the potential for orders-of-magnitude increase in remote sensor system performance. It would allow reduction or even elimination of optical components currently required to provide spectral discrimination in atmospheric remote sensors. The result would be smaller, simpler instruments with higher performance than exist today.

  18. Assessment of weld quality of aerospace grade metals by using ultrasonic matrix phased array technology

    NASA Astrophysics Data System (ADS)

    Na, Jeong K.; Gleeson, Sean T.

    2014-03-01

    Advantages of two dimensional electronic ultrasonic beam focusing, steering and scanning with the matrix phased array (MPA) technology has been used to visualize the conditions of resistance spot welds in auto vehicle grade advanced high strength steel carbon steels nondestructively. Two of the commonly used joining techniques, resistance spot welding and resistance seam welding, for thin aerospace grade plates made of aluminum, titanium, and stainless steels have also been inspected with the same MPA NDE system. In this study, a detailed discussions of the current MPA based ultrasonic real time imaging methodology has been made followed by some of the NDT results obtained with various welded test coupons.

  19. One GigaSample Per Second Data Acquisition using Available Gate Array Technology

    NASA Technical Reports Server (NTRS)

    Wagner, K.W.

    1999-01-01

    A new National Aeronautics and Space Administration instrument forced demanding requirements upon its altimeter digitizer system. Eight-bit data would be generated at a rate of one billion samples per second. NASA had never before attempted to capture such high-speed data in the radiation, low-power, no-convective-cooling, limited-board-area environment of space. This presentation describes how the gate array technology available at the time of the design was used to implement this one gigasample per second data acquisition system

  20. Simulation research on beam steering technology based on optical phased array

    NASA Astrophysics Data System (ADS)

    Tian, Junlin; Pan, Xudong

    2015-02-01

    The principle of beam steering technology based on optical phased array (OPA), which is composed of individual phase-modulating units, is introduced. By use of Fraunhofer diffraction and Fourier transformation, the OPA models are established. The influence of main parameters of OPA on beam steering efficiency, including duty ratio (ratio of effective unit size to total unit size), total unit size, unit number, and steering angle, is simulated and analyzed. It shows that beam steering efficiency of OPA is improved with larger duty ratio, smaller total unit size, and smaller steering angle, while the number of units has a very small impact on beam steering efficiency.

  1. Active Control of Solar Array Dynamics During Spacecraft Maneuvers

    NASA Technical Reports Server (NTRS)

    Ross, Brant A.; Woo, Nelson; Kraft, Thomas G.; Blandino, Joseph R.

    2016-01-01

    Recent NASA mission plans require spacecraft to undergo potentially significant maneuvers (or dynamic loading events) with large solar arrays deployed. Therefore there is an increased need to understand and possibly control the nonlinear dynamics in the spacecraft system during such maneuvers. The development of a nonlinear controller is described. The utility of using a nonlinear controller to reduce forces and motion in a solar array wing during a loading event is demonstrated. The result is dramatic reductions in system forces and motion during a 10 second loading event. A motion curve derived from the simulation with the closed loop controller is used to obtain similar benefits with a simpler motion control approach.

  2. ActiveSeismoPick3D - automatic first arrival determination for large active seismic arrays

    NASA Astrophysics Data System (ADS)

    Paffrath, Marcel; Küperkoch, Ludger; Wehling-Benatelli, Sebastian; Friederich, Wolfgang

    2016-04-01

    We developed a tool for automatic determination of first arrivals in active seismic data based on an approach, that utilises higher order statistics (HOS) and the Akaike information criterion (AIC), commonly used in seismology, but not in active seismics. Automatic picking is highly desirable in active seismics as the number of data provided by large seismic arrays rapidly exceeds of what an analyst can evaluate in a reasonable amount of time. To bring the functionality of automatic phase picking into the context of active data, the software package ActiveSeismoPick3D was developed in Python. It uses a modified algorithm for the determination of first arrivals which searches for the HOS maximum in unfiltered data. Additionally, it offers tools for manual quality control and postprocessing, e.g. various visualisation and repicking functionalities. For flexibility, the tool also includes methods for the preparation of geometry information of large seismic arrays and improved interfaces to the Fast Marching Tomography Package (FMTOMO), which can be used for the prediction of travel times and inversion for subsurface properties. Output files are generated in the VTK format, allowing the 3D visualization of e.g. the inversion results. As a test case, a data set consisting of 9216 traces from 64 shots was gathered, recorded at 144 receivers deployed in a regular 2D array of a size of 100 x 100 m. ActiveSeismoPick3D automatically checks the determined first arrivals by a dynamic signal to noise ratio threshold. From the data a 3D model of the subsurface was generated using the export functionality of the package and FMTOMO.

  3. Introductory Industrial Technology I. Laboratory Activities.

    ERIC Educational Resources Information Center

    Towler, Alan L.; And Others

    This guide contains 36 learning modules intended for use by technology teachers and students in grades 7 and 8. Each module includes a student laboratory activity and instructor's resource sheet. Each student activity includes the following: activity topic and overview, challenge statement, objectives, vocabulary/concepts reinforced,…

  4. Introductory Industrial Technology II. Laboratory Activities.

    ERIC Educational Resources Information Center

    Towler, Alan L.

    This guide contains 29 learning modules intended for use by technology teachers and students in grade 8. Each module includes a student laboratory activity and instructor's resource sheet. Each student activity includes the following: activity topic and overview, challenge statement, objectives, vocabulary/concepts reinforced, equipment/supplies,…

  5. Classroom Activities in Transportation: Technology Education.

    ERIC Educational Resources Information Center

    Wisconsin State Dept. of Public Instruction, Madison.

    This curriculum supplement was designed to correlate directly with "A Guide to Curriculum Planning in Technology Education," published by the Wisconsin Department of Public Instruction. It is also a companion book to three other classroom activity compilations, one in each of the other three major systems of technology--manufacturing,…

  6. Development of the nanotiter plate for use in antibody and cell array technologies

    NASA Astrophysics Data System (ADS)

    Ramdutt, Devin; Lui, Rodney; Davies, Kerrie; Boswell, Rod W.; dos Remedios, Cristobal G.; Charles, Christine; Bilek, Marcela M.; McKenzie, David R.

    2005-02-01

    The design and fabrication of biomedical tools using techniques common in microelectronics is becoming established procedure. In our research, we use gaseous plasma dry etching to form microstructures on silicon wafers. These are intended for use in capturing and binding antibodies and live cells in an array to be used in High Throughput Screening (HTS) and High Content Screening (HCS) of new pharmaceuticals. We call this new arraying plate the "Nanotiter" plate. The benefit of our design (100 x 100 wells in a 25 x 25 mm array) over current 96-, 384- and 1056-well microtiter plates are that the number of samples (wells) that can be tested in one plate scan can be substantially increased, the wells can be rapidly and effectively washed, and the well surfaces can be modified to modulate ligand binding. Simple crowding of wells on a plate can result in cross contamination of samples in adjacent wells during the washing. Furthermore, motile cells may migrate between the wells. 1056 microtiter plates currently cannot be washed, and washing 384 plates is problematic. Our design incorporates plasma-deposited polymers that functionally bind antibodies (or other proteins) in but not between wells. Furthermore, the wells can be shaped to minimize cell migration. Inverting the plate on a wash solution allows unbound cells to simply fall away under gravity thus minimising the contamination of adjacent wells. Thus, our Nanotiter plate represents a substantial improvement over existing technology.

  7. System-Level Integrated Circuit (SLIC) Technology Development for Phased Array Antenna Applications

    NASA Technical Reports Server (NTRS)

    Windyka, John A.; Zablocki, Ed G.

    1997-01-01

    This report documents the efforts and progress in developing a 'system-level' integrated circuit, or SLIC, for application in advanced phased array antenna systems. The SLIC combines radio-frequency (RF) microelectronics, digital and analog support circuitry, and photonic interfaces into a single micro-hybrid assembly. Together, these technologies provide not only the amplitude and phase control necessary for electronic beam steering in the phased array, but also add thermally-compensated automatic gain control, health and status feedback, bias regulation, and reduced interconnect complexity. All circuitry is integrated into a compact, multilayer structure configured for use as a two-by-four element phased array module, operating at 20 Gigahertz, using a Microwave High-Density Interconnect (MHDI) process. The resultant hardware is constructed without conventional wirebonds, maintains tight inter-element spacing, and leads toward low-cost mass production. The measured performances and development issues associated with both the two-by-four element module and the constituent elements are presented. Additionally, a section of the report describes alternative architectures and applications supported by the SLIC electronics. Test results show excellent yield and performance of RF circuitry and full automatic gain control for multiple, independent channels. Digital control function, while suffering from lower manufacturing yield, also proved successful.

  8. Marshall Space Flight Center ECLSS technology activities

    NASA Technical Reports Server (NTRS)

    Wieland, Paul

    1990-01-01

    Viewgraphs on Environmental Control and Life Support System (ECLSS) technology activities are presented. Topics covered include: analytical development; ECLSS modeling approach; example of water reclamation modeling needs; and hardware development and testing.

  9. Simultaneous and rapid detection of multiple pesticide and veterinary drug residues by suspension array technology.

    PubMed

    Liu, Nan; Gao, Zhixian; Ma, Hongwei; Su, Pu; Ma, Xinhua; Li, Xiaoli; Ou, Guorong

    2013-03-15

    Suspension array technology is proposed for the simultaneous quantitative determination of seven kinds of pesticide and veterinary drug residues, namely, atrazine, chloramphenicol, carbaryl, clenbuterol, 17-β-estradiol, imidacloprid, and tylosin. The assay is simple and can be accomplished within 2h without repeated pumping and washing steps unlike conventional suspension arrays. The hapten-protein conjugate-coated beads bind to their complementary biotinylated antibodies using a competitive immunoassay format. The coefficients of determination R(2) for six targets were greater than 0.992, whereas that for atrazine was 0.961, which indicate good logistic correlations. The dynamic ranges for the seven targets in the 7-plex assay ranged from 2 log units to 4 log units(1.60×10(0)-1.64×10(3), 5.12×10(-2)-1.60×10(2), 1.00×10(0)-3.13×10(3), 4.00×10(-1)-4.10×10(2), 4.00×10(-1)-4.10×10(2), 5.12×10(-2)-1.60×10(2), and 2.00×10(0)-4.00×10(2)ngmL(-1)). The minimum detection concentrations of chloramphenicol, carbaryl, clenbuterol and 17-β-estradiol in the suspension array (0.05, 1.00, 0.40 and 0.40 ng mL(-1)) were lower than the corresponding limits of detection (0.25, 6.60, 24.23 and 13.96 ng mL(-1)) of using an indirect competitive enzyme-linked immunosorbent assay. Environmental scanning electron microscope was employed to characterize the bead surface, which directly confirmed the reactions on the beads. The suspension array is more flexible and feasible than ELISA for the fast quantitative analysis of pesticide and veterinary drug residues.

  10. Characterization of Service Induced Flaws on the Far Side of Austenitic Welds Using Phased Array Technology

    SciTech Connect

    Anderson, Michael T.; Cumblidge, Stephen E.

    2004-01-01

    Conventional ultrasonic testing methods continue to exhibit problems for applications involving coarse-grained structures. Pacific Northwest National Laboratory is evaluating the capabilities and limitations of phased array (PA) technology to detect service-type flaws in these coarse-grained materials. The work is being sponsored by the U.S. Nuclear Regulatory Commission, Office of Research. Work to determine detection capabilities through welds with varied grain structures is being explored to provide a better understanding of the acoustic properties of these welded structures. Piping specimens with welds fabricated in vertical and horizontal positions to simulate field conditions have been studied. The insights gained from the austenitic piping will be applied to dissimilar metal weld configurations, corrosion resistant clad piping and cast stainless steels. This paper presents results for using PA ultrasonic technology to determine the effectiveness of detecting and accurately characterizing flaws on the far-side of austenitic piping welds.

  11. MicroArray Facility: a laboratory information management system with extended support for Nylon based technologies

    PubMed Central

    Honoré, Paul; Granjeaud, Samuel; Tagett, Rebecca; Deraco, Stéphane; Beaudoing, Emmanuel; Rougemont, Jacques; Debono, Stéphane; Hingamp, Pascal

    2006-01-01

    Background High throughput gene expression profiling (GEP) is becoming a routine technique in life science laboratories. With experimental designs that repeatedly span thousands of genes and hundreds of samples, relying on a dedicated database infrastructure is no longer an option. GEP technology is a fast moving target, with new approaches constantly broadening the field diversity. This technology heterogeneity, compounded by the informatics complexity of GEP databases, means that software developments have so far focused on mainstream techniques, leaving less typical yet established techniques such as Nylon microarrays at best partially supported. Results MAF (MicroArray Facility) is the laboratory database system we have developed for managing the design, production and hybridization of spotted microarrays. Although it can support the widely used glass microarrays and oligo-chips, MAF was designed with the specific idiosyncrasies of Nylon based microarrays in mind. Notably single channel radioactive probes, microarray stripping and reuse, vector control hybridizations and spike-in controls are all natively supported by the software suite. MicroArray Facility is MIAME supportive and dynamically provides feedback on missing annotations to help users estimate effective MIAME compliance. Genomic data such as clone identifiers and gene symbols are also directly annotated by MAF software using standard public resources. The MAGE-ML data format is implemented for full data export. Journalized database operations (audit tracking), data anonymization, material traceability and user/project level confidentiality policies are also managed by MAF. Conclusion MicroArray Facility is a complete data management system for microarray producers and end-users. Particular care has been devoted to adequately model Nylon based microarrays. The MAF system, developed and implemented in both private and academic environments, has proved a robust solution for shared facilities and

  12. Flexible transistor active matrix array with all screen-printed electrodes

    NASA Astrophysics Data System (ADS)

    Peng, Boyu; Lin, Jiawei; Chan, Paddy K. L.

    2013-09-01

    Flexible transistor active matrix array is fabricated on PEN substrate using all screen-printed gate, source and drain electrodes. Parylene-C and DNTT act as gate dielectric layer and semiconductor, respectively. The transistor possesses high mobility (0.33 cm2V-1 s-1), large on/off ratio (< 106) and low leakage current (~10 pA). Active matrix array consists of 10×10 transistors were demonstrated. Transistors exhibited average mobility of 0.29 cm2V-1s-1 and on/off ratio larger than 104 in array form. In the transistor array, we achieve 75μm channel length and a size of 2 mm × 2 mm for each element in the array which indicates the current screen-printing method has large potential in large-area circuits and display applications.

  13. Assessment of High-Voltage Photovoltaic Technologies for the Design of a Direct Drive Hall Effect Thruster Solar Array

    NASA Technical Reports Server (NTRS)

    Mikellides, I. G.; Jongeward, G. A.; Schneider, T.; Carruth, M. R.; Peterson, T.; Kerslake, T. W.; Snyder, D.; Ferguson, D.; Hoskins, A.

    2004-01-01

    A three-year program to develop a Direct Drive Hall-Effect Thruster system (D2HET) begun in 2001 as part of the NASA Advanced Cross-Enterprise Technology Development initiative. The system, which is expected to reduce significantly the power processing, complexity, weight, and cost over conventional low-voltage systems, will employ solar arrays that operate at voltages higher than (or equal to) 300 V. The lessons learned from the development of the technology also promise to become a stepping-stone for the production of the next generation of power systems employing high voltage solar arrays. This paper summarizes the results from experiments conducted mainly at the NASA Marshal Space Flight Center with two main solar array technologies. The experiments focused on electron collection and arcing studies, when the solar cells operated at high voltages. The tests utilized small coupons representative of each solar array technology. A hollow cathode was used to emulate parts of the induced environment on the solar arrays, mostly the low-energy charge-exchange plasma (1012-1013 m-3 and 0.5-1 eV). Results and conclusions from modeling of electron collection are also summarized. The observations from the total effort are used to propose a preliminary, new solar array design for 2 kW and 30-40 kW class, deep space missions that may employ a single or a cluster of Hall- Effect thrusters.

  14. An active alignment scheme for the MPTS array

    NASA Technical Reports Server (NTRS)

    Iwasaki, R.

    1980-01-01

    In order to maximize the efficiency of the microwave power transmission system (MPTS), the surface of the array antenna must be extremely flat, which is difficult to achieve using passive techniques over the 1 km dimensions of the array. In order to achieve and maintain this required flatness, a rotating laser beam used for leveling applications on Earth was utilized as a reference system. A photoconductive sensor with a reflective collecting surface was used to determine the displacement and polarity of any misalignment and automatically engage a stepping motor to drive a variable-length mechanism to make the necessary corrections. Once aligned, little power is dissipated since a nulling bridge circuit that centers on the beam is used, an important alignment feature since even laser beams broaden considerably at 1 km distances.

  15. An active alignment scheme for the MPTS array

    NASA Astrophysics Data System (ADS)

    Iwasaki, R.

    1980-12-01

    In order to achieve and maintain required flatness of the antenna array, a rotating laser beam used for leveling applications on earth was utilized as a reference system. A photoconductive sensor with a reflective collecting surface determines the displacement and polarity of any misalignment and automatically engages a stepping motor to drive a variable-length mechanism to make the necessary corrections. Once aligned, little power is dissipated since a nulling bridge circuit that centers on the beam is used. A three-point subarray alignment arrangement is described which independently adjusts, in the three orthogonal directions, the height and tilt of subarrays within the MPTS array and readily adapts to any physical distortions of the secondary structure (such as that resulting from severe temperature extremes caused by an eclipse of the Sun). It is shown that only one rotating laser system is required since optical blockage is minimal on the array surface and that it is possible to incorporate a number of redundant laser systems for reliability without affecting the overall performance.

  16. An active alignment scheme for the MPTS array. [contour sensors

    NASA Technical Reports Server (NTRS)

    Iwasaki, R.

    1980-01-01

    In order to achieve and maintain required flatness of the antenna array, a rotating laser beam used for leveling applications on earth was utilized as a reference system. A photoconductive sensor with a reflective collecting surface determines the displacement and polarity of any misalignment and automatically engages a stepping motor to drive a variable-length mechanism to make the necessary corrections. Once aligned, little power is dissipated since a nulling bridge circuit that centers on the beam is used. A three-point subarray alignment arrangement is described which independently adjusts, in the three orthogonal directions, the height and tilt of subarrays within the MPTS array and readily adapts to any physical distortions of the secondary structure (such as that resulting from severe temperature extremes caused by an eclipse of the Sun). It is shown that only one rotating laser system is required since optical blockage is minimal on the array surface and that it is possible to incorporate a number of redundant laser systems for reliability without affecting the overall performance.

  17. Modulation error in active-aperture phased-array radar systems

    NASA Astrophysics Data System (ADS)

    Belcher, M. L.; Howard, R. L.; Mitchell, M. A.

    Range sidelobe (RSL) suppression is presently treated in the context of active arrays that are defined by a phased-array antenna, which is driven by either distributed solid-state element-level modules or tube-driven subarray-level transmitters and receivers. An account is given of the basic methodology for achievement of low-RSL performance in active arrays, using modulation-error compensation. Attention is given to the performance limits imposed by modulation-error decorrelation and noise-limited error characterization.

  18. Active Vector Separation Using Induced Charge Electro-osmosis with Polarizable Obstacle Arrays

    NASA Astrophysics Data System (ADS)

    Sugioka, Hideyuki

    2016-09-01

    Vector separation using obstacle post arrays is promising for various microfluidic applications. Here, we propose a novel active sieve using induced charge electro-osmosis (ICEO). By the multi-physics simulation technique based on the boundary element method combined with a thin electric double-layer approximation, we find that the active sieve having a polarizable post array shows excellent vector separation with dynamic size selectivity owing to the hydrodynamic interactions between the polarizable post array and the target particle. We consider that our separation device is useful for realizing innovative high-throughput biomedical systems with a simple structure.

  19. RoboResource Technology Learning Activities.

    ERIC Educational Resources Information Center

    Keck, Tom, Comp.; Frye, Ellen, Ed.

    Preparing students to be successful in a rapidly changing world means showing them how to use the tools of technology and how to integrate those tools into all areas of learning. This booklet is divided into three sections: Design Activities, Experiments, and Resources. The design activities ask students to collaborate on design projects. In these…

  20. Photovoltaic solar array technology required for three wide scale generating systems for terrestrial applications: rooftop, solar farm, and satellite

    NASA Technical Reports Server (NTRS)

    Berman, P. A.

    1972-01-01

    Three major options for wide-scale generation of photovoltaic energy for terrestrial use are considered: (1) rooftop array, (2) solar farm, and (3) satellite station. The rooftop array would use solar cell arrays on the roofs of residential or commercial buildings; the solar farm would consist of large ground-based arrays, probably in arid areas with high insolation; and the satellite station would consist of an orbiting solar array, many square kilometers in area. The technology advancement requirements necessary for each option are discussed, including cost reduction of solar cells and arrays, weight reduction, resistance to environmental factors, reliability, and fabrication capability, including the availability of raw materials. The majority of the technology advancement requirements are applicable to all three options, making possible a flexible basic approach regardless of the options that may eventually be chosen. No conclusions are drawn as to which option is most advantageous, since the feasibility of each option depends on the success achieved in the technology advancement requirements specified.

  1. Diversity Array Technology Markers: Genetic Diversity Analyses and Linkage Map Construction in Rapeseed (Brassica napus L.)

    PubMed Central

    Raman, Harsh; Raman, Rosy; Nelson, Matthew N.; Aslam, M.N.; Rajasekaran, Ravikesavan; Wratten, Neil; Cowling, Wallace A.; Kilian, A.; Sharpe, Andrew G.; Schondelmaier, Joerg

    2012-01-01

    We developed Diversity Array Technology (DArT) markers for application in genetic studies of Brassica napus and other Brassica species with A or C genomes. Genomic representation from 107 diverse genotypes of B. napus L. var. oleifera (rapeseed, AACC genomes) and B. rapa (AA genome) was used to develop a DArT array comprising 11 520 clones generated using PstI/BanII and PstI/BstN1 complexity reduction methods. In total, 1547 polymorphic DArT markers of high technical quality were identified and used to assess molecular diversity among 89 accessions of B. napus, B. rapa, B. juncea, and B. carinata collected from different parts of the world. Hierarchical cluster and principal component analyses based on genetic distance matrices identified distinct populations clustering mainly according to their origin/pedigrees. DArT markers were also mapped in a new doubled haploid population comprising 131 lines from a cross between spring rapeseed lines ‘Lynx-037DH’ and ‘Monty-028DH’. Linkage groups were assigned on the basis of previously mapped simple sequence repeat (SSRs), intron polymorphism (IP), and gene-based markers. The map consisted of 437 DArT, 135 SSR, 6 IP, and 6 gene-based markers and spanned 2288 cM. Our results demonstrate that DArT markers are suitable for genetic diversity analysis and linkage map construction in rapeseed. PMID:22193366

  2. Diversity array technology markers: genetic diversity analyses and linkage map construction in rapeseed (Brassica napus L.).

    PubMed

    Raman, Harsh; Raman, Rosy; Nelson, Matthew N; Aslam, M N; Rajasekaran, Ravikesavan; Wratten, Neil; Cowling, Wallace A; Kilian, A; Sharpe, Andrew G; Schondelmaier, Joerg

    2012-01-01

    We developed Diversity Array Technology (DArT) markers for application in genetic studies of Brassica napus and other Brassica species with A or C genomes. Genomic representation from 107 diverse genotypes of B. napus L. var. oleifera (rapeseed, AACC genomes) and B. rapa (AA genome) was used to develop a DArT array comprising 11 520 clones generated using PstI/BanII and PstI/BstN1 complexity reduction methods. In total, 1547 polymorphic DArT markers of high technical quality were identified and used to assess molecular diversity among 89 accessions of B. napus, B. rapa, B. juncea, and B. carinata collected from different parts of the world. Hierarchical cluster and principal component analyses based on genetic distance matrices identified distinct populations clustering mainly according to their origin/pedigrees. DArT markers were also mapped in a new doubled haploid population comprising 131 lines from a cross between spring rapeseed lines 'Lynx-037DH' and 'Monty-028DH'. Linkage groups were assigned on the basis of previously mapped simple sequence repeat (SSRs), intron polymorphism (IP), and gene-based markers. The map consisted of 437 DArT, 135 SSR, 6 IP, and 6 gene-based markers and spanned 2288 cM. Our results demonstrate that DArT markers are suitable for genetic diversity analysis and linkage map construction in rapeseed.

  3. Advantages of Array-Based Technologies for Pre-Emptive Pharmacogenomics Testing

    PubMed Central

    Shahandeh, Al; Johnstone, Daniel M.; Atkins, Joshua R.; Sontag, Jean-Marie; Heidari, Moones; Daneshi, Nilofar; Freeman-Acquah, Elvis; Milward, Elizabeth A.

    2016-01-01

    As recognised by the National Institutes of Health (NIH) Precision Medicine Initiative (PMI), microarray technology currently provides a rapid, inexpensive means of identifying large numbers of known genomic variants or gene transcripts in experimental and clinical settings. However new generation sequencing techniques are now being introduced in many clinical genetic contexts, particularly where novel mutations are involved. While these methods can be valuable for screening a restricted set of genes for known or novel mutations, implementation of whole genome sequencing in clinical practice continues to present challenges. Even very accurate high-throughput methods with small error rates can generate large numbers of false negative or false positive errors due to the high numbers of simultaneous readings. Additional validation is likely to be required for safe use of any such methods in clinical settings. Custom-designed arrays can offer advantages for screening for common, known mutations and, in this context, may currently be better suited for accredited, quality-controlled clinical genetic screening services, as illustrated by their successful application in several large-scale pre-emptive pharmacogenomics programs now underway. Excessive, inappropriate use of next-generation sequencing may waste scarce research funds and other resources. Microarrays presently remain the technology of choice in applications that require fast, cost-effective genome-wide screening of variants of known importance, particularly for large sample sizes. This commentary considers some of the applications where microarrays continue to offer advantages over next-generation sequencing technologies. PMID:27600079

  4. Advanced Solar Cell and Array Technology for NASA Deep Space Missions

    NASA Technical Reports Server (NTRS)

    Piszczor, Michael; Benson, Scott; Scheiman, David; Finacannon, Homer; Oleson, Steve; Landis, Geoffrey

    2008-01-01

    A recent study by the NASA Glenn Research Center assessed the feasibility of using photovoltaics (PV) to power spacecraft for outer planetary, deep space missions. While the majority of spacecraft have relied on photovoltaics for primary power, the drastic reduction in solar intensity as the spacecraft moves farther from the sun has either limited the power available (severely curtailing scientific operations) or necessitated the use of nuclear systems. A desire by NASA and the scientific community to explore various bodies in the outer solar system and conduct "long-term" operations using using smaller, "lower-cost" spacecraft has renewed interest in exploring the feasibility of using photovoltaics for to Jupiter, Saturn and beyond. With recent advances in solar cell performance and continuing development in lightweight, high power solar array technology, the study determined that photovoltaics is indeed a viable option for many of these missions.

  5. Gene editing activity on extrachromosomal arrays in C. elegans transgenics.

    PubMed

    Falgowski, Kerry A; Kmiec, Eric B

    2011-04-15

    Gene editing by modified single-stranded oligonucleotides is a strategy aimed at inducing single base changes into the genome, generating a permanent genetic change. The work presented here explores gene editing capabilities in the model organism Caenorhabditis elegans. Current approaches to gene mutagenesis in C. elegans have been plagued by non-specificity and thus the ability to induce precise, directed alterations within the genome of C. elegans would offer a platform upon which structure/function analyses can be carried out. As such, several in vivo assay systems were developed to evaluate gene editing capabilities in C. elegans. Fluorescence was chosen as the selectable endpoint as fluorescence can be easily detected through the transparent worm body even from minimal expression. Two tissue specific fluorescent expression vectors containing either a GFP or mCherry transgene were mutagenized to create a single nonsense mutation within the open reading frame of each respective fluorescent gene. These served as the target site to evaluate the frequency of gene editing on extrachromosomal array transgenic lines. Extrachromosomal arrays can carry hundreds of copies of the transgene, therefore low frequency events (like those in the gene editing reaction) may be detected. Delivery of the oligonucleotide was accomplished by microinjection into the gonads of young adult worms in an effort to induce repair of the mutated fluorescent gene in the F1 progeny. Despite many microinjections on the transgenic strains with varying concentrations of ODNs, no gene editing events were detected. This result is consistent with the previous research, demonstrating the difficulties encountered in targeting embryonic stem cells and the pronuclei of single-celled embryos.

  6. Design of a Synthetic Aperture Array to Support Experiments in Active Control of Scattering

    DTIC Science & Technology

    1990-06-01

    IIC FILE COPY DESIGN OF A SYNTHETIC APERTURE ARRAY TO SUPPORT EXPERIMENTS IN ACTIVE CONTROL OF SCATTERING by JAMES P. DULLEA B.N.E. GEORGIA...Ain Sonin Clmairnnn, Mechancal Engineering Departmenlal Graduate Committee 90 09 24 053 DESIGN OF A SYNTHETIC APERTURE ARRAY TO SUPPORT EXPERIMENTS IN...partial fulfillment of the requirements for the Degrees of Naval Engineer and Master of Science in Mechanical Engineering Abstract A synthetic aperture

  7. Use of Field Programmable Gate Array Technology in Future Space Avionics

    NASA Technical Reports Server (NTRS)

    Ferguson, Roscoe C.; Tate, Robert

    2005-01-01

    Fulfilling NASA's new vision for space exploration requires the development of sustainable, flexible and fault tolerant spacecraft control systems. The traditional development paradigm consists of the purchase or fabrication of hardware boards with fixed processor and/or Digital Signal Processing (DSP) components interconnected via a standardized bus system. This is followed by the purchase and/or development of software. This paradigm has several disadvantages for the development of systems to support NASA's new vision. Building a system to be fault tolerant increases the complexity and decreases the performance of included software. Standard bus design and conventional implementation produces natural bottlenecks. Configuring hardware components in systems containing common processors and DSPs is difficult initially and expensive or impossible to change later. The existence of Hardware Description Languages (HDLs), the recent increase in performance, density and radiation tolerance of Field Programmable Gate Arrays (FPGAs), and Intellectual Property (IP) Cores provides the technology for reprogrammable Systems on a Chip (SOC). This technology supports a paradigm better suited for NASA's vision. Hardware and software production are melded for more effective development; they can both evolve together over time. Designers incorporating this technology into future avionics can benefit from its flexibility. Systems can be designed with improved fault isolation and tolerance using hardware instead of software. Also, these designs can be protected from obsolescence problems where maintenance is compromised via component and vendor availability.To investigate the flexibility of this technology, the core of the Central Processing Unit and Input/Output Processor of the Space Shuttle AP101S Computer were prototyped in Verilog HDL and synthesized into an Altera Stratix FPGA.

  8. NASA's Microgravity Technology Report: Summary of Activities 1997

    NASA Technical Reports Server (NTRS)

    Woodard, Dan

    1998-01-01

    The purpose of the 1997 NASA Microgravity Technology Report is to update the Microgravity Research Program's technology development policy and to present and assess current technology related activities and requirements identified within its research and technology disciplines.

  9. Hybrid integration technologies for a single-mode array transceiver, including the use of polymer waveguides of benzocyclobutene

    NASA Astrophysics Data System (ADS)

    Arvidsson, Gunnar; Backlin, Lennart; Olson, Magnus; Scholes, Andrew P.; Haglund, Joacim; Svensson, Magnus; Palmskog, Goran F.; Augustsson, Torsten; Eriksen, Paul; Granberg, Mats; Larsson, Jacob; Lundstrom, Pontus

    2003-03-01

    Access networks represent a bottle neck in the present communication networks. The introduction of optical single mode technology into the access networks (Fiber TO THE HOME, FTTH; Fiber To The Antenna, FTTA etc.), would be highly desirable. In order for this to occur a drastic reduction of the cost for key optoelectronic components such as transceivers is needed. We report on and discuss different key technologies crucial for the production of low cost optical single mode components. In particular a technology demonstrator in the form of an array transceiver module has been designed and fabricated, thereby demonstrating the process compatibility between a number of low-cost technologies.

  10. New VCSEL technology with scalability for single mode operation and densely integrated arrays

    NASA Astrophysics Data System (ADS)

    Zhao, Guowei; Demir, Abdullah; Freisem, Sabine; Zhang, Yu; Liu, Xiaohang; Deppe, Dennis G.

    2011-06-01

    Data are presented demonstrating a new lithographic vertical-cavity surface-emitting laser (VCSEL) technology, which produces simultaneous mode- and current-confinement only by lithography and epitaxial crystal growth. The devices are grown by solid source molecular beam epitaxy, and have lithographically defined sizes that vary from 3 μm to 20 μm. The lithographic process allows the devices to have high uniformity throughout the wafer and scalability to very small size. The 3 μm device shows a threshold current of 310 μA, the slope efficiency of 0.81 W/A, and the maximum output power of more than 5 mW. The 3 μm device also shows single-mode single-polarization operation without the use of surface grating, and has over 25 dB side-mode-suppression-ratio up to 1 mW of output power. The devices have low thermal resistance due to the elimination of oxide aperture. High reliability is achieved by removal of internal strain caused by the oxide, stress test shows no degradation for the 3 μm device operating at very high injection current level of 142 kA/cm2 for 1000 hours, while at this dive level commercial VCSELs fail rapidly. The lithographic VCSEL technology can lead to manufacture of reliable small size laser diode, which will have application in large area 2-D arrays and low power sensors.

  11. High-throughput genotyping of hop (Humulus lupulus L.) utilising diversity arrays technology (DArT).

    PubMed

    Howard, E L; Whittock, S P; Jakše, J; Carling, J; Matthews, P D; Probasco, G; Henning, J A; Darby, P; Cerenak, A; Javornik, B; Kilian, A; Koutoulis, A

    2011-05-01

    Implementation of molecular methods in hop (Humulus lupulus L.) breeding is dependent on the availability of sizeable numbers of polymorphic markers and a comprehensive understanding of genetic variation. However, use of molecular marker technology is limited due to expense, time inefficiency, laborious methodology and dependence on DNA sequence information. Diversity arrays technology (DArT) is a high-throughput cost-effective method for the discovery of large numbers of quality polymorphic markers without reliance on DNA sequence information. This study is the first to utilise DArT for hop genotyping, identifying 730 polymorphic markers from 92 hop accessions. The marker quality was high and similar to the quality of DArT markers previously generated for other species; although percentage polymorphism and polymorphism information content (PIC) were lower than in previous studies deploying other marker systems in hop. Genetic relationships in hop illustrated by DArT in this study coincide with knowledge generated using alternate methods. Several statistical analyses separated the hop accessions into genetically differentiated North American and European groupings, with hybrids between the two groups clearly distinguishable. Levels of genetic diversity were similar in the North American and European groups, but higher in the hybrid group. The markers produced from this time and cost-efficient genotyping tool will be a valuable resource for numerous applications in hop breeding and genetics studies, such as mapping, marker-assisted selection, genetic identity testing, guidance in the maintenance of genetic diversity and the directed breeding of superior cultivars.

  12. Preparation of electrochemically active silicon nanotubes in highly ordered arrays.

    PubMed

    Grünzel, Tobias; Lee, Young Joo; Kuepper, Karsten; Bachmann, Julien

    2013-01-01

    Silicon as the negative electrode material of lithium ion batteries has a very large capacity, the exploitation of which is impeded by the volume changes taking place upon electrochemical cycling. A Si electrode displaying a controlled porosity could circumvent the difficulty. In this perspective, we present a preparative method that yields ordered arrays of electrochemically competent silicon nanotubes. The method is based on the atomic layer deposition of silicon dioxide onto the pore walls of an anodic alumina template, followed by a thermal reduction with lithium vapor. This thermal reduction is quantitative, homogeneous over macroscopic samples, and it yields amorphous silicon and lithium oxide, at the exclusion of any lithium silicides. The reaction is characterized by spectroscopic ellipsometry for thin silica films, and by nuclear magnetic resonance and X-ray photoelectron spectroscopy for nanoporous samples. After removal of the lithium oxide byproduct, the silicon nanotubes can be contacted electrically. In a lithium ion electrolyte, they then display the electrochemical waves also observed for other bulk or nanostructured silicon systems. The method established here paves the way for systematic investigations of how the electrochemical properties (capacity, charge/discharge rates, cyclability) of nanoporous silicon negative lithium ion battery electrode materials depend on the geometry.

  13. Templated electrodeposition and photocatalytic activity of cuprous oxide nanorod arrays.

    PubMed

    Haynes, Keith M; Perry, Collin M; Rivas, Marlene; Golden, Teresa D; Bazan, Antony; Quintana, Maria; Nesterov, Vladimir N; Berhe, Seare A; Rodríguez, Juan; Estrada, Walter; Youngblood, W Justin

    2015-01-14

    Cuprous oxide (Cu2O) nanorod arrays have been prepared via a novel templated electrodeposition process and were characterized for their photocatalytic behavior in nonaqueous photoelectrochemical cells. Zinc oxide (ZnO) nanorod films serve as sacrificial templates for the in situ formation of polymer nanopore membranes on transparent conductive oxide substrates. Nitrocellulose and poly(lactic acid) are effective membrane-forming polymers that exhibit different modes of template formation, with nitrocellulose forming conformal coatings on the ZnO surface while poly(lactic acid) acts as an amorphous pore-filling material. Robust template formation is sensitive to the seeding method used to prepare the precursor ZnO nanorod films. Photoelectrochemical cells prepared from electrodeposited Cu2O films using methyl viologen as a redox shuttle in acetonitrile electrolyte exhibit significant charge recombination that can be partially suppressed by a combination of surface passivation methods. Surface-passivated nanostructured Cu2O films show enhanced photocurrent relative to planar electrodeposited Cu2O films of similar thickness. We have obtained the highest photocurrent ever reported for electrodeposited Cu2O in a nonaqueous photoelectrochemical cell.

  14. Applying Ultrasonic Phased Array Technology to Examine Austenitic Coarse-Grained Structures for Light Water Reactor Piping

    SciTech Connect

    Anderson, Michael T.; Cumblidge, Stephen E.; Doctor, Steven R.

    2003-12-18

    Pacific Northwest Laboratory is evaluating the capabilities and limitations of phased array (PA) technology to detect service-type flaws in coarse-grained austenitic piping structures. The work is being sponsored by the U.S. Nuclear Regulatory Commission, Office of Research. This paper presents initial work involving the use of PA technology to determine the effectiveness of detecting and accurately characterizing flaws on the far-side of austenitic piping welds.

  15. Fabrication and photocatalytic activities of ZnO arrays with different nanostructures

    NASA Astrophysics Data System (ADS)

    Sun, Fazhe; Qiao, Xueliang; Tan, Fatang; Wang, Wei; Qiu, Xiaolin

    2012-12-01

    Large-scale ZnO arrays with a series of morphologies, including nest-like, tower-like, and flower-like samples, have been successfully synthesized by a simple hydrothermal method. The morphologies of the obtained ZnO arrays can be conveniently tailored by changing seeding conditions. The samples were characterized using X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and photoluminescence (PL) spectroscopy. Their PL spectra depend on their morphologies and defects density. The morphology-dependent photocatalytic performances were studied by analyzing the degradation of methylene blue (MB) in aqueous solution. The nest-like ZnO arrays exhibited higher photocatalytic activity than tower-like and flower-like ZnO arrays.

  16. Antibacterial activity of single crystalline silver-doped anatase TiO2 nanowire arrays

    NASA Astrophysics Data System (ADS)

    Zhang, Xiangyu; Li, Meng; He, Xiaojing; Hang, Ruiqiang; Huang, Xiaobo; Wang, Yueyue; Yao, Xiaohong; Tang, Bin

    2016-05-01

    Well-ordered, one-dimensional silver-doped anatase TiO2 nanowire (AgNW) arrays have been prepared through a hydrothermal growth process on the sputtering-deposited AgTi layers. Electron microscope analyses reveal that the as-synthesized AgNW arrays exhibit a single crystalline phase with highly uniform morphologies, diameters ranging from 85 to 95 nm, and lengths of about 11 μm. Silver is found to be doped into TiO2 nanowire evenly and mainly exists in the zerovalent state. The AgNW arrays show excellent efficient antibacterial activity against Escherichia coli (E. coli), and all of the bacteria can be killed within 1 h. Additionally, the AgNW arrays can still kill E. coli after immersion for 60 days, suggesting the long-term antibacterial property. The technique reported here is environmental friendly for formation of silver-containing nanostructure without using any toxic organic solvents.

  17. High Density Individually Addressable Nanowire Arrays Record Intracellular Activity from Primary Rodent and Human Stem Cell Derived Neurons.

    PubMed

    Liu, Ren; Chen, Renjie; Elthakeb, Ahmed T; Lee, Sang Heon; Hinckley, Sandy; Khraiche, Massoud L; Scott, John; Pre, Deborah; Hwang, Yoontae; Tanaka, Atsunori; Ro, Yun Goo; Matsushita, Albert K; Dai, Xing; Soci, Cesare; Biesmans, Steven; James, Anthony; Nogan, John; Jungjohann, Katherine L; Pete, Douglas V; Webb, Denise B; Zou, Yimin; Bang, Anne G; Dayeh, Shadi A

    2017-04-10

    We report a new hybrid integration scheme that offers for the first time a nanowire-on-lead approach, which enables independent electrical addressability, is scalable, and has superior spatial resolution in vertical nanowire arrays. The fabrication of these nanowire arrays is demonstrated to be scalable down to submicrometer site-to-site spacing and can be combined with standard integrated circuit fabrication technologies. We utilize these arrays to perform electrophysiological recordings from mouse and rat primary neurons and human induced pluripotent stem cell (hiPSC)-derived neurons, which revealed high signal-to-noise ratios and sensitivity to subthreshold postsynaptic potentials (PSPs). We measured electrical activity from rodent neurons from 8 days in vitro (DIV) to 14 DIV and from hiPSC-derived neurons at 6 weeks in vitro post culture with signal amplitudes up to 99 mV. Overall, our platform paves the way for longitudinal electrophysiological experiments on synaptic activity in human iPSC based disease models of neuronal networks, critical for understanding the mechanisms of neurological diseases and for developing drugs to treat them.

  18. Technology and Engineering Advances Supporting EarthScope's Alaska Transportable Array

    NASA Astrophysics Data System (ADS)

    Miner, J.; Enders, M.; Busby, R.

    2015-12-01

    EarthScope's Transportable Array (TA) in Alaska and Canada is an ongoing deployment of 261 high quality broadband seismographs. The Alaska TA is the continuation of the rolling TA/USArray deployment of 400 broadband seismographs in the lower 48 contiguous states and builds on the success of the TA project there. The TA in Alaska and Canada is operated by the IRIS Consortium on behalf of the National Science Foundation as part of the EarthScope program. By Sept 2015, it is anticipated that the TA network in Alaska and Canada will be operating 105 stations. During the summer of 2015, TA field crews comprised of IRIS and HTSI station specialists, as well as representatives from our partner agencies the Alaska Earthquake Center and the Alaska Volcano Observatory and engineers from the UNAVCO Plate Boundary Observatory will have completed a total of 36 new station installations. Additionally, we will have completed upgrades at 9 existing Alaska Earthquake Center stations with borehole seismometers and the adoption of an additional 35 existing stations. Continued development of battery systems using LiFePO4 chemistries, integration of BGAN, Iridium, Cellular and VSAT technologies for real time data transfer, and modifications to electronic systems are a driving force for year two of the Alaska Transportable Array. Station deployment utilizes custom heliportable drills for sensor emplacement in remote regions. The autonomous station design evolution include hardening the sites for Arctic, sub-Arctic and Alpine conditions as well as the integration of rechargeable Lithium Iron Phosphate batteries with traditional AGM batteries We will present new design aspects, outcomes, and lessons learned from past and ongoing deployments, as well as efforts to integrate TA stations with other existing networks in Alaska including the Plate Boundary Observatory and the Alaska Volcano Observatory.

  19. A High Aspect Ratio Microelectrode Array for Mapping Neural Activity in-vitro

    PubMed Central

    Kibler, Andrew B.; Jamieson, Brian G.; Durand, Dominique M.

    2011-01-01

    A novel high-aspect-ratio penetrating microelectrode array was designed and fabricated for the purpose of recording neural activity. The array allows two dimensional recording of 64 sites in vitro with high aspect ratio penetrating electrodes. Traditional surface electrode arrays, although easy to fabricate, do not penetrate to the viable tissue such as central hippocampus slices and thus have a lower signal/noise ratio and lower selectivity than a penetrating array. In the unfolded hippocampus preparation, the CA1–CA3 pyramidal cell layer in the whole unfolded rodent hippocampus preparation is encased by the alveus on one side and the Schaffer tract on the other and requires penetrating electrodes for high signal to noise ratio recording. An array of 64 electrode spikes, each with a target height of 200 μm and diameter of 20μm, was fabricated in silicon on a transparent glass substrate. The impedance of the individual electrodes was measured to be approximately 1.5MΩ± 497kΩ. The signal to noise ratio was measured and found to be 19.4 ± 3 dB compared to 3.9 ± 0.8 dB S/N for signals obtained with voltage sensitive dye RH414. A mouse unfolded hippocampus preparation was bathed in solution containing 50 micro-molar 4-Amino Pyridine and a complex two dimensional wave of activity was recorded using the array. These results indicate that this novel penetrating electrode array is able to obtain data superior to that of voltage sensitive dye techniques for broad field two-dimensional neuronal activity recording. When used with the unfolded hippocampus preparation, the combination forms a uniquely capable tool for imaging hippocampal network activity in the entire hippocampus. PMID:22179041

  20. Thin-film transistor array technology for high-performance direct-conversion x-ray sensors

    NASA Astrophysics Data System (ADS)

    den Boer, Willem; Aggas, Steven; Byun, Young H.; Gu, Tieer; Zhong, Johnny Q.; Thomsen, Scott V.; Jeromin, Lothar S.; Lee, Denny L. Y.

    1998-07-01

    Thin Film Transistor (TFT) array technology is presented for Digital X-ray Sensors in Direct Radiography applications. Circuit simulations were performed to optimize the design of the TFT array. The sensor array uses a combination of a mushroom electrode with a high fill factor of 86% and a polymer passivation dielectric to minimize column capacitance and improve signal-to-noise ratio. A 14 in. X 8.5 in. sensor array with 1536 X 2560 pixels was developed using this technology. The TFT arrays are processed entirely in Class 1 clean room environments to eliminate line defects and minimize pixel defects. The best 14 in. X 8.5 in. panels have exhibited fewer than 0.001% pixel defects, as detected during in process testing prior to Se coating. In typical image quality comparisons with conventional X-ray film/screen combinations, the digital X-ray sensor exhibited equal or better performance than film-screens. Clinical studies were also conducted. Radiologists concluded that diagnostically significant projection radiographic images can be produced with the new digital X-ray sensor that are equivalent or superior to conventional film/screen images at the same X-ray exposures. The detector recently received FDA approval.

  1. Breadboard linear array scan imager using LSI solid-state technology

    NASA Technical Reports Server (NTRS)

    Tracy, R. A.; Brennan, J. A.; Frankel, D. G.; Noll, R. E.

    1976-01-01

    The performance of large scale integration photodiode arrays in a linear array scan (pushbroom) breadboard was evaluated for application to multispectral remote sensing of the earth's resources. The technical approach, implementation, and test results of the program are described. Several self scanned linear array visible photodetector focal plane arrays were fabricated and evaluated in an optical bench configuration. A 1728-detector array operating in four bands (0.5 - 1.1 micrometer) was evaluated for noise, spectral response, dynamic range, crosstalk, MTF, noise equivalent irradiance, linearity, and image quality. Other results include image artifact data, temporal characteristics, radiometric accuracy, calibration experience, chip alignment, and array fabrication experience. Special studies and experimentation were included in long array fabrication and real-time image processing for low-cost ground stations, including the use of computer image processing. High quality images were produced and all objectives of the program were attained.

  2. High-density stretchable microelectrode arrays: An integrated technology platform for neural and muscular surface interfacing

    NASA Astrophysics Data System (ADS)

    Guo, Liang

    2011-12-01

    Numerous applications in neuroscience research and neural prosthetics, such as retinal prostheses, spinal-cord surface stimulation for prosthetics, electrocorticogram (ECoG) recording for epilepsy detection, etc., involve electrical interaction with soft excitable tissues using a surface stimulation and/or recording approach. These applications require an interface that is able to set up electrical communications with a high throughput between electronics and the excitable tissue and that can dynamically conform to the shape of the soft tissue. Being a compliant and biocompatible material with mechanical impedance close to that of soft tissues, polydimethylsiloxane (PDMS) offers excellent potential as the substrate material for such neural interfaces. However, fabrication of electrical functionalities on PDMS has long been very challenging. This thesis work has successfully overcome many challenges associated with PDMS-based microfabrication and achieved an integrated technology platform for PDMS-based stretchable microelectrode arrays (sMEAs). This platform features a set of technological advances: (1) we have fabricated uniform current density profile microelectrodes as small as 10 mum in diameter; (2) we have patterned high-resolution (feature as small as 10 mum), high-density (pitch as small as 20 mum) thin-film gold interconnects on PDMS substrate; (3) we have developed a multilayer wiring interconnect technology within the PDMS substrate to further boost the achievable integration density of such sMEA; and (4) we have invented a bonding technology---via-bonding---to facilitate high-resolution, high-density integration of the sMEA with integrated circuits (ICs) to form a compact implant. Taken together, this platform provides a high-resolution, high-density integrated system solution for neural and muscular surface interfacing. sMEAs of example designs are evaluated through in vitro and in vivo experimentations on their biocompatibility, surface conformability

  3. Development and assessment of Diversity Arrays Technology for high-throughput DNA analyses in Musa.

    PubMed

    Risterucci, Ange-Marie; Hippolyte, Isabelle; Perrier, Xavier; Xia, Ling; Caig, Vanessa; Evers, Margaret; Huttner, Eric; Kilian, Andrzej; Glaszmann, Jean-Christophe

    2009-10-01

    Diversity Arrays Technology (DArT) is a DNA hybridisation-based molecular marker technique that can detect simultaneously variation at numerous genomic loci without sequence information. This efficiency makes it a potential tool for a quick and powerful assessment of the structure of germplasm collections. This article demonstrates the usefulness of DArT markers for genetic diversity analyses of Musa spp. genotypes. We developed four complexity reduction methods to generate DArT genomic representations and we tested their performance using 48 reference Musa genotypes. For these four complexity reduction methods, DArT markers displayed high polymorphism information content. We selected the two methods which generated the most polymorphic genomic representations (PstI/BstNI 16.8%, PstI/TaqI 16.1%) to analyze a panel of 168 Musa genotypes from two of the most important field collections of Musa in the world: Cirad (Neufchateau, Guadeloupe), and IITA (Ibadan, Nigeria). Since most edible cultivars are derived from two wild species, Musa acuminata (A genome) and Musa balbisiana (B genome), the study is restricted mostly to accessions of these two species and those derived from them. The genomic origin of the markers can help resolving the pedigree of valuable genotypes of unknown origin. A total of 836 markers were identified and used for genotyping. Ten percent of them were specific to the A genome and enabled targeting this genome portion in relatedness analysis among diverse ploidy constitutions. DArT markers revealed genetic relationships among Musa genotype consistent with those provided by the other markers technologies, but at a significantly higher resolution and speed and reduced cost.

  4. The microcantilever array: a low-power, compact, and sensitive unattended sensor technology

    NASA Astrophysics Data System (ADS)

    Rogers, B.; Whitten, R.; Adams, J. D.

    2005-10-01

    In an unattended, implanted or mobile ground sensor scenario, the microcantilever platform is well suited: sensor power consumption has been demonstrated at the nanowatt level and, as a microelectromechanical system, the platform is inherently compact. In addition, the remarkable sensitivity, low cost, scalability, durability and versatility of microcantilever sensors make this technology among the most promising solutions for unattended ground sensing of chemical and biological agents, as well as explosives. Nevada Nanotech Systems, Inc (NNTS) is developing a microcantilever- based detection system that will measure trace concentrations of explosives, toxic chemicals, and biological agents in air. A baseline sensor unit that includes the sensor array, electronics, power supply and air handling has been designed and preliminary demonstrations of the microcantilever platform have been conducted. The envisioned device would measure about two cubic inches, run on a small watch battery and cost a few hundred dollars. Finally, the NNTS microcantilever sensor has potential as a multifunctional transducer for enhancing detection and discrimination. Recent test results using this platform will be discussed.

  5. Technology for fabrication of sub-20 nm silicon planar nanowires array

    NASA Astrophysics Data System (ADS)

    Miakonkikh, Andrey V.; Tatarintsev, Andrey A.; Rogozhin, Alexander E.; Rudenko, Konstantin V.

    2016-12-01

    The results presented on Silicon one-dimensional structures fabrication which are promising for application in nanoelectronics, sensors, THz-applications. We employ two-stage technology of precise anizotropic plasma etching of silicon over e-beam resist and isotropic removal of thermally oxidised defected surface layer of silicon by wet etch. As first the process for nano-fins fabrication on SOI substrate was developed. HSQ resist was used as a negative-tone electron beam resist with good etch-resistance, high resolution and high mechanical stability. The etching was performed by RIE in mix of SF6 + C4F8. plasma. By changing the ratio SF6:C4F8, the sidewall profile angle can be controlled thoroughly. Next step to minimize lateral size of structures and reduce impact of surface defects on electron mobility in core of nanowires was the application of surface thermal oxidation to defected layer. It was used for selective removal of damaged silicon layer and polymer residues. Oxidation was performed with controlled flow of dry oxygen and water vapour. Oxidation rate was precisely controlled by ex-situ spectral ellipsometry on unpatterned chips As a result the arrays of planar sub-20 nm Silicon nanowires with length in the range 200 nm - 500 um were made.

  6. Expression of chondrogenic genes by undifferentiated vs. differentiated human mesenchymal stem cells using array technology.

    PubMed

    Henrionnet, Christel; Roeder, Emilie; Gillet, Romain; Galois, Laurent; Bensoussan, Danièle; Mainard, Didier; Netter, Patrick; Gillet, Pierre; Pinzano, Astrid

    2010-01-01

    This study investigated the gene expression profile of human mesenchymal stem cells seeded in collagen sponge for 28 days in three different mediums: (1) basal medium as control containing ITS alone, (2) ITS+TGF-β1 alone or (3) ITS 1% supplemented sequentially by TGF-β1 (D3-D14) followed by BMP-2 (D15-D28). Differential expression of 84 genes implicated in chondrogenic and osteogenic differentiation of MSCs was analyzed at D28 by real-time RT-PCR array technology. TGF-β1 alone down-regulated two genes, CD36 and cathepsin K. Sixteen genes were significantly up-regulated, notably type 2 and type 10 collagens, COMP and Sox9. The sequential combination of TGF-β1 and BMP-2 produced a similar profile with prominent expression of type 2 collagen and the alkaline phosphatase gene. Interestingly, in this in vitro condition, RUNX2 was not up-regulated, suggesting that the sequential combination of TGF-β1/BMP2 enhances the hypertrophic chondrogenic profile without turning towards the osteoblastic pathway.

  7. Phased array feed design technology for Large Aperture Microwave Radiometer (LAMR) Earth observations

    NASA Technical Reports Server (NTRS)

    Schuman, H. K.

    1992-01-01

    An assessment of the potential and limitations of phased array antennas in space-based geophysical precision radiometry is described. Mathematical models exhibiting the dependence of system and scene temperatures and system sensitivity on phased array antenna parameters and components such as phase shifters and low noise amplifiers (LNA) are developed. Emphasis is given to minimum noise temperature designs wherein the LNA's are located at the array level, one per element or subarray. Two types of combiners are considered: array lenses (space feeds) and corporate networks. The result of a survey of suitable components and devices is described. The data obtained from that survey are used in conjunction with the mathematical models to yield an assessment of effective array antenna noise temperature for representative geostationary and low Earth orbit systems. Practical methods of calibrating a space-based, phased array radiometer are briefly addressed as well.

  8. Electrodeposition of gold nanoparticle arrays on ITO glass as electrode with high electrocatalytic activity

    SciTech Connect

    Zhang, Kui; Wei, Juan; Zhu, Houjuan; Ma, Fang; Wang, Suhua

    2013-03-15

    Highlights: ► Electrodeposition of gold nanoparticle arrays on ITO glass as catalytic-electrodes. ► The sizes and densities of the gold nanoparticles can be easily controlled. ► Such arrays on ITO glass shows high electrocatalytic activity and good stability. - Abstract: Herein, we reported a templateless, surfactantless, and simple electrochemical method to directly fabricate gold nanoparticle (AuNP) arrays on indium tin oxide (ITO) glass substrates as effective electrocatalytic electrodes. The as-prepared AuNP arrays have been characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), etc. AuNPs with small sizes (<20 nm) were uniformly deposited on the ITO glass under constant current densities, and particle densities can be adjusted by varying the applied charges. The resultant AuNP array electrode showed higher catalytic activity and good stability toward electro-oxidation of ascorbic acid compared with other electrodes, such as bare ITO electrode, bare glassy carbon electrode and bulk gold film electrode.

  9. Guidance manual for conducting technology demonstration activities

    SciTech Connect

    Jolley, Robert L.; Morris, Michael I.; Singh, Suman P.N.

    1991-12-01

    This demonstration guidance manual has been prepared to assist Martin Marietta Energy Systems, Inc. (Energy Systems), staff in conducting demonstrations. It is prepared in checklist style to facilitate its use and assumes that Energy Systems personnel have project management responsibility. In addition to a detailed step-by-step listing of procedural considerations, a general checklist, logic flow diagram, and several examples of necessary plans are included to assist the user in developing an understanding of the many complex activities required to manage technology demonstrations. Demonstrations are pilot-scale applications of often innovative technologies to determine the commercial viability of the technologies to perform their designed function. Demonstrations are generally conducted on well-defined problems for which existing technologies or processes are less than satisfactory in terms of effectiveness, cost, and/or regulatory compliance. Critically important issues in demonstration management include, but are not limited to, such factors as communications with line and matrix management and with the US Department of Energy (DOE) and Energy Systems staff responsible for management oversight, budgetary and schedule requirements, regulatory compliance, and safety.

  10. Study of solar array switching power management technology for space power system

    NASA Technical Reports Server (NTRS)

    Cassinelli, J. E.

    1982-01-01

    This report documents work performed on the Solar Array Switching Power Management Study. Mission characteristics for three missions were defined to the depth necessary to determine their power management requirements. Solar array switching concepts were identified that could safisfy the mission requirements. These switching concepts were compared with a conventional buck regulator system on the basis of cost, weight and volume, reliability, efficiency and thermal control. For the missions reviewed, solar array switching provided significant advantages in all areas of comparison.

  11. Study of solar array switching power management technology for space power system

    NASA Technical Reports Server (NTRS)

    Cassinelli, J. E.

    1982-01-01

    This report documents work performed on the Solar Array Switching Power Management Study. Mission characteristics for three missions were defined to the depth necessary to determine their power management requirements. Solar array switching concepts which could satisfy the mission requirements were identified. The switching concepts were compared with a conventional buck regulator system for cost, weight and volume, reliability, efficiency and thermal control. Solar array switching provided significant advantages in all areas of comparison for the reviewed missions.

  12. Simultaneous multi-patch-clamp and extracellular-array recordings: Single neuron reflects network activity

    NASA Astrophysics Data System (ADS)

    Vardi, Roni; Goldental, Amir; Sardi, Shira; Sheinin, Anton; Kanter, Ido

    2016-11-01

    The increasing number of recording electrodes enhances the capability of capturing the network’s cooperative activity, however, using too many monitors might alter the properties of the measured neural network and induce noise. Using a technique that merges simultaneous multi-patch-clamp and multi-electrode array recordings of neural networks in-vitro, we show that the membrane potential of a single neuron is a reliable and super-sensitive probe for monitoring such cooperative activities and their detailed rhythms. Specifically, the membrane potential and the spiking activity of a single neuron are either highly correlated or highly anti-correlated with the time-dependent macroscopic activity of the entire network. This surprising observation also sheds light on the cooperative origin of neuronal burst in cultured networks. Our findings present an alternative flexible approach to the technique based on a massive tiling of networks by large-scale arrays of electrodes to monitor their activity.

  13. Simultaneous multi-patch-clamp and extracellular-array recordings: Single neuron reflects network activity

    PubMed Central

    Vardi, Roni; Goldental, Amir; Sardi, Shira; Sheinin, Anton; Kanter, Ido

    2016-01-01

    The increasing number of recording electrodes enhances the capability of capturing the network’s cooperative activity, however, using too many monitors might alter the properties of the measured neural network and induce noise. Using a technique that merges simultaneous multi-patch-clamp and multi-electrode array recordings of neural networks in-vitro, we show that the membrane potential of a single neuron is a reliable and super-sensitive probe for monitoring such cooperative activities and their detailed rhythms. Specifically, the membrane potential and the spiking activity of a single neuron are either highly correlated or highly anti-correlated with the time-dependent macroscopic activity of the entire network. This surprising observation also sheds light on the cooperative origin of neuronal burst in cultured networks. Our findings present an alternative flexible approach to the technique based on a massive tiling of networks by large-scale arrays of electrodes to monitor their activity. PMID:27824075

  14. Clinical applications of penetrating neural interfaces and Utah Electrode Array technologies

    NASA Astrophysics Data System (ADS)

    Normann, Richard A.; Fernandez, Eduardo

    2016-12-01

    This paper briefly describes some of the recent progress in the development of penetrating microelectrode arrays and highlights the use of two of these devices, Utah electrode arrays and Utah slanted electrode arrays, in two therapeutic interventions: recording volitional skeletal motor commands from the central nervous system, and recording motor commands and evoking somatosensory percepts in the peripheral nervous system (PNS). The paper also briefly explores other potential sites for microelectrode array interventions that could be profitably pursued and that could have important consequences in enhancing the quality of life of patients that has been compromised by disorders of the central and PNSs.

  15. Effects of Organophosphorus Flame Retardants on Spontaneous Activity in Neuronal Networks Grown on Microelectrode Arrays

    EPA Science Inventory

    EFFECTS OF ORGANOPHOSPHORUS FLAME RETARDANTS ON SPONTANEOUS ACTIVITY IN NEURONAL NETWORKS GROWN ON MICROELECTRODE ARRAYS TJ Shafer1, K Wallace1, WR Mundy1, M Behl2,. 1Integrated Systems Toxicology Division, NHEERL, USEPA, RTP, NC, USA, 2National Toxicology Program, NIEHS, RTP, NC...

  16. The ASTRI SST-2M prototype for the Cherenkov Telescope Array: prototype technologies goals and strategies for the future SST

    NASA Astrophysics Data System (ADS)

    Marchiori, Gianpietro; Busatta, Andrea; Giacomel, Stefano; Folla, Ivan; Valsecchi, Marco; Canestrari, Rodolfo; Bonnoli, Giacomo; Cascone, Enrico; Conconi, Paolo; Fiorini, Mauro; Giro, Enrico; La Palombara, Nicola; Pareschi, Giovanni; Perri, Luca; Rodeghiero, Gabriele; Sironi, Giorgia; Stringhetti, Luca; Toso, Giorgio; Tosti, Gino; Pellicciari, Carlo

    2014-07-01

    The Cherenkov Telescope Array (CTA) observatory will represent the next generation of Imaging Atmospheric Cherenkov Telescope. Using a combination of large-, medium-, and small-scale telescopes (LST, MST, SST, respectively), it will explore the Very High Energy domain from a few tens of GeVup to about few hundreds of TeV with unprecedented sensitivity, angular resolution and imaging quality. In this framework, the Italian ASTRI program, led by the Italian National Institute of Astrophysics (INAF) developed a 4-meter class telescope, which will adopt an aplanatic, wide-field, double-reflection optical layout in a Schwarzschild- Couder configuration. Within this program INAF assigned to the consortium between Galbiati Group and EIE Group the construction, assembly and tests activities of the prototype named ASTRI SST-2M. On the basis of the lesson learnt from the prototype, other telescopes will be produced, starting from a re-design phase, in order to optimize performances and the overall costs and production schedule for the CTA-SST telescope. This paper will firstly give an overview of the concept for the SST prototype mount structure. In this contest, the technologies adopted for the design, manufacturing and tests of the entire system will be presented. Moreover, a specific focus on the challenges of the prototype and the strategies associated with it will be provided, in order to outline the near future performance goals for this type of Cherenkov telescopes employed for Gamma ray science.

  17. A Large-N Mixed Sensor Active + Passive Seismic Array near Sweetwater, TX

    NASA Astrophysics Data System (ADS)

    Barklage, M.; Hollis, D.; Gridley, J. M.; Woodward, R.; Spriggs, N.

    2014-12-01

    A collaborative high-density seismic survey using broadband and short period seismic sensors was conducted March 7 - April 30, 2014 near Sweetwater, TX. The objective of the survey was to use a combination of controlled source shot slices and passive seismic recordings recorded by multiple types of sensors with different bandwidths and sensitivities to image the subsurface. The broadband component of the survey consisted of 25 continuously recording seismic stations comprised of 20 Trillium Compact Posthole sensors from Nanometrics and 5 Polar Trillium 120PHQs from the IRIS/PASSCAL Instrument Center (PIC). The broadband stations also utilized 25 Centaur digitizers from Nanometrics as well as 25 polar quick deploy enclosures from the PIC. The broadband array was designed to maximize horizontal traveling seismic energy for surface wave analysis over the primary target area with sufficient offset for imaging objectives at depth. The short period component of the survey consisted of 2639 receiver locations using Zland nodes from NodalSeismic. The nodes are further divided into 3 sub-arrays: 1) outlier array 2) active source array 3) backbone array. The outlier array consisted of 25 continuously recording nodes distributed around the edge of the survey at a distance of ~5 km from the survey boundary, and provided valuable constraints to passive data analysis techniques at the edge of the survey boundary. The active source patch consisted of densely spaced nodes that were designed to record signals from a Vibroseis source truck for active source reflection processing and imaging. The backbone array consisted of 292 nodes that covered the entirety of the survey area to maximize the value of the passive data analysis. By utilizing continuous recording and smartly designed arrays for measuring local and regional earthquakes we can incorporate velocity information derived from passive data analysis into the active source processing workflow to produce a superior subsurface

  18. Improving GPR Surveys Productivity by Array Technology and Fully Automated Processing

    NASA Astrophysics Data System (ADS)

    Morello, Marco; Ercoli, Emanuele; Mazzucchelli, Paolo; Cottino, Edoardo

    2016-04-01

    The realization of network infrastructures with lower environmental impact and the tendency to use digging technologies less invasive in terms of time and space of road occupation and restoration play a key-role in the development of communication networks. However, pre-existing buried utilities must be detected and located in the subsurface, to exploit the high productivity of modern digging apparatus. According to SUE quality level B+ both position and depth of subsurface utilities must be accurately estimated, demanding for 3D GPR surveys. In fact, the advantages of 3D GPR acquisitions (obtained either by multiple 2D recordings or by an antenna array) versus 2D acquisitions are well-known. Nonetheless, the amount of acquired data for such 3D acquisitions does not usually allow to complete processing and interpretation directly in field and in real-time, thus limiting the overall efficiency of the GPR acquisition. As an example, the "low impact mini-trench "technique (addressed in ITU - International Telecommunication Union - L.83 recommendation) requires that non-destructive mapping of buried services enhances its productivity to match the improvements of new digging equipment. Nowadays multi-antenna and multi-pass GPR acquisitions demand for new processing techniques that can obtain high quality subsurface images, taking full advantage of 3D data: the development of a fully automated and real-time 3D GPR processing system plays a key-role in overall optical network deployment profitability. Furthermore, currently available computing power suggests the feasibility of processing schemes that incorporate better focusing algorithms. A novel processing scheme, whose goal is the automated processing and detection of buried targets that can be applied in real-time to 3D GPR array systems, has been developed and fruitfully tested with two different GPR arrays (16 antennas, 900 MHz central frequency, and 34 antennas, 600 MHz central frequency). The proposed processing

  19. Repository Technology Program activities, FY 1988

    SciTech Connect

    Yow, J.L. Jr.; Wijesinghe, A.M.; Thorpe, R.K.; Knapp, R.B.

    1989-07-01

    Our technical activities in FY 1988 included instrument selection and evaluation, calculational work, and simulator development. Near the end of the fiscal year, we began preparing several topical reports to document our results. This fiscal year, we continued developing three-dimensional numerical simulators to model coupled hydrologic-and mechanical-rock mass responses and, thus, to provide representative numerical tools for understanding and calculating these in situ processes. We also began scoping calculations in the second half of FY 1988 to evaluate ERE design criteria, but this work was redirected late in the year when the DOE/AECL Subsidiary Agreement was set aside. Our work in developing and evaluating experimental techniques focused on total pressure measurements, moisture content measurement, and tracer detection instrumentation for sealing experiments and for rock-mass-response field tests. At the end of the fiscal year, we completed a review of measurement technology for instrumenting migration/sorption tests to help define the technological requirements in these areas. By the end of FY 1988, we had completed a review of the existing codes for simulating reactive transport; we are using the results of this review to help formulate plans for future activities in this area. The following sections describe the major RTP tasks and activities at LLNL in more detail, and they include our FY 1988 accomplishments in these areas. 8 refs., 22 figs.

  20. SERS-active nanoparticle aggregate technology for tags and seals

    SciTech Connect

    Brown, Leif O; Montoya, Velma M; Havrilla, George J; Doorn, Stephen K

    2010-06-03

    In this paper, we describe our efforts to create a modern tagging and sealing technology for international safeguards application. Our passive tagging methods are based on SANAs (SERS-Active Nanoparticle Aggregates; SERS: Surface Enhanced Raman Scattering). These SANAs offer robust spectral barcoding capability in an inexpensive tag/seal, with the possibility of rapid in-field verification that requires no human input. At INMM 2009, we introduced SANAs, and showed approaches to integrating our technology with tags under development at Sandia National Laboratories (SNL). Here, we will focus on recent LANL development work, as well as adding additional dimensionality to the barcoding technique. The field of international safeguards employs a broad array of tags, seals, and tamper-indicating devices to assist with identification, tracking, and verification of components and materials. These devices each have unique strengths suited to specific applications, and span a range of technologies from passive metal cup seals and adhesive seals to active, remotely monitored fiber optic seals. Regardless of the technology employed, essential characteristics center around security, environmental and temporal stability, ease of use, and the ability to provide confidence to all parties. Here, we present a new inexpensive tagging technology that will deliver these attributes, while forming the basis of either a new seal, or as a secure layer added to many existing devices. Our approach uses the Surface Enhanced Raman Scattering (SERS) response from SANAs (SERS-Active Nanoparticle Aggregates, Figure 1) to provide a unique identifier or signature for tagging applications. SANAs are formed from gold or silver nanoparticles in the 40-80 nm size range. A chemical dye is installed on the nanoparticle surface, and the nanoparticles are then aggregated into ensembles of {approx}100 to 500 nm diameter, prior to being coated with silica. The silica shell protects the finished SANA from

  1. Air-cathode microbial fuel cell array: a device for identifying and characterizing electrochemically active microbes.

    PubMed

    Hou, Huijie; Li, Lei; de Figueiredo, Paul; Han, Arum

    2011-01-15

    Microbial fuel cells (MFCs) have generated excitement in environmental and bioenergy communities due to their potential for coupling wastewater treatment with energy generation and powering diverse devices. The pursuit of strategies such as improving microbial cultivation practices and optimizing MFC devices has increased power generating capacities of MFCs. However, surprisingly few microbial species with electrochemical activity in MFCs have been identified because current devices do not support parallel analyses or high throughput screening. We have recently demonstrated the feasibility of using advanced microfabrication methods to fabricate an MFC microarray. Here, we extend these studies by demonstrating a microfabricated air-cathode MFC array system. The system contains 24 individual air-cathode MFCs integrated onto a single chip. The device enables the direct and parallel comparison of different microbes loaded onto the array. Environmental samples were used to validate the utility of the air-cathode MFC array system and two previously identified isolates, 7Ca (Shewanella sp.) and 3C (Arthrobacter sp.), were shown to display enhanced electrochemical activities of 2.69 mW/m(2) and 1.86 mW/m(2), respectively. Experiments using a large scale conventional air-cathode MFC validated these findings. The parallel air-cathode MFC array system demonstrated here is expected to promote and accelerate the discovery and characterization of electrochemically active microbes.

  2. New Technologies Promise Dramatic Increase In Capabilities of the Very Large Array

    NASA Astrophysics Data System (ADS)

    1996-06-01

    The National Science Foundation's Very Large Array (VLA) radio telescope in New Mexico is an exceedingly powerful scientific instrument, and has transformed many areas of astronomy in its more than 15 years of operation. It has been used by more astronomers and has produced more scientific papers than any other radio telescope. Though its position as one of the world's premier radio telescopes will remain unchallenged for a long time, new technologies could increase its scientific capabilities greater than tenfold. Details were presented today to the American Astronomical Society's meeting in Madison, Wisconsin. An enhanced VLA, incorporating state-of-the-art technologies, would provide scientists with a number of important, new capabilities, including detailed investigations of the physics of solar radio bursts; improved radar probes of planets, asteroids and comets; the ability to image protoplanetary disks around young stars; more rapid response and effective observations of transient events such as supernovae; new types of information about gas both within our own Galaxy and in other galaxies; and greatly improved ability to study clusters of galaxies and extremely distant objects in the Universe. In addition, the enhanced VLA will serve as an improved partner with the Very Long Baseline Array (VLBA), a continent-wide radio telescope, also part of the National Radio Astronomy Observatory (NRAO). "The VLA upgrade proposes an essentially new instrument, created from two existing instruments, with power and capability far exceeding that of either one alone," said Rick Perley, NRAO Project Scientist for the VLA Upgrade Project. "It builds on the existing staff and infrastructure and would hardly affect operations costs. In today's fiscal climate, this provides the benefit of a `new' instrument with outstanding scientific capability at the least cost," Perley added. The VLA was built in the 1970s and dedicated in 1980. At the time of its completion, it was a state

  3. Fabrication of corner cube array retro-reflective structure with DLP-based 3D printing technology

    NASA Astrophysics Data System (ADS)

    Riahi, Mohammadreza

    2016-06-01

    In this article, the fabrication of a corner cube array retro-reflective structure is presented by using DLP-based 3D printing technology. In this additive manufacturing technology a pattern of a cube corner array is designed in a computer and sliced with specific software. The image of each slice is then projected from the bottom side of a reservoir, containing UV cure resin, utilizing a DLP video projector. The projected area is cured and attached to a base plate. This process is repeated until the entire part is made. The best orientation of the printing process and the effect of layer thicknesses on the surface finish of the cube has been investigated. The thermal reflow surface finishing and replication with soft molding has also been presented in this article.

  4. Sensitivity- and effort-gain analysis: multilead ECG electrode array selection for activation time imaging.

    PubMed

    Hintermüller, Christoph; Seger, Michael; Pfeifer, Bernhard; Fischer, Gerald; Modre, Robert; Tilg, Bernhard

    2006-10-01

    Methods for noninvasive imaging of electric function of the heart might become clinical standard procedure the next years. Thus, the overall procedure has to meet clinical requirements as an easy and fast application. In this paper, we propose a new electrode array which improves the resolution of methods for activation time imaging considering clinical constraints such as easy to apply and compatibility with routine leads. For identifying the body-surface regions where the body surface potential (BSP) is most sensitive to changes in transmembrane potential (TMP), a virtual array method was used to compute local linear dependency (LLD) maps. The virtual array method computes a measure for the LLD in every point on the body surface. The most suitable number and position of the electrodes within the sensitive body surface regions was selected by constructing effort gain (EG) plots. Such a plot depicts the relative attainable rank of the leadfield matrix in relation to the increase in number of electrodes required to build the electrode array. The attainable rank itself was computed by a detector criterion. Such a criterion estimates the maximum number of source space eigenvectors not covered by noise when being mapped to the electrode space by the leadfield matrix and recorded by a detector. From the sensitivity maps, we found that the BSP is most sensitive to changes in TMP on the upper left frontal and dorsal body surface. These sensitive regions are covered best by an electrode array consisting of two L-shaped parts of approximately 30 cm x 30 cm and approximately 20 cm x 20 cm. The EG analysis revealed that the array meeting clinical requirements best and improving the resolution of activation time imaging consists of 125 electrodes with a regular horizontal and vertical spacing of 2-3 cm.

  5. Electrokinetic microactuator arrays for active sublayer control of turbulent boundary layers

    NASA Astrophysics Data System (ADS)

    Diez-Garias, Francisco J.

    2002-09-01

    The present study has been the first to examine the electrokinetic principle as the basis for a new class of microscale actuator arrays for active sublayer control on full scale aeronautical and hydronautical vehicles under realistic operating conditions. The Helmholtz-Smoluchowski scalings that govern such electrokinetic actuator arrays show significant performance advantages from their miniaturization to the microscale. The electrokinetic microactuator arrays that are the subject of this study seek to interrupt the bursting process associated with naturally-occurring streamwise sublayer vortices in the turbulent boundary layer. Specific performance requirements for microactuator spacing, flow rate, and frequency response for active sublayer control have been determined from fundamental scaling laws for the streamwise vortical structures in the sublayer of turbulent boundary layers. In view of the inherently local nature of the sublayer dynamics, a general system architecture for microactuator arrays appropriate for active sublayer control has been developed based on the concept of relatively small and independent "unit cells", each with their own sensing, processing, and actuation capability, that greatly simplifies the sensing and processing requirements needed to achieve practical sublayer control. A fundamental three-layer design has been developed for such electrokinetic microactuator arrays, in which electrokinetic flow is induced by an impulsively applied electric field across a center layer, with a bottom layer containing an electrolyte reservoir and a common electrode, and a top layer that containing individual electrodes and lead-outs for each microactuator in the unit cell. Microfabrication techniques have been developed that permit mass production of large numbers of individual electrokinetic microactuators in unit cells on comparatively large-area tiles. Several generations of such electrokinetic microactuator arrays have been built leading to the

  6. Lightweight active controlled primary mirror technology demonstrator

    NASA Astrophysics Data System (ADS)

    Mazzinghi, P.; Bratina, V.; Ferruzzi, D.; Gambicorti, L.; Simonetti, F.; Zuccaro Marchi, A.; Salinari, P.; Lisi, F.; Olivier, M.; Bursi, A.; Gallieni, D.; Biasi, R.; Pereira, J.

    2007-10-01

    This paper describes the design, manufacturing and test of a ground demonstrator of an innovative technology able to realize lightweight active controlled space-borne telescope mirror. This analysis is particularly devoted to applications for a large aperture space telescope for advanced LIDAR, but it can be used for any lightweight mirror. For a space-borne telescope the mirror weight is a fundamental parameter to be minimized (less than 15 Kg/m2), while maximizing the optical performances (optical quality better than λ/3). In order to guarantee these results, the best selected solution is a thin glass primary mirror coupled to a stiff CFRP (Carbon Fiber Reinforced Plastic) panel with a surface active control system. A preliminary design of this lightweight structure highlighted the critical areas that were deeply analyzed by the ground demonstrator: the 1 mm thick mirror survivability on launch and the actuator functional performances with low power consumption. To preserve the mirror glass the Electrostatic Locking technique was developed and is here described. The active optics technique, already widely used for ground based telescopes, consists of a metrology system (wave front sensor, WFS), a control algorithm and a system of actuators to slightly deform the primary mirror and/or displace the secondary, in a closed-loop control system that applies the computed corrections to the mirror's optical errors via actuators. These actuators types are properly designed and tested in order to guarantee satisfactory performances in terms of stroke, force and power consumption. The realized and tested ground demonstrator is a square CFRP structure with a flat mirror on the upper face and an active actuator beneath it. The test campaign demonstrated the technology feasibility and robustness, supporting the next step toward the large and flat surface with several actuators.

  7. Ultrasound aided photochemical synthesis of Ag loaded TiO2 nanotube arrays to enhance photocatalytic activity.

    PubMed

    Sun, Lan; Li, Jing; Wang, Chenglin; Li, Sifang; Lai, Yuekun; Chen, Hongbo; Lin, Changjian

    2009-11-15

    This work presents a novel approach for preparing TiO(2) nanotube array photocatalyst loaded with highly dispersed Ag nanoparticles through an ultrasound aided photochemical route. The Ag content loaded on the array was controlled by changing the concentration of AgNO(3) solution. The Ag-TiO(2) nanotube arrays were characterized by SEM, XRD, XPS and UV-vis absorption. The effects of Ag content on the photoelectrochemical (PEC) property and photocatalytic activity of TiO(2) nanotube array electrode were studied. The results showed that Ag loading significantly enhanced the photocurrent and photocatalytic degradation rate of TiO(2) nanotube array under UV-light irradiation. The photocurrent and photocatalytic degradation rate of Ag-TiO(2) nanotube array prepared in 0.006 M AgNO(3) solution were about 1.2 and 3.7 times as that of pure TiO(2) nanotube array, respectively.

  8. Radio-selected Binary Active Galactic Nuclei from the Very Large Array Stripe 82 Survey

    NASA Astrophysics Data System (ADS)

    Fu, Hai; Myers, A. D.; Djorgovski, S. G.; Yan, Lin; Wrobel, J. M.; Stockton, A.

    2015-01-01

    Galaxy mergers play an important role in the growth of galaxies and their supermassive black holes. Simulations suggest that tidal interactions could enhance black hole accretion, which can be tested by the fraction of binary active galactic nuclei (AGNs) among galaxy mergers. However, determining the fraction requires a statistical sample of binaries. We have identified kiloparsec-scale binary AGNs directly from high-resolution radio imaging. Inside the 92 deg2 covered by the high-resolution Very Large Array survey of the Sloan Digital Sky Survey (SDSS) Stripe 82 field, we identified 22 grade A and 30 grade B candidates of binary radio AGNs with angular separations less than 5'' (10 kpc at z = 0.1). Eight of the candidates have optical spectra for both components from the SDSS spectroscopic surveys and our Keck program. Two grade B candidates are projected pairs, but the remaining six candidates are all compelling cases of binary AGNs based on either emission line ratios or the excess in radio power compared to the Hα-traced star formation rate. Only two of the six binaries were previously discovered by an optical spectroscopic search. Based on these results, we estimate that ~60% of our binary candidates would be confirmed once we obtain complete spectroscopic information. We conclude that wide-area high-resolution radio surveys offer an efficient method to identify large samples of binary AGNs. These radio-selected binary AGNs complement binaries identified at other wavelengths and are useful for understanding the triggering mechanisms of black hole accretion. Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation.

  9. From Understanding Cellular Function to Novel Drug Discovery: The Role of Planar Patch-Clamp Array Chip Technology

    PubMed Central

    Py, Christophe; Martina, Marzia; Diaz-Quijada, Gerardo A.; Luk, Collin C.; Martinez, Dolores; Denhoff, Mike W.; Charrier, Anne; Comas, Tanya; Monette, Robert; Krantis, Anthony; Syed, Naweed I.; Mealing, Geoffrey A. R.

    2011-01-01

    All excitable cell functions rely upon ion channels that are embedded in their plasma membrane. Perturbations of ion channel structure or function result in pathologies ranging from cardiac dysfunction to neurodegenerative disorders. Consequently, to understand the functions of excitable cells and to remedy their pathophysiology, it is important to understand the ion channel functions under various experimental conditions – including exposure to novel drug targets. Glass pipette patch-clamp is the state of the art technique to monitor the intrinsic and synaptic properties of neurons. However, this technique is labor intensive and has low data throughput. Planar patch-clamp chips, integrated into automated systems, offer high throughputs but are limited to isolated cells from suspensions, thus limiting their use in modeling physiological function. These chips are therefore not most suitable for studies involving neuronal communication. Multielectrode arrays (MEAs), in contrast, have the ability to monitor network activity by measuring local field potentials from multiple extracellular sites, but specific ion channel activity is challenging to extract from these multiplexed signals. Here we describe a novel planar patch-clamp chip technology that enables the simultaneous high-resolution electrophysiological interrogation of individual neurons at multiple sites in synaptically connected neuronal networks, thereby combining the advantages of MEA and patch-clamp techniques. Each neuron can be probed through an aperture that connects to a dedicated subterranean microfluidic channel. Neurons growing in networks are aligned to the apertures by physisorbed or chemisorbed chemical cues. In this review, we describe the design and fabrication process of these chips, approaches to chemical patterning for cell placement, and present physiological data from cultured neuronal cells. PMID:22007170

  10. Bulk CMOS VLSI Technology Studies. Part 1. Scalable CMOS Design Rules. Part 2. CMOS Approaches to PLA (Programmable Logic Array) Design.

    DTIC Science & Technology

    2014-09-26

    microns %H*SIC dimensions. Part 2: Various Programmable Logic Array (PLA) implementations with clocked CMOS technology are explored inthis project...Previous research at MSU has dealt with clocked CMOS circuit styles with some application to gate array and microprocessor applications. Work under this...in this report deals with structured logic schemes based on Programmable Logic Arrays (PLAs). Three different PLA design methods are reported with a

  11. Information and Communications Technology (ICT) Infrastructure for the ASTRI SST-2M telescope prototype for the Cherenkov Telescope Array

    NASA Astrophysics Data System (ADS)

    Gianotti, F.; Tacchini, A.; Leto, G.; Martinetti, E.; Bruno, P.; Bellassai, G.; Conforti, V.; Gallozzi, S.; Mastropietro, M.; Tanci, C.; Malaguti, G.; Trifoglio, M.

    2016-08-01

    The Cherenkov Telescope Array (CTA) represents the next generation of ground-based observatories for very high energy gamma-ray astronomy. The CTA will consist of two arrays at two different sites, one in the northern and one in the southern hemisphere. The current CTA design foresees, in the southern site, the installation of many tens of imaging atmospheric Cherenkov telescopes of three different classes, namely large, medium and small, so defined in relation to their mirror area; the northern hemisphere array would consist of few tens of the two larger telescope types. The Italian National Institute for Astrophysics (INAF) is developing the Cherenkov Small Size Telescope ASTRI SST- 2M end-to-end prototype telescope within the framework of the International Cherenkov Telescope Array (CTA) project. The ASTRI prototype has been installed at the INAF observing station located in Serra La Nave on Mt. Etna, Italy. Furthermore a mini-array, composed of nine of ASTRI telescopes, has been proposed to be installed at the Southern CTA site. Among the several different infrastructures belonging the ASTRI project, the Information and Communication Technology (ICT) equipment is dedicated to operations of computing and data storage, as well as the control of the entire telescope, and it is designed to achieve the maximum efficiency for all performance requirements. Thus a complete and stand-alone computer centre has been designed and implemented. The goal is to obtain optimal ICT equipment, with an adequate level of redundancy, that might be scaled up for the ASTRI mini-array, taking into account the necessary control, monitor and alarm system requirements. In this contribution we present the ICT equipment currently installed at the Serra La Nave observing station where the ASTRI SST-2M prototype will be operated. The computer centre and the control room are described with particular emphasis on the Local Area Network scheme, the computing and data storage system, and the

  12. Electrophoretic and field-effect graphene for all-electrical DNA array technology.

    PubMed

    Xu, Guangyu; Abbott, Jeffrey; Qin, Ling; Yeung, Kitty Y M; Song, Yi; Yoon, Hosang; Kong, Jing; Ham, Donhee

    2014-09-05

    Field-effect transistor biomolecular sensors based on low-dimensional nanomaterials boast sensitivity, label-free operation and chip-scale construction. Chemical vapour deposition graphene is especially well suited for multiplexed electronic DNA array applications, since its large two-dimensional morphology readily lends itself to top-down fabrication of transistor arrays. Nonetheless, graphene field-effect transistor DNA sensors have been studied mainly at single-device level. Here we create, from chemical vapour deposition graphene, field-effect transistor arrays with two features representing steps towards multiplexed DNA arrays. First, a robust array yield--seven out of eight transistors--is achieved with a 100-fM sensitivity, on par with optical DNA microarrays and at least 10 times higher than prior chemical vapour deposition graphene transistor DNA sensors. Second, each graphene acts as an electrophoretic electrode for site-specific probe DNA immobilization, and performs subsequent site-specific detection of target DNA as a field-effect transistor. The use of graphene as both electrode and transistor suggests a path towards all-electrical multiplexed graphene DNA arrays.

  13. A new generation active arrays for optical flexibility in astronomical instrumentation

    NASA Astrophysics Data System (ADS)

    Kroes, G.; Jaskó, A.; Pragt, J. H.; Venema, L.; De Haan, M.

    2012-09-01

    Throughout the history of telescopes and astronomical instrumentation, new ways were found to open up unexplored possibilities in fundamental astronomical research by increasing the telescope size and instrumentation complexity. The ever demanding requirements on instrument performance pushes instrument complexity to the edge. In order to take the next leap forward in instrument development the optical design freedom needs to be increased drastically. The use of more complex and more accurate optics allows for shorter optical trains with smaller sizes, smaller number of components and reduced fabrication and alignment verification time and costs. Current optics fabrication is limited in surface form complexity and/or accuracy. Traditional active and adaptive optics lack the needed intrinsic long term stability and simplicity in design, manufacturing, verification and control. This paper explains how and why active arrays literally provide a flexible but stable basis for the next generation optical instruments. Combing active arrays with optically high quality face sheets more complex and accurate optical surface forms can be provided including extreme a-spherical (freeform) surfaces and thus allow for optical train optimization and even instrument reconfiguration. A zero based design strategy is adopted for the development of the active arrays addressing fundamental issues in opto-mechanical engineering. The various choices are investigated by prototypes and Finite Element Analysis. Finally an engineering concept will be presented following a highly stable adjustment strategy allowing simple verification and control. The Optimization metrology is described in an additional paper for this conference by T. Agócs et al.

  14. EarthScope Transportable Array Siting Outreach Activities in Alaska and Western Canada

    NASA Astrophysics Data System (ADS)

    Gardine, L.; Dorr, P. M.; Tape, C.; McQuillan, P.; Taber, J.; West, M. E.; Busby, R. W.

    2014-12-01

    The EarthScopeTransportable Array is working to locate over 260 stations in Alaska and western Canada. In this region, new tactics and partnerships are needed to increase outreach exposure. IRIS and EarthScope are partnering with the Alaska Earthquake Center, part of University of Alaska Geophysical Institute, to spread awareness of Alaska earthquakes and the benefits of the Transportable Array for Alaskans. Nearly all parts of Alaska are tectonically active. The tectonic and seismic variability of Alaska requires focused attention at the regional level, and the remoteness and inaccessibility of most Alaska villages and towns often makes frequent visits difficult. For this reason, Alaska outreach most often occurs at community events. When a community is accessible, every opportunity to engage the residents is made. Booths at state fairs and large cultural gatherings, such as the annual convention of the Alaska Federation of Natives, are excellent venues to distribute earthquake information and to demonstrate a wide variety of educational products and web-based applications related to seismology and the Transportable Array that residents can use in their own communities. Region-specific publications have been developed to tie in a sense of place for residents of Alaska. The Alaska content for IRIS's Active Earth Monitor will emphasize the widespread tectonic and seismic features and offer not just Alaska residents, but anyone interested in Alaska, a glimpse into what is going on beneath their feet. The concerted efforts of the outreach team will have lasting effects on Alaskan understanding of the seismic hazard and tectonics of the region. Efforts to publicize the presence of the Transportable Array in Alaska, western Canada, and the Lower 48 also continue. There have been recent articles published in university, local and regional newspapers; stories appearing in national and international print and broadcast media; and documentaries produced by some of the world

  15. A 64 single photon avalanche diode array in 0.18 µm CMOS standard technology with versatile quenching circuit for quick prototyping

    NASA Astrophysics Data System (ADS)

    Uhring, Wilfried; Le Normand, Jean-Pierre; Zint, Virginie; Dumas, Norbert; Dadouche, Foudil; Malasse, Imane; Scholz, Jeremy

    2012-04-01

    Several works have demonstrated the successfully integration of Single-photon avalanche photodiodes (SPADs) operating in Geiger mode in a standard CMOS circuit for the last 10 years. These devices offer an exceptional temporal resolution as well as a very good optical sensitivity. Nevertheless, it is difficult to predict the expected performances of such a device. Indeed, for a similar structure of SPAD, some parameter values can differ by two orders of magnitude from a technology to another. We proposed here a procedure to identify in just one or two runs the optimal structure of SPAD available for a given technology. A circuit with an array of 64 SPAD has been realized in the Tower-Jazz 0.18 μm CMOS image sensor process. It encompasses an array of 8 different structures of SPAD reproduced in 8 diameters in the range from 5 μm up to 40 μm. According to the SPAD structures, efficient shallow trench insulator and/or P-Well guard ring are used for preventing edge breakdown. Low dark count rate of about 100 Hz are expected thanks to the use of buried n-well layer and a high resistivity substrate. Each photodiode is embedded in a pixel which includes a versatile quenching circuitry and an analog output of its cathode voltage. The quenching system is configurable in four operation modes; the SPAD is disabled, the quenching is completely passive, the reset of the photodiode is active and the quenching is fully active. The architecture of the array makes possible the characterization of every single photodiode individually. The parameters to be measured for a SPAD are the breakdown avalanche voltage, the dark count rate, the dead time, the timing jitter, the photon detection probability and the after-pulsing rate.

  16. An active K/Ka-band antenna array for the NASA ACTS mobile terminal

    NASA Technical Reports Server (NTRS)

    Tulintseff, A.; Crist, R.; Densmore, Art; Sukamto, L.

    1993-01-01

    An active K/Ka-band antenna array is currently under development for NASA's ACTS Mobile Terminal (AMT). The AMT task will demonstrate voice, data, and video communications to and from the AMT vehicle in Los Angeles, California, and a base station in Cleveland, Ohio, via the ACTS satellite at 30 and 20 GHz. Satellite tracking for the land-mobile vehicular antenna system involves 'mechanical dithering' of the antenna, where the antenna radiates a fixed beam 46 deg. above the horizon. The antenna is to transmit horizontal polarization and receive vertical polarization at 29.634 plus or minus 0.15 GHz and 19.914 plus or minus 0.15 GHz, respectively. The active array will provide a minimum of 22 dBW EIRP transmit power density and a -8 dB/K deg. receive sensitivity.

  17. An active K/Ka-band antenna array for the NASA ACTS mobile terminal

    NASA Astrophysics Data System (ADS)

    Tulintseff, A.; Crist, R.; Densmore, Art; Sukamto, L.

    An active K/Ka-band antenna array is currently under development for NASA's ACTS Mobile Terminal (AMT). The AMT task will demonstrate voice, data, and video communications to and from the AMT vehicle in Los Angeles, California, and a base station in Cleveland, Ohio, via the ACTS satellite at 30 and 20 GHz. Satellite tracking for the land-mobile vehicular antenna system involves 'mechanical dithering' of the antenna, where the antenna radiates a fixed beam 46 deg. above the horizon. The antenna is to transmit horizontal polarization and receive vertical polarization at 29.634 plus or minus 0.15 GHz and 19.914 plus or minus 0.15 GHz, respectively. The active array will provide a minimum of 22 dBW EIRP transmit power density and a -8 dB/K deg. receive sensitivity.

  18. Research of improved sparse grid non-uniformity correction technologies for infrared resistor array

    NASA Astrophysics Data System (ADS)

    Du, Hui-jie; Zhao, Hong-ming; Gao, Yang; Yu, Hong; Zhang, Yi

    2015-10-01

    Infrared resistor arrays perform a vital role in the hardware in the loop testing of infrared seekers. Infrared resistor arrays composed of large numbers of suspended resistor elements are commonly used to produce dynamic two-dimensional images of infrared radiation. Due to inconsistencies in the fabrication process of the resistor arrays, the temperature each resistor elements reaches for a given input voltage is variable and this leads to more significant radiance differences, these differences result in spatially-distributed radiance non-uniformity. Therefore, in order to obtain an available infrared image, non-uniformity correction (NUC) is necessary. In this paper, the non-uniformity characters of the infrared resistor arrays are analyzed base on measured data and then an improved sparse grid method for engineering are discussed and analyzed. First of all, the NUC camera has a strong influence on the effectiveness of the infrared resistor arrays NUC procedure. According to the actual fact and the laboratory condition, we presented an alternative method for collecting resistor arrays intended to reduce the influence causing by the NUC camera. Secondly, based on the measured non-uniformity data, we obtain the response characteristics of the infrared resistor arrays. In each gray level, we take two points or several points correction algorithm to calculate the gain data and the offset data, and then the linear look-up table is established. Finally, through MATLAB we develop the correction software, and we can obtain the driving output conveniently. The result shows that the image quality has a remarkable improvement after non-uniformity correction, the non-uniformity correction flow and algorithm preferably satisfies the requirement of the high confidence infrared imaging simulation.

  19. Magnetic Field Measurements in Wire-Array Z-Pinches using Magneto-Optically Active Waveguides

    NASA Astrophysics Data System (ADS)

    Syed, Wasif; Hammer, David; Lipson, Michal

    2007-11-01

    Understanding the magnetic field topology in wire-array Z-pinches as a function of time is of great significance to understanding these high-energy density plasmas. We are developing techniques to measure magnetic fields as a function of space and time using Faraday rotation of a single longitudinal mode (SLM) laser through a magneto-optically active bulk waveguide (terbium borate glass) placed adjacent to, or within, the wire array in experiments on the COBRA pulsed power generator [1]. We have measured fields >10 T with 100 ns rise times outside of a wire-array for the entire duration of the current pulse and as much as ˜2 T inside a wire-array for ˜40 ns from the start of current. This is the first time that such rapidly varying and large fields have been measured using these materials. We will also present our progress on field measurements using an optical fiber sensor and a very small ``thin film waveguide'' coupled to a fiber optic system. In a dense Z-pinch, these sensing devices may not survive for long but may provide the magnetic field at the position of the sensor for a greater fraction of the current pulse than magnetic probes, with which we compare our results. This research was sponsored by NNSA under SSAA program via DOE Coop Agreement DE-F03-02NA00057. [1] W. Syed, D. A. Hammer, & M. Lipson, 34^th ICOPS & 16^th PPPS, Albuquerque, NM, June 2007.

  20. Magnetic Field Measurements in Wire-Array Z-Pinches using Magneto-Optically Active Waveguides

    SciTech Connect

    Syed, Wasif; Blesener, Isaac; Hammer, David A.; Lipson, Michal

    2009-01-21

    Understanding the magnetic field topology in wire-array Z-pinches as a function of time is of great significance to understanding these high-energy density plasmas especially for their ultimate application to stockpile stewardship and inertial confinement fusion. We are developing techniques to measure magnetic fields as a function of space and time using Faraday rotation of a single longitudinal mode (SLM) laser through a magneto-optically active bulk waveguide (multicomponent terbium borate glass) placed adjacent to, or within, the wire array in 1 MA experiments. We have measured fields >10 T with 100 ns rise times outside of a wire-array for the entire duration of the current pulse and as much as {approx}2 T inside a wire-array for {approx}40 ns from the start of current. This is the first time that such rapidly varying and large fields have been measured using these materials. In a dense Z-pinch, these sensing devices may not survive for long but may provide the magnetic field at the position of the sensor that can be used to corroborate magnetic probes, with which we compare our results.

  1. NASA's Microgravity Technology Report, 1996: Summary of Activities

    NASA Technical Reports Server (NTRS)

    Kierk, Isabella

    1996-01-01

    This report covers technology development and technology transfer activities within the Microgravity Science Research Programs during FY 1996. It also describes the recent major tasks under the Advanced Technology Development (ATD) Program and identifies current technology requirements. This document is consistent with NASA,s Enteprise for the Human Exploration and development of Space (HEDS) Strategic Plan. This annual update reflects changes in the Microgravity Science Research Program's new technology activities and requirements. Appendix A. FY 1996 Advanced Technology Development. Program and Project Descriptions. Appendix B. Technology Development.

  2. In-Space and Terrestrial Solar Array Technologies for Beamed Laser Power Systems

    NASA Astrophysics Data System (ADS)

    Brandhorst, Henry W.; O'Neill, Mark J.

    2002-01-01

    The Stretched Lens Array (SLA) has been proposed as an integral part of the POWOW concept for an electrically propelled spacecraft traveling to Mars and using lasers to beam power to the surface. Significant advances in the design of the (SLA) have recently been accomplished. These advances include thinner lenses, more efficient cells, stiffer, lighter array structures, higher operating voltages, plus demonstration of a subscale model of the array concept. These advances will be described. The SLA has continued to evolve into a cost-effective, high specific power and high power density array and this array is applicable to a wide range of commercial, civil and other applications. This broad applicability stems in part because POWOW was a modular design using solar array building blocks in the 8 kW size. The integration of solar energy conversion in space with laser power transmission of that energy allows the use of photovoltaic receivers on the surface as well. Concentrator arrays built on the same concept as the SLA have been demonstrated on earth for some time. It is important to note that DoE tests over several years have shown the superior performance of this type of array. The results of these terrestrial tests will be described as well. Because the most likely location for a power beaming satellite is in a synchronous orbit (GEO for Earth), concentrator arrays appear well suited as the receivers for laser beams from those satellites. The ability to control operating temperature with appropriate design and to reduce the amount of more expensive solar cell material seems to be a cost-effective solution. Thus the adaptation of the linear Fresnel concentrators for this application is worthy of examination. The third issue that is critical for successful power conversion is selection of the laser wavelength/solar cell combination to maximize efficiency. Selection of the cell type involves several issues: laser wavelength, band gap (direct or indirect), operating

  3. Non-destructive evaluation of adhesive layer using a planar array capacitive imaging technology

    NASA Astrophysics Data System (ADS)

    Zhang, Yuyan; Zhao, Limei; Wen, Yintang; Sun, Dongtao

    2016-04-01

    The thermal protection materials for aircraft are usually assembled on the substrate surface by means of adhesion agent. It is very necessary to evaluate the interface bonding quality which has great influence on heat preservation performance. At present, there is still no relatively satisfactory and reliable method for defect detection of cohesive coating. Planar array electrical capacitance tomography (ECT) is a suitable non-invasive imaging technique when there is only limited access to the targeted object. This research aims to investigate the feasibility of using planar array electrical capacitive tomography for bondline defect detection. In this paper, a planar array ECT system is developed consist of a planar array sensor of 12 electrodes, a capacitance acquisition system and image reconstruction software. The sensor development, simulation of sensitivity map, practical application and imaging reconstruction are discussed. A series of specimens of thermal protection material with man-made defects are tested by the proposed planar array ECT system. The experimental results show that the defect in cohesive coating can be effectively detected and the minimum size can be detected is 10mm×10mm.

  4. A 2x2 W-Band Reference Time-Shifted Phase-Locked Transmitter Array in 65nm CMOS Technology

    NASA Technical Reports Server (NTRS)

    Tang, Adrian; Virbila, Gabriel; Hsiao, Frank; Wu, Hao; Murphy, David; Mehdi, Imran; Siegel, P. H.; Chang, M-C. Frank

    2013-01-01

    This paper presents a complete 2x2 phased array transmitter system operating at W-band (90-95 GHz) which employs a PLL reference time-shifting approach instead of using traditional mm-wave phase shifters. PLL reference shifting enables a phased array to be distributed over multiple chips without the need for coherent mm-wave signal distribution between chips. The proposed phased array transmitter system consumes 248 mW per array element when implemented in a 65 nm CMOS technology.

  5. FSA future directions: FSA technology activities in FY86

    NASA Technical Reports Server (NTRS)

    Leipold, M. H.

    1985-01-01

    The silicon material, advanced silicon sheet, device research, and process research activities are explained. There will be no new initiatives. Many activities are targeted for completion and the emphasis will then be on technology transfer. Industrial development of the fluidized-bed reactor (FBR) deposition technology is proceeding. Technology transfer and industry funding of sheet development are continuing.

  6. Enhancing absorption in coated semiconductor nanowire/nanorod core-shell arrays using active host matrices

    NASA Astrophysics Data System (ADS)

    Jule, Leta; Dejene, Francis; Roro, Kittessa

    2016-12-01

    In the present work, we investigated theoretically and experimentally the interaction of radiation field phenomena interacting with arrays of nanowire/nanorod core-shell embedded in active host matrices. The optical properties of composites are explored including the case when the absorption of propagating wave by dissipative component is completely compensated by amplification in active (lasing) medium. On the basis of more elaborated modeling approach and extended effective medium theory, the effective polarizability and the refractive index of electromagnetic mode dispersion of the core-shell nanowire arrays are derived. ZnS(shell)-coated by sulphidation process on ZnO(shell) nanorod arrays grown on (100) silicon substrate by chemical bath deposition (CBD) has been used for theoretical comparison. Compared with the bare ZnO nanorods, ZnS-coated core/shell nanorods exhibit a strongly reduced ultraviolet (UV) emission and a dramatically enhanced deep level (DL) emission. Obviously, the UV and DL emission peaks are attributed to the emissions of ZnO nanorods within ZnO/ZnS core/shell nanorods. The reduction of UV emission after ZnS coating seems to agree with the charge separation mechanism of type-II band alignment that holes transfer from the core to shell, which would quench the UV emission to a certain extent. Our theoretical calculations and numerical simulation demonstrate that the use of active host (amplifying) medium to compensate absorption at metallic inclusions. Moreover the core-shell nanorod/nanowire arrays create the opportunity for broad band absorption and light harvesting applications.

  7. EarthScope Transportable Array Siting Outreach Activities in Alaska and Western Canada

    NASA Astrophysics Data System (ADS)

    Dorr, P. M.; Gardine, L.; Tape, C.; McQuillan, P.; Cubley, J. F.; Samolczyk, M. A.; Taber, J.; West, M. E.; Busby, R.

    2015-12-01

    The EarthScope Transportable Array is deploying about 260 stations in Alaska and western Canada. IRIS and EarthScope are partnering with the Alaska Earthquake Center, part of the University of Alaska's Geophysical Institute, and Yukon College to spread awareness of earthquakes in Alaska and western Canada and the benefits of the Transportable Array for people living in these regions. We provide an update of ongoing education and outreach activities in Alaska and Canada as well as continued efforts to publicize the Transportable Array in the Lower 48. Nearly all parts of Alaska and portions of western Canada are tectonically active. The tectonic and seismic variability of Alaska, in particular, requires focused attention at the regional level, and the remoteness and inaccessibility of most Alaskan and western Canadian villages and towns often makes frequent visits difficult. When a community is accessible, every opportunity to engage the residents is made. Booths at state fairs and large cultural gatherings, such as the annual convention of the Alaska Federation of Natives, are excellent venues to distribute earthquake information and to demonstrate a wide variety of educational products and web-based applications related to seismology and the Transportable Array that residents can use in their own communities. Meetings and interviews with Alaska Native Elders and tribal councils discussing past earthquakes has led to a better understanding of how Alaskans view and understand earthquakes. Region-specific publications have been developed to tie in a sense of place for residents of Alaska and the Yukon. The Alaska content for IRIS's Active Earth Monitor emphasizes the widespread tectonic and seismic features and offers not just Alaska residents, but anyone interested in Alaska, a glimpse into what is going on beneath their feet. The concerted efforts of the outreach team will have lasting effects on Alaskan and Canadian understanding of the seismic hazard and

  8. Economic impact of stimulated technological activity: Bibliography

    NASA Technical Reports Server (NTRS)

    1971-01-01

    This bibliography is divided into three parts and covers: (1) overall economic impact of technological progress and its measurement; (2) technological progress and commercialization of communications satellites; and (3) knowledge additions and earth links from space crew systems.

  9. Optically controlled phased-array antenna technology for space communication systems

    NASA Technical Reports Server (NTRS)

    Kunath, Richard R.; Bhasin, Kul B.

    1988-01-01

    Using MMICs in phased-array applications above 20 GHz requires complex RF and control signal distribution systems. Conventional waveguide, coaxial cable, and microstrip methods are undesirable due to their high weight, high loss, limited mechanical flexibility and large volume. An attractive alternative to these transmission media, for RF and control signal distribution in MMIC phased-array antennas, is optical fiber. Presented are potential system architectures and their associated characteristics. The status of high frequency opto-electronic components needed to realize the potential system architectures is also discussed. It is concluded that an optical fiber network will reduce weight and complexity, and increase reliability and performance, but may require higher power.

  10. Terpene sensor array with bridge-type resistors by CMOS technology

    NASA Astrophysics Data System (ADS)

    Lee, Sung Pil

    2015-07-01

    The interaction of terpene gas with the sensing element in the sensor array can cause changes in electrical properties because of a charge transfer and the polymer chain structure. Resistive type interdigited electrode sensor arrays covered with a mixture of molecularly imprinted polymer (MIP)/conductive polymer (CP) were designed and fabricated to detect terpene gases. MIP coated on CP (MOC) type showed markedly higher sensitivity compared to mixture of MIP and CP (MMC) type. The gas detection patterns by PCA were used to get higher selectivity of multicomponent chemical media.

  11. Toward Active-Matrix Lab-On-A-Chip: Programmable Electrofluidic control Enaled by Arrayed Oxide Thin Film Transistors

    SciTech Connect

    Noh, Joo Hyon; Noh, Jiyong; Kreit, Eric; Heikenfeld, Jason; Rack, Philip D

    2012-01-01

    Agile micro- and nano-fluidic control is critical to numerous life science and chemical science synthesis as well as kinetic and thermodynamic studies. To this end, we have demonstrated the use of thin film transistor arrays as an active matrix addressing method to control an electrofluidic array. Because the active matrix method minimizes the number of control lines necessary (m + n lines for the m x n element array), the active matrix addressing method integrated with an electrofluidic platform can be a significant breakthrough for complex electrofluidic arrays (increased size or resolution) with enhanced function, agility and programmability. An amorphous indium gallium zinc oxide (a-IGZO) semiconductor active layer is used because of its high mobility of 1-15 cm{sup 2} V{sup -1} s{sup -1}, low-temperature processing and transparency for potential spectroscopy and imaging. Several electrofluidic functionalities are demonstrated using a simple 2 x 5 electrode array connected to a 2 x 5 IGZO thin film transistor array with the semiconductor channel width of 50 {mu}m and mobility of 6.3 cm{sup 2} V{sup -1} s{sup -1}. Additionally, using the TFT device characteristics, active matrix addressing schemes are discussed as the geometry of the electrode array can be tailored to act as a storage capacitor element. Finally, requisite material and device parameters are discussed in context with a VGA scale active matrix addressed electrofluidic platform.

  12. Toward active-matrix lab-on-a-chip: programmable electrofluidic control enabled by arrayed oxide thin film transistors.

    PubMed

    Noh, Joo Hyon; Noh, Jiyong; Kreit, Eric; Heikenfeld, Jason; Rack, Philip D

    2012-01-21

    Agile micro- and nano-fluidic control is critical to numerous life science and chemical science synthesis as well as kinetic and thermodynamic studies. To this end, we have demonstrated the use of thin film transistor arrays as an active matrix addressing method to control an electrofluidic array. Because the active matrix method minimizes the number of control lines necessary (m + n lines for the m×n element array), the active matrix addressing method integrated with an electrofluidic platform can be a significant breakthrough for complex electrofluidic arrays (increased size or resolution) with enhanced function, agility and programmability. An amorphous indium gallium zinc oxide (a-IGZO) semiconductor active layer is used because of its high mobility of 1-15 cm(2) V(-1) s(-1), low-temperature processing and transparency for potential spectroscopy and imaging. Several electrofluidic functionalities are demonstrated using a simple 2 × 5 electrode array connected to a 2 × 5 IGZO thin film transistor array with the semiconductor channel width of 50 μm and mobility of 6.3 cm(2) V(-1) s(-1). Additionally, using the TFT device characteristics, active matrix addressing schemes are discussed as the geometry of the electrode array can be tailored to act as a storage capacitor element. Finally, requisite material and device parameters are discussed in context with a VGA scale active matrix addressed electrofluidic platform.

  13. Low-volume multiplexed proteolytic activity assay and inhibitor analysis through a pico-injector array.

    PubMed

    Ng, Ee Xien; Miller, Miles A; Jing, Tengyang; Lauffenburger, Doug A; Chen, Chia-Hung

    2015-02-21

    Secreted active proteases, from families of enzymes such as matrix metalloproteinases (MMPs) and ADAMs (a disintegrin and metalloproteinases), participate in diverse pathological processes. To simultaneously measure multiple specific protease activities, a series of parallel enzyme reactions combined with a series of inhibitor analyses for proteolytic activity matrix analysis (PrAMA) are essential but limited due to the sample quantity requirements and the complexity of performing multiple reactions. To address these issues, we developed a pico-injector array to generate 72 different reactions in picoliter-volume droplets by controlling the sequence of combinational injections, which allowed simultaneous recording of a wide range of multiple enzyme reactions and measurement of inhibitor effects using small sample volumes (~10 μL). Multiple MMP activities were simultaneously determined by 9 different substrates and 2 inhibitors using injections from a pico-injector array. Due to the advantages of inhibitor analysis, the MMP/ADAM activities of MDA-MB-231, a breast cancer cell line, were characterized with high MMP-2, MMP-3 and ADAM-10 activity. This platform could be customized for a wide range of applications that also require multiple reactions with inhibitor analysis to enhance the sensitivity by encapsulating different chemical sensors.

  14. Optimal activation of carboxyl-superparamagnetic iron oxide nanoparticles bioconjugated with antibody using orthogonal array design.

    PubMed

    Liu, Lin; Zhang, Xiaoqang; Zhang, Yu; Pu, Yuepu; Yin, Lihong; Tang, Meng; Liu, Hui

    2013-12-01

    This study aims to bioconjugate anti-EMMPRIN monoclonal antibody on the surface of carboxyl-SPIO nanoparticles and to optimize the activated conditions of bioconjugation. Anti-EMMPRIN monoclonal antibody bioconjugated carboxyl-SPIO nanoparticles were performed through a coupling strategy of EDC and sulfo-NHS. The procedure was comprised of two steps by activation of carboxyl-SPIO nanoparticles and conjugation with monoclonal antibody. The optimal activated parameters of bioconjugation were evaluated by single factor design and orthogonal array design. SDS-PAGE analysis and Bradford assay was used for testing and verifying the efficiency of activated conditions obtained from orthogonal array. The results show that pH value, temperature and reaction time were important factors that influence bioconjugated efficiency. The activated parameters with pH value 6.2, temperature 25 degrees C and reaction time 30 min were obviously optimal for activation of carboxyl-SPIO nanoparticles and conjugation with monoclonal EMMPEIN antibody. This coupling strategy for anti-EMMPRIN mAb bioconjugated on SPIO nanoparticles was efficient, and may be further applied in the fields of medical or biological practices.

  15. Teaching the History of Technology. A Cooperative Learning Activity.

    ERIC Educational Resources Information Center

    MacKinnon, Gregory R.

    1999-01-01

    Discusses the importance of the historical context of technology and offers a cooperative-learning activity that highlights Elijah McCoy, a black inventor who was a notable contributor to technological development in the 1800s. (JOW)

  16. Active plasmonic switching at mid-infrared wavelengths with graphene ribbon arrays

    NASA Astrophysics Data System (ADS)

    Chu, Hong-Son; How Gan, Choon

    2013-06-01

    An active plasmonic switch based on single- and few-layer doped graphene ribbon array operating in the mid-infrared spectrum is investigated with theoretical and numerical calculations. It is shown that significant resonance wavelength shifts and modulation depths can be achieved with a slight variation of the doping concentration of the graphene ribbon. The few-layer graphene ribbon array device outperforms the single-layer one in terms of the achievable modulation depth. Our simulations reveal that, by modulating the Fermi-energy level between 0.2 eV and 0.25 eV, a four-layer graphene ribbon array device can achieve a modulation depth and resonance wavelength shift of ˜13 dB and 0.94 μm, respectively, compared to ˜2.8 dB and 1.85 μm for a single-layer device. Additionally, simple fitting models to predict the modulation depth and the resonance wavelength shift are proposed. These prospects pave the way towards ultrafast active graphene-based plasmonic devices for infrared and THz applications.

  17. Production of Uniform 3D Microtumors in Hydrogel Microwell Arrays for Measurement of Viability, Morphology, and Signaling Pathway Activation

    PubMed Central

    Singh, Manjulata; Close, David A.; Mukundan, Shilpaa; Johnston, Paul A.

    2015-01-01

    Abstract Despite significant investments in cancer research and drug discovery/development, the rate of new cancer drug approval is ≤5% and most cases of metastatic cancer remain incurable. Ninety-five percent of new cancer drugs fail in clinical development because of a lack of therapeutic efficacy and/or unacceptable toxicity. One of the major factors responsible for the low success rate of anticancer drug development is the failure of preclinical models to adequately recapitulate the complexity and heterogeneity of human cancer. For throughput and capacity reasons, high-throughput screening growth inhibition assays almost exclusively use two-dimensional (2D) monolayers of tumor cell lines cultured on tissue culture-treated plastic/glass surfaces in serum-containing medium. However, these 2D tumor cell line cultures fail to recapitulate the three-dimensional (3D) context of cells in solid tumors even though the tumor microenvironment has been shown to have a profound effect on anticancer drug responses. Tumor spheroids remain the best characterized and most widely used 3D models; however, spheroid sizes tend to be nonuniform, making them unsuitable for high-throughput drug testing. To circumvent this challenge, we have developed defined size microwell arrays using nonadhesive hydrogels that are applicable to a wide variety of cancer cell lines to fabricate size-controlled 3D microtumors. We demonstrate that the hydrogel microwell array platform can be applied successfully to generate hundreds of uniform microtumors within 3–6 days from many cervical and breast, as well as head and neck squamous cell carcinoma (HNSCC) cells. Moreover, controlling size of the microwells in the hydrogel array allows precise control over the size of the microtumors. Finally, we demonstrate the application of this platform technology to probe activation as well as inhibition of epidermal growth factor receptor (EGFR) signaling in 3D HNSCC microtumors in response to EGF and

  18. Frequency translating phase conjugation circuit for active retrodirective antenna array. [microwave transmission

    NASA Technical Reports Server (NTRS)

    Chernoff, R. (Inventor)

    1980-01-01

    An active retrodirective antenna array which has central phasing from a reference antenna element through a "tree" structured network of transmission lines utilizes a number of phase conjugate circuits (PCCs) at each node and a phase reference regeneration circuit (PRR) at each node except the initial node. Each node virtually coincides with an element of the array. A PCC generates the exact conjugate phase of an incident signal using a phase locked loop which combines the phases in an up converter, divides the sum by 2 and mixes the result with the phase in a down converter for phase detection. The PRR extracts the phase from the conjugate phase. Both the PCC and the PRR are not only exact but also free from mixer degeneracy.

  19. STUDIES OF NORMAL GENE EXPRESSION IN THE RAT NASAL EPITHELIUM USNG CDNA ARRAY TECHNOLOGY

    EPA Science Inventory


    Studies of Normal Gene Expression in the Rat Nasal Epithelium Using cDNA Array

    The nasal epithelium is an important target site for chemically-induced toxicity and carcinogenicity .Gene expression data are being used increasingly for studies of such conditions. In or...

  20. Investigation of spherical loudspeaker arrays for local active control of sound.

    PubMed

    Peleg, Tomer; Rafaely, Boaz

    2011-10-01

    Active control of sound can be employed globally to reduce noise levels in an entire enclosure, or locally around a listener's head. Recently, spherical loudspeaker arrays have been studied as multiple-channel sources for local active control of sound, presenting the fundamental theory and several active control configurations. In this paper, important aspects of using a spherical loudspeaker array for local active control of sound are further investigated. First, the feasibility of creating sphere-shaped quiet zones away from the source is studied both theoretically and numerically, showing that these quiet zones are associated with sound amplification and poor system robustness. To mitigate the latter, the design of shell-shaped quiet zones around the source is investigated. A combination of two spherical sources is then studied with the aim of enlarging the quiet zone. The two sources are employed to generate quiet zones that surround a rigid sphere, investigating the application of active control around a listener's head. A significant improvement in performance is demonstrated in this case over a conventional headrest-type system that uses two monopole secondary sources. Finally, several simulations are presented to support the theoretical work and to demonstrate the performance and limitations of the system.

  1. Arrayed Waveguide Gratings and Their Application Using Super-High-Δ Silica-Based Planar Lightwave Circuit Technology

    NASA Astrophysics Data System (ADS)

    Maru, Koichi; Uetsuka, Hisato

    This paper reviews our recent progress on arrayed waveguide gratings (AWGs) using super-high-Δ silica-based planar lightwave circuit (PLC) technology and their application to integrated optical devices. Factors affecting the chip size of AWGs and the impact of increasing relative index difference Δ on the chip size are investigated, and the fabrication result of a compact athermal AWG using 2.5%-Δ silica-based waveguides is presented. As an application of super-high-Δ AWGs to integrated devices, a flat-passband multi/demultiplexer consisting of an AWG and cascaded MZIs is presented.

  2. A MULTIPLEXED ASSAY FOR DETERMINATION OF NEUROTOXICANT EFFECTS ON SPONTANEOUS NETWORK ACTIVITY AND CELL VIABILITY FROM MICROELECTRODE ARRAYS

    EPA Science Inventory

    AbstractTITLE: A MULTIPLEXED ASSAY FOR DETERMINATION OF NEUROTOXICANT EFFECTS ON SPONTANEOUS NETWORK ACTIVITY AND CELL VIABILITY FROM MICROELECTRODE ARRAYSABSTRACT BODY: Microelectrode array (MEA) recordings are increasingly being used as an in vitro method to detect and characte...

  3. Neural Activity Propagation in an Unfolded Hippocampal Preparation with a Penetrating Micro-electrode Array

    PubMed Central

    Gonzales-Reyes, Luis E.; Durand, Dominique M.

    2015-01-01

    This protocol describes a method for preparing a new in vitro flat hippocampus preparation combined with a micro-machined array to map neural activity in the hippocampus. The transverse hippocampal slice preparation is the most common tissue preparation to study hippocampus electrophysiology. A longitudinal hippocampal slice was also developed in order to investigate longitudinal connections in the hippocampus. The intact mouse hippocampus can also be maintained in vitro because its thickness allows adequate oxygen diffusion. However, these three preparations do not provide direct access to neural propagation since some of the tissue is either missing or folded. The unfolded intact hippocampus provides both transverse and longitudinal connections in a flat configuration for direct access to the tissue to analyze the full extent of signal propagation in the hippocampus in vitro. In order to effectively monitor the neural activity from the cell layer, a custom made penetrating micro-electrode array (PMEA) was fabricated and applied to the unfolded hippocampus. The PMEA with 64 electrodes of 200 µm in height could record neural activity deep inside the mouse hippocampus. The unique combination of an unfolded hippocampal preparation and the PMEA provides a new in-vitro tool to study the speed and direction of propagation of neural activity in the two-dimensional CA1-CA3 regions of the hippocampus with a high signal to noise ratio. PMID:25868081

  4. Active millimeter-wave video rate imaging with a staring 120-element microbolometer array

    NASA Astrophysics Data System (ADS)

    Luukanen, Arttu; Miller, Aaron J.; Grossman, Erich N.

    2004-08-01

    Passive indoors imaging of weapons concealed under clothing poses a formidable challenge for millimeter-wave imagers due to the sub-picowatt signal levels present in the scene. Moreover, video-rate imaging requires a large number of pixels, which leads to a very complex and expensive front end for the imager. To meet the concealed weapons detection challenge, our approach uses a low cost pulsed-noise source as an illuminator and an array of room-temperature antenna-coupled microbolometers as the detectors. The reflected millimeter-wave power is detected by the bolometers, gated, integrated and amplified by audio-frequency amplifiers, and after digitization, displayed in real time on a PC display. We present recently acquired videos obtained with the 120-element array, and comprehensively describe the performance characteristics of the array in terms of sensitivity, optical efficiency, uniformity and spatial resolution. Our results show that active imaging with antenna-coupled microbolometers can yield imagery comparable to that obtained with systems using MMIC amplifiers but with a cost per pixel that is orders of magnitude lower.

  5. A new method for anisotropic materials characterization based on phased-array ultrasonic transducers technology

    SciTech Connect

    Frenet, D.; Calmon, P.; Paradis, L.

    1999-12-02

    A method for materials characterization based on the utilization of a ultrasonic array transducer of conical shape has been developed at the CEA. The specific design of this transducer allows the generation and the detection of leaky surface acoustic waves (LSAW) in an efficient way. Additionally, anisotropic materials can be investigated in several azimuthal directions without any mechanical movement. The characterization process relies on the velocity measurement of the LSAW. Experimental results on both isotropic an anisotropic material are reported.

  6. Design and Simulation of a Programmable Memory/Multiplier Array Using G4-FET Technology

    DTIC Science & Technology

    2007-07-01

    bias to each of the four gates changes the shape of the channel, controlling the conduction path. Figure 4 illustrates the effects of the MOSFET top...further narrowing the channel. MOSFET gate JFET gates Figure 4: G4-FET top MOS gate and side JFET gates control channel current By using these...ABSTRACT Field-programmable and mask-programmable gate arrays can greatly reduce the non-recurring costs of ASIC development by reusing both masks and

  7. Technology for fabricating micro-lens arrays utilizing lithographically replicated concave resist patterns

    NASA Astrophysics Data System (ADS)

    Kobayashi, Noa; Sasaki, Ryunosuke; Horiuchi, Toshiyuki

    2016-05-01

    Lithography has been generally used for printing two-dimensional patterns on flat wafers. Recently, however, it is also applied to a three-dimensional patterning for fabricating various MEMS (Micro Electro Mechanical Systems) components. The purpose of this research is to develop a new method for fabricating micro-lens arrays. At first, resist (Tokyo Ohka Kogyo, PMER LA-900PM) mold patterns with densely arrayed square or hexagonal concaves were replicated by intentionally shifting the focal position of projection exposure. The size of resist-mold was 2 mm square, and the initial thickness of the resist was 10 μm. Next, the wafer with the concave resist patterns was cut into small chips, and each wafer chip was fixed at the bottom of a paper cup using an adhesive tape. Then the epoxy resin (Nissin resin, Crystal resin Neo) was poured on the concave resist-mold patterns, and the resin was coagulated. Afterward, the hardened resin was grooved along the wafer chip using a cutter knife, and the wafer chip with the resist-mold patterns was forcibly removed using a pair of tweezers. Finally, both sides of the resin block were polished, and the thickness was reduced. Although the transparency and roughness of the resin block surfaces should be improved, epoxy micro-lens arrays were certainly fabricated. The mean values of curvature radius and lens height were 28.3μm and 4.9 μm, respectively.

  8. Economic impact of stimulated technological activity

    NASA Technical Reports Server (NTRS)

    1971-01-01

    The findings are reported of research into the relationships between technological progress and economic development, with emphasis on several ways in which NASA research and development has aided in the accumulation and commercial application of new or improved scientific and technological knowledge.

  9. A novel high throughput method based on the DPPH dry reagent array for determination of antioxidant activity.

    PubMed

    Musa, Khalid Hamid; Abdullah, Aminah; Kuswandi, Bambang; Hidayat, M Amrun

    2013-12-15

    A stable chromogenic radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) is commonly used for the determination of antioxidant activity. In this paper, DPPH was dried into 96 well microplate to produce DPPH dry reagent array plate, based on which the highly sensitive and high throughput determination of antioxidant activities was achieved. The spectrophotometric characterization of the microplate containing dried or fresh DPPH free radicals was reported. The response of the DPPH dry reagent array towards different standard antioxidants was studied. The reaction for DPPH in fresh or dry reagent array with Trolox was reported and compared. The DPPH dry reagent array was used to study the antioxidant activity of banana, green tea, pink guava, and honeydew and the results were compared to the samples reacted with freshly prepared DPPH. The proposed method is comparable to the classical DPPH method, more convenient, simple to operate with minimal solvent required and excellent sensitivity.

  10. Investigating the antifungal activity of TiO2 nanoparticles deposited on branched carbon nanotube arrays

    NASA Astrophysics Data System (ADS)

    Darbari, S.; Abdi, Y.; Haghighi, F.; Mohajerzadeh, S.; Haghighi, N.

    2011-06-01

    Branched carbon nanotube (CNT) arrays were synthesized by plasma-enhanced chemical vapour deposition on a silicon substrate. Ni was used as the catalyst and played an important role in the realization of branches in vertically aligned nanotubes. TiO2 nanoparticles on the branched CNTs were produced by atmospheric pressure chemical vapour deposition followed by a 500 °C annealing step. Transmission and scanning electron microscopic techniques were used to study the morphology of the TiO2/branched CNT structures while x-ray diffraction and Raman spectroscopy were used to verify the characteristics of the prepared nanostructures. Their antifungal effect on Candida albicans biofilms under visible light was investigated and compared with the activity of TiO2/CNT arrays and thin films of TiO2. The TiO2/branched CNTs showed a highly improved photocatalytic antifungal activity in comparison with the TiO2/CNTs and TiO2 film. The excellent visible light-induced photocatalytic antifungal activity of the TiO2/branched CNTs was attributed to the generation of electron-hole pairs by visible light excitation with a low recombination rate, in addition to the high surface area provided for the interaction between the cells and the nanostructures. Scanning electron microscopy was used to observe the resulting morphological changes in the cell body of the biofilms existing on the antifungal samples.

  11. Catalase-like and peroxidase-like catalytic activities of silicon nanowire arrays.

    PubMed

    Wang, Hongwei; Jiang, Wenwen; Wang, Yanwei; Liu, Xiaoli; Yao, Jianlin; Yuan, Lin; Wu, Zhaoqiang; Li, Dan; Song, Bo; Chen, Hong

    2013-01-08

    Silicon nanowire arrays (SiNWAs) were found to have catalytic activities similar to those of biological enzymes catalase and peroxidase. Thus not only can these materials catalyze the decomposition reaction of H(2)O(2) into water and oxygen, but they can also catalyze the oxidation of o-phenylenediamine (OPD), a common substrate for peroxidases, by H(2)O(2). The presence of Si-H bonds and the morphology of the SiNWAs are found to be crucial to the occurrence of such catalytic activity. When the SiNWAs are reacted with H(2)O(2), the data from Raman spectroscopy suggests the formation of (Si-H)(2)···(O species) ((Si-H)(2)···Os), which is presumably responsible for the catalytic activity. These findings suggest the potential use of SiNWAs as enzyme mimics in medicine, biotechnology, and environmental chemistry.

  12. Non-activation ZnO array as a buffering layer to fabricate strongly adhesive metal-organic framework/PVDF hollow fiber membranes.

    PubMed

    Li, Wanbin; Meng, Qin; Li, Xiaonian; Zhang, Congyang; Fan, Zheng; Zhang, Guoliang

    2014-09-04

    A non-activation (NA) ZnO array is directly grown on a PVDF hollow fiber membrane. The defect-free MOF layers can be synthesized easily on the NA-ZnO array without any activation procedure. The array and MOF layers are strongly adhered to the hollow fiber membrane. The prepared ZIF membranes exhibit excellent gas separation performances.

  13. Solar array flight experiment

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Emerging satellite designs require increasing amounts of electrical power to operate spacecraft instruments and to provide environments suitable for human habitation. In the past, electrical power was generated by covering rigid honeycomb panels with solar cells. This technology results in unacceptable weight and volume penalties when large amounts of power are required. To fill the need for large-area, lightweight solar arrays, a fabrication technique in which solar cells are attached to a copper printed circuit laminated to a plastic sheet was developed. The result is a flexible solar array with one-tenth the stowed volume and one-third the weight of comparably sized rigid arrays. An automated welding process developed to attack the cells to the printed circuit guarantees repeatable welds that are more tolerant of severe environments than conventional soldered connections. To demonstrate the flight readiness of this technology, the Solar Array Flight Experiment (SAFE) was developed and flown on the space shuttle Discovery in September 1984. The tests showed the modes and frequencies of the array to be very close to preflight predictions. Structural damping, however, was higher than anticipated. Electrical performance of the active solar panel was also tested. The flight performance and postflight data evaluation are described.

  14. Investigating microbial colonization in actively forming hydrothermal deposits using thermocouple arrays

    NASA Astrophysics Data System (ADS)

    Tivey, M. K.; Reysenbach, A. L.; Hirsch, M.; Steinberg, J.; Flores, G. E.

    2010-12-01

    Investigations of microbial colonization of very young hydrothermal deposits were carried out in 2009 at hydrothermal vents in the Lau Basin (SW Pacific), and in Guaymas Basin, Gulf of California, with a test deployment at the Rainbow vent field on the Mid-Atlantic Ridge in 2008. Our method entailed razing active chimneys and placing arrays of temperature probes (8 titanium-encased probes with their tips placed within a titanium cage) over the active flow. The chimneys that grew back through each array, encasing the temperature probe tips, were recovered after 2 to 15 days, along with temperature records. Molecular phylogenetic methods are being used to reveal the members of the microbial communities that developed in each chimney of known age and thermal history. A total of 15 array deployments were made at 10 vents in 6 different vent fields. Similar morphology beehives (with porous fine-grained interiors and steep temperature gradients across the outermost more-consolidated “wall”) formed at 2 of the 3 vents in Guaymas Basin (in 2 and 5 days at one vent and 3 and 15 days at a second), and at one vent each in the Kilo Moana (in 3 days), Tahi Moana (in 2.5 days), and Tui Malila (in 3 and 8 days) vent fields in the Lau Basin. In contrast, open conduit, thin walled chimneys grew within arrays at the Mariner vent field, Lau Basin, at 3 different vents (in 3 days at one vent, in 3 and 11 days at a second vent, and in 13 days at a third vent). A lower temperature (<280C) diffuser/spire with a filamentous biofilm formed in 15 days in an array at a hydrocarbon-rich vent in the Guaymas Basin. A similar biofilm formed after 6 days within an array placed earlier at this same vent, with little mineralization. Preliminary diversity data from the 6 and 15 day Guaymas deployments show an increased diversity of bacteria with time with initial colonizers being primarily sulfur-oxidizing Epsilonproteobacteria, with members of the Aquificales and Deltaproteobacteria appearing

  15. NASA's Spaceliner Investment Area Technology Activities

    NASA Technical Reports Server (NTRS)

    Hueter, Uwe; Lyles, Garry M. (Technical Monitor)

    2001-01-01

    NASA's has established long term goals for access-to-space. The third generation launch systems are to be fully reusable and operational around 2025. The goals for the third generation launch system are to significantly reduce cost and improve safety over current conditions. The Advanced Space Transportation Program Office (ASTP) at the NASA's Marshall Space Flight Center in Huntsville, AL has the agency lead to develop space transportation technologies. Within ASTP, under the Spaceliner Investment Area, third generation technologies are being pursued in the areas of propulsion, airframes, integrated vehicle health management (IVHM), avionics, power, operations, and range. The ASTP program will mature these technologies through both ground and flight system testing. The Spaceliner Investment Area plans to mature vehicle technologies to reduce the implementation risks for future commercially developed reusable launch vehicles (RLV). The plan is to substantially increase the design and operating margins of the third generation RLV (the Space Shuttle is the first generation) by incorporating advanced technologies in propulsion, materials, structures, thermal protection systems, avionics, and power. Advancements in design tools and better characterization of the operational environment will allow improvements in design margins. Improvements in operational efficiencies will be provided through use of advanced integrated health management, operations, and range technologies. The increase in margins will allow components to operate well below their design points resulting in improved component operating life, reliability, and safety which in turn reduces both maintenance and refurbishment costs. These technologies have the potential of enabling horizontal takeoff by reducing the takeoff weight and achieving the goal of airline-like operation. These factors in conjunction with increased flight rates from an expanding market will result in significant improvements in safety

  16. Active microelectronic array system for DNA hybridization, genotyping and pharmacogenomic applications.

    PubMed

    Sosnowski, Ron; Heller, Michael J; Tu, Eugene; Forster, Anita H; Radtkey, Ray

    2002-12-01

    Microelectronic arrays have been developed for DNA hybridization analysis of point mutations, single nucleotide polymorphisms, short tandem repeats and gene expression. In addition to a variety of molecular biology and genomic research applications, such devices will also be used for infectious disease detection, genetic and cancer diagnostics, and pharmacogenomic applications. These microelectronic array devices are able to produce defined electric fields on their surfaces that allow charged molecules and other entities to be transported to or from any test site or micro-location on the planar surface of the device. These molecules and entities include DNA, RNA, proteins, enzymes, antibodies and cells. Electronic-based molecule addressing and hybridization can then be carried out, where the electric field is now used to greatly accelerate the hybridization reactions that occur on the selected test sites. When reversed, the electric field can be used to provide an additional parameter for improved hybridization. Special low-conductance buffers have been developed that provide for the rapid transport of the DNA molecules and facilitate the electronic hybridization reactions under conditions that do not support hybridization. Important to the device function is the permeation layer that overcoats the underlying microelectrodes. Generally composed of a porous hydrogel material impregnated with attachment chemistry, this permeation layer prevents the destruction of analytes at the active microelectrode surface, ameliorates the adverse effects of electrolysis products on the sensitive hybridization and affinity reactions, and serves as a support structure for attaching DNA probes and other molecules to the array. The microelectronic chip or array device is incorporated into a cartridge package (NanoChip trade mark cartridge) that provides the electronic, optical, and fluidic interfacing. A complete instrument system (NanoChip trade mark Molecular Biology Workstation

  17. Aerospace and Flight. Technology Learning Activity. Teacher Edition. Technology Education Series.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This packet of technology learning activity (TLA) materials on aerospace and flight for students in grades 6-10 consists of a technology education overview, information on use, and instructor's and student's sections. The overview discusses the technology education program and materials. Components of the instructor's and student's sections are…

  18. Materials, devices, techniques, and applications for Z-plane focal plane array technology II; Proceedings of the Meeting, San Diego, CA, July 12, 13, 1990

    NASA Astrophysics Data System (ADS)

    Carson, John C.

    1990-11-01

    Various papers on materials, devices, techniques, and applications for X-plane focal plane array technology are presented. Individual topics addressed include: application of Z-plane technology to the remote sensing of the earth from GEO, applications of smart neuromorphic focal planes, image-processing of Z-plane technology, neural network Z-plane implementation with very high interconnection rates, using a small IR surveillance satellite for tactical applications, establishing requirements for homing applications, Z-plane technology. Also discussed are: on-array spike suppression signal processing, algorithms for on-focal-plane gamma circumvention and time-delay integration, current HYMOSS Z-technology, packaging of electrons for on- and off-FPA signal processing, space/performance qualification of tape automated bonded devices, automation in tape automated bonding, high-speed/high-volume radiometric testing of Z-technology focal planes, 128-layer HYMOSS-module fabrication issues, automation of IRFPA production processes.

  19. A new mini Ball Grid Array (mBGA) multichip module technology

    SciTech Connect

    Chanchani, R.; Treece, K.; Dressendorfer, P.

    1994-09-01

    A new die-level packaging technology, mBGA, is reported in this paper. The mBGA enables high circuit packaging density on multichip module (MCM), facilitates die testing to obtain ``known good die,`` and allows a cost effective module assembly. We have designed and fabricated a test vehicle to evaluate mBGA multichip module technology. This paper describes the mBGA technology and the test vehicle multichip module and reports preliminary results on the die test and burn-in, thermal performance and reliability studies.

  20. Effective SERS-active substrates composed of hierarchical micro/nanostructured arrays based on reactive ion etching and colloidal masks

    NASA Astrophysics Data System (ADS)

    Zhang, Honghua; Liu, Dilong; Hang, Lifeng; Li, Xinyang; Liu, Guangqiang; Cai, Weiping; Li, Yue

    2016-09-01

    A facile route has been proposed for the fabrication of morphology-controlled periodic SiO2 hierarchical micro/nanostructured arrays by reactive ion etching (RIE) using monolayer colloidal crystals as masks. By effectively controlling the experimental conditions of RIE, the morphology of a periodic SiO2 hierarchical micro/nanostructured array could be tuned from a dome-shaped one to a circular truncated cone, and finally to a circular cone. After coating a silver thin layer, these periodic micro/nanostructured arrays were used as surface-enhanced Raman scattering (SERS)-active substrates and demonstrated obvious SERS signals of 4-Aminothiophenol (4-ATP). In addition, the circular cone arrays displayed better SERS enhancement than those of the dome-shaped and circular truncated cone arrays due to the rougher surface caused by physical bombardment. After optimization of the circular cone arrays with different periodicities, an array with the periodicity of 350 nm exhibits much stronger SERS enhancement and possesses a low detection limit of 10-10 M 4-ATP. This offers a practical platform to conveniently prepare SERS-active substrates.

  1. Research on pressure tactile sensing technology based on fiber Bragg grating array

    NASA Astrophysics Data System (ADS)

    Song, Jinxue; Jiang, Qi; Huang, Yuanyang; Li, Yibin; Jia, Yuxi; Rong, Xuewen; Song, Rui; Liu, Hongbin

    2015-09-01

    A pressure tactile sensor based on the fiber Bragg grating (FBG) array is introduced in this paper, and the numerical simulation of its elastic body was implemented by finite element software (ANSYS). On the basis of simulation, fiber Bragg grating strings were implanted in flexible silicone to realize the sensor fabrication process, and a testing system was built. A series of calibration tests were done via the high precision universal press machine. The tactile sensor array perceived external pressure, which is demodulated by the fiber grating demodulation instrument, and three-dimension pictures were programmed to display visually the position and size. At the same time, a dynamic contact experiment of the sensor was conducted for simulating robot encountering other objects in the unknown environment. The experimental results show that the sensor has good linearity, repeatability, and has the good effect of dynamic response, and its pressure sensitivity was 0.03 nm/N. In addition, the sensor also has advantages of anti-electromagnetic interference, good flexibility, simple structure, low cost and so on, which is expected to be used in the wearable artificial skin in the future.

  2. The applicability of DOE solar cell and array technology to space power

    NASA Technical Reports Server (NTRS)

    Scott-Monck, J. A.; Stella, P. M.; Berman, P. A.

    1980-01-01

    An evaluation of the main terrestrial photovoltaic development projects was performed. Technologies that may have applicability to space power are identified. Where appropriate, recommendations are made for programs to capitalize on developed technology. It is concluded that while the funding expended by DOE is considerably greater than the space (NASA and DOD) budget for photovoltaics, the terrestrial goals and the means for satisfying them are sufficiently different from space needs that little direct benefit currently exists for space applications.

  3. Minimally invasive endovascular stent-electrode array for high-fidelity, chronic recordings of cortical neural activity.

    PubMed

    Oxley, Thomas J; Opie, Nicholas L; John, Sam E; Rind, Gil S; Ronayne, Stephen M; Wheeler, Tracey L; Judy, Jack W; McDonald, Alan J; Dornom, Anthony; Lovell, Timothy J H; Steward, Christopher; Garrett, David J; Moffat, Bradford A; Lui, Elaine H; Yassi, Nawaf; Campbell, Bruce C V; Wong, Yan T; Fox, Kate E; Nurse, Ewan S; Bennett, Iwan E; Bauquier, Sébastien H; Liyanage, Kishan A; van der Nagel, Nicole R; Perucca, Piero; Ahnood, Arman; Gill, Katherine P; Yan, Bernard; Churilov, Leonid; French, Christopher R; Desmond, Patricia M; Horne, Malcolm K; Kiers, Lynette; Prawer, Steven; Davis, Stephen M; Burkitt, Anthony N; Mitchell, Peter J; Grayden, David B; May, Clive N; O'Brien, Terence J

    2016-03-01

    High-fidelity intracranial electrode arrays for recording and stimulating brain activity have facilitated major advances in the treatment of neurological conditions over the past decade. Traditional arrays require direct implantation into the brain via open craniotomy, which can lead to inflammatory tissue responses, necessitating development of minimally invasive approaches that avoid brain trauma. Here we demonstrate the feasibility of chronically recording brain activity from within a vein using a passive stent-electrode recording array (stentrode). We achieved implantation into a superficial cortical vein overlying the motor cortex via catheter angiography and demonstrate neural recordings in freely moving sheep for up to 190 d. Spectral content and bandwidth of vascular electrocorticography were comparable to those of recordings from epidural surface arrays. Venous internal lumen patency was maintained for the duration of implantation. Stentrodes may have wide ranging applications as a neural interface for treatment of a range of neurological conditions.

  4. NASA's Spaceliner 100 Investment Area Technology Activities

    NASA Technical Reports Server (NTRS)

    Hueter, Uwe; Lyles, Garry M. (Technical Monitor)

    2001-01-01

    NASA's has established long term goals for access-to-space. The third generation launch systems are to be fully reusable and operational around 2025. The goals for the third generation launch system are to reduce cost by a factor of 100 and improve safety by a factor of 10,000 over current conditions. The Advanced Space Transportation Program Office (ASTP) at the NASA's Marshall Space Flight Center in Huntsville, AL has the agency lead to develop space transportation technologies. Within ASTP, under the Spaceliner100 Investment Area, third generation technologies are being pursued in the areas of propulsion, airframes, integrated vehicle health management (IVHM), launch systems, and operations and range. The ASTP program will mature these technologies through ground system testing. Flight testing where required, will be advocated on a case by case basis.

  5. Activities of the Division of Microwave Technology

    NASA Astrophysics Data System (ADS)

    Lewerentz, Birgitta

    1989-11-01

    Multistatic radar technology requirements are very high for antennas, where a maximum of flexibility is desired. Multilobes are often used, or groups of antennas which are electrically operated. Electronics and other electrical equipment were studied for supporting ionizing radiation and several forms of electromagnetic radiation. Ferrite components were studied. For microwave and optical technology, applications are reported. High effect Pulse Microwave radiation (HPM) emitting from an antenna and creating trouble in the electronic equipment, or destruction of this equipment is discussed. The defense against HPM is studied.

  6. Catalytic Activity of Ultrathin Pt Films on Aligned Carbon Nanotube Arrays

    PubMed Central

    Su, Xin; Wu, Ji; Hinds, Bruce J.

    2013-01-01

    Uniform ultrathin Pt films were electrodeposited onto an aligned array of carbon nanotubes (CNTs) for high-area chemically stable methanol fuel cell anodes. Electrochemical treatment of the graphitic CNT surfaces by diazoniumbenzoic acid allowed for uniform Pt electroplating. The mass activity of the Pt thin film can reach 400 A/g at a scan rate of 20 mV/s and in a solution of 1 M CH3OH/0.5 M H2SO4. A programmed pulse potential at 0V was also seen to nearly eliminate the effects of carbon monoxide poisoning. The mass activity of Pt for methanol oxidation can be maintained at 300 A/g for more than 3000 s, which is 19 times of that under a constant potential of 0.7 V (vs Ag/AgCl). PMID:25132685

  7. Developing an Inflatable Solar Array

    NASA Technical Reports Server (NTRS)

    Malone, Patrick K.; Jankowski, Francis J.; Williams, Geoffery T.; Vendura, George J., Jr.

    1992-01-01

    Viewgraphs describing the development of an inflatable solar array as part of the Inflatable Torus Solar Array Technology (ITSAT) program are presented. Program phases, overall and subsystem designs, and array deployment are addressed.

  8. In situ fabrication of cleavable peptide arrays on polydimethylsiloxane and applications for kinase activity assays.

    PubMed

    Chen, Huang-Han; Hsiao, Yu-Chieh; Li, Jie-Ren; Chen, Shu-Hui

    2015-03-20

    Polydimethylsiloxane (PDMS) is widely used for microfabrication and bioanalysis; however, its surface functionalization is limited due to the lack of active functional groups and incompatibility with many solvents. We presented a novel approach for in situ fabrication of cleavable peptide arrays on polydimethylsiloxane (PDMS) viatert-butyloxycarbonyl (t-Boc)/trifluoroacetic acid (TFA) chemistry using gold nanoparticles (AuNPs) as the anchor and a disulfide/amine terminated hetero-polyethylene glycol as the cleavable linker. The method was fine tuned to use reagents compatible with the PDMS. Using 5-mer pentapeptide, Trp5, as a model, step-by-step covalent coupling during the reaction cycles was monitored by Attenuated total reflectance-Fourier transform infrared spectrometer (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), or atomic force microscopy (AFM), and further confirmed by mass spectrometry (MS) detection of the cleaved peptides. Using such a method, heptapeptides of the PKA substrate, LRRASLG (Kemptide), and its point mutated analogs were fabricated in an array format for comparative studies of cAMP-dependent protein kinase (PKA) activity. Based on on-chip detection, Kemptide sequence exhibited the highest phosphorylation activity, which was detected to a 1.5-time lesser extent for the point mutated sequence (LRRGSLG) containing the recognition motif (RRXS), and was nearly undetectable for another point mutated sequence (LRLASLG) that lacked the recognition motif. These results indicate that the reported fabrication method is able to yield highly specific peptide sequences on PDMS, leading to a highly motif-sensitive enzyme activity assay.

  9. Designing Technology Activities that Teach Mathematics

    ERIC Educational Resources Information Center

    Silk, Eli M.; Higashi, Ross; Shoop, Robin; Schunn, Christian D.

    2010-01-01

    Over the past three years, the authors have conducted research in middle and high school classrooms in an effort to improve the effectiveness of robotics to teach science, technology, engineering, and mathematics (STEM) education--their focus has been on math. The authors have found that subtle changes in the design and setup of the lesson make a…

  10. Extravehicular Activity Technology Development Status and Forecast

    NASA Technical Reports Server (NTRS)

    Chullen, Cinda; Westheimer, David T.

    2011-01-01

    The goal of NASA s current EVA technology effort is to further develop technologies that will be used to demonstrate a robust EVA system that has application for a variety of future missions including microgravity and surface EVA. Overall the objectives will be to reduce system mass, reduce consumables and maintenance, increase EVA hardware robustness and life, increase crew member efficiency and autonomy, and enable rapid vehicle egress and ingress. Over the past several years, NASA realized a tremendous increase in EVA system development as part of the Exploration Technology Development Program and the Constellation Program. The evident demand for efficient and reliable EVA technologies, particularly regenerable technologies was apparent under these former programs and will continue to be needed as future mission opportunities arise. The technological need for EVA in space has been realized over the last several decades by the Gemini, Apollo, Skylab, Space Shuttle, and the International Space Station (ISS) programs. EVAs were critical to the success of these programs. Now with the ISS extension to 2028 in conjunction with a current forecasted need of at least eight EVAs per year, the EVA hardware life and limited availability of the Extravehicular Mobility Units (EMUs) will eventually become a critical issue. The current EMU has successfully served EVA demands by performing critical operations to assemble the ISS and provide repairs of satellites such as the Hubble Space Telescope. However, as the life of ISS and the vision for future mission opportunities are realized, a new EVA systems capability will be needed and the current architectures and technologies under development offer significant improvements over the current flight systems. In addition to ISS, potential mission applications include EVAs for missions to Near Earth Objects (NEO), Phobos, or future surface missions. Surface missions could include either exploration of the Moon or Mars. Providing an

  11. Rapid, Multiplexed Characterization of Shiga Toxin-Producing Escherichia coli (STEC) Isolates Using Suspension Array Technology

    PubMed Central

    Carter, John M.; Lin, Andrew; Clotilde, Laurie; Lesho, Matthew

    2016-01-01

    Molecular methods have emerged as the most reliable techniques to detect and characterize pathogenic Escherichia coli. These molecular techniques include conventional single analyte and multiplex PCR, PCR followed by microarray detection, pulsed-field gel electrophoresis (PFGE), and whole genome sequencing. The choice of methods used depends upon the specific needs of the particular study. One versatile method involves detecting serogroup-specific markers by hybridization or binding to encoded microbeads in a suspension array. This molecular serotyping method has been developed and adopted for investigating E. coli outbreaks. The major advantages of this technique are the ability to simultaneously serotype E. coli and detect the presence of virulence and pathogenicity markers. Here, we describe the development of a family of multiplex molecular serotyping methods for Shiga toxin-producing E. coli, compare their performance to traditional serotyping methods, and discuss the cost-benefit balance of these methods in the context of various food safety objectives. PMID:27242670

  12. Michrohole Arrays Drilled with Advanced Abrasive Slurry Jet Technology to Efficiently Exploit Enhanced Geothermal Systems

    SciTech Connect

    Oglesby, Kenneth; Finsterle, Stefan; Zhang, Yingqi; Pan, Lehua; Dobson, Parick; Mohan, Ram; Shoham, Ovadia; Felber, Betty; Rychel, Dwight

    2014-03-12

    This project had two major areas of research for Engineered/ Enhanced Geothermal System (EGS) development - 1) study the potential benefits from using microholes (i.e., bores with diameters less than 10.16 centimeters/ 4 inches) and 2) study FLASH ASJ to drill/ install those microbores between a well and a fracture system. This included the methods and benefits of drilling vertical microholes for exploring the EGS reservoir and for installing multiple (forming an array of) laterals/ directional microholes for creating the in-reservoir heat exchange flow paths. Significant benefit was found in utilizing small microbore sized connecting bores for EGS efficiency and project life. FLASH ASJ was deemed too complicated to optimally work in such deep reservoirs at this time.

  13. Monitoring of low-energy seismic activity in Elbrus volcanic area with the use of underground seismic array

    NASA Astrophysics Data System (ADS)

    Kovalevsky, V.; Sobisevitch, A.

    2012-04-01

    Results of experiment with underground seismic array for studying low-energy seismic activity in the Elbrus volcanic area are presented. Linear seismic array of 2.5 km aperture is created in the tunnel of Baksan neutrino observatory. Horizontal tunnel of 4.3 km length is drilled in the mount Andyrchi at a distance of 20 km from Elbrus volcano. Array includes 6 three-component seismic sensors with 24-byte recorders installed with 500 m interval one from another along the tunnel. Underground seismic array is the new instrument of geophysical observatory organized for studies of geophysical processes in the Elbrus volcanic area. The observatory equipped with modern geophysical instruments including broadband tri-axial seismometers, quartz tilt-meters, magnetic variometers, geo-acoustic sensors, hi-precision distributed thermal sensors and gravimeters. The initial analysis of seismic signals recorded by seismic array allows us to detect low-energy seismic activity in the Elbrus volcanic area beginning from the distance of 3-5 km (the faults in a vicinity of mount Andyrchi) up to 15-25 km (area of Elbrus volcano). The regional micro-earthquakes with magnitude 1-2 at the distances 50-100 km was also recorded. 2.5 km aperture of the underground linear seismic array make it possible to determine with high accuracy hypocenters of local seismic events associated with geodynamic of volcanic magmatic structures and to realize seismo-emission tomography of the active zones of Elbrus volcano.

  14. Robust site security using smart seismic array technology and multi-sensor data fusion

    NASA Astrophysics Data System (ADS)

    Hellickson, Dean; Richards, Paul; Reynolds, Zane; Keener, Joshua

    2010-04-01

    Traditional site security systems are susceptible to high individual sensor nuisance alarm rates that reduce the overall system effectiveness. Visual assessment of intrusions can be intensive and manually difficult as cameras are slewed by the system to non intrusion areas or as operators respond to nuisance alarms. Very little system intrusion performance data are available other than discrete sensor alarm indications that provide no real value. This paper discusses the system architecture, integration and display of a multi-sensor data fused system for wide area surveillance, local site intrusion detection and intrusion classification. The incorporation of a novel seismic array of smart sensors using FK Beamforming processing that greatly enhances the overall system detection and classification performance of the system is discussed. Recent test data demonstrates the performance of the seismic array within several different installations and its ability to classify and track moving targets at significant standoff distances with exceptional immunity to background clutter and noise. Multi-sensor data fusion is applied across a suite of complimentary sensors eliminating almost all nuisance alarms while integrating within a geographical information system to feed a visual-fusion display of the area being secured. Real-time sensor detection and intrusion classification data is presented within a visual-fusion display providing greatly enhanced situational awareness, system performance information and real-time assessment of intrusions and situations of interest with limited security operator involvement. This approach scales from a small local perimeter to very large geographical area and can be used across multiple sites controlled at a single command and control station.

  15. Enthalpy arrays

    PubMed Central

    Torres, Francisco E.; Kuhn, Peter; De Bruyker, Dirk; Bell, Alan G.; Wolkin, Michal V.; Peeters, Eric; Williamson, James R.; Anderson, Gregory B.; Schmitz, Gregory P.; Recht, Michael I.; Schweizer, Sandra; Scott, Lincoln G.; Ho, Jackson H.; Elrod, Scott A.; Schultz, Peter G.; Lerner, Richard A.; Bruce, Richard H.

    2004-01-01

    We report the fabrication of enthalpy arrays and their use to detect molecular interactions, including protein–ligand binding, enzymatic turnover, and mitochondrial respiration. Enthalpy arrays provide a universal assay methodology with no need for specific assay development such as fluorescent labeling or immobilization of reagents, which can adversely affect the interaction. Microscale technology enables the fabrication of 96-detector enthalpy arrays on large substrates. The reduction in scale results in large decreases in both the sample quantity and the measurement time compared with conventional microcalorimetry. We demonstrate the utility of the enthalpy arrays by showing measurements for two protein–ligand binding interactions (RNase A + cytidine 2′-monophosphate and streptavidin + biotin), phosphorylation of glucose by hexokinase, and respiration of mitochondria in the presence of 2,4-dinitrophenol uncoupler. PMID:15210951

  16. MLS student active learning within a "cloud" technology program.

    PubMed

    Tille, Patricia M; Hall, Heather

    2011-01-01

    In November 2009, the MLS program in a large public university serving a geographically large, sparsely populated state instituted an initiative for the integration of technology enhanced teaching and learning within the curriculum. This paper is intended to provide an introduction to the system requirements and sample instructional exercises used to create an active learning technology-based classroom. Discussion includes the following: 1.) define active learning and the essential components, 2.) summarize teaching methods, technology and exercises utilized within a "cloud" technology program, 3.) describe a "cloud" enhanced classroom and programming 4.) identify active learning tools and exercises that can be implemented into laboratory science programs, and 5.) describe the evaluation and assessment of curriculum changes and student outcomes. The integration of technology in the MLS program is a continual process and is intended to provide student-driven active learning experiences.

  17. Demonstration of a micromachined planar distribution network in gap waveguide technology for a linear slot array antenna at 100 GHz

    NASA Astrophysics Data System (ADS)

    Rahiminejad, S.; Zaman, A. U.; Haasl, S.; Kildal, P.-S.; Enoksson, P.

    2016-07-01

    The need for high frequency antennas is rapidly increasing with the development of new wireless rate communication technology. Planar antennas have an attractive form factor, but they require a distribution network. Microstrip technology is most commonly used at low frequency but suffers from large dielectric and ohmic losses at higher frequencies and particularly above 100 GHz. Substrate-integrated waveguides also suffer from dielectric losses. In addition, standard rectangular waveguide interfaces are inconvenient due to the four flange screws that must be tightly fastened to the antenna to avoid leakage. The current paper presents a planar slot array antenna that does not suffer from any of these problems. The distribution network is realized by micromachining using low-loss gap waveguide technology, and it can be connected to a standard rectangular waveguide flange without using any screws or additional packaging. To realize the antenna at these frequencies, it was fabricated with micromachining, which offers the required high precision, and a low-cost fabrication method. The antenna was micromachined with DRIE in two parts, one silicon-on-insulator plate and one Si plate, which were both covered with Au to achieve conductivity. The input reflection coefficient was measured to be below 10 dB over a 15.5% bandwidth, and the antenna gain was measured to be 10.4 dBi, both of which are in agreement with simulations.

  18. Bimetallic gold-silver nanoplate array as a highly active SERS substrate for detection of streptavidin/biotin assemblies.

    PubMed

    Bi, Liyan; Dong, Jian; Xie, Wei; Lu, Wenbo; Tong, Wei; Tao, Lin; Qian, Weiping

    2013-12-17

    The silver-modified gold nanoplate arrays as bimetallic surface-enhanced Raman scattering (SERS) substrates were optimized for the surface-enhanced Raman detection of streptavidin/biotin monolayer assemblies. The bimetallic gold-silver nanoplate arrays were fabricated by coating silver nanoparticles uniformly on the gold nanoplate arrays. Depending on silver nanoparticle coating, the localized surface plasmon resonance (LSPR) peak of the bimetallic gold-silver nanoplate arrays blue-shifted and broadened significantly. The common probe molecule, Niel Blue A sulfate (NBA) was used for testing the SERS activity of the bimetallic gold-silver nanoplate arrays. The SERS intensity increased with the silver nanoparticle coating, due to a large number of hot spots and nanoparticle interfaces. The platforms were tested against a monolayer of streptavidin functionalized over the bimetallic gold-silver nanoplate arrays showing that good quality spectra could be acquired with a short acquisition time. The supramolecular interaction between streptavidin (strep) and biotin showed subsequent modification of Raman spectra that implied a change of the secondary structure of the host biomolecule. And the detection concentration for biotin by this method was as low as 1.0 nM. The enhanced SERS performance of such bimetallic gold-silver nanoplate arrays could spur further interest in the integration of highly sensitive biosensors for rapid, nondestructive, and quantitative bioanalysis, particularly in microfluidics.

  19. A new active array MST radar system with enhanced capabilities for high resolution atmospheric observations

    NASA Astrophysics Data System (ADS)

    Durga rao, Meka; Jayaraman, Achuthan; Patra, Amit; Venkat Ratnam, Madineni; Narayana Rao, T.; Kamaraj, Pandian; Jayaraj, Katta; Kmv, Prasad; Kamal Kumar, J.; Raghavendra, J.; Prasad, T. Rajendra; Thriveni, A.; Yasodha, Polisetti

    2016-07-01

    A new version of the 53-MHz MST Radar, using the 1024 solid state Transmit-Receive Modules (TRM), necessary feeder network, multi-channel receiver and a modified radar controller has been established using the existing antenna array of 1024 crossed Yagis. The new system has been configured for steering the beam on a pulse-to-pulse basis in all 360o azimuth and 20o zenith angle, providing enhanced capability to study the Mesosphere-Stratosphere-Troposphere and Ionosphere. The multi channel receiver system has been designed for Spaced Antenna (SA) and Interferometry/ Iamging applications. The new system has also been configured for radiating in circular polarization for its application in the Ionosphere Incoherent Scatter mode. The new active array MST radar at Very-High-Frequency (53-MHz) located at Gadanki (13.45°N, 79.18°E), a tropical station in India, will be used to enhance the observations of winds, turbulence during the passage of convective events over the radar site as deep convection occurs very often at tropical latitudes. The new configuration with enhanced average power, beam agility with multi-channel experiments will be a potential source for studying middle atmosphere and ionosphere. In this paper, we present the system configuration, new capabilities and the first results obtained using the new version of the MST Radar.

  20. Detecting seismic activity with a covariance matrix analysis of data recorded on seismic arrays

    NASA Astrophysics Data System (ADS)

    Seydoux, L.; Shapiro, N. M.; de Rosny, J.; Brenguier, F.; Landès, M.

    2016-03-01

    Modern seismic networks are recording the ground motion continuously at the Earth's surface, providing dense spatial samples of the seismic wavefield. The aim of our study is to analyse these records with statistical array-based approaches to identify coherent time-series as a function of time and frequency. Using ideas mainly brought from the random matrix theory, we analyse the spatial coherence of the seismic wavefield from the width of the covariance matrix eigenvalue distribution. We propose a robust detection method that could be used for the analysis of weak and emergent signals embedded in background noise, such as the volcanic or tectonic tremors and local microseismicity, without any prior knowledge about the studied wavefields. We apply our algorithm to the records of the seismic monitoring network of the Piton de la Fournaise volcano located at La Réunion Island and composed of 21 receivers with an aperture of ˜15 km. This array recorded many teleseismic earthquakes as well as seismovolcanic events during the year 2010. We show that the analysis of the wavefield at frequencies smaller than ˜0.1 Hz results in detection of the majority of teleseismic events from the Global Centroid Moment Tensor database. The seismic activity related to the Piton de la Fournaise volcano is well detected at frequencies above 1 Hz.

  1. Protein-DNA array-based identification of transcription factor activities differentially regulated in obliterative bronchiolitis

    PubMed Central

    Dong, Ming; Wang, Xin; Zhao, Hong-Lin; Zhao, Yu-Xia; Jing, Ya-Qing; Yuan, Jing-Hua; Guo, Yi-Jiu; Chen, Xing-Long; Li, Ke-Qiu; Li, Guang

    2015-01-01

    Lung transplantation has already become the preferred treatment option for a variety of end-stage pulmonary failure. However the long-term results of lung transplantation are still not compelling and the major death reason is commonly due to obliterative bronchiolitis (OB) which is considered as chronic rejection presenting manifests physiologically as a progressive decline in FEV1. Transcription factors (TFs) play a key role in regulating gene expression and in providing an interconnecting regulatory between related pathway elements. Although the transcription factors are required for expression of the proinflammatory cytokines and immune proteins which are involved in obliterative bronchiolitis following lung transplantation, the alterations of the transcription factors in OB have not yet been revealed. Therefore, to investigate the alteration pattern of the transcription factors in OB, we used protein/DNA arrays. Mice orthotopic tracheal transplantation model was used in this studying. In this study, we explored the activity profiles of TFs in Protein/DNA array data of tracheal tissue in 14 and 28 day after transplanted. From a total of 345 screened TFs, we identified 42 TFs that showed associated with OB progression. Our data indicate that TFs may be potentially involved in the pathogenesis of OB, and can prevent, diagnose and treat OB after lung transplantation. In development of OB, some of the TFs may have ability to modulate the transcription of inflammatory proteins such cytokines, inflammatory enzymes and so on. PMID:26261607

  2. Active coatings technologies for tailorable military coating systems

    NASA Astrophysics Data System (ADS)

    Zunino, J. L., III

    2007-04-01

    The main objective of the U.S. Army's Active Coatings Technologies Program is to develop technologies that can be used in combination to tailor coatings for utilization on Army Materiel. The Active Coatings Technologies Program, ACT, is divided into several thrusts, including the Smart Coatings Materiel Program, Munitions Coatings Technologies, Active Sensor packages, Systems Health Monitoring, Novel Technology Development, as well as other advanced technologies. The goal of the ACT Program is to conduct research leading to the development of multiple coatings systems for use on various military platforms, incorporating unique properties such as self repair, selective removal, corrosion resistance, sensing, ability to modify coatings' physical properties, colorizing, and alerting logistics staff when tanks or weaponry require more extensive repair. A partnership between the U.S. Army Corrosion Office at Picatinny Arsenal, NJ along with researchers at the New Jersey Institute of Technology, NJ, Clemson University, SC, University of New Hampshire, NH, and University of Massachusetts (Lowell), MA, are developing the next generation of Smart Coatings Materiel via novel technologies such as nanotechnology, Micro-electromechanical Systems (MEMS), meta-materials, flexible electronics, electrochromics, electroluminescence, etc. This paper will provide the reader with an overview of the Active Coatings Technologies Program, including an update of the on-going Smart Coatings Materiel Program, its progress thus far, description of the prototype Smart Coatings Systems and research tasks as well as future nanotechnology concepts, and applications for the Department of Defense.

  3. Development of Radar Control system for Multi-mode Active Phased Array Radar for atmospheric probing

    NASA Astrophysics Data System (ADS)

    Yasodha, Polisetti; Jayaraman, Achuthan; Thriveni, A.

    2016-07-01

    Modern multi-mode active phased array radars require highly efficient radar control system for hassle free real time radar operation. The requirement comes due to the distributed architecture of the active phased array radar, where each antenna element in the array is connected to a dedicated Transmit-Receive (TR) module. Controlling the TR modules, which are generally few hundreds in number, and functioning them in synchronisation, is a huge task during real time radar operation and should be handled with utmost care. Indian MST Radar, located at NARL, Gadanki, which is established during early 90's, as an outcome of the middle atmospheric program, is a remote sensing instrument for probing the atmosphere. This radar has a semi-active array, consisting of 1024 antenna elements, with limited beam steering, possible only along the principle planes. To overcome the limitations and difficulties, the radar is being augmented into fully active phased array, to accomplish beam agility and multi-mode operations. Each antenna element is excited with a dedicated 1 kW TR module, located in the field and enables to position the radar beam within 20° conical volume. A multi-channel receiver makes the radar to operate in various modes like Doppler Beam Swinging (DBS), Spaced Antenna (SA), Frequency Domain Interferometry (FDI) etc. Present work describes the real-time radar control (RC) system for the above described active phased array radar. The radar control system consists of a Spartan 6 FPGA based Timing and Control Signal Generator (TCSG), and a computer containing the software for controlling all the subsystems of the radar during real-time radar operation and also for calibrating the radar. The main function of the TCSG is to generate the control and timing waveforms required for various subsystems of the radar. Important components of the RC system software are (i) TR module configuring software which does programming, controlling and health parameter monitoring of the

  4. Economic impact of stimulated technological activity. Part 1: Overall economic impact of technological progress: Its measurement

    NASA Technical Reports Server (NTRS)

    1971-01-01

    Investigations were performed at the national economic level to explore the aggregate effects of technological progress on economic growth. Inadequacies in existing marco-economic yardsticks forced the study to focus on the cost savings effects achieved through technological progress. The central questions discussed in this report cover: (1) role of technological progress in economic growth, (2) factors determining the rate of economic growth due to technological progress; (3) quantitative measurements of relationships between technological progress, its determinants, and subsequent economic growth; and (4) effects of research and development activities of the space program. For Part 2, see N72-32174.

  5. Real-time, multiplexed electrochemical DNA detection using an active complementary metal-oxide-semiconductor biosensor array with integrated sensor electronics.

    PubMed

    Levine, Peter M; Gong, Ping; Levicky, Rastislav; Shepard, Kenneth L

    2009-03-15

    Optical biosensing based on fluorescence detection has arguably become the standard technique for quantifying extents of hybridization between surface-immobilized probes and fluorophore-labeled analyte targets in DNA microarrays. However, electrochemical detection techniques are emerging which could eliminate the need for physically bulky optical instrumentation, enabling the design of portable devices for point-of-care applications. Unlike fluorescence detection, which can function well using a passive substrate (one without integrated electronics), multiplexed electrochemical detection requires an electronically active substrate to analyze each array site and benefits from the addition of integrated electronic instrumentation to further reduce platform size and eliminate the electromagnetic interference that can result from bringing non-amplified signals off chip. We report on an active electrochemical biosensor array, constructed with a standard complementary metal-oxide-semiconductor (CMOS) technology, to perform quantitative DNA hybridization detection on chip using targets conjugated with ferrocene redox labels. A 4 x 4 array of gold working electrodes and integrated potentiostat electronics, consisting of control amplifiers and current-input analog-to-digital converters, on a custom-designed 5 mm x 3 mm CMOS chip drive redox reactions using cyclic voltammetry, sense DNA binding, and transmit digital data off chip for analysis. We demonstrate multiplexed and specific detection of DNA targets as well as real-time monitoring of hybridization, a task that is difficult, if not impossible, with traditional fluorescence-based microarrays.

  6. Real-time, multiplexed electrochemical DNA detection using an active complementary metal-oxide-semiconductor biosensor array with integrated sensor electronics

    PubMed Central

    Levine, Peter M.; Gong, Ping; Levicky, Rastislav; Shepard, Kenneth L.

    2009-01-01

    Optical biosensing based on fluorescence detection has arguably become the standard technique for quantifying extents of hybridization between surface-immobilized probes and fluorophore-labeled analyte targets in DNA microarrays. However, electrochemical detection techniques are emerging which could eliminate the need for physically bulky optical instrumentation, enabling the design of portable devices for point-of-care applications. Unlike fluorescence detection, which can function well using a passive substrate (one without integrated electronics), multiplexed electrochemical detection requires an electronically-active substrate to analyze each array site and benefits from the addition of integrated electronic instrumentation to further reduce platform size and eliminate the electromagnetic interference that can result from bringing non-amplified signals off chip. We report on an active electrochemical biosensor array, constructed with a standard complementary metal-oxide-semiconductor (CMOS) technology, to perform quantitative DNA hybridization detection on chip using targets conjugated with ferrocene redox labels. A 4×4 array of gold working electrodes and integrated potentiostat electronics, consisting of control amplifiers and current-input analog-to-digital converters, on a custom-designed 5×3 mm2 CMOS chip drive redox reactions using cyclic voltammetry, sense DNA binding, and transmit digital data off chip for analysis. We demonstrate multiplexed and specific detection of DNA targets as well as real-time monitoring of hybridization, a task that is difficult, if not impossible, with traditional fluorescence-based microarrays. PMID:19054661

  7. Advanced Technology Development for Active Acoustic Liners

    NASA Technical Reports Server (NTRS)

    Sheplak, Mark; Cattafesta, Louis N., III; Nishida, Toshikazu; Kurdila, Andrew J.

    2001-01-01

    Objectives include: (1) Develop electro-mechanical/acoustic models of a Helmholtz resonator possessing a compliant diaphragm coupled to a piezoelectric device; (2) Design and fabricate the energy reclamation module and active Helmholtz resonator; (3) Develop and build appropriate energy reclamation/storage circuit; (4) Develop and fabricate appropriate piezoelectric shunt circuit to tune the compliance of the active Helmholtz resonator via a variable capacitor; (5) Quantify energy reclamation module efficiency in a grazing-flow plane wave tube possessing known acoustic energy input; and (6) Quantify actively tuned Helmholtz resonator performance in grazing-flow plane wave tube for a white-noise input

  8. Aftershock activity of the 2015 Gorkha, Nepal, earthquake determined using the Kathmandu strong motion seismographic array

    NASA Astrophysics Data System (ADS)

    Ichiyanagi, Masayoshi; Takai, Nobuo; Shigefuji, Michiko; Bijukchhen, Subeg; Sasatani, Tsutomu; Rajaure, Sudhir; Dhital, Megh Raj; Takahashi, Hiroaki

    2016-02-01

    The characteristics of aftershock activity of the 2015 Gorkha, Nepal, earthquake (Mw 7.8) were evaluated. The mainshock and aftershocks were recorded continuously by the international Kathmandu strong motion seismographic array operated by Hokkaido University and Tribhuvan University. Full waveform data without saturation for all events enabled us to clarify aftershock locations and decay characteristics. The aftershock distribution was determined using the estimated local velocity structure. The hypocenter distribution in the Kathmandu metropolitan region was well determined and indicated earthquakes located shallower than 12 km depth, suggesting that aftershocks occurred at depths shallower than the Himalayan main thrust fault. Although numerical investigation suggested less resolution for the depth component, the regional aftershock epicentral distribution of the entire focal region clearly indicated earthquakes concentrated in the eastern margin of the major slip region of the mainshock. The calculated modified Omori law's p value of 1.35 suggests rapid aftershock decay and a possible high temperature structure in the aftershock region.

  9. Automated co-alignment of coherent fiber laser arrays via active phase-locking.

    PubMed

    Goodno, Gregory D; Weiss, S Benjamin

    2012-07-02

    We demonstrate a novel closed-loop approach for high-precision co-alignment of laser beams in an actively phase-locked, coherently combined fiber laser array. The approach ensures interferometric precision by optically transducing beam-to-beam pointing errors into phase errors on a single detector, which are subsequently nulled by duplication of closed-loop phasing controls. Using this approach, beams from five coherent fiber tips were simultaneously phase-locked and position-locked with sub-micron accuracy. Spatial filtering of the sensed light is shown to extend the control range over multiple beam diameters by recovering spatial coherence despite the lack of far-field beam overlap.

  10. Help with Solving Technological Problems in Project Activities

    ERIC Educational Resources Information Center

    Herold, Jean-Francois; Ginestie, Jacques

    2011-01-01

    In France, project activities figure predominantly in technology education. The general idea behind learning based on project activity is to allow the pupil to get involved in the activity in question, with the pupil tackling real situations rather than ones of an abstract nature. But too often, we notice that the pedagogical strategies used by…

  11. Influence of the activator in an acrylic bone cement on an array of cement properties.

    PubMed

    Lewis, Gladius; Xu, Jie; Deb, Sanjukta; Lasa, Blanca Vázquez; Román, Julio San

    2007-06-01

    In all but one of the acrylic bone cement brands used in cemented arthroplasties, N,N-dimethyl-4-toluidine (DMPT) serves as the activator of the polymerization reaction. However, many concerns have been raised about this activator, all related to its toxicity. Thus, various workers have assessed a number of alternative activators, with two examples being N,N-dimethylamino-4-benzyl laurate (DMAL) and N,N-dimethylamino-4-benzyl oleate (DMAO). The results of limited characterization of cements that contain DMAL or DMAO have been reported in the literature. The present work is a comprehensive comparison of cements that contain one of these three activators, in which the values of a large array of their properties were determined. These properties range from the setting time and maximum exotherm temperature of the curing cement to the variation of the loss elastic modulus of the cured cement with frequency of the applied indenting force in dynamic nanoindentation tests. The present results, taken in conjunction with those presented in previous reports by the present authors and co-workers on other properties of these cements, indicate that both DMAL and DMPT are suitable alternatives to DMPT.

  12. Promoting Technology-Assisted Active Learning in Computer Science Education

    ERIC Educational Resources Information Center

    Gao, Jinzhu; Hargis, Jace

    2010-01-01

    This paper describes specific active learning strategies for teaching computer science, integrating both instructional technologies and non-technology-based strategies shown to be effective in the literature. The theoretical learning components addressed include an intentional method to help students build metacognitive abilities, as well as…

  13. Toward a typology of technology users: how older people experience technology's potential for active aging.

    PubMed

    Gjevjon, Edith Roth; Oderud, Tone; Wensaas, Gro H; Moen, Anne

    2014-01-01

    This paper outlines an emerging typology of older users of information and communication technology (ICT) to facilitate active aging. Through inductive data analysis from focus groups, iterative workshops, and personal interviews, we suggest three types of technology users. These types are "the Excluded," "the Entertained," and "the Networker." Clearly, ICT offers several benefits to those who are enthusiastic and frequent users, exemplified as the Entertained and the Networker. Hence, our findings support the notion of technology as a tool to maintain or increase an older person's engagement and activity level. Conversely, for those reluctant, uninterested, or incapable of using ICT, such potentials are limited and imply fewer opportunities for participation in activities.

  14. Microtremor Array Measurement Survey and Strong Ground Motion Observation Activities of The MarDiM (SATREPS) Project

    NASA Astrophysics Data System (ADS)

    Ozgur Citak, Seckin; Karagoz, Ozlem; Chimoto, Kosuke; Ozel, Oguz; Yamanaka, Hiroaki; Aksahin, Bengi; Arslan, Safa; Hatayama, Ken; Ohori, Michihiro; Hori, Muneo

    2015-04-01

    Since 1939, devastating earthquakes with magnitude greater than seven ruptured North Anatolian Fault (NAF) westward, starting from 1939 Erzincan (Ms=7.9) at the eastern Turkey and including the latest 1999 Izmit-Golcuk (Ms=7.4) and the Duzce (Ms=7.2) earthquakes in the eastern Marmara region, Turkey. On the other hand, the west of the Sea of Marmara an Mw7.4 earthquake ruptured the NAF' s Ganos segment in 1912. The only un-ruptured segments of the NAF in the last century are within the Sea of Marmara, and are identified as a "seismic gap" zone that its rupture may cause a devastating earthquake. In order to unravel the seismic risks of the Marmara region a comprehensive multidisciplinary research project The MarDiM project "Earthquake And Tsunami Disaster Mitigation in The Marmara Region and Disaster Education in Turkey", has already been started since 2003. The project is conducted in the framework of "Science and Technology Research Partnership for Sustainable Development (SATREPS)" sponsored by Japan Science and Technology Agency (JST) and Japan International Cooperation Agency (JICA). One of the main research field of the project is "Seismic characterization and damage prediction" which aims to improve the prediction accuracy of the estimation of the damages induced by strong ground motions and tsunamis based on reliable source parameters, detailed deep and shallow velocity structure and building data. As for detailed deep and shallow velocity structure microtremor array measurement surveys were conducted in Zeytinburnu district of Istanbul and Tekirdag province at about 81 sites on October 2013 and September 2014. Also in September 2014, 11 accelerometer units were installed mainly in public buildings in both Zeytinburnu and Tekirdag area and are currently in operation. Each accelerometer unit compose of a Network Sensor (CV-374A2) by Tokyo Sokushin, post processing PC for data storage and power supply unit. The Network Sensor (CV-374A2) consist of three servo

  15. Microtremor Array Measurement Survey and Strong Ground Motion observation activities of The SATREPS, MarDiM project -Part 2-

    NASA Astrophysics Data System (ADS)

    Citak, Seckin; Karagoz, Ozlem; Chimoto, Kosuke; Ozel, Oguz; Yamanaka, Hiroaki; Arslan, Safa; Aksahin, Bengi; Hatayama, Ken; Ohori, Michihiro; Hori, Muneo

    2016-04-01

    Since 1939, devastating earthquakes with magnitude greater than seven ruptured North Anatolian Fault (NAF) westward, starting from 1939 Erzincan (Ms=7.9) at the eastern Turkey and including the latest 1999 Izmit-Golcuk (Ms=7.4) and the Duzce (Ms=7.2) earthquakes in the eastern Marmara region, Turkey. On the other hand, the west of the Sea of Marmara an Mw7.4 earthquake ruptured the NAF' s Ganos segment in 1912. The only un-ruptured segments of the NAF in the last century are within the Sea of Marmara, and are identified as a "seismic gap" zone that its rupture may cause a devastating earthquake. In order to unravel the seismic risks of the Marmara region a comprehensive multidisciplinary research project The MarDiM project "Earthquake And Tsunami Disaster Mitigation in The Marmara Region and Disaster Education in Turkey", has already been started since 2003. The project is conducted in the framework of "Science and Technology Research Partnership for Sustainable Development (SATREPS)" sponsored by Japan Science and Technology Agency (JST) and Japan International Cooperation Agency (JICA). One of the main research field of the project is "Seismic characterization and damage prediction" which aims to improve the prediction accuracy of the estimation of the damages induced by strong ground motions and tsunamis based on reliable source parameters, detailed deep and shallow velocity structure and building data. As for detailed deep and shallow velocity structure microtremor array measurement surveys were conducted in Zeytinburnu district of Istanbul, Tekirdag, Canakkale and Edirne provinces at about 109 sites on October 2013, September 2014 and 2015. Also in September 2014, 11 accelerometer units were installed mainly in public buildings in both Zeytinburnu and Tekirdag area and are currently in operation. Each accelerometer unit compose of a Network Sensor (CV-374A) by Tokyo Sokushin, post processing PC for data storage and power supply unit. The Network Sensor (CV-374

  16. CMOS Active Pixel Sensor Technology and Reliability Characterization Methodology

    NASA Technical Reports Server (NTRS)

    Chen, Yuan; Guertin, Steven M.; Pain, Bedabrata; Kayaii, Sammy

    2006-01-01

    This paper describes the technology, design features and reliability characterization methodology of a CMOS Active Pixel Sensor. Both overall chip reliability and pixel reliability are projected for the imagers.

  17. Commercialisation of CMOS Integrated Circuit Technology in Multi-Electrode Arrays for Neuroscience and Cell-Based Biosensors

    PubMed Central

    Graham, Anthony H. D.; Robbins, Jon; Bowen, Chris R.; Taylor, John

    2011-01-01

    The adaptation of standard integrated circuit (IC) technology as a transducer in cell-based biosensors in drug discovery pharmacology, neural interface systems and electrophysiology requires electrodes that are electrochemically stable, biocompatible and affordable. Unfortunately, the ubiquitous Complementary Metal Oxide Semiconductor (CMOS) IC technology does not meet the first of these requirements. For devices intended only for research, modification of CMOS by post-processing using cleanroom facilities has been achieved. However, to enable adoption of CMOS as a basis for commercial biosensors, the economies of scale of CMOS fabrication must be maintained by using only low-cost post-processing techniques. This review highlights the methodologies employed in cell-based biosensor design where CMOS-based integrated circuits (ICs) form an integral part of the transducer system. Particular emphasis will be placed on the application of multi-electrode arrays for in vitro neuroscience applications. Identifying suitable IC packaging methods presents further significant challenges when considering specific applications. The various challenges and difficulties are reviewed and some potential solutions are presented. PMID:22163884

  18. Commercialisation of CMOS integrated circuit technology in multi-electrode arrays for neuroscience and cell-based biosensors.

    PubMed

    Graham, Anthony H D; Robbins, Jon; Bowen, Chris R; Taylor, John

    2011-01-01

    The adaptation of standard integrated circuit (IC) technology as a transducer in cell-based biosensors in drug discovery pharmacology, neural interface systems and electrophysiology requires electrodes that are electrochemically stable, biocompatible and affordable. Unfortunately, the ubiquitous Complementary Metal Oxide Semiconductor (CMOS) IC technology does not meet the first of these requirements. For devices intended only for research, modification of CMOS by post-processing using cleanroom facilities has been achieved. However, to enable adoption of CMOS as a basis for commercial biosensors, the economies of scale of CMOS fabrication must be maintained by using only low-cost post-processing techniques. This review highlights the methodologies employed in cell-based biosensor design where CMOS-based integrated circuits (ICs) form an integral part of the transducer system. Particular emphasis will be placed on the application of multi-electrode arrays for in vitro neuroscience applications. Identifying suitable IC packaging methods presents further significant challenges when considering specific applications. The various challenges and difficulties are reviewed and some potential solutions are presented.

  19. Large space system - Charged particle environment interaction technology. [effects on high voltage solar array performance

    NASA Technical Reports Server (NTRS)

    Stevens, N. J.; Roche, J. C.; Grier, N. T.

    1979-01-01

    Large high-voltage space power systems proposed for future applications in both low earth orbit and geosynchronous altitudes must operate in the space charged-particle environment with possible interactions between this environment and the high-voltage surfaces. The paper reviews the ground experimental work to provide indicators for the interactions that could exist in the space power system. A preliminary analytical model of a large space power system is constructed using the existing NASA Charging Analyzer Program, and its performance in geosynchronous orbit is evaluated. The analytical results are used to illustrate the regions where detrimental interactions could exist and to establish areas where future technology is required.

  20. Technology to promote and increase physical activity in heart failure.

    PubMed

    Franklin, Nina C

    2015-01-01

    Regular physical activity is firmly recommended as part of a multifaceted approach to heart failure (HF) self-management. Unfortunately, research indicates that most patients are less likely to engage in and adhere to such activities. The widespread use of information and communication technology tools and resources offers an innovative and potentially beneficial avenue for increasing physical activity levels in HF patients. This article presents specific ways in which advances in information and communication technologies, including Internet- and mobile-based communications, social media platforms, and self-monitoring health devices, can serve as a means to broadly promote increasing levels of physical activity to improve health outcomes in the HF population.

  1. GREENHOUSE GAS (GHG) MITIGATION AND MONITORING TECHNOLOGY PERFORMANCE: ACTIVITIES OF THE GHG TECHNOLOGY VERIFICATION CENTER

    EPA Science Inventory

    The paper discusses greenhouse gas (GHG) mitigation and monitoring technology performance activities of the GHG Technology Verification Center. The Center is a public/private partnership between Southern Research Institute and the U.S. EPA's Office of Research and Development. It...

  2. Diagnostic Care: Grade 9. Technology Learning Activity. Teacher Edition. Level 2. Technology Education Series.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This Technology Learning Activity (TLA) on exploring diagnostic care careers for Grade 9 is designed for use in eight class periods. It gives students experience in using standard health care equipment to perform basic diagnostic procedures. This teacher's edition begins with an overview of technology education. The second section describes…

  3. Therapeutic Care. Technology Learning Activity. Teacher Edition. Technology Education Series. Level 2.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This Technology Learning Activity (TLA) for exploring therapeutic care careers is designed for use in eight class periods. It exposes students to the different types of therapeutic care and helps them understand how they can be used to treat and heal. This teacher's edition begins with an overview of technology education. The second section…

  4. Room temperature detector array technology for the terahertz to far-infrared.

    SciTech Connect

    Camacho, Ryan; Shaw, Michael; Zhang, X.; Tao, Hu; Lentine, Anthony L.; Wright, Jeremy Benjamin; Shaner, Eric Arthur; Trotter, Douglas Chandler; Averitt, Richard D.; Kadlec, Emil G; Rakich, Peter T.

    2011-10-01

    Thermal detection has made extensive progress in the last 40 years, however, the speed and detectivity can still be improved. The advancement of silicon photonic microring resonators has made them intriguing for detection devices due to their small size and high quality factors. Implementing silicon photonic microring or microdisk resonators as a means of a thermal detector gives rise to higher speed and detectivity, as well as lower noise compared to conventional devices with electrical readouts. This LDRD effort explored the design and measurements of silicon photonic microdisk resonators used for thermal detection. The characteristic values, consisting of the thermal time constant ({tau} {approx} 2 ms) and noise equivalent power were measured and found to surpass the performance of the best microbolometers. Furthermore the detectivity was found to be D{sub {lambda}} = 2.47 x 10{sup 8} cm {center_dot} {radical}Hz/W at 10.6 {mu}m which is comparable to commercial detectors. Subsequent design modifications should increase the detectivity by another order of magnitude. Thermal detection in the terahertz (THz) remains underdeveloped, opening a door for new innovative technologies such as metamaterial enhanced detectors. This project also explored the use of metamaterials in conjunction with a cantilever design for detection in the THz region and demonstrated the use of metamaterials as custom thin film absorbers for thermal detection. While much work remains to integrate these technologies into a unified platform, the early stages of research show promising futures for use in thermal detection.

  5. A microreactor array for spatially resolved measurement of catalytic activity for high-throughput catalysis science

    SciTech Connect

    Kondratyuk, Petro; Gumuslu, Gamze; Shukla, Shantanu; Miller, James B; Morreale, Bryan D; Gellman, Andrew J

    2013-04-01

    We describe a 100 channel microreactor array capable of spatially resolved measurement of catalytic activity across the surface of a flat substrate. When used in conjunction with a composition spread alloy film (CSAF, e.g. Pd{sub x}Cu{sub y}Au{sub 1-x-y}) across which component concentrations vary smoothly, such measurements permit high-throughput analysis of catalytic activity and selectivity as a function of catalyst composition. In the reported implementation, the system achieves spatial resolution of 1 mm{sup 2} over a 10×10 mm{sup 2} area. During operation, the reactant gases are delivered at constant flow rate to 100 points of differing composition on the CSAF surface by means of a 100-channel microfluidic device. After coming into contact with the CSAF catalyst surface, the product gas mixture from each of the 100 points is withdrawn separately through a set of 100 isolated channels for analysis using a mass spectrometer. We demonstrate the operation of the device on a Pd{sub x}Cu{sub y}Au{sub 1-x-y} CSAF catalyzing the H{sub 2}-D{sub 2} exchange reaction at 333 K. In essentially a single experiment, we measured the catalytic activity over a broad swathe of concentrations from the ternary composition space of the Pd{sub x}Cu{sub y}Au{sub 1-x-y} alloy.

  6. Antibacterial ability and angiogenic activity of Cu-Ti-O nanotube arrays.

    PubMed

    Zong, Mingxiang; Bai, Long; Liu, Yanlian; Wang, Xin; Zhang, Xiangyu; Huang, Xiaobo; Hang, Ruiqiang; Tang, Bin

    2017-02-01

    Bacterial infection and loosening of orthopedic implants remain two disastrously postoperative complications. Angiogenesis is critical important to facilitate implant osseointegration in vivo. TiO2 nanotubes arrays (NTAs) with proper dimensions possess good osseointegration ability. Accordingly, the present work incorporated copper (Cu) into TiO2 NTAs (Cu-Ti-O NTAs) to enhance their antibacterial ability and angiogenesis activity, which was realized through anodizing magnetron-sputtered TiCu coatings with different Cu contents on pure titanium (Ti). Our results show ordered Cu-Ti-O NTAs can be produced under proper Cu content (<15.14%) in TiCu coatings. The NTAs possess excellent long-term antibacterial ability against Staphylococcus aureus (S. aureus), which may be ascribed to sustained release of Cu(2+). The cytotoxicity of Cu-Ti-O NTAs to endothelial cells (ECs) could be negligible and can even promote cell proliferation as revealed by live/dead staining and MTT. Meanwhile, Cu-Ti-O NTAs can up-regulate nitric oxide (NO) synthesis and vascular endothelial growth factors (VEGF) secretion of ECs on the sample surfaces compared with that of pure TiO2 NTAs (control). Furthermore, the angiogenic activity is also enhanced in ionic extracts of Cu-Ti-O NTAs compared with the control. The excellent long-term antibacterial ability and favorable angiogenic activity render Cu-Ti-O NTAs to be promising implant coatings.

  7. Monitoring Hippocampus Electrical Activity In Vitro on an Elastically Deformable Microelectrode Array

    PubMed Central

    Yu, Zhe; Graudejus, Oliver; Tsay, Candice; Lacour, Stéphanie P.; Wagner, Sigurd

    2009-01-01

    Abstract Interfacing electronics and recording electrophysiological activity in mechanically active biological tissues is challenging. This challenge extends to recording neural function of brain tissue in the setting of traumatic brain injury (TBI), which is caused by rapid (within hundreds of milliseconds) and large (greater than 5% strain) brain deformation. Interfacing electrodes must be biocompatible on multiple levels and should deform with the tissue to prevent additional mechanical damage. We describe an elastically stretchable microelectrode array (SMEA) that is capable of undergoing large, biaxial, 2-D stretch while remaining functional. The new SMEA consists of elastically stretchable thin metal films on a silicone membrane. It can stimulate and detect electrical activity from cultured brain tissue (hippocampal slices), before, during, and after large biaxial deformation. We have incorporated the SMEA into a well-characterized in vitro TBI research platform, which reproduces the biomechanics of TBI by stretching the SMEA and the adherent brain slice culture. Mechanical injury parameters, such as strain and strain rate, can be precisely controlled to generate specific levels of damage. The SMEA allowed for quantification of neuronal function both before and after injury, without breaking culture sterility or repositioning the electrodes for the injury event, thus enabling serial and long-term measurements. We report tests of the SMEA and an initial application to study the effect of mechanical stimuli on neuron function, which could be employed as a high-content, drug-screening platform for TBI. PMID:19594385

  8. Diversity, genetic mapping, and signatures of domestication in the carrot (Daucus carota L.) genome, as revealed by Diversity Arrays Technology (DArT) markers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Carrot is one of the most economically important vegetables worldwide, however, genetic and genomic resources supporting carrot breeding remain limited. We developed a Diversity Arrays Technology (DArT) platform for wild and cultivated carrot and used it to investigate genetic diversity and to devel...

  9. The aircraft energy efficiency active controls technology program

    NASA Technical Reports Server (NTRS)

    Hood, R. V., Jr.

    1977-01-01

    Broad outlines of the NASA Aircraft Energy Efficiency Program for expediting the application of active controls technology to civil transport aircraft are presented. Advances in propulsion and airframe technology to cut down on fuel consumption and fuel costs, a program for an energy-efficient transport, and integrated analysis and design technology in aerodynamics, structures, and active controls are envisaged. Fault-tolerant computer systems and fault-tolerant flight control system architectures are under study. Contracts with leading manufacturers for research and development work on wing-tip extensions and winglets for the B-747, a wing load alleviation system, elastic mode suppression, maneuver-load control, and gust alleviation are mentioned.

  10. Positive Technology for Healthy Living and Active Ageing.

    PubMed

    Riva, Giuseppe; Gaggioli, Andrea; Villani, Daniela; Cipresso, Pietro; Repetto, Claudia; Serino, Silvia; Triberti, Stefano; Brivio, Eleonora; Galimberti, Carlo; Graffigna, Guendalina

    2014-01-01

    Information and communication technologies are widely and rapidly spreading in people's daily lives. But what is the possible role of the mass proliferation of digital devices in supporting healthy living and active ageing? Are they useful in fostering personal growth and individual integration of the elderly, by promoting satisfaction, opportunities for action, and self-expression? Rather, do they enhance automation, impose constraints on personal initiative, and result in compulsive consumption of information? In this chapter, we suggest that possible answers to these questions will be offered by the "Positive Technology" approach, i.e., the scientific and applied approach to using technology so that it improves the quality of our personal experiences through its structuring, augmentation, and/or replacement. First, we suggest that it is possible to use technology to manipulate the quality of experience with the goal of increasing wellness and generating strengths and resilience in individuals, organizations, and society. Then, we classify positive technologies according to their effects on these three features of personal experience - Hedonic: technologies used to induce positive and pleasant experiences; Eudaimonic: technologies used to support individuals in reaching engaging and self-actualizing experiences; Social/Interpersonal: technologies used to support and improve the connectedness between individuals, groups, and organizations. Finally, we discuss the possible role of positive technologies for healthy living and active ageing by presenting different practical applications of this approach.

  11. Progress of the Mars Array Technology Experiment (MATE) on the '01 Lander

    NASA Technical Reports Server (NTRS)

    Scheiman, D. A.; Baraona, C. R.; Jenkins, P.; Wilt, D.; Krasowski, M.; Greer, L.; Lekki, J.; Spina, D.

    1999-01-01

    Future missions to Mars will rely heavily on solar power from the sun, various solar cell types and structures must be evaluated to find the optimum. Sunlight on the surface of Mars is altered by air-borne dust that fluctuates in density from day to day. The dust affects both the intensity and spectral content of the sunlight. The MATE flight experiment was designed for this purpose and will fly on the Mars 2001 Surveyor Lander as part of the Mars In-Situ Propellant Production Precursor (MIP) package. MATE will measure the performance of several solar cell technologies and characterize the Martian environment in terms of solar power. This will be done by measuring full IV curves on solar cells, direct and global insolation, temperature, and spectral content. The Lander is is scheduled to launch in April 2001 and arrive on Mars in January of 2002. The site location has not been identified but will be near the equator and last from 100 to 300 days. The intent of this of this paper is to describe and update the progress on MATE. MATE has four main objectives for its mission to Mars. First is to measure the performance of solar cells daily on the surface of Mars, this will determine the day to day fluctuations in sunlight and temperature and provide a nominal power output. Second, in addition to measuring solar cell performance, it will allow for an intercomparison of different solar cell technologies. Third, It will study the long term effects of dust on the solar cells. Fourth and last, it will characterize the mars environment as viewed by the solar cell, measuring spectrum, insolation, and temperature. Additional information is contained in the original extended abstract.

  12. Simultaneous Solar Maximum Mission (SMM) and Very Large Array (VLA) observations of solar active regions

    NASA Technical Reports Server (NTRS)

    Willson, Robert F.

    1991-01-01

    Very Large Array observations at 20 cm wavelength can detect the hot coronal plasma previously observed at soft x ray wavelengths. Thermal cyclotron line emission was detected at the apex of coronal loops where the magnetic field strength is relatively constant. Detailed comparison of simultaneous Solar Maximum Mission (SMM) Satellite and VLA data indicate that physical parameters such as electron temperature, electron density, and magnetic field strength can be obtained, but that some coronal loops remain invisible in either spectral domain. The unprecedent spatial resolution of the VLA at 20 cm wavelength showed that the precursor, impulsive, and post-flare components of solar bursts originate in nearby, but separate loops or systems of loops.. In some cases preburst heating and magnetic changes are observed from loops tens of minutes prior to the impulsive phase. Comparisons with soft x ray images and spectra and with hard x ray data specify the magnetic field strength and emission mechanism of flaring coronal loops. At the longer 91 cm wavelength, the VLA detected extensive emission interpreted as a hot 10(exp 5) K interface between cool, dense H alpha filaments and the surrounding hotter, rarefield corona. Observations at 91 cm also provide evidence for time-correlated bursts in active regions on opposite sides of the solar equator; they are attributed to flare triggering by relativistic particles that move along large-scale, otherwise-invisible, magnetic conduits that link active regions in opposite hemispheres of the Sun.

  13. Active, Non-Intrusive Inspection Technologies for Homeland Defense

    SciTech Connect

    James L. Jones

    2003-06-01

    Active, non-intrusive inspection or interrogation technologies have been used for 100 years - with the primary focus being radiographic imaging. During the last 50 years, various active interrogation systems have been investigated and most have revealed many unique and interesting capabilities and advantages that have already benefited the general public. Unfortunately, except for medical and specific industrial applications, these unique capabilities have not been widely adopted, largely due to the complexity of the technology, the overconfident reliance on passive detection systems to handle most challenges, and the unrealistic public concerns regarding radiation safety issues for a given active inspection deployment. The unique homeland security challenges facing the United States today are inviting more "out-of-the-box" solutions and are demanding the effective technological solutions that only active interrogation systems can provide. While revolutionary new solutions are always desired, these technology advancements are rare, and when found, usually take a long time to fully understand and implement for a given application. What's becoming more evident is that focusing on under-developed, but well-understood, active inspection technologies can provide many of the needed "out-of-the-box" solutions. This paper presents a brief historical overview of active interrogation. It identifies some of the major homeland defense challenges being confronted and the commercial and research technologies presently available and being pursued. Finally, the paper addresses the role of the Idaho National Engineering and Environmental Laboratory and its partner, the Idaho Accelerator Center at Idaho State University, in promoting and developing active inspection technologies for homeland defense.

  14. Progress of the Mars Array Technology Experiment (MATE) on the 2001 Lander

    NASA Technical Reports Server (NTRS)

    Scheiman, David A.; Baraona, Cosmo; Wilt, Dave; Jenkins, Phil; Krasowski, Michael; Greer, Lawrence; Lekki, John; Spina, Daniel; Landis, Geoff

    2005-01-01

    NASA is planning missions to Mars every two years until 2010, these missions will rely on solar power. Sunlight on the surface of Mars is altered by airborne dust and fluctuates from day to day. The MATE flight experiment was designed to evaluate solar cell performance and will fly on the Mars 2001 surveyor Lander as part of the Mars In-Situ Propellant Production Precursor (MIP) package. MATE will measure several solar cell technologies and characterize the Martian environment's solar power. This will be done by measuring full IV curvers on solar cells, direct and global insolation, temperature, and spectral content. The lander is scheduled to launch in April 2001 and arrive on Mars in January of 2002. The site location has not been identified but will be near the equator, is a powered landing, and is baselined for 90 sols. The intent of this paper is to provide a brief overview of the MATE experiment and progress to date. The MATE Development Unit (DU) hardware has been built and has completed testing, work is beginning in the Qualification Unit which will start testing later this year, Flight Hardware is to be delivered next spring.

  15. Radiation protection in radiologic technology: Apathy versus active involvement

    SciTech Connect

    Franz, K.H.

    1982-11-01

    The lack of active participation in radiation protection is a serious problem in Radiologic Technology today. Underlying the problem is professional apathy. An overview of the historical changes, as well as various recent developments in radiology, accentuate the importance of necessary changes in technologists' attitudes and activities. 22 references.

  16. Nuclear Concepts & Technological Issues Institute: Teacher Activity Booklet.

    ERIC Educational Resources Information Center

    Davison, Candace C., Ed.; Lunetta, Lois W., Ed.

    For many summers the Radiation Science and Engineering Center at Pennsylvania State University has been the site of a Nuclear Concepts and Technological Issues Institute for secondary school science teachers. As a culminating activity of the institute teachers develop lesson plans, laboratory experiments, demonstrations, or other activities and…

  17. Randomly arrayed G-quadruplexes for label-free and real-time assay of enzyme activity.

    PubMed

    Liu, Zhuoliang; Li, Wang; Nie, Zhou; Peng, Feifei; Huang, Yan; Yao, Shouzhuo

    2014-07-04

    Randomly arrayed G-quadruplexes can serve as an efficient peroxidase-mimic DNAzyme and provide a novel and facile method to detect terminal deoxynucleotidyl transferase (TdT). Moreover, this G-rich sequence binding to the thioflavin T (ThT) dye can be applied in real-time fluorescent detection of TdT activity.

  18. Research and Design. Technology Learning Activity. Teacher Edition. Technology Education Series.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This curriculum guide provides technology learning activities designed to prepare students in grades 6-10 to work in the world of the future. The 8-day course provides exploratory, hands-on learning activities and information that can enhance the education of students of all types in an integrated curriculum that provides practical applications of…

  19. Modeling the Nonlinear Properties of the in vitro Hippocampal Perforant Path-Dentate System Using Multielectrode Array Technology

    PubMed Central

    Courellis, Spiros H.; Gholmieh, Ghassan I.; Marmarelis, Vasilis Z.; Berger, Theodore W.

    2009-01-01

    A modeling approach to characterize the nonlinear dynamic transformations of the dentate gyrus of the hippocampus is presented and experimentally validated. The dentate gyrus is the first region of the hippocampus which receives and integrates sensory information via the perforant path. The perforant path is composed of two distinct pathways: 1) the lateral path and 2) the medial perforant path. The proposed approach examines and captures the short-term dynamic characteristics of these two pathways using a nonparametric, third-order Poisson–Volterra model. The nonlinear characteristics of the two pathways are represented by Poisson–Volterra kernels, which are quantitative descriptors of the nonlinear dynamic transformations. The kernels were computed with experimental data from in vitro hippocampal slices. The electrophysiological activity was measured with custom-made multielectrode arrays, which allowed selective stimulation with random impulse trains and simultaneous recordings of extracellular field potential activity. The results demonstrate that this mathematically rigorous approach is suitable for the multipathway complexity of the hippocampus and yields interpretable models that have excellent predictive capabilities. The resulting models not only accurately predict previously reported electrophysiological descriptors, such as paired pulses, but more important, can be used to predict the electrophysiological activity of dentate granule cells to arbitrary stimulation patterns at the perforant path. PMID:18270006

  20. Identification of fungal pathogens in a patient with acute myelogenic leukemia using a pathogen detection array technology

    PubMed Central

    Banerjee, Sagarika; Peck, Kristen N.; Feldman, Michael D.; Schuster, Mindy G.; Alwine, James C.; Robertson, Erle S.

    2016-01-01

    ABSTRACT Invasive zygomycosis in immunocompromised patients results in a high mortality rate, and early identification is crucial to optimize therapy and to reduce morbidity. However, diagnosing specific species of zygomycetes fungi possess challenge in the clinical laboratories. A need for a rapid and sensitive diagnostic tool for early recognition of a zygomycetes fungus in clinical samples to the species level will lead to prompt and accurate therapy and the PathoChip provides one such platform. We utilized a pathogen array technology referred to as PathoChip, comprised of oligonucleotide probes that can detect all the sequenced viruses as well as known pathogenic bacteria, fungi and parasites and family-specific conserved probes, thus providing a means for detecting previously uncharacterized members of a family. We rapidly identified a zygomycetous fungus, Rhizomucor pusillus, an otherwise challenge for the clinical laboratories, predominantly in a patient with acute myelogenous leukemia. This report highlights the value of PathoChip as a diagnostic tool to identify micro-organisms to the species level, especially for those difficult to identify in most clinical laboratories. It will also help clinicians to obtain a critical snapshot of the infection profile of a patient to plan treatment strategies. PMID:26619325

  1. Packaging of an optoelectronic-VLSI chip supporting a 32 X 32 array of surface-active devices

    NASA Astrophysics Data System (ADS)

    Ayliffe, Michael H.; Rolston, D. R.; Chuah, E. L.; Bernier, Eric; Michael, Feras S. J.; Kabal, D.; Kirk, Andrew G.; Plant, David V.

    2000-05-01

    Innovative approaches to the packaging of a high-performance module accommodating a 32 X 32 array of surface-active devices indium bump bonded to a 9 X 9 mm2 VLSI chip are described. The module integrates a mini-lens array, a copper heat spreader, a thermoelectric cooler and an aluminum heatsink. The mini-lens array is aligned and packaged with the chip using a novel six degrees of freedom alignment technique. The module is compact (44 X 44 X 45 mm3), easy to assemble and can be passively removed and inserted into a free-space optical system with no need for further adjustments. The chip is mounted directly on a flexible printed-circuit board using a chip-on-board approach, providing 207 bond pad connections to the chip. The junction-to-TEC thermal resistance is only 0.4 degree(s)C/W.

  2. An investigation of signal performance enhancements achieved through innovative pixel design across several generations of indirect detection, active matrix, flat-panel arrays

    PubMed Central

    Antonuk, Larry E.; Zhao, Qihua; El-Mohri, Youcef; Du, Hong; Wang, Yi; Street, Robert A.; Ho, Jackson; Weisfield, Richard; Yao, William

    2009-01-01

    Active matrix flat-panel imager (AMFPI) technology is being employed for an increasing variety of imaging applications. An important element in the adoption of this technology has been significant ongoing improvements in optical signal collection achieved through innovations in indirect detection array pixel design. Such improvements have a particularly beneficial effect on performance in applications involving low exposures and∕or high spatial frequencies, where detective quantum efficiency is strongly reduced due to the relatively high level of additive electronic noise compared to signal levels of AMFPI devices. In this article, an examination of various signal properties, as determined through measurements and calculations related to novel array designs, is reported in the context of the evolution of AMFPI pixel design. For these studies, dark, optical, and radiation signal measurements were performed on prototype imagers incorporating a variety of increasingly sophisticated array designs, with pixel pitches ranging from 75 to 127 μm. For each design, detailed measurements of fundamental pixel-level properties conducted under radiographic and fluoroscopic operating conditions are reported and the results are compared. A series of 127 μm pitch arrays employing discrete photodiodes culminated in a novel design providing an optical fill factor of ∼80% (thereby assuring improved x-ray sensitivity), and demonstrating low dark current, very low charge trapping and charge release, and a large range of linear signal response. In two of the designs having 75 and 90 μm pitches, a novel continuous photodiode structure was found to provide fill factors that approach the theoretical maximum of 100%. Both sets of novel designs achieved large fill factors by employing architectures in which some, or all of the photodiode structure was elevated above the plane of the pixel addressing transistor. Generally, enhancement of the fill factor in either discrete or continuous

  3. Performance of Optimized Actuator and Sensor Arrays in an Active Noise Control System

    NASA Technical Reports Server (NTRS)

    Palumbo, D. L.; Padula, S. L.; Lyle, K. H.; Cline, J. H.; Cabell, R. H.

    1996-01-01

    Experiments have been conducted in NASA Langley's Acoustics and Dynamics Laboratory to determine the effectiveness of optimized actuator/sensor architectures and controller algorithms for active control of harmonic interior noise. Tests were conducted in a large scale fuselage model - a composite cylinder which simulates a commuter class aircraft fuselage with three sections of trim panel and a floor. Using an optimization technique based on the component transfer functions, combinations of 4 out of 8 piezoceramic actuators and 8 out of 462 microphone locations were evaluated against predicted performance. A combinatorial optimization technique called tabu search was employed to select the optimum transducer arrays. Three test frequencies represent the cases of a strong acoustic and strong structural response, a weak acoustic and strong structural response and a strong acoustic and weak structural response. Noise reduction was obtained using a Time Averaged/Gradient Descent (TAGD) controller. Results indicate that the optimization technique successfully predicted best and worst case performance. An enhancement of the TAGD control algorithm was also evaluated. The principal components of the actuator/sensor transfer functions were used in the PC-TAGD controller. The principal components are shown to be independent of each other while providing control as effective as the standard TAGD.

  4. Effects of surveillance towed array sensor system (SURTASS) low frequency active sonar on fish

    NASA Astrophysics Data System (ADS)

    Popper, Arthur N.; Halvorsen, Michele B.; Miller, Diane; Smith, Michael E.; Song, Jiakun; Wysocki, Lidia E.; Hastings, Mardi C.; Kane, Andrew S.; Stein, Peter

    2005-04-01

    We investigated the effects of exposure to Low Frequency Active (LFA) sonar on rainbow trout (a hearing non-specialist related to several endangered salmonids) and channel catfish (a hearing specialist), using an element of the standard SURTASS LFA source array. We measured hearing sensitivity using auditory brainstem response, effects on inner ear structure using scanning electron microscopy, effects on non-auditory tissues using general pathology and histopathology, and behavioral effects with video monitoring. Exposure to 193 dB re 1 microPa (rms received level) in the LFA frequency band for 324 seconds resulted in a TTS of 20 dB at 400 Hz in rainbow trout, with less TTS at 100 and 200 Hz. TTS in catfish ranged from 6 to 12 dB at frequencies from 200 to 1000 Hz. Both species recovered from hearing loss in several days. Inner ears sensory tissues appeared unaffected by acoustic exposure. Gross pathology indicated no damage to non-auditory tissues, including the swim bladder. Both species showed consistent startle responses at sound onsets and changed their position relative to the sound source during exposures. There was no fish death attributable to sound exposure even up to four days post-exposure. [Work supported by Chief of Naval Operations.

  5. Triboelectric active sensor array for self-powered static and dynamic pressure detection and tactile imaging.

    PubMed

    Lin, Long; Xie, Yannan; Wang, Sihong; Wu, Wenzhuo; Niu, Simiao; Wen, Xiaonan; Wang, Zhong Lin

    2013-09-24

    We report an innovative, large-area, and self-powered pressure mapping approach based on the triboelectric effect, which converts the mechanical stimuli into electrical output signals. The working mechanism of the triboelectric active sensor (TEAS) was theoretically studied by both analytical method and numerical calculation to gain an intuitive understanding of the relationship between the applied pressure and the responsive signals. Relying on the unique pressure response characteristics of the open-circuit voltage and short-circuit current, we realize both static and dynamic pressure sensing on a single device for the first time. A series of comprehensive investigations were carried out to characterize the performance of the TEAS, and high sensitivity (0.31 kPa(-1)), ultrafast response time (<5 ms), long-term stability (30,000 cycles), as well as low detection limit (2.1 Pa) were achieved. The pressure measurement range of the TEAS was adjustable, which means both gentle pressure detection and large-scale pressure sensing were enabled. Through integrating multiple TEAS units into a sensor array, the as-fabricated TEAS matrix was capable of monitoring and mapping the local pressure distribution applied on the device with distinguishable spatial profiles. This work presents a technique for tactile imaging and progress toward practical applications of nanogenerators, providing potential solutions for accomplishment of artificial skin, human-electronic interfacing, and self-powered systems.

  6. Nitrogen doped TiO2 nanotube arrays with high photoelectrochemical activity for photocatalytic applications

    NASA Astrophysics Data System (ADS)

    Yuan, Bao; Wang, Yan; Bian, Haidong; Shen, Tiankuo; Wu, Yucheng; Chen, Zhong

    2013-09-01

    Nitrogen doped TiO2 nanotube arrays (N-TNAs) were prepared by immersing TNAs in 1 M NH3·H2O solution and then annealing in different temperatures. The morphology, structure and composition of the N-TNAs were characterized by field-emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and UV-vis spectroscopy, respectively. Effects of annealing temperatures on structure, photocatalytic properties, and the crystal structure transformation process of the N-TNAs were discussed. Photocatalytic properties of the N-TNAs were evaluated in term of the degradation of methyl orange (MO) under UV light and visible light, and the photocurrent of N-TNAs were tested by electrochemical workstation. The XPS results showed that the N-TNAs were achieved by interstitial doping and substitutional doping, and the FESEM results showed the morphology was not changed after doping process. Compared with the pure TNAs, the N-TNAs annealed at 500 ̊C for 2 h with a mixed phase of anatase and rutile exhibited higher photocatalytic degradation activity to MO. Furthermore, the photocatalytic mechanism of organic pollutants degradation (MO) was discussed based on our experiments.

  7. Automated entry technologies for confined space work activities: A survey.

    PubMed

    Botti, Lucia; Ferrari, Emilio; Mora, Cristina

    2017-04-01

    Work in confined spaces poses a significant risk to workers and rescuers involved in the emergency response when an accident occurs. Despite several standards and regulations define the safety requirements for such activities, injuries, and fatalities still occur. Furthermore, the on-site inspections after accidents often reveal that both employers and employees fail to implement safe entry procedures. Removing the risk is possible by avoiding the worker entry, but many activities require the presence of the operator inside the confined space to perform manual tasks. The following study investigates the available technologies for hazardous confined space work activities, e.g., cleaning, inspecting, and maintenance tasks. The aim is to provide a systematic review of the automated solutions for high-risk activities in confined spaces, considering the non-man entry as the most effective confined space safety strategy. Second, this survey aims to provide suggestions for future research addressing the design of new technologies. The survey consists of about 60 papers concerning innovative technologies for confined space work activities. The document review shows that several solutions have been developed and automation can replace the workers for a limited number of hazardous tasks. Several activities still require the manual intervention due to the complex characteristics of confined spaces, e.g., to remove the remains of the automatic cleaning process from the bottom of a tank. The results show that available technologies require more flexibility to adapt to such occupational environments and further research is needed.

  8. High-performance, flexible, deployable array development for space applications

    NASA Technical Reports Server (NTRS)

    Gehling, Russell N.; Armstrong, Joseph H.; Misra, Mohan S.

    1994-01-01

    Flexible, deployable arrays are an attractive alternative to conventional solar arrays for near-term and future space power applications, particularly due to their potential for high specific power and low storage volume. Combined with low-cost flexible thin-film photovoltaics, these arrays have the potential to become an enabling or an enhancing technology for many missions. In order to expedite the acceptance of thin-film photovoltaics for space applications, however, parallel development of flexible photovoltaics and the corresponding deployable structure is essential. Many innovative technologies must be incorporated in these arrays to ensure a significant performance increase over conventional technologies. For example, innovative mechanisms which employ shape memory alloys for storage latches, deployment mechanisms, and array positioning gimbals can be incorporated into flexible array design with significant improvement in the areas of cost, weight, and reliability. This paper discusses recent activities at Martin Marietta regarding the development of flexible, deployable solar array technology. Particular emphasis is placed on the novel use of shape memory alloys for lightweight deployment elements to improve the overall specific power of the array. Array performance projections with flexible thin-film copper-indium-diselenide (CIS) are presented, and government-sponsored solar array programs recently initiated at Martin Marietta through NASA and Air Force Phillips Laboratory are discussed.

  9. Electronically controlled optical beam-steering by an active phased array of metallic nanoantennas.

    PubMed

    DeRose, C T; Kekatpure, R D; Trotter, D C; Starbuck, A; Wendt, J R; Yaacobi, A; Watts, M R; Chettiar, U; Engheta, N; Davids, P S

    2013-02-25

    An optical phased array of nanoantenna fabricated in a CMOS compatible silicon photonics process is presented. The optical phased array is fed by low loss silicon waveguides with integrated ohmic thermo-optic phase shifters capable of 2π phase shift with ∼ 15 mW of applied electrical power. By controlling the electrical power to the individual integrated phase shifters fixed wavelength steering of the beam emitted normal to the surface of the wafer of 8° is demonstrated for 1 × 8 phased arrays with periods of both 6 and 9 μm.

  10. NASA Stennis Space Center Test Technology Branch Activities

    NASA Technical Reports Server (NTRS)

    Solano, Wanda M.

    2000-01-01

    This paper provides a short history of NASA Stennis Space Center's Test Technology Laboratory and briefly describes the variety of engine test technology activities and developmental project initiatives. Theoretical rocket exhaust plume modeling, acoustic monitoring and analysis, hand held fire imaging, heat flux radiometry, thermal imaging and exhaust plume spectroscopy are all examples of current and past test activities that are briefly described. In addition, recent efforts and visions focused on accomodating second, third, and fourth generation flight vehicle engine test requirements are discussed.

  11. Latest developments of 10μm pitch HgCdTe diode array from the legacy to the extrinsic technology

    NASA Astrophysics Data System (ADS)

    Péré-Laperne, Nicolas; Berthoz, Jocelyn; Taalat, Rachid; Rubaldo, Laurent; Kerlain, Alexandre; Carrère, Emmanuel; Dargent, Loïc.

    2016-05-01

    Sofradir recently presented Daphnis, its latest 10 μm pitch product family. Both Daphnis XGA and HD720 are 10μm pitch mid-wave infrared focal plane array. Development of small pixel pitch is opening the way to very compact products with a high spatial resolution. This new product is taking part in the HOT technology competition allowing reductions in size, weight and power of the overall package. This paper presents the recent developments achieved at Sofradir to make the 10μm pitch HgCdTe focal plane array based on the legacy technology. Electrical and electro-optical characterizations are presented to define the appropriate design of 10μm pitch diode array. The technological tradeoffs are explained to lower the dark current, to keep high quantum efficiency with a high operability above 110K, F/4. Also, Sofradir recently achieved outstanding Modulation Transfer Function (MTF) demonstration at this pixel pitch, which clearly demonstrates the benefit to users of adopting 10μm pixel pitch focal plane array based detectors. Furthermore, the HgCdTe technology has demonstrated an increase of the operating temperature, plus 40K, moving from the legacy to the P-on-n one at a 15μm pitch in mid-wave band. The first realizations using the extrinsic P-on-n technology and the characterizations of diodes with a 10μm pitch neighborhood will be presented in both mid-wave and long-wave bands.

  12. Orthogonal electrode catheter array for mapping of endocardial focal site of ventricular activation

    SciTech Connect

    Desai, J.M.; Nyo, H.; Vera, Z.; Seibert, J.A.; Vogelsang, P.J. )

    1991-04-01

    Precise location of the endocardial site of origin of ventricular tachycardia may facilitate surgical and catheter ablation of this arrhythmia. The endocardial catheter mapping technique can locate the site of ventricular tachycardia within 4-8 cm2 of the earliest site recorded by the catheter. This report describes an orthogonal electrode catheter array (OECA) for mapping and radiofrequency ablation (RFA) of endocardial focal site of origin of a plunge electrode paced model of ventricular activation in dogs. The OECA is an 8 F five pole catheter with four peripheral electrodes and one central electrode (total surface area 0.8 cm{sup 2}). In eight mongrel dogs, mapping was performed by arbitrarily dividing the left ventricle (LV) into four segments. Each segment was mapped with OECA to find the earliest segment. Bipolar and unipolar electrograms were obtained. The plunge electrode (not visible on fluoroscopy) site was identified by the earliest wave front arrival times of -30 msec or earlier at two or more electrodes (unipolar electrograms) with reference to the earliest recorded surface ECG (I, AVF, and V1). Validation of the proximity of the five electrodes of the OECA to the plunge electrode was performed by digital radiography and RFA. Pathological examination was performed to document the proximity of the OECA to the plunge electrode and also for the width, depth, and microscopic changes of the ablation. To find the segment with the earliest LV activation a total of 10 {plus minus} 3 (mean {plus minus} SD) positions were mapped. Mean arrival times at the two earlier electrodes were -39 {plus minus} 4 msec and -35 {plus minus} 3 msec. Digital radiography showed the plunge electrode to be within the area covered by all five electrodes in all eight dogs. The plunge electrode was within 1 cm2 area of the region of RFA in all eight dogs.

  13. Active feed array compensation for reflector antenna surface distortions. Ph.D. Thesis - Akron Univ., Ohio

    NASA Technical Reports Server (NTRS)

    Acosta, Roberto J.

    1988-01-01

    The feasibility of electromagnetic compensation for reflector antenna surface distortions is investigated. The performance characteristics of large satellite communication reflector antenna systems degrade as the reflector surface distorts, mainly due to thermal effects from solar radiation. The technique developed can be used to maintain the antenna boresight directivity and sidelobe level independent of thermal effects on the reflector surface. With the advent of monolithic microwave integrated circuits (MMIC), a greater flexibility in array fed reflector antenna systems can be achieved. MMIC arrays provide independent control of amplitude and phase for each of the many radiating elements in the feed array. By assuming a known surface distortion profile, a simulation study is carried out to examine the antenna performance as a function of feed array size and number of elements. Results indicate that the compensation technique can effectively control boresight directivity and sidelobe level under peak surface distortion in the order of tenth of a wavelength.

  14. Low Frequency Activity of Cortical Networks on Microelectrode Arrays is Differentially Altered by Bicuculline and Carbaryl

    EPA Science Inventory

    Thousands of chemicals need to be characterized for their neurotoxicity potential. Neurons grown on microelectrode arrays (MEAs) are an in vitro model used to screen chemicals for functional effects on neuronal networks. Typically, after removal of low frequency components, effec...

  15. Dense arrays of micro-needles for recording and electrical stimulation of neural activity in acute brain slices

    NASA Astrophysics Data System (ADS)

    Gunning, D. E.; Beggs, J. M.; Dabrowski, W.; Hottowy, P.; Kenney, C. J.; Sher, A.; Litke, A. M.; Mathieson, K.

    2013-02-01

    Objective. This paper describes the design, microfabrication, electrical characterization and biological evaluation of a high-density micro-needle array. The array records from and electrically stimulates individual neurons simultaneously in acute slices of brain tissue. Approach. Acute slices, arguably the closest in-vitro model of the brain, have a damaged surface layer. Since electrophysiological recording methods rely heavily on electrode-cell proximity, this layer significantly attenuates the signal amplitude making the use of traditional planar electrodes unsuitable. To penetrate into the tissue, bypassing the tissue surface, and to record and stimulate neural activity in the healthy interior volume of the slice, an array of 61 micro-needles was fabricated. Main results. This device is shown to record extracellular action potentials from individual neurons in acute cortical slices with a signal to noise ratio of up to ˜15:1. Electrical stimulation of individual neurons is achieved with stimulation thresholds of 1.1-2.9 µA. Significance. The novelty of this system is the combination of close needle spacing (60 µm), needle heights of up to 250 µm and small (5-10 µm diameter) electrodes allowing the recording of single unit activity. The array is coupled to a custom-designed readout system forming a powerful electrophysiological tool that permits two-way electrode-cell communication with populations of neurons in acute brain slices.

  16. Reasoning about tasks, activities and technology to support collaboration.

    PubMed

    Watts, L A; Monk, A F

    1998-11-01

    An aspect of collaboration described as 'semi-synchronized activity' is discussed as a particular challenge for the task analysis (TA) of collaborative work. TA typically involves the decomposition of work systems into essentially independent component processes between which commodities (information or materials) pass. In collaborative work, people routinely violate the condition of independence by moving seemlessly in and out of synchronization with one another, allowing for both independent and varying levels of conjoint activity. The shift between joint and independent projects is not fixed but managed through more or less explicit awareness of the other people over time. A number of case studies of the effect of communication technologies in telemedical consultation are drawn upon to illustrate the relationship between awareness and synchronization in collaborative work. They show that an analysis of collaborative activity requires a consideration of: (1) the activities constituting work; (2) the interactions between participants required to carry out the activities; (3) who else has access to these activities besides the primary participants in the ongoing work; (4) the contemporaneity of activities; (5) the locations/environments in which the activities are carried out; and (6) the constraints that apply to accessibility and participation within and between these environments. The Comms Usage Diagram is described as a framing notation incorporating these characteristics for a broad, communications-level analysis of collaborative activity. It shows how particular technologies relate to particular phases of work, indexing their effects to collaborative activities in those contexts.

  17. Peptide array on cellulose support--a screening tool to identify peptides with dipeptidyl-peptidase IV inhibitory activity within the sequence of α-lactalbumin.

    PubMed

    Lacroix, Isabelle M E; Li-Chan, Eunice C Y

    2014-11-13

    The inhibition of the enzyme dipeptidyl-peptidase IV (DPP-IV) is an effective pharmacotherapeutic approach for the management of type 2 diabetes. Recent findings have suggested that dietary proteins, including bovine α-lactalbumin, could be precursors of peptides able to inhibit DPP-IV. However, information on the location of active peptide sequences within the proteins is far from being comprehensive. Moreover, the traditional approach to identify bioactive peptides from foods can be tedious and long. Therefore, the objective of this study was to use peptide arrays to screen α-lactalbumin-derived peptides for their interaction with DPP-IV. Deca-peptides spanning the entire α-lactalbumin sequence, with a frame shift of 1 amino acid between successive sequences, were synthesized on cellulose membranes using "SPOT" technology, and their binding to and inhibition of DPP-IV was studied. Among the 114 α-lactalbumin-derived decamers investigated, the peptides 60WCKDDQNPHS69 (αK(i) = 76 µM), 105LAHKALCSEK114 (K(i) = 217 µM) and 110LCSEKLDQWL119 (K(i) = 217 µM) were among the strongest DPP-IV inhibitors. While the SPOT- and traditionally-synthesized peptides showed consistent trends in DPP-IV inhibitory activity, the cellulose-bound peptides' binding behavior was not correlated to their ability to inhibit the enzyme. This research showed, for the first time, that peptide arrays are useful screening tools to identify DPP-IV inhibitory peptides from dietary proteins.

  18. A status of the Turbine Technology Team activities

    NASA Technical Reports Server (NTRS)

    Griffin, Lisa W.

    1992-01-01

    The recent activities of the Turbine Technology Team of the Consortium for Computational Fluid Dynamics (CFD) Application in Propulsion Technology is presented. The team consists of members from the government, industry, and universities. The goal of this team is to demonstrate the benefits to the turbine design process attainable through the application of CFD. This goal is to be achieved by enhancing and validating turbine design tools for improved loading and flowfield definition and loss prediction, and transferring the advanced technology to the turbine design process. In order to demonstrate the advantages of using CFD early in the design phase, the Space Transportation Main Engine (STME) turbines for the National Launch System (NLS) were chosen on which to focus the team's efforts. The Turbine Team activities run parallel to the STME design work.

  19. Technology Education Practical Activities for Elementary School Teachers.

    ERIC Educational Resources Information Center

    Pedras, Melvin J.; Braukmann, Jim

    This report contains four learning modules designed to support a range of objectives that include increasing technological literacy, and improving written and verbal communication skills, psychomotor skills, computational skills, geometry, analysis, problem solving, and other critical thinking skills. The activities described in each module…

  20. Learner-Interface Interaction for Technology-Enhanced Active Learning

    ERIC Educational Resources Information Center

    Sinha, Neelu; Khreisat, Laila; Sharma, Kiron

    2009-01-01

    Neelu Sinha, Laila Khreisat, and Kiron Sharma describe how learner-interface interaction promotes active learning in computer science education. In a pilot study using technology that combines DyKnow software with a hardware platform of pen-enabled HP Tablet notebook computers, Sinha, Khreisat, and Sharma created dynamic learning environments by…

  1. Office of Biological Informatics and Outreach geospatial technology activities

    USGS Publications Warehouse

    ,

    1998-01-01

    The U.S. Geological Survey (USGS) Office of Biological Informatics and Outreach (OBIO) in Reston, Virginia, and its Center for Biological Informatics (CBI) in Denver, Colorado, provide leadership in the development and use of geospatial technologies to advance the Nation's biological science activities.

  2. Student Technological Creativity Using Online Problem-Solving Activities

    ERIC Educational Resources Information Center

    Chang, Yu-Shan

    2013-01-01

    The purpose of this study was to investigate the effects of online (web-based) creative problem-solving (CPS) activities on student technological creativity and to examine the characteristics of student creativity in the context of online CPS. A pretest-posttest quasi-experiment was conducted with 107 fourth-grade students in Taiwan. The…

  3. The Secrets of the Iceman. Technology Learning Activity.

    ERIC Educational Resources Information Center

    Deal, Walter F., III

    1993-01-01

    This learning activity asks students to use critical thinking skills to imagine life in the late stone age, including the tools and technology that would have existed. Presents the context, the challenge, objectives, resources, material and equipment needs, and evaluation methods. (SK)

  4. Teaching Activities in Science/Society/Technology/Environment.

    ERIC Educational Resources Information Center

    Disinger, John F.; Lisowski, Marylin

    Developed to highlight the interrelationships between and among science, technology, society, and the environment, this guide offers educators ideas and activities, and identifies resources for instruction at the elementary and secondary school level. Introductory comments explain and support the role and importance of environmental education in…

  5. TREATABILITY STUDY BULLETIN: ENZYME-ACTIVATED CELLULOSE TECHNOLOGY - THORNECO, INC

    EPA Science Inventory

    The Enzyme-Activated Cellulose Technology developed by Thorneco, Inc. uses cellulose placed into one or more cylindrical towers to remove metals and organic compounds from an aqueous solution. The cellulose is coated with a proprietary enzyme. Operating parameters that can affe...

  6. Multispectral Detector Array Technology

    NASA Astrophysics Data System (ADS)

    Jokerst, Nan M.

    1999-12-01

    A sensor is a device used to sense or measure physical phenomena. Thus, sensors may detect electrical, mechanical, optical, chemical, tactile, or acoustic signatures of an object or scene. Objects that may be difficult to discriminate using a single sensor are often differentiated with a multiple sensor system that exploits several signature phenomena. The application of multiple sensors (and the fusion of their data) offers numerous potential performance benefits over traditional single sensor approaches. In our application, which is infrared target discrimination, employing multiple sensors, which respond to different signatures, increases the probability that a target signature will be found against a given set of weather, clutter or background noise sources. A multiple sensor system, in other words, diminishes ambiguity and uncertainty in the measured information by reducing the set of hypotheses about the target or event. Multiple sensors may also be used to reduce the vulnerability to false conclusions drawn from data of a single sensor. For instance, missiles may carry multiple sensors to better guarantee a hit or a radar can use multiple sensors to counter-jam incoming missiles.

  7. A method for reconstructing tomographic images of evoked neural activity with electrical impedance tomography using intracranial planar arrays.

    PubMed

    Aristovich, Kirill Y; dos Santos, Gustavo Sato; Packham, Brett C; Holder, David S

    2014-06-01

    A method is presented for reconstructing images of fast neural evoked activity in rat cerebral cortex recorded with electrical impedance tomography (EIT) and a 6 × 5 mm(2) epicortical planar 30 electrode array. A finite element model of the rat brain and inverse solution with Tikhonov regularization were optimized in order to improve spatial resolution and accuracy. The optimized FEM mesh had 7 M tetrahedral elements, with finer resolution (0.05 mm) near the electrodes. A novel noise-based image processing technique based on t-test significance improved depth localization accuracy from 0.5 to 0.1 mm. With the improvements, a simulated perturbation 0.5 mm in diameter could be localized in a region 4 × 5 mm(2) under the centre of the array to a depth of 1.4 mm, thus covering all six layers of the cerebral cortex with an accuracy of <0.1 mm. Simulated deep brain hippocampal or thalamic activity could be localized with an accuracy of 0.5 mm with a 256 electrode array covering the brain. Parallel studies have achieved a temporal resolution of 2 ms for imaging fast neural activity by EIT during evoked activity; this encourages the view that fast neural EIT can now resolve the propagation of depolarization-related fast impedance changes in cerebral cortex and deeper in the brain with a resolution equal or greater to the dimension of a cortical column.

  8. RADIO-SELECTED BINARY ACTIVE GALACTIC NUCLEI FROM THE VERY LARGE ARRAY STRIPE 82 SURVEY

    SciTech Connect

    Fu, Hai; Myers, A. D.; Djorgovski, S. G.; Yan, Lin; Wrobel, J. M.; Stockton, A.

    2015-01-20

    Galaxy mergers play an important role in the growth of galaxies and their supermassive black holes. Simulations suggest that tidal interactions could enhance black hole accretion, which can be tested by the fraction of binary active galactic nuclei (AGNs) among galaxy mergers. However, determining the fraction requires a statistical sample of binaries. We have identified kiloparsec-scale binary AGNs directly from high-resolution radio imaging. Inside the 92 deg{sup 2} covered by the high-resolution Very Large Array survey of the Sloan Digital Sky Survey (SDSS) Stripe 82 field, we identified 22 grade A and 30 grade B candidates of binary radio AGNs with angular separations less than 5'' (10 kpc at z = 0.1). Eight of the candidates have optical spectra for both components from the SDSS spectroscopic surveys and our Keck program. Two grade B candidates are projected pairs, but the remaining six candidates are all compelling cases of binary AGNs based on either emission line ratios or the excess in radio power compared to the Hα-traced star formation rate. Only two of the six binaries were previously discovered by an optical spectroscopic search. Based on these results, we estimate that ∼60% of our binary candidates would be confirmed once we obtain complete spectroscopic information. We conclude that wide-area high-resolution radio surveys offer an efficient method to identify large samples of binary AGNs. These radio-selected binary AGNs complement binaries identified at other wavelengths and are useful for understanding the triggering mechanisms of black hole accretion.

  9. The use of microelectrode array (MEA) to study rat peritoneal mast cell activation.

    PubMed

    Yeung, Chi-Kong; Law, Jessica Ka-Yan; Sam, Sze-Wing; Ingebrandt, Sven; Lau, Hang-Yung Alaster; Rudd, John Anthony; Chan, Mansun

    2008-06-01

    We performed this study to demonstrate the applicability of the microelectrode array (MEA) to study electrophysiological changes of rat peritoneal mast cells in the presence of compound 48/80 under normal, Ca(2+)-free, Ca(2+)-free with EDTA, and Cl(-)-free conditions. The use of high extracellular K(+) (KCl, 150 mM), charybdotoxin (ChTX, 100 nM), and Cl(-)-free containing ChTX buffers verified that the hyperpolarizing signal was due to the activation of mainly K(+) and, to a lesser extent, Cl(-) channels. Compound 48/80 concentration-dependently shortened the latent periods (the onset of response) and increased both the spatial (the K(+) and Cl(-) hyperpolarizing field potentials, HFP) and temporal measurements (the duration of response). Ca(2+)-free buffer had no effect on the latent period of compound 48/80 but increased the HFP at high concentrations. The latent period increased while the HFP diminished when cells were equilibrated in Ca(2+)-free buffer containing EDTA. Durations of the HFP were generally longer when cells were in either Ca(2+)-free or Ca(2+)-free containing EDTA buffers than when cells were in normal buffer. The EC(50) values confirmed that effects were only affected in Ca(2+)-free buffer containing EDTA but not in Ca(2+)-free or Cl(-)-free buffers, further reinforcing the hypothesis that the presence of Ca(2+) is not essential to the action of compound 48/80. The present study is the first application of MEA to study rat peritoneal mast cells, and our results indicate that it could be of value in future pharmacological research on other non-excitable cells.

  10. Significantly Enhanced Visible Light Photoelectrochemical Activity in TiO₂ Nanowire Arrays by Nitrogen Implantation.

    PubMed

    Wang, Gongming; Xiao, Xiangheng; Li, Wenqing; Lin, Zhaoyang; Zhao, Zipeng; Chen, Chi; Wang, Chen; Li, Yongjia; Huang, Xiaoqing; Miao, Ling; Jiang, Changzhong; Huang, Yu; Duan, Xiangfeng

    2015-07-08

    Titanium oxide (TiO2) represents one of most widely studied materials for photoelectrochemical (PEC) water splitting but is severely limited by its poor efficiency in the visible light range. Here, we report a significant enhancement of visible light photoactivity in nitrogen-implanted TiO2 (N-TiO2) nanowire arrays. Our systematic studies show that a post-implantation thermal annealing treatment can selectively enrich the substitutional nitrogen dopants, which is essential for activating the nitrogen implanted TiO2 to achieve greatly enhanced visible light photoactivity. An incident photon to electron conversion efficiency (IPCE) of ∼10% is achieved at 450 nm in N-TiO2 without any other cocatalyst, far exceeding that in pristine TiO2 nanowires (∼0.2%). The integration of oxygen evolution reaction (OER) cocatalyst with N-TiO2 can further increase the IPCE at 450 nm to ∼17% and deliver an unprecedented overall photocurrent density of 1.9 mA/cm(2), by integrating the IPCE spectrum with standard AM 1.5G solar spectrum. Systematic photoelectrochemical and electrochemical studies demonstrated that the enhanced PEC performance can be attributed to the significantly improved visible light absorption and more efficient charge separation. Our studies demonstrate the implantation approach can be used to reliably dope TiO2 to achieve the best performed N-TiO2 photoelectrodes to date and may be extended to fundamentally modify other semiconductor materials for PEC water splitting.

  11. Cutaneous sensory nerve as a substitute for auditory nerve in solving deaf-mutes' hearing problem: an innovation in multi-channel-array skin-hearing technology.

    PubMed

    Li, Jianwen; Li, Yan; Zhang, Ming; Ma, Weifang; Ma, Xuezong

    2014-08-15

    The current use of hearing aids and artificial cochleas for deaf-mute individuals depends on their auditory nerve. Skin-hearing technology, a patented system developed by our group, uses a cutaneous sensory nerve to substitute for the auditory nerve to help deaf-mutes to hear sound. This paper introduces a new solution, multi-channel-array skin-hearing technology, to solve the problem of speech discrimination. Based on the filtering principle of hair cells, external voice signals at different frequencies are converted to current signals at corresponding frequencies using electronic multi-channel bandpass filtering technology. Different positions on the skin can be stimulated by the electrode array, allowing the perception and discrimination of external speech signals to be determined by the skin response to the current signals. Through voice frequency analysis, the frequency range of the band-pass filter can also be determined. These findings demonstrate that the sensory nerves in the skin can help to transfer the voice signal and to distinguish the speech signal, suggesting that the skin sensory nerves are good candidates for the replacement of the auditory nerve in addressing deaf-mutes' hearing problems. Scientific hearing experiments can be more safely performed on the skin. Compared with the artificial cochlea, multi-channel-array skin-hearing aids have lower operation risk in use, are cheaper and are more easily popularized.

  12. LSA Low-cost Solar Array project

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The activities of the Low-Cost Silicon Solar Array Project during the period October through December, 1977 are reported. The LSSA Project is assigned responsibility for advancing silicon solar array technology while encouraging industry to reduce the price of arrays to a level at which photovoltaic electric power systems will be competitive with more conventional power sources early in the next decade. Set forth are the goals and plans with which the Project intends to accomplish this and the progress that was made during the quarter.

  13. Low-cost Solar Array (LSA) project

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The activities of the Low-Cost Solar Array Project are described for the period April through June 1978. The Project is assigned responsibility for advancing solar array technology while encouraging industry to reduce the price of arrays to a level at which photovoltaic electric power systems will be competitive with more conventional power sources early in the next decade. Set forth are the goals and plans with which the Project intends to accomplish this and the progress that was made during the quarter.

  14. Integrated X-ray and charged particle active pixel CMOS sensor arrays using an epitaxial silicon sensitive region

    SciTech Connect

    Kleinfelder, Stuart; Bichsel, Hans; Bieser, Fred; Matis, Howard S.; Rai, Gulshan; Retiere, Fabrice; Weiman, Howard; Yamamoto, Eugene

    2002-07-01

    Integrated CMOS Active Pixel Sensor (APS) arrays have been fabricated and tested using X-ray and electron sources. The 128 by 128 pixel arrays, designed in a standard 0.25 micron process, use a {approx}10 micron epitaxial silicon layer as a deep detection region. The epitaxial layer has a much greater thickness than the surface features used by standard CMOS APS, leading to stronger signals and potentially better signal-to-noise ratio (SNR). On the other hand, minority carriers confined within the epitaxial region may diffuse to neighboring pixels, blur images and reduce peak signal intensity. But for low-rate, sparse-event images, centroid analysis of this diffusion may be used to increase position resolution. Careful trade-offs involving pixel size and sense-node area verses capacitance must be made to optimize overall performance. The prototype sensor arrays, therefore, include a range of different pixel designs, including different APS circuits and a range of different epitaxial layer contact structures. The fabricated arrays were tested with 1.5 GeV electrons and Fe-55 X-ray sources, yielding a measured noise of 13 electrons RMS and an SNR for single Fe-55 X-rays of greater than 38.

  15. Technology in College Unions and Student Activities: A Collection of Technology Resources from the ACUI Community

    ERIC Educational Resources Information Center

    Association of College Unions International (NJ1), 2012

    2012-01-01

    This publication presents a collection of technology resources from the Association of College Unions International (ACUI) community. Contents include: (1) Podcasting (Jeff Lail); (2) Video Podcasting (Ed Cabellon); (3) Building a Multimedia Production Center (Nathan Byrer); (4) Cloud Computing in the Student Union and Student Activities (TJ…

  16. Millimeter Wave Active Sensing Technology For Self-Contained Munitions

    NASA Astrophysics Data System (ADS)

    Hunton, Andrew J.

    1983-10-01

    Active millimeter wave (MMW) sensing technology is playing an increasing role throughout the DoD research and development community in the area of Self Contained Munitions (SCM's), autonomous missiles and armament primarily intended for air and surface launched standoff antiarmor weapon systems. Each type of SCM, which requires fire-and-forget search, detection, discrimination and warhead aiming sensing functions, places varied operational, packaging and performance specifications on its MMW sensor subsystem. This paper attempts to portray the rationale for implementation of active MMW sensing devices into SCM's, along with a description of the spectrum of SCM sensor operational parameters. A treatise of active MMW sensor technologies required for ultimate successful weaponization will include discussions in the areas of signal processing and MMW RF hardware. Ultimately, as active MMW technology matures, the critical trade between complexity, cost and effectiveness must be analyzed for each SCM type. A qualitative discussion in this area will be covered as well, yielding insight into future MMW development areas which require increased heavy emphasis in order to meet the stringent requirements on SCM active MMW sensing subsystems.

  17. Active fiber optic technologies used as tamper-indicating devices

    SciTech Connect

    Horton, P.R.V.; Waddoups, I.G.

    1995-11-01

    The Sandia National Laboratories (SNL) Safeguards and Seals Evaluation Program is evaluating new fiber optic active seal technologies for use at Department of Energy (DOE) facilities. The goal of the program is to investigate active seal technologies that can monitor secured containers storing special nuclear materials (SNM) within DOE vaults. Specifically investigated were active seal technologies that can be used as tamper-indicating devices to monitor secured containers within vaults while personnel remain outside the vault area. Such a system would allow minimal access into vaults while ensuring container content accountability. The purpose of this report is to discuss tamper-indicating devices that were evaluated for possible DOE use. While previous seal evaluations (Phase I and II) considered overall facility applications, this discussion focuses specifically on their use in vault storage situations. The report will highlight general background information, specifications and requirements, and test procedures. Also discussed are the systems available from four manufacturers: Interactive Technologies, Inc., Fiber SenSys, Inc., Inovonics, Inc., and Valve Security Systems.

  18. Case study of active array feed compensation with sidelobe control for reflector surface distortion

    NASA Technical Reports Server (NTRS)

    Acosta, R. J.; Zaman, A. J. M.; Bobinsky, E. A.; Cherrette, A. R.; Lee, S. W.

    1988-01-01

    The feasibility of electromagnetically compensating for reflector surface distortions has been investigated. The performance characteristics (gain, sidelobe levels, etc.) of large communication antenna systems degrade as the reflector surface distorts mainly due to thermal effects from a varying solar flux. The techniques described in this report can be used to maintain the design performance characteristics independently of thermal effects on the reflector surface. With the advent of monolithic microwave integrated circuits (MMIC), a greater flexibility in array-fed reflector system design can be achieved. MMIC arrays provide independent control of amplitude and phase for each of many radiating elements of the feed array. It is assumed that the surface characteristics (x,y,z, its first and second derivatives) under distorted conditions are known.

  19. IN SITU REMEDIATION OF CONTAMINATED SEDIMENTS - ACTIVE CAPPING TECHNOLOGY

    SciTech Connect

    Knox, A.; Roberts, J.; Paller, M.; Reible, D.

    2010-09-02

    Active capping is a relatively new approach for treating contaminated sediments. It involves applying chemically reactive amendments to the sediment surface. The main role of active caps is to stabilize contaminants in contaminated sediments, lower the bioavailable pool of contaminants, and reduce the release of contaminants to the water column. Metals are common contaminants in many marine and fresh water environments as a result of industrial and military activities. The mobile, soluble forms of metals are generally considered toxic. Induced chemical precipitation of these metals can shift toxic metals from the aqueous phase to a solid, precipitated phase which is often less bioavailable. This approach can be achieved through application of sequestering agents such as rock phosphates, organoclays, zeolites, clay minerals, and biopolymers (e.g., chitosan) in active capping technology. Active capping holds great potential for a more permanent solution that avoids residual risks resulting from contaminant migration through the cap or breaching of the cap. In addition to identifying superior active capping agents, research is needed to optimize application techniques, application rates, and amendment combinations that maximize sequestration of contaminants. A selected set of active capping treatment technologies has been demonstrated at a few sites, including a field demonstration at the Savannah River Site, Aiken, SC. This demonstration has provided useful information on the effects of sequestering agents on metal immobilization, bioavailability, toxicity, and resistance to mechanical disturbance.

  20. [The NAS system: Nursing Activities Score in mobile technology].

    PubMed

    Catalan, Vanessa Menezes; Silveira, Denise Tolfo; Neutzling, Agnes Ludwig; Martinato, Luísa Helena Machado; Borges, Gilberto Cabral de Mello

    2011-12-01

    The objective of this study was to present the computerized structure that enables the use of the Nursing Activities Score (NAS) in mobile technology. It is a project for the development of technology production based on software engineering, founded on the theory of systems development life cycle. The NAS system was built in two modules: the search module, which is accessed using a personal computer (PC), and Data Collection module, which is accessed through a mobile device (Smartphone). The NAS system was constructed to allow other forms, in addition to the NAS tool, to be included in the future. Thus, it is understood that the development of the NAS will bring nurses closer to mobile technology and facilitate their accessibility to the data of the instrument relating to patients, thus assisting in decision-making and in staffing to provide nursing care.

  1. Understanding active and passive users: the effects of an active user using normal, hard and unreliable technologies on user assessment of trust in technology and co-user.

    PubMed

    Montague, Enid; Xu, Jie

    2012-07-01

    The aim of this study was to understand how passive users perceive the trustworthiness of active users and technologies under varying technological conditions. An experimental study was designed to vary the functioning of technologies that active users interacted with, while passive users observed these interactions. Active and passive user ratings of technology and partner were collected. Exploratory data analysis suggests that passive users developed perceptions of technologies based on the functioning of the technology and how the active user interacted with the technology. Findings from this research have implications for the design of technologies in environments where active and passive users interact with technologies in different ways. Future work in this area should explore interventions that lead to enhanced affective engagement and trust calibration.

  2. Design, evaluation and construction of TEXESS and LUXESS, and research in mini-array technology and use of data from single stations and sparse networks

    NASA Astrophysics Data System (ADS)

    Herrin, Eugene; Golden, Paul; Robertson, Herbert

    1994-10-01

    Objectives of the contract are twofold: (1) to conduct research in seismic mini-array technology & use of data from single stations & sparse networks, and (2) to design, evaluate and construct 2 mini-array, TEXESS (Texas Experimental Seismic System) in s.w. Texas and LUXESS (Luxor Experimental Seismic System), which is NE of Luxor, Egypt. These two tasks are dubbed CLIN 1 & CLIN 2. The proposed design was along the lines of a GSE Alpha Station. TEXESS was installed by SMU personnel the week of Aug 22, 1993, & the 1st event was a local, recorded on 31 Aug. With de-installation on hold until diplomatic agreements are in place between the U.S. and Egypt for the installation of LUXESS, work has been directed to CLIN 1 research; array processing, Ms:mb studies, & the AR (3) discrimination method. Research on time-domain processing of array data has resulted in a significant decrease in the standard deviation of azimuths as compared with this statistic obtained using f-k processing. The Ms:mb method is an effective and transportable discriminant for shallow events with mb greater than 4.75. Autoregressive (AR) modeling on Lg data has resulted in the ability to discriminate small economic explosions from small earthquakes.

  3. Dynamic positioning system based on active disturbance rejection technology

    NASA Astrophysics Data System (ADS)

    Lei, Zhengling; Guo, Chen; Fan, Yunsheng

    2015-08-01

    A dynamically positioned vessel, by the International Maritime Organization (IMO) and the certifying class societies (DNV, ABS, LR, etc.), is defined as a vessel that maintains its position and heading (fixed location or pre-determined track) exclusively by means of active thrusters. The development of control technology promotes the upgrading of dynamic positioning (DP) systems. Today there are two different DP systems solutions available on the market: DP system based on PID regulator and that based on model-based control. Both systems have limited disturbance rejection capability due to their design principle. In this paper, a new DP system solution is proposed based on Active Disturbance Rejection Control (ADRC) technology. This technology is composed of Tracking-Differentiator (TD), Extended State Observer (ESO) and Nonlinear Feedback Combination. On one hand, both TD and ESO can act as filters and can be used in place of conventional filters; on the other hand, the total disturbance of the system can be estimated and compensated by ESO, which therefore enhances the system's disturbance rejection capability. This technology's advantages over other methods lie in two aspects: 1) This method itself can not only achieve control objectives but also filter noisy measurements without other specialized filters; 2) This method offers a new useful approach to suppress the ocean disturbance. The simulation results demonstrate the effectiveness of the proposed method.

  4. Arrayed SU-8 polymer thermal actuators with inherent real-time feedback for actively modifying MEMS’ substrate warpage

    NASA Astrophysics Data System (ADS)

    Wang, Xinghua; Xiao, Dingbang; Chen, Zhihua; Wu, Xuezhong

    2016-09-01

    This paper describes the design, fabrication and characterization of a batch-fabricated micro-thermal actuators array with inherent real-time self-feedback, which can be used to actively modify micro-electro-mechanical systems’ (MEMS’) substrate warpage. Arrayed polymer thermal actuators utilize SU-8 polymer (a thick negative photoresist) as a functional material with integrated Ti/Al film-heaters as a microscale heat source. The electro-thermo-mechanical response of a micro-fabricated actuator was measured. The resistance of the Al/Ti film resistor varies obviously with ambient temperature, which can be used as inherent feedback for observing real-time displacement of activated SU-8 bumps (0.43 μm Ω-1). Due to the high thermal expansion coefficient, SU-8 bumps tend to have relatively large deflection at low driving voltage and are very easily integrated with MEMS devices. Experimental results indicated that the proposed SU-8 polymer thermal actuators (array) are able to achieve accurate rectification of MEMS’ substrate warpage, which might find potential applications for solving stress-induced problems in MEMS.

  5. Validation of the only commercially available immunoassay for synthetic cathinones in urine: Randox Drugs of Abuse V Biochip Array Technology.

    PubMed

    Ellefsen, Kayla N; Anizan, Sébastien; Castaneto, Marisol S; Desrosiers, Nathalie A; Martin, Thomas M; Klette, Kevin L; Huestis, Marilyn A

    2014-01-01

    Deterrence of synthetic cathinone abuse is hampered by the lack of a high-throughput immunoassay screen. The Randox Drugs of Abuse V (DOA-V) Biochip Array Technology contains two synthetic cathinone antibodies: Bath Salt I (BSI) targets mephedrone/methcathinone and Bath Salt II (BSII) targets 3',4'-methylenedioxypyrovalerone (MDPV)/3',4'-methylenedioxy-α-pyrrolidinobutiophenone (MDPBP). We evaluated DOA-V synthetic cathinones performance and conducted a full validation on the original assay with calibrators reconstituted in water, and the new assay with calibrators prepared in lyophilized urine; both utilized the same antibodies and were run on the fully automated Evidence® Analyzer. We screened 20 017 authentic military urine specimens and confirmed positives by liquid chromatography-tandem mass spectrometry (LC-MS/MS) for 28 synthetic cathinones. Limits of detection (LOD) for the original and new assays were 0.35 and 0.18 (BSI), and 8.5 and 9.2 µg/L (BSII), respectively. Linearity was acceptable (R(2)  >0.98); however, a large negative bias was observed with in-house prepared calibrators. Intra-assay imprecision was <20% BSI-II, while inter-assay imprecision was 18-42% BSI and <22% BSII. Precision was acceptable for Randox controls. Cross-reactivities of many additional synthetic cathinones were determined. Authentic drug-free negative urine pH <4 produced false positive results for BSI (6.3 µg/L) and BSII (473 µg/L). Oxidizing agents reduced BSI and increased BSII results. Sensitivity, specificity, and efficiency of 100%, 52.1%, and 53.0% were obtained at manufacturer's proposed cut-offs (BSI 5 µg/L, BSII 30 µg/L). Performance improved if cut-off concentrations increased (BSI 7.5 µg/L, BSII 40 µg/L); however, there were limited confirmed positive specimens. Currently, this is the first and only fully validated immunoassay for preliminary detection of synthetic cathinones in urine. Published 2014. This article is a U.S. Government work and is in the

  6. Active magnetic radiation shielding system analysis and key technologies.

    PubMed

    Washburn, S A; Blattnig, S R; Singleterry, R C; Westover, S C

    2015-01-01

    Many active magnetic shielding designs have been proposed in order to reduce the radiation exposure received by astronauts on long duration, deep space missions. While these designs are promising, they pose significant engineering challenges. This work presents a survey of the major systems required for such unconfined magnetic field design, allowing the identification of key technologies for future development. Basic mass calculations are developed for each system and are used to determine the resulting galactic cosmic radiation exposure for a generic solenoid design, using a range of magnetic field strength and thickness values, allowing some of the basic characteristics of such a design to be observed. This study focuses on a solenoid shaped, active magnetic shield design; however, many of the principles discussed are applicable regardless of the exact design configuration, particularly the key technologies cited.

  7. The 'Technology - Activities of Daily Living Questionnaire': a version with a technology-related subscale

    PubMed Central

    Muñoz-Neira, Carlos; López, Oscar L.; Riveros, Rodrigo; Nuñez-Huasaf, Javier; Flores, Patricia; Slachevsky, Andrea

    2016-01-01

    Background Information and communication technology (ICT) has become an increasingly important part of daily life. The ability to use technology is becoming essential for autonomous functioning in society. Current functional scales for patients with cognitive impairment do not evaluate the use of technology. The objective of this study was to develop and validate a new version of the Activities of Daily Living Questionnaire (ADLQ) that incorporates an ICT subscale. Method A new technology-based subscale was incorporated into the Spanish Version of the ADLQ (SV-ADLQ), entitled The Technology Version of the ADLQ (T-ADLQ). The T-ADLQ was administered to 63 caregivers of dementia patients, 21 proxies of mild cognitive impairment patients and 44 proxies of normal elderly subjects (mean age of the sample ± SD: 73.5 ± 8.30). We analysed the convergent validity, internal consistency, reliability cut-off point, sensitivity and specificity of the T-ADLQ. The results of the T-ADLQ were compared to the SV-ADLQ. Results The T-ADLQ showed significant correlations with the Mini-mental Test (MMSE), the Frontal Assesment Battery (FAB) as well as other measures of functional impairment and dementia severity (MMSE: r = −0.70; FAB: r = −0.65; Functional Assessment Questionnaire: r = 0.77; Instrumental Activities of Daily Living Scale: r = −0.75; Clinical Dementia Rating Scale: r = 0.72; p<0.001). The T-ADLQ showed a good reliability with a relatively high Cronbach’s alpha coefficient (Cronbach’s alpha = 0.861). When considering a functional impairment cut-off point greater than 29.25%, the sensitivity and specificity of the T-ADLQ were 82% and 90%, respectively. The area under the ROC curve (AUC) was 0.937 for the T-ADLQ and 0.932 for the original version of the test. Conclusions The T-ADLQ revealed adequate indicators of validity and reliability for the functional assessment of activities of daily living in dementia patients. However, the inclusion of technology items in

  8. Impact of active controls technology on structural integrity

    NASA Technical Reports Server (NTRS)

    Noll, Thomas; Austin, Edward; Donley, Shawn; Graham, George; Harris, Terry

    1991-01-01

    This paper summarizes the findings of The Technical Cooperation Program to assess the impact of active controls technology on the structural integrity of aeronautical vehicles and to evaluate the present state-of-the-art for predicting the loads caused by a flight-control system modification and the resulting change in the fatigue life of the flight vehicle. The potential for active controls to adversely affect structural integrity is described, and load predictions obtained using two state-of-the-art analytical methods are given.

  9. Converging micro-nano-bio technologies towards integrated in-vitro testing systems: Current activities and future challenges under the EU-Information & communication technologies program.

    PubMed

    Lymberis, A

    2010-01-01

    Interdisciplinary research towards integrated systems and their applications based on emerging convergence of information & communication technologies, micro-nano and bio technologies is expected to have a direct impact in healthcare, ageing population and well being. Micro-Nano-Bio Systems (MNBS) research and development activities under the European Union's R&D Programs, Information & Communication Technologies priority address miniaturised, smart and integrated systems for in-vitro testing (e.g. lab-on-chips) and systems interacting with the human (e.g. autonomous implants, endoscopic capsules and robotics for minimally invasive surgery). Projects addressing in-vitro testing focus on research, development and testing of technology building blocs (e.g. sample preparation technique, ultra sensitive detection technique, chemistry process for molecular recognition and microfluidics) and their integration into smart and miniaturised systems e.g. DNA & protein arrays, biochips, Lab on Chip and Lab on Card. Current challenges and developed solutions as well as open issues to fully meet technological and socioeconomic needs are presented in this paper as background introductory information to the mini-symposium on "MNBS in-vitro testing". Relevant examples of R&D within the group will be presented in the mini-symposium.

  10. Preparation and photocatalytic activity for water splitting of Pt-Na{sub 2}Ta{sub 2}O{sub 6} nanotube arrays

    SciTech Connect

    Liu, Jing; Liu, Jiawen; Li, Zhonghua

    2013-02-15

    Na{sub 2}Ta{sub 2}O{sub 6} nanotube arrays were prepared by hydrothermal method from Ta{sub 2}O{sub 5} nanotube arrays, obtained by anodization of Ta foils, in Na{sub 2}CO{sub 3} solution at 150 Degree-Sign C. The as-synthesized samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), UV-vis diffuse reflectance spectra (UV-DRS) and X-ray photoelectron spectroscopy (XPS). Analysis results show that pyrochlore structure Na{sub 2}Ta{sub 2}O{sub 6} nanotube arrays have been successfully fabricated. The diameters and lengths of Na{sub 2}Ta{sub 2}O{sub 6} nanotube arrays are 50 nm and 4 {mu}m, respectively. The photocatalytic hydrogen production activities of the as-synthesized Na{sub 2}Ta{sub 2}O{sub 6} nanotube arrays are highly dependent on the hydrothermal reaction time and Na{sub 2}CO{sub 3} concentration, optimized reaction parameters are obtained. To further improve the photocatalytic activity for hydrogen evolution, Pt loaded Na{sub 2}Ta{sub 2}O{sub 6} nanotube arrays are prepared by photochemical reduction method. The Pt loaded samples exhibit much higher activity for hydrogen evolution than pure Na{sub 2}Ta{sub 2}O{sub 6} nanotube arrays. Moreover, the photocatalytic hydrogen properties are rather stable. - Graphical abstract: Na{sub 2}Ta{sub 2}O{sub 6} nanotube arrays were synthesized by hydrothermal method using Ta{sub 2}O{sub 5} nanotube arrays as a precursor. The loaded Pt enhances the photocatalytic activity for water splitting of Na{sub 2}Ta{sub 2}O{sub 6} nanotube arrays. Highlights: Black-Right-Pointing-Pointer Novel Na{sub 2}Ta{sub 2}O{sub 6} nanotube array films with pyrochlore structure were synthesized. Black-Right-Pointing-Pointer Na{sub 2}Ta{sub 2}O{sub 6} nanotube arrays are active for H{sub 2} evolution from aqueous CH{sub 3}OH solution. Black-Right-Pointing-Pointer The effect of hydrothermal conditions on photocatalytic activity was investigated. Black-Right-Pointing-Pointer Pt loading can improve the

  11. A peptide array-based serological protein kinase A activity assay and its application in cancer diagnosis.

    PubMed

    Kong, Deok-Hoon; Jung, Se-Hui; Jeon, Hye-Yoon; Kim, Woo-Jin; Kim, Young-Myeong; Ha, Kwon-Soo

    2015-10-07

    Protein kinase A (PKA) plays a crucial role in several biological processes; however, there is no assay with sufficient sensitivity and specificity to determine serological PKA (sPKA) activity. Here we present an on-chip activity assay that employs cysteine-modified kemptide arrays to determine specific sPKA activity in human sera that eliminates the potential contributions of other kinases with a protein kinase peptide inhibitor. The sensitivity of the on-chip sPKA activity assay was greatly enhanced by Triton X-100, with a 0.01 U mL(-1) detection limit. sPKA activity was determined by subtracting nonspecific sPK activity from total sPK activity. Our assay provided greater sensitivity and specificity and more accurate area under the curve values for gastric cancer compared to the total sPK activity assay. sPKA activities in human sera from patients with hepatic (n = 30), gastric (n = 30), lung (n = 30), and colorectal (n = 30) cancers were significantly higher than those in controls (n = 30, p < 10(-4)), but no significant difference in sPKA activities between normal and inflammation groups was observed. These results demonstrate that the on-chip assay accurately measures sPKA activity in human sera and that the sPKA activity may be a potential biomarker for cancer diagnosis.

  12. Active harmonic filter technology and market assessment. Final report

    SciTech Connect

    Bhattacharya, S.; Divan, D.; Sutherland, P.

    1998-08-01

    Non-linear loads such as three-phase rectifiers, adjustable speed drives (ASDs), and arcing loads can cause voltage distortion and other power quality problems due to their interaction with the power grid. This report provides a technical and marketing assessment of active harmonic filters, a promising approach to preventing these problems at their source. Although predicting the direction and magnitude of harmonic currents is difficult due to highly interconnected nature of distribution systems, even small harmonic producing loads can result in high levels of harmonic current flow between the utility and a customer and can also cause a resonance problem at sites far removed from the harmonic producing load. The best way to keep voltage distortion low in a utility system is to constrain the harmonic currents at their sources. However, since regulation of harmonic pollution does not provide any additional value to the customer, it is unlikely that any controls will be implemented on a consistent basis in the absence of mandatory requirements. In the United States, a step toward a standard operating practice is the IEEE 519-1992 recommended harmonic standard that provides guidelines for limiting harmonic currents by industrial plants. This report identifies the equipment likely to produce harmonic loads and explains the kinds of problems that harmonic currents can cause in a utility distribution system. It describes possible solutions to these problems, including harmonic filtering and other technologies. The report examines the prospects for wider use of active harmonic filter technology and discusses the important marketing issues for potential active filter marketers and manufacturers, such as the barriers to and drivers of increased use of active filter technology and the price points for active filters.

  13. Active capping technology: a new environmental remediation of contaminated sediment.

    PubMed

    Zhang, Chang; Zhu, Meng-Ying; Zeng, Guang-Ming; Yu, Zhi-Gang; Cui, Fang; Yang, Zhong-Zhu; Shen, Liu-Qing

    2016-03-01

    The management and treatment of contaminated sediment is a worldwide problem and poses major technical and economic challenges. Nowadays, various attempts have been committed to investigating a cost-effective way in contaminated sediment restoration. Among the remediation options, in situ capping turns out to be a less expensive, less disruptive, and more durable approach. However, by using the low adsorption capacity materials, traditional caps do not always fulfill the reduction of risks that can be destructive for human health, ecosystem, and even natural resources. Active caps, therefore, are designed to employ active materials (activated carbon, apatite, zeolite, organoclay, etc.) to strengthen their adsorption and degradation capacity. The active capping technology promises to be a permanent and cost-efficient solution to contaminated sediments. This paper provides a review on the types of active materials and the ways of these active materials employed in recent active capping studies. Cap design considerations including site-specific conditions, diffusion/advection, erosive forces, and active material selection that should be noticed in an eligible remediation project are also presented.

  14. Superconducting Bolometer Array Architectures

    NASA Technical Reports Server (NTRS)

    Benford, Dominic; Chervenak, Jay; Irwin, Kent; Moseley, S. Harvey; Shafer, Rick; Staguhn, Johannes; Wollack, Ed; Oegerle, William (Technical Monitor)

    2002-01-01

    The next generation of far-infrared and submillimeter instruments require large arrays of detectors containing thousands of elements. These arrays will necessarily be multiplexed, and superconducting bolometer arrays are the most promising present prospect for these detectors. We discuss our current research into superconducting bolometer array technologies, which has recently resulted in the first multiplexed detections of submillimeter light and the first multiplexed astronomical observations. Prototype arrays containing 512 pixels are in production using the Pop-Up Detector (PUD) architecture, which can be extended easily to 1000 pixel arrays. Planar arrays of close-packed bolometers are being developed for the GBT (Green Bank Telescope) and for future space missions. For certain applications, such as a slewed far-infrared sky survey, feedhorncoupling of a large sparsely-filled array of bolometers is desirable, and is being developed using photolithographic feedhorn arrays. Individual detectors have achieved a Noise Equivalent Power (NEP) of -10(exp 17) W/square root of Hz at 300mK, but several orders of magnitude improvement are required and can be reached with existing technology. The testing of such ultralow-background detectors will prove difficult, as this requires optical loading of below IfW. Antenna-coupled bolometer designs have advantages for large format array designs at low powers due to their mode selectivity.

  15. Silicon-substrate microelectrode arrays for parallel recording of neural activity in peripheral and cranial nerves.

    PubMed

    Kovacs, G T; Storment, C W; Halks-Miller, M; Belczynski, C R; Della Santina, C C; Lewis, E R; Maluf, N I

    1994-06-01

    A new process for the fabrication of regeneration microelectrode arrays for peripheral and cranial nerve applications is presented. This type of array is implanted between the severed ends of nerves, the axons of which regenerate through via holes in the silicon and are thereafter held fixed with respect to the microelectrodes. The process described is designed for compatibility with industry-standard CMOS or BiCMOS processes (it does not involve high-temperature process steps nor heavily-doped etch-stop layers), and provides a thin membrane for the via holes, surrounded by a thick silicon supporting rim. Many basic questions remain regarding the optimum via hole and microelectrode geometries in terms of both biological and electrical performance of the implants, and therefore passive versions were fabricated as tools for addressing these issues in on-going work. Versions of the devices were implanted in the rat peroneal nerve and in the frog auditory nerve. In both cases, regeneration was verified histologically and it was observed that the regenerated nerves had reorganized into microfascicles containing both myelinated and unmyelinated axons and corresponding to the grid pattern of the via holes. These microelectrode arrays were shown to allow the recording of action potential signals in both the peripheral and cranial nerve setting, from several microelectrodes in parallel.

  16. Phased-array ultrasound technology enhances accuracy of dual frequency ultrasound measurements - towards improved ultrasound bone diagnostics.

    PubMed

    Linder, Hans; Malo, Markus K H; Liukkonen, Jukka; Jurvelin, Jukka S; Töyräs, Juha

    2016-08-01

    Overlying soft tissues attenuate ultrasound backscattered from bone, complicating diagnostics of osteoporosis at the most important fracture sites. Dual-frequency ultrasound technique (DFUS) has been proposed to solve this problem through determination of thickness and composition of overlying soft tissue. This study applies DFUS technique for the first time with a phased-array transducer to investigate if the thickness of two interfering layers (oil and water) can be accurately determined in a variety of configurations. Results indicate that DFUS may be used with phased-array ultrasound systems, making them a suitable combination to consider in future development of clinical in vivo ultrasound methodologies.

  17. Information Technology Measurement and Testing Activities at NIST

    PubMed Central

    Hogan, Michael D.; Carnahan, Lisa J.; Carpenter, Robert J.; Flater, David W.; Fowler, James E.; Frechette, Simon P.; Gray, Martha M.; Johnson, L. Arnold; McCabe, R. Michael; Montgomery, Douglas; Radack, Shirley M.; Rosenthal, Robert; Shakarji, Craig M.

    2001-01-01

    Our high technology society continues to rely more and more upon sophisticated measurements, technical standards, and associated testing activities. This was true for the industrial society of the 20th century and remains true for the information society of the 21st century. Over the last half of the 20th century, information technology (IT) has been a powerful agent of change in almost every sector of the economy. The complexity and rapidly changing nature of IT have presented unique technical challenges to the National Institute of Standards and Technology (NIST) and to the scientific measurement community in developing a sound measurement and testing infrastructure for IT. This measurement and testing infrastructure for the important non-physical and non-chemical properties associated with complex IT systems is still in an early stage of development. This paper explains key terms and concepts of IT metrology, briefly reviews the history of the National Bureau of Standards/National Institute of Standards and Technology (NBS/NIST) in the field of IT, and reviews NIST’s current capabilities and work in measurement and testing for IT. It concludes with a look at what is likely to occur in the field of IT over the next ten years and what metrology roles NIST is likely to play. PMID:27500026

  18. Information Technology Measurement and Testing Activities at NIST.

    PubMed

    Hogan, M D; Carnahan, L J; Carpenter, R J; Flater, D W; Fowler, J E; Frechette, S P; Gray, M M; Johnson, L A; McCabe, R M; Montgomery, D; Radack, S M; Rosenthal, R; Shakarji, C M

    2001-01-01

    Our high technology society continues to rely more and more upon sophisticated measurements, technical standards, and associated testing activities. This was true for the industrial society of the 20th century and remains true for the information society of the 21st century. Over the last half of the 20th century, information technology (IT) has been a powerful agent of change in almost every sector of the economy. The complexity and rapidly changing nature of IT have presented unique technical challenges to the National Institute of Standards and Technology (NIST) and to the scientific measurement community in developing a sound measurement and testing infrastructure for IT. This measurement and testing infrastructure for the important non-physical and non-chemical properties associated with complex IT systems is still in an early stage of development. This paper explains key terms and concepts of IT metrology, briefly reviews the history of the National Bureau of Standards/National Institute of Standards and Technology (NBS/NIST) in the field of IT, and reviews NIST's current capabilities and work in measurement and testing for IT. It concludes with a look at what is likely to occur in the field of IT over the next ten years and what metrology roles NIST is likely to play.

  19. Solid state active/passive night vision imager using continuous-wave laser diodes and silicon focal plane arrays

    NASA Astrophysics Data System (ADS)

    Vollmerhausen, Richard H.

    2013-04-01

    Passive imaging offers covertness and low power, while active imaging provides longer range target acquisition without the need for natural or external illumination. This paper describes a focal plane array (FPA) concept that has the low noise needed for state-of-the-art passive imaging and the high-speed gating needed for active imaging. The FPA is used with highly efficient but low-peak-power laser diodes to create a night vision imager that has the size, weight, and power attributes suitable for man-portable applications. Video output is provided in both the active and passive modes. In addition, the active mode is Class 1 eye safe and is not visible to the naked eye or to night vision goggles.

  20. ASIC Readout Circuit Architecture for Large Geiger Photodiode Arrays

    NASA Technical Reports Server (NTRS)

    Vasile, Stefan; Lipson, Jerold

    2012-01-01

    The objective of this work was to develop a new class of readout integrated circuit (ROIC) arrays to be operated with Geiger avalanche photodiode (GPD) arrays, by integrating multiple functions at the pixel level (smart-pixel or active pixel technology) in 250-nm CMOS (complementary metal oxide semiconductor) processes. In order to pack a maximum of functions within a minimum pixel size, the ROIC array is a full, custom application-specific integrated circuit (ASIC) design using a mixed-signal CMOS process with compact primitive layout cells. The ROIC array was processed to allow assembly in bump-bonding technology with photon-counting infrared detector arrays into 3-D imaging cameras (LADAR). The ROIC architecture was designed to work with either common- anode Si GPD arrays or common-cathode InGaAs GPD arrays. The current ROIC pixel design is hardwired prior to processing one of the two GPD array configurations, and it has the provision to allow soft reconfiguration to either array (to be implemented into the next ROIC array generation). The ROIC pixel architecture implements the Geiger avalanche quenching, bias, reset, and time to digital conversion (TDC) functions in full-digital design, and uses time domain over-sampling (vernier) to allow high temporal resolution at low clock rates, increased data yield, and improved utilization of the laser beam.

  1. Non-Destructive Evaluation (NDE) Technology Initiatives. Delivery Order 0031: Modeling of Eddy Current Array Sensor Sensitivities

    DTIC Science & Technology

    2002-10-01

    numerical formulation was not com- pleted until August which left little time for coding. However, Vipul Katyal has work hard on the prototype of the new...sensor array for magnetic field measurement J. R. Bowler and V. Katyal Iowa State University, Center Nondestructive Evaluation, ASC II, 1915 Scholl

  2. Genome-wide association studies of agronomic and quality traits in a set of German winter barley (Hordeum vulgare L.) cultivars using Diversity Arrays Technology (DArT).

    PubMed

    Lex, Jeannette; Ahlemeyer, Jutta; Friedt, Wolfgang; Ordon, Frank

    2014-08-01

    A set of about 100 winter barley (Hordeum vulgare L.) cultivars, comprising diverse and economically important German barley elite germplasm released during the last six decades, was previously genotypically characterized by single nucleotide polymorphism (SNP) markers using the Illumina GoldenGate BeadArray Technology to detect associations with phenotypic data estimated in three-year field trials at 12 locations. In order to identify further associations and to obtain information on whether the marker type influences the outcome of association genetics studies, the set of winter barley cultivars was re-analyzed using Diversity Arrays Technology (DArT) markers. As with the analysis of the SNPs, only polymorphic markers present at an allele frequency >5% were included to detect associations in a mixed linear model (MLM) approach using the TASSEL software (P ≤ 0.001). The population structure and kinship matrix were estimated on 72 simple sequence repeats (SSRs) covering the whole barley genome. The respective average linkage disequilibrium (LD) analyzed with DArT markers was estimated at 5.73 cM. A total of 52 markers gave significant associations with at least one of the traits estimated which, therefore, may be suitable for marker-assisted breeding. In addition, by comparing the results to those generated using the Illumina GoldenGate BeadArray Technology, it turned out that a different number of associations for respective traits is detected, depending on the marker system. However, as only a few of the respective DArT and Illumina markers are present in a common map, no comprehensive comparison of the detected associations was feasible, but some were probably detected in the same chromosomal regions. Because of the identification of additional marker-trait associations, it may be recommended to use both marker techniques in genome-wide association studies.

  3. 76 FR 6839 - ActiveCore Technologies, Inc., Battery Technologies, Inc., China Media1 Corp., Dura Products...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-08

    ... From the Federal Register Online via the Government Publishing Office SECURITIES AND EXCHANGE COMMISSION ActiveCore Technologies, Inc., Battery Technologies, Inc., China Media1 Corp., Dura Products... concerning the securities of Battery Technologies, Inc. because it has not filed any periodic reports...

  4. HEB heterodyne focal plane arrays: a terahertz technology for high sensitivity near-range security imaging systems

    NASA Astrophysics Data System (ADS)

    Gerecht, Eyal; Gu, Dazhen; Yngvesson, Sigfrid; Rodriguez-Morales, Fernando; Zannoni, R.; Nicholson, John

    2005-05-01

    We have achieved the first demonstration of a low-noise heterodyne array operating at a frequency above 1 THz (1.6 THz). The prototype array has three elements, consisting of NbN hot electron bolometer (HEB) detectors on silicon substrates. We use a quasi-optical design to couple the signal and local oscillator (LO) power to the detector. We also demonstrate, for the first time, how the HEB detectors can be intimately integrated in the same block with monolithic microwave integrated circuit (MMIC) IF amplifiers. Such focal plane arrays can be increased in size to a few hundred elements using the next generation fabrication architecture for compact and easy assembly. Future HEB-based focal plane arrays will make low-noise heterodyne imaging systems with high angular resolution possible from 500 GHz to several terahertz. Large low-noise HEB arrays are well suited for real-time video imaging at any frequency over the entire terahertz spectrum. This is made possible by virtue of the extremely low local oscillator power requirements of the HEB detectors (a few hundred nanowatts to a microwatt per pixel). The operating temperature is 4 to 6 K, which can be provided by a compact and mobile cryocooler system, developed as a spin-off from the space program. The terahertz HEB imager consists of a computer-controlled optical system mounted on an elevation and azimuth scanning translator which provides a two-dimensional image of the target. We present preliminary measured data at the symposium for a terahertz security system of this type.

  5. L-Band Ionosphere Scintillations Observed by A Spaced GPS Receiver Array during Recent Active Experiments at HAARP

    NASA Astrophysics Data System (ADS)

    Morton, Y.; Pelgrum, W.; van Graas, F.; Gunawardena, S.; Charney, D.; Peng, S.; Triplett, J.; Vikram, P.; Vemuru, A.

    2010-12-01

    L-Band Ionosphere Scintillations Observed by A Spaced GPS Receiver Array during Recent Active Experiments at HAARP Jade Morton*, Wouter Pelgrum**, Sanjeev Gunawardena**, Frank van Graas**, Dan Charney*, Senlin Peng***, Jeff Triplett*, Ajay Vemuru** * Department of Electrical and Computer Engineering, Miami University ** Avionics Engineering Center, Ohio University *** Department of Electrical and Computer Engineering, Virginia Tech Ionosphere irregularities can cause scintillation of satellite-based radio communication, navigation, and surveillance signals. While these scintillation effects will impact the corresponding receiver and system performance, carefully recovered signal parameters serve as a means of studying the background state and dynamics of the ionosphere. In this presentation, we will describe our recent effort in establishing a unique spaced GNSS receiver array at HAARP, Alaska to collect GPS and GLONASS satellite signals at various stages of the GNSS receiver processing. Preliminary receiver processing results as well as additional on-site diagnostic instrumentation measurements obtained from two active heating experiment campaigns will be presented to demonstrate the feasibility and effectiveness of our experimental data collection system in providing insightful details of ionosphere responses to active perturbations.

  6. Promoting Physical Activity through Hand-Held Computer Technology

    PubMed Central

    King, Abby C.; Ahn, David K.; Oliveira, Brian M.; Atienza, Audie A.; Castro, Cynthia M.; Gardner, Christopher D.

    2009-01-01

    Background Efforts to achieve population-wide increases in walking and similar moderate-intensity physical activities potentially can be enhanced through relevant applications of state-of-the-art interactive communication technologies. Yet few systematic efforts to evaluate the efficacy of hand-held computers and similar devices for enhancing physical activity levels have occurred. The purpose of this first-generation study was to evaluate the efficacy of a hand-held computer (i.e., personal digital assistant [PDA]) for increasing moderate intensity or more vigorous (MOD+) physical activity levels over 8 weeks in mid-life and older adults relative to a standard information control arm. Design Randomized, controlled 8-week experiment. Data were collected in 2005 and analyzed in 2006-2007. Setting/Participants Community-based study of 37 healthy, initially underactive adults aged 50 years and older who were randomized and completed the 8-week study (intervention=19, control=18). Intervention Participants received an instructional session and a PDA programmed to monitor their physical activity levels twice per day and provide daily and weekly individualized feedback, goal setting, and support. Controls received standard, age-appropriate written physical activity educational materials. Main Outcome Measure Physical activity was assessed via the Community Healthy Activities Model Program for Seniors (CHAMPS) questionnaire at baseline and 8 weeks. Results Relative to controls, intervention participants reported significantly greater 8-week mean estimated caloric expenditure levels and minutes per week in MOD+ activity (p<0.04). Satisfaction with the PDA was reasonably high in this largely PDA-naive sample. Conclusions Results from this first-generation study indicate that hand-held computers may be effective tools for increasing initial physical activity levels among underactive adults. PMID:18201644

  7. Aerospace university activity for the development of information and telecommunication and space technologies using the mechanisms of technological platforms

    NASA Astrophysics Data System (ADS)

    Kovalev, I. V.; Loginov, Y. Y.; Zelenkov, P. V.

    2015-01-01

    The relevance and perspective of the technological platform "Information and telecommunication and space technology for innovative development of Siberia" with the active participation of the Siberian State Aerospace University are discussed. The technology platform is a form of implementing public-private partnership, a way of mobilizing capacity of stakeholders (government, business, scientific community) and tool for creating science, technology and innovation policy to maintain the innovative development and technological modernization of the economy as part of the development of information and telecommunication and space technology.

  8. Effect of the composition of Ti alloy on the photocatalytic activities of Ti-based oxide nanotube arrays prepared by anodic oxidation

    NASA Astrophysics Data System (ADS)

    Tang, Dingding; Wang, Yixin; Zhao, Yuwei; Yang, Yijia; Zhang, Lieyu; Mao, Xuhui

    2014-11-01

    Three types of Ti-based oxide nanotube arrays are prepared by anodic oxidation of pure Ti and Ti alloys (Ti-0.2Pd and Ti-6Al-4V) in the glycol-2 wt% H2O-0.3 wt% NH4F solution. The nanotube arrays are characterized by a series of techniques, including SEM, TEM, EIS, XRD, EDS, ICP, XPS and UV-vis DRS, to elucidate the effect of alloying elements on the properties of titania nanotube arrays. The results suggest that aluminium and vanadium elements greatly slow down the growth rate and therefore decrease the yield of nanotube arrays. Al and V deteriorate the photoreactivity of the resultant nanotube arrays. The palladium inside the Ti-0.2Pd alloy-derived nanotube arrays cannot be detected by EDS or XPS, but is quantitatively determined by ICP analysis. Incorporation of Pd significantly improves the photocatalytic activity of the resultant titania nanotube arrays powder. The presence of Pd element not only enhances the light absorption, but also facilitates the separation of photogenerated charge carriers. The uniform doping of Pd into the microstructure endows nanotube arrays with resistance to sulphur poison and preferable stability for organic degradation. This study suggests that anodization of Ti alloys, rather than pure Ti metal, allows to produce micron-sized high-performance photocatalysts for environmental and energy applications.

  9. Present status of some technological activities supporting the MOLCARE project

    SciTech Connect

    Torazza, A.; Rocchini, G.; Scagliotti, M.

    1996-12-31

    The development of MCFC stack technology is carried out at Ansaldo Ricerche in the framework of the MOLCARE project, a cooperation with Spanish companies under a partial UE funding, while a specific research program concerning the physico-chemical characterization of materials is performed jointly by CISE and ENEL. The project includes the development, the construction and the testing of a full scale 100 kW prototype, the assessment of stack technology on subscale stacks, the mathematical modelling of the MCFC based plants and the basic researches. The aim of the basic researches, carried out on single cells, is to improve the effectiveness and durability of both the active and the hardware materials. The Ansaldo stack technology is based on external manifolding. The full scale 100 kW prototype will be integrated with the sensible heat reformer and other ancillary equipments according to the {open_quote}Compact Unit (CU){close_quotes} concept. These technical choices stress requirements for manifold gasket configuration. electrolyte migration control, {Delta}p management and porous component compaction.

  10. The CHARA optical array

    NASA Astrophysics Data System (ADS)

    McAlister, Harold A.

    1992-11-01

    The Center for High Angular Resolution Astronomy (CHARA) was established in the College of Arts and Sciences at Georgia State University in 1984 with the goals of designing, constructing, and then operating a facility for very high spatial resolution astronomy. The interest in such a facility grew out of the participants' decade of activity in speckle interferometry. Although speckle interferometry continues to provide important astrophysical measurements of a variety of objects, many pressing problems require resolution far beyond that which can be expected from single aperture telescopes. In early 1986, CHARA received a grant from the National Science Foundation which has permitted a detailed exploration of the feasibility of constructing a facility which will provide a hundred-fold increase in angular resolution over what is possible by speckle interferometry at the largest existing telescopes. The design concept for the CHARA Array was developed initially with the contractural collaboration of United Technologies Optical Systems, Inc., in West Palm Beach, Florida, an arrangement that expired in August 1987. In late November 1987, the Georgia Tech Research Institute joined with CHARA to continue and complete the design concept study. Very high-resolution imaging at optical wavelengths is clearly coming of age in astronomy. The CHARA Array and other related projects will be important and necessary milestones along the way toward the development of a major national facility for high-resolution imaging--a true optical counterpart to the Very Large Array. Ground-based arrays and their scientific output will lead to high resolution facilities in space and, ultimately, on the Moon.

  11. AlGaInN laser diode bar and array technology for high power and individually addressable applications

    NASA Astrophysics Data System (ADS)

    Najda, Stephen P.; Perlin, Piotr; Suski, Tadek; Marona, Lucja; Boćkowski, Mike; Leszczyński, Mike; Wisniewski, Przemek; Czernecki, Robert; Kucharski, Robert; Targowski, Grzegorz

    2015-05-01

    The AlGaInN material system allows for laser diodes to be fabricated over a very wide range of wavelengths from u.v., ~380nm, to the visible ~530nm, by tuning the indium content of the laser GaInN quantum well. Low defectivity and high uniformity GaN substrates allows arrays and bars of AlGaInN lasers with up to 20 emitters to be fabricated to obtain optical powers up to 4W at 395nm. AlGaInN laser bars are suitable for optical pumps and novel extended cavity systems for a wide range of applications. An alternative package configuration for AlGaInN laser arrays allows for each individual laser to be addressed individually allowing complex free-space and/or fibre optic system integration with a very small form-factor.

  12. Study of LWIR and VLWIR Focal Plane Array Developments: Comparison Between p-on- n and Different n-on- p Technologies on LPE HgCdTe

    NASA Astrophysics Data System (ADS)

    Gravrand, O.; Mollard, L.; Largeron, C.; Baier, N.; Deborniol, E.; Chorier, Ph.

    2009-08-01

    The very long infrared wavelength (>14 μm) is a very challenging range for the design of mercury cadmium telluride (HgCdTe) large focal plane arrays (FPAs). The need (mainly expressed by the space industry) for very long wave FPAs appears very difficult to fulfil. High homogeneity, low defect rate, high quantum efficiency, low dark current, and low excess noise are required. Indeed, for such wavelength, the corresponding HgCdTe gap becomes smaller than 100 meV and each step from the metallurgy to the technology becomes critical. This paper aims at presenting a status of long and very long wave FPAs developments at DEFIR (LETI-LIR/Sofradir joint venture). This study will focus on results obtained in our laboratory for three different ion implanted technologies: n-on- p mercury vacancies doped technology, n-on- p extrinsic doped technology, and p-on- n arsenic on indium technology. Special focus is given to 15 μm cutoff n/ p FPA fabricated in our laboratory demonstrating high uniformity, diffusion and shot noise limited photodiodes at 50 K.

  13. Fe(3+)-Doped TiO₂ Nanotube Arrays on Ti-Fe Alloys for Enhanced Photoelectrocatalytic Activity.

    PubMed

    Yu, Jiangdong; Wu, Zhi; Gong, Cheng; Xiao, Wang; Sun, Lan; Lin, Changjian

    2016-06-06

    Highly ordered, vertically oriented Fe(3+)-doped TiO₂ nanotube arrays (Fe-TNTs) were prepared on Ti-Fe alloy substrates with different Fe contents by the electrochemical anodization method. The as-prepared Fe-TNTs were characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and related electrochemical techniques. XPS results demonstrated that Fe(3+) ions were successfully doped into TiO₂ nanotubes. The photoelectrochemical activity of Fe-TNTs was compared with that of pure TiO₂ nanotube arrays (TNTs). The results showed that Fe-TNTs grown on low concentration (0.5 wt %-1 wt % Fe) Ti-Fe alloys possessed higher photocurrent density than TNTs. The Fe-TNTs grown on Ti-Fe alloy containing 0.8 wt % Fe exhibited the highest photoelectrochemical activity and the photoelectrocatalytic degradation rate of methylene blue (MB) aqueous solution was significantly higher than that of TNTs.

  14. Fe3+-Doped TiO2 Nanotube Arrays on Ti-Fe Alloys for Enhanced Photoelectrocatalytic Activity

    PubMed Central

    Yu, Jiangdong; Wu, Zhi; Gong, Cheng; Xiao, Wang; Sun, Lan; Lin, Changjian

    2016-01-01

    Highly ordered, vertically oriented Fe3+-doped TiO2 nanotube arrays (Fe-TNTs) were prepared on Ti-Fe alloy substrates with different Fe contents by the electrochemical anodization method. The as-prepared Fe-TNTs were characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and related electrochemical techniques. XPS results demonstrated that Fe3+ ions were successfully doped into TiO2 nanotubes. The photoelectrochemical activity of Fe-TNTs was compared with that of pure TiO2 nanotube arrays (TNTs). The results showed that Fe-TNTs grown on low concentration (0.5 wt %–1 wt % Fe) Ti-Fe alloys possessed higher photocurrent density than TNTs. The Fe-TNTs grown on Ti-Fe alloy containing 0.8 wt % Fe exhibited the highest photoelectrochemical activity and the photoelectrocatalytic degradation rate of methylene blue (MB) aqueous solution was significantly higher than that of TNTs. PMID:28335234

  15. Photocatalytic Activity and Photocurrent Properties of TiO2 Nanotube Arrays Influenced by Calcination Temperature and Tube Length

    NASA Astrophysics Data System (ADS)

    Hou, Jian; Zhang, Min; Yan, Guotian; Yang, Jianjun

    2012-06-01

    In this article, titanium oxide nanotube arrays (TiO2-NTAs) were fabricated by anodic oxidation in an ethylene glycol (EG) electrolyte solution containing 0.25 wt.% NH4F. By varying anodized time and annealed temperature, the obtained nanotube arrays behaved different photocatalytic (PC) activities and photocurrent properties. These samples were characterized by scanning electronic microscope (SEM), X-ray powder diffraction (XRD). It was indicated in SEM images that TiO2 nanotube manifests highly ordered structure which, however, has been completely destroyed when the temperature comes to 800°C. XRD manifested that TiO2 nanotubes with various kinds of length all possessed anatase crystallite when annealed at 500°C; meanwhile, with certain length, TiO2-NTAs annealed at series calcination temperature range of 300-600°C also presented anatase crystallite, which is gradually enhanced with the increment of temperature. At 700°C, mixed structure was observed which was made up of proportions of overwhelming anatase and toothful rutile. Methyl blue (MB) degradation and photocurrent measurement testified that TiO2-NTAs under 4 h oxidation and 3 h of 600°C calcination manifested the highest activity and photocurrent density.

  16. Screening, verification, and analysis of biomarkers for drug-induced cardiac toxicity in vitro based on RTCA coupled with PCR Array technology.

    PubMed

    Zhang, Lu; Xu, Meng-Xi; Yin, Qing-Sheng; Zhu, Cai-Ying; Cheng, Xue-Lian; Ren, Yi-Ran; Zhuang, Peng-Wei; Zhang, Yan-Jun

    2017-02-15

    Cardiotoxicity is one of the most serious side effects of new drugs. Early detection of the drug induced cardiotoxicity based on the biomarkers provides an important preventative strategy for detecting potential cardiotoxicity of candidate drugs. In this study, we aim to identify the predictive genomics biomarkers for drug-induced cardiac toxicity based on the RTCA coupled with PCR Array technology in primary cells. Three prototypical cardiotoxic compounds (doxorubicin, isoproterenol, ouabain) with different mechanisms were firstly real-time monitored to diagnose the cytotoxicity by using the RTCA, while the functional alterations of cardiomyocytes were also monitored by analyzing the beating frequency of cardiomyocytes. Then cardiac specific toxicity gene expression changes were studied by using the technology of PCR Array, which can detect the changes of 84 cardiac functions related genes. Rps6kb1 was identified to be the common cardiac biomarkers by using multivariate statistical and integration analyses. The biomarker was further verified by selecting other drugs with or without cardiotoxicity, and the results showed that the gene exhibited specific changes in cardiac toxicity. Moreover, IPA was applied to combine relevant pathways of Rps6kb1, and identify the main types of cardiac toxicity. These results would further enrich the evaluating strategy of drug-induced cardiotoxicity in vitro, and Rps6kb1 could be used as the specific biomarker of cardiotoxcity during safety assessment of the novel drug candidates.

  17. Insider Threat Study: Illicit Cyber Activity in the Information Technology and Telecommunications Sector

    DTIC Science & Technology

    2008-01-01

    Insider Threat Study: Illicit Cyber Activity in the Information Technology and Telecommunications Sector Eileen Kowalski...TITLE AND SUBTITLE Insider Threat Study: Illicit Cyber Activity in the Information Technology and Telecommunications Sector 5a. CONTRACT NUMBER 5b...Insider Threat Study: Illicit Cyber Activity in the Information Technology and Telecommunications Sector Page 2 TABLE OF CONTENTS SECTION 1

  18. Thermo-Magneto-Electric Generator Arrays for Active Heat Recovery System

    PubMed Central

    Chun, Jinsung; Song, Hyun-Cheol; Kang, Min-Gyu; Kang, Han Byul; Kishore, Ravi Anant; Priya, Shashank

    2017-01-01

    Continued emphasis on development of thermal cooling systems is being placed that can cycle low grade heat. Examples include solar powered unmanned aerial vehicles (UAVs) and data storage servers. The power efficiency of solar module degrades at elevated temperature, thereby, necessitating the need for heat extraction system. Similarly, data centres in wireless computing system are facing increasing efficiency challenges due to high power consumption associated with managing the waste heat. We provide breakthrough in addressing these problems by developing thermo-magneto-electric generator (TMEG) arrays, composed of soft magnet and piezoelectric polyvinylidene difluoride (PVDF) cantilever. TMEG can serve dual role of extracting the waste heat and converting it into useable electricity. Near room temperature second-order magnetic phase transition in soft magnetic material, gadolinium, was employed to obtain mechanical vibrations on the PVDF cantilever under small thermal gradient. TMEGs were shown to achieve high vibration frequency at small temperature gradients, thereby, demonstrating effective heat transfer. PMID:28145516

  19. Simultaneous Solar Maximum Mission (SMM) and very large array observations of solar active regions

    NASA Technical Reports Server (NTRS)

    Lang, K. R.

    1986-01-01

    The research deals mainly with Very Large Array and Solar Maximum Mission observations of the ubiquitous coronal loops that dominate the structure of the low corona. As illustrated, the observations of thermal cyclotron lines at microwave wavelengths provide a powerful new method of accurately specifying the coronal magnetic field strength. Processes are delineated that trigger solar eruptions from coronal loops, including preburst heating and the magnetic interaction of coronal loops. Evidence for coherent burst mechanisms is provided for both the Sun and nearby stars, while other observations suggest the presence of currents that may amplify the coronal magnetic field to unexpectedly high levels. The existence is reported of a new class of compact, variable moving sources in regions of apparently weak photospheric field.

  20. Thermo-Magneto-Electric Generator Arrays for Active Heat Recovery System.

    PubMed

    Chun, Jinsung; Song, Hyun-Cheol; Kang, Min-Gyu; Kang, Han Byul; Kishore, Ravi Anant; Priya, Shashank

    2017-02-01

    Continued emphasis on development of thermal cooling systems is being placed that can cycle low grade heat. Examples include solar powered unmanned aerial vehicles (UAVs) and data storage servers. The power efficiency of solar module degrades at elevated temperature, thereby, necessitating the need for heat extraction system. Similarly, data centres in wireless computing system are facing increasing efficiency challenges due to high power consumption associated with managing the waste heat. We provide breakthrough in addressing these problems by developing thermo-magneto-electric generator (TMEG) arrays, composed of soft magnet and piezoelectric polyvinylidene difluoride (PVDF) cantilever. TMEG can serve dual role of extracting the waste heat and converting it into useable electricity. Near room temperature second-order magnetic phase transition in soft magnetic material, gadolinium, was employed to obtain mechanical vibrations on the PVDF cantilever under small thermal gradient. TMEGs were shown to achieve high vibration frequency at small temperature gradients, thereby, demonstrating effective heat transfer.

  1. A Phased-Array Stimulator System for Studying Planar and Curved Cardiac Activation Wave Fronts

    PubMed Central

    Abbas, Rashida A.; Lin, Shien Fong; Mashburn, David; Xu, Junkai; Wikswo, John P.

    2009-01-01

    Wave front propagation in cardiac tissue is affected greatly by the geometry of the wave front. We describe a computer-controlled stimulator system that creates reproducible wave fronts of a predetermined shape and orientation for the investigation of the effects of wave front geometry. We conducted demonstration experiments on isolated perfused rabbit hearts, which were stained with the voltage-sensitive dye, di-4-ANEPPS. The wave fronts were imaged using a laser and a CCD camera. The stimulator and imaging systems have been used to characterize the relationship between wave front velocity and fiber orientation. This approach has potential applications in investigating curvature effects, testing numerical models of cardiac tissue, and creating complex wave fronts using one-, twoor three-dimensional electrode arrays. PMID:18232365

  2. Thermo-Magneto-Electric Generator Arrays for Active Heat Recovery System

    NASA Astrophysics Data System (ADS)

    Chun, Jinsung; Song, Hyun-Cheol; Kang, Min-Gyu; Kang, Han Byul; Kishore, Ravi Anant; Priya, Shashank

    2017-02-01

    Continued emphasis on development of thermal cooling systems is being placed that can cycle low grade heat. Examples include solar powered unmanned aerial vehicles (UAVs) and data storage servers. The power efficiency of solar module degrades at elevated temperature, thereby, necessitating the need for heat extraction system. Similarly, data centres in wireless computing system are facing increasing efficiency challenges due to high power consumption associated with managing the waste heat. We provide breakthrough in addressing these problems by developing thermo-magneto-electric generator (TMEG) arrays, composed of soft magnet and piezoelectric polyvinylidene difluoride (PVDF) cantilever. TMEG can serve dual role of extracting the waste heat and converting it into useable electricity. Near room temperature second-order magnetic phase transition in soft magnetic material, gadolinium, was employed to obtain mechanical vibrations on the PVDF cantilever under small thermal gradient. TMEGs were shown to achieve high vibration frequency at small temperature gradients, thereby, demonstrating effective heat transfer.

  3. Sensing technologies to measure metabolic activities in soil and assess its health conditions

    NASA Astrophysics Data System (ADS)

    De Cesare, Fabrizio; Macagnano, Antonella

    2013-04-01

    (olfactory fingerprint) typical of the analysed air sample. Due to these features, we decided to apply such a sensing technology to the analyses of soil atmospheres, because several processes in soil, both abiotic and biotic, result in gas and/or volatile production and the dynamics of such releases may also be affected by several additional environmental factors, such as soil moisture, temperature, gas exchange rates with outer atmosphere, adsorption/desorption processes, etc. Then, the analysis of soil atmosphere may provide information about global soil conditions (e.g. soil quality and health), according to a holistic approach, where several factors are contemporarily taken into account. At the same time, the use of such a technology, if adequately trained on purpose, can supply information about a single or a pool of processes sharing similar features, which occur in soil over a certain period of time and mostly affecting soil atmosphere. According to these premises and hypotheses, we demonstrated that EN is an useful technology to measure soil microbial activity, through its correlation to specific metabolic activities occurring in soil (i.e. global and specific respiration and some enzyme activities), but also soil microbial biomass. On the basis of such evidences, we also were able to use this technology to assess the quality and health conditions of soil ecosystems in terms of metabolic indices previously identified, according to some metabolic parameters and biomass quantification of microbial populations. In other studies, we also applied EN technology, despite using a different set of sensors in the array, to analyse the atmosphere of soil ecosystems in order to assess their environmental conditions after contamination with polycyclic aromatic hydrocarbons (PAHs) (i.e. semivolatile - SVOCs - organic pollutants). In this case, EN technology resulted capable of distinguishing between contaminated and uncontaminated soils, according to the differences in a list of

  4. Tapping Technology's Potential: Shrinking Budgets, Looming Standards, and a Dizzying Array of Innovations Are Changing the Professional Learning Landscape

    ERIC Educational Resources Information Center

    Killion, Joellen

    2013-01-01

    As the call for professional learning that incorporates ongoing feedback and support increases and resources to address that need decline, more states, districts, schools, and individuals are turning to technology. Technology creates significant opportunities for more focused professional learning, especially when it is effectively integrated into…

  5. Magnetic arrays

    SciTech Connect

    Trumper, David L.; Kim, Won-jong; Williams, Mark E.

    1997-05-20

    Electromagnet arrays which can provide selected field patterns in either two or three dimensions, and in particular, which can provide single-sided field patterns in two or three dimensions. These features are achieved by providing arrays which have current densities that vary in the windings both parallel to the array and in the direction of array thickness.

  6. Magnetic arrays

    DOEpatents

    Trumper, D.L.; Kim, W.; Williams, M.E.

    1997-05-20

    Electromagnet arrays are disclosed which can provide selected field patterns in either two or three dimensions, and in particular, which can provide single-sided field patterns in two or three dimensions. These features are achieved by providing arrays which have current densities that vary in the windings both parallel to the array and in the direction of array thickness. 12 figs.

  7. Metabolic Enzyme Microarray Coupled with Miniaturized Cell-Culture Array Technology for High-Throughput Toxicity Screening

    PubMed Central

    Lee, Moo-Yeal; Dordick, Jonathan S.; Clark, Douglas S.

    2017-01-01

    Due to poor drug candidate safety profiles that are often identified late in the drug development process, the clinical progression of new chemical entities to pharmaceuticals remains hindered, thus resulting in the high cost of drug discovery. To accelerate the identification of safer drug candidates and improve the clinical progression of drug candidates to pharmaceuticals, it is important to develop high-throughput tools that can provide early-stage predictive toxicology data. In particular, in vitro cell-based systems that can accurately mimic the human in vivo response and predict the impact of drug candidates on human toxicology are needed to accelerate the assessment of drug candidate toxicity and human metabolism earlier in the drug development process. The in vitro techniques that provide a high degree of human toxicity prediction will be perhaps more important in cosmetic and chemical industries in Europe, as animal toxicity testing is being phased out entirely in the immediate future. We have developed a metabolic enzyme microarray (the Metabolizing Enzyme Toxicology Assay Chip, or MetaChip) and a miniaturized three-dimensional (3D) cell-culture array (the Data Analysis Toxicology Assay Chip, or DataChip) for high-throughput toxicity screening of target compounds and their metabolic enzyme-generated products. The human or rat MetaChip contains an array of encapsulated metabolic enzymes that is designed to emulate the metabolic reactions in the human or rat liver. The human or rat DataChip contains an array of 3D human or rat cells encapsulated in alginate gels for cell-based toxicity screening. By combining the DataChip with the complementary MetaChip, in vitro toxicity results are obtained that correlate well with in vivo rat data. PMID:20217581

  8. Impact of dewatering technologies on specific methanogenic activity.

    PubMed

    Batstone, Damien J; Lu, Yang; Jensen, Paul D

    2015-10-01

    Dewatering methods for recuperative thickening and final dewatering can potentially impact methanogenic activity and microbial community. This influences both the feasibility of recuperative thickening to increase solids residence time within a digester, and the utilisation of dewatered digestate as inoculum for new digesters. Thickening technology can reduce methanogenic activity through either air contact (rotary drum, DAF, or belt filter press), or by lysing cells through shear (centrifuge). To assess this, two plants with recuperative thickening (rotary drum) in their anaerobic digester, and five without recuperative thickening, had specific methanogenic activity tested in all related streams, including dewatering feed, thickened return, final cake, and centrate. All plants had high speed centrifuges for final dewatering. The digester microbial community was also assessed through 16s pyrotag sequencing and subsequent principal component analysis (PCA). The specific methanogenic activity of all samples was in the expected range of 0.2-0.4 gCOD gVS(-1)d(-1). Plants with recuperative thickening did not have lower digester activity. Centrifuge based dewatering had a significant and variable impact on methanogenic activity in all samples, ranging between 20% and 90% decrease but averaging 54%. Rotary drum based recuperative thickening had a far smaller impact on activity, with a 0% per-pass drop in activity in one plant, and a 20% drop in another. However, the presence of recuperative thickening was a major predictor of overall microbial community (PC1, p = 0.0024). Microbial community PC3 (mainly driven by a shift in methanogens) was a strong predictor for sensitivity in activity to shear (p = 0.0005, p = 0.00001 without outlier). The one outlier was related to a plant producing the wettest cake (17% solids). This indicates that high solids is a potential driver of sensitivity to shear, but that a resilient microbial community can also bestow resilience

  9. Performance of active vibration control technology: the ACTEX flight experiments

    NASA Astrophysics Data System (ADS)

    Nye, T. W.; Manning, R. A.; Qassim, K.

    1999-12-01

    This paper discusses the development and results of two intelligent structures space-flight experiments, each of which could affect architecture designs of future spacecraft. The first, the advanced controls technology experiment I (ACTEX I), is a variable stiffness tripod structure riding as a secondary payload on a classified spacecraft. It has been operating well past its expected life since becoming operational in 1996. Over 60 on-orbit experiments have been run on the ACTEX I flight experiment. These experiments form the basis for in-space controller design problems and for concluding lifetime/reliability data on the active control components. Transfer functions taken during the life of ACTEX I have shown consistent predictability and stability in structural behavior, including consistency with those measurements taken on the ground prior to a three year storage period and the launch event. ACTEX I can change its modal characteristics by employing its dynamic change mechanism that varies preloads in portions of its structure. Active control experiments have demonstrated maximum vibration reductions of 29 dB and 16 dB in the first two variable modes of the system, while operating over a remarkable on-orbit temperature range of -80 °C to 129 °C. The second experiment, ACTEX II, was successfully designed, ground-tested, and integrated on an experimental Department of Defense satellite prior to its loss during a launch vehicle failure in 1995. ACTEX II also had variable modal behavior by virtue of a two-axis gimbal and added challenges of structural flexibility by being a large deployable appendage. Although the loss of ACTEX II did not provide space environment experience, ground testing resulted in space qualifying the hardware and demonstrated 21 dB, 14 dB, and 8 dB reductions in amplitude of the first three primary structural modes. ACTEX II could use either active and/or passive techniques to affect vibration suppression. Both experiments trailblazed

  10. The Benchmark Active Controls Technology Model Aerodynamic Data

    NASA Technical Reports Server (NTRS)

    Scott, Robert C.; Hoadley, Sherwood T.; Wieseman, Carol D.; Durham, Michael H.

    1997-01-01

    The Benchmark Active Controls Technology (BACT) model is a part of the Benchmark Models Program (BMP). The BMP is a NASA Langley Research Center program that includes a series of models which were used to study different aeroelastic phenomena and to validate computational fluid dynamics codes. The primary objective of BACT testing was to obtain steady and unsteady loads, accelerations, and aerodynamic pressures due to control surface activity in order to calibrate unsteady CFD codes and active control design tools. Three wind-tunnel tests in the Transonic Dynamics Tunnel (TDT) have been completed. The first and parts of the second and third tests focused on collecting open-loop data to define the model's aeroservoelastic characteristics, including the flutter boundary across the Mach range. It is this data that is being presented in this paper. An extensive database of over 3000 data sets was obtained. This database includes steady and unsteady control surface effectiveness data, including pressure distributions, control surface hinge moments, and overall model loads due to deflections of a trailing edge control surface and upper and lower surface

  11. Actively Cooled SLMS(TM) Technology for HEL Applications

    NASA Technical Reports Server (NTRS)

    Jacoby, Marc T.; Goodman, William A.; Reily, Jack C.; Kegley, Jeffrey R.; Haight, Harlan J.; Tucker, John; Wright, Ernest R.; Hogue, William D.

    2005-01-01

    Mr. Jacoby is the Chief Scientist for Schafer's Lightweight Optical Systems business area with twenty four years experience in laser and optical systems for space and military applications. He and colleague Dr. Goodman conceived and developed Silicon Lightweight Mirrors (SLMS(TM)) technologies for space applications from the extreme UV to FAR IR wavelengths. Schafer has demonstrated two different methods for actively cooling our Silicon Lightweight Mirrors (SLMS(TM)) technology. Direct internal cooling was accomplished by flowing liquid nitrogen through the continuous open cell core of the SLMS(TM) mirror. Indirect external cooling was accomplished by flowing liquid nitrogen through a CTE matched Cesic square-tube manifold that was bonded to the back of the mirror in the center. Testing was done in the small 4-foot thermal/vacuum chamber located at the NASA/MSFC X-Ray Calibration Facility. Seven thermal diodes were located over the front side of the 5 inch diameter mirror and one was placed on the outlet side of the Cesic manifold. Results indicate that the mirror reaches steady state at 82K in less than four minutes for both cooling methods. The maximum temperature difference of the eight diodes was less than 200 mK when the mirror was internally cooled and covered with MLI to insulate it from the large 300 K aluminum plate that was used to mount it.

  12. Using LiDAR technology in forestry activities.

    PubMed

    Akay, Abdullah Emin; Oğuz, Hakan; Karas, Ismail Rakip; Aruga, Kazuhiro

    2009-04-01

    Managing natural resources in wide-scale areas can be highly time and resource consuming task which requires significant amount of data collection in the field and reduction of the data in the office to provide the necessary information. High performance LiDAR remote sensing technology has recently become an effective tool for use in applications of natural resources. In the field of forestry, the LiDAR measurements of the forested areas can provide high-quality data on three-dimensional characterizations of forest structures. Besides, LiDAR data can be used to provide very high quality and accurate Digital Elevation Model (DEM) for the forested areas. This study presents the progress and opportunities of using LiDAR remote sensing technology in various forestry applications. The results indicate that LiDAR based forest structure data and high-resolution DEMs can be used in wide-scale forestry activities such as stand characterizations, forest inventory and management, fire behaviour modeling, and forest operations.

  13. Self-Supported PtAuP Alloy Nanotube Arrays with Enhanced Activity and Stability for Methanol Electro-Oxidation.

    PubMed

    Zhang, Lili; Ding, Liang-Xin; Chen, Hongbin; Li, Dongdong; Wang, Suqing; Wang, Haihui

    2017-02-21

    Inhibiting CO formation can more directly address the problem of CO poisoning during methanol electro-oxidation. In this study, 1D self-supported porous PtAuP alloy nanotube arrays (ANTAs) are synthesized via a facile electro-codeposition approach and present enhanced activity and improved resistance to CO poisoning through inhibiting CO formation (non-CO pathway) during the methanol oxidation reaction in acidic medium. This well-controlled Pt-/transition metal-/nonmetal ternary nanostructure exhibits a specific electroactivity twice as great as that of PtAu alloy nanotube arrays and Pt/C. At the same time, PtAuP ANTAs show a higher ratio of forward peak current density (If ) to backward peak current density (Ib ) (2.34) than PtAu ANTAs (1.27) and Pt/C (0.78). The prominent If /Ib value of PtAuP ANTAs indicates that most of the intermediate species are electro-oxidized to carbon dioxide in the forward scan, which highlights the high electroactivity for methanol electro-oxidation.

  14. Comparison of Exams for Active Learning Technologies vs. Traditional Lectures

    NASA Astrophysics Data System (ADS)

    Hornstra, Andrew; Djordjevic, Branislav; Dworzecka, Maria

    2017-01-01

    George Mason University has first semester (PHYS-160) and second semester (PHYS-260) physics course which consist of two sections. One is a traditional lecture style format (TRAD) and the other is a newer format which is a take on the ``flipped'' classroom. This newer style is referred to as Active Learning with Technologies (ALT). This course style has been in place for several years and has been studied before within George Mason University for final grade differences. These studies suggested that the ALT sections performed better, but grade weighting consistency, test time, and test content were not strictly controlled. The purpose of this study is to cross-examine the performance of students in these different class formats during Fall 2016 (PHYS-260) and Spring 2015 (PHYS-160) on very nearly identical exams over identical test times while controlling for almost every variable.

  15. Technologies for imaging neural activity in large volumes

    PubMed Central

    Ji, Na; Freeman, Jeremy; Smith, Spencer L.

    2017-01-01

    Neural circuitry has evolved to form distributed networks that act dynamically across large volumes. Collecting data from individual planes, conventional microscopy cannot sample circuitry across large volumes at the temporal resolution relevant to neural circuit function and behaviors. Here, we review emerging technologies for rapid volume imaging of neural circuitry. We focus on two critical challenges: the inertia of optical systems, which limits image speed, and aberrations, which restrict the image volume. Optical sampling time must be long enough to ensure high-fidelity measurements, but optimized sampling strategies and point spread function engineering can facilitate rapid volume imaging of neural activity within this constraint. We also discuss new computational strategies for the processing and analysis of volume imaging data of increasing size and complexity. Together, optical and computational advances are providing a broader view of neural circuit dynamics, and help elucidate how brain regions work in concert to support behavior. PMID:27571194

  16. AlGaInN laser diode bar and array technology for high-power and individual addressable applications

    NASA Astrophysics Data System (ADS)

    Najda, S. P.; Perlin, P.; Suski, T.; Marona, L.; Boćkowski, M.; Leszczyński, M.; Wisniewski, P.; Czernecki, R.; Kucharski, R.; Targowski, G.

    2016-04-01

    The AlGaInN material system allows for laser diodes to be fabricated over a very wide range of wavelengths from u.v., ~380nm, to the visible ~530nm, by tuning the indium content of the laser GaInN quantum well, giving rise to new and novel applications for medical, industrial, display and scientific purposes. Ridge waveguide laser diode structures are fabricated to achieve single mode operation with high optical powers of >100mW with high reliability. Low defectivity and highly uniform GaN substrates allow arrays and bars of nitride lasers to be fabricated. We demonstrate the operation of monolithic AlGaInN laser bars with up to 20 emitters giving optical powers up to 4W cw at ~395nm with a common contact configuration. These bars are suitable for optical pumps and novel extended cavity systems. An alternative package configuration for AlGaInN laser arrays allows for each individual laser to be individually addressable allowing complex free-space and/or fibre optic system integration within a very small form-factor.

  17. Detection of hormone active chemicals using genetically engineered yeast cells and microfluidic devices with interdigitated array electrodes.

    PubMed

    Ino, Kosuke; Kitagawa, Yusuke; Watanabe, Tsuyoshi; Shiku, Hitoshi; Koide, Masahiro; Itayama, Tomoaki; Yasukawa, Tomoyuki; Matsue, Tomokazu

    2009-10-01

    Endocrine disruptors that act like hormones in the endocrine system might have toxic effects. Therefore, it is important to develop a portable device that can detect hormone active chemicals in samples rapidly and easily. In this study, a microfluidic device was developed for the detection of hormone active chemicals using genetically engineered yeast cells. The yeast cells were used as biosensors since they were genetically engineered to respond to the presence of hormone active chemicals by synthesizing beta-galactosidase (beta-gal). For achieving further sensitivity, we incorporated interdigitated array (IDA) electrodes (width, 1.2 microm; gap, 0.8 microm) with 40 electrode fingers into the analytical chamber of the microfluidic device. The yeast cells precultured with a hormone active chemical, 17beta-estradiol (E2), were trapped from the main channel of the device to the analytical camber by electrophoresis. After trapping in the analytical chamber, we performed electrochemical detection of beta-gal induced in the yeast cells with the IDA electrodes. Actually, electrochemical detection was performed on p-aminophenol that was converted from p-aminophenyl-beta-D-galactopyranoside with beta-gal. The electrochemical signals from the yeast cells precultured with 17beta-estradiol were successfully detected with the device. Furthermore, the inhibitory effects of antagonists such as tamoxifen were also detected electrochemically by using the device. Thus, the present microfluidic device can be used for highly sensitive detection of hormone active chemicals.

  18. NASA'S information technology activities for the 90's

    NASA Technical Reports Server (NTRS)

    Holcomb, Lee; Erickson, Dan

    1991-01-01

    The Office of Aeronautics, Exploration and Technology (OAET) is completing an extensive assessment of its nearly five hundred million dollars of proposed space technology development work. The budget is divided into four segments which are as follows: (1) the base research and technology program; (2) the Civil Space Technology Initiative (CSTI); (3) the Exploration Technology Program (ETP); and (4) the High Performance Computing Initiative (HPCI). The programs are briefly discussed in the context of Astrotech 21.

  19. Control growth of single crystalline ZnO nanorod arrays and nanoflowers with enhanced photocatalytic activity

    NASA Astrophysics Data System (ADS)

    Feng, Jiu-Ju; Wang, Zhen-Zhen; Li, Yong-Fang; Chen, Jian-Rong; Wang, Ai-Jun

    2013-04-01

    Single crystalline vertical nanorod arrays and nanoflowers of ZnO have been grown in situ on cheap zinc foils under hydrothermal conditions, by means of hexamethylenetetramine and ethanolamine, respectively. Their morphologies and crystal structures are characterized by X-ray diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy. The nanorods and flowers of ZnO grew along the { 10bar{1}1} and { 0001} planes, respectively. Both types of ZnO display high photocatalytic ability toward the degradation of methylene orange under UV irradiation. The ZnO nanorods show better performance than that of the ZnO nanoflowers, and the { 10bar{1}1} facets of the ZnO nanorods have higher photoactivity than that of the { 000bar{1}} or { 10bar{1}0} crystal planes. This is because the weaker coordinated O atoms on the surface are more likely to be saturated by H atoms in aqueous solution, thereby releasing more free OH radicals.

  20. Canada s activities on space debris mitigation technologies

    NASA Astrophysics Data System (ADS)

    Nikanpour, D.

    The threat of space debris to space activities is exponentially rising. Canada, as a space-faring nation having significant investment in space and astronauts participating in space missions, has recognized the risks arising from it and has been active as a participant in understanding and mitigate the problem. Since 1992, Canada has been involved with the creation of a sub-committee on space debris under the government's Interdepartmental Committee on Space (ICS) to deal with the policy and international cooperation on space debris. On the research front, Canadian Space Agency (CSA) has been coordinating the related researches within Canada. This paper outlines the major Canadian research activities on space debris and mitigation technologies along with CSA's future plan on the subject. Canadian research activities on space debris are in 3 major areas: (1) Measurement and modeling of space debris: The work has been led by the CSA (Space Technologies) with participations from research institutes and universities. The experiments cover the analysis and computational modeling of the space debris flux at orbital altitudes of interest for space activities. (2) Space debris mitigation: The technology for mitigating space debris is of key research interest and measures have been taken in the design and launch of LEO earth observation spacecraft, such as RADARSAT. RADARSAT-1, launched in 1995 and still operating, was one of the first commercial spacecraft to consider the effect of orbital debris in its design. Not only was the spacecraft designed to withstand a possible impact on orbit, and not be a source of debris from latches and tie-down mechanisms, but the launch of RADARSAT-1 was also delayed by 25 seconds in a very tight launch window, to avoid a possible impact on orbit. The design for the follow-on RADARSAT-2 spacecraft includes features to protect its Synthetic Aperture Radar (SAR) antenna against possible impact damage due to space debris as well as include

  1. Using Scientific Detective Videos to Support the Design of Technology Learning Activities

    ERIC Educational Resources Information Center

    Yu, Kuang-Chao; Fan, Szu-Chun; Tsai, Fu-Hsing; Chu, Yih-hsien

    2013-01-01

    This article examines the effect of scientific detective video as a vehicle to support the design of technology activities by technology teachers. Ten graduate students, including current and future technology teachers, participated in a required technology graduate course that used scientific detective videos as a pedagogical tool to motivate…

  2. Designing of Phased Array Transducers for Industrial Applications

    NASA Astrophysics Data System (ADS)

    Dumas, Ph.; Poguet, J.; Fleury, G.

    2004-02-01

    By increasing inspection speed, and deflection capabilities of the transducers, Phased-array technology has proved its interest to face new ∂ NDT challenges, and is becoming more and more popular in the main industrial fields of activities. This paper describes the main effects of specifications on transducer performances, and explains how to defined them. The second part speaks about the manufacturing step, showing the influence of component choice on performances. Several Phased-array applications examples illustrating these considerations will be presented.

  3. Active control of microbubbles stream in multi-bifurcated flow by using 2D phased array ultrasound transducer.

    PubMed

    Koda, Ren; Koido, Jun; Hosaka, Naoto; Ito, Takumi; Onogi, Shinya; Mochizuki, Takashi; Masuda, Kohji; Ikeda, Seiichi; Arai, Fumihito

    2013-01-01

    We have previously reported our attempt to propel microbbles in flow by a primary Bjerknes force, which is a physical phenomenon where an acoustic wave pushes an obstacle along its direction of propagation. However, when ultrasound was emitted from surface of the body, controlling bubbles in against flow was needed. It is unpractical to use multiple transducers to produce the same number of focal points because single element transducer cannot produce more than two focal points. In this study, we introduced a complex artificial blood vessel according to a capillary model and a 2D array transducer to produce multiple focal points for active control of microbubbles in against flow. Furthermore, we investigated bubble control in viscous fluid. As the results, we confirmed clearly path selection of MBs in viscous fluid as well as in water.

  4. The MU radar with active phased array system. I - Antenna and power amplifiers. II - In-house equipment

    NASA Astrophysics Data System (ADS)

    Fukao, S.; Sato, T.; Tsuda, T.; Kato, S.; Wakasugi, K.

    1985-12-01

    The MU (middle and upper atmosphere) radar of Japan, a 46.5 MHz pulse-modulated monostatic Doppler radar with an active phased array system, is described. The system's nominal beam width is 3.6 deg, and the peak radiation power is 1 MW with maximum average power of 50 kW. The system is composed of 475 crossed three-subelement Yagi antennas and an equivalent number of solid state power amplifiers. Each Yagi antenna is driven by a transmitter-receiver module with peak output power of 2.4 kW. This configuration enables very fast and almost continuous beam steering that has not been realized by other mesosphere-stratosphere-troposphere radars. The system's antenna and power amplifiers are described, as is the in-house equipment related to transmission reception, on-line data processing, and system control.

  5. Effects of various hydrogenated treatments on formation and photocatalytic activity of black TiO2 nanowire arrays

    NASA Astrophysics Data System (ADS)

    Wang, Chih-Chieh; Chou, Po-Hsun

    2016-08-01

    The effects of hydrogen thermal and plasma treatment on the formation and photocatalytic activities of black TiO2 nanowire arrays were investigated and discussed. After either the hydrogen thermal or plasma treatment, the TiO2 nanowires remained. However, in contrast to the plasma treated nanowires, the diameter of the thermal treated TiO2 nanowires reduced more significantly, which was attributed to a thicker surface amorphous layer and more oxygen vacancies. A higher photoresponse in both UV and visible light regions and more hydroxide groups were also observed for the thermal treated nanowires. In addition, the black nanowires possessed greater carrier concentration, leading to a more efficient separation of electron-hole pairs. As a consequence, much enhanced photoelectrochemical water splitting and photocatalytic degradation of methylene blue were obtained.

  6. Agricultural Science and Technology Teachers' Perceptions of iPod and Mp3 Technology Integration into Curricular and Cocurricular Activities

    ERIC Educational Resources Information Center

    Murphrey, Theresa Pesl; Miller, Kimberly A.; Roberts, T. Grady

    2009-01-01

    The purpose of this study was to describe agricultural science and technology teachers' reaction to iPod and mp3 technology use and potential use in both curricular and cocurricular activities. A total of 112 unique respondents provided written responses to open-ended questions. Study findings reveal that agricultural science and technology…

  7. Teachers as Co-Designers of Technology-Rich Learning Activities for Early Literacy

    ERIC Educational Resources Information Center

    Cviko, Amina; McKenney, Susan; Voogt, Joke

    2015-01-01

    Although kindergarten teachers often struggle with implementing technology, they are rarely involved in co-designing technology-rich learning activities. This study involved teachers in the co-design of technology-rich learning activities and sought to explore implementation and pupil learning outcomes. A case-study method was used to investigate:…

  8. Multibeam Phased Array Antennas

    NASA Technical Reports Server (NTRS)

    Popovic, Zoya; Romisch, Stefania; Rondineau, Sebastien

    2004-01-01

    In this study, a new architecture for Ka-band multi-beam arrays was developed and demonstrated experimentally. The goal of the investigation was to demonstrate a new architecture that has the potential of reducing the cost as compared to standard expensive phased array technology. The goals of this specific part of the project, as stated in the yearly statement of work in the original proposal are: 1. Investigate bounds on performance of multi-beam lens arrays in terms of beamwidths, volume (size), isolation between beams, number of simultaneous beams, etc. 2. Design a small-scale array to demonstrate the principle. The array will be designed for operation around 3OGHz (Ka-band), with two 10-degree beamwidth beams. 3. Investigate most appropriate way to accomplish fine-tuning of the beam pointing within 5 degrees around the main beam pointing angle.

  9. Spatial analysis of slowly oscillating electric activity in the gut of mice using low impedance arrayed microelectrodes.

    PubMed

    Taniguchi, Mizuki; Kajioka, Shunichi; Shozib, Habibul B; Sawamura, Kenta; Nakayama, Shinsuke

    2013-01-01

    Smooth and elaborate gut motility is based on cellular cooperation, including smooth muscle, enteric neurons and special interstitial cells acting as pacemaker cells. Therefore, spatial characterization of electric activity in tissues containing these electric excitable cells is required for a precise understanding of gut motility. Furthermore, tools to evaluate spatial electric activity in a small area would be useful for the investigation of model animals. We thus employed a microelectrode array (MEA) system to simultaneously measure a set of 8×8 field potentials in a square area of ∼1 mm(2). The size of each recording electrode was 50×50 µm(2), however the surface area was increased by fixing platinum black particles. The impedance of microelectrode was sufficiently low to apply a high-pass filter of 0.1 Hz. Mapping of spectral power, and auto-correlation and cross-correlation parameters characterized the spatial properties of spontaneous electric activity in the ileum of wild-type (WT) and W/W(v) mice, the latter serving as a model of impaired network of pacemaking interstitial cells. Namely, electric activities measured varied in both size and cooperativity in W/W(v) mice, despite the small area. In the ileum of WT mice, procedures suppressing the excitability of smooth muscle and neurons altered the propagation of spontaneous electric activity, but had little change in the period of oscillations. In conclusion, MEA with low impedance electrodes enables to measure slowly oscillating electric activity, and is useful to evaluate both histological and functional changes in the spatio-temporal property of gut electric activity.

  10. A gene-centric analysis of activated partial thromboplastin time and activated protein C resistance using the HumanCVD focused genotyping array.

    PubMed

    Gaunt, Tom R; Lowe, Gordon D O; Lawlor, Debbie A; Casas, Juan-Pablo; Day, Ian N M

    2013-07-01

    Activated partial thromboplastin time (aPTT) is an important routine measure of intrinsic blood coagulation. Addition of activated protein C (APC) to the aPTT test to produce a ratio, provides one measure of APC resistance. The associations of some genetic mutations (eg, factor V Leiden) with these measures are established, but associations of other genetic variations remain to be established. The objective of this work was to test for association between genetic variants and blood coagulation using a high-density genotyping array. Genetic association with aPTT and APC resistance was analysed using a focused genotyping array that tests approximately 50 000 single-nucleotide polymorphisms (SNPs) in nearly 2000 cardiovascular candidate genes, including coagulation pathway genes. Analyses were conducted on 2544 European origin women from the British Women's Heart and Health Study. We confirm associations with aPTT at the coagulation factor XII (F12)/G protein-coupled receptor kinase 6 (GRK6) and kininogen 1 (KNG1)/histidine-rich glycoprotein (HRG) loci, and identify novel SNPs at the ABO locus and novel locus kallikrein B (KLKB1)/F11. In addition, we confirm association between APC resistance and factor V Leiden mutation, and identify novel SNP associations with APC resistance in the HRG and F5/solute carrier family 19 member 2 (SLC19A2) regions. In conclusion, variation at several genetic loci influences intrinsic blood coagulation as measured by both aPTT and APC resistance.

  11. Sociotechnical Cultural Activity: Expanding an Understanding of Emergent Technology Practices

    ERIC Educational Resources Information Center

    Degennaro, Donna

    2008-01-01

    This paper examines the evolving participation of instructors and learners in an after-school web page-design course intended to improve technology practices. Defined here as technology fluency, these practices emerge through a highly fluctuating dance among social interactions with others and with the technology. In this digital divide…

  12. Kokkos Array

    SciTech Connect

    Edwards Daniel Sunderland, Harold Carter

    2012-09-12

    The Kokkos Array library implements shared-memory array data structures and parallel task dispatch interfaces for data-parallel computational kernels that are performance-portable to multicore-CPU and manycore-accelerator (e.g., GPGPU) devices.

  13. Large-scale nanophotonic phased array.

    PubMed

    Sun, Jie; Timurdogan, Erman; Yaacobi, Ami; Hosseini, Ehsan Shah; Watts, Michael R

    2013-01-10

    Electromagnetic phased arrays at radio frequencies are well known and have enabled applications ranging from communications to radar, broadcasting and astronomy. The ability to generate arbitrary radiation patterns with large-scale phased arrays has long been pursued. Although it is extremely expensive and cumbersome to deploy large-scale radiofrequency phased arrays, optical phased arrays have a unique advantage in that the much shorter optical wavelength holds promise for large-scale integration. However, the short optical wavelength also imposes stringent requirements on fabrication. As a consequence, although optical phased arrays have been studied with various platforms and recently with chip-scale nanophotonics, all of the demonstrations so far are restricted to one-dimensional or small-scale two-dimensional arrays. Here we report the demonstration of a large-scale two-dimensional nanophotonic phased array (NPA), in which 64 × 64 (4,096) optical nanoantennas are densely integrated on a silicon chip within a footprint of 576 μm × 576 μm with all of the nanoantennas precisely balanced in power and aligned in phase to generate a designed, sophisticated radiation pattern in the far field. We also show that active phase tunability can be realized in the proposed NPA by demonstrating dynamic beam steering and shaping with an 8 × 8 array. This work demonstrates that a robust design, together with state-of-the-art complementary metal-oxide-semiconductor technology, allows large-scale NPAs to be implemented on compact and inexpensive nanophotonic chips. In turn, this enables arbitrary radiation pattern generation using NPAs and therefore extends the functionalities of phased arrays beyond conventional beam focusing and steering, opening up possibilities for large-scale deployment in applications such as communication, laser detection and ranging, three-dimensional holography and biomedical sciences, to name just a few.

  14. Greenhouse gas (GHG) mitigation technology performance: Activities of the GHG Technology Verification Center. Report for November 1997--September 1998

    SciTech Connect

    Piccot, S.D.; Kirchgessner, D.A.

    1998-12-31

    The paper describes the Greenhouse Gas (GHG) Technology Verification Center`s mission, operational characteristics, and current activities in the natural gas industry, solid waste landfill industry, energy industries, and microelectronics industry. It also outlines the Center`s future plans and gives results of a recent phosphoric acid fuel cell verification at two landflls in the US. It describes how technology vendors, developers, users, and others can utilize the Center`s testing, analysis, and outreach activities and outlines the types of technologies planned for testing over the next 3 to 5 years.

  15. Nanocylinder arrays

    DOEpatents

    Tuominen, Mark; Schotter, Joerg; Thurn-Albrecht, Thomas; Russell, Thomas P.

    2007-03-13

    Pathways to rapid and reliable fabrication of nanocylinder arrays are provided. Simple methods are described for the production of well-ordered arrays of nanopores, nanowires, and other materials. This is accomplished by orienting copolymer films and removing a component from the film to produce nanopores, that in turn, can be filled with materials to produce the arrays. The resulting arrays can be used to produce nanoscale media, devices, and systems.

  16. Nanocylinder arrays

    DOEpatents

    Tuominen, Mark; Schotter, Joerg; Thurn-Albrecht, Thomas; Russell, Thomas P.

    2009-08-11

    Pathways to rapid and reliable fabrication of nanocylinder arrays are provided. Simple methods are described for the production of well-ordered arrays of nanopores, nanowires, and other materials. This is accomplished by orienting copolymer films and removing a component from the film to produce nanopores, that in turn, can be filled with materials to produce the arrays. The resulting arrays can be used to produce nanoscale media, devices, and systems.

  17. Engineering and Technology Challenges for Active Debris Removal

    NASA Technical Reports Server (NTRS)

    Liou, Jer-Chyi

    2011-01-01

    After more than fifty years of space activities, the near-Earth environment is polluted with man-made orbital debris. The collision between Cosmos 2251 and the operational Iridium 33 in 2009 signaled a potential collision cascade effect, also known as the "Kessler Syndrome", in the environment. Various modelling studies have suggested that the commonly-adopted mitigation measures will not be sufficient to stabilize the future debris population. Active debris removal must be considered to remediate the environment. This paper summarizes the key issues associated with debris removal and describes the technology and engineering challenges to move forward. Fifty-four years after the launch of Sputnik 1, satellites have become an integral part of human society. Unfortunately, the ongoing space activities have left behind an undesirable byproduct orbital debris. This environment problem is threatening the current and future space activities. On average, two Shuttle window panels are replaced after every mission due to damage by micrometeoroid or orbital debris impacts. More than 100 collision avoidance maneuvers were conducted by satellite operators in 2010 to reduce the impact risks of their satellites with respect to objects in the U.S. Space Surveillance Network (SSN) catalog. Of the four known accident collisions between objects in the SSN catalog, the last one, collision between Cosmos 2251 and the operational Iridium 33 in 2009, was the most significant. It was the first ever accidental catastrophic destruction of an operational satellite by another satellite. It also signaled the potential collision cascade effect in the environment, commonly known as the "Kessler Syndrome," predicted by Kessler and Cour-Palais in 1978 [1]. Figure 1 shows the historical increase of objects in the SSN catalog. The majority of the catalog objects are 10 cm and larger. As of April 2011, the total objects tracked by the SSN sensors were more than 22,000. However, approximately 6000 of

  18. Active Dust Control and Mitigation Technology for Lunar and Martian Exploration

    NASA Technical Reports Server (NTRS)

    Calle, C. I.; Buhler, C. R.; Johansen, M. R.; Hogue, M. D.; Immer, C. D.; Ferreira, J.; Snyder, S. J.

    2010-01-01

    Mars is covered with a layer of dust that has been homogenized by global dust storms. Dust, levitated by these storms as well as by the frequent dust devils, is the dominant weather phenomenon on Mars. NASA's Mars exploration rovers have shown that atmospheric dust falling on solar panels can decrease their efficiency to the point of rendering the rover unusable. Dust covering the surface of the moon is expected to be electrostatically charged due to the solar wind, cosmic rays, and the solar radiation itself through the photoelectric effect. Electrostatically charged dust has a large tendency to adhere to surfaces. The Apollo missions to the moon showed that lunar dust adhesion can hinder manned and unmanned exploration activities. In this paper, we report on our efforts to develop and electrodynamic dust shield to prevent the accumulation of dust on surfaces and to remove dust already adhering to those surfaces. The technology uses electrostatic and dielectrophoretic forces to carry dust particles off surfaces and to generate an electrodynamic shield that prevents further accumulation of dust. The concept of the electrodynamic dust shield was introduced by NASA in the late 1960s and later reduced to practice during the 1970s for terrestrial applications. In 2003, our laboratory, in collaboration with several universities, applied this technology to space applications, specifically to remove dust from solar panels on Mars. We show how, with an appropriate design, we can prevent the electrostatic breakdown at the low Martian atmospheric pressures. We are also able to show that uncharged dust can be lifted and removed from surfaces under simulated Martian environmental conditions. We have also been able to develop a version of the electrodynamic dust shield working under hard vacuum conditions that simulate the lunar environment. We have implemented the electrodynamic dust shield on solar arrays, optical systems, spectrometers, viewports, thermal radiators

  19. Educational Technology as a Subversive Activity: Questioning Assumptions Related to Teaching and Leading with Technology

    ERIC Educational Resources Information Center

    Kruger-Ross, Matthew J.; Holcomb, Lori B.

    2012-01-01

    The use of educational technologies is grounded in the assumptions of teachers, learners, and administrators. Assumptions are choices that structure our understandings and help us make meaning. Current advances in Web 2.0 and social media technologies challenge our assumptions about teaching and learning. The intersection of technology and…

  20. Past, present, and future activities in space power technology in the United States of America

    NASA Technical Reports Server (NTRS)

    Ambrus, Judith H.

    1987-01-01

    Space power technology research in the U.S. is examined. The objectives for advanced power systems are long life, safety, flexibility, modularity, growth capability, and autonomy. Research in the areas of photovoltaic arrays, electrical energy storage, and the development of solar dynamic power systems and radio thermal generators is described. The applications of advances in power generation, energy storage, and power management and distribution to the Space Station are discussed.

  1. A high-throughput liquid bead array-based screening technology for Bt presence in GMO manipulation.

    PubMed

    Fu, Wei; Wang, Huiyu; Wang, Chenguang; Mei, Lin; Lin, Xiangmei; Han, Xueqing; Zhu, Shuifang

    2016-03-15

    The number of species and planting areas of genetically modified organisms (GMOs) has been rapidly developed during the past ten years. For the purpose of GMO inspection, quarantine and manipulation, we have now devised a high-throughput Bt-based GMOs screening method based on the liquid bead array. This novel method is based on the direct competitive recognition between biotinylated antibodies and beads-coupled antigens, searching for Bt presence in samples if it contains Bt Cry1 Aa, Bt Cry1 Ab, Bt Cry1 Ac, Bt Cry1 Ah, Bt Cry1 B, Bt Cry1 C, Bt Cry1 F, Bt Cry2 A, Bt Cry3 or Bt Cry9 C. Our method has a wide GMO species coverage so that more than 90% of the whole commercialized GMO species can be identified throughout the world. Under our optimization, specificity, sensitivity, repeatability and availability validation, the method shows a high specificity and 10-50 ng/mL sensitivity of quantification. We then assessed more than 1800 samples in the field and food market to prove capacity of our method in performing a high throughput screening work for GMO manipulation. Our method offers an applicant platform for further inspection and research on GMO plants.

  2. Improved Detection of Respiratory Pathogens by Use of High-Quality Sputum with TaqMan Array Card Technology.

    PubMed

    Wolff, Bernard J; Bramley, Anna M; Thurman, Kathleen A; Whitney, Cynthia G; Whitaker, Brett; Self, Wesley H; Arnold, Sandra R; Trabue, Christopher; Wunderink, Richard G; McCullers, Jon; Edwards, Kathryn M; Jain, Seema; Winchell, Jonas M

    2017-01-01

    New diagnostic platforms often use nasopharyngeal or oropharyngeal (NP/OP) swabs for pathogen detection for patients hospitalized with community-acquired pneumonia (CAP). We applied multipathogen testing to high-quality sputum specimens to determine if more pathogens can be identified relative to NP/OP swabs. Children (<18 years old) and adults hospitalized with CAP were enrolled over 2.5 years through the Etiology of Pneumonia in the Community (EPIC) study. NP/OP specimens with matching high-quality sputum (defined as ≤10 epithelial cells/low-power field [lpf] and ≥25 white blood cells/lpf or a quality score [q-score] definition of 2+) were tested by TaqMan array card (TAC), a multipathogen real-time PCR detection platform. Among 236 patients with matched specimens, a higher proportion of sputum specimens had ≥1 pathogen detected compared with NP/OP specimens in children (93% versus 68%; P < 0.0001) and adults (88% versus 61%; P < 0.0001); for each pathogen targeted, crossing threshold (CT) values were earlier in sputum. Both bacterial (361 versus 294) and viral detections (245 versus 140) were more common in sputum versus NP/OP specimens, respectively, in both children and adults. When available, high-quality sputum may be useful for testing in hospitalized CAP patients.

  3. How to change GEBCO outreach activities with Information technologies?

    NASA Astrophysics Data System (ADS)

    Chang, E.; Park, K.

    2014-12-01

    Since 1995, when National Geographic Information Project began, we have great advance in mapping itself and information service on the earth surface in Korea whether paper maps or online service map. By reviewing geological and mine-related information service in current and comparisons of demands, GEBCO outreach master plan has been prepared. Information service cannot be separated from data production and on dissemination policies. We suggest the potential impact of the changes in information technologies such as mobile service and data fusion, and big data on GEBCO maps based. Less cost and high performance in data service will stimulate more information service; therefore it is necessary to have more customer-oriented manipulation on the data. By inquiring questionnaire, we can draw the potential needs on GEBCO products in various aspects: such as education, accessibility. The gap between experts and non-experts will decrease by digital service from the private and public organizations such as international academic societies since research funds and policies tend to pursue "openness" and "interoperability" among the domains. Some background why and how to prepare outreach activities in GEBCO will be shown.

  4. Temporal relation between neural activity and neurite pruning on a numerical model and a microchannel device with micro electrode array.

    PubMed

    Kondo, Yohei; Yada, Yuichiro; Haga, Tatsuya; Takayama, Yuzo; Isomura, Takuya; Jimbo, Yasuhiko; Fukayama, Osamu; Hoshino, Takayuki; Mabuchi, Kunihiko

    2017-04-29

    Synapse elimination and neurite pruning are essential processes for the formation of neuronal circuits. These regressive events depend on neural activity and occur in the early postnatal days known as the critical period, but what makes this temporal specificity is not well understood. One possibility is that the neural activities during the developmentally regulated shift of action of GABA inhibitory transmission lead to the critical period. Moreover, it has been reported that the shifting action of the inhibitory transmission on immature neurons overlaps with synapse elimination and neurite pruning and that increased inhibitory transmission by drug treatment could induce temporal shift of the critical period. However, the relationship among these phenomena remains unclear because it is difficult to experimentally show how the developmental shift of inhibitory transmission influences neural activities and whether the activities promote synapse elimination and neurite pruning. In this study, we modeled synapse elimination in neuronal circuits using the modified Izhikevich's model with functional shifting of GABAergic transmission. The simulation results show that synaptic pruning within a specified period like the critical period is spontaneously generated as a function of the developmentally shifting inhibitory transmission and that the specific firing rate and increasing synchronization of neural circuits are seen at the initial stage of the critical period. This temporal relationship was experimentally supported by an in vitro primary culture of rat cortical neurons in a microchannel on a multi-electrode array (MEA). The firing rate decreased remarkably between the 18-25 days in vitro (DIV), and following these changes in the firing rate, the neurite density was slightly reduced. Our simulation and experimental results suggest that decreasing neural activity due to developing inhibitory synaptic transmission could induce synapse elimination and neurite pruning

  5. Surface Roughening of Nickel Cobalt Phosphide Nanowire Arrays/Ni Foam for Enhanced Hydrogen Evolution Activity.

    PubMed

    Wang, Xina; Tong, Rui; Wang, Yi; Tao, Hualong; Zhang, Zhihua; Wang, Hao

    2016-12-21

    Development of earth-abundant, efficient, and stable electrocatalysts for hydrogen evolution reactions (HER) in alkaline or even neutral pH electrolyte is very important for hydrogen production from water splitting. Construction of bimetal phosphides via tuning the bonding strength to hydrogen and increasing effective active sites through nanostructuring and surface engineering should lead to high HER activity. Here, ternary NiCoP nanowires (NWs) decorated by homogeneous nanoparticles have been obtained on Ni foam for a highly efficient HER property via long-term cyclic voltammetric (CV) sweeping. The electron density transfer between the positively charged Ni and Co and negatively charged P atoms, one-dimensional electron transfer channel of the NWs, and abundant active sites supplied by the nanoparticles and NWs endow the catalyst with low overpotentials of 43 and 118 mV to achieve the respective current densities of 10 and 100 mA cm(-2) together with long durability for at least 33 h in 1 M KOH. A cycled anodic dissolution-redeposition mechanism is disclosed for the formation of the NiCoP nanoparticles during the CV sweeping process. Such a surface roughening method is found to be adaptable to enhance the HER property of other phosphides, including Ni2P nanoplates/NF, NiCoP nanoparticles/NF, and CoP NW/NF.

  6. The Teacher as Re-Designer of Technology Integrated Activities for an Early Literacy Curriculum

    ERIC Educational Resources Information Center

    Cviko, Amina; McKenney, Susan; Voogt, Joke

    2013-01-01

    Though popular among children outside of school, Dutch teachers often struggle to offer technology integrated activities in the kindergarten classroom. Because involving teachers in development of technology integrated activities can support their implementation, this study examines teachers in the role of re-designing such activities. Two case…

  7. Integrated residential photovoltaic array development

    NASA Technical Reports Server (NTRS)

    Shepard, N. F., Jr.

    1981-01-01

    An advanced, universally-mountable, integrated residential photovoltaic array concept was defined based upon an in-depth formulation and evaluation of three candidate approaches which were synthesized from existing or proposed residential array concepts. The impact of module circuitry and process sequence is considered and technology gaps and performance drivers associated with residential photovoltaic array concepts are identified. The actual learning experience gained from the comparison of the problem areas of the hexagonal shingle design with the rectangular module design led to what is considered an advanced array concept. Building the laboratory mockup provided actual experience and the opportunity to uncover additional technology gaps.

  8. Recent Progress in Active Antenna Designs for the Long Wavelength Array (LWA)

    NASA Astrophysics Data System (ADS)

    Hicks, B. C.; Stewart, K. P.; Paravastu, N.; Bradley, R. F.; Parashare, C. R.; Erickson, W. C.; Gross, C.; Polisensky, E.; Crane, P. C.; Ray, P. S.; Kassim, N. E.; Weiler, K. W.

    2005-12-01

    We present new designs for active antenna systems optimized for HF/VHF radio astronomy, ionospheric science, space weather, and other radio science applications. Active antenna designs have been developed and tested which satisfy the need for high linearity and stability while achieving Galactic background dominated noise levels. The presence of very strong terrestrial radio-frequency interference (RFI), and world-wide propagation at these frequencies require that the preamplifiers have very high dynamic range. Distortion products must be below the Galactic background level for RFI mitigation techniques to be successful. Individual antennas should have broad response patterns to cover most of the sky without pointing mechanisms, but with decreased sensitivity at low elevations. Ideal designs would also be immune to environmental effects such as temperature variations and precipitation. For projects such as the LWA, where thousands of receptors will be needed, they must also be robust, inexpensive, and easy to manufacture and install. We discuss high-performance designs that are optimized for cost-sensitive applications such as the LWA. Basic research in astronomy is supported by the Office of Naval Research.

  9. Simultaneous SMM flat crystal spectrometer and Very Large Array observations of solar active regions

    NASA Technical Reports Server (NTRS)

    Lang, Kenneth R.; Willson, Robert F.; Smith, Kermit L.; Strong, Keith T.

    1987-01-01

    High-resolution images of the quiescent emission from two solar active regions at 20 cm (VLA) and soft X-ray (SMM FCS) wavelengths are compared. There are regions where the X-ray coronal loops have been completely imaged at 20 cm wavelength. In other regions, the X-ray radiation was detected without detectable 20 cm radiation, and vice versa. The X-ray data were used to infer average electron temperatures of about 3-million K and average electron densities of about 2.5 x 10 to the 9th/cu cm for the X-ray emitting plasma in the two active regions. The thermal bremsstrahlung of the X-ray emitting plasma is optically thin at 20 cm wavelength. The 20 cm brightness temperatures were always less than T(e), which is consistent with optically thin bremsstrahlung. The low T(B) can be explained if a higher, cooler plasma covers the hotter X-ray emitting plasma. Thermal gyroresonance radiation must account for the intense 20 cm radiation near and above sunspots where no X-ray radiation is detected.

  10. Active Fail-Safe Micro-Array Flow Control for Advanced Embedded Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Anderson, Bernhard H.; Mace, James L.; Mani, Mori

    2009-01-01

    The primary objective of this research effort was to develop and analytically demonstrate enhanced first generation active "fail-safe" hybrid flow-control techniques to simultaneously manage the boundary layer on the vehicle fore-body and to control the secondary flow generated within modern serpentine or embedded inlet S-duct configurations. The enhanced first-generation technique focused on both micro-vanes and micro-ramps highly-integrated with micro -jets to provide nonlinear augmentation for the "strength' or effectiveness of highly-integrated flow control systems. The study focused on the micro -jet mass flow ratio (Wjet/Waip) range from 0.10 to 0.30 percent and jet total pressure ratios (Pjet/Po) from 1.0 to 3.0. The engine bleed airflow range under study represents about a 10 fold decrease in micro -jet airflow than previously required. Therefore, by pre-conditioning, or injecting a very small amount of high-pressure jet flow into the vortex generated by the micro-vane and/or micro-ramp, active flow control is achieved and substantial augmentation of the controlling flow is realized.

  11. Idaho Nuclear Technology and Engineering Center Low-Activity Waste Process Technology Program FY-98 Status Report

    SciTech Connect

    Herbst, A.K.; McCray, J.A.; Rogers, A.Z.; Simmons, R.F.; Palethrope, S.J.

    1999-03-01

    The Low-Activity Waste Process Technology Program at the Idaho Nuclear Technology and Engineering Center (INTEC) anticipates that large volumes of low-level/low-activity wastes will need to be grouted prior to near-surface disposal. During fiscal year 1998, three grout formulations were studied for low-activity wastes derived from INTEC liquid sodium-bearing waste. Compressive strength and leach results are presented for phosphate bonding cement, acidic grout, and alkaline grout formulations. In an additional study, grout formulations are recommended for stabilization of the INTEC underground storage tank residual heels.

  12. Idaho Nuclear Technology and Engineering Center Low-Activity Waste Process Technology Program, FY-98 Status Report

    SciTech Connect

    Herbst, A.K.; Rogers, A.Z.; McCray, J.A.; Simmons, R.F.; Palethorpe, S.J.

    1999-03-01

    The Low-Activity Waste Process Technology Program at the Idaho Nuclear Technology and Engineering Center (INTEC) anticipates that large volumes of low-level/low-activity wastes will need to be grouted prior to near-surface disposal. During fiscal year 1998, three grout formulations were studied for low-activity wastes derived from INTEC liquid sodium-bearing waste. Compressive strength and leach results are presented for phosphate bonding cement, acidic grout, and alkaline grout formulations. In an additional study, grout formulations are recommended for stabilization of the INTEC underground storage tank residual heels.

  13. Active and Passive Technology Integration: A Novel Approach for Managing Technology's Influence on Learning Experiences in Context-Aware Learning Spaces

    ERIC Educational Resources Information Center

    Laine, Teemu H.; Nygren, Eeva

    2016-01-01

    Technology integration is the process of overcoming different barriers that hinder efficient utilisation of learning technologies. The authors divide technology integration into two components based on technology's role in the integration process. In active integration, the technology integrates learning resources into a learning space, making it…

  14. Double active control of the plasmonic resonance of a gold nanoparticle array

    NASA Astrophysics Data System (ADS)

    de Sio, Luciano; Cunningham, Alastair; Verrina, Vanessa; Tone, Caterina Maria; Caputo, Roberto; Bürgi, Thomas; Umeton, Cesare

    2012-11-01

    A two-fold active control of the plasmonic resonance of randomly distributed gold nanoparticles (GNPs) has been achieved. GNPs have been immobilized on an Indium Tin Oxide (ITO) coated glass substrate and then covered with a liquid crystalline compound. The system has been investigated by means of atomic force and scanning electron microscopy, revealing the presence of isolated and well distributed GNPs. The application of an external electric field to the sample has a two-fold consequence: the re-orientation of the hybrid-aligned liquid crystal layer and the formation of a carrier accumulation layer in the proximity of the ITO substrate. The refractive indices of both liquid crystal and accumulation layers are influenced by the applied field in a competitive way and produce a ``dancing behavior'' of the GNP's plasmonic resonance spectral position.

  15. Advanced Technological Education Program: 1995 Awards and Activities.

    ERIC Educational Resources Information Center

    National Science Foundation, Washington, DC. Directorate for Education and Human Resources.

    The Advanced Technological Education (ATE) program promotes exemplary improvement in advanced technological education at the national and regional level through support of curriculum development and program improvement at the undergraduate and secondary school levels, especially for technicians being educated for the high performance workplace of…

  16. Teachers' Activities in Technology-Based Mathematics Lessons

    ERIC Educational Resources Information Center

    Monaghan, John

    2004-01-01

    This paper focuses on high school mathematics teachers and what they do when they use digital technology in their lessons. It is essentially a discursive paper but it uses data from a project on teachers using technology to illustrate points. The main aim of the paper is to present an holistic account of factors influencing teachers' practice. A…

  17. Progress on the Aberystwyth electron counting array

    NASA Astrophysics Data System (ADS)

    Langstaff, D. P.; Evans, D. A.; Roberts, O. R.; Zhu, Xi

    2009-06-01

    An extended electron counting detector with a linear array of 1536 pixels across an active area of 38 mm×5 mm is presented. Also presented is an improved control electronics package, based on the National Instruments Compact RIO instrument programmed in Labview. Also presented is an application of the existing detector with 768 pixels, showing how the improvement in detection technology enables fresh insights into the formation of aluminium contacts on diamond.

  18. NiCo2S4 nanowires array as an efficient bifunctional electrocatalyst for full water splitting with superior activity

    NASA Astrophysics Data System (ADS)

    Liu, Danni; Lu, Qun; Luo, Yonglan; Sun, Xuping; Asiri, Abdullah M.

    2015-09-01

    The present communication reports the topotactic conversion of NiCo2O4 nanowires array on carbon cloth (NiCo2O4 NA/CC) into NiCo2S4 NA/CC, which is used as an efficient bifunctional electrocatalyst for water splitting with good durability and superior activity in 1.0 M KOH. This NiCo2S4 NA/CC electrode produces 100 mA cm-2 at an overpotential of 305 mV for hydrogen evolution and 100 mA cm-2 at an overpotential of 340 mV for oxygen evolution. To afford a 10 mA cm-2 water-splitting current, the alkaline water electrolyzer made from NiCo2S4 NA/CC needs a cell voltage of 1.68 V, which is 300 mV less than that for NiCo2O4 NA/CC, and has good stability.The present communication reports the topotactic conversion of NiCo2O4 nanowires array on carbon cloth (NiCo2O4 NA/CC) into NiCo2S4 NA/CC, which is used as an efficient bifunctional electrocatalyst for water splitting with good durability and superior activity in 1.0 M KOH. This NiCo2S4 NA/CC electrode produces 100 mA cm-2 at an overpotential of 305 mV for hydrogen evolution and 100 mA cm-2 at an overpotential of 340 mV for oxygen evolution. To afford a 10 mA cm-2 water-splitting current, the alkaline water electrolyzer made from NiCo2S4 NA/CC needs a cell voltage of 1.68 V, which is 300 mV less than that for NiCo2O4 NA/CC, and has good stability. Electronic supplementary information (ESI) available: Experimental section and ESI Figures. See DOI: 10.1039/c5nr04064g

  19. Relative dosimetry using active matrix flat-panel imager (AMFPI) technology.

    PubMed

    El-Mohri, Y; Antonuk, L E; Yorkston, J; Jee, K W; Maolinbay, M; Lam, K L; Siewerdsen, J H

    1999-08-01

    The first examination of the use of active matrix flat-panel arrays for dosimetry in radiotherapy is reported. Such arrays are under widespread development for diagnostic and radiotherapy imaging. In the current study, an array consisting of 512 x 512 pixels with a pixel pitch of 508 microm giving an area of 26 x 26 cm2 has been used. Each pixel consists of a light sensitive amorphous silicon (a-Si:H) photodiode coupled to an a-Si:H thin-film transistor. Data was obtained from the array using a dedicated electronics system allowing real-time data acquisition. In order to examine the potential of such arrays as quality assurance devices for radiotherapy beams, field profile data at photon energies of 6 and 15 MV were obtained as a function of field size and thickness of overlying absorbing material (solid water). Two detection configurations using the array were considered: a configuration (similar to the imaging configuration) in which an overlying phosphor screen is used to convert incident radiation to visible light photons which are detected by the photodiodes; and a configuration without the screen where radiation is directly sensed by the photodiodes. Compared to relative dosimetry data obtained with an ion chamber, data taken using the former configuration exhibited significant differences whereas data obtained using the latter configuration was generally found to be in close agreement. Basic signal properties, which are pertinent to dosimetry, have been investigated through measurements of individual pixel response for fluoroscopic and radiographic array operation. For signal levels acquired within the first 25% of pixel charge capacity, the degree of linear response with dose was found to be better than 99%. The independence of signal on dose rate was demonstrated by means of stability of pixel response over the range of dose rates allowed by the radiation source (80-400 MU/min). Finally, excellent long-term stability in pixel response, extending over a 2

  20. Image acquisition, geometric correction and display of images from a 2×2 x-ray detector array based on Electron Multiplying Charge Coupled Device (EMCCD) technology.

    PubMed

    Vasan, S N Swetadri; Sharma, P; Ionita, Ciprian N; Titus, A H; Cartwright, A N; Bednarek, D R; Rudin, S

    2013-03-06

    A high resolution (up to 11.2 lp/mm) x-ray detector with larger field of view (8.5 cm × 8.5 cm) has been developed. The detector is a 2 × 2 array of individual imaging modules based on EMCCD technology. Each module outputs a frame of size 1088 × 1037 pixels, each 12 bits. The frames from the 4 modules are acquired into the processing computer using one of two techniques. The first uses 2 CameraLink communication channels with each carrying information from two modules, the second uses a application specific custom integrated circuits, the Multiple Module Multiplexer Integrated Circuit (MMMIC), 3 of which are used to multiplex the data from 4 modules into one CameraLink channel. Once the data is acquired using either of the above mentioned techniques, it is decoded in the graphics processing unit (GPU) to form one single frame of size 2176 × 2074 pixels each 16 bits. Each imaging module uses a fiber optic taper coupled to the EMCCD sensor. To correct for mechanical misalignment between the sensors and the fiber optic tapers and produce a single seamless image, the images in each module may be rotated and translated slightly in the x-y plane with respect to each other. To evaluate the detector acquisition and correction techniques, an aneurysm model was placed over an anthropomorphic head phantom and a coil was guided into the aneurysm under fluoroscopic guidance using the detector array. Image sequences before and after correction are presented which show near-seamless boundary matching and are well suited for fluoroscopic imaging.

  1. How Does Technology-Enabled Active Learning Affect Undergraduate Students' Understanding of Electromagnetism Concepts?

    ERIC Educational Resources Information Center

    Dori, Yehudit Judy; Belcher, John

    2005-01-01

    Educational technology supports meaningful learning and enables the presentation of spatial and dynamic images, which portray relationships among complex concepts. The Technology-Enabled Active Learning (TEAL) Project at the Massachusetts Institute of Technology (MIT) involves media-rich software for simulation and visualization in freshman…

  2. The Federal Networking and Information Technology Research and Development Program: Funding Issues and Activities

    DTIC Science & Technology

    2004-07-01

    Information Technology Research and Development (NITRD) Program, to better reflect its expanded mission. The NITRD Program is composed of 12 agencies; its members work in collaboration to increase the overall effectiveness and productivity of federal information technology (IT) R&D. A National Coordinating Office coordinates the activities of the NITRD Program and reports to OSTP and the National Science and Technology

  3. TWO EPOCHS OF VERY LARGE ARRAY OBSERVATIONS OF WATER MASER EMISSION IN THE ACTIVE GALAXY NGC 6240

    SciTech Connect

    Hagiwara, Yoshiaki

    2010-12-15

    Studies of 22 GHz H{sub 2}O maser emission from the merging galaxy NGC 6240 with double nuclei are presented. Two epochs of Very Large Array (VLA) observations in the A-configuration in spectral-line mode were carried out at 0.1 arcsec resolution by covering the redshifted velocity range of {approx}300 km s{sup -1} with respect to the systemic velocity of the galaxy. The purpose of these new observations is twofold: to detect an H{sub 2}O maser that an earlier VLA observation pinpointed in the southern nucleus in the northern nucleus as well to clarify the kinematics of the double nuclei, and to understand the origin of the maser in the galaxy. In the second epoch, one velocity feature peaking at V{sub LSR} = 7491.1 km s{sup -1}, redshifted by {approx}200 km s{sup -1} relative to the systemic velocity, was detected only toward the southern nucleus. The detection of an H{sub 2}O maser feature at or near this velocity had never been reported in earlier observations. However, including the known velocity features at redshifted velocities, no other velocity features were observed toward either nuclei throughout these epochs. The maser remains unresolved at an angular resolution of {approx}0.''1, corresponding to a linear size of less than about 45 pc. The two epochs of VLA observations show that the maser intensity is variable on timescales of at least three months, while the correlation between the maser intensity and the radio continuum intensity is not certain from our data. It is plausible that the maser in NGC 6240 is associated with the activity of an active galactic nucleus in the southern nucleus. Alternatively, the maser can be explained by star-forming activity at the site of massive star formation in the galaxy.

  4. An aptamer based competition assay for protein detection using CNT activated gold-interdigitated capacitor arrays.

    PubMed

    Qureshi, Anjum; Roci, Irena; Gurbuz, Yasar; Niazi, Javed H

    2012-04-15

    An aptamer can specifically bind to its target molecule, or hybridize with its complementary strand. A target bound aptamer complex has difficulty to hybridize with its complementary strand. It is possible to determine the concentration of target based on affinity separation system for the protein detection. Here, we exploited this property using C-reactive protein (CRP) specific RNA aptamers as probes that were immobilized by physical adsorption on carbon nanotubes (CNTs) activated gold interdigitated electrodes of capacitors. The selective binding ability of RNA aptamer with its target molecule was determined by change in capacitance after allowing competitive binding with CRP and complementary RNA (cRNA) strands in pure form and co-mixtures (CRP:cRNA=0:1, 1:0, 1:1, 1:2 and 2:1). The sensor showed significant capacitance change with pure forms of CRP/cRNA while responses reduced considerably in presence of CRP:cRNA in co-mixtures (1:1 and 1:2) because of the binding competition. At a critical CRP:cRNA ratio of 2:1, the capacitance response was dramatically lost because of the dissociation of adsorbed aptamers from the sensor surface to bind when excess CRP. Binding assays showed that the immobilized aptamers had strong affinity for cRNA (K(d)=1.98 μM) and CRP molecules (K(d)=2.4 μM) in pure forms, but low affinity for CRP:cRNA ratio of 2:1 (K(d)=8.58 μM). The dynamic detection range for CRP was determined to be 1-8 μM (0.58-4.6 μg/capacitor). The approach described in this study is a sensitive label-free method to detect proteins based on affinity separation of target molecules that can potentially be used for probing molecular interactions.

  5. Scientific and Technological Information Activity in China (White Paper on Science and Technology : No.1, 1986.5)

    NASA Astrophysics Data System (ADS)

    Translated By Joho Kanri Editorial Committee

    This is a translation of Chapter 4 : Information Systems of Volume 5 : Environment and Resources in the first number of White Paper on Science and Technology edited in May 1986 by State Scientific and Technological Commission (SSTC). Scientific and technological information activity in China has progressed by keeping close cooperation among the Institute for Scientific and Technological Information in China (ISTIC) as a core organization, 33 information institutes under the control of each ministrial commission of The State Council and 35 information institutes of the local governments and cities. As a result of having promoted the information activities along with the guiding principle decided by the 5th National Conference on Scientific and Technological Information in July 1980, information business could be made a great contribution to political decision, national projects and economy stressing plan, technology introduction, etc. The Scientific and Technological Information Bureau of SSTC as a coordinating body proposed the following subjects as an important item for promoting future information business in China: standardization of abstract journals, bringing up of investigators and researchers, production of data bases and consolidation of international online retrieval services, step by step introduction of a charging system for information service, etc.

  6. Mobile satellite communications technology - A summary of NASA activities

    NASA Technical Reports Server (NTRS)

    Dutzi, E. J.; Knouse, G. H.

    1986-01-01

    Studies in recent years indicate that future high-capacity mobile satellite systems are viable only if certain high-risk enabling technologies are developed. Accordingly, NASA has structured an advanced technology development program aimed at efficient utilization of orbit, spectrum, and power. Over the last two years, studies have concentrated on developing concepts and identifying cost drivers and other issues associated with the major technical areas of emphasis: vehicle antennas, speech compression, bandwidth-efficient digital modems, network architecture, mobile satellite channel characterization, and selected space segment technology. The program is now entering the next phase - breadboarding, development, and field experimentation.

  7. Development of NANA: A Fast-Scintillator, Coincidence Gamma-ray Array for Radioactive Source Characterisation and Absolute Activity Measurements at the UK National Physical Laboratory

    NASA Astrophysics Data System (ADS)

    Regan, P. H.; Shearman, R.; Judge, S. M.; Lorusso, G.; Main, P.; Bell, S.; Collins, S. M.; Ivanov, P.; Jerome, S. M.; Keightley, J. D.; Larijani, C.; Lotay, G.; Pearce, A. K.

    2015-06-01

    A multi-detector modular coincidence gamma-ray spectrometer is being designed and constructed for use at the UK's National Physical Laboratory (NPL) for use in direct measurement and metrological standardisation of nuclear decay activities. In its first generation, the NPL National Nuclear Array (NANA) will consist of twelve individual halide scintillation detectors placed in a high-efficiency geometry around a well-defined central point source position. This brief conference paper provides details of the measured detector module and coincidence energy and timing responses for the LaBr3(Ce) detectors which will be used in the NANA array. Preliminary GEANT4 simulations of the array's full energy peak efficiency and expected gamma-ray coincidence response are also presented.

  8. A Review of Technology Education in Ireland; a Changing Technological Environment Promoting Design Activity

    ERIC Educational Resources Information Center

    Leahy, Keelin; Phelan, Pat

    2014-01-01

    In Ireland, Technology Education's structure and organisation across the levels of education is not delivered or governed in a coherent manner. Technology Education in primary level education, for students between 5 and 12 years of age, does not explicitly exist as a separate subject. In primary level education, Social, Environmental and…

  9. FENTON-DRIVEN REGENERATION OF GRANULAR ACTIVATED CARBON: A TECHNOLOGY OVERVIEW

    EPA Science Inventory

    A Fenton-driven mechanism for regenerating spent granular activated carbon (GAC) involves the combined, synergistic use of two reliable and well established treatment technologies - adsorption onto activated carbon and Fenton oxidation. During carbon adsorption treatment, enviro...

  10. Facile Synthesis of Vanadium-Doped Ni3S2 Nanowire Arrays as Active Electrocatalyst for Hydrogen Evolution Reaction.

    PubMed

    Qu, Yuanju; Yang, Mingyang; Chai, Jianwei; Tang, Zhe; Shao, Mengmeng; Kwok, Chi Tat; Yang, Ming; Wang, Zhenyu; Chua, Daniel; Wang, Shijie; Lu, Zhouguang; Pan, Hui

    2017-02-22

    Ni3S2 nanowire arrays doped with vanadium(V) are directly grown on nickel foam by a facile one-step hydrothermal method. It is found that the doping can promote the formation of Ni3S2 nanowires at a low temperature. The doped nanowires show excellent electrocatalytic performance toward hydrogen evolution reaction (HER), and outperform pure Ni3S2 and other Ni3S2-based compounds. The stability test shows that the performance of V-doped Ni3S2 nanowires is improved and stabilized after thousands of linear sweep voltammetry test. The onset potential of V-doped Ni3S2 nanowire can be as low as 39 mV, which is comparable to platinum. The nanowire has an overpotential of 68 mV at 10 mA cm(-2), a relatively low Tafel slope of 112 mV dec(-1), good stability and high Faradaic efficiency. First-principles calculations show that the V-doping in Ni3S2 extremely enhances the free carrier density near the Fermi level, resulting in much improved catalytic activities. We expect that the doping can be an effective way to enhance the catalytic performance of metal disulfides in hydrogen evolution reaction and V-doped Ni3S2 nanowire is one of the most promising electrocatalysts for hydrogen production.

  11. NiCo2S4 nanowires array as an efficient bifunctional electrocatalyst for full water splitting with superior activity.

    PubMed

    Liu, Danni; Lu, Qun; Luo, Yonglan; Sun, Xuping; Asiri, Abdullah M

    2015-10-07

    The present communication reports the topotactic conversion of NiCo2O4 nanowires array on carbon cloth (NiCo2O4 NA/CC) into NiCo2S4 NA/CC, which is used as an efficient bifunctional electrocatalyst for water splitting with good durability and superior activity in 1.0 M KOH. This NiCo2S4 NA/CC electrode produces 100 mA cm(-2) at an overpotential of 305 mV for hydrogen evolution and 100 mA cm(-2) at an overpotential of 340 mV for oxygen evolution. To afford a 10 mA cm(-2) water-splitting current, the alkaline water electrolyzer made from NiCo2S4 NA/CC needs a cell voltage of 1.68 V, which is 300 mV less than that for NiCo2O4 NA/CC, and has good stability.

  12. Integrated chassis control of active front steering and yaw stability control based on improved inverse nyquist array method.

    PubMed

    Zhu, Bing; Chen, Yizhou; Zhao, Jian

    2014-01-01

    An integrated chassis control (ICC) system with active front steering (AFS) and yaw stability control (YSC) is introduced in this paper. The proposed ICC algorithm uses the improved Inverse Nyquist Array (INA) method based on a 2-degree-of-freedom (DOF) planar vehicle reference model to decouple the plant dynamics under different frequency bands, and the change of velocity and cornering stiffness were considered to calculate the analytical solution in the precompensator design so that the INA based algorithm runs well and fast on the nonlinear vehicle system. The stability of the system is guaranteed by dynamic compensator together with a proposed PI feedback controller. After the response analysis of the system on frequency domain and time domain, simulations under step steering maneuver were carried out using a 2-DOF vehicle model and a 14-DOF vehicle model by Matlab/Simulink. The results show that the system is decoupled and the vehicle handling and stability performance are significantly improved by the proposed method.

  13. Integrated Chassis Control of Active Front Steering and Yaw Stability Control Based on Improved Inverse Nyquist Array Method

    PubMed Central

    2014-01-01

    An integrated chassis control (ICC) system with active front steering (AFS) and yaw stability control (YSC) is introduced in this paper. The proposed ICC algorithm uses the improved Inverse Nyquist Array (INA) method based on a 2-degree-of-freedom (DOF) planar vehicle reference model to decouple the plant dynamics under different frequency bands, and the change of velocity and cornering stiffness were considered to calculate the analytical solution in the precompensator design so that the INA based algorithm runs well and fast on the nonlinear vehicle system. The stability of the system is guaranteed by dynamic compensator together with a proposed PI feedback controller. After the response analysis of the system on frequency domain and time domain, simulations under step steering maneuver were carried out using a 2-DOF vehicle model and a 14-DOF vehicle model by Matlab/Simulink. The results show that the system is decoupled and the vehicle handling and stability performance are significantly improved by the proposed method. PMID:24782676

  14. First Year Observations of Antarctic Circumpolar Current Variability and Internal Wave Activity from the DIMES Mooring Array

    NASA Astrophysics Data System (ADS)

    Brearley, J. A.; Sheen, K. L.; Naveira-Garabato, A. C.

    2012-04-01

    A key component of DIMES (Diapycnal and Isopycnal Mixing Experiment in the Southern Ocean) is the deployment of a two-year cross-shaped mooring array in the Antarctic Circumpolar Current to the east of Drake Passage close to 57°W. Motivation for the cluster arises from the need to understand how eddies dissipate in the Southern Ocean, and specifically how much energy is extracted from the mesoscale by breaking internal waves, which in turn leads to turbulent mixing. The location of the mooring cluster was chosen to fulfil these objectives, being situated in a region of pronounced finestructure with high eddy kinetic energy and rough topography. The array, comprising 34 current meters and Microcats and a downward-looking ADCP, was first deployed in December 2009 and serviced in December 2010. Time series of current meter results from the most heavily-instrumented 'C' mooring indicate that a strong (up to 80 cms-1) surface-intensified north-eastward directed ACC occupies the region for most of the year, with over 85% of the variability in current speed being accounted for by equivalent barotropic fluctuations. A strong mean poleward heat flux is observed at the site, which compares favourably in magnitude with literature results from other ACC locations. Interestingly, four episodes of mid-depth (~2000 m) current speed maxima, each of a few days duration, were found during the 360-day time series, a situation also observed by the lowered ADCP during mooring servicing in December 2010. Early results indicate that these episodes, which coincide with time minima in stratification close to 2000 m, could profoundly influence the nature of eddy-internal wave interactions at these times. Quantification of the energy budget at the mooring cluster has been a key priority. When compared with previous moorings located in Drake Passage (Bryden, 1977), a near threefold-increase in mean eddy kinetic energy (EKE) is observed despite a small reduction in the mean kinetic energy

  15. Application of Lectin Array Technology for Biobetter Characterization: Its Correlation with FcγRIII Binding and ADCC

    PubMed Central

    Roucka, Markus; Zimmermann, Klaus; Fido, Markus; Nechansky, Andreas

    2016-01-01

    Lectin microarray technology was applied to compare the glycosylation pattern of the monoclonal antibody MB311 expressed in SP2.0 cells to an antibody-dependent cellular cytotoxic effector function (ADCC)-optimized variant (MB314). MB314 was generated by a plant expression system that uses genetically modified moss protoplasts (Physcomitrella patens) to generate a de-fucosylated version of MB311. In contrast to MB311, no or very low interactions of MB314 with lectins Aspergillus oryzae l-fucose (AOL), Pisum sativum agglutinin (PSA), Lens culinaris agglutinin (LCA), and Aleuria aurantia lectin (AAL) were observed. These lectins are specific for mono-/biantennary N-glycans containing a core fucose residue. Importantly, this fucose indicative lectin-binding pattern correlated with increased MB314 binding to CD16 (FcγRIII; receptor for the constant region of an antibody)—whose affinity is mediated through core fucosylation—and stronger ADCC. In summary, these results demonstrate that lectin microarrays are useful orthogonal methods during antibody development and for characterization. PMID:28029136

  16. Large solar arrays

    NASA Technical Reports Server (NTRS)

    Crabtree, W. L.

    1980-01-01

    A spectrophotovoltaic converter, a thermophotovoltaic converter, a cassegrainian concentrator, a large silicon cell blanket, and a high flux approach are among the concepts being investigated as part of the multihundred kW solar array program for reducing the cost of photovoltaic energy in space. These concepts involve a range of technology risks, the highest risk being represented by the thermophotovoltaics and spectrophotovoltaics approaches which involve manipulation to of the incoming spectrum to enhance system efficiency. The planar array (solar blanket) has no technology risk and a moderate payback. The primary characteristics, components, and technology concerns of each of these concepts are summarized. An orbital power platform mission in the late 1980's is being used to allow a coherent technology advancement program in order to achieve a ten year life with maintenance at a capital recurring cost of $30/watt based on 1978 dollars.

  17. Oil atlas: National Petroleum Technology Office activities across the United States

    SciTech Connect

    Tiedemann, H.A.

    1998-03-01

    Petroleum imports account for the largest share of the US trade deficit. Over one-third of the 1996 merchandise trade deficit is attributed to imported oil. The good news is that substantial domestic oil resources, both existing and yet-to-be-discovered, can be recovered using advanced petroleum technologies. The Energy Information Agency estimates that advanced technologies can yield 10 billion additional barrels, equal to $240 billion in import offsets. The US Department of Energy`s National Petroleum Technology Office works with industry to develop advanced petroleum technologies and to transfer successful technologies to domestic oil producers. This publication shows the locations of these important technology development efforts and lists DOE`s partners in this critical venture. The National Petroleum Technology Office has 369 active technology development projects grouped into six product lines: Advanced Diagnostics and Imaging Systems; Advanced Drilling, Completion, and Stimulation; Reservoir Life Extension and Management; Emerging Processing Technology Applications; Effective Environmental Protection; and Crosscutting Program Areas.

  18. Idaho Nuclear Technology and Engineering Center Low-Activity Waste Process Technology Program FY-99 Status Report

    SciTech Connect

    A. K. Herbst; J. A. McCray; R. J. Kirkham; J. Pao; S. H. Hinckley

    1999-09-30

    The Low-Activity Waste Process Technology Program at the Idaho Nuclear Technology and Engineering Center (INTEC) anticipates that large volumes of low-level/low-activity wastes will need to be grouted prior to near-surface disposal. During fiscal year 1999, grout formulations were studied for transuranic waste derived from INTEC liquid sodium-bearing waste and for projected newly generated low-level liquid waste. Additional studies were completed on radionuclide leaching, microbial degradation, waste neutralization, and a small mockup for grouting the INTEC underground storage tank residual heels.

  19. Idaho Nuclear Technology and Engineering Center Low-Activity Waste Process Technology Program FY-99 Status Report

    SciTech Connect

    Herbst, Alan Keith; Mc Cray, John Alan; Kirkham, Robert John; Pao, Jenn Hai; Hinckley, Steve Harold

    1999-10-01

    The Low-Activity Waste Process Technology Program at the Idaho Nuclear Technology and Engineering Center (INTEC) anticipates that large volumes of low-level/low-activity wastes will need to be grouted prior to near-surface disposal. During fiscal year 1999, grout formulations were studied for transuranic waste derived from INTEC liquid sodium-bearing waste and for projected newly generated low-level liquid waste. Additional studies were completed on radionuclide leaching, microbial degradation, waste neutralization, and a small mockup for grouting the INTEC underground storage tank residual heels.

  20. 3 CFR - Designation of the National Science and Technology Council to Coordinate Certain Activities Under...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Technology Council to CoordinateCertain Activities Under the Arctic Research and Policy Act of 1984... 3 The President 1 2011-01-01 2011-01-01 false Designation of the National Science and Technology Council to Coordinate Certain Activities Under the Arctic Research and Policy Act of 1984...