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Sample records for range system viability

  1. Range and range rate system

    NASA Technical Reports Server (NTRS)

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

    1988-01-01

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

  2. Range Safety Systems

    NASA Technical Reports Server (NTRS)

    Schrock, Kenneth W.; Humphries, Ricky H. (Technical Monitor)

    2002-01-01

    The high kinetic and potential energy of a launch vehicle mandates there be a mechanism to minimize possible damage to provide adequate safety for the launch facilities, range, and, most importantly, the general public. The Range Safety System, sometimes called the Flight Termination System or Flight Safety System, provides the required level of safety. The Range Safety System section of the Avionics chapter will attempt to describe how adequate safety is provided, the system's design, operation, and it's interface with the rest of the launch vehicle.

  3. Nonscanning confocal ranging system

    NASA Astrophysics Data System (ADS)

    Sun, P. C.; Arons, E.

    1995-03-01

    We demonstrate a nonscanning confocal ranging system based on spatially incoherent interferometry. Such a system has significant advantages over the conventional confocal imaging system and other interferometric systems. We develop the theory in terms of coherence cells and demonstrate the equivalence of our method to the conventional confocal methods. Experimental results are also provided.

  4. Laser Ranging System

    NASA Technical Reports Server (NTRS)

    Russell, J. K.

    1986-01-01

    Laser system points and focuses TV camera. Ranger is modified stock distance-measuring unit mounted on and electrically connected to television camera. Effective over target range of 3 to 500 ft. (approximately 1 to 150m). Developed for television monitoring of nearby objects from Space Shuttle. Super-imposes range and range-rate (speed of approach or recession) data on television image of target. Principle adaptable to applications such as proximity warning and robot control.

  5. Improved ranging systems

    NASA Technical Reports Server (NTRS)

    Young, Larry E.

    1989-01-01

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

  6. [Viability of facultative anaerobic bacteria in commercial transport systems].

    PubMed

    Gruber, I M; Dmitrieva, M N; Gavrilova, N A; Zhigunova, O V; Nisilevich, V F

    2001-01-01

    The possibilities of the transport systems manufactured by Copan (Italy) and Deltalab (Spain) were studied on 15 microbial strains: representatives of the family Enterobacteriaceae (enterobacterial swabs with Cary-Blair medium) and the genus Streptococcus, as well as the species Neisseria meningitidis, Haemophilus influenzae (universal swabs with charcoal-enriched Amies medium). Microorganisms were shown to retain their viability (in colony-forming units, %) for 48 hours in the systems of both firms. H. influenzae exhibited greater viability in the system manufactured by Copan than in that manufactured by Deltalab (respectively, 62% and 28% in 24 hours, 19% and 6% in 48 hours).

  7. Fever-range hyperthermia vs. hypothermia effect on cancer cell viability, proliferation and HSP90 expression.

    PubMed

    Kalamida, Dimitra; Karagounis, Ilias V; Mitrakas, Achilleas; Kalamida, Sofia; Giatromanolaki, Alexandra; Koukourakis, Michael I

    2015-01-01

    The current study examines the effect of fever-range hyperthermia and mild hypothermia on human cancer cells focusing on cell viability, proliferation and HSP90 expression. A549 and H1299 lung carcinoma, MCF7 breast adenocarcinoma, U87MG and T98G glioblastoma, DU145 and PC3 prostate carcinoma and MRC5 normal fetal lung fibroblasts cell lines were studied. After 3-day exposure to 34°C, 37°C and 40°C, cell viability was determined. Cell proliferation (ki67 index), apoptosis (Caspase 9) and HSP90 expression was studied by confocal microscopy. Viability/proliferation experiments demonstrated that MRC5 fibroblasts were extremely sensitive to hyperthermia, while they were the most resistant to hypothermia. T98G and A549 were thermo-tolerant, the remaining being thermo-sensitive to a varying degree. Nonetheless, as a universal effect, hypothermia reduced viability/proliferation in all cell lines. Hyperthermia sharply induced Caspase 9 in the U87MG most thermo-sensitive cell line. In T98G and A549 thermo-tolerant cell lines, the levels of Caspase 9 declined. Moreover, hyperthermia strongly induced the HSP90 levels in T98G, whilst a sharp decrease was recorded in the thermo-sensitive PC3 and U87MG cell lines. Hyperthermia sensitized thermo-sensitive cancer cell lines to cisplatin and temozolomide, whilst its sensitizing effect was diminished in thermo-tolerant cell lines. The existence of thermo-tolerant and thermo-sensitive cancer cell lines was confirmed, which further encourages research to classify human tumor thermic predilection for patient stratification in clinical trials. Of interest, mild hypothermia had a universal suppressing effect on cancer cell proliferation, further supporting the radio-sensitization hypothesis through reduction of oxygen and metabolic demands.

  8. Economic viability of beef cattle grazing systems under prolonged drought

    USDA-ARS?s Scientific Manuscript database

    Prolonged drought in the Southern Great Plains of the USA in recent years has raised concerns about vulnerability of beef cattle grazing systems under adverse climate change. To help address the economic viability of beef grazing operations in the Southern Great Plains, this paper provides an econom...

  9. A Long-Range Precision Ranging System

    NASA Technical Reports Server (NTRS)

    Easterling, Mahlon

    1961-01-01

    A technique is presented that may be used for precision real-time continuous range measuring at long ranges. The technique uses a carrier that is phase modulated by a pseudo-random binary sequence. The characteristics of the sequence that make it acquirable are discussed. The general form of a receiver capable of tracking the carrier is given and is shown to be a kind of phase-locked loop. A two-loop system capable of tracking a pseudo-random sequence and its clock is given. The combination of the receiver and the sequence tracking system form a ranging receiver. The power division necessary between the carrier and the sidebands is shown to be determined by the noise bandwidths of the two tracking systems. The bandwidths necessary for tracking space probes and Earth satellites are given and some experiments in radar-tracking Earth satellites are described. Based on these experiments, estimates are made of the useful range of such a system in tracking space probes.

  10. Micron Accurate Absolute Ranging System: Range Extension

    NASA Technical Reports Server (NTRS)

    Smalley, Larry L.; Smith, Kely L.

    1999-01-01

    The purpose of this research is to investigate Fresnel diffraction as a means of obtaining absolute distance measurements with micron or greater accuracy. It is believed that such a system would prove useful to the Next Generation Space Telescope (NGST) as a non-intrusive, non-contact measuring system for use with secondary concentrator station-keeping systems. The present research attempts to validate past experiments and develop ways to apply the phenomena of Fresnel diffraction to micron accurate measurement. This report discusses past research on the phenomena, and the basis of the use Fresnel diffraction distance metrology. The apparatus used in the recent investigations, experimental procedures used, preliminary results are discussed in detail. Continued research and equipment requirements on the extension of the effective range of the Fresnel diffraction systems is also described.

  11. Single-cell viability assessment with a novel spectro-imaging system.

    PubMed

    Matsuoka, Hideaki; Kosai, Yuri; Saito, Mikako; Takeyama, Norihide; Suto, Hiroshi

    2002-04-11

    Single-cell viability assessment by means of plural dye probes require the spectral and temporal analysis of microscopic images of the test cells. To meet this requirement, we have developed a simple and compact spectro-imaging system using an image slicer and a grism. The image slicer was made of a bundle of 100 optical fibers. The field of view is divided into 10 x 10 sections. The spectral data of each section could be recorded every 5 s in the range from 400 to 800 nm at 5 nm resolution. The viability changes of yeast or tobacco single-cells were measured with this system. Using BY-2 cells, for example, the response to a chemical stress of saponin was measured by means of two fluorescent probes. The spectral-spatial-temporal data of fluorescein and DNA bound ethidium bromide provided us with useful information about the dynamic change of cell membrane permeability from which the cell viability was assessed.

  12. Non-disruptive measurement system of cell viability in bioreactors

    NASA Astrophysics Data System (ADS)

    Rudek, F.; Nelsen, B. L.; Baselt, T.; Berger, T.; Wiele, M.; Prade, I.; Hartmann, P.

    2016-04-01

    Nutrient and oxygen transport, as well as the removal of metabolic waste are essential processes to support and maintain viable tissue. Current bioreactor technology used to grow tissue cultures in vitro has a fundamental limit to the thickness of tissues. Based on the low diffusion limit of oxygen a maximum tissue thickness of 200 μm is possible. The efficiency of those systems is currently under investigation. During the cultivation process of the artificial tissue in bioreactors, which lasts 28 days or longer, there are no possibilities to investigate the viability of cells. This work is designed to determine the influence of a non-disruptive cell viability measuring system on cellular activity. The measuring system uses a natural cellular marker produced during normal metabolic activity. Nicotinamide adenine dinucleotide (NADH) is a coenzyme naturally consumed and produced during cellular metabolic processes and has thoroughly been studied to determine the metabolic state of a cell. Measuring the fluorescence of NADH within the cell represents a non-disruptive marker for cell viability. Since the measurement process is optical in nature, NADH fluorescence also provides a pathway for sampling at different measurement depths within a given tissue sample. The measurement system we are using utilizes a special UV light source, to excite the NADH fluorescence state. However, the high energy potentially alters or harms the cells. To investigate the influence of the excitation signal, the cells were irradiated with a laser operating at a wavelength of 355 nm and examined for cytotoxic effects. The aim of this study was to develop a non-cytotoxic system that is applicable for large-scale operations during drug-tissue interaction testing.

  13. Demonstrating the Viability and Affordability of Nuclear Surface Power Systems

    NASA Technical Reports Server (NTRS)

    Vandyke, Melissa K.

    2006-01-01

    A set of tasks have been identified to help demonstrate the viability, performance, and affordability of surface fission systems. Completion of these tasks will move surface fission systems closer to reality by demonstrating affordability and performance potential. Tasks include fabrication and test of a 19-pin section of a Surface Power Unit Demonstrator (SPUD); design, fabrication, and utilization of thermal simulators optimized for surface fission' applications; design, fabrication, and utilization of GPHS module thermal simulators; design, fabrication, and test of a fission surface power system shield; and work related to potential fission surface power fuel/clad systems. Work on the SPUD will feed directly into joint NASA MSFC/NASA GRC fabrication and test of a surface power plant Engineering Development Unit (EDU). The goal of the EDU will be to perform highly realistic thermal, structural, and electrical testing on an integrated fission surface power system. Fission thermal simulator work will help enable high fidelity non-nuclear testing of pumped NaK surface fission power systems. Radioisotope thermal simulator work will help enable design and development of higher power radioisotope systems (power ultimately limited by Pu-238 availability). Shield work is designed to assess the potential of using a water neutron shield on the surface of the moon. Fuels work is geared toward assessing the current potential of using fuels that have already flown in space.

  14. Demonstrating the Viability and Affordability of Nuclear Surface Power Systems

    NASA Technical Reports Server (NTRS)

    Vandyke, Melissa K.

    2006-01-01

    A set of tasks have been identified to help demonstrate the viability, performance, and affordability of surface fission systems. Completion of these tasks will move surface fission systems closer to reality by demonstrating affordability and performance potential. Tasks include fabrication and test of a 19-pin section of a Surface Power Unit Demonstrator (SPUD); design, fabrication, and utilization of thermal simulators optimized for surface fission' applications; design, fabrication, and utilization of GPHS module thermal simulators; design, fabrication, and test of a fission surface power system shield; and work related to potential fission surface power fuel/clad systems. Work on the SPUD will feed directly into joint NASA MSFC/NASA GRC fabrication and test of a surface power plant Engineering Development Unit (EDU). The goal of the EDU will be to perform highly realistic thermal, structural, and electrical testing on an integrated fission surface power system. Fission thermal simulator work will help enable high fidelity non-nuclear testing of pumped NaK surface fission power systems. Radioisotope thermal simulator work will help enable design and development of higher power radioisotope systems (power ultimately limited by Pu-238 availability). Shield work is designed to assess the potential of using a water neutron shield on the surface of the moon. Fuels work is geared toward assessing the current potential of using fuels that have already flown in space.

  15. Influence of a range of extreme environmental factors on tripartite lichen Peltigera aphthosa thallus viability

    NASA Astrophysics Data System (ADS)

    Irina, Insarova; Dyakov, Max; Ptushenko, Vasiliy; Shtaer, Oksana

    Lichens are symbiotic organisms consisting of at least two genetic different partners: a heterotrophic fungus (mycobiont) and a phototrophic alga or cyanobacterium (photobiont). Lichens are ubiquitous at global scale. These symbiotic organisms represent the dominant type of “vegetation” at 8 - 10% of land (Larson, 1987). Abiotic stress’ resistance is notable for lichens among all eukaryotes. Lichens are often called “extremophiles” for their ability to acclimate the most severe environmental conditions. These features allow regarding lichens as a group of organisms which is potentially able to keep viability under open space conditions and to survive within Mars-like atmosphere types. The research presented was carried out in the network of spacecraft Bion-1 experiments involving the investigation of physiological and ultrastructural changes in biological objects survivable under open space conditions. Similar researches were already conducted on bipartite lichen species. The most attention was paid to the influence of UV and other space radiation types on lichen viability in those works. Thus we have taken tripartite lichen Peltigera aphthosa as a main research object and temperature fluctuations from extremely high to extremely low values in accordance to solar and umbral orbit sides - for the main extreme environmental factors. These factors were the less studied in previous works. During the research the influence of incubation under anaerobic conditions, multi-time effects of high and low temperatures and their interchange on respiratory metabolism, photosynthetic apparatus condition and the ultrastructure of P. aphthosa thalli was assessed. The data obtained demonstrate that activity either mycobiont or photobiont in tripartite lichen Peltigera aphthosa keep near unchanged under influence of all stress factors explored on dry thalli.

  16. Near-infrared hyperspectral imaging system coupled with multivariate methods to predict viability and vigor in muskmelon seeds

    USDA-ARS?s Scientific Manuscript database

    A near-infrared (NIR) hyperspectral imaging (HSI) system was used to predict viability and vigor (in term of germination periods) in muskmelon seeds. Hyperspectral images of muskmelon seeds were acquired using a NIR push-broom HSI system covering the spectral range of 948–2494 nm. After NIR spectra ...

  17. Identification, Description, and Perceived Viability of K-12 Consolidated Catholic School Systems

    ERIC Educational Resources Information Center

    Britt, Kenith C.

    2011-01-01

    Limited research has been conducted on Catholic school viability (James, Tichy, Collins, & Schwob, 2008; Lundy, 1999) and Catholic school systems (Goldschmidt, O'Keefe, & Walsh, 2004). But no research studies have investigated the viability of the consolidated Catholic school system (DeFiore, Convey, & Schuttloffel, 2009). This study investigates…

  18. Identification, Description, and Perceived Viability of K-12 Consolidated Catholic School Systems

    ERIC Educational Resources Information Center

    Britt, Kenith C.

    2011-01-01

    Limited research has been conducted on Catholic school viability (James, Tichy, Collins, & Schwob, 2008; Lundy, 1999) and Catholic school systems (Goldschmidt, O'Keefe, & Walsh, 2004). But no research studies have investigated the viability of the consolidated Catholic school system (DeFiore, Convey, & Schuttloffel, 2009). This study investigates…

  19. Long range inductive power transfer system

    NASA Astrophysics Data System (ADS)

    Lawson, James; Pinuela, Manuel; Yates, David C.; Lucyszyn, Stepan; Mitcheson, Paul D.

    2013-12-01

    We report upon a recently developed long range inductive power transfer system (IPT) designed to power remote sensors with mW level power consumption at distances up to 7 m. In this paper an inductive link is established between a large planar (1 × 1 m) transmit coil (Tx) and a small planer (170 × 170 mm) receiver coil (Rx), demonstrating the viability of highly asymmetrical coil configurations that real-world applications such as sensor networks impose. High Q factor Tx and Rx coils required for viable power transfer efficiencies over such distances are measured using a resonant method. The applicability of the Class-E amplifier in very low magnetic coupling scenarios and at the high frequencies of operation required for high Q operation is demonstrated by its usage as the Tx coil driver.

  20. Viability of long range dragonfly migration across the Indian Ocean: An energetics perspective

    NASA Astrophysics Data System (ADS)

    Saha, Sandeep; Nirwal, Satvik

    2016-11-01

    Recently Pantala flavescens (dragonflies) have been reported to migrate in millions from India to Eastern Africa on a multigenerational migratory circuit of length 14000-18000 kms. We attempt to understand the ability of dragonflies to perform long range migration by examining the energetics using computer simulations. In absence of a theory for long range insect migrations, we resort to the extensive literature on long range bird migration from the energetics perspective. The flight energetics depends upon instantaneous power and velocity. The mechanical flight power is computed from the power curve which is then converted to mass depletion using Brequet's equation. However, the mechanical flight power itself depends upon the instantaneous velocity which can vary depending upon the current mass. In order to predict the range in our simulations, we assume that the insect progressively tries to achieve the maximum range velocity. The results indicate that the migration range is approximately 1260 kms in 70 hours based on the true airspeed. However, our analysis is restricted by the lack of data and certain caveats in drag prediction and basal metabolism rate.

  1. ASTP ranging system mathematical model

    NASA Technical Reports Server (NTRS)

    Ellis, M. R.; Robinson, L. H.

    1973-01-01

    A mathematical model is presented of the VHF ranging system to analyze the performance of the Apollo-Soyuz test project (ASTP). The system was adapted for use in the ASTP. The ranging system mathematical model is presented in block diagram form, and a brief description of the overall model is also included. A procedure for implementing the math model is presented along with a discussion of the validation of the math model and the overall summary and conclusions of the study effort. Detailed appendices of the five study tasks are presented: early late gate model development, unlock probability development, system error model development, probability of acquisition and model development, and math model validation testing.

  2. Laser system of extended range

    NASA Technical Reports Server (NTRS)

    Lehr, C. G.

    1972-01-01

    A pulsed laser system was developed for range measurements from the earth to retroreflecting satellites at distances up to that of the moon. The system has a transportable transmitter unit that can be moved from one location to another. This unit consists of a 0.2 m coude refractor and a high radiance, neodymium-glass, frequency doubled laser that operates in a single transverse mode. It can be used for lunar or distant satellite ranging at any observatory that has a telescope with an aperture diameter of about 1.5 m for the detection of the laser return pulses. This telescope is utilized in the same manner customarily employed for the observation of celestial objects. A special photometric package and the associated electronics are provided for laser ranging.

  3. Viability assessment of bacteria using long-range surface plasmon waveguide biosensors

    NASA Astrophysics Data System (ADS)

    Béland, Paul; Berini, Pierre

    2017-01-01

    We demonstrate that long-range surface plasmon waveguide biosensors are useful to monitor the quiver of immobilized live bacteria in buffer and in human urine. First, the biosensor captures bacteria selectively, based on gram, using antibodies against gram adsorbed on the surface of the waveguide through Protein G coupling. Then, analysis of the noise present on the optical output signal reveals quiver of bacteria immobilized on the waveguide. Live bacteria produce a noisy signature compared to baseline levels. The standard deviation over time of the optical power output from the biosensor increased by factors of 3-60 over that of the baseline level for Staphylococcus epidermidis and Escherichia coli immobilized selectively on waveguides.

  4. Preliminary error budget for an optical ranging system: Range, range rate, and differenced range observables

    NASA Technical Reports Server (NTRS)

    Folkner, W. M.; Finger, M. H.

    1990-01-01

    Future missions to the outer solar system or human exploration of Mars may use telemetry systems based on optical rather than radio transmitters. Pulsed laser transmission can be used to deliver telemetry rates of about 100 kbits/sec with an efficiency of several bits for each detected photon. Navigational observables that can be derived from timing pulsed laser signals are discussed. Error budgets are presented based on nominal ground stations and spacecraft-transceiver designs. Assuming a pulsed optical uplink signal, two-way range accuracy may approach the few centimeter level imposed by the troposphere uncertainty. Angular information can be achieved from differenced one-way range using two ground stations with the accuracy limited by the length of the available baseline and by clock synchronization and troposphere errors. A method of synchronizing the ground station clocks using optical ranging measurements is presented. This could allow differenced range accuracy to reach the few centimeter troposphere limit.

  5. Viability of a Reusable In-Space Transportation System

    NASA Technical Reports Server (NTRS)

    Jefferies, Sharon A.; McCleskey, Carey M.; Nufer, Brian M.; Lepsch, Roger A.; Merrill, Raymond G.; North, David D.; Martin, John G.; Komar, David R.

    2015-01-01

    The National Aeronautics and Space Administration (NASA) is currently developing options for an Evolvable Mars Campaign (EMC) that expands human presence from Low Earth Orbit (LEO) into the solar system and to the surface of Mars. The Hybrid in-space transportation architecture is one option being investigated within the EMC. The architecture enables return of the entire in-space propulsion stage and habitat to cis-lunar space after a round trip to Mars. This concept of operations opens the door for a fully reusable Mars transportation system from cis-lunar space to a Mars parking orbit and back. This paper explores the reuse of in-space transportation systems, with a focus on the propulsion systems. It begins by examining why reusability should be pursued and defines reusability in space-flight context. A range of functions and enablers associated with preparing a system for reuse are identified and a vision for reusability is proposed that can be advanced and implemented as new capabilities are developed. Following this, past reusable spacecraft and servicing capabilities, as well as those currently in development are discussed. Using the Hybrid transportation architecture as an example, an assessment of the degree of reusability that can be incorporated into the architecture with current capabilities is provided and areas for development are identified that will enable greater levels of reuse in the future. Implications and implementation challenges specific to the architecture are also presented.

  6. Short-range communication system

    NASA Technical Reports Server (NTRS)

    Alhorn, Dean C. (Inventor); Howard, David E. (Inventor); Smith, Dennis A. (Inventor)

    2012-01-01

    A short-range communication system includes an antenna, a transmitter, and a receiver. The antenna is an electrical conductor formed as a planar coil with rings thereof being uniformly spaced. The transmitter is spaced apart from the plane of the coil by a gap. An amplitude-modulated and asynchronous signal indicative of a data stream of known peak amplitude is transmitted into the gap. The receiver detects the coil's resonance and decodes same to recover the data stream.

  7. Assessing the Practicality and Viability of Basalt Vesicle Paleoaltimetry in Solving Regional Tectonic Problems in the Basin and Range

    NASA Astrophysics Data System (ADS)

    Niemi, N.; Sahagian, D.; Proussevitch, A.; Carlson, W.

    2005-12-01

    Understanding the paleoelevation history of orogens is fundamental to answering a number of significant questions about continental deformation. Most paleoaltimeters rely on proxies for measuring paleoelevation that may be affected by factors other than elevation, such as climate. The basalt vesicle paleoaltimeter avoids problems associated with such proxies by directly measuring the paleo-atmospheric pressure recorded by vesicle size-distributions in basalt lava flows. Comparison of "paleoelevation" determinations from recent lava flows with their actual modern elevations on Hawaii has demonstrated the potential of this technique. Application to a study of the evolution of Cenozoic topography in the Basin and Range has revealed some of the practical limitations to the technique. Mafic lavas in the Basin and Range are more silicic than the basalts erupted on Hawaii. As a result, typical mafic lava flows in the Basin and Range are thicker, have less well-defined flow stratigraphy, and are less well-preserved than basaltic lava flows on Hawaii. Each of these factors increases the difficulty of locating a suitable sampling site for basalt vesicle paleoaltimetry. In an attempt to ameliorate these difficulties, a number of guidelines for sampling for basalt paleoaltimetry can be applied. Where available, stacks of flows offer the best opportunity for finding preserved flow tops and bottoms. The suitability of the flow for sampling is inversely proportional to SiO2 content, where samples with SiO2 < 50% are best, and samples with SiO2 > 54% are unsuitable. Samples in between this range display vesicles in the field, but the vesicle sizes are near the resolution of CT scans. Paleoelevation determination from young mafic lava flows of a variety of compositions will be presented to assess the viability of this technique to a wider range of lithologies, and thus a wider range of potential tectonic problems.

  8. Culturing thick brain slices: an interstitial 3D microperfusion system for enhanced viability.

    PubMed

    Rambani, Komal; Vukasinovic, Jelena; Glezer, Ari; Potter, Steve M

    2009-06-15

    and catabolites. We examined the utility of this perfusion method to enhance the viability of the thick organotypic brain slice cultures after 2 days and 5 days in vitro (DIV). We investigated the range of amenable flow rates that enhance the viability of 700 microm thick organotypic brain slices compared to the unperfused control cultures. Our perfusion method allows up to 84.6% viability (p<0.01) and up to 700 microm thickness, even after 5 DIV. Our results also confirm that these cultures are functionally active and have their in vivo cyto-architecture preserved. Prolonged viability of thick organotypic brain slice cultures will benefit scientists investigating network properties of intact organotypic neuronal networks in a reliable and repeatable manner.

  9. Culturing thick brain slices: An interstitial 3D microperfusion system for enhanced viability

    PubMed Central

    Rambani, Komal; Vukasinovic, Jelena; Glezer, Ari; Potter, Steve M.

    2009-01-01

    Brain slice preparations are well-established models for a wide spectrum of in vitro investigations in the neuroscience discipline. However, these investigations are limited to acute preparations or thin organotypic culture preparations due to the lack of a successful method that allows culturing of thick organotypic brain slices. Thick brain slice cultures suffer necrosis due to ischemia deep in the tissue resulting from a destroyed circulatory system and subsequent diffusion-limited supply of nutrients and oxygen. Although thin organotypic brain slice cultures can be successfully cultured using a well established roller tube method (a monolayer organotypic culture) (Gahwiler B H, 1981) or a membrane insert method (up to 1–4 cell layers, <150μm)(Stoppini L et al., 1991), these methods fail to support thick tissue preparations. A few perfusion methods (using submerged or interface/microfluidic chambers) have been reported to enhance the longevity (up to few hours) of acute slice preparations (up to 600μm thick) (Hass H L et al., 1979; Nicoll R A and Alger B E, 1981; Passeraub P A et al., 2003). Here, we report a unique interstitial microfluidic perfusion technique to culture thick (700μm) organotypic brain slices. The design of the custom-made micro-perfusion chamber facilitates laminar, interstitial perfusion of oxygenated nutrient medium throughout the tissue thickness with concomitant removal of depleted medium and catabolites. We examined the utility of this perfusion method to enhance the viability of the thick organotypic brain slice cultures after 2 days and 5 days in vitro (DIV). We investigated the range of amenable flow rates that enhance the viability of 700μm thick organotypic brain slices compared to the unperfused control cultures. Our perfusion method allows up to 84.6% viability (P<0.01) and up to 700μm thickness, even after 5 DIV. Our results also confirm that these cultures are functionally active and have their in vivo cytoarchitecture

  10. LONGEVITY AND VIABILITY OF Taenia solium EGGS IN THE DIGESTIVE SYSTEM OF THE BEETLE Ammophorus rubripes

    PubMed Central

    Gomez-Puerta, Luis Antonio; Lopez-Urbina, Maria Teresa; Garcia, Hector Hugo; Gonzalez, Armando Emiliano

    2015-01-01

    The present study evaluated the capacity of Ammophorus rubripes beetles to carry Taenia solium eggs, in terms of duration and viability of eggs in their digestive system. One hundred beetles were distributed into five polyethylene boxes, and then they were infected with T. solium eggs. Gravid proglottids of T. solium were crushed and then mixed with cattle feces. One gram of this mixture was placed in each box for 24 hours, after which each group of beetles was transferred into a new clean box. Then, five beetles were dissected every three days. Time was strongly associated with viability (r=0.89; P<0.001) and the calculated time to cero viability is 36 days. The eggs in the intestinal system of each beetle were counted and tested for viability. Taenia solium eggs were present in the beetle’s digestive system for up to 39 days (13th sampling day out of 20), gradually reducing in numbers and viability, which was 0 on day 36 post-infection. Egg viability was around 40% up to day 24 post-infection, with a median number of eggs of 11 per beetle at this time. Dung beetles may potentially contribute towards dispersing T. solium eggs in endemic areas. PMID:24728368

  11. Longevity and viability of Taenia solium eggs in the digestive system of the beetle Ammophorus rubripes.

    PubMed

    Gomez-Puerta, Luis Antonio; Lopez-Urbina, Maria Teresa; Garcia, Hector Hugo; Gonzalez, Armando Emiliano

    2014-03-01

    The present study evaluated the capacity of Ammophorus rubripes beetles to carry Taenia solium eggs, in terms of duration and viability of eggs in their digestive system. One hundred beetles were distributed into five polyethylene boxes, and then they were infected with T. solium eggs. Gravid proglottids of T. solium were crushed and then mixed with cattle feces. One gram of this mixture was placed in each box for 24 hours, after which each group of beetles was transferred into a new clean box. Then, five beetles were dissected every three days. Time was strongly associated with viability (r=0.89; P<0.001) and the calculated time to cero viability is 36 days. The eggs in the intestinal system of each beetle were counted and tested for viability. Taenia solium eggs were present in the beetle's digestive system for up to 39 days (13th sampling day out of 20), gradually reducing in numbers and viability, which was 0 on day 36 post-infection. Egg viability was around 40% up to day 24 post-infection, with a median number of eggs of 11 per beetle at this time. Dung beetles may potentially contribute towards dispersing T. solium eggs in endemic areas.

  12. Short range radio locator system

    DOEpatents

    McEwan, Thomas E.

    1996-01-01

    A radio location system comprises a wireless transmitter that outputs two megahertz period bursts of two gigahertz radar carrier signals. A receiver system determines the position of the transmitter by the relative arrival of the radar bursts at several component receivers set up to have a favorable geometry and each one having a known location. One receiver provides a synchronizing gating pulse to itself and all the other receivers to sample the ether for the radar pulse. The rate of the synchronizing gating pulse is slightly offset from the rate of the radar bursts themselves, so that each sample collects one finely-detailed piece of information about the time-of-flight of the radar pulse to each receiver each pulse period. Thousands of sequential pulse periods provide corresponding thousand of pieces of information about the time-of-flight of the radar pulse to each receiver, in expanded, not real time. Therefore the signal processing can be done with relatively low-frequency, inexpensive components. A conventional microcomputer is then used to find the position of the transmitter by geometric triangulation based on the relative time-of-flight information.

  13. Short range radio locator system

    DOEpatents

    McEwan, T.E.

    1996-12-31

    A radio location system comprises a wireless transmitter that outputs two megahertz period bursts of two gigahertz radar carrier signals. A receiver system determines the position of the transmitter by the relative arrival of the radar bursts at several component receivers set up to have a favorable geometry and each one having a known location. One receiver provides a synchronizing gating pulse to itself and all the other receivers. The rate of the synchronizing gating pulse is slightly offset from the rate of the radar bursts themselves, so that each sample collects one finely-detailed piece of information about the time-of-flight of the radar pulse to each receiver each pulse period. Thousands of sequential pulse periods provide corresponding thousand of pieces of information about the time-of-flight of the radar pulse to each receiver, in expanded, not real time. Therefore the signal processing can be done with relatively low-frequency, inexpensive components. A conventional microcomputer is then used to find the position of the transmitter by geometric triangulation based on the relative time-of-flight information. 5 figs.

  14. Comparison of five incubation systems for rat liver slices using functional and viability parameters.

    PubMed

    Olinga, P; Groen, K; Hof, I H; De Kanter, R; Koster, H J; Leeman, W R; Rutten, A A; Van Twillert, K; Groothuis, G M

    1997-10-01

    Precision-cut liver slices are presently used for various research objects, e.g. to study metabolism, transport, and toxicity of xenobiotics. Various incubation systems are presently employed, but a systematic comparison between these incubation systems with respect to preservation of slice function has not been performed yet. Therefore, we started a comparative study to evaluate five of these systems: the shaken flask (an Erlenmeyer in a shaking water bath), the stirred-well (24-well culture plate equipped with grids and magnetic stirrers), rocker platform (6-well culture plate with Netwell insert rocked on a platform), the roller system (dynamic organ culture rolled on an insert in a glass vial), and the 6-well shaker (6-well culture plate in a shaking water bath). The liver slices were incubated in these incubation systems for 0.5, 1.5, and 24.5 h and subsequently subjected to viability and metabolic function tests. The viability of the incubated liver slices was evaluated by: potassium content, MTT assay, energy charge, histomorphology, and LDH leakage. Their metabolic functions were studied by determination of the metabolism of lidocaine, testosterone, and antipyrine. Up to 1.5 h of incubation all five incubation systems gave similar results with respect to viability and metabolic function of the liver slices. However, after 24 h, the shaken flask, the rocker platform, and the 6-well shaker incubation systems appeared to be superior to the stirred well and the roller incubation systems.

  15. Optical range and range rate estimation for teleoperator systems

    NASA Technical Reports Server (NTRS)

    Shields, N. L., Jr.; Kirkpatrick, M., III; Malone, T. B.; Huggins, C. T.

    1974-01-01

    Range and range rate are crucial parameters which must be available to the operator during remote controlled orbital docking operations. A method was developed for the estimation of both these parameters using an aided television system. An experiment was performed to determine the human operator's capability to measure displayed image size using a fixed reticle or movable cursor as the television aid. The movable cursor was found to yield mean image size estimation errors on the order of 2.3 per cent of the correct value. This error rate was significantly lower than that for the fixed reticle. Performance using the movable cursor was found to be less sensitive to signal-to-noise ratio variation than was that for the fixed reticle. The mean image size estimation errors for the movable cursor correspond to an error of approximately 2.25 per cent in range suggesting that the system has some merit. Determining the accuracy of range rate estimation using a rate controlled cursor will require further experimentation.

  16. Optical range and range rate estimation for teleoperator systems

    NASA Technical Reports Server (NTRS)

    Shields, N. L., Jr.; Kirkpatrick, M., III; Malone, T. B.; Huggins, C. T.

    1974-01-01

    Range and range rate are crucial parameters which must be available to the operator during remote controlled orbital docking operations. A method was developed for the estimation of both these parameters using an aided television system. An experiment was performed to determine the human operator's capability to measure displayed image size using a fixed reticle or movable cursor as the television aid. The movable cursor was found to yield mean image size estimation errors on the order of 2.3 per cent of the correct value. This error rate was significantly lower than that for the fixed reticle. Performance using the movable cursor was found to be less sensitive to signal-to-noise ratio variation than was that for the fixed reticle. The mean image size estimation errors for the movable cursor correspond to an error of approximately 2.25 per cent in range suggesting that the system has some merit. Determining the accuracy of range rate estimation using a rate controlled cursor will require further experimentation.

  17. The xCELLigence system for real-time and label-free monitoring of cell viability.

    PubMed

    Ke, Ning; Wang, Xiaobo; Xu, Xiao; Abassi, Yama A

    2011-01-01

    We describe here the use of the xCELLigence system for label-free and real-time monitoring of cell -viability. The xCELLigence system uses specially designed microtiter plates containing interdigitated gold microelectrodes to noninvasively monitor the viability of cultured cells using electrical impedance as the readout. The continuous monitoring of cell viability by the xCELLigence system makes it possible to distinguish between different perturbations of cell viability, such as senescence, cell toxicity (cell death), and reduced proliferation (cell cycle arrest). In addition, the time resolution of the xCELLigence system allows for the determination of optimal time points to perform standard cell viability assays as well as other end-point assays to understand the mode of action. We have used the WST-1 assay (end-point viability readout), the cell index determination (continuous monitoring of viability by xCELLigence), and the DNA fragmentation assay (end-point apoptosis assay) to systematically examine cytotoxic effects triggered by two cytotoxic compounds with different cell-killing kinetics. Good correlation was observed for viability readouts between WST-1 and cell index. The significance of time resolution by xCELLigence readout is exemplified by its ability to pinpoint the optimal time points for conducting end point viability and apoptosis assays.

  18. CO2 laser ranging systems study

    NASA Technical Reports Server (NTRS)

    Filippi, C. A.

    1975-01-01

    The conceptual design and error performance of a CO2 laser ranging system are analyzed. Ranging signal and subsystem processing alternatives are identified, and their comprehensive evaluation yields preferred candidate solutions which are analyzed to derive range and range rate error contributions. The performance results are presented in the form of extensive tables and figures which identify the ranging accuracy compromises as a function of the key system design parameters and subsystem performance indexes. The ranging errors obtained are noted to be within the high accuracy requirements of existing NASA/GSFC missions with a proper system design.

  19. Fiber optic light-scattering measurement system for evaluation of embryo viability: model experiment

    NASA Astrophysics Data System (ADS)

    Itoh, Harumi; Arai, Tsunenori; Kikuchi, Makoto

    1996-05-01

    We evaluated the particle density detectability and particle size detectivity of our fiber-optic light-scattering measurement system. In order to prevent the multiple pregnancy on current in vitro fertilization-embryo transfer, we have aimed to develop a new quantitative and non- invasive method to select a single viable human embryo. We employed the measurement of mitochondria localization in an embryo, which may have the correlation with development ability. We applied the angular distribution measurement of the light-scattering intensity from the embryo to obtain the information originated from the mitochondria. The latex spheres with a diameter of 1.0 micrometers were used to simulate the scattering intensity of the mitochondria. The measurement probes of our system consisted of two fibers for illumination and sensing. They were arranged at a right angle to a microscope optical axis to measure the angular distribution of the light-scattering intensity. We observed that the light-scattering intensity increased monotonically in the range from 106 to 1010 particles per ml. Since the mitochondria density in a human embryo corresponded to 2.5 X 107 per ml in the measurement chamber, we may measure the mitochondria density in the human embryo. The angular dependence of light-scattering intensity changed with the sphere diameters. This result showed the possibility of the selective measurement of the mitochondria density in the embryo in spite of the presence of the other cell organelle. We think that our light-scattering measurement system might be applicable to the evaluation method for the embryo viability.

  20. Assessing the viability of `over-the-loop' real-time short-to-medium range ensemble streamflow forecasts

    NASA Astrophysics Data System (ADS)

    Wood, A. W.; Clark, E.; Mendoza, P. A.; Nijssen, B.; Newman, A. J.; Clark, M. P.; Arnold, J.; Nowak, K. C.

    2016-12-01

    Many if not most national operational short-to-medium range streamflow prediction systems rely on a forecaster-in-the-loop approach in which some parts of the forecast workflow are automated, but others require the hands-on-effort of an experienced human forecaster. This approach evolved out of the need to correct for deficiencies in the models and datasets that were available for forecasting, and often leads to skillful predictions despite the use of relatively simple, conceptual models. On the other hand, the process is not reproducible, which limits opportunities to assess and incorporate process variations, and the effort required to make forecasts in this way is an obstacle to expanding forecast services - e.g., though adding new forecast locations or more frequent forecast updates, running more complex models, or producing forecast ensembles and hindcasts that can support verification. In the last decade, the hydrologic forecasting community has begun to develop more centralized, `over-the-loop' systems. The quality of these new forecast products will depend on their ability to leverage research in areas including earth system modeling, parameter estimation, data assimilation, statistical post-processing, weather and climate prediction, verification, and uncertainty estimation through the use of ensembles. Currently, the operational streamflow forecasting and water management communities have little experience with the strengths and weaknesses of over-the-loop approaches, even as the systems are being rolled out in major operational forecasting centers. There is thus a need both to evaluate these forecasting advances and to demonstrate their potential in a public arena, raising awareness in forecast user communities and development programs alike. To address this need, the National Center for Atmospheric Research is collaborating with the University of Washington, the Bureau of Reclamation and the US Army Corps of Engineers, using the NCAR 'System for

  1. Video Target Tracking and Ranging System

    NASA Technical Reports Server (NTRS)

    Freedman, L. A.

    1983-01-01

    Proposed target tracking and ranging system uses two automatic video target trackers to keep two TV cameras trained on object being tracked. Microcomputer calculates range and range-rate information by triangulation. Input data for calculation are position coordinates of two cameras and pan and tilt aiming angles of two cameras. System is useful for target ranging at distances up to about 1,000 feet (300 m) in such applications as vehicle collision avoidance, traffic monitoring and surveillance. Also substitutes for short-range radar in situations where radar signal can not be tolerated.

  2. FSL Constructs: A Simple Method for Modifying Cell/Virion Surfaces with a Range of Biological Markers Without Affecting their Viability

    PubMed Central

    Blake, Deborah A.; Bovin, Nicolai V.; Bess, Dan; Henry, Stephen M.

    2011-01-01

    The ability to modify/visualize biological surfaces, and then study the modified cell/virion in a range of in vitro and in vivo environments is essential to gaining further insight into the function of specific molecules or the entire entity. Studies of biological surface modification are generally limited to genetic engineering of the organism or the covalent attachment of chemical moieties to the cell surface1,2. However these traditional techniques expose the cell to chemical reactants, or they require significant manipulation to achieve the desired outcome, making them cumbersome, and they may also inadvertently affect the viability/functionality of the modified cell. A simple method to harmlessly modify the surface of cells is required. Recently a new technology, KODE Technology has introduced a range of novel constructs consisting of three components: a functional head group (F), a spacer (S) and a lipid tail (L) and are known as Function-Spacer-Lipid or FSL constructs3. The spacer (S) is selected to provide a construct that is dispersible in water, yet will spontaneously and stably incorporate into a membrane. FSL construct functional moieties (F) so far include a range of saccharides including blood group-related determinants, sialic acids, hyaluronan polysaccharides, fluorophores, biotin, radiolabels, and a range of peptides3-12. FSL constructs have been used in modifying embryos, spermatozoa, zebrafish, epithelial/endometrial cells, red blood cells, and virions to create quality controls systems and diagnostic panels, to modify cell adhesion/ interaction/ separation/ immobilization, and for in vitro and in vivo imaging of cells/virions3-12. The process of modifying cells/virions is generic and extremely simple. The most common procedure is incubation of cells (in lipid free media) with a solution for FSL constructs for 1-2 hours at 37°C4-10. During the incubation the FSL constructs spontaneously incorporate into the membrane, and the process is complete

  3. Laser Doppler And Range Systems For Spacecraft

    NASA Technical Reports Server (NTRS)

    Kinman, P. W.; Gagliardi, R. M.

    1990-01-01

    Report discusses two types of proposed laser systems containing active transponders measuring distance (range) and line-of-sight velocity (via Doppler effect) between deep space vehicle and earth-orbiting satellite. Laser system offers diffraction advantage over microwave system. Delivers comparable power to distant receiver while using smaller transmitting and receiving antennas and less-powerful transmitter. Less subject to phase scintillations caused by passage through such inhomogeneous media as solar corona. One type of system called "incoherent" because range and Doppler measurements do not require coherence with laser carrier signals. Other type of system called "coherent" because successful operation requires coherent tracking of laser signals.

  4. Programmable near-infrared ranging system

    DOEpatents

    Everett, Jr., Hobart R.

    1989-01-01

    A high angular resolution ranging system particularly suitable for indoor plications involving mobile robot navigation and collision avoidance uses a programmable array of light emitters that can be sequentially incremented by a microprocessor. A plurality of adjustable level threshold detectors are used in an optical receiver for detecting the threshold level of the light echoes produced when light emitted from one or more of the emitters is reflected by a target or object in the scan path of the ranging system.

  5. Preserving viability of Lactobacillus rhamnosus GG in vitro and in vivo by a new encapsulation system

    PubMed Central

    Li, Ran; Zhang, Yufeng; Polk, D. Brent; Tomasula, Peggy M.; Yan, Fang; Liu, LinShu

    2016-01-01

    Probiotics have shown beneficial effects on health and prevention of diseases in humans. However, a concern for application of probiotics is the loss of viability during storage and gastrointestinal transit. The aim of this study was to develop an encapsulation system to preserve viability of probiotics when they are administrated orally and apply Lactobacillus rhamnosus GG (LGG) as a probiotic model to evaluate the effectiveness of this approach using in vitro and in vivo experiments. LGG was encapsulated in hydrogel beads prepared using pectin, a food grade polysaccharide, glucose, and calcium chloride, and lyophilized by freeze-drying. Encapsulated LGG was cultured in vitro under the condition that mimicked the physiological environment of the human gastrointestinal tract. Compared to non-encapsulated LGG, encapsulation increased tolerance of LGG in the acid condition, protected LGG from protease digestion, and improved shelf time when stored at the ambient condition, in regard of survivability and production of p40, a known LGG-derived protein involved in LGG’s beneficial effects on intestinal homeostasis. To evaluate the effects of encapsulation on p40 production in vivo and prevention of intestinal inflammation by LGG, mice were gavaged with LGG containing beads and treated with dextran sulphate sodium (DSS) to induce intestinal injury and colitis. Compared to non-encapsulated LGG, encapsulated LGG enhanced more p40 production in mice, and exerted higher levels of effects on prevention of DSS-induced colonic injury and colitis and suppression of pro-inflammatory cytokine production. These data indicated that the encapsulation system developed in this study preserves viability of LGG in vitro and in vivo, leading to longer shelf time and enhancing the functions of LGG in the gastrointestinal tract. Thus, this encapsulation approach may have the potential application for improving efficacy of probiotics. PMID:27063422

  6. Preserving viability of Lactobacillus rhamnosus GG in vitro and in vivo by a new encapsulation system.

    PubMed

    Li, Ran; Zhang, Yufeng; Polk, D Brent; Tomasula, Peggy M; Yan, Fang; Liu, LinShu

    2016-05-28

    Probiotics have shown beneficial effects on health and prevention of diseases in humans. However, a concern for application of probiotics is the loss of viability during storage and gastrointestinal transit. The aim of this study was to develop an encapsulation system to preserve viability of probiotics when they are administrated orally and apply Lactobacillus rhamnosus GG (LGG) as a probiotic model to evaluate the effectiveness of this approach using in vitro and in vivo experiments. LGG was encapsulated in hydrogel beads prepared using pectin, a food grade polysaccharide, glucose, and calcium chloride, and lyophilized by freeze-drying. Encapsulated LGG was cultured in vitro under the condition that mimicked the physiological environment of the human gastrointestinal tract. Compared to non-encapsulated LGG, encapsulation increased tolerance of LGG in the acid condition, protected LGG from protease digestion, and improved shelf time when stored at the ambient condition, in regard of survivability and production of p40, a known LGG-derived protein involved in LGG's beneficial effects on intestinal homeostasis. To evaluate the effects of encapsulation on p40 production in vivo and prevention of intestinal inflammation by LGG, mice were gavaged with LGG containing beads and treated with dextran sulphate sodium (DSS) to induce intestinal injury and colitis. Compared to non-encapsulated LGG, encapsulated LGG enhanced more p40 production in mice, and exerted higher levels of effects on prevention of DSS-induced colonic injury and colitis and suppression of pro-inflammatory cytokine production. These data indicated that the encapsulation system developed in this study preserves viability of LGG in vitro and in vivo, leading to longer shelf time and enhancing the functions of LGG in the gastrointestinal tract. Thus, this encapsulation approach may have the potential application for improving efficacy of probiotics.

  7. Trilateration range and range rate system. Volume 1: CDA system manual

    NASA Technical Reports Server (NTRS)

    1976-01-01

    This document is one of a series of manuals designed to provide the information required to operate and maintain the Command and Data Acquisition (CDA) equipment of the Trilateration Range and Range Rate (TRRR) System. Information pertaining to the equipment in the Trilateration Range and Range Rate System which is designed to interface with existing NASA equipment located at Wallops Island, Virginia is presented.

  8. Ultra High Mass Range Mass Spectrometer System

    DOEpatents

    Reilly, Peter T. A. [Knoxville, TN

    2005-12-06

    Applicant's present invention comprises mass spectrometer systems that operate in a mass range from 1 to 10.sup.16 DA. The mass spectrometer system comprising an inlet system comprising an aerodynamic lens system, a reverse jet being a gas flux generated in an annulus moving in a reverse direction and a multipole ion guide; a digital ion trap; and a thermal vaporization/ionization detector system. Applicant's present invention further comprises a quadrupole mass spectrometer system comprising an inlet system having a quadrupole mass filter and a thermal vaporization/ionization detector system. Applicant's present invention further comprises an inlet system for use with a mass spectrometer system, a method for slowing energetic particles using an inlet system. Applicant's present invention also comprises a detector device and a method for detecting high mass charged particles.

  9. System and Method for Scan Range Gating

    NASA Technical Reports Server (NTRS)

    Zuk, David M. (Inventor); Lindemann, Scott (Inventor)

    2017-01-01

    A system for scanning light to define a range gated signal includes a pulsed coherent light source that directs light into the atmosphere, a light gathering instrument that receives the light modified by atmospheric backscatter and transfers the light onto an image plane, a scanner that scans collimated light from the image plane to form a range gated signal from the light modified by atmospheric backscatter, a control circuit that coordinates timing of a scan rate of the scanner and a pulse rate of the pulsed coherent light source so that the range gated signal is formed according to a desired range gate, an optical device onto which an image of the range gated signal is scanned, and an interferometer to which the image of the range gated signal is directed by the optical device. The interferometer is configured to modify the image according to a desired analysis.

  10. Morphology and viability analysis of Streptomyces clavuligerus in industrial cultivation systems.

    PubMed

    Pinto, L S; Vieira, L M; Pons, M N; Fonseca, M M R; Menezes, J C

    2004-04-01

    The effects of varying inoculum age and production scale upon the morphology and viability of Streptomyces clavuligerus were studied by analyzing visible and fluorescent light images acquired throughout pilot-plant and pre-industrial scale fermentations. Changes in production scale reveal that in 5 m(3) fermentors, the maximum hyphal area obtained is double the value obtained in 0.5 m(3) fermentors. It is probably due to the higher shear stresses acting upon hyphae in the 0.5 m(3) fermentor caused by higher tip speeds observed in these. The morphological quantification based on elongation and branching rates allowed fermentations to be pattern classified into distinct physiological time zones namely elongation, branching, fragmentation, etc. The general pattern observed for fermentations inoculated with late exponential phase inocula was similar to the pattern of fermentations run with stationary phase inocula except that both the elongation and branching periods started earlier in the former case. Using the available staining technique and image acquisition system, the viability seemed to be generally high and constant throughout the time course of all the studied fermentations.

  11. Accurate prediction of pregnancy viability by means of a simple scoring system.

    PubMed

    Bottomley, Cecilia; Van Belle, Vanya; Kirk, Emma; Van Huffel, Sabine; Timmerman, Dirk; Bourne, Tom

    2013-01-01

    What is the performance of a simple scoring system to predict whether women will have an ongoing viable intrauterine pregnancy beyond the first trimester? A simple scoring system using demographic and initial ultrasound variables accurately predicts pregnancy viability beyond the first trimester with an area under the curve (AUC) in a receiver operating characteristic curve of 0.924 [95% confidence interval (CI) 0.900-0.947] on an independent test set. Individual demographic and ultrasound factors, such as maternal age, vaginal bleeding and gestational sac size, are strong predictors of miscarriage. Previous mathematical models have combined individual risk factors with reasonable performance. A simple scoring system derived from a mathematical model that can be easily implemented in clinical practice has not previously been described for the prediction of ongoing viability. This was a prospective observational study in a single early pregnancy assessment centre during a 9-month period. A cohort of 1881 consecutive women undergoing transvaginal ultrasound scan at a gestational age <84 days were included. Women were excluded if the first trimester outcome was not known. Demographic features, symptoms and ultrasound variables were tested for their influence on ongoing viability. Logistic regression was used to determine the influence on first trimester viability from demographics and symptoms alone, ultrasound findings alone and then from all the variables combined. Each model was developed on a training data set, and a simple scoring system was derived from this. This scoring system was tested on an independent test data set. The final outcome based on a total of 1435 participants was an ongoing viable pregnancy in 885 (61.7%) and early pregnancy loss in 550 (38.3%) women. The scoring system using significant demographic variables alone (maternal age and amount of bleeding) to predict ongoing viability gave an AUC of 0.724 (95% CI = 0.692-0.756) in the training set

  12. Demonstration of high sensitivity laser ranging system

    NASA Technical Reports Server (NTRS)

    Millar, Pamela S.; Christian, Kent D.; Field, Christopher T.

    1994-01-01

    We report on a high sensitivity semiconductor laser ranging system developed for the Gravity and Magnetic Earth Surveyor (GAMES) for measuring variations in the planet's gravity field. The GAMES laser ranging instrument (LRI) consists of a pair of co-orbiting satellites, one which contains the laser transmitter and receiver and one with a passive retro-reflector mounted in an drag-stabilized housing. The LRI will range up to 200 km in space to the retro-reflector satellite. As the spacecraft pair pass over the spatial variations in the gravity field, they experience along-track accelerations which change their relative velocity. These time displaced velocity changes are sensed by the LRI with a resolution of 20-50 microns/sec. In addition, the pair may at any given time be drifting together or apart at a rate of up to 1 m/sec, introducing a Doppler shift into the ranging signals. An AlGaAs laser transmitter intensity modulated at 2 GHz and 10 MHz is used as fine and medium ranging channels. Range is measured by comparing phase difference between the transmit and received signals at each frequency. A separate laser modulated with a digital code, not reported in this paper, will be used for coarse ranging to unambiguously determine the distance up to 200 km.

  13. Global positioning system missile test range applications

    SciTech Connect

    Partridge, M.E.

    1986-06-01

    Using the Global Positioning System (GPS), a missile under test could transmit its own position, reducing radar tracking requirements while still providing three-dimensional position and velocity data with the required accuracy. This study investigated minimum package size requirements for GPS implementation on the SRAM II missile as part of the joint test assembly telemetry system. Reported GPS missile test range applications are reviewed. The two missile tracking system implementations considered are a complete GPS package onboard the missile and onboard frequency translator that retransmits the GPS satellite signals. Accuracy and operation of the two methods are compared. A functional description of the GPS is provided.

  14. Ultrasonic Ranging System With Increased Resolution

    NASA Technical Reports Server (NTRS)

    Meyer, William E.; Johnson, William G.

    1987-01-01

    Master-oscillator frequency increased. Ultrasonic range-measuring system with 0.1-in. resolution provides continuous digital display of four distance readings, each updated four times per second. Four rangefinder modules in system are modified versions of rangefinder used for automatic focusing in commercial series of cameras. Ultrasonic pulses emitted by system innocuous to both people and equipment. Provides economical solutions to such distance-measurement problems as posed by boats approaching docks, truck backing toward loading platform, runway-clearance readout for tail of airplane with high angle attack, or burglar alarm.

  15. Atmospheric refraction errors in laser ranging systems

    NASA Technical Reports Server (NTRS)

    Gardner, C. S.; Rowlett, J. R.

    1976-01-01

    The effects of horizontal refractivity gradients on the accuracy of laser ranging systems were investigated by ray tracing through three dimensional refractivity profiles. The profiles were generated by performing a multiple regression on measurements from seven or eight radiosondes, using a refractivity model which provided for both linear and quadratic variations in the horizontal direction. The range correction due to horizontal gradients was found to be an approximately sinusoidal function of azimuth having a minimum near 0 deg azimuth and a maximum near 180 deg azimuth. The peak to peak variation was approximately 5 centimeters at 10 deg elevation and decreased to less than 1 millimeter at 80 deg elevation.

  16. Evaluation of OMV ranging and docking systems

    NASA Astrophysics Data System (ADS)

    McDonald, M. W.

    1985-01-01

    The Orbital Maneuvering Vehicle (OMV) will serve as a shuttle-based or permanent space station-based vehicle designed to rendezvous and soft dock with various other free-flying space vehicles for purposes of inspection, support, and retrieval. This study is concerned primarily with the eventual need for the OMV to rendezvous and dock softly with the Edwin P. Hubble Space Telescope (ST). Utilizing the available capabilities of the large microwave anechoic chamber facility at Marshall Space Flight Center for simulating docking target vehicle motions in a free-space environment, a program is being devised for benchmark testing of rendezvous and docking sensor systems proposed for use on the OMV. A testing regimen suitable for evaluating the accuracy and tracking agility in sensing range, range rate, and angle information at close ranges (0 R 30m) has been developed.

  17. Viability of decision-making systems in human and animal groups.

    PubMed

    Sueur, Cédric

    2012-08-07

    Shared and unshared consensuses are present in both human and animal societies. To date, few studies have applied an evolutionary perspective to the viability of these systems. This study therefore aimed to assess if decision-making allows group members to satisfy all their needs and to survive, decision after decision, day after day. The novelty of this study is the inclusion of multiple decision-making events with varying conditions and the parameterization of the model based on data in macaques, bringing the model closer to ecologically reality. The activity budgets of group members in the model did not differ significantly from those observed in macaques, making the model robust and providing mechanistic insight. Three different decision-making systems were then tested: (1) One single leader, (2) Leading according to needs and (3) Voting process. Results show that when individuals have equal needs, all decision-making systems are viable. However, one single leader cannot impose its decision when the needs of other group members differ too much from its own needs. The leading according to needs system is always viable whatever the group heterogeneity. However, the individual with the highest body mass decides in the majority of cases. Finally, the voting process also appears to be viable, with a majority threshold that differs according to group size and to different individual needs. This study is the first clear prediction of the different types of consensus in animal groups used in various different conditions.

  18. Long range position and Orientation Tracking System

    SciTech Connect

    Armstrong, G.A.; Jansen, J.F.; Burks, B.L.

    1996-02-01

    The long range Position and Orientation Tracking System is an active triangulation-based system that is being developed to track a target to a resolution of 6.35 mm (0.25 in.) and 0.009{degrees}(32.4 arcseconds) over a range of 13.72 m (45 ft.). The system update rate is currently set at 20 Hz but can be increased to 100 Hz or more. The tracking is accomplished by sweeping two pairs of orthogonal line lasers over infrared (IR) sensors spaced with known geometry with respect to one another on the target (the target being a rigid body attached to either a remote vehicle or a remote manipulator arm). The synchronization and data acquisition electronics correlates the time that an IR sensor has been hit by one of the four lasers and the angle of the respective mirror at the time of the hit. This information is combined with the known geometry of the IR sensors on the target to determine position and orientation of the target. This method has the advantage of allowing the target to be momentarily lost due to occlusions and then reacquired without having to return the target to a known reference point. The system also contains a camera with operator controlled lighting in each pod that allows the target to be continuously viewed from either pod, assuming their are no occlusions.

  19. Development of the seafloor acoustic ranging system

    NASA Astrophysics Data System (ADS)

    Osada, Y.; Kido, M.; Fujimoto, H.

    2007-12-01

    We have developed a seafloor acoustic ranging system, which simulates an operation with the DONET (Development of Dense Ocean-floor Network System for Earthquake and Tsunami) cable, to monitor seafloor crustal movement. The seafloor acoustic ranging system was based on the precise acoustic transponder (PXP). We have a few problems for the improvement of the resolution. One thing is the variation of sound speed. Another is the bending of ray path. A PXP measures horizontal distances on the seafloor from the round trip travel times of acoustic pulses between pairs of PXP. The PXP was equipped with the pressure, temperature gauge and tilt-meter. The variation of sound speed in seawater has a direct effect on the measurement. Therefore we collect the data of temperature and pressure. But we don't collect the data of salinity because of less influence than temperature and pressure. Accordingly a ray path of acoustic wave tends to be bent upward in the deep sea due to the Snell's law. As the acoustic transducer of each PXPs held about 3.0m above the seafloor, the baseline is too long for altitude from the seafloor. In this year we carried out the experiment for the seafloor acoustic ranging system. We deployed two PXPs at about 750m spacing on Kumano-nada. The water depth is about 2050m. We collected the 660 data in this experiment during one day. The round trip travel time show the variation with peak-to-peak amplitude of about 0.03msec. It was confirmed to explain the majority in this change by the change in sound speed according to the temperature and pressure. This results shows the resolution of acoustic measurements is +/-2mm. Acknowledgement This study is supported by 'DONET' of Ministry of Education, Culture, Sports, Science and Technology.

  20. ROA's Real time GNSS network and its viability in Alertes-RIM system

    NASA Astrophysics Data System (ADS)

    Cibeira Urtiaga, Ángel; Gárate, Jorge; Mendoza, Leonor

    2015-04-01

    San Fernando Naval Observatory deployed a Geodetic Continuous GNSS network from the mid nineties. The most of the sites are located in the South of the Iberian Peninsula. Nowadays time series of several years for the most of these sites are available. This is the most risky region in the peninsula due to the confrontation of two tectonic plates, i.e. Euro-Asiatic and African Plates. The former confrontation generated several faults, origin of important earthquakes (e.g. the big earthquake of Lisbon in 1775, whose epicenter was located in the Azores-Gibraltar fault, where Euro-Asiatic and African plates collide). In order to prevent higher aftermaths, the San Fernando Naval Observatory with the University of Cádiz and the University Complutense of Madrid, started to develop an early warning system, based on the study of the P waves, with the result of a prototype known as Alertes system. In early 2014 an improvement of the Alertes-RIM system began, introducing the study of viability of using high frequency geodetic GNSS signals in real time and others, looking for an improvement in the time of response in the previous instants of an earthquake. This project is still on process of development.

  1. Potassium uptake system Trk2 is crucial for yeast cell viability during anhydrobiosis.

    PubMed

    Borovikova, Diana; Herynkova, Pavla; Rapoport, Alexander; Sychrova, Hana

    2014-01-01

    Yeasts grow at very different potassium concentrations, adapting their intracellular cation levels to changes in the external environment. Potassium homeostasis is maintained with the help of several transporters mediating the uptake and efflux of potassium with various affinities and mechanisms. In the model yeast Saccharomyces cerevisiae, two uptake systems, Trk1 and Trk2, are responsible for the accumulation of a relatively high intracellular potassium content (200-300 mM) and the efflux of surplus potassium is mediated by the Tok1 channel and active exporters Ena ATPase and Nha1 cation/proton antiporter. Using a series of deletion mutants, we studied the role of individual potassium transporters in yeast cell resistance to dehydration. The Trk2 transporter (whose role in S. cerevisiae physiology was not clear) is important for cell viability in the stationary phase of growth and, moreover, it plays a crucial role in the yeast survival of dehydration/rehydration treatments. Mutants lacking the TRK2 gene accumulated significantly lower amounts of potassium ions in the stationary culture growth phase, and these lower amounts correlated with decreased resistance to dehydration/rehydration stress. Our results showed Trk2 to be the major potassium uptake system in stationary cells, and potassium content to be a crucial parameter for desiccation survival.

  2. Comparison of the Copan eSwab System with an Agar Swab Transport System for Maintenance of Fastidious Anaerobic Bacterium Viability

    PubMed Central

    Citron, Diane M.; Leoncio, Eliza S.; Goldstein, Ellie J. C.

    2016-01-01

    We compared the eSwab system to a swab with an anaerobic transport semisolid agar system for their capacities to maintain the viability of 20 species of fastidious anaerobes inoculated on the bench and held at ambient or refrigerator temperature for 24 or 48 h. On average, both systems maintained similar viabilities among analogous groups of organisms at both temperatures, although there were quantitative differences among some species. PMID:26888906

  3. Comparison of the Copan eSwab System with an Agar Swab Transport System for Maintenance of Fastidious Anaerobic Bacterium Viability.

    PubMed

    Tyrrell, Kerin L; Citron, Diane M; Leoncio, Eliza S; Goldstein, Ellie J C

    2016-05-01

    We compared the eSwab system to a swab with an anaerobic transport semisolid agar system for their capacities to maintain the viability of 20 species of fastidious anaerobes inoculated on the bench and held at ambient or refrigerator temperature for 24 or 48 h. On average, both systems maintained similar viabilities among analogous groups of organisms at both temperatures, although there were quantitative differences among some species. Copyright © 2016 Tyrrell et al.

  4. Long Range Infrared Surveillance System (LRIRSS)

    NASA Astrophysics Data System (ADS)

    Garcia, Gregg W.

    1987-09-01

    The contract requirement for the LRIRSS program was to design, fabricate, test, and deliver infrared (IR) surveillance systems capable of target detection and recognition at extended ranges. Several significant technical advancements were made during the course of the program. The twenty three inch primary reflecting surface had to be of aluminum due to thermal and weight considerations. This was accomplished through the use of diamond point turned aluminum. The IR and laser receivers are active simultaneously; this has been achieved through the incorporation of a "chopping" mirror that time shares the main aperture between the FLIR and CO2 laser receivers. In addition, the laser had to be eye-safe at the transmitter exit aperture. The use of a single pulse Carbon Dioxide (CO2) laser has met the requirement, and is certified by the US Army Environmental Hygiene Agency in Study No. 25-42-0335-85. The major technical challenges have been met, as well as several minor difficulties that arose during the execution of the effort. All hardware has been delivered to the Government in accord with the contractual schedule. NOMENCLATURE CO2 Carbon Dioxide CPU Central Processing Unit FLIR Forward Looking Infrared FOV Field of View IFOV Instantaneous Field of View IR Infrared LRF Laser Rangefinder LRIRSS Long Range Infrared Surveillance System PCB Printed Circuit Board

  5. Services for Mentally Retarded Persons: The Viability of a Short-Term Residential Service Setting in Pennsylvania's System.

    ERIC Educational Resources Information Center

    Isett, Robert; Spreat, Scott

    1979-01-01

    The viability of a short-term residential facility for the mentally retarded was examined, using client discharge and developmental growth data. Discharge for the profoundly retarded was not achieved. Findings highlighted the restraints imposed on evaluating one component of a large service delivery system. (MH)

  6. Initiative for Future Agricultural Food Systems (IFAFS) From Farm to School: Improving Small Farm Viability and School Meals

    ERIC Educational Resources Information Center

    Kish, Stacy

    2008-01-01

    Improving the nutritional value of school meals is a growing priority among school systems across the United States. To assist in this effort, the USDA's Cooperative State Research, Education, and Extension Service (CSREES) funded a coalition, which developed a new program called "From Farm to School: Improving Small Farm Viability and School…

  7. Comparison of the Copan ESwab system with two Amies agar swab transport systems for maintenance of microorganism viability.

    PubMed

    Van Horn, Kenneth G; Audette, Carol D; Sebeck, Denise; Tucker, Kelly A

    2008-05-01

    Swab transport systems are used for a variety of specimen types and must maintain organism viability throughout the transport process. The Copan ESwab is a new nylon-flocked swab designed to optimize specimen collection and to minimize entrapment of the specimen. We used the quantitative elution method with recommended strains, as described in CLSI document M40-A, to evaluate the ESwab for maintenance of viability of aerobic and anaerobic microorganisms for 0, 6, 24, and 48 h during room temperature and refrigerated temperature storage. The Becton Dickinson CultureSwab MaxV swab and the Remel BactiSwab were used as comparators. The ESwab met CLSI acceptance criteria for all aerobic isolates stored at both temperatures and for all anaerobic isolates stored at refrigerated temperature. The ESwab also met CLSI criteria for four of five anaerobic strains at room temperature. Prevotella melaninogenica was not recovered after 24 or 48 h of room temperature storage with any of the three swab transport systems tested. Overall, the ESwab was equivalent to the Becton Dickinson CultureSwab MaxV swab in organism recovery but recovered more isolates than Remel BactiSwab.

  8. Ultrasonic ranging and data telemetry system

    DOEpatents

    Brashear, Hugh R.; Blair, Michael S.; Phelps, James E.; Bauer, Martin L.; Nowlin, Charles H.

    1990-01-01

    An ultrasonic ranging and data telemetry system determines a surveyor's position and automatically links it with other simultaneously taken survey data. An ultrasonic and radio frequency (rf) transmitter are carried by the surveyor in a backpack. The surveyor's position is determined by calculations that use the measured transmission times of an airborne ultrasonic pulse transmitted from the backpack to two or more prepositioned ultrasonic transceivers. Once a second, rf communications are used both to synchronize the ultrasonic pulse transmission-time measurements and to transmit other simultaneously taken survey data. The rf communications are interpreted by a portable receiver and microcomputer which are brought to the property site. A video display attached to the computer provides real-time visual monitoring of the survey progress and site coverage.

  9. The Potential of Energy Storage Systems with Respect to Generation Adequacy and Economic Viability

    NASA Astrophysics Data System (ADS)

    Bradbury, Kyle Joseph

    Intermittent energy resources, including wind and solar power, continue to be rapidly added to the generation fleet domestically and abroad. The variable power of these resources introduces new levels of stochasticity into electric interconnections that must be continuously balanced in order to maintain system reliability. Energy storage systems (ESSs) offer one potential option to compensate for the intermittency of renewables. ESSs for long-term storage (1-hour or greater), aside from a few pumped hydroelectric installations, are not presently in widespread use in the U.S. The deployment of ESSs would be most likely driven by either the potential for a strong internal rate of return (IRR) on investment and through significant benefits to system reliability that independent system operators (ISOs) could incentivize. To assess the potential of ESSs three objectives are addressed. (1) Evaluate the economic viability of energy storage for price arbitrage in real-time energy markets and determine system cost improvements for ESSs to become attractive investments. (2) Estimate the reliability impact of energy storage systems on the large-scale integration of intermittent generation. (3) Analyze the economic, environmental, and reliability tradeoffs associated with using energy storage in conjunction with stochastic generation. First, using real-time energy market price data from seven markets across the U.S. and the physical parameters of fourteen ESS technologies, the maximum potential IRR of each technology from price arbitrage was evaluated in each market, along with the optimal ESS system size. Additionally, the reductions in capital cost needed to achieve a 10% IRR were estimated for each ESS. The results indicate that the profit-maximizing size of an ESS is primarily determined by its technological characteristics (round-trip charge/discharge efficiency and self-discharge) and not market price volatility, which instead increases IRR. This analysis demonstrates

  10. Novel diffuse optics system for continuous tissue viability monitoring: extended recovery in vivo testing in a porcine flap model

    NASA Astrophysics Data System (ADS)

    Lee, Seung Yup; Pakela, Julia M.; Hedrick, Taylor L.; Vishwanath, Karthik; Helton, Michael C.; Chung, Yooree; Kolodziejski, Noah J.; Stapels, Christopher J.; McAdams, Daniel R.; Fernandez, Daniel E.; Christian, James F.; O'Reilly, Jameson; Farkas, Dana; Ward, Brent B.; Feinberg, Stephen E.; Mycek, Mary-Ann

    2017-02-01

    In reconstructive surgery, tissue perfusion/vessel patency is critical to the success of microvascular free tissue flaps. Early detection of flap failure secondary to compromise of vascular perfusion would significantly increase the chances of flap salvage. We have developed a compact, clinically-compatible monitoring system to enable automated, minimally-invasive, continuous, and quantitative assessment of flap viability/perfusion. We tested the system's continuous monitoring capability during extended non-recovery surgery using an in vivo porcine free flap model. Initial results indicated that the system could assess flap viability/perfusion in a quantitative and continuous manner. With proven performance, the compact form constructed with cost-effective components would make this system suitable for clinical translation.

  11. REDEX: The ranging equipment diagnostic expert system

    NASA Technical Reports Server (NTRS)

    Luczak, Edward C.; Gopalakrishnan, K.; Zillig, David J.

    1989-01-01

    REDEX, an advanced prototype expert system that diagnoses hardware failures in the Ranging Equipment (RE) at NASA's Ground Network tracking stations is described. REDEX will help the RE technician identify faulty circuit cards or modules that must be replaced, and thereby reduce troubleshooting time. It features a highly graphical user interface that uses color block diagrams and layout diagrams to illustrate the location of a fault. A semantic network knowledge representation technique was used to model the design structure of the RE. A catalog of generic troubleshooting rules was compiled to represent heuristics that are applied in diagnosing electronic equipment. Specific troubleshooting rules were identified to represent additional diagnostic knowledge that is unique to the RE. Over 50 generic and 250 specific troubleshooting rules have been derived. REDEX is implemented in Prolog on an IBM PC AT-compatible workstation. Block diagram graphics displays are color-coded to identify signals that have been monitored or inferred to have nominal values, signals that are out of tolerance, and circuit cards and functions that are diagnosed as faulty. A hypertext-like scheme is used to allow the user to easily navigate through the space of diagrams and tables. Over 50 graphic and tabular displays have been implemented. REDEX is currently being evaluated in a stand-alone mode using simulated RE fault scenarios. It will soon be interfaced to the RE and tested in an online environment. When completed and fielded, REDEX will be a concrete example of the application of expert systems technology to the problem of improving performance and reducing the lifecycle costs of operating NASA's communications networks in the 1990's.

  12. REDEX - The ranging equipment diagnostic expert system

    NASA Technical Reports Server (NTRS)

    Luczak, Edward C.; Gopalakrishnan, K.; Zillig, David J.

    1989-01-01

    REDEX, an advanced prototype expert system that diagnoses hardware failures in the Ranging Equipment (RE) at NASA's Ground Network tracking stations is described. REDEX will help the RE technician identify faulty circuit cards or modules that must be replaced, and thereby reduce troubleshooting time. It features a highly graphical user interface that uses color block diagrams and layout diagrams to illustrate the location of a fault. A semantic network knowledge representation technique was used to model the design structure of the RE. A catalog of generic troubleshooting rules was compiled to represent heuristics that are applied in diagnosing electronic equipment. Specific troubleshooting rules were identified to represent additional diagnostic knowledge that is unique to the RE. Over 50 generic and 250 specific troubleshooting rules have been derived. REDEX is implemented in Prolog on an IBM PC AT-compatible workstation. Block diagram graphics displays are color-coded to identify signals that have been monitored or inferred to have nominal values, signals that are out of tolerance, and circuit cards and functions that are diagnosed as faulty. A hypertext-like scheme is used to allow the user to easily navigate through the space of diagrams and tables. Over 50 graphic and tabular displays have been implemented. REDEX is currently being evaluated in a stand-alone mode using simulated RE fault scenarios. It will soon be interfaced to the RE and tested in an online environment. When completed and fielded, REDEX will be a concrete example of the application of expert systems technology to the problem of improving performance and reducing the lifecycle costs of operating NASA's communications networks in the 1990s.

  13. GPS (Global Positioning System) Range Applications Study.

    DTIC Science & Technology

    1982-12-31

    Global Positioning System ( GPS ) as a source of Time i. Space Position ...THE ANALYTIC SCIENCES CORPORATION 2. GPS OVERVIEW This chapter provides a short, general introduction to the Global Positioning System ( GPS ) and...chapters. 2.1 SYSTEM OPERATION The NAVSTAR Global Positioning System ( GPS ) is a space- based radio navigation system designed to provide users with

  14. Laser System for Precise, Unambiguous Range Measurements

    NASA Technical Reports Server (NTRS)

    Dubovitsky, Serge; Lay, Oliver

    2005-01-01

    The Modulation Sideband Technology for Absolute Range (MSTAR) architecture is the basis of design of a proposed laser-based heterodyne interferometer that could measure a range (distance) as great as 100 km with a precision and resolution of the order of 1 nm. Simple optical interferometers can measure changes in range with nanometer resolution, but cannot measure range itself because interference is subject to the well-known integer-multiple-of-2 -radians phase ambiguity, which amounts to a range ambiguity of the order of 1 m at typical laser wavelengths. Existing rangefinders have a resolution of the order of 10 m and are therefore unable to resolve the ambiguity. The proposed MSTAR architecture bridges the gap, enabling nanometer resolution with an ambiguity range that can be extended to arbitrarily large distances. The MSTAR architecture combines the principle of the heterodyne interferometer with the principle of extending the ambiguity range of an interferometer by using light of two wavelengths. The use of two wavelengths for this purpose is well established in optical metrology, radar, and sonar. However, unlike in traditional two-color laser interferometry, light of two wavelengths would not be generated by two lasers. Instead, multiple wavelengths would be generated as sidebands of phase modulation of the light from a single frequency- stabilized laser. The phase modulation would be effected by applying sinusoidal signals of suitable frequencies (typically tens of gigahertz) to high-speed electro-optical phase modulators. Intensity modulation can also be used

  15. Ranging/tracking system for proximity operations

    NASA Technical Reports Server (NTRS)

    Nilsen, P.; Udalov, S.

    1982-01-01

    The hardware development and testing phase of a hand held radar for the ranging and tracking for Shuttle proximity operations are considered. The radar is to measure range to a 3 sigma accuracy of 1 m (3.28 ft) to a maximum range of 1850 m (6000 ft) and velocity to a 3 sigma accuracy of 0.03 m/s (0.1 ft/s). Size and weight are similar to hand held radars, frequently seen in use by motorcycle police officers. Meeting these goals for a target in free space was very difficult to obtain in the testing program; however, at a range of approximately 700 m, the 3 sigma range error was found to be 0.96 m. It is felt that much of this error is due to clutter in the test environment. As an example of the velocity accuracy, at a range of 450 m, a 3 sigma velocity error of 0.02 m/s was measured. The principles of the radar and recommended changes to its design are given. Analyses performed in support of the design process, the actual circuit diagrams, and the software listing are included.

  16. Economic viability and critical influencing factors assessment of black water and grey water source-separation sanitation system.

    PubMed

    Thibodeau, C; Monette, F; Glaus, M; Laflamme, C B

    2011-01-01

    The black water and grey water source-separation sanitation system aims at efficient use of energy (biogas), water and nutrients but currently lacks evidence of economic viability to be considered a credible alternative to the conventional system. This study intends to demonstrate economic viability, identify main cost contributors and assess critical influencing factors. A technico-economic model was built based on a new neighbourhood in a Canadian context. Three implementation scales of source-separation system are defined: 500, 5,000 and 50,000 inhabitants. The results show that the source-separation system is 33% to 118% more costly than the conventional system, with the larger cost differential obtained by lower source-separation system implementation scales. A sensitivity analysis demonstrates that vacuum toilet flow reduction from 1.0 to 0.25 L/flush decreases source-separation system cost between 23 and 27%. It also shows that high resource costs can be beneficial or unfavourable to the source-separation system depending on whether the vacuum toilet flow is low or normal. Therefore, the future of this configuration of the source-separation system lies mainly in vacuum toilet flow reduction or the introduction of new efficient effluent volume reduction processes (e.g. reverse osmosis).

  17. SYSTEM FOR AND METHOD OF DETERMINING RANGE

    DOEpatents

    Horrell, M.W.; Sanders, E.R.

    1963-11-01

    A system and method for indicating a predetermined altitude of an object or aircraft is described. The device utilizes a pulse transmit-receive system wherein pulses of predetermined width are transmitted towards the ground and the reflected pulses received gating only pulses having a predetermined width. (AEC)

  18. Dual-range linearized transimpedance amplifier system

    DOEpatents

    Wessendorf, Kurt O.

    2010-11-02

    A transimpedance amplifier system is disclosed which simultaneously generates a low-gain output signal and a high-gain output signal from an input current signal using a single transimpedance amplifier having two different feedback loops with different amplification factors to generate two different output voltage signals. One of the feedback loops includes a resistor, and the other feedback loop includes another resistor in series with one or more diodes. The transimpedance amplifier system includes a signal linearizer to linearize one or both of the low- and high-gain output signals by scaling and adding the two output voltage signals from the transimpedance amplifier. The signal linearizer can be formed either as an analog device using one or two summing amplifiers, or alternately can be formed as a digital device using two analog-to-digital converters and a digital signal processor (e.g. a microprocessor or a computer).

  19. Cell viability assays: introduction.

    PubMed

    Stoddart, Martin J

    2011-01-01

    The measurement of cell viability plays a fundamental role in all forms of cell culture. Sometimes it is the main purpose of the experiment, such as in toxicity assays. Alternatively, cell viability can be used to -correlate cell behaviour to cell number, providing a more accurate picture of, for example, anabolic -activity. There are wide arrays of cell viability methods which range from the most routine trypan blue dye exclusion assay to highly complex analysis of individual cells, such as using RAMAN microscopy. The cost, speed, and complexity of equipment required will all play a role in determining the assay used. This chapter aims to provide an overview of many of the assays available today.

  20. Hyperspectral range imaging for transportation systems evaluation

    NASA Astrophysics Data System (ADS)

    Bridgelall, Raj; Rafert, J. B.; Atwood, Don; Tolliver, Denver D.

    2016-04-01

    Transportation agencies expend significant resources to inspect critical infrastructure such as roadways, railways, and pipelines. Regular inspections identify important defects and generate data to forecast maintenance needs. However, cost and practical limitations prevent the scaling of current inspection methods beyond relatively small portions of the network. Consequently, existing approaches fail to discover many high-risk defect formations. Remote sensing techniques offer the potential for more rapid and extensive non-destructive evaluations of the multimodal transportation infrastructure. However, optical occlusions and limitations in the spatial resolution of typical airborne and space-borne platforms limit their applicability. This research proposes hyperspectral image classification to isolate transportation infrastructure targets for high-resolution photogrammetric analysis. A plenoptic swarm of unmanned aircraft systems will capture images with centimeter-scale spatial resolution, large swaths, and polarization diversity. The light field solution will incorporate structure-from-motion techniques to reconstruct three-dimensional details of the isolated targets from sequences of two-dimensional images. A comparative analysis of existing low-power wireless communications standards suggests an application dependent tradeoff in selecting the best-suited link to coordinate swarming operations. This study further produced a taxonomy of specific roadway and railway defects, distress symptoms, and other anomalies that the proposed plenoptic swarm sensing system would identify and characterize to estimate risk levels.

  1. Microprocessor realizations of range and range-rate filters in radar systems

    NASA Technical Reports Server (NTRS)

    Fleischer, D.; Aronhime, P.

    1980-01-01

    This paper describes the implementation of digital radar range-rate filters on a microprocessor-based system. A range-rate filter processes a digitized noisy range signal to recover smoothed range data and its derivative, range rate. Two filter designs are implemented. Considerations aiding their efficient operation on an 8-bit microprocessor are discussed. The filters are subjected to a noisy range input signal of known variance, and the associated output signals are statistically analysed to determine noise-rejection characteristics. These results are compared to analytical predictions.

  2. The cybernetics of viability: an overview

    NASA Astrophysics Data System (ADS)

    Nechansky, Helmut

    2011-10-01

    A three-level approach to viability is developed, considering (1) living systems, (2) a niche, understood as the area within the reach of their actions, and (3) an environment. A systematic analysis of the interrelations between these levels shows that living systems emerge with matter/energy processing systems. These can add controller structures when producing excess energy. A three-sensor controller structure enables a living system to deal with unfavourable and scarce environments. Further evolution of these controller structures offers improved ways to act on niches. Maintaining niches in scarce environments can require technology or economy. So social systems emerge, which are understood as aggregates of living systems. Basic patterns of interactions within social systems are analysed. So the introduction of the notion of the niche into the discussion of viability allows us to explain phenomena ranging from properties of single living systems to societal organization.

  3. The viability of cells obtained using the Reamer-Irrigator-Aspirator system and in bone graft from the iliac crest.

    PubMed

    Uppal, H S; Peterson, B E; Misfeldt, M L; Della Rocca, G J; Volgas, D A; Murtha, Y M; Stannard, J P; Choma, T J; Crist, B D

    2013-09-01

    We hypothesised that cells obtained via a Reamer-Irrigator-Aspirator (RIA) system retain substantial osteogenic potential and are at least equivalent to graft harvested from the iliac crest. Graft was harvested using the RIA in 25 patients (mean age 37.6 years (18 to 68)) and from the iliac crest in 21 patients (mean age 44.6 years (24 to 78)), after which ≥ 1 g of bony particulate graft material was processed from each. Initial cell viability was assessed using Trypan blue exclusion, and initial fluorescence-activated cell sorting (FACS) analysis for cell lineage was performed. After culturing the cells, repeat FACS analysis for cell lineage was performed and enzyme-linked immunosorbent assay (ELISA) for osteocalcin, and Alizarin red staining to determine osteogenic potential. Cells obtained via RIA or from the iliac crest were viable and matured into mesenchymal stem cells, as shown by staining for the specific mesenchymal antigens CD90 and CD105. For samples from both RIA and the iliac crest there was a statistically significant increase in bone production (both p < 0.001), as demonstrated by osteocalcin production after induction. Medullary autograft cells harvested using RIA are viable and osteogenic. Cell viability and osteogenic potential were similar between bone grafts obtained from both the RIA system and the iliac crest.

  4. Design of high-precision ranging system for laser fuze

    NASA Astrophysics Data System (ADS)

    Chen, Shanshan; Zhang, He; Xu, Xiaobin

    2016-10-01

    According to the problem of the high-precision ranging in the circumferential scanning probe laser proximity fuze, a new type of pulsed laser ranging system has been designed. The laser transmitting module, laser receiving module and ranging processing module have been designed respectively. The factors affecting the ranging accuracy are discussed. And the method of improving the ranging accuracy is studied. The high-precision ranging system adopts the general high performance microprocessor C8051FXXX as the core. And the time interval measurement chip TDC-GP21 was used to implement the system. A PCB circuit board was processed to carry on the experiment. The results of the experiment prove that a centimeter level accuracy ranging system has been achieved. The works can offer reference for ranging system design of the circumferential scanning probe laser proximity fuze.

  5. Myocardial viability.

    PubMed Central

    Birnbaum, Y; Kloner, R A

    1996-01-01

    Left ventricular function is a major predictor of outcome in patients with coronary artery disease. Acute ischemia, postischemic dysfunction (stunning), myocardial hibernation, or a combination of these 3 are among the reversible forms of myocardial dysfunction. In myocardial stunning, dysfunction occurs despite normal myocardial perfusion, and function recovers spontaneously over time. In acute ischemia and hibernation, there is regional hypoperfusion. Function improves only after revascularization. Evidence of myocardial viability usually relies on the demonstration of uptake of various metabolic tracers, such as thallium (thallous chloride TI 201) or fludeoxyglucose F 18, by dysfunctional myocardium or by the demonstration of contractile reserve in a dysfunctional region. This can be shown as an augmentation of function during the infusion of various sympathomimetic agents. The response of ventricular segments to increasing doses of dobutamine may indicate the underlying mechanism of dysfunction. Stunned segments that have normal perfusion show dose-dependent augmentation of function. If perfusion is reduced as in hibernating myocardium, however, a biphasic response usually occurs: function improves at low doses of dobutamine, whereas higher doses may induce ischemia and, hence, dysfunction. But in patients with severely impaired perfusion, even low doses may cause ischemia. Myocardial regions with subendocardial infarction or diffuse scarring may also have augmented contractility during catecholamine infusion due to stimulation of the subepicardial layers. In these cases, augmentation of function after revascularization is not expected. Because the underlying mechanism, prognosis, and therapy may differ among these conditions, it is crucial to differentiate among dysfunctional myocardial segments that are nonviable and have no potential to regain function, hibernating or ischemic segments in which recovery of function occurs only after revascularization, and

  6. Mating system and early viability resistance to habitat fragmentation in a bird-pollinated eucalypt

    PubMed Central

    Breed, M F; Ottewell, K M; Gardner, M G; Marklund, M H K; Stead, M G; Harris, J B C; Lowe, A J

    2015-01-01

    Habitat fragmentation has been shown to disrupt ecosystem processes such as plant-pollinator mutualisms. Consequently, mating patterns in remnant tree populations are expected to shift towards increased inbreeding and reduced pollen diversity, with fitness consequences for future generations. However, mating patterns and phenotypic assessments of open-pollinated progeny have rarely been combined in a single study. Here, we collected seeds from 37 Eucalyptus incrassata trees from contrasting stand densities following recent clearance in a single South Australian population (intact woodland=12.6 trees ha−1; isolated pasture=1.7 trees ha−1; population area=10 km2). 649 progeny from these trees were genotyped at eight microsatellite loci. We estimated genetic diversity, spatial genetic structure, indirect contemporary pollen flow and mating patterns for adults older than the clearance events and open-pollinated progeny sired post-clearance. A proxy of early stage progeny viability was assessed in a common garden experiment. Density had no impact on mating patterns, adult and progeny genetic diversity or progeny growth, but was associated with increased mean pollen dispersal. Weak spatial genetic structure among adults suggests high historical gene flow. We observed preliminary evidence for inbreeding depression related to stress caused by fungal infection, but which was not associated with density. Higher observed heterozygosities in adults compared with progeny may relate to weak selection on progeny and lifetime-accumulated mortality of inbred adults. E. incrassata appears to be resistant to the negative mating pattern and fitness changes expected within fragmented landscapes. This pattern is likely explained by strong outcrossing and regular long-distance pollen flow. PMID:23188172

  7. Mating system and early viability resistance to habitat fragmentation in a bird-pollinated eucalypt.

    PubMed

    Breed, M F; Ottewell, K M; Gardner, M G; Marklund, M H K; Stead, M G; Harris, J B C; Lowe, A J

    2015-08-01

    Habitat fragmentation has been shown to disrupt ecosystem processes such as plant-pollinator mutualisms. Consequently, mating patterns in remnant tree populations are expected to shift towards increased inbreeding and reduced pollen diversity, with fitness consequences for future generations. However, mating patterns and phenotypic assessments of open-pollinated progeny have rarely been combined in a single study. Here, we collected seeds from 37 Eucalyptus incrassata trees from contrasting stand densities following recent clearance in a single South Australian population (intact woodland=12.6 trees ha(-1); isolated pasture=1.7 trees ha(-1); population area=10 km(2)). 649 progeny from these trees were genotyped at eight microsatellite loci. We estimated genetic diversity, spatial genetic structure, indirect contemporary pollen flow and mating patterns for adults older than the clearance events and open-pollinated progeny sired post-clearance. A proxy of early stage progeny viability was assessed in a common garden experiment. Density had no impact on mating patterns, adult and progeny genetic diversity or progeny growth, but was associated with increased mean pollen dispersal. Weak spatial genetic structure among adults suggests high historical gene flow. We observed preliminary evidence for inbreeding depression related to stress caused by fungal infection, but which was not associated with density. Higher observed heterozygosities in adults compared with progeny may relate to weak selection on progeny and lifetime-accumulated mortality of inbred adults. E. incrassata appears to be resistant to the negative mating pattern and fitness changes expected within fragmented landscapes. This pattern is likely explained by strong outcrossing and regular long-distance pollen flow.

  8. Challenges in miniaturized automotive long-range lidar system design

    NASA Astrophysics Data System (ADS)

    Fersch, Thomas; Weigel, Robert; Koelpin, Alexander

    2017-05-01

    This paper discusses the current technical limitations posed on endeavors to miniaturize lidar systems for use in automotive applications and how to possibly extend those limits. The focus is set on long-range scanning direct time of flight LiDAR systems using APD photodetectors. Miniaturization evokes severe problems in ensuring absolute laser safety while maintaining the systems' performance in terms of maximum range, signal-to-noise ratio, detection probability, pixel density, or frame rate. Based on hypothetical but realistic specifications for an exemplary system the complete lidar signal path is calculated. The maximum range of the system is used as a general performance indicator. It is determined with the minimum signal-to-noise ratio required to detect an object. Various system parameters are varied to find their impact on the system's range. The reduction of the laser's pulse width and the right choice for the transimpedance amplifier's amplification have shown to be practicable measures to double the system's range.

  9. Fiber optic light-scattering measurement system for evaluation of embryo viability: light-scattering characteristics from live mouse embryo

    NASA Astrophysics Data System (ADS)

    Itoh, Harumi; Arai, Tsunenori; Kikuchi, Makoto

    1997-06-01

    We measured angular distribution of the light scattering from live mouse embryo with 632.8nm in wavelength to evaluate the embryo viability. We aim to measure the mitochondrial density in human embryo which have relation to the embryo viability. We have constructed the light scattering measurement system to detect the mitochondrial density non-invasively. We have employed two optical fibers for the illumination and sensing to change the angle between these fibers. There were two dips on the scattering angular distribution from the embryo. These dips existed on 30 and 85 deg. We calculated the scattering angular pattern by Mie theory to fit the measured scattering estimated scattering size and density. The best fitting was obtained when the particle size and density were 0.9 micrometers and 1010 particles per ml, respectively. These values coincided with the approximated values of mitochondrial in the embryo. The measured light scattering may mainly originated from mitochondria in spite of the existence of the various scattering particles in the embryo. Since our simple scattering measurement may offer the mitochondrial density in the embryo, it might become the practical method of human embryo on in vitro fertilization-embryo transfer.

  10. Ranging and tracking system for proximity operations, phase 1

    NASA Technical Reports Server (NTRS)

    Udalov, S.; Nilsen, P. W.

    1979-01-01

    A study task is reported which is directed towards developing a conceptual design of a small, lightweight range and range rate radar sensor system to meet NASA's requirements for accurate short-range and velocity measurements in an orbital environment. Within the context of the requirements, the short range implies system operation at 0 m to 1850 m (6000 ft) and accurate implies a range measurement to within 1 sigma accuracy of 0.20 m (0.67 ft) and a range rate (velocity) measurement to within 1 sigma accuracy of 0.01 m/sec (0.033 ft/sec).

  11. Lightning threat warning system at the Tonopah Test Range

    SciTech Connect

    Smith, R

    1992-07-01

    This report documents the lightning threat warning system at the Tonopah Test Range and the technology it uses. The report outlines each of the system's individual components and the information each contributes.

  12. Issues of organizational cybernetics and viability beyond Beer's viable systems model

    NASA Astrophysics Data System (ADS)

    Nechansky, Helmut

    2013-11-01

    The paper starts summarizing the claims of Beer's viable systems model to identify five issues any viable organizations has to deal with in an unequivocal hierarchical structure of five interrelated systems. Then the evidence is introduced for additional issues and related viable structures of organizations, which deviate from Beer's model. These issues are: (1) the establishment and (2) evolution of an organization; (3) systems for independent top-down control (like "Six Sigma"); (4) systems for independent bottom-up correction of performance problems (like "Kaizen"), both working outside a hierarchical structure; (5) pull production systems ("Just in Time") and (6) systems for checks and balances of top-level power (like boards and shareholder meetings). Based on that an evolutionary approach to organizational cybernetics is outlined, addressing the establishment of organizations and possible courses of developments, including recent developments in quality and production engineering, as well as problems of setting and changing goal values determining organizational policies.

  13. The financial viability of an SOFC cogeneration system in single-family dwellings

    NASA Astrophysics Data System (ADS)

    Alanne, Kari; Saari, Arto; Ugursal, V. Ismet; Good, Joel

    In the near future, fuel cell-based residential micro-CHP systems will compete with traditional methods of energy supply. A micro-CHP system may be considered viable if its incremental capital cost compared to its competitors equals to cumulated savings during a given period of time. A simplified model is developed in this study to estimate the operation of a residential solid oxide fuel cell (SOFC) system. A comparative assessment of the SOFC system vis-à-vis heating systems based on gas, oil and electricity is conducted using the simplified model for a single-family house located in Ottawa and Vancouver. The energy consumption of the house is estimated using the HOT2000 building simulation program. A financial analysis is carried out to evaluate the sensitivity of the maximum allowable capital cost with respect to system sizing, acceptable payback period, energy price and the electricity buyback strategy of an energy utility. Based on the financial analysis, small (1-2 kW e) SOFC systems seem to be feasible in the considered case. The present study shows also that an SOFC system is especially an alternative to heating systems based on oil and electrical furnaces.

  14. Fault tolerant computing: A preamble for assuring viability of large computer systems

    NASA Technical Reports Server (NTRS)

    Lim, R. S.

    1977-01-01

    The need for fault-tolerant computing is addressed from the viewpoints of (1) why it is needed, (2) how to apply it in the current state of technology, and (3) what it means in the context of the Phoenix computer system and other related systems. To this end, the value of concurrent error detection and correction is described. User protection, program retry, and repair are among the factors considered. The technology of algebraic codes to protect memory systems and arithmetic codes to protect memory systems and arithmetic codes to protect arithmetic operations is discussed.

  15. The Financial Management System: A Pivotal Tool for Fiscal Viability. CDS Spotlight. ECAR Research Bulletin

    ERIC Educational Resources Information Center

    Lang, Leah; Pirani, Judith A.

    2014-01-01

    This spotlight focuses on data from the 2013 CDS to better understand how higher education institutions approach financial management systems. Information provided for this spotlight was derived from Module 8 of Core Data Service (CDS), which asked several questions regarding information systems and applications. Responses from 525 institutions…

  16. The Financial Management System: A Pivotal Tool for Fiscal Viability. CDS Spotlight. ECAR Research Bulletin

    ERIC Educational Resources Information Center

    Lang, Leah; Pirani, Judith A.

    2014-01-01

    This spotlight focuses on data from the 2013 CDS to better understand how higher education institutions approach financial management systems. Information provided for this spotlight was derived from Module 8 of Core Data Service (CDS), which asked several questions regarding information systems and applications. Responses from 525 institutions…

  17. Identification, Description, and Perceived Viability of K-12 Consolidated Catholic School Systems

    ERIC Educational Resources Information Center

    Britt, Kenith C.

    2013-01-01

    Catholic education has been in a state of substantial decline since 1965. In order to help sustain the ministry of Catholic schools, one approach that several dozen dioceses have embraced is the K-12 consolidated Catholic school system. This study investigated the organizational structures within consolidated school systems, factors that led to…

  18. Temperature inversion in long-range interacting systems.

    PubMed

    Teles, Tarcísio N; Gupta, Shamik; Di Cintio, Pierfrancesco; Casetti, Lapo

    2015-08-01

    Temperature inversions occur in nature, e.g., in the solar corona and in interstellar molecular clouds: Somewhat counterintuitively, denser parts of the system are colder than dilute ones. We propose a simple and appealing way to spontaneously generate temperature inversions in systems with long-range interactions, by preparing them in inhomogeneous thermal equilibrium states and then applying an impulsive perturbation. In similar situations, short-range systems would typically relax to another thermal equilibrium, with a uniform temperature profile. By contrast, in long-range systems, the interplay between wave-particle interaction and spatial inhomogeneity drives the system to nonequilibrium stationary states that generically exhibit temperature inversion. We demonstrate this mechanism in a simple mean-field model and in a two-dimensional self-gravitating system. Our work underlines the crucial role the range of interparticle interaction plays in determining the nature of steady states out of thermal equilibrium.

  19. A Novel Isolator-Based System Promotes Viability of Human Embryos during Laboratory Processing

    PubMed Central

    Hyslop, Louise; Prathalingam, Nilendran; Nowak, Lynne; Fenwick, Jeanette; Harbottle, Steve; Byerley, Samantha; Rhodes, John; Watson, Bruce; Henderson, Robin; Murdoch, Alison; Herbert, Mary

    2012-01-01

    In vitro fertilisation (IVF) and related technologies are arguably the most challenging of all cell culture applications. The starting material is a single cell from which one aims to produce an embryo capable of establishing a pregnancy eventually leading to a live birth. Laboratory processing during IVF treatment requires open manipulations of gametes and embryos, which typically involves exposure to ambient conditions. To reduce the risk of cellular stress, we have developed a totally enclosed system of interlinked isolator-based workstations designed to maintain oocytes and embryos in a physiological environment throughout the IVF process. Comparison of clinical and laboratory data before and after the introduction of the new system revealed that significantly more embryos developed to the blastocyst stage in the enclosed isolator-based system compared with conventional open-fronted laminar flow hoods. Moreover, blastocysts produced in the isolator-based system contained significantly more cells and their development was accelerated. Consistent with this, the introduction of the enclosed system was accompanied by a significant increase in the clinical pregnancy rate and in the proportion of embryos implanting following transfer to the uterus. The data indicate that protection from ambient conditions promotes improved development of human embryos. Importantly, we found that it was entirely feasible to conduct all IVF-related procedures in the isolator-based workstations. PMID:22393356

  20. Research and emulation of ranging in BPON system

    NASA Astrophysics Data System (ADS)

    Yang, Guangxiang; Tao, Dexin; He, Yan

    2005-12-01

    Ranging is one of the key technologies in Broadband Passive Optical Network based on the ATM (BPON) system. It is complex for software designers and difficult to test. In order to simplify the ranging procedure, enhance its efficiency, and find an appropriate method to verify it, a new ranging procedure that completely satisfies the requirements specified in ITU-T G.983.1 and one verifying method is proposed in this paper. A kind of ranging procedure without serial number (SN) searching function, called one-by-one ranging are developed under the condition of cold PON, cold Optical Network Termination (ONU). The ranging procedure includes the use of OLT and ONU flow charts respectively. By using the network emulation software OPNET, the BPON system is modeled and the ranging procedure is simulated. The emulation experimental results show that the presented ranging procedure can effectively eliminate the collision of burst mode signals between ONUs, which can be ranged one-by-one under the controlling of OLT, while also enhancing the ranging efficiency. As all of the message formats used in this research conform with the ITU-T G.983.1, the ranging procedure can meet the protocol specifications with good interoperability, and is very compatible with products of other manufacturer. According to the present study of ranging procedures, guidelines and principles are provided, Also some design difficulties are eliminated in the software design.

  1. Integrated laser/radar satellite ranging and tracking system

    NASA Technical Reports Server (NTRS)

    Hoge, F. E.

    1974-01-01

    A laser satellite ranging system that is mounted upon and integrated with a microwave tracking radar is reported. The 1-pulse/sec ruby laser transmitter is attached directly to the radar's elevation axis and radiates through a new opening in the radar's parabolic dish. The laser photomultiplier tube receiver utilizes the radar's existing 20-cm diam f/11 boresight telescope and observes through a similar symmetrically located opening in the dish. The laser system possesses separate ranging system electronics but shares the radar's timing, computer, and data handling/recording systems. The basic concept of the laser/radar is outlined together with a listing of the numerous advantages over present singular laser range-finding systems. The developmental laser hardware is described along with preliminary range-finding results and expectations.

  2. Analysis on short-range millimetre wave scattering imaging system

    NASA Astrophysics Data System (ADS)

    Zhu, Li; Li, Xing-Guo; Lou, Guo-Wei; Zhang, Chao

    2011-08-01

    A system for short-range millimetre wave(MMW) active imaging was developed, including transceiver antenna, scanning system, transceiver front-end, signal processing. A target within a few meters or even a few centimeters can be imaged. The overall structure of the imaging system and imaging method were researched. The short-range scattering imaging formula was derived from the spectral distribution shift view, which can simplify the method. Phase compensation factor was introduced to improve the imaging resolution. The relationship between the sampling frequency and scanning speed was analyzed to optimize the system parameters, which can improve image quality and system efficiency.

  3. Laser system range calculations and the Lambert W function.

    PubMed

    Steinvall, Ove

    2009-02-01

    The knowledge of range performance versus atmospheric transmission, often given by the visibility, is critical for the design, use, and prediction of laser and passive electro-optic systems. I present a solution of the ladar-lidar equation based on Lambert's W function. This solution will reveal the dependence of the maximum range on the system and target parameters for different atmospheric attenuations and will also allow us to take the signal statistics into account by studying the influence on the threshold signal-to-noise ratio. The method is also applicable to many range calculations for passive systems where the atmospheric loss can be approximated by an exponential term.

  4. Evaluation of the implementation of a quality system in a basic research laboratory: viability and impacts.

    PubMed

    Fraga, Hilda Carolina de Jesus Rios; Fukutani, Kiyoshi Ferreira; Celes, Fabiana Santana; Barral, Aldina Maria Prado; Oliveira, Camila Indiani de

    2012-01-01

    To evaluate the process of implementing a quality management system in a basic research laboratory of a public institution, particularly considering the feasibility and impacts of this improvement. This was a prospective and qualitative study. We employed the norm "NIT DICLA 035--Princípios das Boas Práticas de Laboratório (BPL)" and auxiliary documents of Organisation for Economic Co-operation and Development to complement the planning and implementation of a Quality System, in a basic research laboratory. In parallel, we used the PDCA tool to define the goals of each phase of the implementation process. This study enabled the laboratory to comply with the NIT DICLA 035 norm and to implement this norm during execution of a research study. Accordingly, documents were prepared and routines were established such as the registration of non-conformities, traceability of research data and equipment calibration. The implementation of a quality system, the setting of a laboratory focused on basic research is feasible once certain structural changes are made. Importantly, impacts were noticed during the process, which could be related to several improvements in the laboratory routine.

  5. Viability of a Bioelectrical Signal Acquisition System Energized by Cellphone with NFC.

    PubMed

    Kay, Marcel Seiji; Iaione, Fábio

    2015-01-01

    Currently, smartphones are used in various systems in the medical field due to the presence of various features, notably Near Field Communication (NFC). NFC utilizes communication technology and an energy supply based on electromagnetic induction. One of the most common medical tests is the electrocardiogram (ECG), through which various heart diseases can be diagnosed. The objective of this study is to evaluate the feasibility of providing power to a bioelectrical signal acquisition module using a mobile phone with NFC. After testing it was indicated that it is possible to construct a passive module to acquire ECG signals using NFC mobile phone.

  6. Detection performance of laser range-gated imaging system

    NASA Astrophysics Data System (ADS)

    Xu, Jun; Li, Xiaofeng; Luo, Jijun; Zhang, Shengxiu; Xu, Yibin

    2010-10-01

    Laser radar is rapidly developing towards very capable sensors for number of applications such as military sensing and guidance, auto collision avoidance, robotic vision and atmospheric sensing. In this paper, the detection performance of non-scanned Laser Rang-gated (LRG) imaging system is studied. In order to compute the detection range of laser active imaging system, the range equation is derived by using laser illuminating model and considering factors which affect system imaging quality. According to the principle of laser radar and the characters of objects and the detectors in special applied setting, it mainly deduced the non-scanned laser radar range equation of the range-gated system, meanwhile, the SNR model of non-scanned LRG imaging system is set up. Then, relationship of the detection probability, the false alarm probability and the signal-to-noise ratio in the non-scanned LRG imaging system are analyzed, the influence factors of system's performance are pointed out, and the solution is proposed. The detection performance simulation software of non-scanned LRG imaging system is designed with MATLAB and the performance of the imaging system is simulated.

  7. Comparison of motion and stereo methods in passive ranging systems

    NASA Technical Reports Server (NTRS)

    Sridhar, Banavar; Suorsa, Raymond

    1991-01-01

    The authors compare the estimates in passive ranging systems using motion and stereo approaches. It is shown that an integrated approach is necessary to provide better range estimates over a field-of-view (FOV) of interest in helicopter flight. The recursive approach for processing a sequence of stereo images, described together with a recursive motion algorithm (RMA), provides the basis for an integrated method to provide more accurate range information. Results based on motion sequences of stereo images are presented.

  8. The Neuman Systems Model Institute: testing middle-range theories.

    PubMed

    Gigliotti, Eileen

    2003-07-01

    The credibility of the Neuman systems model can only be established through the generation and testing of Neuman systems model-derived middle-range theories. However, due to the number and complexity of Neuman systems model concepts/concept interrelations and the diversity of middle-range theory concepts linked to these Neuman systems model concepts by researchers, no explicit middle-range theories have yet been derived from the Neuman systems model. This article describes the development of an organized program for the systematic study of the Neuman systems model. Preliminary work, already accomplished, is detailed, and a tentative plan for the completion of further preliminary work as well as beginning the actual research conduction phase is proposed.

  9. Viability of karezes (ancient water supply systems in Afghanistan) in a changing world

    NASA Astrophysics Data System (ADS)

    Macpherson, G. L.; Johnson, W. C.; Liu, Huan

    2015-09-01

    The Afghanistan population living far from rivers relies upon groundwater delivered from karezes (sub-horizontal tunnels). Karezes exploit unconfined groundwater in alluvial fans recharged largely by snowmelt from the Hindu Kush, the central mountain range of the country. Since the multi-year drought that began in 1998, many karezes have stopped flowing. This study characterizes the hydraulics of a kariz, the potential for reduced groundwater recharge because of climate change, and the impact of increasing population on kariz water production. A typical kariz in Afghanistan is 1-2 km long with a cross-section of 1-2 m2 and gradient of 1 m km-1. MODFLOW simulations show that water delivery from a kariz can be modeled by imposing a high ratio of kariz hydraulic conductivity to aquifer hydraulic conductivity on the cells representing the kariz. The model is sensitive to hydraulic conductivity, kariz gradient, and length of the kariz in contact with the water table. Precipitation data are scarce in Afghanistan, but regional data show a long-term trend of decreased snow cover, and therefore strong likelihood of decreased aquifer recharge. Population in Afghanistan has increased at a rate of about 2.2 % over the past several decades. An assessment of a six-district region within Kandahar Province where karezes are the most likely source of water indicates that water demand could have caused water tables to decline by 0.8-5.6 m, more than enough to cause karezes to stop flowing. These results suggest that kariz water production is not sustainable under current climate- and population-growth trends.

  10. Viability of karezes (ancient water supply systems in Afghanistan) in a changing world

    NASA Astrophysics Data System (ADS)

    Macpherson, G. L.; Johnson, W. C.; Liu, Huan

    2017-07-01

    The Afghanistan population living far from rivers relies upon groundwater delivered from karezes (sub-horizontal tunnels). Karezes exploit unconfined groundwater in alluvial fans recharged largely by snowmelt from the Hindu Kush, the central mountain range of the country. Since the multi-year drought that began in 1998, many karezes have stopped flowing. This study characterizes the hydraulics of a kariz, the potential for reduced groundwater recharge because of climate change, and the impact of increasing population on kariz water production. A typical kariz in Afghanistan is 1-2 km long with a cross-section of 1-2 m2 and gradient of 1 m km-1. MODFLOW simulations show that water delivery from a kariz can be modeled by imposing a high ratio of kariz hydraulic conductivity to aquifer hydraulic conductivity on the cells representing the kariz. The model is sensitive to hydraulic conductivity, kariz gradient, and length of the kariz in contact with the water table. Precipitation data are scarce in Afghanistan, but regional data show a long-term trend of decreased snow cover, and therefore strong likelihood of decreased aquifer recharge. Population in Afghanistan has increased at a rate of about 2.2 % over the past several decades. An assessment of a six-district region within Kandahar Province where karezes are the most likely source of water indicates that water demand could have caused water tables to decline by 0.8-5.6 m, more than enough to cause karezes to stop flowing. These results suggest that kariz water production is not sustainable under current climate- and population-growth trends.

  11. Viability Conditions for a Compartmentalized Protometabolic System: A Semi-Empirical Approach

    PubMed Central

    Piedrafita, Gabriel; Ruiz-Mirazo, Kepa; Monnard, Pierre-Alain; Cornish-Bowden, Athel; Montero, Francisco

    2012-01-01

    In this work we attempt to find out the extent to which realistic prebiotic compartments, such as fatty acid vesicles, would constrain the chemical network dynamics that could have sustained a minimal form of metabolism. We combine experimental and simulation results to establish the conditions under which a reaction network with a catalytically closed organization (more specifically, an ()-system) would overcome the potential problem of self-suffocation that arises from the limited accessibility of nutrients to its internal reaction domain. The relationship between the permeability of the membrane, the lifetime of the key catalysts and their efficiency (reaction rate enhancement) turns out to be critical. In particular, we show how permeability values constrain the characteristic time scale of the bounded protometabolic processes. From this concrete and illustrative example we finally extend the discussion to a wider evolutionary context. PMID:22761803

  12. Clathrin Heavy Chain Is Important for Viability, Oviposition, Embryogenesis and, Possibly, Systemic RNAi Response in the Predatory Mite Metaseiulus occidentalis

    PubMed Central

    Wu, Ke; Hoy, Marjorie A.

    2014-01-01

    Clathrin heavy chain has been shown to be important for viability, embryogenesis, and RNA interference (RNAi) in arthropods such as Drosophila melanogaster. However, the functional roles of clathrin heavy chain in chelicerate arthropods, such as the predatory mite Metaseiulus occidentalis, remain unknown. We previously showed that dsRNA ingestion, followed by feeding on spider mites, induced systemic and robust RNAi in M. occidentalis females. In the current study, we performed a loss-of-function analysis of the clathrin heavy chain gene in M. occidentalis using RNAi. We showed that ingestion of clathrin heavy chain dsRNA by M. occidentalis females resulted in gene knockdown and reduced longevity. In addition, clathrin heavy chain dsRNA treatment almost completely abolished oviposition by M. occidentalis females and the few eggs produced did not hatch. Finally, we demonstrated that clathrin heavy chain gene knockdown in M. occidentalis females significantly reduced a subsequent RNAi response induced by ingestion of cathepsin L dsRNA. The last finding suggests that clathrin heavy chain may be involved in systemic RNAi responses mediated by orally delivered dsRNAs in M. occidentalis. PMID:25329675

  13. Entropy-Based TOA Estimation and SVM-Based Ranging Error Mitigation in UWB Ranging Systems

    PubMed Central

    Yin, Zhendong; Cui, Kai; Wu, Zhilu; Yin, Liang

    2015-01-01

    The major challenges for Ultra-wide Band (UWB) indoor ranging systems are the dense multipath and non-line-of-sight (NLOS) problems of the indoor environment. To precisely estimate the time of arrival (TOA) of the first path (FP) in such a poor environment, a novel approach of entropy-based TOA estimation and support vector machine (SVM) regression-based ranging error mitigation is proposed in this paper. The proposed method can estimate the TOA precisely by measuring the randomness of the received signals and mitigate the ranging error without the recognition of the channel conditions. The entropy is used to measure the randomness of the received signals and the FP can be determined by the decision of the sample which is followed by a great entropy decrease. The SVM regression is employed to perform the ranging-error mitigation by the modeling of the regressor between the characteristics of received signals and the ranging error. The presented numerical simulation results show that the proposed approach achieves significant performance improvements in the CM1 to CM4 channels of the IEEE 802.15.4a standard, as compared to conventional approaches. PMID:26007726

  14. Entropy-Based TOA Estimation and SVM-Based Ranging Error Mitigation in UWB Ranging Systems.

    PubMed

    Yin, Zhendong; Cui, Kai; Wu, Zhilu; Yin, Liang

    2015-05-21

    The major challenges for Ultra-wide Band (UWB) indoor ranging systems are the dense multipath and non-line-of-sight (NLOS) problems of the indoor environment. To precisely estimate the time of arrival (TOA) of the first path (FP) in such a poor environment, a novel approach of entropy-based TOA estimation and support vector machine (SVM) regression-based ranging error mitigation is proposed in this paper. The proposed method can estimate the TOA precisely by measuring the randomness of the received signals and mitigate the ranging error without the recognition of the channel conditions. The entropy is used to measure the randomness of the received signals and the FP can be determined by the decision of the sample which is followed by a great entropy decrease. The SVM regression is employed to perform the ranging-error mitigation by the modeling of the regressor between the characteristics of received signals and the ranging error. The presented numerical simulation results show that the proposed approach achieves significant performance improvements in the CM1 to CM4 channels of the IEEE 802.15.4a standard, as compared to conventional approaches.

  15. Viability Assessment of a Repository at Yucca Mountain. Volume 3: Total System Performance Assessment

    SciTech Connect

    1998-12-01

    This volume reports the development of TSPA for the VA. This first section defines the general process involved in developing any TSPA, it describes the overall TSPA process as implemented by programs in the US and elsewhere in the world, and discusses the acceptability of TSPA as a process or tool for analyzing a nuclear waste repository system. Section 2 discusses the more specific use of the TSPA process for the TSPA-VA for Yucca Mountain, including goals, approach, and methods. It also includes a very brief synopsis of TSPA-VA results. Section 3 briefly discusses each of the component models that comprise the TSPA-VA. Each TSPA component model represents a discrete set of processes. The TSPA-VA components are: unsaturated zone flow, thermal hydrology, near- field geochemical environment, waste package degradation, waste form alteration and mobilization, unsaturated zone transport, saturated zone flow and transport, and biosphere. For each of these components, this section introduces the conceptualization of each individual process, describes the data sources, and discusses model parameter development and computer methods used to simulate each component. Section 4 explains the mechanics of how the individual TSPA components were combined into a ''base case'' and then provides the ''expected value'' results of a deterministic base case analysis. Section 4 also contains a description of the probabilistic analyses and results that help determine the relative importance of the various TSPA components and the data used to describe the components. Section 5 addresses sensitivity studies run for each of the TSPA components to understand how uncertainty in various parameters within a component change the TSPA results. Section 6 presents the findings of the sensitivity studies run on the various components in Section 5, and prioritizes the findings of the entire set of uncertainty and sensitivity studies of the components relative to each other. Section 6 also discusses

  16. Skin mounted accelerometer system for measuring knee range of motion.

    PubMed

    McGinnis, Ryan S; Patel, Shyamal; Silva, Ikaro; Mahadevan, Nikhil; DiCristofaro, Steve; Jortberg, Elise; Ceruolo, Melissa; Aranyosi, A J

    2016-08-01

    Sufficient range of motion of the knee joint is necessary for performing many activities of daily living. Ambulatory monitoring of knee function can provide valuable information about progression of diseases like knee osteoarthritis and recovery after surgical interventions like total knee arthroplasty. In this paper, we describe a skin-mounted, conformal, accelerometer-based system for measuring knee angle and range of motion that does not require a skilled operator to apply devices. We establish the accuracy of this technique with respect to clinical gold standard goniometric measurements on a dataset collected from normative subjects during the performance of repeated bouts of knee flexion and extension tests. Results show that knee angle and range of motion estimates are highly correlated with goniometer measurements, and track differences in knee angle and range of motion to within 1%. These results demonstrate the ability of this system to characterize knee angle and range of motion, enabling future longitudinal monitoring of knee motion in naturalistic environments.

  17. Electrochemical sensing of hepatocyte viability.

    PubMed

    Tsai, Hweiyan; Tsai, Shang-heng; Ting, Wei-Jen; Hu, Chao-Chin; Fuh, C Bor

    2014-05-21

    We investigated the use of amperometric and chronoamperometric methods with a double mediator system and screen-printed electrodes (SPEs) for the electrochemical sensing of hepatocyte viability. Cell counts were determined based on measuring cellular respiration via interaction of electroactive redox mediators. The oxidation currents of chronoamperometric measurement were proportional to the concentrations of ferrocyanide which was produced via interaction of cellular respiration, succinate and ferricyanide. The integrated oxidation charges increased linearly with the density of the cultured primary rat hepatocytes over a range of 1 × 10(5) to 5 × 10(5) cells per well (slope = 1.98 (±0.08) μC per 10(5) cells; R(2) = 0.9969), and the detection limit was 7600 (±300) cells per well based on S/N = 3. Each density of cells was cultured in triple replicates and individual cell samples were evaluated. The results of the cytotoxic effect of the chronoamperometric method are comparable to those of the tetrazolium-based colorimetric assay. The chronoamperometric method with ferricyanide and succinate mediators is an efficient, alternative method for assessing the viability of primary hepatocytes which can be completed in 20 min. Succinate did not provide an efficient electron shuttle between cytosolic respiratory redox activity of cancer cells and extracellular ferricyanide, an effect that may be useful for distinguishing hepatocarcinoma cells from healthy hepatocytes.

  18. The airborne laser ranging system, its capabilities and applications

    NASA Technical Reports Server (NTRS)

    Kahn, W. D.; Degnan, J. J.; Englar, T. S., Jr.

    1982-01-01

    The airborne laser ranging system is a multibeam short pulse laser ranging system on board an aircraft. It simultaneously measures the distances between the aircraft and six laser retroreflectors (targets) deployed on the Earth's surface. The system can interrogate over 100 targets distributed over an area of 25,000 sq, kilometers in a matter of hours. Potentially, a total of 1.3 million individual range measurements can be made in a six hour flight. The precision of these range measurements is approximately + or - 1 cm. These measurements are used in procedure which is basically an extension of trilateration techniques to derive the intersite vector between the laser ground targets. By repeating the estimation of the intersite vector, strain and strain rate errors can be estimated. These quantities are essential for crustal dynamic studies which include determination and monitoring of regional strain in the vicinity of active fault zones, land subsidence, and edifice building preceding volcanic eruptions.

  19. No association between plant mating system and geographic range overlap.

    PubMed

    Grossenbacher, Dena; Briscoe Runquist, Ryan D; Goldberg, Emma E; Brandvain, Yaniv

    2016-01-01

    Automatic self-fertilization may influence the geography of speciation, promote reproductive isolation between incipient species, and lead to ecological differentiation. As such, selfing taxa are predicted to co-occur more often with their closest relatives than are outcrossing taxa. Despite suggestions that this pattern may be general, the extent to which mating system influences range overlap in close relatives has not been tested formally across a diverse group of plant species pairs. We tested for a difference in range overlap between species pairs for which zero, one, or both species are selfers, using data from 98 sister species pairs in 20 genera across 15 flowering plant families. We also used divergence time estimates from time-calibrated phylogenies to ask how range overlap changes with divergence time and whether this effect depends on mating system. We found no evidence that automatic self-fertilization influenced range overlap of closely related plant species. Sister pairs with more recent divergence times had modestly greater range overlap, but this effect did not depend on mating system. The absence of a strong influence of mating system on range overlap suggests that mating system plays a minor or inconsistent role compared with many other mechanisms potentially influencing the co-occurrence of close relatives. © 2016 Botanical Society of America.

  20. High speed high dynamic range high accuracy measurement system

    SciTech Connect

    Deibele, Craig E.; Curry, Douglas E.; Dickson, Richard W.; Xie, Zaipeng

    2016-11-29

    A measuring system includes an input that emulates a bandpass filter with no signal reflections. A directional coupler connected to the input passes the filtered input to electrically isolated measuring circuits. Each of the measuring circuits includes an amplifier that amplifies the signal through logarithmic functions. The output of the measuring system is an accurate high dynamic range measurement.

  1. Updating range surveys using a geographic information system

    USGS Publications Warehouse

    Eidenshink, Jeffery C.; Sjaastad, David C.

    1985-01-01

    A spatial database was developed for the Fort Berthold Indian Reservation in North Dakota to demonstrate the use of a geographic information system for natural resource management. A key component of the digital database was a detailed soil survey. Range site boundaries were derived by aggregating soil mapping units on the basis on interpretations from the published soil surveys. The problem was that no range survey data including stocking rates and condition class were available for the soil-survey-derived range sites. The only available range survey was a survey that was based on range site delineations from a Missouri River Basin Inventory (MRBI) program conducted in 1961, prior to the availability of soil survey data. The MRBI survey information was correlated with the revised range sites derived from the soil surveys to device stocking rates and condition classes. A 1:24,000-scale map which included revised range site boundaries and management boundaries was produced for each township within the reservation. All polygons on the maps were uniquely labeled to permit discrimination of the potential differences in range site stocking rates due to grazing management practices. The maps and the associated polygon attribute data were merged with maps of the MRBI transect information to derive the stocking rate and condition class for each revised range site within a management unit. The resulting database components were a map of revised range site boundaries within management units and an associated tabular file containing attribute information including stocking rate and condition class.

  2. Test method on infrared system range based on space compression

    NASA Astrophysics Data System (ADS)

    Chen, Zhen-xing; Shi, Sheng-bing; Han, Fu-li

    2016-09-01

    Infrared thermal imaging system generates image based on infrared radiation difference between object and background and is a passive work mode. Range is important performance and necessary appraised test item in appraisal test for infrared system. In this paper, aim is carrying out infrared system range test in laboratory , simulated test ground is designed based on object equivalent, background analog, object characteristic control, air attenuation characteristic, infrared jamming analog and so on, repeatable and controllable tests are finished, problem of traditional field test method is solved.

  3. On-line range prediction system, part 2

    NASA Technical Reports Server (NTRS)

    Levan, Nhan

    1988-01-01

    The on-line range prediction system is designed for providing a prediction of the target range in the case of a laser data dropout. It consists of real time implementation of a Kalman filter on an IBM PC/AT equipped with necessary hardware. The system was set up and tested at Crows Landing in the Fall of 1987. The improvements made on the on-line range prediction system during 1988 are examined. Solutions are proposed and discussed to the several problems encountered during system tests. Then, the improvements made on the filter software are explained, namely, accounting for the time lag and providing data continously. Finally, the ideas are mentioned that can be considered in the future.

  4. Improvements in medium range weather forecasting system of India

    NASA Astrophysics Data System (ADS)

    Prasad, V. S.; Mohandas, Saji; Dutta, Surya Kanti; Gupta, M. Das; Iyengar, G. R.; Rajagopal, E. N.; Basu, Swati

    2014-03-01

    Medium range weather forecasts are being generated in real time using Global Data Assimilation Forecasting System (GDAFS) at NCMRWF since 1994. The system has been continuously upgraded in terms of data usage, assimilation and forecasting system. Recently this system was upgraded to a horizontal resolution of T574 (about 22 km) with 64 levels in vertical. The assimilation scheme of this upgraded system is based on the latest Grid Statistical Interpolation (GSI) scheme and it has the provision to use most of available meteorological and oceanographic satellite datasets besides conventional meteorological observations. The new system has an improved procedure for relocating tropical cyclone to its observed position with the correct intensity. All these modifications have resulted in improvement of skill of medium range forecasts by about 1 day.

  5. Range Information Systems Management (RISM) Phase 1 Report

    NASA Technical Reports Server (NTRS)

    Bastin, Gary L.; Harris, William G.; Nelson, Richard A.

    2002-01-01

    RISM investigated alternative approaches, technologies, and communication network architectures to facilitate building the Spaceports and Ranges of the future. RISM started by document most existing US ranges and their capabilities. In parallel, RISM obtained inputs from the following: 1) NASA and NASA-contractor engineers and managers, and; 2) Aerospace leaders from Government, Academia, and Industry, participating through the Space Based Range Distributed System Working Group (SBRDSWG), many of whom are also; 3) Members of the Advanced Range Technology Working Group (ARTWG) subgroups, and; 4) Members of the Advanced Spaceport Technology Working Group (ASTWG). These diverse inputs helped to envision advanced technologies for implementing future Ranges and Range systems that builds on today s cabled and wireless legacy infrastructures while seamlessly integrating both today s emerging and tomorrow s building-block communication techniques. The fundamental key is to envision a transition to a Space Based Range Distributed Subsystem. The enabling concept is to identify the specific needs of Range users that can be solved through applying emerging communication tech

  6. Tonopah Test Range EGS graphics tracking display system: HP370

    SciTech Connect

    Meyer, R.H.; Bauhs, K.C.

    1994-08-01

    This report describes the HP370 component of the Enhanced Graphics System (EGS) used at Tonopah Test Range (TTR). Selected Radar data is fed into the computer systems and the resulting tracking symbols are displayed on high-resolution video monitors in real time. These tracking symbols overlay background maps and are used for monitoring/controlling various flight vehicles. This report discusses both the operational aspects and the internal configuration of the HP370 Workstation portion of the EGS system.

  7. A wide dynamic range x-ray streak camera system

    SciTech Connect

    Niu Lihong; Yang Qinlao; Niu Hanben; Liao Hua; Zhou Junlan; Ding Yunkun

    2008-02-15

    An x-ray streak camera with wide dynamic range and a large slit photocathode of 30 mm length has been developed and calibrated. In order to achieve wide dynamic range, a conventional streak tube has been improved and the camera system has been designed without microchannel plate electron amplifier. As a result, a dynamic range of 922 is achieved in a single shot mode with laser pulse of 30 ps (full width at half maximum) at time resolution of better than 31 ps.

  8. New focal plane detector system for the broad range spectrometer

    SciTech Connect

    Sjoreen, T.P.

    1984-01-01

    A focal plane detector system consisting of a vertical drift chamber, parallel plate avalanche counters, and an ionization chamber with segmented anodes has been installed in the Broad Range Spectrometer at the Holifield Facility at Oak Ridge. The system, which has been designed for use with light-heavy ions with energies ranging from 10 to 25 MeV/amu, has a position resolution of approx. 0.1 mm, a scattering angle resolution of approx. 3 mrad, and a mass resolution of approx. 1/60.

  9. Method for large-range structured light system calibration.

    PubMed

    An, Yatong; Bell, Tyler; Li, Beiwen; Xu, Jing; Zhang, Song

    2016-11-20

    Structured light system calibration often requires the usage of a calibration target with a similar size as the field of view (FOV), which brings challenges to a large-range structured light system calibration since fabricating large calibration targets is difficult and expensive. This paper presents a large-range system calibration method that does not need a large calibration target. The proposed method includes two stages: (1) accurately calibrate intrinsics (i.e., focal lengths and principle points) at a near range where both the camera and projector are out of focus, and (2) calibrate the extrinsic parameters (translation and rotation) from camera to projector with the assistance of a low-accuracy, large-range three-dimensional (3D) sensor (e.g., Microsoft Kinect). We have developed a large-scale 3D shape measurement system with a FOV of 1120  mm×1900  mm×1000  mm. Experiments demonstrate our system can achieve measurement accuracy as high as 0.07 mm with a standard deviation of 0.80 mm by measuring a 304.8 mm diameter sphere. As a comparison, Kinect V2 only achieved mean error of 0.80 mm with a standard deviation of 3.41 mm for the FOV of measurement.

  10. Passive vibration isolation for long range aerial reconnaissance systems

    NASA Astrophysics Data System (ADS)

    Otoole, J.

    1980-01-01

    The paper discusses an approach to the design of a passive isolation system for a high-altitude, long-range oblique reconnaissance camera which works in conjunction with the active, gyro-stabilized system to attenuate a broad spectrum of vibratory inputs. The proposed design provides an elastic suspension system with minimum damping forces and a damping system which controls the excursions of the camera in the resonant region of disturbance; it has both spring and damping forces in complete balance about the center of gravity of the camera. Mathematical equations and definition in support of the proposed approach are presented together with some pertinent data.

  11. A Cassegrain reflector system for compact range applications

    NASA Technical Reports Server (NTRS)

    Rader, Mark D.; Burnside, Walter D.

    1986-01-01

    An integral part of a compact range is the means of providing a uniform plane wave. A Cassegrain reflector system is one alternative for achieving this goal. Theoretically, this system offers better performance than a simple reflector system. The longer pathlengths in the Cassegrain system lead to a more uniform field in the plane of interest. The addition of the subreflector creates several problems, though. System complexity is increased both in terms of construction and performance analysis. The subreflector also leads to aperture blockage and the orientation of the feed now results in spillover illuminating the target areas as well as the rest of the range. Finally, the addition of the subreflector leads to interaction between the two reflectors resulting in undesired field variations in the plane of interest. These difficulties are addressed and through the concept of blending the surfaces, a Cassegrain reflector system is developed that will provide a uniform plane wave that offers superior performance over large target areas for a given size reflector system. Design and analysis is implemented by considering the main reflector and subreflector separately. Then the system may be put together and the final design and system analysis completed.

  12. Integrated laser/radar satellite ranging and tracking system.

    PubMed

    Hoge, F E

    1974-10-01

    A laser satellite ranging system that is mounted upon and integrated with a microwave tracking radar is reported. The 1-pulse sec/ruby laser transmitter is attached directly to the radar's elevation axis and radiates through a new opening in the radar's parabolic dish. The laser photomultiplier tube receiver utilizes the radar's existing 20-cm diam f11 boresight telescope and observes through a similar symmetrically located opening in the dish. The laser system possesses separate ranging system electronics but shares the radar's timing, computer, and data handling[equation]recording systems. The basic concept of the laser[equation]radar is outlined together with a listing of the numerous advantages over present singular laser rangefinding systems. The developmental laser hardware is described along with preliminary rangefinding results and expectations. The prototype system was assembled to investigate the feasibility of such systems and aid in the development of detailed specifications for an operational system. Both the feasibility and desirability of such systems integrations have been adequately demonstrated.

  13. Effect of short range hydrodynamic on bimodal colloidal gel systems

    NASA Astrophysics Data System (ADS)

    Boromand, Arman; Jamali, Safa; Maia, Joao

    2015-03-01

    Colloidal Gels and disordered arrested systems has been studied extensively during the past decades. Although, they have found their place in multiple industries such as cosmetic, food and so on, their physical principals are still far beyond being understood. The interplay between different types of interactions from quantum scale, Van der Waals interaction, to short range interactions, depletion interaction, and long range interactions such as electrostatic double layer makes this systems challenging from simulation point of view. Many authors have implemented different simulation techniques such as molecular dynamics (MD) and Brownian dynamics (BD) to capture better picture during phase separation of colloidal system with short range attractive force. However, BD is not capable to include multi-body hydrodynamic interaction and MD is limited by the computational resources and is limited to short time and length scales. In this presentation we used Core-modified dissipative particle dynamics (CM-DPD) with modified depletion potential, as a coarse-grain model, to address the gel formation process in short ranged-attractive colloidal suspensions. Due to the possibility to include and separate short and long ranged-hydrodynamic forces in this method we studied the effect of each of those forces on the final morphology and report one of the controversial question in this field on the effect of hydrodynamics on the cluster formation process on bimodal, soft-hard colloidal mixtures.

  14. Compact-range coordinate system established using a laser tracker.

    SciTech Connect

    Gallegos, Floyd H.; Bryce, Edwin Anthony

    2006-12-01

    Establishing a Cartesian coordinate reference system for an existing Compact Antenna Range using the parabolic reflector is presented. A SMX (Spatial Metrix Corporation) M/N 4000 laser-based coordinate measuring system established absolute coordinates for the facility. Electric field characteristics with positional movement correction are evaluated. Feed Horn relocation for alignment with the reflector axis is also described. Reference points are established for follow-on non-laser alignments utilizing a theodolite.

  15. Radio Ranging System for Guidance of Approaching Spacecraft

    NASA Technical Reports Server (NTRS)

    Manikonda, Vikram; vanDoom, Eric

    2008-01-01

    A radio communication and ranging system has been proposed for determining the relative position and orientations of two approaching spacecraft to provide guidance for docking maneuvers. On Earth, the system could be used similarly for guiding approaching aircraft and for automated positioning of large, heavy objects. In principle, the basic idea is to (1) measure distances between radio transceivers on the two spacecraft and (2) compute the relative position and orientations from the measured distances.

  16. Covariance analysis of the airborne laser ranging system

    NASA Technical Reports Server (NTRS)

    Englar, T. S., Jr.; Hammond, C. L.; Gibbs, B. P.

    1981-01-01

    The requirements and limitations of employing an airborne laser ranging system for detecting crustal shifts of the Earth within centimeters over a region of approximately 200 by 400 km are presented. The system consists of an aircraft which flies over a grid of ground deployed retroreflectors, making six passes over the grid at two different altitudes. The retroreflector baseline errors are assumed to result from measurement noise, a priori errors on the aircraft and retroreflector positions, tropospheric refraction, and sensor biases.

  17. Mobile range control center/range safety command destruct and real-time instantaneous impact prediction system

    NASA Technical Reports Server (NTRS)

    Hudson, Sandra Merritt

    1997-01-01

    The mobile range control center/range safety command destruct and real time instantaneous impact prediction system (MRCCS), designed for launching sounding rockets and expendable launch vehicles, is described. The MRCCS provides mission control and range safety support for remote launch sites and is equipped with telemetry and radar data acquisition systems, real time data computation systems, range safety display systems, and command destruct transmitters.

  18. The Quaternary thrust system of the northern Alaska Range

    USGS Publications Warehouse

    Bemis, Sean P.; Carver, Gary A.; Koehler, Richard D.

    2012-01-01

    The framework of Quaternary faults in Alaska remains poorly constrained. Recent studies in the Alaska Range north of the Denali fault add significantly to the recognition of Quaternary deformation in this active orogen. Faults and folds active during the Quaternary occur over a length of ∼500 km along the northern flank of the Alaska Range, extending from Mount McKinley (Denali) eastward to the Tok River valley. These faults exist as a continuous system of active structures, but we divide the system into four regions based on east-west changes in structural style. At the western end, the Kantishna Hills have only two known faults but the highest rate of shallow crustal seismicity. The western northern foothills fold-thrust belt consists of a 50-km-wide zone of subparallel thrust and reverse faults. This broad zone of deformation narrows to the east in a transition zone where the range-bounding fault of the western northern foothills fold-thrust belt terminates and displacement occurs on thrust and/or reverse faults closer to the Denali fault. The eastern northern foothills fold-thrust belt is characterized by ∼40-km-long thrust fault segments separated across left-steps by NNE-trending left-lateral faults. Altogether, these faults accommodate much of the topographic growth of the northern flank of the Alaska Range.Recognition of this thrust fault system represents a significant concern in addition to the Denali fault for infrastructure adjacent to and transecting the Alaska Range. Although additional work is required to characterize these faults sufficiently for seismic hazard analysis, the regional extent and structural character should require the consideration of the northern Alaska Range thrust system in regional tectonic models.

  19. Synbiotic impact of tagatose on viability of Lactobacillus rhamnosus strain GG mediated by the phosphotransferase system (PTS).

    PubMed

    Koh, Ji Hoon; Choi, Seung Hye; Park, Seung Won; Choi, Nag-Jin; Kim, Younghoon; Kim, Sae Hun

    2013-10-01

    Synbiotics, the combination of prebiotics and probiotics, has been shown to produce synergistic effects that promote gastrointestinal well-being of host. Tagatose is a low calorie food ingredient with putative health-promoting benefits. Herein, we investigated its synbiotic impact on the viability of Lactobacillus casei 01 and Lactobacillus rhamnosus strain GG and the potential mechanism involved. Tagatose, as a synbiotic substrate, enhanced the growth of L. casei 01 and L. rhamnosus strain GG compared to other prebiotics. Other gut-indigenous such as Clostridium spp. readily utilized fructooligosaccharide (FOS), the most widely used functional prebiotics, but not tagatose. Additionally, tagatose enhanced probiotic functions of L. casei 01 and L. rhamnosus strain GG by reinforcing their attachment on HT-29 intestine epithelial cells and enhancing their cholesterol-lowering activities. Whole transcriptome study and quantitative real-time polymerase chain reaction (qRT-PCR) test showed that the presence of tagatose in L. rhamnosus strain GG caused induction of a large number of genes associated with carbohydrate metabolism including the phosphotransferase system (PTS). Collectively, these results indicate the tagatose enhanced the growth of L. casei 01 and L. rhamnosus strain GG and their probiotic activities by activating tagatose-associated PTS networks. Importantly, this study highlights the potential application of tagatose and L. casei 01 and/or L. rhamnosus strain GG as a synbiotic partner in functional dairy foods (i.e. yogurt and cheese) and therapeutic dietary supplements. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Upgrading NASA/DOSE laser ranging system control computers

    NASA Technical Reports Server (NTRS)

    Ricklefs, Randall L.; Cheek, Jack; Seery, Paul J.; Emenheiser, Kenneth S.; Hanrahan, William P., III; Mcgarry, Jan F.

    1993-01-01

    Laser ranging systems now managed by the NASA Dynamics of the Solid Earth (DOSE) and operated by the Bendix Field Engineering Corporation, the University of Hawaii, and the University of Texas have produced a wealth on interdisciplinary scientific data over the last three decades. Despite upgrades to the most of the ranging station subsystems, the control computers remain a mix of 1970's vintage minicomputers. These encompass a wide range of vendors, operating systems, and languages, making hardware and software support increasingly difficult. Current technology allows replacement of controller computers at a relatively low cost while maintaining excellent processing power and a friendly operating environment. The new controller systems are now being designed using IBM-PC-compatible 80486-based microcomputers, a real-time Unix operating system (LynxOS), and X-windows/Motif IB, and serial interfaces have been chosen. This design supports minimizing short and long term costs by relying on proven standards for both hardware and software components. Currently, the project is in the design and prototyping stage with the first systems targeted for production in mid-1993.

  1. A novel track imaging system as a range counter

    NASA Astrophysics Data System (ADS)

    Chen, Z.; Matsufuji, N.; Kanayama, S.; Ishida, A.; Kohno, T.; Koba, Y.; Sekiguchi, M.; Kitagawa, A.; Murakami, T.

    2016-05-01

    An image-intensified, camera-based track imaging system has been developed to measure the tracks of ions in a scintillator block. To study the performance of the detector unit in the system, two types of scintillators, a dosimetrically tissue-equivalent plastic scintillator EJ-240 and a CsI(Tl) scintillator, were separately irradiated with carbon ion (12C) beams of therapeutic energy from HIMAC at NIRS. The images of individual ion tracks in the scintillators were acquired by the newly developed track imaging system. The ranges reconstructed from the images are reported here. The range resolution of the measurements is 1.8 mm for 290 MeV/u carbon ions, which is considered a significant improvement on the energy resolution of the conventional ΔE/E method. The detector is compact and easy to handle, and it can fit inside treatment rooms for in-situ studies, as well as satisfy clinical quality assurance purposes.

  2. Entropy production in systems with long range interactions

    NASA Astrophysics Data System (ADS)

    Pakter, Renato; Levin, Yan

    2017-04-01

    On a fine grained scale the Gibbs entropy of an isolated system remains constant throughout its dynamical evolution. This is a consequence of Liouville’s theorem for Hamiltonian systems and appears to contradict the second law of thermodynamics. In reality, however, there is no problem since the thermodynamic entropy should be associated with the Boltzmann entropy, which for non-equilibrium systems is different from Gibbs entropy. The Boltzmann entropy accounts for the microstates which are not accessible from a given initial condition, but are compatible with a given macrostate. In a sense the Boltzmann entropy is a coarse grained version of the Gibbs entropy and will not decrease during the dynamical evolution of a macroscopic system. In this paper we will explore the entropy production for systems with long range interactions. Unlike for short range systems, in the thermodynamic limit, the probability density function for these systems decouples into a product of one particle distribution functions and the coarse grained entropy can be calculated explicitly. We find that the characteristic time for the entropy production scales with the number of particles as {{N}α} , with α >0 , so that in the thermodynamic limit entropy production takes an infinite amount of time.

  3. Broad tuning range filtering system with Optune interferometers

    NASA Astrophysics Data System (ADS)

    Miron, Nicolae

    2008-08-01

    An optical system built with two Optune interferometers cascaded according to Vernier principle has attractive tunable band pass filtering properties for numerous applications. Several characteristics of Optune interferometer such as 0.2 dB insertion loss flatness across at least 90 nm interval, no tuning holes across 240 nm tuning range, quasi-periodic free spectral range and 1 dB insertion loss are key parameters to obtain a cascade with 0.1 nm band pass tunable across minimum 90 nm. Several properties of Optune interferometers are analyzed to build a cascade tunable across minimum 90 nm: the relationships between the free spectral ranges, bandwidths and tuning conditions. It is presented also a cascade prototype with two interferometers having 9.72 nm free spectral range and respectively 11.12 nm free spectral range. The cascade band pass is 0.1 nm tunable with 1 pm accuracy to any arbitrary wavelength across 150 nm free spectral range, without any tuning hole. It has 0.125 ms / 100 nm tuning speed, the insertion loss is less than 3 dB, 50 dB contrast, 0.5 dB flatness and 0.2 dB polarization dependent loss. A controller based on digital signal processor monitors the operation of the cascade to achieve optimum tuning performance.

  4. Missile tracking and range safety: Tracking Interferometer Pathfinder System (TIPS)

    NASA Astrophysics Data System (ADS)

    Dowgiallo, David J.; Rauen, Stephen; Peters, Wendy M.; Polisensky, Emil J.

    2013-05-01

    The tracking of missiles at close range proximity has been an ongoing challenge for many launch environments. The ability to provide accurate missile trajectory information is imperative for range safety and early termination of flight. In an effort to provide a potential solution to tracking issues that have plagued many traditional techniques, the Tracking Interferometer Pathfinder System (TIPS) was developed at the Naval Research Laboratory, Washington, D.C. The paper herein describes the design, field test, and results of an interferometer deployed for missile tracking.

  5. Cost/Benefit Analysis of Marine Corps Range Scheduling Systems

    DTIC Science & Technology

    1991-05-01

    commer- cial vendors and through a bulk buy for the entire six-site range installation requirements. RFMSS costs are shown in Table 2. The RFMSS...Navy Personnel Research and Development Center San Diego, California 92152-6800 TN-91-14 May 1991 AD-A236 647 Cost /Benefit Analysis of Marine Corps...liiiii III1I1I111111E i N NPRDC-TN-91-14 May 1991 Cost /Benefit Analysis of Marine Corps Range Scheduling Systems Gerald L. Jenkins George M. Anastasi

  6. Design of short-range terahertz wave passive detecting system

    NASA Astrophysics Data System (ADS)

    Zhang, Chao; Lou, Guowei; Zhu, Li; Qian, Songsong; Li, Ting

    2016-09-01

    Based on the study of radiation and transmission characteristics on THz waveband, a short-range passive detecting system is designed. The scheme originated from microwave passive detecting system. A prototype was developed following the design of key components including antennas and a harmonic mixer. The system operated at 0.36 THz. A dual-beam Cassegrain antenna was adopted for receiving signals which radiated by object and background. Local oscillator signal was generated by frequency multiplication. Harmonic mixing is adopted for reducing local oscillator signal frequency required by half. Superheterodyne technology is employed for signal acquisition. The system implemented easily. Tests and measurements were taken, which showed that the scheme was feasible and the performance of the prototype system met the design requirements.

  7. The Geoscience Laser Altimetry/Ranging System (GLARS)

    NASA Technical Reports Server (NTRS)

    Cohen, S. C.; Degnan, J. J.; Bufton, J. L.; Garvin, J. B.; Abshire, J. B.

    1986-01-01

    The Geoscience Laser Altimetry Ranging System (GLARS) is a highly precise distance measurement system to be used for making extremely accurate geodetic observations from a space platform. It combines the attributes of a pointable laser ranging system making observations to cube corner retroreflectors placed on the ground with those of a nadir looking laser altimeter making height observations to ground, ice sheet, and oceanic surfaces. In the ranging mode, centimeter-level precise baseline and station coordinate determinations will be made on grids consisting of 100 to 200 targets separated by distances from a few tens of kilometers to about 1000 km. These measurements will be used for studies of seismic zone crustal deformations and tectonic plate motions. Ranging measurements will also be made to a coarser, but globally distributed array of retroreflectors for both precise geodetic and orbit determination applications. In the altimetric mode, relative height determinations will be obtained with approximately decimeter vertical precision and 70 to 100 meter horizontal resolution. The height data will be used to study surface topography and roughness, ice sheet and lava flow thickness, and ocean dynamics. Waveform digitization will provide a measure of the vertical extent of topography within each footprint. The planned Earth Observing System is an attractive candidate platform for GLARS since the GLAR data can be used both for direct analyses and for highly precise orbit determination needed in the reduction of data from other sensors on the multi-instrument platform. (1064, 532, and 355 nm)Nd:YAG laser meets the performance specifications for the system.

  8. Entanglement Area Laws for Long-Range Interacting Systems

    NASA Astrophysics Data System (ADS)

    Gong, Zhe-Xuan; Foss-Feig, Michael; Brandão, Fernando G. S. L.; Gorshkov, Alexey V.

    2017-08-01

    We prove that the entanglement entropy of any state evolved under an arbitrary 1 /rα long-range-interacting D -dimensional lattice spin Hamiltonian cannot change faster than a rate proportional to the boundary area for any α >D +1 . We also prove that for any α >2 D +2 , the ground state of such a Hamiltonian satisfies the entanglement area law if it can be transformed along a gapped adiabatic path into a ground state known to satisfy the area law. These results significantly generalize their existing counterparts for short-range interacting systems, and are useful for identifying dynamical phase transitions and quantum phase transitions in the presence of long-range interactions.

  9. Multipurpose underwater imaging and ranging camera: prototype system performance

    NASA Astrophysics Data System (ADS)

    Gleckler, Anthony D.; Pittner, Anthony

    2000-07-01

    SEACAM is a combination of a digital camera and an underwater sonar range finder that allows the precise range to the target to be measured simultaneously with the image. Given this measured range and the known field of view of the camera, the `plate scale' of the image (i.e., the number of millimeters/pixel) can be precisely determined, allowing for accurate estimates of the target dimensions. Two prototype systems have been developed: a `functional' camera that has all the functional capability of the final camera, but which is not packaged in the final form; and an `ergonomic' prototype that represents the first attempt at the final package design, but which is non-functional.

  10. Ranging Apparatus and Method Implementing Stereo Vision System

    NASA Technical Reports Server (NTRS)

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

    1997-01-01

    A laser-directed ranging system for use in telerobotics applications and other applications involving physically handicapped individuals. The ranging system includes a left and right video camera mounted on a camera platform, and a remotely positioned operator. The position of the camera platform is controlled by three servo motors to orient the roll axis, pitch axis and yaw axis of the video cameras, based upon an operator input such as head motion. A laser is provided between the left and right video camera and is directed by the user to point to a target device. The images produced by the left and right video cameras are processed to eliminate all background images except for the spot created by the laser. This processing is performed by creating a digital image of the target prior to illumination by the laser, and then eliminating common pixels from the subsequent digital image which includes the laser spot. The horizontal disparity between the two processed images is calculated for use in a stereometric ranging analysis from which range is determined.

  11. Effects of turbulence on the geodynamic laser ranging system

    NASA Technical Reports Server (NTRS)

    Churnside, James H.

    1993-01-01

    The Geodynamic Laser Ranging System (GLRS) is one of several instruments being developed by the National Aeronautics and Space Administration (NASA) for implementation as part of the Earth Observing System in the mid-1990s (Cohen et al., 1987; Bruno et al., 1988). It consists of a laser transmitter and receiver in space and an array of retroreflectors on the ground. The transmitter produces short (100 ps) pulses of light at two harmonics (0.532 and 0.355 microns) of the Nd:YAG laser. These propagate to a retroreflector on the ground and return. The receiver collects the reflected light and measures the round-trip transit time. Ranging from several angles accurately determines the position of the retroreflector, and changes in position caused by geophysical processes can be monitored.

  12. The precision of today's satellite laser ranging systems

    NASA Technical Reports Server (NTRS)

    Dunn, Peter J.; Torrence, Mark H.; Hussen, Van S.; Pearlman, Michael R.

    1993-01-01

    Recent improvements in the accuracy of modern satellite laser ranging (SLR) systems are strengthened by the new capability of many instruments to track an increasing number of geodetic satellite targets without significant scheduling conflict. This will allow the refinement of some geophysical parameters, such as solid Earth tidal effects and GM, and the improved temporal resolution of others, such as Earth orientation and station position. Better time resolution for the locations of fixed observatories will allow us to monitor more subtle motions at the stations, and transportable systems will be able to provide indicators of long term trends with shorter occupations. If we are to take advantage of these improvements, care must be taken to preserve the essential accuracy of an increasing volume of range observations at each stage of the data reduction process.

  13. Data Fusion Analysis for Range Test Validation System

    DTIC Science & Technology

    2010-07-14

    for species-specific column densities of chemical clouds to be determined. A low-order, tunable Fabry - Perot 6 etalon provides the spectral...simulants Chemical agent detection Point sensors Standoff sensors A range test validation system (RTVS) was developed under the sponsorship of the...Defense Threat Reduction Agency as a means for validating point and standoff chemical sensors with releases of chemical agent simulants over a test grid

  14. Intelligent liquid surface measuring system based on laser ranging

    NASA Astrophysics Data System (ADS)

    Li, Song; He, Ping'an; Han, Jianzhong; Yu, Feng

    2003-09-01

    Using laser range finder DISTO as a sensor, we developed an intelligent liquid surface measuring system that can be used to measure the depth of liquid. Many problems such as liquid surface reflected in fixed direction, measuring errors caused by reflex reflections and liquid surface fluctuation are solved. Now it is proved by our experiments on the spot that the system would be used in measuring depth of all kind of liquid, especially in combustible or explosive oil and liquefaction gas with the accuracy of +/-3mm.

  15. Conversion properties of short-range autodyne systems

    NASA Astrophysics Data System (ADS)

    Damgov, V. N.

    1990-04-01

    An analysis is made of the conversion properties of Doppler autodyne systems (for use in short-range navigation systems) described by a third-order differential equation. Expressions are obtained for the conversion coefficients of the echo signal from a moving object as a function of the degree of regeneration and detuning of the oscillation circuit of the autodyne, the time constant of the shift circuit, the self-oscillation amplitude, the degree of nonlinearity of the active-element characteristics, and the Doppler-shift frequency.

  16. High Dynamic Range Complex Impedance Measurement System for Petrophysical Usage

    NASA Astrophysics Data System (ADS)

    Chen, R.; He, X.; Yao, H.; Tan, S.; Shi, H.; Shen, R.; Yan, C.; Zeng, P.; He, L.; Qiao, N.; Xi, F.; Zhang, H.; Xie, J.

    2015-12-01

    Spectral induced polarization method (SIP) or complex resistivity method is increasing its application in metalliferous ore exploration, hydrocarbon exploration, underground water exploration, monitoring of environment pollution, and the evaluation of environment remediation. And the measurement of complex resistivity or complex impedance of rock/ore sample and polluted water plays a fundamental role in improving the application effect of SIP and the application scope of SIP. However, current instruments can't guaranty the accuracy of measurement when the resistance of sample is less than 10Ω or great than 100kΩ. A lot of samples, such as liquid, polluted sea water, igneous rock, limestone, and sandstone, can't be measured with reliable complex resistivity result. Therefore, this problem projects a shadow in the basic research and application research of SIP. We design a high precision measurement system from the study of measurement principle, sample holder, and measurement instrument. We design input buffers in a single board. We adopt operation amplifier AD549 in this system because of its ultra-high input impedance and ultra-low current noise. This buffer is good in acquiring potential signal across high impedance sample. By analyzing the sources of measurement error and errors generated by the measurement system, we propose a correction method to remove the error in order to achieve high quality complex impedance measurement for rock and ore samples. This measurement system can improve the measurement range of the complex impedance to 0.1 Ω ~ 10 GΩ with amplitude error less than 0.1% and phase error less than 0.1mrad when frequency ranges as 0.01 Hz ~ 1 kHz. We tested our system on resistors with resistance as 0.1Ω ~ 10 GΩ in frequency range as 1 Hz ~ 1000 Hz, and the measurement error is less than 0.1 mrad. We also compared the result with LCR bridge and SCIP, we can find that the bridge's measuring range only reaches 100 MΩ, SCIP's measuring range

  17. Long-range interacting systems in the unconstrained ensemble.

    PubMed

    Latella, Ivan; Pérez-Madrid, Agustín; Campa, Alessandro; Casetti, Lapo; Ruffo, Stefano

    2017-01-01

    Completely open systems can exchange heat, work, and matter with the environment. While energy, volume, and number of particles fluctuate under completely open conditions, the equilibrium states of the system, if they exist, can be specified using the temperature, pressure, and chemical potential as control parameters. The unconstrained ensemble is the statistical ensemble describing completely open systems and the replica energy is the appropriate free energy for these control parameters from which the thermodynamics must be derived. It turns out that macroscopic systems with short-range interactions cannot attain equilibrium configurations in the unconstrained ensemble, since temperature, pressure, and chemical potential cannot be taken as a set of independent variables in this case. In contrast, we show that systems with long-range interactions can reach states of thermodynamic equilibrium in the unconstrained ensemble. To illustrate this fact, we consider a modification of the Thirring model and compare the unconstrained ensemble with the canonical and grand-canonical ones: The more the ensemble is constrained by fixing the volume or number of particles, the larger the space of parameters defining the equilibrium configurations.

  18. Decision Support Systems for Launch and Range Operations Using Jess

    NASA Technical Reports Server (NTRS)

    Thirumalainambi, Rajkumar

    2007-01-01

    The virtual test bed for launch and range operations developed at NASA Ames Research Center consists of various independent expert systems advising on weather effects, toxic gas dispersions and human health risk assessment during space-flight operations. An individual dedicated server supports each expert system and the master system gather information from the dedicated servers to support the launch decision-making process. Since the test bed is based on the web system, reducing network traffic and optimizing the knowledge base is critical to its success of real-time or near real-time operations. Jess, a fast rule engine and powerful scripting environment developed at Sandia National Laboratory has been adopted to build the expert systems providing robustness and scalability. Jess also supports XML representation of knowledge base with forward and backward chaining inference mechanism. Facts added - to working memory during run-time operations facilitates analyses of multiple scenarios. Knowledge base can be distributed with one inference engine performing the inference process. This paper discusses details of the knowledge base and inference engine using Jess for a launch and range virtual test bed.

  19. Decision Support Systems for Launch and Range Operations Using Jess

    NASA Technical Reports Server (NTRS)

    Thirumalainambi, Rajkumar

    2007-01-01

    The virtual test bed for launch and range operations developed at NASA Ames Research Center consists of various independent expert systems advising on weather effects, toxic gas dispersions and human health risk assessment during space-flight operations. An individual dedicated server supports each expert system and the master system gather information from the dedicated servers to support the launch decision-making process. Since the test bed is based on the web system, reducing network traffic and optimizing the knowledge base is critical to its success of real-time or near real-time operations. Jess, a fast rule engine and powerful scripting environment developed at Sandia National Laboratory has been adopted to build the expert systems providing robustness and scalability. Jess also supports XML representation of knowledge base with forward and backward chaining inference mechanism. Facts added - to working memory during run-time operations facilitates analyses of multiple scenarios. Knowledge base can be distributed with one inference engine performing the inference process. This paper discusses details of the knowledge base and inference engine using Jess for a launch and range virtual test bed.

  20. Long-range interacting systems in the unconstrained ensemble

    NASA Astrophysics Data System (ADS)

    Latella, Ivan; Pérez-Madrid, Agustín; Campa, Alessandro; Casetti, Lapo; Ruffo, Stefano

    2017-01-01

    Completely open systems can exchange heat, work, and matter with the environment. While energy, volume, and number of particles fluctuate under completely open conditions, the equilibrium states of the system, if they exist, can be specified using the temperature, pressure, and chemical potential as control parameters. The unconstrained ensemble is the statistical ensemble describing completely open systems and the replica energy is the appropriate free energy for these control parameters from which the thermodynamics must be derived. It turns out that macroscopic systems with short-range interactions cannot attain equilibrium configurations in the unconstrained ensemble, since temperature, pressure, and chemical potential cannot be taken as a set of independent variables in this case. In contrast, we show that systems with long-range interactions can reach states of thermodynamic equilibrium in the unconstrained ensemble. To illustrate this fact, we consider a modification of the Thirring model and compare the unconstrained ensemble with the canonical and grand-canonical ones: The more the ensemble is constrained by fixing the volume or number of particles, the larger the space of parameters defining the equilibrium configurations.

  1. Peristaltic pump-based low range pressure sensor calibration system

    SciTech Connect

    Vinayakumar, K. B.; Naveen Kumar, G.; Rajanna, K. E-mail: krajanna2011@gmail.com; Nayak, M. M.; Dinesh, N. S.

    2015-11-15

    Peristaltic pumps were normally used to pump liquids in several chemical and biological applications. In the present study, a peristaltic pump was used to pressurize the chamber (positive as well negative pressures) using atmospheric air. In the present paper, we discuss the development and performance study of an automatic pressurization system to calibrate low range (millibar) pressure sensors. The system includes a peristaltic pump, calibrated pressure sensor (master sensor), pressure chamber, and the control electronics. An in-house developed peristaltic pump was used to pressurize the chamber. A closed loop control system has been developed to detect and adjust the pressure leaks in the chamber. The complete system has been integrated into a portable product. The system performance has been studied for a step response and steady state errors. The system is portable, free from oil contaminants, and consumes less power compared to existing pressure calibration systems. The veracity of the system was verified by calibrating an unknown diaphragm based pressure sensor and the results obtained were satisfactory.

  2. Peristaltic pump-based low range pressure sensor calibration system

    NASA Astrophysics Data System (ADS)

    Vinayakumar, K. B.; Naveen Kumar, G.; Nayak, M. M.; Dinesh, N. S.; Rajanna, K.

    2015-11-01

    Peristaltic pumps were normally used to pump liquids in several chemical and biological applications. In the present study, a peristaltic pump was used to pressurize the chamber (positive as well negative pressures) using atmospheric air. In the present paper, we discuss the development and performance study of an automatic pressurization system to calibrate low range (millibar) pressure sensors. The system includes a peristaltic pump, calibrated pressure sensor (master sensor), pressure chamber, and the control electronics. An in-house developed peristaltic pump was used to pressurize the chamber. A closed loop control system has been developed to detect and adjust the pressure leaks in the chamber. The complete system has been integrated into a portable product. The system performance has been studied for a step response and steady state errors. The system is portable, free from oil contaminants, and consumes less power compared to existing pressure calibration systems. The veracity of the system was verified by calibrating an unknown diaphragm based pressure sensor and the results obtained were satisfactory.

  3. Peristaltic pump-based low range pressure sensor calibration system.

    PubMed

    Vinayakumar, K B; Naveen Kumar, G; Nayak, M M; Dinesh, N S; Rajanna, K

    2015-11-01

    Peristaltic pumps were normally used to pump liquids in several chemical and biological applications. In the present study, a peristaltic pump was used to pressurize the chamber (positive as well negative pressures) using atmospheric air. In the present paper, we discuss the development and performance study of an automatic pressurization system to calibrate low range (millibar) pressure sensors. The system includes a peristaltic pump, calibrated pressure sensor (master sensor), pressure chamber, and the control electronics. An in-house developed peristaltic pump was used to pressurize the chamber. A closed loop control system has been developed to detect and adjust the pressure leaks in the chamber. The complete system has been integrated into a portable product. The system performance has been studied for a step response and steady state errors. The system is portable, free from oil contaminants, and consumes less power compared to existing pressure calibration systems. The veracity of the system was verified by calibrating an unknown diaphragm based pressure sensor and the results obtained were satisfactory.

  4. Real architecture For 3D Tissue (RAFT™) culture system improves viability and maintains insulin and glucagon production of mouse pancreatic islet cells.

    PubMed

    Szebeni, Gabor J; Tancos, Zsuzsanna; Feher, Liliana Z; Alfoldi, Robert; Kobolak, Julianna; Dinnyes, Andras; Puskas, Laszlo G

    2017-04-01

    There is an unmet medical need for the improvement of pancreatic islet maintenance in culture. Due to restricted donor availability it is essential to ameliorate islet viability and graft engraftment. The aim of this study was to compare the standard tissue culture techniques with the advanced Real Architecture For 3D Tissue (RAFT™) culture system in terms of viability and hormone production. Here, we first report that islets embedded in RAFT™ collagen type I advanced tissue culture system maintain their tissue integrity better than in monolayer and suspension cultures. The Calcein violet assay and Annexin V/propidium-iodide staining show higher cell viability in the RAFT™ culture system. Quantitative real-time PCR data showed that RAFT™ increases insulin expression after 18 days in culture compared to traditional methods. Enhanced insulin and glucagon production was further verified by immunofluorescent staining in a time-course manner. These results indicate that RAFT™ tissue culture platform can be a promising tool to maintain pancreatic islet spheroid integrity and culture islets for downstream high throughput pharmacological studies ex vivo.

  5. Prototype air cleaning system for a firing range

    SciTech Connect

    Glissmeyer, J.A.; Mishima, J.; Bamberger, J.A.

    1985-01-01

    This report recommends air cleaning system components for the US Army Ballistics Research Laboratory's new large-caliber firing range, which is used for testing depleted uranium (DU) penetrators. The new air cleaning system has lower operating costs during the life of the system compared to that anticipated for the existing air cleaning system. The existing system consists of three banks of filters in series; the first two banks are prefilters and the last are high-efficiency particulate air (HEPA) filters. The principal disadvantage of the existing filters is that they are not cleanable and reusable. Pacific Northwest Laboratory focused the search for alternate air cleaning equipment on devices that do not employ liquids as part of the particle collection mechanism. Collected dry particles were assumed preferable to a liquid waste stream. The dry particle collection devices identified included electrostatic precipitators; inertial separators using turning vanes or cyclones; and several devices employing a filter medium such as baghouses, cartridge houses, cleanable filters, and noncleanable filters similar to those in the existing system. The economics of practical air cleaning systems employing the dry particle collection devices were evaluated in 294 different combinations. 7 references, 21 figures, 78 tables.

  6. Economic and financial viability of small-scale dairy systems in central Mexico: economic scenario 2010-2018.

    PubMed

    Posadas-Domínguez, R R; Callejas-Juárez, N; Arriaga-Jordán, C M; Martínez-Castañeda, F E

    2016-12-01

    A simulation Monte Carlo model was used to assess the economic and financial viability of 130 small-scale dairy farms in central Mexico, through a Representative Small-Scale Dairy Farm. Net yields were calculated for a 9-year planning horizon by means of simulated values for the distribution of input and product prices taking 2010 as base year and considering four scenarios which were compared against the scenario of actual production. The other scenarios were (1) total hiring in of needed labour; (2) external purchase of 100 % of inputs and (3) withdrawal of subsidies to production. A stochastic modelling approach was followed to determine the scenario with the highest economic and financial viability. Results show a viable economic and financial situation for the real production scenario, as well as the scenarios for total hiring of labour and of withdrawal of subsidies, but the scenario when 100 % of feed inputs for the herd are bought-in was not viable.

  7. E-prescription as a tool for improving services and the financial viability of healthcare systems: the case of the Greek national e-prescription system.

    PubMed

    Pangalos, G; Sfyroeras, V; Pagkalos, I

    2014-01-01

    E-prescription systems can help improve patient service, safety and quality of care. They can also help achieve better compliance for the patients and better alignment with the guidelines for the practitioners. The recently implemented national e-prescription system in Greece already covers approximately 85% of all prescriptions prescribed in Greece today (approximately 5.5 million per month). The system has not only contributed already in significant changes towards improving services and better monitoring and planning of public health, but also substantially helped to contain unnecessary expenditure related to medication use and improve transparency and administrative control. Such issues have gained increasing importance not only for Greece but also for many other national healthcare systems that have to cope with the continuous rise of medication expenditure. Our implementation has, therefore, shown that besides their importance for improving services, national e-prescription systems can also provide a valuable tool for better utilisation of resources and for containing unnecessary healthcare costs, thus contributing to the improvement of the financial stability and viability of the overall healthcare system.

  8. Long-range correlations in quantum systems with aperiodic Hamiltonians

    NASA Astrophysics Data System (ADS)

    Lin, Zhifang; Goda, Masaki

    1997-03-01

    An efficient algorithm for the computation of correlation function (CF) at very long distances is presented for quantum systems whose Hamiltonian is formed by the substitution aperiodic sequence alternating over unit intervals in time or space. The algorithm reorganizes the expression of the CF in such a way that the evaluation of the CF at distances equal to some special numbers is related to a family of graphs generated recursively. As examples of applications, we evaluate the CF, over unprecedentedly long time intervals up to order of 1012, for aperiodic two-level systems subject to kicking perturbations that are in the Thue-Morse, the period-doubling, and the Rudin-Shapiro sequences, respectively. Our results show the presence of long-range correlations in all these aperiodic quantum systems.

  9. On the assessment of biological life support system operation range

    NASA Astrophysics Data System (ADS)

    Bartsev, Sergey

    Biological life support systems (BLSS) can be used in long-term space missions only if well-thought-out assessment of the allowable operating range is obtained. The range has to account both permissible working parameters of BLSS and the critical level of perturbations of BLSS stationary state. Direct approach to outlining the range by statistical treatment of experimental data on BLSS destruction seems to be not applicable due to ethical, economical, and saving time reasons. Mathematical model is the unique tool for the generalization of experimental data and the extrapolation of the revealed regularities beyond empirical experience. The problem is that the quality of extrapolation depends on the adequacy of corresponding model verification, but good verification requires wide range of experimental data for fitting, which is not achievable for manned experimental BLSS. Possible way to improve the extrapolation quality of inevitably poorly verified models of manned BLSS is to extrapolate general tendency obtained from unmanned LSS theoretical-experiment investigations. Possibilities and limitations of such approach are discussed.

  10. Chasing Salmonella Typhimurium in free range egg production system.

    PubMed

    Chousalkar, Kapil; Gole, Vaibhav; Caraguel, Charles; Rault, Jean-Loup

    2016-08-30

    Free range production systems are becoming a major source of egg production in Australia and worldwide. This study investigated shedding and ecology of Salmonella Typhimurium and Salmonella species in a free range layer flock, wild birds and foxes in the vicinity of the free range farm in different seasons. Shedding of Salmonella was significantly higher in summer. Within the shed, overall, Salmonella prevalence was highest in dust. Corticosterone level in faeces was highest in spring and lowest in winter. There was no direct association between the Salmonella shedding (MPN/gm) and corticosterone levels in faeces. Salmonella Typhimurium MLVA types isolated from fox and wild birds were similar to MLVA types isolated from layer flock and reported during human food borne illness. Wild birds and foxes appear to play an important role in S. Typhimurium ecology and food safety. Environmental factors could play a role in evolution of S. Typhimurium in free range environment. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

  11. Study on Method of Wide Dynamic Range Data Acquisition System

    NASA Astrophysics Data System (ADS)

    Hu, X.; Teng, Y.

    2013-12-01

    Seismic data acquisition system is an indispensable device for seismic signal digitalization processing. Its performance is directly related to the final seismic signal acquisited, and ultimately affect the results of the data processing. The amplitude of seismic signal has a great span, its dynamic range even reached more than 160dB. And the dynamic range of the output signal of broadband seismometer is greater than 150dB too. Yet the dynamic range of 24-bit DAS(Data Acquisition System) which is currently widespread used and based on Σ-ΔA/D converter is only about 130dB. This lead to that the small seismic signal can't be recorded by 24-bit DAS as well as the amplitude of big seismic event wave recorded by it would be limited. For instance, since the 2008 Wenchuan Ms8.0 Earthquake is a huge seismic event, the amplitudes of seismic wave recorded by all the 24-bit seismometors in Sichuan Province in China are seriously limited. It makes the earthquake monitoring station lost its function when we seriously need the data, and we lost the rare huge seismic event wave data for late studying. It is the requirement for the DAS in practical application that for a small seismic signal recorded, it needed to improve the signal-to-noise ratio and has a high resolution, and for a big one, it is demanded to record the signal perfectly and not to be limited of its amplitude. According to this, we present a new method of wide dynamic range data acquisition: The Analog-to-Digital Converter classifies the input signal amplitude into several levels; The smaller-amplitude-level input voltage signal is digitalized with higher resolution while lower resolution digitalized for the bigger-amplitude-level input; Every amplitude-level-signal can be digitalized by an independent ordinary 24-bit Σ-ΔA/D converter for its dynamic range is less smaller; And finally, the controller-processing unit make all the level signal digital outputs into a 32-bit data, which has high resolution and

  12. Advanced Range Safety System for High Energy Vehicles

    NASA Technical Reports Server (NTRS)

    Claxton, Jeffrey S.; Linton, Donald F.

    2002-01-01

    The advanced range safety system project is a collaboration between the National Aeronautics and Space Administration and the United States Air Force to develop systems that would reduce costs and schedule for safety approval for new classes of unmanned high-energy vehicles. The mission-planning feature for this system would yield flight profiles that satisfy the mission requirements for the user while providing an increased quality of risk assessment, enhancing public safety. By improving the speed and accuracy of predicting risks to the public, mission planners would be able to expand flight envelopes significantly. Once in place, this system is expected to offer the flexibility of handling real-time risk management for the high-energy capabilities of hypersonic vehicles including autonomous return-from-orbit vehicles and extended flight profiles over land. Users of this system would include mission planners of Space Launch Initiative vehicles, space planes, and other high-energy vehicles. The real-time features of the system could make extended flight of a malfunctioning vehicle possible, in lieu of an immediate terminate decision. With this improved capability, the user would have more time for anomaly resolution and potential recovery of a malfunctioning vehicle.

  13. Geoscience Laser Ranging System design and performance predictions

    NASA Technical Reports Server (NTRS)

    Anderson, Kent L.

    1991-01-01

    The Geoscience Laser System (GLRS) will be a high-precision distance-measuring instrument planned for deployment on the EOS-B platform. Its primary objectives are to perform ranging measurements to ground targets to monitor crustal deformation and tectonic plate motions, and nadir-looking altimetry to determine ice sheet thicknesses, surface topography, and vertical profiles of clouds and aerosols. The system uses a mode-locked, 3-color Nd:YAG laser source, a Microchannel Plate-PMT for absolute time-of-flight (TOF) measurement (at 532 nm), a streak camera for TOF 2-color dispersion measurement (532 nm and 355 nm), and a Si avalanche photodiode for altimeter waveform detection (1064 nm). The performance goals are to make ranging measurements to ground targets with about 1 cm accuracy, and altimetry height measurements over ice with 10 cm accuracy. This paper presents an overview of the design concept developed during a phase B study. System engineering issues and trade studies are discussed, with particular attention to error budgets and performance predictions.

  14. Error analysis for a spaceborne laser ranging system

    NASA Technical Reports Server (NTRS)

    Pavlis, E. C.

    1979-01-01

    The dependence (or independence) of baseline accuracies, obtained from a typical mission of a spaceborne ranging system, on several factors is investigated. The emphasis is placed on a priori station information, but factors such as the elevation cut-off angle, the geometry of the network, the mean orbital height, and to a limited extent geopotential modeling are also examined. The results are obtained through simulations, but some theoretical justification is also given. Guidelines for freeing the results from these dependencies are suggested for most of the factors.

  15. Coherent long-range thermoelectrics in nonadiabatic driven quantum systems

    NASA Astrophysics Data System (ADS)

    Gallego-Marcos, F.; Platero, G.

    2017-02-01

    We investigate direct energy and heat transfer between two distant sites of a triple quantum dot connected to reservoirs, where one of the edge dots is driven by an ac-gate voltage. We theoretically propose how to implement heat and cooling engines mediated by long-range photoassisted transport. Additionally, we propose a simple setup to heat up coherently the two reservoirs symmetrically and a mechanism to store energy in the closed system. The present proposals can be experimentally implemented and easily controlled by tuning the external parameters.

  16. Parallelized Stochastic Cutoff Method for Long-Range Interacting Systems

    NASA Astrophysics Data System (ADS)

    Endo, Eishin; Toga, Yuta; Sasaki, Munetaka

    2015-07-01

    We present a method of parallelizing the stochastic cutoff (SCO) method, which is a Monte-Carlo method for long-range interacting systems. After interactions are eliminated by the SCO method, we subdivide a lattice into noninteracting interpenetrating sublattices. This subdivision enables us to parallelize the Monte-Carlo calculation in the SCO method. Such subdivision is found by numerically solving the vertex coloring of a graph created by the SCO method. We use an algorithm proposed by Kuhn and Wattenhofer to solve the vertex coloring by parallel computation. This method was applied to a two-dimensional magnetic dipolar system on an L × L square lattice to examine its parallelization efficiency. The result showed that, in the case of L = 2304, the speed of computation increased about 102 times by parallel computation with 288 processors.

  17. Fractional dynamics of systems with long-range interaction

    NASA Astrophysics Data System (ADS)

    Tarasov, Vasily E.; Zaslavsky, George M.

    2006-12-01

    We consider one-dimensional chain of coupled linear and nonlinear oscillators with long-range powerwise interaction defined by a term proportional to 1/∣ n - m∣ α+1 . Continuous medium equation for this system can be obtained in the so-called infrared limit when the wave number tends to zero. We construct a transform operator that maps the system of large number of ordinary differential equations of motion of the particles into a partial differential equation with the Riesz fractional derivative of order α, when 0 < α < 2. Few models of coupled oscillators are considered and their synchronized states and localized structures are discussed in details. Particularly, we discuss some solutions of time-dependent fractional Ginzburg-Landau (or nonlinear Schrodinger) equation.

  18. Measuring Systems for Thermometer Calibration in Low-Temperature Range

    NASA Astrophysics Data System (ADS)

    Szmyrka-Grzebyk, A.; Lipiński, L.; Manuszkiewicz, H.; Kowal, A.; Grykałowska, A.; Jancewicz, D.

    2011-12-01

    The national temperature standard for the low-temperature range between 13.8033 K and 273.16 K has been established in Poland at the Institute of Low Temperature and Structure Research (INTiBS). The standard consists of sealed cells for realization of six fixed points of the International Temperature Scale of 1990 (ITS-90) in the low-temperature range, an adiabatic cryostat and Isotech water and mercury triple-point baths, capsule standard resistance thermometers (CSPRT), and AC and DC bridges with standard resistors for thermometers resistance measurements. INTiBS calibrates CSPRTs at the low-temperature fixed points with uncertainties less than 1 mK. In lower temperature range—between 2.5 K and about 25 K — rhodium-iron (RhFe) resistance thermometers are calibrated by comparison with a standard which participated in the EURAMET.T-K1.1 comparison. INTiBS offers a calibration service for industrial platinum resistance thermometers and for digital thermometers between 77 K and 273 K. These types of thermometers may be calibrated at INTiBS also in a higher temperature range up to 550°C. The Laboratory of Temperature Standard at INTiBS acquired an accreditation from the Polish Centre for Accreditation. A management system according to EN ISO/IEC 17025:2005 was established at the Laboratory and presented on EURAMET QSM Forum.

  19. Airborne laser ranging system for monitoring regional crustal deformation

    NASA Technical Reports Server (NTRS)

    Degnan, J. J.

    1981-01-01

    Alternate approaches for making the atmospheric correction without benefit of a ground-based meteorological network are discussed. These include (1) a two-color channel that determines the atmospheric correction by measuring the time delay induced by dispersion between pulses at two optical frequencies; (2) single-color range measurements supported by an onboard temperature sounder, pressure altimeter readings, and surface measurements by a few existing meteorological facilities; and (3) inclusion of the quadratic polynomial coefficients as variables to be solved for along with target coordinates in the reduction of the single-color range data. It is anticipated that the initial Airborne Laser Ranging System (ALRS) experiments will be carried out in Southern California in a region bounded by Santa Barbara on the norht and the Mexican border on the south. The target area will be bounded by the Pacific Ocean to the west and will extend eastward for approximately 400 km. The unique ability of the ALRS to provide a geodetic 'snapshot' of such a large area will make it a valuable geophysical tool.

  20. Performance Analysis of the Spaceborne Laser Ranging System

    NASA Technical Reports Server (NTRS)

    Kahn, W. D.; Vonbun, F. O.; Smith, D. E.; Englar, T. S.; Gibbs, B. P.

    1979-01-01

    The 'spaceborne laser ranging system' is a proposed short pulse laser on board an orbiting spacecraft. It measures the distances between the spacecraft and many laser retroreflectors (targets) deployed on the earth's surface. The precision of these range measurements was assumed to be about plus or minus 2 cm. These measurements were then used together with the orbital dynamics of the spacecraft to derive the intersite vector between the laser ground targets. The errors associated with this vector were on the order of 1 to 2 cm. The baseline distances determined range from 25 km to 1200 km. By repeating the measurements of the intersite vector, strain and strain rate errors were estimated. The realizable precision for intersite distance determination was estimated to be on the order of 0.5 cm at 300 km and about 1.5 cm at 1200 km. The corresponding inaccuracies for the intersite distances were larger, than is 1 cm and 3.5 cm respectively. The corresponding precision in the vertical direction was 1 cm and 3 cm.

  1. Detecting Topological Defect Dark Matter Using Coherent Laser Ranging System

    NASA Astrophysics Data System (ADS)

    Yang, Wanpeng; Leng, Jianxiao; Zhang, Shuangyou; Zhao, Jianye

    2016-07-01

    In the last few decades, optical frequency combs with high intensity, broad optical bandwidth, and directly traceable discrete wavelengths have triggered rapid developments in distance metrology. However, optical frequency combs to date have been limited to determine the absolute distance to an object (such as satellite missions). We propose a scheme for the detection of topological defect dark matter using a coherent laser ranging system composed of dual-combs and an optical clock via nongravitational signatures. The dark matter field, which comprises a defect, may interact with standard model particles, including quarks and photons, resulting in the alteration of their masses. Thus, a topological defect may function as a dielectric material with a distinctive frequency-depend index of refraction, which would cause the time delay of a periodic extraterrestrial or terrestrial light. When a topological defect passes through the Earth, the optical path of long-distance vacuum path is altered, this change in optical path can be detected through the coherent laser ranging system. Compared to continuous wavelength(cw) laser interferometry methods, dual-comb interferometry in our scheme excludes systematic misjudgement by measuring the absolute optical path length.

  2. Detecting Topological Defect Dark Matter Using Coherent Laser Ranging System.

    PubMed

    Yang, Wanpeng; Leng, Jianxiao; Zhang, Shuangyou; Zhao, Jianye

    2016-07-08

    In the last few decades, optical frequency combs with high intensity, broad optical bandwidth, and directly traceable discrete wavelengths have triggered rapid developments in distance metrology. However, optical frequency combs to date have been limited to determine the absolute distance to an object (such as satellite missions). We propose a scheme for the detection of topological defect dark matter using a coherent laser ranging system composed of dual-combs and an optical clock via nongravitational signatures. The dark matter field, which comprises a defect, may interact with standard model particles, including quarks and photons, resulting in the alteration of their masses. Thus, a topological defect may function as a dielectric material with a distinctive frequency-depend index of refraction, which would cause the time delay of a periodic extraterrestrial or terrestrial light. When a topological defect passes through the Earth, the optical path of long-distance vacuum path is altered, this change in optical path can be detected through the coherent laser ranging system. Compared to continuous wavelength(cw) laser interferometry methods, dual-comb interferometry in our scheme excludes systematic misjudgement by measuring the absolute optical path length.

  3. Detecting Topological Defect Dark Matter Using Coherent Laser Ranging System

    PubMed Central

    Yang, Wanpeng; Leng, Jianxiao; Zhang, Shuangyou; Zhao, Jianye

    2016-01-01

    In the last few decades, optical frequency combs with high intensity, broad optical bandwidth, and directly traceable discrete wavelengths have triggered rapid developments in distance metrology. However, optical frequency combs to date have been limited to determine the absolute distance to an object (such as satellite missions). We propose a scheme for the detection of topological defect dark matter using a coherent laser ranging system composed of dual-combs and an optical clock via nongravitational signatures. The dark matter field, which comprises a defect, may interact with standard model particles, including quarks and photons, resulting in the alteration of their masses. Thus, a topological defect may function as a dielectric material with a distinctive frequency-depend index of refraction, which would cause the time delay of a periodic extraterrestrial or terrestrial light. When a topological defect passes through the Earth, the optical path of long-distance vacuum path is altered, this change in optical path can be detected through the coherent laser ranging system. Compared to continuous wavelength(cw) laser interferometry methods, dual-comb interferometry in our scheme excludes systematic misjudgement by measuring the absolute optical path length. PMID:27389642

  4. Short range spread-spectrum radiolocation system and method

    DOEpatents

    Smith, Stephen F.

    2003-04-29

    A short range radiolocation system and associated methods that allow the location of an item, such as equipment, containers, pallets, vehicles, or personnel, within a defined area. A small, battery powered, self-contained tag is provided to an item to be located. The tag includes a spread-spectrum transmitter that transmits a spread-spectrum code and identification information. A plurality of receivers positioned about the area receive signals from a transmitting tag. The position of the tag, and hence the item, is located by triangulation. The system employs three different ranging techniques for providing coarse, intermediate, and fine spatial position resolution. Coarse positioning information is provided by use of direct-sequence code phase transmitted as a spread-spectrum signal. Intermediate positioning information is provided by the use of a difference signal transmitted with the direct-sequence spread-spectrum code. Fine positioning information is provided by use of carrier phase measurements. An algorithm is employed to combine the three data sets to provide accurate location measurements.

  5. Classical investigation of long-range coherence in biological systems

    NASA Astrophysics Data System (ADS)

    Preto, Jordane

    2016-12-01

    Almost five decades ago, H. Fröhlich [H. Fröhlich, "Long-range coherence and energy storage in biological systems," Int. J. Quantum Chem. 2(5), 641-649 (1968)] reported, on a theoretical basis, that the excitation of quantum modes of vibration in contact with a thermal reservoir may lead to steady states, where under high enough rate of energy supply, only specific low-frequency modes of vibration are strongly excited. This nonlinear phenomenon was predicted to occur in biomolecular systems, which are known to exhibit complex vibrational spectral properties, especially in the terahertz frequency domain. However, since the effects of terahertz or lower-frequency modes are mainly classical at physiological temperatures, there are serious doubts that Fröhlich's quantum description can be applied to predict such a coherent behavior in a biological environment, as suggested by the author. In addition, a quantum formalism makes the phenomenon hard to investigate using realistic molecular dynamics simulations (MD) as they are usually based on the classical principles. In the current paper, we provide a general classical Hamiltonian description of a nonlinear open system composed of many degrees of freedom (biomolecular structure) excited by an external energy source. It is shown that a coherent behaviour similar to Fröhlich's effect is to be expected in the classical case for a given range of parameter values. Thus, the supplied energy is not completely thermalized but stored in a highly ordered fashion. The connection between our Hamiltonian description, carried out in the space of normal modes, and a more standard treatment in the physical space is emphasized in order to facilitate the prediction of the effect from MD simulations. It is shown how such a coherent phenomenon may induce long-range resonance effects that could be of critical importance at the biomolecular level. The present work is motivated by recent experimental evidences of long-lived excited low

  6. Classical investigation of long-range coherence in biological systems.

    PubMed

    Preto, Jordane

    2016-12-01

    Almost five decades ago, H. Fröhlich [H. Fröhlich, "Long-range coherence and energy storage in biological systems," Int. J. Quantum Chem. 2(5), 641-649 (1968)] reported, on a theoretical basis, that the excitation of quantum modes of vibration in contact with a thermal reservoir may lead to steady states, where under high enough rate of energy supply, only specific low-frequency modes of vibration are strongly excited. This nonlinear phenomenon was predicted to occur in biomolecular systems, which are known to exhibit complex vibrational spectral properties, especially in the terahertz frequency domain. However, since the effects of terahertz or lower-frequency modes are mainly classical at physiological temperatures, there are serious doubts that Fröhlich's quantum description can be applied to predict such a coherent behavior in a biological environment, as suggested by the author. In addition, a quantum formalism makes the phenomenon hard to investigate using realistic molecular dynamics simulations (MD) as they are usually based on the classical principles. In the current paper, we provide a general classical Hamiltonian description of a nonlinear open system composed of many degrees of freedom (biomolecular structure) excited by an external energy source. It is shown that a coherent behaviour similar to Fröhlich's effect is to be expected in the classical case for a given range of parameter values. Thus, the supplied energy is not completely thermalized but stored in a highly ordered fashion. The connection between our Hamiltonian description, carried out in the space of normal modes, and a more standard treatment in the physical space is emphasized in order to facilitate the prediction of the effect from MD simulations. It is shown how such a coherent phenomenon may induce long-range resonance effects that could be of critical importance at the biomolecular level. The present work is motivated by recent experimental evidences of long-lived excited low

  7. Nd:YAG development for spaceborne laser ranging system

    NASA Technical Reports Server (NTRS)

    Harper, L. L.; Logan, K. E.; Williams, R. H.; Stevens, D. A.

    1979-01-01

    The results of the development of a unique modelocked laser device to be utilized in future NASA space-based, ultraprecision laser ranger systems are summarized. The engineering breadboard constructed proved the feasibility of the pump-pulsed, actively modelocked, PTM Q-switched Nd:YAG laser concept for the generation of subnanosecond pulses suitable for ultra-precision ranging. The laser breadboard also included a double-pass Nd:YAG amplifier and provision for a Type II KD*P frequency doubler. The specific technical accomplishment was the generation of single 150 psec, 20-mJ pulses at 10 pps at a wavelength of 1.064 micrometers with 25 dB suppression of pre-and post-pulses.

  8. A magnetic suspension system with a large angular range

    NASA Technical Reports Server (NTRS)

    Britcher, Colin P.; Ghofrani, Mehran

    1993-01-01

    The paper describes a small-scale laboratory system, called the Large-Angle Magnetic Suspension Test Fixture (LAMSTF), constructed at NASA Langley Research Center in order to explore and develop technology required for the magnetic suspension of objects over large ranges of orientation. The LAMSTF hardware comprises five electromagnets in a circular arrangement, each driven from a separate bipolar power amplifier. The suspended element is a cylindrical axially magnetized permanent magnet core, within an aluminum tube. The element, which is 'levitated' by repulsive forces, is stabilized in five degrees-of-freedom, with rotation about the cylinder axis not controlled. The controller accommodates the changes in magnetic coupling between the electromagnets and the suspended element by real-time adaptation of a decoupling matrix. The paper presents performance measurements demonstrating that the major design objective of the 360 deg rotation was accomplished.

  9. Dentin Conditioning with Bioactive Molecule Releasing Nanoparticle System Enhances Adherence, Viability, and Differentiation of Stem Cells from Apical Papilla.

    PubMed

    Shrestha, Suja; Torneck, Calvin D; Kishen, Anil

    2016-05-01

    Temporal-controlled bioactive molecule (BM) releasing systems allow the delivery of appropriate concentration of BM to enhance the interaction of stem cells to dentin matrix and subsequent odontogenic differentiation in regenerative endodontics. The goal of this study was to evaluate the effect of dentin conditioning with 2 variants of dexamethasone (Dex) releasing chitosan nanoparticles (CSnp), (1) Dex-CSnpI (slow releasing) and (2) Dex-CSnpII (rapid releasing), on adherence, viability, and differentiation of stem cells from apical papilla (SCAP) on root dentin exposed to endodontic irrigants. Slab-shaped dentin specimens were prepared parallel to the root canal and treated with 5.25% sodium hypochlorite (NaOCl) for 10 minutes and/or 17% EDTA for 2 minutes. Dentin was then conditioned accordingly by (1) no nanoparticle treatment, (2) CSnp, (3) Dex-CSnpI, and (4) Dex-CSnpII. The effect of nanoparticle conditioning on SCAP viability was determined by cell count and a circularity index. SCAP adherence and viability on dentin were assessed by fluorescence and scanning electron microscopy and odontogenic differentiation by immunofluorescence. SCAP on dentin treated with NaOCl alone or NaOCl as the last irrigant showed the least adherence, minimal cytoplasmic extensions, and higher circularity. SCAP adherence and viability on Dex-CSnpI and Dex-CSnpII conditioned dentin were increased and had a well-developed cytoplasmic matrix and significantly lower circularity (P < .05). SCAP cultured in Dex-CSnpII group expressed higher levels for DSPP and DMP-1 than in CSnp or Dex-CSnpI groups. Dex-CSnpI and Dex-CSnpII conditioning of dentin enhanced SCAP adherence and viability. Temporal-controlled release of Dex from Dex-CSnpII enhanced odontogenic differentiation of SCAP. This study highlighted the ability of dentin conditioning with temporal-controlled BM releasing nanoparticles to improve the local environment in regenerative endodontics. Copyright © 2016 American

  10. Combination of Fluorescence In Situ Hybridization with Staining Techniques for Cell Viability and Accumulation of PHA and polyP in Microorganisms in Complex Microbial Systems

    NASA Astrophysics Data System (ADS)

    Nielsen, Jeppe Lund; Kragelund, Caroline; Nielsen, Per Halkjær

    Fluorescence in situ hybridization (FISH) can be combined with a number of staining techniques to reveal the relationships between the microorganisms and their function in complex microbial systems with a single-cell resolution. In this chapter, we have focused on staining methods for intracellular storage compounds (polyhydroxyalkanoates, polyphosphate) and a measure for cell viability, reduction of the tetrazolium-based redox stain CTC. These protocols are optimized for the study of microorganisms in waste-water treatment (activated sludge and biofilms), but they may also be used with minor modifications in many other ecosystems.

  11. Wide tracking range, auto ranging, low jitter phase lock loop for swept and fixed frequency systems

    DOEpatents

    Kerner, Thomas M.

    2001-01-01

    The present invention provides a wide tracking range phase locked loop (PLL) circuit that achieves minimal jitter in a recovered clock signal, regardless of the source of the jitter (i.e. whether it is in the source or the transmission media). The present invention PLL has automatic harmonic lockout detection circuitry via a novel lock and seek control logic in electrical communication with a programmable frequency discriminator and a code balance detector. (The frequency discriminator enables preset of a frequency window of upper and lower frequency limits to derive a programmable range within which signal acquisition is effected. The discriminator works in combination with the code balance detector circuit to minimize the sensitivity of the PLL circuit to random data in the data stream). In addition, the combination of a differential loop integrator with the lock and seek control logic obviates a code preamble and guarantees signal acquisition without harmonic lockup. An adaptive cable equalizer is desirably used in combination with the present invention PLL to recover encoded transmissions containing a clock and/or data. The equalizer automatically adapts to equalize short haul cable lengths of coaxial and twisted pair cables or wires and provides superior jitter performance itself. The combination of the equalizer with the present invention PLL is desirable in that such combination permits the use of short haul wires without significant jitter.

  12. Screening of Electric field in a Variable Range Hopping System

    NASA Astrophysics Data System (ADS)

    Prigodin, Vladimir; Epstein, Arthur

    2003-03-01

    Recent report of a field effect in conducting polymers [1] initiated a large interest. The "field effect" can not be explained only by electrochemical dedoping of polymers. Also the field effect is impossible to understand within a model of homogeneous conductor because of the atomic scale of Debye radius. We discuss the penetration of electric field in a system in which charge transport is provided by variable range hopping (VRH). The majority of carriers are localized and contribute to the dielectric constant. An exponentially small fraction of carriers are mobile and screens the external field. Our estimate shows that the screening length for conducting polymers can be essentially larger than in metals but is still not enough to explain the experimental data. A combination of different factors including the inhomogeneous (granular) structure of conducting polymers may control the observable phenomena. J. Lu et al., J. Appl. Phys. XX, in press (2002); A.J. Epstein et al., Current Appl. Lett. 2, 339 (2002); M. Ishihara and H. Okuzaki, Synth. Met. XX, in press (2003).

  13. Performance of the upgraded Orroral laser ranging system

    NASA Technical Reports Server (NTRS)

    Luck, John M.

    1993-01-01

    The topics discussed include the following: upgrade arrangements, system prior to 1991, elements of the upgrade, laser performance, timing system performance, pass productivity, system precision, system accuracy, telescope pointing and future upgrades and extensions.

  14. Quantum many-body systems with short-range interactions

    NASA Astrophysics Data System (ADS)

    Yin, Jun

    In this dissertation, the central theme is evaluation of the ground energy and the first few excited energies of Bose or Fermi gas system in continuum R3 or lattice Z3 with short-range interactions. In Chapter 2 and 3, we carry out an analysis on low-dimensional behaviors of dilute Bose gas in traps. In Chapter 4 and 5, we generalize the results on the ground state energies of dilute Bose or Fermi gases in thermodynamic limit. In quantum mechanics, many-body quantum system is completely described by the Hamiltonian, which is a self-adjoint operator on a suitable Hilbert space. In proper scaling limits and parameter regimes, these three-dimensional Hamiltonians can be rigorously described by effective low-dimensional Hamiltonians or equations. In Chapter 2 we show that the Lieb-Liniger model for one-dimensional bosons with repulsive Delta function interaction can be rigorously derived from a dilute three-dimensional Bose gas with arbitrary repulsive interaction potential of finite scattering length. In Chapter 3 we prove that the two dimensional rotating Gross-Pitaevskii (GP) equation correctly describes the ground state energy and corresponding one-particle density matrix of rotating, dilute, interacting Bose gas in three dimensions in a potential that is strongly confining in one direction. Another one of the most remarkable recent developments in study of dilute Bose gases is the rigorous proofs on the leading terms of the effect of the repulsive interaction potential on the ground state energy or the free energy in the thermodynamic limit. For interacting Bose gases, in [44], Lieb and Yngvason proved the correction per volume on ground energy is 4pi aϱ2, where a is the scattering length of interaction potential and ϱ is the density. In this dissertation we generalize this result as follows, we prove that the upper bound part holds for all interaction potentials of positive scattering length, i.e., a > 0, and the lower bound part holds for some interaction

  15. Bioluminescence assay for cell viability.

    PubMed

    Lomakina, G Yu; Modestova, Yu A; Ugarova, N N

    2015-06-01

    Theoretical aspects of the adenosine triphosphate bioluminescence assay based on the use of the firefly luciferin-luciferase system are considered, as well as its application for assessing cell viability in microbiology, sanitation, medicine, and ecology. Various approaches for the analysis of individual or mixed cultures of microorganisms are presented, and capabilities of the method for investigation of biological processes in live cells including necrosis, apoptosis, as well as for investigation of the dynamics of metabolism are described.

  16. Improvement of range precision in laser detection and ranging system by using two Geiger mode avalanche photodiodes.

    PubMed

    Kim, Tae Hoon; Kong, Hong Jin; Jo, Sung Eun; Jeon, Byoung Goo; Oh, Min Seok; Heo, Ayoung; Park, Dong Jo

    2013-06-01

    In this paper, the improvement of range precision in a laser detection and ranging (LADAR) system by using two Geiger mode avalanche photodiodes (GmAPDs) is described. The LADAR system is implemented by using two GmAPDs with a beam splitter and applying comparative process to their ends. Then, the timing circuit receives the electrical signals only if each GmAPDs generates electrical signals simultaneously. Though this system decreases the energy of a laser-return pulse scattered from the target, it is effective in reducing the range precision. The experimental results showed that the average value of standard deviation of time of flights was improved from 61 mm to 37 mm when the pulse energy is 0.6 μJ. When the time bin width is 0.5 ns, the single-shot precision error of the LADAR system was also improved from 280 mm to 67 mm.

  17. Improvement of range precision in laser detection and ranging system by using two Geiger mode avalanche photodiodes

    NASA Astrophysics Data System (ADS)

    Kim, Tae Hoon; Kong, Hong Jin; Jo, Sung Eun; Jeon, Byoung Goo; Oh, Min Seok; Heo, Ayoung; Park, Dong Jo

    2013-06-01

    In this paper, the improvement of range precision in a laser detection and ranging (LADAR) system by using two Geiger mode avalanche photodiodes (GmAPDs) is described. The LADAR system is implemented by using two GmAPDs with a beam splitter and applying comparative process to their ends. Then, the timing circuit receives the electrical signals only if each GmAPDs generates electrical signals simultaneously. Though this system decreases the energy of a laser-return pulse scattered from the target, it is effective in reducing the range precision. The experimental results showed that the average value of standard deviation of time of flights was improved from 61 mm to 37 mm when the pulse energy is 0.6 μJ. When the time bin width is 0.5 ns, the single-shot precision error of the LADAR system was also improved from 280 mm to 67 mm.

  18. Challenge testing the lactoperoxidase system against a range of bacteria using different activation agents.

    PubMed

    Fweja, L W T; Lewis, M J; Grandison, A S

    2008-07-01

    Lactoperoxidase (LP) exerts antimicrobial effects in combination with H(2)O(2) and either thiocyanate (SCN(-)) or a halide (e.g., I(-)). Garlic extract in the presence of ethanol has also been used to activate the LP system. This study aimed to determine the effects of 3 LP activation systems (LP+SCN(-)+H(2)O(2); LP+I(-)+H(2)O(2); LP + garlic extract + ethanol) on the growth and activity of 3 test organisms (Staphylococcus aureus, Pseudomonas aeruginosa, and Bacillus cereus). Sterilized milk was used as the reaction medium, and the growth pattern of the organisms and a range of keeping quality (KQ) indicators (pH, titratable acidity, ethanol stability, clot on boiling) were monitored during storage at the respective optimum growth temperature for each organism. The LP+I(-)+ H(2)O(2) system reduced bacterial counts below the detection limit shortly after treatment for all 3 organisms, and no bacteria could be detected for the duration of the experiment (35 to 55 h). The KQ data confirmed that the milk remained unspoiled at the end of the experiments. The LP + garlic extract + ethanol system, on the other hand, had no effect on the growth or KQ with P. aeruginosa, but showed a small retardation of growth of the other 2 organisms, accompanied by small increases (5 to 10 h) in KQ. The effects of the LP+SCN(-)+H(2)O(2) system were intermediate between those of the other 2 systems and differed between organisms. With P. aeruginosa, the system exerted total inhibition within 10 h of incubation, but the bacteria regained viability after a further 5 h, following a logarithmic growth curve. This was reflected in the KQ indicators, which implied an extension of 15 h. With the other 2 bacterial species, LP+SCN(-)+H(2)O(2) exerted an obvious inhibitory effect, giving a lag phase in the growth curve of 5 to 10 h and KQ extension of 10 to 15 h. When used in combination, I(-) and SCN(-) displayed negative synergy.

  19. Denver RTD range extension study. Task 2 - system definitions. Task 3 - system assessments. Working paper

    SciTech Connect

    Not Available

    1982-05-01

    This working paper presents the results obtained in Task 2: System Definition and Task 3: System Assessments of the Battery-Electric Bus Range Extension Study of the Denver Regional Transit District (RTD) study. The buses were tested on the following range extension techniques: baseline system battery exchange; hydro-pneumatic regeneration system to recover braking energy; fast recharge at the Mall terminals; series hybrid: on-board internal combustion engine and generator which charges the battery; and combination of hydro-pneumatic regeneration and fast recharge at the Mall terminals.

  20. Communication system features dual mode range acquisition plus time delay measurement

    NASA Technical Reports Server (NTRS)

    Atwood, S. W.; Kline, A. W., Jr.; Welter, N. E.

    1968-01-01

    Communication system combines range acquisition system and time measurement system for tracking high velocity aircraft and spacecraft. The range acquisition system uses a pseudonoise code to determine range and the time measurement system reduces uncontrolled phase variations in the demodulated signal.

  1. Fusion of a Variable Baseline System and a Range Finder

    PubMed Central

    Hernández-Aceituno, Javier; Acosta, Leopoldo; Arnay, Rafael

    2012-01-01

    One of the greatest difficulties in stereo vision is the appearance of ambiguities when matching similar points from different images. In this article we analyze the effectiveness of using a fusion of multiple baselines and a range finder from a theoretical point of view, focusing on the results of using both prismatic and rotational articulations for baseline generation, and offer a practical case to prove its efficiency on an autonomous vehicle. PMID:22368469

  2. Range Safety for an Autonomous Flight Safety System

    NASA Technical Reports Server (NTRS)

    Lanzi, Raymond J.; Simpson, James C.

    2010-01-01

    The Range Safety Algorithm software encapsulates the various constructs and algorithms required to accomplish Time Space Position Information (TSPI) data management from multiple tracking sources, autonomous mission mode detection and management, and flight-termination mission rule evaluation. The software evaluates various user-configurable rule sets that govern the qualification of TSPI data sources, provides a prelaunch autonomous hold-launch function, performs the flight-monitoring-and-termination functions, and performs end-of-mission safing

  3. Noise pair velocity and range echo location system

    DOEpatents

    Erskine, David J.

    1999-01-01

    An echo-location method for microwaves, sound and light capable of using incoherent and arbitrary waveforms of wide bandwidth to measure velocity and range (and target size) simultaneously to high resolution. Two interferometers having very long and nearly equal delays are used in series with the target interposed. The delays can be longer than the target range of interest. The first interferometer imprints a partial coherence on an initially incoherent source which allows autocorrelation to be performed on the reflected signal to determine velocity. A coherent cross-correlation subsequent to the second interferometer with the source determines a velocity discriminated range. Dithering the second interferometer identifies portions of the cross-correlation belonging to a target apart from clutter moving at a different velocity. The velocity discrimination is insensitive to all slowly varying distortions in the signal path. Speckle in the image of target and antenna lobing due to parasitic reflections is minimal for an incoherent source. An arbitrary source which varies its spectrum dramatically and randomly from pulse to pulse creates a radar elusive to jamming. Monochromatic sources which jigger in frequency from pulse to pulse or combinations of monochromatic sources can simulate some benefits of incoherent broadband sources. Clutter which has a symmetrical velocity spectrum will self-cancel for short wavelengths, such as the apparent motion of ground surrounding target from a sidelooking airborne antenna.

  4. Noise pair velocity and range echo location system

    DOEpatents

    Erskine, D.J.

    1999-02-16

    An echo-location method for microwaves, sound and light capable of using incoherent and arbitrary waveforms of wide bandwidth to measure velocity and range (and target size) simultaneously to high resolution is disclosed. Two interferometers having very long and nearly equal delays are used in series with the target interposed. The delays can be longer than the target range of interest. The first interferometer imprints a partial coherence on an initially incoherent source which allows autocorrelation to be performed on the reflected signal to determine velocity. A coherent cross-correlation subsequent to the second interferometer with the source determines a velocity discriminated range. Dithering the second interferometer identifies portions of the cross-correlation belonging to a target apart from clutter moving at a different velocity. The velocity discrimination is insensitive to all slowly varying distortions in the signal path. Speckle in the image of target and antenna lobing due to parasitic reflections is minimal for an incoherent source. An arbitrary source which varies its spectrum dramatically and randomly from pulse to pulse creates a radar elusive to jamming. Monochromatic sources which jigger in frequency from pulse to pulse or combinations of monochromatic sources can simulate some benefits of incoherent broadband sources. Clutter which has a symmetrical velocity spectrum will self-cancel for short wavelengths, such as the apparent motion of ground surrounding target from a sidelooking airborne antenna. 46 figs.

  5. Structure, stability, and formation pathways of colloidal gels in systems with short-range attraction and long-range repulsion.

    PubMed

    van Schooneveld, Matti M; de Villeneuve, Volkert W A; Dullens, Roel P A; Aarts, Dirk G A L; Leunissen, Mirjam E; Kegel, Willem K

    2009-04-09

    We study colloidal gels formed upon centrifugation of dilute suspensions of spherical colloids (radius 446 nm) that interact through a long-range electrostatic repulsion (Debye length approximately 850 nm) and a short-range depletion attraction (approximately 12.5 nm), by means of confocal scanning laser microscopy (CSLM). In these systems, at low colloid densities, colloidal clusters are stable. Upon increasing the density by centrifugation, at different stages of cluster formation, we show that colloidal gels are formed that significantly differ in structure. While significant single-particle displacements do not occur on the hour time scale, the different gels slowly evolve within several weeks to a similar structure that is at least stable for over a year. Furthermore, while reference systems without long-range repulsion collapse into dense glassy states, the repulsive colloidal gels are able to support external stress in the form of a centrifugal field of at least 9g.

  6. Artificial evolution by viability rather than competition.

    PubMed

    Maesani, Andrea; Fernando, Pradeep Ruben; Floreano, Dario

    2014-01-01

    Evolutionary algorithms are widespread heuristic methods inspired by natural evolution to solve difficult problems for which analytical approaches are not suitable. In many domains experimenters are not only interested in discovering optimal solutions, but also in finding the largest number of different solutions satisfying minimal requirements. However, the formulation of an effective performance measure describing these requirements, also known as fitness function, represents a major challenge. The difficulty of combining and weighting multiple problem objectives and constraints of possibly varying nature and scale into a single fitness function often leads to unsatisfactory solutions. Furthermore, selective reproduction of the fittest solutions, which is inspired by competition-based selection in nature, leads to loss of diversity within the evolving population and premature convergence of the algorithm, hindering the discovery of many different solutions. Here we present an alternative abstraction of artificial evolution, which does not require the formulation of a composite fitness function. Inspired from viability theory in dynamical systems, natural evolution and ethology, the proposed method puts emphasis on the elimination of individuals that do not meet a set of changing criteria, which are defined on the problem objectives and constraints. Experimental results show that the proposed method maintains higher diversity in the evolving population and generates more unique solutions when compared to classical competition-based evolutionary algorithms. Our findings suggest that incorporating viability principles into evolutionary algorithms can significantly improve the applicability and effectiveness of evolutionary methods to numerous complex problems of science and engineering, ranging from protein structure prediction to aircraft wing design.

  7. Multiple-Station Range Target System Operations Manual

    DTIC Science & Technology

    1992-09-01

    Ju:tif Let i OIL- S... .. 4’ * .* - t NOTICES FINAL DISPOSITION: This Research Product may be destroyed when it is no longer needed. Please do not return...reoor.--t) rc .e" fc~imtai 3ectionof ilnlorrmator cv stmatec to aefage Tfhour cer resaarse, including Mce time for reviewina instructicrts. searz"-C4! es1...the following team leader events is provided in terms of target range and elapsed time : detection, identification, and command to engage or cease

  8. Heart rate, multiple body temperature, long-range and long-life telemetry system for free-ranging animals

    NASA Technical Reports Server (NTRS)

    Lund, G. F.; Westbrook, R. M.; Fryer, T. B.

    1980-01-01

    The design details and rationale for a versatile, long-range, long-life telemetry data acquisition system for heart rates and body temperatures at multiple locations from free-ranging animals are presented. The design comprises an implantable transmitter for short to medium range transmission, a receiver retransmitter collar to be worn for long-range transmission, and a signal conditioner interface circuit to assist in signal discrimination and demodulation of receiver or tape-recorded audio outputs. Implanted electrodes are used to obtain an ECG, from which R-wave characteristics are selected to trigger a short RF pulse. Pulses carrying heart rate information are interrupted periodically by a series of pulse interval modulated RF pulses conveying temperature information sensed at desired locations by thermistors. Pulse duration and pulse sequencing are used to discriminate between heart rate and temperature pulses as well as radio frequency interference. The implanted transmitter may be used alone for medium and short-range tracking, or with a receiver-transmitter collar that employs commercial tracking equipment for transmissions of up to 12 km. A system prototype has been tested on a dog.

  9. Heart rate, multiple body temperature, long-range and long-life telemetry system for free-ranging animals

    NASA Technical Reports Server (NTRS)

    Lund, G. F.; Westbrook, R. M.; Fryer, T. B.

    1980-01-01

    The design details and rationale for a versatile, long-range, long-life telemetry data acquisition system for heart rates and body temperatures at multiple locations from free-ranging animals are presented. The design comprises an implantable transmitter for short to medium range transmission, a receiver retransmitter collar to be worn for long-range transmission, and a signal conditioner interface circuit to assist in signal discrimination and demodulation of receiver or tape-recorded audio outputs. Implanted electrodes are used to obtain an ECG, from which R-wave characteristics are selected to trigger a short RF pulse. Pulses carrying heart rate information are interrupted periodically by a series of pulse interval modulated RF pulses conveying temperature information sensed at desired locations by thermistors. Pulse duration and pulse sequencing are used to discriminate between heart rate and temperature pulses as well as radio frequency interference. The implanted transmitter may be used alone for medium and short-range tracking, or with a receiver-transmitter collar that employs commercial tracking equipment for transmissions of up to 12 km. A system prototype has been tested on a dog.

  10. Unmanned Aerial Vehicles. Medium Range System Components do not Fit

    DTIC Science & Technology

    1991-03-01

    enemy activities and identification of targets. uAv systems typically include an air vehicle, a Page 1 GAO/NSIAW.91-2 Unmanned Aerial Vehicles 91 4 15 026...the current system’s existing problems. -’-- Page 3 GAO/NSTAD-91-2 Unmanned Aerial Vehicles B-242779 Recommendations We recommend that the Secretary...representative is still not a member of the KIAIzS configuration control board. Page 4 GAO/NSIAD-91-2 Unmanned Aerial Vehicles B-242779 We continue to believe

  11. Wurtzite Zn1-y(MgxCd1-x)yO quaternary systems for photodiodes in visible spectral range

    NASA Astrophysics Data System (ADS)

    Nieda, Yoshiaki; Suzuki, Mari; Nakamura, Atsushi; Temmyo, Jiro; Tabares, Gema; Kurtz, Alejandro; Lopez, Manuel; Ulloa, José María; Hierro, Adrian; Muñoz, Elías

    2016-09-01

    We investigated the optical bandgap engineering of ZnO based quaternary alloy films of wurtzite Zn1-y(MgxCd1-x)yO for photodiodes in visible spectral range. Quaternary alloy films were successfully synthesized by remote-plasma enhanced metalorganic chemical vapor deposition (RPE-MOCVD). The wurtzite alloy system has an optical bandgap energy between 2.16 eV and 3.25 eV, which was controlled by the flow ratio of metalorganic sources. The crystal structure and composition was analyzed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). This revealed that carrier compensation effects by alloying with MgO in Zn1-xCdxO system decreases carrier concentration. Strong compensation effects were observed in the bandgap range of Zn1-y(MgxCd1-x)yO between 3.0 eV to 3.25 eV and the carrier concentration decreased to 1015-1018 cm-3. Schottky diodes of PEDOT: PSS/Zn1-y(MgxCd1-y)yO with optical bandgaps in the visible spectral range were fabricated to confirm the viability of photovoltaic applications. The diodes performed photovoltaic characteristics under a Xe-Hg lamp illumination through Schottky junctions. The photoresponse spectra showed a photosensitivity with cutoff energy of 2.23 eV and peak energy of 2.90 eV at 0 V biasing.

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

    NASA Technical Reports Server (NTRS)

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

    1995-01-01

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

  13. Television-and-Laser Range-Measuring System

    NASA Technical Reports Server (NTRS)

    Russell, J. Kevin

    1988-01-01

    Triangulation system measures angle between two lines of sight to point on object, determining distance to object. Amenable to automation. Includes automatically aimed rotatable mirrors and laser beam to define one of lines of sight. Adjusts automatically to bring two lines of sight into convergence at common point on object.

  14. Television-and-Laser Range-Measuring System

    NASA Technical Reports Server (NTRS)

    Russell, J. Kevin

    1988-01-01

    Triangulation system measures angle between two lines of sight to point on object, determining distance to object. Amenable to automation. Includes automatically aimed rotatable mirrors and laser beam to define one of lines of sight. Adjusts automatically to bring two lines of sight into convergence at common point on object.

  15. Effects of Mountain Ranges on Mesoscale Systems Development.

    DTIC Science & Technology

    1985-09-01

    and July should be suiiall; insolation is more intense in June, but ambient air (and soil) temperatures are warmer in July. In Figs. 1-24, convection...merging of these lines, making the case appear similar in many respects to the " derecho " as described by Johns and Hirt (1983). We note qualitatively... derecho ...A severe weather producing convective system. Preprints. 13th Conf. Severe Local Storms, Amer. Meteor. Soo., 17-20 October, Tulsa, Oklahoma

  16. Long Range Plan for Embedded Computer Systems Support. Volume II

    DTIC Science & Technology

    1981-10-01

    Architecture ................................. 3-39 3-9. Support of M ulti-Use ECS .......................................... 3-40 3-10. Use of Emulation...Software Test Bed Architectures ............................. 4-30 4-4. Example Integration Test Bed Architectures ....................... 4-31 4-5...testability along with increased interface control and stan- dardization of languages and instruction set architectures . Support systems will be modular

  17. Alternatives for Long-Range Ground-Attack Systems

    DTIC Science & Technology

    2006-03-01

    operations. The study compares the advantages, disadvantages, and costs of eight alternative systems—five aircraft -based systems and three missile-based...Characteristics of Supersonic Missiles for the Arsenal Aircraft (Alternative 1) 38A-2. Acquisition Costs of Supersonic Missiles for the Arsenal Aircraft ...Alternative 39A-3. Summary of CBO’s Cost Estimating Methods for Supersonic Missiles in Alternative 1 40A-4. Characteristics of Bomber Aircraft 43A-5

  18. Range gated active night vision system for automobiles.

    PubMed

    David, Ofer; Kopeika, Norman S; Weizer, Boaz

    2006-10-01

    Night vision for automobiles is an emerging safety feature that is being introduced for automotive safety. We develop what we believe is an innovative new night vision system using gated imaging principles. The concept of gated imaging is described and its basic advantages, including the backscatter reduction mechanism for improved vision through fog, rain, and snow. Evaluation of performance is presented by analyzing bar pattern modulation and comparing Johnson chart predictions.

  19. Spectroscopic imaging system for high-throughput viability assessment of ovarian spheroids or microdissected tumor tissues (MDTs) in a microfluidic chip

    NASA Astrophysics Data System (ADS)

    St-Georges-Robillard, A.; Masse, M.; Kendall-Dupont, J.; Strupler, M.; Patra, B.; Jermyn, M.; Mes-Masson, A.-M.; Leblond, F.; Gervais, T.

    2016-02-01

    There is a growing effort in the biomicrosystems community to develop a personalized treatment response assay for cancer patients using primary cells, patient-derived spheroids, or live tissues on-chip. Recently, our group has developed a technique to cut tumors in 350 μm diameter microtissues and keep them alive on-chip, enabling multiplexed in vitro drug assays on primary tumor tissue. Two-photon microscopy, confocal microscopy and flow cytometry are the current standard to assay tissue chemosensitivity on-chip. While these techniques provide microscopic and molecular information, they are not adapted for high-throughput analysis of microtissues. We present a spectroscopic imaging system that allows rapid quantitative measurements of multiple fluorescent viability markers simultaneously by using a liquid crystal tunable filter to record fluorescence and transmittance spectra. As a proof of concept, 24 spheroids composed of ovarian cancer cell line OV90 were formed in a microfluidic chip, stained with two live cell markers (CellTrackerTM Green and Orange), and imaged. Fluorescence images acquired were normalized to the acquisition time and gain of the camera, dark noise was removed, spectral calibration was applied, and spatial uniformity was corrected. Spectral un-mixing was applied to separate each fluorophore's contribution. We have demonstrated that rapid and simultaneous viability measurements on multiple spheroids can be achieved, which will have a significant impact on the prediction of a tumor's response to multiple treatment options. This technique may be applied as well in drug discovery to assess the potential of a drug candidate directly on human primary tissue.

  20. Micron-Accurate Laser Fresnel-Diffraction Ranging System

    NASA Technical Reports Server (NTRS)

    Lehner, David; Campbell, Jonathan; Smith, Kelly; Sanders, Alvin; Allison, Stephen; Smaley, Larry

    2008-01-01

    Two versions of an optoelectronic system undergoing development are depicted. The system is expected to be capable of measuring a distance between 2 and 10 m with an error of no more than 1 micrometer. The system would be designed to exploit Fresnel diffraction of a laser beam. In particular, it would be designed to take advantage of the fact that a Fresnel diffraction pattern is ultrasensitive to distance. The two versions would differ in the following respects: In version 1, the focus of the telescope would be in the Fresnel region, and the telescope would have a small depth of focus. As a consequence, the Fresnel pattern would be imaged directly onto the photodetector array; in version 2, a multielement lens module would displace the Fresnel region from the vicinity of the pinhole to the vicinity of the optical receiver. As the distance to be measured varied, the location of the receiver relative to the displaced Fresnel-diffraction region would vary, thereby causing the Fresnel diffraction pattern on the focal plane to vary. The multielement lens module would also correct for aberrations. The processing of the digitized Fresnel diffraction pattern in the computer might be accelerated by using only parts of the pattern or even only one small part - the central pixel. As the distance from the pinhole increased, the central pixel would rapidly cycle between maximum and minimum light intensity. This in itself would not be sufficient to uniquely determine the distance. However, by varying the size of the pinhole or the wavelength of the laser, one could obtain a second cycle of variation of intensity that, in conjunction with the first cycle, could enable a unique determination of distance. Alternatively, for a single wavelength and a single pinhole size, it should suffice to consider the data from only two different key pixels in the Fresnel pattern.

  1. System dynamic modelling to assess economic viability and risk trade-offs for ecological restoration in South Africa.

    PubMed

    Crookes, D J; Blignaut, J N; de Wit, M P; Esler, K J; Le Maitre, D C; Milton, S J; Mitchell, S A; Cloete, J; de Abreu, P; Fourie nee Vlok, H; Gull, K; Marx, D; Mugido, W; Ndhlovu, T; Nowell, M; Pauw, M; Rebelo, A

    2013-05-15

    Can markets assist by providing support for ecological restoration, and if so, under what conditions? The first step in addressing this question is to develop a consistent methodology for economic evaluation of ecological restoration projects. A risk analysis process was followed in which a system dynamics model was constructed for eight diverse case study sites where ecological restoration is currently being pursued. Restoration costs vary across each of these sites, as do the benefits associated with restored ecosystem functioning. The system dynamics model simulates the ecological, hydrological and economic benefits of ecological restoration and informs a portfolio mapping exercise where payoffs are matched against the likelihood of success of a project, as well as a number of other factors (such as project costs and risk measures). This is the first known application that couples ecological restoration with system dynamics and portfolio mapping. The results suggest an approach that is able to move beyond traditional indicators of project success, since the effect of discounting is virtually eliminated. We conclude that systems dynamic modelling with portfolio mapping can guide decisions on when markets for restoration activities may be feasible.

  2. Cartilage viability after trochleoplasty.

    PubMed

    Schöttle, Philip B; Schell, Hanna; Duda, Georg; Weiler, Andreas

    2007-02-01

    Trochleoplasty is an established and accepted technique for the treatment of patellar instability because of a missing trochlear groove. In this technique, a flap of cartilage over the trochlea is carefully removed and a new trochlear groove is created in the underlying bone before the cartilaginous flap is reattached with sutures. The mid-term clinical and radiological results of this operation are promising but no information about the viability of the reattached cartilage has been reported. To evaluate cartilage viability and quality after trochleoplasty and to verify the healing process, two osteochondral biopsies were harvested from three patients 6, 8, and 9 months after trochleoplasty. One cylinder was evaluated histologically to assess cartilage, calcified cartilage (cc), and subchondral bone quality, while the other one was examined by confocal microscopy to evaluate cell viability. The histological examination showed a normal matrix and cell distribution of the cartilage, while the cc showed lacunae ingrowing from the underlying bone. The subchondral bone showed normal lamellae and histology, and the healing of the flap. Confocal microscopy showed almost exclusively viable chondrocytes. This demonstration of non-injured cartilage at short-term follow-up together with promising clinical and radiological 2- and 5-year follow-up results indicate a potential promising outlook for the long term, as further chondral damage is not expected. So trochleoplasty can be seen as a primary intervention for patellar instability because of trochlear dysplasia as the risk for cartilage damage is low.

  3. Development of the Acoustic Ranging System Toward the Cable Network System

    NASA Astrophysics Data System (ADS)

    Osada, Y.; Kido, M.; Fujimoto, H.; Tadokoro, K.; Kaneda, Y.

    2008-12-01

    We have developed a short-range seafloor ranging system as a possible future application to the DONET (Dense Oceanfloor Network System for Earthquakes and Tsunamis) cable system. Direct acoustic ranging is a simple way to monitor local crustal deformation, and various groups have successfully detected deformation on the seafloor using such a system. We aim to monitor the splay faults in the rupture area of the Tonankai earthquake in Nankai subduction zone (Park et al, 2002). Slip along the active splay faults may be an important mechanism that accommodates the elastic strain caused by relative plate motion. We plan to deploy PXPs (precise acoustic transponder) across the splay faults in the Kumano-nada area to measure the horizontal crustal movement to the accuracy required to detect VLF (Very Low Frequency) earthquakes. On the first step we collected 660 ranging data in this one-day experiment. The round trip travel time shows a variation with peak-to-peak amplitude of about 25 mm in the range. It was confirmed that most of the variation could be explained by the change in sound speed estimated from measured temperature and pressure. The remaining fluctuation in the acoustic measurements is +/-2 mm. On the next step, we carried out the experiment to estimate the accuracy of the long period. It collected the data during four month because it had made a trouble. Therefore we can recovery only two slave PXPs. We try to recovery two master PXPs using Hyper dolphin on September 2008. We report on the experiment with a direct acoustic ranging system and estimate the accuracy of the acoustic measurements for the middle period.

  4. Zoom athermal telescope having 18.5 magnification range for 8 to 12-u range FLIR systems

    NASA Astrophysics Data System (ADS)

    Shechterman, Mark S.

    1995-10-01

    This paper describes the specific design considerations and performance evaluation for ELOP's MLZFS (modular lightweight zoom FLIR system) utilizing a new athermal wide magnification range IR zoom telescope. The following aspects of the development work are discussed in this paper: MTF and MRT characteristics of the FLIR for different temperatures; comparison with existing zoom systems and with systems of discrete magnification change; calculation of lens group positions as a function of magnification and temperature, including interpolation analyses of these dependencies; implemented methods for narcissus effect reduction at the lowest magnification mode, including development of a new AR coating; critical tolerance analyses; mechanical and electro-mechanical design, answering high accuracy requirements; adjustment and calibration of the zoom system by use of an IR interferometer.

  5. Low pressure EGR system having full range capability

    DOEpatents

    Easley, Jr. William Lanier; Milam, David Michael; Roozenboom, Stephan Donald; Bond, Michael Steven; Kapic, Amir

    2009-09-22

    An exhaust treatment system for an engine is disclosed and may have an air induction circuit, an exhaust circuit, and an exhaust recirculation circuit. The air induction circuit may be configured to direct air into the engine. The exhaust circuit may be configured to direct exhaust from the engine and include a turbine driven by the exhaust, a particulate filter disposed in series with and downstream of the turbine, and a catalytic device disposed in series with and downstream of the particulate filter. The exhaust recirculation circuit may be configured to selectively redirect at least some of the exhaust from between the particulate filter and the catalytic device to the air induction circuit. The catalytic device is selected to create backpressure within the exhaust circuit sufficient to ensure that, under normal engine operating conditions above low idle, exhaust can flow into the air induction circuit without throttling of the air.

  6. Twin-arginine translocation system in Helicobacter pylori: TatC, but not TatB, is essential for viability.

    PubMed

    Benoit, Stéphane L; Maier, Robert J

    2014-01-21

    The twin-arginine translocation (Tat) system, needed to transport folded proteins across biological membranes, has not been characterized in the gastric pathogen Helicobacter pylori. Analysis of all H. pylori genome sequences available thus far reveals the presence of single copies of tatA, tatB, and tatC needed for the synthesis of a fully functional Tat system. Based on the presence of the twin-arginine hallmark in their signal sequence, only four H. pylori proteins appear to be Tat dependent: hydrogenase (HydA), catalase-associated protein (KapA), biotin sulfoxide reductase (BisC), and the ubiquinol cytochrome oxidoreductase Rieske protein (FbcF). In the present study, targeted mutations were aimed at tatA, tatB, tatC, or queA (downstream gene control). While double homologous recombination mutations in tatB and queA were easily obtained, attempts at disrupting tatA proved unsuccessful, while deletion of tatC led to partial mutants following single homologous recombination, with cells retaining a chromosomal copy of tatC. Double homologous recombination tatC mutants were obtained only when a plasmid-borne, isopropyl-β-d-thiogalactopyranoside (IPTG)-inducible copy of tatC was introduced prior to transformation. These conditional tatC mutants could grow only in the presence of IPTG, suggesting that tatC is essential in H. pylori. tatB and tatC mutants had lower hydrogenase and catalase activities than the wild-type strain did, and the ability of tatC mutants to colonize mouse stomachs was severely affected compared to the wild type. Chromosomal complementation of tatC mutants restored hydrogenase and catalase activities to wild-type levels, and additional expression of tatC in wild-type cells resulted in elevated Tat-dependent enzyme activities. Unexpectedly, the tat strains had cell envelope defects. This work reports the first characterization of the twin-arginine translocation (Tat) system in the gastric pathogen Helicobacter pylori. While tatB mutants were

  7. Viability of Acanthamoeba after exposure to a multipurpose disinfecting contact lens solution and two hydrogen peroxide systems

    PubMed Central

    Hiti, K; Walochnik, J; Haller-Schober, E M; Faschinger, C; Aspöck, H

    2002-01-01

    Background/aim: Contact lens cases contaminated with Acanthamoeba are a major risk factor for an infection of the eye. In this study the anti-Acanthamoeba activity of three different contact lens storage solutions was tested. Methods: A new multipurpose contact lens storage solution (Meni Care Plus) and a two step (Titmus H2O2) and one step (Oxysept Comfort) hydrogen peroxide system were tested for their effects on trophozoites and cysts of three different Acanthamoeba species: A castellanii, A hatchetti, and A lenticulata. Results: After a soaking time of 8 hours (overnight soaking of contact lenses) the Titmus H2O2 0.6% solution showed very good amoebicidal effects, while Oxysept Comfort 3% H2O2 could not effectively destroy the cysts of any of the three tested species. Viable cysts of the species A lenticulata and A hatchetti were still present after exposure to Meni Care Plus (0.0005% PHMB) for 8 hours. Conclusion: Not all of the three tested contact lens storage solutions have sufficient amoebicidal effects. The two step peroxide system Titmus H2O2 is a very effective disinfectant contact lens solution in order to avoid a possible Acanthamoeba infection of the eye. PMID:11815336

  8. Monocular Passive Ranging by an Optical System with Band Pass Filtering

    DTIC Science & Technology

    2010-03-01

    MONOCULAR PASSIVE RANGING BY AN OPTICAL SYSTEM WITH BAND PASS FILTERING THESIS Joel R...GAP/ENP/10-M01 MONOCULAR PASSIVE RANGING BY AN OPTICAL SYSTEM WITH BAND PASS FILTERING THESIS Presented to the Faculty Department of...March 2010 APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED AFIT/GAP/ENP/10-M01 MONOCULAR PASSIVE RANGING BY AN OPTICAL SYSTEM WITH BAND

  9. Viability of Bacillus subtilis spores exposed to space environment in the M-191 experiment system aboard Apollo 16.

    PubMed

    Bucker, H; Horneck, G; Wollenhaupt, H; Schwager, M; Taylor, G R

    1974-01-01

    During the Apollo 16 space flight, in the experiment system M-191, (microbial response to space environment) spores of Bacillus subtilis 168 were exposed to space vacuum or solar UV irradiation with a peak wavelength of 254 nm or both. The effects of these space factors on the colony-forming ability of the spores were studied. It was found (i) that space vacuum alone did not affect the survival of pre-dried spores; (ii) that space vacuum in combination with solar UV irradiation with a peak wavelength of 254 nm had a synergistic effect, which may by attributed to a UV supersensitivity of the spores during vacuum exposure. These results agreed with findings of simulation experiments on earth. It was concluded that air dried spores may survive exposure to space vacuum if shielded against solar UV irradiation.

  10. Managing the U.S. Economy in a Post-Attack Environment. A System Dynamics Model of Viability.

    DTIC Science & Technology

    1979-11-01

    Dynamics. New York: John Wiley and Sons, 1977. "On the Scope and Purpose of Industrial Dynamics." International Journal of Systems Sciences, Vol. 4, No...IRED LEVEL OF FOOD1 fRI01IVI (N Nl TF L-NET F foor SIJPPL-Y ( F:l,CK0lLkS COMFAPLE I󈧎i F 001P)IPF - FOOD’ IN [RC’rL l] (’N A i T Hr F oT’E!;i..Y Sir ...Disaster Research Center 7655 Old Spring Road 127-129 West 10th Avenue McLean, Virginia 22101 Columbus, Ohio 43201 Mr. John Billheimer Defense

  11. FORAGES AND PASTURES SYMPOSIUM: Improving efficiency of production in pasture- and range-based beef and dairy systems.

    PubMed

    Mulliniks, J T; Rius, A G; Edwards, M A; Edwards, S R; Hobbs, J D; Nave, R L G

    2015-06-01

    Despite overall increased production in the last century, it is critical that grazing production systems focus on improving beef and dairy efficiency to meet current and future global food demands. For livestock producers, production efficiency is essential to maintain long-term profitability and sustainability. This continued viability of production systems using pasture- and range-based grazing systems requires more rapid adoption of innovative management practices and selection tools that increase profitability by optimizing grazing management and increasing reproductive performance. Understanding the genetic variation in cow herds will provide the ability to select cows that require less energy for maintenance, which can potentially reduce total energy utilization or energy required for production, consequently improving production efficiency and profitability. In the United States, pasture- and range-based grazing systems vary tremendously across various unique environments that differ in climate, topography, and forage production. This variation in environmental conditions contributes to the challenges of developing or targeting specific genetic components and grazing systems that lead to increased production efficiency. However, across these various environments and grazing management systems, grazable forage remains the least expensive nutrient source to maintain productivity of the cow herd. Beef and dairy cattle can capitalize on their ability to utilize these feed resources that are not usable for other production industries. Therefore, lower-cost alternatives to feeding harvested and stored feedstuffs have the opportunity to provide to livestock producers a sustainable and efficient forage production system. However, increasing production efficiency within a given production environment would vary according to genetic potential (i.e., growth and milk potential), how that genetic potential fits the respective production environment, and how the grazing

  12. Observability in strategic models of viability selection.

    PubMed

    Gámez, M; Carreño, R; Kósa, A; Varga, Z

    2003-10-01

    Strategic models of frequency-dependent viability selection, in terms of mathematical systems theory, are considered as a dynamic observation system. Using a general sufficient condition for observability of nonlinear systems with invariant manifold, it is studied whether, observing certain phenotypic characteristics of the population, the development of its genetic state can be recovered, at least near equilibrium.

  13. Twin-Arginine Translocation System in Helicobacter pylori: TatC, but Not TatB, Is Essential for Viability

    PubMed Central

    Benoit, Stéphane L.; Maier, Robert J.

    2014-01-01

    ABSTRACT The twin-arginine translocation (Tat) system, needed to transport folded proteins across biological membranes, has not been characterized in the gastric pathogen Helicobacter pylori. Analysis of all H. pylori genome sequences available thus far reveals the presence of single copies of tatA, tatB, and tatC needed for the synthesis of a fully functional Tat system. Based on the presence of the twin-arginine hallmark in their signal sequence, only four H. pylori proteins appear to be Tat dependent: hydrogenase (HydA), catalase-associated protein (KapA), biotin sulfoxide reductase (BisC), and the ubiquinol cytochrome oxidoreductase Rieske protein (FbcF). In the present study, targeted mutations were aimed at tatA, tatB, tatC, or queA (downstream gene control). While double homologous recombination mutations in tatB and queA were easily obtained, attempts at disrupting tatA proved unsuccessful, while deletion of tatC led to partial mutants following single homologous recombination, with cells retaining a chromosomal copy of tatC. Double homologous recombination tatC mutants were obtained only when a plasmid-borne, isopropyl-β-d-thiogalactopyranoside (IPTG)-inducible copy of tatC was introduced prior to transformation. These conditional tatC mutants could grow only in the presence of IPTG, suggesting that tatC is essential in H. pylori. tatB and tatC mutants had lower hydrogenase and catalase activities than the wild-type strain did, and the ability of tatC mutants to colonize mouse stomachs was severely affected compared to the wild type. Chromosomal complementation of tatC mutants restored hydrogenase and catalase activities to wild-type levels, and additional expression of tatC in wild-type cells resulted in elevated Tat-dependent enzyme activities. Unexpectedly, the tat strains had cell envelope defects. PMID:24449753

  14. Web-GIS oriented systems viability for municipal solid waste selective collection optimization in developed and transient economies

    SciTech Connect

    Rada, E.C.; Ragazzi, M.; Fedrizzi, P.

    2013-04-15

    Highlights: ► As an appropriate solution for MSW management in developed and transient countries. ► As an option to increase the efficiency of MSW selective collection. ► As an opportunity to integrate MSW management needs and services inventories. ► As a tool to develop Urban Mining actions. - Abstract: Municipal solid waste management is a multidisciplinary activity that includes generation, source separation, storage, collection, transfer and transport, processing and recovery, and, last but not least, disposal. The optimization of waste collection, through source separation, is compulsory where a landfill based management must be overcome. In this paper, a few aspects related to the implementation of a Web-GIS based system are analyzed. This approach is critically analyzed referring to the experience of two Italian case studies and two additional extra-European case studies. The first case is one of the best examples of selective collection optimization in Italy. The obtained efficiency is very high: 80% of waste is source separated for recycling purposes. In the second reference case, the local administration is going to be faced with the optimization of waste collection through Web-GIS oriented technologies for the first time. The starting scenario is far from an optimized management of municipal solid waste. The last two case studies concern pilot experiences in China and Malaysia. Each step of the Web-GIS oriented strategy is comparatively discussed referring to typical scenarios of developed and transient economies. The main result is that transient economies are ready to move toward Web oriented tools for MSW management, but this opportunity is not yet well exploited in the sector.

  15. Production traits of artificially and naturally hatched geese in intensive and free-range systems: I. Growth traits.

    PubMed

    Boz, M A; Sarica, M; Yamak, U S

    2017-04-01

    1. This study investigated the effect of incubation type and production system on geese growth traits. 2. A total of 216 geese were either naturally (114) or artificially (102) hatched and reared in intensive or free-range production systems (4 replicates each) until 18 weeks of age. 3. Weights of naturally hatched goslings (NHG) were significantly higher than artificially hatched goslings (AHG) at 2 weeks (644 vs. 536 g); however, weights of AHG were significantly higher than NHG at both 6 weeks (3245 vs. 3010 g) and 18 weeks (5212 vs. 4353 g). 4. AHG had better feed conversion ratios (FCRs) than NHG (6.21 vs. 6.46 at 18 weeks). Feed consumption of naturally hatched geese was found higher in first 4 weeks when compared to artificially hatched geese and artificially hatched geese consumed more feed than naturally hatched geese after 8 weeks. 5. Production system had insignificant effects on feed consumption, FCRs, viability and mutilation rates. 6. Slipped wings were more frequent in NHG than AHG (8.32% vs. 1.68% at 6 weeks; 23.84% vs. 5.12% between 7 and 18 weeks) and in free-range production when compared to intensive production (17.88% vs. 11.08% over the course of the production period). 7. The study results indicate that both artificially and NHG can be reared in free-range production systems without any loss in performance and in deference to animal welfare.

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

    NASA Technical Reports Server (NTRS)

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

    1997-01-01

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

  17. The role of heterogeneity in long-range interacting systems: From nucleation to earthquake fault systems

    NASA Astrophysics Data System (ADS)

    Silva, James Brian

    The role of heterogeneity in two long-range systems is explored with a focus on the interplay of this heterogeneity with the component system interactions. The first will be the heterogeneous Ising model with long-range interactions. Earthquake fault systems under long-range stress transfer with varying types of heterogeneity will be the second system of interest. First I will review the use of the intervention method to determine the time and place of nucleation and extend its use as an indicator for spinodal nucleation. The heterogeneous Ising model with fixed magnetic sites will then be reformulated as a dilute random field Ising model. This reformulation will allow for the application of spinodal nucleation theory to the heterogeneous Ising model by correcting the spinodal field and the critical exponent sigma describing the critical behavior of clusters in spinodal nucleation theory. The applicability of this correction is shown by simulations that determine the cluster scaling of the nucleating droplets near the spinodal. Having obtained a reasonable definition of the saddle point object describing the nucleation droplet, the density profile of the nucleating droplet is measured and deviations from homogeneous spinodal nucleation are found due to the excess amount of sparseness in the nucleating droplet due to the heterogeneity. Earthquake fault systems are then introduced and a connection is shown of two earthquake models. Heterogeneity is introduced in the form of asperities with the intent of modeling the effect of hard rocks on earthquake statistics. The asperities are observed to be a crucial element in explaining the behavior of aftershocks resulting in Omori's law. A second form of heterogeneity is introduced by coupling the Olami-Feder-Christensen model to an invasion percolation model for the purpose of modeling an earthquake fault system undergoing hydraulic fracturing. The ergodicty and event size statistics are explored in this extended model. The

  18. Establishing lunar resource viability

    NASA Astrophysics Data System (ADS)

    Carpenter, J.; Fisackerly, R.; Houdou, B.

    2016-11-01

    Recent research has highlighted the potential of lunar resources as an important element of space exploration but their viability has not been demonstrated. Establishing whether or not they can be considered in future plans is a multidisciplinary effort, requiring scientific expertise and delivering scientific results. To this end various space agencies and private entities are looking to lunar resources, extracted and processed in situ, as a potentially game changing element in future space architectures, with the potential to increase scale and reduce cost. However, before any decisions can be made on the inclusion of resources in exploration roadmaps or future scenarios some big questions need to be answered about the viability of different resource deposits and the processes for extraction and utilisation. The missions and measurements that will be required to answer these questions, and which are being prepared by agencies and others, can only be performed through the engagement and support of the science community. In answering questions about resources, data and knowledge will be generated that is of fundamental scientific importance. In supporting resource prospecting missions the science community will de facto generate new scientific knowledge. Science enables exploration and exploration enables science.

  19. 26 CFR 12.4 - Election of Class Life Asset Depreciation Range System (ADR).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 14 2011-04-01 2010-04-01 true Election of Class Life Asset Depreciation Range... Election of Class Life Asset Depreciation Range System (ADR). (a) Elections filed before February 1, 1972... the Asset Depreciation Range System published in the Federal Register for June 23, 1971),...

  20. 26 CFR 12.4 - Election of Class Life Asset Depreciation Range System (ADR).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 14 2012-04-01 2012-04-01 false Election of Class Life Asset Depreciation Range... Election of Class Life Asset Depreciation Range System (ADR). (a) Elections filed before February 1, 1972... the Asset Depreciation Range System published in the Federal Register for June 23, 1971),...

  1. Synthesis and analysis of precise spaceborne laser ranging systems, volume 2. [Spacelab payload

    NASA Technical Reports Server (NTRS)

    Paddon, E. A.

    1978-01-01

    The performance capabilities of specific shuttle-based laser ranging systems were evaluated, and interface and support requirements were determined. The preliminary design of a shuttle-borne laser ranging experiment developed as part of the Spacelab program is discussed.

  2. Artificial Evolution by Viability Rather than Competition

    PubMed Central

    Maesani, Andrea; Fernando, Pradeep Ruben; Floreano, Dario

    2014-01-01

    Evolutionary algorithms are widespread heuristic methods inspired by natural evolution to solve difficult problems for which analytical approaches are not suitable. In many domains experimenters are not only interested in discovering optimal solutions, but also in finding the largest number of different solutions satisfying minimal requirements. However, the formulation of an effective performance measure describing these requirements, also known as fitness function, represents a major challenge. The difficulty of combining and weighting multiple problem objectives and constraints of possibly varying nature and scale into a single fitness function often leads to unsatisfactory solutions. Furthermore, selective reproduction of the fittest solutions, which is inspired by competition-based selection in nature, leads to loss of diversity within the evolving population and premature convergence of the algorithm, hindering the discovery of many different solutions. Here we present an alternative abstraction of artificial evolution, which does not require the formulation of a composite fitness function. Inspired from viability theory in dynamical systems, natural evolution and ethology, the proposed method puts emphasis on the elimination of individuals that do not meet a set of changing criteria, which are defined on the problem objectives and constraints. Experimental results show that the proposed method maintains higher diversity in the evolving population and generates more unique solutions when compared to classical competition-based evolutionary algorithms. Our findings suggest that incorporating viability principles into evolutionary algorithms can significantly improve the applicability and effectiveness of evolutionary methods to numerous complex problems of science and engineering, ranging from protein structure prediction to aircraft wing design. PMID:24489790

  3. Physico-chemical characterization of asolectin-genistein liposomal system: An approach to analyze its in vitro antioxidant potential and effect in glioma cells viability.

    PubMed

    Lopes de Azambuja, Carla Roberta; dos Santos, Lurdiane Gomes; Rodrigues, Marisa Raquel; Rodrigues, Renan Ferreira Meneses; da Silveira, Elita Ferreira; Azambuja, Juliana Hofstatter; Flores, Alex F C; Horn, Ana Paula; Dora, Cristiana Lima; Muccillo-Baisch, Ana Luisa; Braganhol, Elizandra; da Silva Pinto, Luciano; Parize, Alexandre Luís; de Lima, Vânia Rodrigues

    2015-12-01

    In this study, the interaction between soy isoflavone genistein and asolectin liposomes was investigated by monitoring the effects of isoflavone on lipidic hydration, mobility, location and order. These properties were analyzed by the following techniques: horizontal attenuated total reflection Fourier transform infrared spectroscopy (HATR-FTIR), low-field (1)H nuclear magnetic resonance (NMR), high-field (31)P NMR, zeta potential, differential scanning calorimetry (DSC) and UV-vis spectroscopy. The antioxidant and antitumoral activities of the genistein liposomal system were also studied. The genistein saturation concentration in ASO liposomes corresponded to 484 μM. HATR-FTIR results indicated that genistein influences the dynamics of the lipidic phosphate, choline, carbonyl and acyl chain methylenes groups. At the lipid polar head, HATR-FTIR and (31)P NMR results showed that the isoflavone reduces the hydration degree of the phosphate group, as well as its mobility. Genistein ordered the lipid interfacial carbonyl group, as evidenced by the HATR-FTIR bandwidth analysis. This ordering effect was also observed in the lipidic hydrophobic region, by HATR-FTIR, NMR, DSC and turbidity responses. At the saturation concentration, liposome-loaded genistein inhibits the lipid peroxidation induced by hydroxyl radical in 90.9%. ASO liposome-loaded genistein at 100 μM decreased C6 glioma cell viability by 57% after 72 h of treatment. Results showed an increase of the genistein in vitro activities after its incorporation in liposomes. The data described in this work will contribute to a better understanding of the interaction between genistein and a natural-source membrane and of its influence on isoflavone biological activities. Furthermore, the antitumoral results showed that genistein-based liposomes, which contain natural-sourced lipids, may be promising as a drug delivery system to be used in the glioma therapy. Copyright © 2015 Elsevier Ireland Ltd. All rights

  4. Innovative free space optical communication and navigation system with high data rate communication, precision ranging, range rate measurements, and accurate spacecraft pointing

    NASA Astrophysics Data System (ADS)

    Yang, Guangning; Lu, Wei; Sun, Xiaoli; Chen, Jeffrey; Krainak, Michael

    2016-03-01

    We report an innovative free Space optical communication and navigation system which provides high data rate communication, precise measurements of spacecraft ranging, range rate, and accurate spacecraft pointing. A complete breadboard system was built. It includes both space and ground terminals. Along with 622MBPS data link, two way ranging were conducted. 23μm ranging and 23μm/s range rate accuracies were achieved in 1 second integrating time. These ranging performance is not sensitive to the communication error rate. The high ranging and range rate accuracies were achieved through the relative phase measurement of transmit and receive clock with Dual Mixer Timer Difference measurement apparatus.

  5. Modeling methodology for MLS range navigation system errors using flight test data

    NASA Technical Reports Server (NTRS)

    Karmali, M. S.; Phatak, A. V.

    1982-01-01

    Flight test data was used to develop a methodology for modeling MLS range navigation system errors. The data used corresponded to the constant velocity and glideslope approach segment of a helicopter landing trajectory. The MLS range measurement was assumed to consist of low frequency and random high frequency components. The random high frequency component was extracted from the MLS range measurements. This was done by appropriate filtering of the range residual generated from a linearization of the range profile for the final approach segment. This range navigation system error was then modeled as an autoregressive moving average (ARMA) process. Maximum likelihood techniques were used to identify the parameters of the ARMA process.

  6. Effect on maximum ranging distance of laser range finder in different visibility with power fluctuation of emitting system

    NASA Astrophysics Data System (ADS)

    Chen, Yu-dan; Zhou, Bing; Xu, Chun-mei; Liu, Jie; Huang, Fu-yu; Zhang, Fang

    2016-01-01

    One of the most important qualifications of laser range finder is the ranging distance. The ranging distance of laser range finder is usually supplied with a atmosphere condition. To reach the qualification of ranging distance, the manufacturers always increase the laser emitting power which the laser range finders can work not only in the ranging distance. It is important to find the real ranging distance in different visibility especially for military application. The maximum ranging distances in different visibility were discussed in the paper. First, the power of different types of laser range finder was got by experiment. The power of two models of laser range finder was got, and the power of same model but two serial numbers was obtained. Then, the fluctuation regularity was discussed. Then, the maximum ranging distances in different visibility were got by numerical simulation. The maximum ranging distances of laser range finder with same model but two serial numbers were calculated. The figures of maximum ranging distances varying with visibility were obtained. It was showed that the maximum ranging distances of laser range finder with same model but two serial numbers were different.

  7. Damage assessment of long-range rocket system by electromagnetic pulse weapon

    NASA Astrophysics Data System (ADS)

    Cao, Lingyu; Liu, Guoqing; Li, Jinming

    2017-08-01

    This paper analyzes the damage mechanism and characteristics of electromagnetic pulse weapon, establishes the index system of survivability of long-range rocket launcher system, and uses AHP method to establish the combat effectiveness model of long-range rocket missile system. According to the damage mechanism and characteristics of electromagnetic pulse weapon, the damage effect of the remote rocket system is established by using the exponential method to realize the damage efficiency of the remote rocket system.

  8. Nonlinear Time-Variant Response in an Avalanche Photodiode Array Based Laser Detection and Ranging System

    DTIC Science & Technology

    2007-03-01

    Nonlinear Time-Variant Response in an Avalanche Photodiode Array Based Laser Detection and Ranging System THESIS Michael D. Seal, Captain, USAF AFIT...DISTRIBUTION UNLIMITED. AFIT/GEO/ENG/07-03 Nonlinear Time-Variant Response in an Avalanche Photodiode Array Based Laser Detection and Ranging System...time-variant behavior exhibited by an avalanche photodiode (APD) array based laser ranging and detec- tion (LADAR) system. This examination was

  9. Multiple rate digital command detection system with range clean-up capability

    NASA Technical Reports Server (NTRS)

    Lesh, J. R.; Butman, S. A. (Inventor)

    1977-01-01

    A multi-rate digital command system is disclosed which uses the composite signal of a mu-type ranging system as a subcarrier to transmit range codes and data from a station to a receiver where the range codes are sequentially phase modulated on a subcarrier of frequency by one of its own subharmonics and data is phase modulated on a selected ranging component. A range cleanup loop in a spacecraft locks the phase of a locally generated reference component to a received ranging component and retransmits the component to a ground station. When the inverse phase of a ranging component is received and detected, the cleanup loop is modified to demodulate phase modulated command symbols while continuing tracking the same ranging component. The command symbol rate is coherently related to the ranging signal component bit rate.

  10. The Evaluation of the Regional Atmospheric Modeling System in the Eastern Range Dispersion Assessment System

    NASA Technical Reports Server (NTRS)

    Case, Jonathan

    2001-01-01

    The Applied Meteorology Unit (AMU) evaluated the Regional Atmospheric Modeling System (RAMS) contained within the Eastern Range Dispersion Assessment System (ERDAS). ERDAS provides emergency response guidance for Cape Canaveral Air Force Station and Kennedy Space Center operations in the event of an accidental hazardous material release or aborted vehicle launch. The RAMS prognostic data are available to ERDAS for display and are used to initialize the 45th Space Wing/Range Safety dispersion model. Thus, the accuracy of the dispersion predictions is dependent upon the accuracy of RAMS forecasts. The RAMS evaluation consisted of an objective and subjective component for the 1999 and 2000 Florida warm seasons, and the 1999-2000 cool season. In the objective evaluation, the AMU generated model error statistics at surface and upper-level observational sites, compared RAMS errors to a coarser RAMS grid configuration, and benchmarked RAMS against the nationally-used Eta model. In the subjective evaluation, the AMU compared forecast cold fronts, low-level temperature inversions, and precipitation to observations during the 1999-2000 cool season, verified the development of the RAMS forecast east coast sea breeze during both warm seasons, and examined the RAMS daily thunderstorm initiation and precipitation patterns during the 2000 warm season. This report summarizes the objective and subjective verification for all three seasons.

  11. Evaluation of the Regional Atmospheric Modeling System in the Eastern Range Dispersion Assessment System

    NASA Technical Reports Server (NTRS)

    Case, Jonathan

    2000-01-01

    The Applied Meteorology Unit is conducting an evaluation of the Regional Atmospheric Modeling System (RAMS) contained within the Eastern Range Dispersion Assessment System (ERDAS). ERDAS provides emergency response guidance for operations at the Cape Canaveral Air Force Station and the Kennedy Space Center in the event of an accidental hazardous material release or aborted vehicle launch. The prognostic data from RAMS is available to ERDAS for display and is used to initialize the 45th Range Safety (45 SW/SE) dispersion model. Thus, the accuracy of the 45 SW/SE dispersion model is dependent upon the accuracy of RAMS forecasts. The RAMS evaluation task consists of an objective and subjective component for the Florida warm and cool seasons of 1999-2000. The objective evaluation includes gridded and point error statistics at surface and upper-level observational sites, a comparison of the model errors to a coarser grid configuration of RAMS, and a benchmark of RAMS against the widely accepted Eta model. The warm-season subjective evaluation involves a verification of the onset and movement of the Florida east coast sea breeze and RAMS forecast precipitation. This interim report provides a summary of the RAMS objective and subjective evaluation for the 1999 Florida warm season only.

  12. Motion drive system is accurately controlled in the 1-micron range

    NASA Technical Reports Server (NTRS)

    Morecroft, J. H.

    1966-01-01

    Motion drive system has been developed for use with interferometers where accurate control of minuscule distance in the 1-micron range is of prime importance. The drive system is applicable to any device that requires extremely accurate positioning control.

  13. Research on risk long range identification for vessel traffic dynamic system

    NASA Astrophysics Data System (ADS)

    Qi, Ji; Guo, Ruijuan; Wang, Xiaoyu; Zhang, Hainan

    2017-09-01

    Vessel Long-range identification and tracking system has already been widely installed and applied in vessel. In this paper AIS system, vessel reporting system and LRIT in China are compared and analyzed based on the coverage area, confidentiality and accuracy of the LRIT information. Vessel Long-range identification and tracking model is established through a combination of AIS with LRIT system, which is applied to the research of vessel traffic dynamic system risk long range identification. Finally, the application of LRIT in the maritime field is discussed.

  14. Precision laser range finder system design for Advanced Technology Laboratory applications

    NASA Technical Reports Server (NTRS)

    Golden, K. E.; Kohn, R. L.; Seib, D. H.

    1974-01-01

    Preliminary system design of a pulsed precision ruby laser rangefinder system is presented which has a potential range resolution of 0.4 cm when atmospheric effects are negligible. The system being proposed for flight testing on the advanced technology laboratory (ATL) consists of a modelocked ruby laser transmitter, course and vernier rangefinder receivers, optical beacon retroreflector tracking system, and a network of ATL tracking retroreflectors. Performance calculations indicate that spacecraft to ground ranging accuracies of 1 to 2 cm are possible.

  15. Viability and Resilience of Languages in Competition

    PubMed Central

    Chapel, Laetitia; Castelló, Xavier; Bernard, Claire; Deffuant, Guillaume; Eguíluz, Víctor M.; Martin, Sophie; Miguel, Maxi San

    2010-01-01

    We study the viability and resilience of languages, using a simple dynamical model of two languages in competition. Assuming that public action can modify the prestige of a language in order to avoid language extinction, we analyze two cases: (i) the prestige can only take two values, (ii) it can take any value but its change at each time step is bounded. In both cases, we determine the viability kernel, that is, the set of states for which there exists an action policy maintaining the coexistence of the two languages, and we define such policies. We also study the resilience of the languages and identify configurations from where the system can return to the viability kernel (finite resilience), or where one of the languages is lead to disappear (zero resilience). Within our current framework, the maintenance of a bilingual society is shown to be possible by introducing the prestige of a language as a control variable. PMID:20126655

  16. Performance analysis of single-frequency MPPSK integrated system for ranging applications.

    PubMed

    Yao, Yu; Wu, Lenan

    2014-01-01

    The dual-frequency MPPSK-MODEM is a flexible platform. When ranging accuracy request is low or platform is particularly limited by power, the platform would perform both data transmission and range measurement with single-frequency modes. In this paper, the ranging resolution of MPPSK pulse waveforms with the match filter and impacting filter processing are discussed, respectively. Also, the parameter selection of MPPSK modulator for ranging is considered. In particular, requirements that allow for employing such special parameter values for range measurements with high accuracy and high range are investigated. Moreover, high repetition frequency (HRF) biphase code MPPSK pulse train base on m sequence is presented, and the ranging accuracy of the proposed signal with the match filter processing is deduced. In addition to theoretical considerations, the paper presents system simulations and measurement results of single-frequency MPPSK integrated systems, demonstrating the high-performance of ranging applications.

  17. Performance Analysis of Single-Frequency MPPSK Integrated System for Ranging Applications

    PubMed Central

    Wu, Lenan

    2014-01-01

    The dual-frequency MPPSK-MODEM is a flexible platform. When ranging accuracy request is low or platform is particularly limited by power, the platform would perform both data transmission and range measurement with single-frequency modes. In this paper, the ranging resolution of MPPSK pulse waveforms with the match filter and impacting filter processing are discussed, respectively. Also, the parameter selection of MPPSK modulator for ranging is considered. In particular, requirements that allow for employing such special parameter values for range measurements with high accuracy and high range are investigated. Moreover, high repetition frequency (HRF) biphase code MPPSK pulse train base on m sequence is presented, and the ranging accuracy of the proposed signal with the match filter processing is deduced. In addition to theoretical considerations, the paper presents system simulations and measurement results of single-frequency MPPSK integrated systems, demonstrating the high-performance of ranging applications. PMID:25140340

  18. Long Range Plan for Information Systems from the State Board of Education.

    ERIC Educational Resources Information Center

    Texas Education Agency, Austin.

    The Information Systems Long Range Plan specifically addresses Goal four of the Texas State Board of Education's (SBOE's) "Long-Range Plan for Public School Education" dealing with efficient management and organization of the educational system. To facilitate this goal, the SBOE in 1986 approved and directed the Texas Education Agency to…

  19. Viability of Baylisascaris procyonis Eggs

    PubMed Central

    Sorvillo, Frank J.; Sorvillo, Teresa; Eberhard, Mark L.

    2011-01-01

    Infection with Baylisascaris procyonis roundworms is rare but often fatal and typically affects children. We attempted to determine parameters of viability and methods of inactivating the eggs of these roundworms. Loss of viability resulted when eggs were heated to 62°C or desiccated for 7 months but not when frozen at –15°C for 6 months. PMID:21762591

  20. Viability of Baylisascaris procyonis Eggs.

    PubMed

    Shafir, Shira C; Sorvillo, Frank J; Sorvillo, Teresa; Eberhard, Mark L

    2011-07-01

    Infection with Baylisascaris procyonis roundworms is rare but often fatal and typically affects children. We attempted to determine parameters of viability and methods of inactivating the eggs of these roundworms. Loss of viability resulted when eggs were heated to 62°C or desiccated for 7 months but not when frozen at -15°C for 6 months.

  1. Isotope Brayton electric power system for the 500 to 2500 watt range

    NASA Technical Reports Server (NTRS)

    Macosko, R. P.; Barna, G. J.; Block, H. B.; Ingle, B. D.

    1972-01-01

    An extensive study was conducted at the Lewis Research Center to evaluate an isotope Brayton electric power system for use in the 500 to 2500 W power range. Overall system simplicity was emphasized in order to reduce parasitic power losses and improve system reliability. Detailed parametric cycle analysis, conceptual component designs, and evaluation of system packaging were included. A single-loop system (gas) with six major components including one rotating unit was selected. Calculated net system efficiency varies from 23 to 28 percent over the power range.

  2. Fault Detection and Isolation using Viability Theory and Interval Observers

    NASA Astrophysics Data System (ADS)

    Ghaniee Zarch, Majid; Puig, Vicenç; Poshtan, Javad

    2017-01-01

    This paper proposes the use of interval observers and viability theory in fault detection and isolation (FDI). Viability theory develops mathematical and algorithmic methods for investigating the adaptation to viability constraints of evolutions governed by complex systems under uncertainty. These methods can be used for checking the consistency between observed and predicted behavior by using simple sets that approximate the exact set of possible behavior (in the parameter or state space). In this paper, fault detection is based on checking for an inconsistency between the measured and predicted behaviors using viability theory concepts and sets. Finally, an example is provided in order to show the usefulness of the proposed approach.

  3. Parameter optimization of a dual-comb ranging system by using a numerical simulation method.

    PubMed

    Wu, Guanhao; Xiong, Shilin; Ni, Kai; Zhu, Zebin; Zhou, Qian

    2015-12-14

    Dual-comb system parameters have significant impacts on the ranging accuracy. We present a theoretical model and a numerical simulation method for the parameter optimization of a dual-comb ranging system. With this method we investigate the impacts of repetition rate difference, repetition rate, and carrier-envelope-offset frequency on the ranging accuracy. Firstly, the simulation results suggest a series of discrete zones of repetition rate difference in an optimal range, which are consistent with the experimental results. Secondly, the simulation results of the repetition rate indicate that a higher repetition rate is very favorable to improve the ranging accuracy. Finally, the simulation results suggest a series of discrete optimal ranges of the carrier-envelope-offset frequency for the dual-comb system. The simulated results were verified by our experiments.

  4. Motion and ranging sensor system for through-the-wall surveillance system

    NASA Astrophysics Data System (ADS)

    Black, Jeffrey D.

    2002-08-01

    A portable Through-the-Wall Surveillance System is being developed for law enforcement, counter-terrorism, and military use. The Motion and Ranging Sensor is a radar that operates in a frequency band that allows for surveillance penetration of most non-metallic walls. Changes in the sensed radar returns are analyzed to detect the human motion that would typically be present during a hostage or barricaded suspect scenario. The system consists of a Sensor Unit, a handheld Remote Display Unit, and an optional laptop computer Command Display Console. All units are battery powered and a wireless link provides command and data communication between units. The Sensor Unit is deployed close to the wall or door through which the surveillance is to occur. After deploying the sensor the operator may move freely as required by the scenario. Up to five Sensor Units may be deployed at a single location. A software upgrade to the Command Display Console is also being developed. This software upgrade will combine the motion detected by multiple Sensor Units and determine and track the location of detected motion in two dimensions.

  5. Optimizing the performance of modulated pulse laser systems for imaging and ranging applications

    NASA Astrophysics Data System (ADS)

    Mullen, L.; Lee, R.; Illig, D.

    2017-05-01

    Blue-green laser systems are being developed for optical imaging and ranging in the underwater environment. The imaging application requires high range resolution to distinguish between multiple targets in the scene or between multiple target features, while the ranging application benefits from measurements with high range accuracy. The group at the Naval Air Warfare Center Aircraft Division (NAWCAD) in Patuxent River, MD has been investigating the merging of wideband radar modulation schemes with a pulsed laser system for underwater imaging and ranging applications. For the imaging application, the narrow peak produced by pulse compression at the receiver offers enhanced range resolution relative to traditional short pulse approaches. For ranging, the selection of modulation frequency bands approaching 1GHz provides backscatter and forward scatter suppression and enhanced range accuracy. Both passband and baseband digital processing have been applied to data collected in laboratory water tank experiments. The results have shown that the choice of processing scheme has a significant impact on optimizing the performance of modulated pulse laser systems for either imaging or ranging applications. These different processing schemes will be discussed, and results showing the effect of the processing schemes for imaging and ranging will be presented.

  6. OPO-laser system for atmospheric sounding in the mid-IR range

    NASA Astrophysics Data System (ADS)

    Romanovskii, O. A.; Kharchenko, O. V.; Kondratyuk, N. V.; Protasenya, A. L.; Shumskii, V. K.; Sadovnikov, S. A.; Yakovlev, S. V.

    2015-11-01

    A laser system is designed that provides for tunable generation of nanosecond radiation pulses in the 3-4 μm range. Optical block-diagram and specifications of the system are presented. The laser system as a part of a differential absorption lidar designed can be used for remote control of pollutant concentrations along surface atmospheric paths.

  7. Wide field of view laser beacon system for three dimensional aircraft range measurements

    NASA Technical Reports Server (NTRS)

    Wong, E. Y.

    1982-01-01

    A system that measures accurately the distance from an aircraft to a helicoper for rotor noise flight testing was developed. The system measures the range and angles between two aircraft using laser optics. This system can be applied in collision avoidance, robotics and other measurement critical tasks.

  8. Storage Viability and Optimization Web Service

    SciTech Connect

    Stadler, Michael; Marnay, Christ; Lai, Judy; Siddiqui, Afzal; Limpaitoon, Tanachai; Phan, Trucy; Megel, Olivier; Chang, Jessica; DeForest, Nicholas

    2010-10-11

    Non-residential sectors offer many promising applications for electrical storage (batteries) and photovoltaics (PVs). However, choosing and operating storage under complex tariff structures poses a daunting technical and economic problem that may discourage potential customers and result in lost carbon and economic savings. Equipment vendors are unlikely to provide adequate environmental analysis or unbiased economic results to potential clients, and are even less likely to completely describe the robustness of choices in the face of changing fuel prices and tariffs. Given these considerations, researchers at Lawrence Berkeley National Laboratory (LBNL) have designed the Storage Viability and Optimization Web Service (SVOW): a tool that helps building owners, operators and managers to decide if storage technologies and PVs merit deeper analysis. SVOW is an open access, web-based energy storage and PV analysis calculator, accessible by secure remote login. Upon first login, the user sees an overview of the parameters: load profile, tariff, technologies, and solar radiation location. Each parameter has a pull-down list of possible predefined inputs and users may upload their own as necessary. Since the non-residential sectors encompass a broad range of facilities with fundamentally different characteristics, the tool starts by asking the users to select a load profile from a limited cohort group of example facilities. The example facilities are categorized according to their North American Industry Classification System (NAICS) code. After the load profile selection, users select a predefined tariff or use the widget to create their own. The technologies and solar radiation menus operate in a similar fashion. After these four parameters have been inputted, the users have to select an optimization setting as well as an optimization objective. The analytic engine of SVOW is LBNL?s Distributed Energy Resources Customer Adoption Model (DER-CAM), which is a mixed

  9. Ultra-wide Range Gamma Detector System for Search and Locate Operations

    SciTech Connect

    Odell, D. Mackenzie Odell; Harpring, Larry J.; Moore, Frank S. Jr.; French, Phillip J.; Gordon, John R.

    2005-10-26

    Collecting debris samples following a nuclear event requires that operations be conducted from a considerable stand-off distance. An ultra-wide range gamma detector system has been constructed to accomplish both long range radiation search and close range hot sample collection functions. Constructed and tested on a REMOTEC Andros platform, the system has demonstrated reliable operation over six orders of magnitude of gamma dose from 100's of uR/hr to over 100 R/hr. Functional elements include a remotely controlled variable collimator assembly, a NaI(Tl)/photomultiplier tube detector, a proprietary digital radiation instrument, a coaxially mounted video camera, a digital compass, and both local and remote control computers with a user interface designed for long range operations. Long range sensitivity and target location, as well as close range sample selection performance are presented.

  10. Design and simulation of a mixer and phase difference measuring circuitry for laser range finding systems

    NASA Astrophysics Data System (ADS)

    Liu, Guili; Wang, Yanlin; Liu, Gang

    2006-11-01

    This article focuses on the circuit implementation of a mixer and phase difference measurement for laser range finding systems. It will introduce simply the principle of the laser range finding system, which is the basis of the electronic circuitry design. The modulated laser lights of two different frequencies are mixed and the phase difference is detected in order to measure the range. The method of measuring the range is to use the mixer and the phase difference detector. The new and high precision IC that has a high quality makes the circuit simple and reliable. The circuit of the mixer and the phase difference detector for laser range finding systems is designed using AD608 and AD8302 chips.

  11. Influence of range-gated intensifiers on underwater imaging system SNR

    NASA Astrophysics Data System (ADS)

    Wang, Xia; Hu, Ling; Zhi, Qiang; Chen, Zhen-yue; Jin, Wei-qi

    2013-08-01

    Range-gated technology has been a hot research field in recent years due to its high effective back scattering eliminating. As a result, it can enhance the contrast between a target and its background and extent the working distance of the imaging system. The underwater imaging system is required to have the ability to image in low light level conditions, as well as the ability to eliminate the back scattering effect, which means that the receiver has to be high-speed external trigger function, high resolution, high sensitivity, low noise, higher gain dynamic range. When it comes to an intensifier, the noise characteristics directly restrict the observation effect and range of the imaging system. The background noise may decrease the image contrast and sharpness, even covering the signal making it impossible to recognize the target. So it is quite important to investigate the noise characteristics of intensifiers. SNR is an important parameter reflecting the noise features of a system. Through the use of underwater laser range-gated imaging prediction model, and according to the linear SNR system theory, the gated imaging noise performance of the present market adopted super second generation and generation Ⅲ intensifiers were theoretically analyzed. Based on the active laser underwater range-gated imaging model, the effect to the system by gated intensifiers and the relationship between the system SNR and MTF were studied. Through theoretical and simulation analysis to the image intensifier background noise and SNR, the different influence on system SNR by super second generation and generation Ⅲ ICCD was obtained. Range-gated system SNR formula was put forward, and compared the different effect influence on the system by using two kind of ICCDs was compared. According to the matlab simulation, a detailed analysis was carried out theoretically. All the work in this paper lays a theoretical foundation to further eliminating back scattering effect, improving

  12. 26 CFR 12.4 - Election of Class Life Asset Depreciation Range System (ADR).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 14 2010-04-01 2010-04-01 false Election of Class Life Asset Depreciation Range... Election of Class Life Asset Depreciation Range System (ADR). (a) Elections filed before February 1, 1972... tax return in accordance with § 1.167(a)-11 of this chapter (relating to depreciation allowances...

  13. Early experience with a highly mobile Lageos ranging system. [satellite tracking

    NASA Technical Reports Server (NTRS)

    Silverberg, E. C.; Dittmar, D.; Eanes, R.; Ricklefs, R. L.

    1981-01-01

    Two portions of the University of Texas Transportable Laser Ranging System (TLRS) are presented: the beam director and the burst mode single photon laser ranging system. The system, optimized for the Lageos target, has satellite track rates varying from approximately 1800 arcsec per sec on low targets to a few arcsec per sec on the highest. Using full aperture, approximately 3 millijoules of laser power per shot can be transmitted without exceeding the eye damage threshold, and a beam divergence of less than 30 arcsec is dictated by these parameters. Position loop response is optimized, and the instrument is capable of tracking the satellite from nearly any firm, flat position. The laser ranging system uses a multiple pulse laser, and power restrictions result in an average return of less than one photoelectron per shot. The use of a simple laser for ranging has virtually eliminated the high percentage of down time.

  14. Upgrading and performance of the SAO laser ranging system in Matera

    NASA Technical Reports Server (NTRS)

    Maddox, J.; Pearlman, M.; Throp, J.; Wohn, J.

    1983-01-01

    The performance of the SAO lasers was improved considerably in terms of accuracy, range noise, data yield, and reliability. With the narrower laser pulse (2.5-3.0 nsec) and a new analog pulse processing system, the systematic range errors were reduced to 3-5 cm and range noise has been reduced to 5-15 cm on low satellites and 10-18 cm on Lageos. Pulse repetition rate was increased to 30 ppm and considerable improvement has been made in signal-to-noise ratio by using a 3 Angstrom interference filter and by reducing the range gate window down to 200-400 nsec. The first upgraded system was installed in Arequipa, Peru in the spring of 1982. The second upgraded system is now in operation in Matera, Italy. The third system is expected to be installed in Israel during 1984.

  15. Unifying latitudinal gradients in range size and richness across marine and terrestrial systems

    PubMed Central

    Tomašových, Adam; Kennedy, Jonathan D.; Betzner, Tristan J.; Kuehnle, Nicole Bitler; Edie, Stewart; Kim, Sora; Supriya, K.; White, Alexander E.; Rahbek, Carsten; Huang, Shan; Price, Trevor D.; Jablonski, David

    2016-01-01

    Many marine and terrestrial clades show similar latitudinal gradients in species richness, but opposite gradients in range size—on land, ranges are the smallest in the tropics, whereas in the sea, ranges are the largest in the tropics. Therefore, richness gradients in marine and terrestrial systems do not arise from a shared latitudinal arrangement of species range sizes. Comparing terrestrial birds and marine bivalves, we find that gradients in range size are concordant at the level of genera. Here, both groups show a nested pattern in which narrow-ranging genera are confined to the tropics and broad-ranging genera extend across much of the gradient. We find that (i) genus range size and its variation with latitude is closely associated with per-genus species richness and (ii) broad-ranging genera contain more species both within and outside of the tropics when compared with tropical- or temperate-only genera. Within-genus species diversification thus promotes genus expansion to novel latitudes. Despite underlying differences in the species range-size gradients, species-rich genera are more likely to produce a descendant that extends its range relative to the ancestor's range. These results unify species richness gradients with those of genera, implying that birds and bivalves share similar latitudinal dynamics in net species diversification. PMID:27147094

  16. FAST TRACK COMMUNICATION: Current fluctuations in stochastic systems with long-range memory

    NASA Astrophysics Data System (ADS)

    Harris, R. J.; Touchette, H.

    2009-08-01

    We propose a method to calculate the large deviations of current fluctuations in a class of stochastic particle systems with history-dependent rates. Long-range temporal correlations are seen to alter the speed of the large deviation function in analogy with long-range spatial correlations in equilibrium systems. We give some illuminating examples and discuss the applicability of the Gallavotti-Cohen fluctuation theorem.

  17. p53 induction and cell viability modulation by genotoxic individual chemicals and mixtures.

    PubMed

    Di Paolo, Carolina; Müller, Yvonne; Thalmann, Beat; Hollert, Henner; Seiler, Thomas-Benjamin

    2017-03-16

    The binding of the p53 tumor suppression protein to DNA response elements after genotoxic stress can be quantified by cell-based reporter gene assays as a DNA damage endpoint. Currently, bioassay evaluation of environmental samples requires further knowledge on p53 induction by chemical mixtures and on cytotoxicity interference with p53 induction analysis for proper interpretation of results. We investigated the effects of genotoxic pharmaceuticals (actinomycin D, cyclophosphamide) and nitroaromatic compounds (4-nitroquinoline 1-oxide, 3-nitrobenzanthrone) on p53 induction and cell viability using a reporter gene and a colorimetric assay, respectively. Individual exposures were conducted in the absence or presence of metabolic activation system, while binary and tertiary mixtures were tested in its absence only. Cell viability reduction tended to present direct correlation with p53 induction, and induction peaks occurred mainly at chemical concentrations causing cell viability below 80%. Mixtures presented in general good agreement between predicted and measured p53 induction factors at lower concentrations, while higher chemical concentrations gave lower values than expected. Cytotoxicity evaluation supported the selection of concentration ranges for the p53 assay and the interpretation of its results. The often used 80% viability threshold as a basis to select the maximum test concentration for cell-based assays was not adequate for p53 induction assessment. Instead, concentrations causing up to 50% cell viability reduction should be evaluated in order to identify the lowest observed effect concentration and peak values following meaningful p53 induction.

  18. Differences in pollen viability in relation to different deceptive pollination strategies in Mediterranean orchids

    PubMed Central

    Bellusci, Francesca; Musacchio, Aldo; Stabile, Rossella; Pellegrino, Giuseppe

    2010-01-01

    Background and Aims To date, current research involving pollen viability has been evaluated in a relatively low number of orchid species. In the present study, we focused on five related Mediterranean orchid genera (Anacamptis, Orchis, Dactylorhiza, Ophrys and Serapias) that are characterized by different types of deceptive pollination. Methods The in vitro germination ability of increasingly aged pollinaria of eight food-, seven sexually and two shelter-deceptive species was evaluated. Pollination experiments on two food-, one sexually and one shelter-deceptive species were also performed and the percentage of embryonate seeds derived from the increasingly aged pollinaria was checked. Key Results All of the examined species showed long-term viabilities (=50 % pollen tube growth) that ranged from 8 to 35 d. Species with the same deceptive pollination strategies exhibited the same pollen viability trends. Interestingly, pollen viabilities of species groups with different deception types have shown significant differences, with sexually and shelter- deceptive species exhibiting a shorter life span than food-deceptive species. Conclusions This study confirms the prolonged germination and fertilization capacities of orchid pollinaria, and to our knowledge is the first report demonstrating a clear relationship between pollen viability and pollination system. It is proposed that this relationship is attributed to the different types of reproductive barriers, pre- or post-zygotic, that characterixe Ophrys and Serapias and the food-deceptive species, respectively. PMID:20716575

  19. A solid-state microwave-range self-oscillating chaotic system with a simplified structure

    NASA Astrophysics Data System (ADS)

    Maksimov, N. A.; Panas, A. I.

    2017-02-01

    A solid-state self-oscillating system that provides generation of ultra-wideband chaotic signals in the microwave range has been proposed, implemented, and studied. The system has a simple structure comprising an active element (bipolar transistor) and a single reactive element (inductance). An experimental study of bifurcation phenomena and typical oscillation modes in the system has been carried out. The energy efficiency of the system and the possibility of its implementation in the form of a chip structure are analyzed.

  20. Task path planning, scheduling and learning for free-ranging robot systems

    NASA Technical Reports Server (NTRS)

    Wakefield, G. Steve

    1987-01-01

    The development of robotics applications for space operations is often restricted by the limited movement available to guided robots. Free ranging robots can offer greater flexibility than physically guided robots in these applications. Presented here is an object oriented approach to path planning and task scheduling for free-ranging robots that allows the dynamic determination of paths based on the current environment. The system also provides task learning for repetitive jobs. This approach provides a basis for the design of free-ranging robot systems which are adaptable to various environments and tasks.

  1. Surprises from quenches in long-range-interacting systems: temperature inversion and cooling

    NASA Astrophysics Data System (ADS)

    Gupta, Shamik; Casetti, Lapo

    2016-10-01

    What happens when one of the parameters governing the dynamics of a long-range interacting system of particles in thermal equilibrium is abruptly changed (quenched) to a different value? While a short-range system, under the same conditions, will relax in time to a new thermal equilibrium with a uniform temperature across the system, a long-range system shows a fast relaxation to a non-equilibrium quasistationary state (QSS). The lifetime of such an off-equilibrium state diverges with the system size, and the temperature is non-uniform across the system. Quite surprisingly, the density profile in the QSS obtained after the quench is anticorrelated with the temperature profile in space, thus exhibiting the phenomenon of temperature inversion: denser regions are colder than sparser ones. We illustrate with extensive molecular dynamics simulations the ubiquity of this scenario in a prototypical long-range interacting system subject to a variety of quenching protocols, and in a model that mimics an experimental setup of atoms interacting with light in an optical cavity. We further demonstrate how a procedure of iterative quenching combined with filtering out the high-energy particles in the system may be employed to cool the system. Temperature inversion is observed in nature in some astrophysical settings; our results imply that such a phenomenon should be observable, and could even be exploitable to advantage, also in controlled laboratory experiments.

  2. Development of the circuit system in high frequency satellite laser ranging equipment based on FPGA

    NASA Astrophysics Data System (ADS)

    Chen, Chong; Fan, Chunbo; Li, Zhenwei; Zhao, You

    2008-12-01

    High frequency, as well as automation and day light ranging, is a signify feature of new generation Satellite Laser Ranging (SLR) systems. In spite of increase the quantity of observation data, the high frequency SLR can also significantly improve the SP and NP precision. These trends of SLR technology lead to new requirement of control circuit. In this paper, an implementation of control circuit in single FPGA chip was present. SOPC (system on programmable chip) system was proposed to solve these problems. To realize the system, a control circuit custom component was designed and simulated by us. Then, the component was integrated into a SOPC system. Cooperated with software, the circuit has the ability to control the SLR system running at high frequency. Finally, the system was simulated in the Quartus software and NIOS IDE provided by Altera and implemented in an Altera EP1S10 development kit.

  3. The optical detection in turbid water by range-gated imaging system with HPRF laser

    NASA Astrophysics Data System (ADS)

    Hua, Liang-hong; Han, Hong-wei; Zhang, Xiao-hui

    2015-10-01

    In the field of underwater sensing, the rang-gated imaging based on the principle of "time slice" is an effective way to suppress backscatter and improve operating distance. In this paper, a kind of underwater range-gated imaging system which selects the LD end-pumped solid laser as the illuminator is described. Comparing to the traditional ones using the lamp-pumped Nd: YAG laser, the prime characteristics of the new designed underwater range-gated imaging system lie in the dramatic dropping of single pulse energy and the dramatic increasing of pulse repetition frequency, and the resultant change of echo receiving pattern throughout the image formation. The advantage and disadvantage of the change is first analysed in this paper, and then the underwater range-gated imaging system with high pulse repetition frequency (HPRF) laser is introduced. Finally, the experiment results in the indoor tank and the corresponding analysis is provided.

  4. Economic viability of anaerobic digestion

    SciTech Connect

    Wellinger, A.

    1996-01-01

    The industrial application of anaerobic digestion is a relatively new, yet proven waste treatment technology. Anaerobic digestion reduces and upgrades organic waste, and is a good way to control air pollution as it reduces methane and nitrous gas emissions. For environmental and energy considerations, anaerobic digestion is a nearly perfect waste treatment process. However, its economic viability is still in question. A number of parameters - type of waste (solid or liquid), digester system, facility size, product quality and end use, environmental requirements, cost of alternative treatments (including labor), and interest rates - define the investment and operating costs of an anaerobic digestion facility. Therefore, identical facilities that treat the same amount and type of waste may, depending on location, legislation, and end product characteristics, reveal radically different costs. A good approach for evaluating the economics of anaerobic digestion is to compare it to treatment techniques such as aeration or conventional sewage treatment (for industrial wastewater), or composting and incineration (for solid organic waste). For example, the cost (per ton of waste) of in-vessel composting with biofilters is somewhat higher than that of anaerobic digestion, but the investment costs 1 1/2 to 2 times more than either composting or anaerobic digestion. Two distinct advantages of anaerobic digestion are: (1) it requires less land than either composting or incinerating, which translates into lower costs and milder environmental and community impacts (especially in densely populated areas); and (2) it produces net energy, which can be used to operate the facility or sold to nearby industries.

  5. Design and implementation of control system for range-gated underwater laser imaging

    NASA Astrophysics Data System (ADS)

    Ge, Wei-Long; Zhang, Xiao-Hui; Han, Hong-Wei; Hua, Liang-Hong

    2011-11-01

    There is currently considerable in developing underwater target detection, the underwater imaging system can be divided into active imaging system and passive system. The main feature of the active imaging system is that they use light sources to illuminate the targets and collect the reflection from targets. The advantages of active imaging system over passive imaging systems are high contrast and without the affection of environment sources. In this article, a range-gated underwater laser imaging system is built, which consists of laser illumination system, photoelectric imaging system and control system. The laser illumination system includes a light-pumped solid state doubled ND-YAG laser(532nm) which laser power and frequency can be adjusted and an optics expanding system of variable ratio. The photoelectric imaging system includes a gated Intensified CCD(ICCD) cameras which ICCD scheduling, gate width, delay time and gain can be adjusted and a optics received system of variable ratio. In order to acquire effectual target image using range-gated underwater laser imaging system, appropriate control parameters that include laser power and frequency, ICCD scheduling, gate width, delay time and gain, optics expanding system ratio and optics received system ratio must be given accurately. A control system which used C8051F320 and C8051F040 (MCU) as the core is designed, the control system can effectively control seven parameters that given above. The construction of software and hardware of the control system is introduced. And target image of underwater distance 25 m and 40m is given, Experimental results showed that the control system has high control precision, safe and stable operation and good speed adjusting performance can be achieved. It can be satisfied to apply to underwater target detection.

  6. Design and implementation of control system for range-gated underwater laser imaging

    NASA Astrophysics Data System (ADS)

    Ge, Wei-long; Zhang, Xiao-hui; Han, Hong-wei; Hua, Liang-hong

    2012-01-01

    There is currently considerable in developing underwater target detection, the underwater imaging system can be divided into active imaging system and passive system. The main feature of the active imaging system is that they use light sources to illuminate the targets and collect the reflection from targets. The advantages of active imaging system over passive imaging systems are high contrast and without the affection of environment sources. In this article, a range-gated underwater laser imaging system is built, which consists of laser illumination system, photoelectric imaging system and control system. The laser illumination system includes a light-pumped solid state doubled ND-YAG laser(532nm) which laser power and frequency can be adjusted and an optics expanding system of variable ratio. The photoelectric imaging system includes a gated Intensified CCD(ICCD) cameras which ICCD scheduling, gate width, delay time and gain can be adjusted and a optics received system of variable ratio. In order to acquire effectual target image using range-gated underwater laser imaging system, appropriate control parameters that include laser power and frequency, ICCD scheduling, gate width, delay time and gain, optics expanding system ratio and optics received system ratio must be given accurately. A control system which used C8051F320 and C8051F040 (MCU) as the core is designed, the control system can effectively control seven parameters that given above. The construction of software and hardware of the control system is introduced. And target image of underwater distance 25 m and 40m is given, Experimental results showed that the control system has high control precision, safe and stable operation and good speed adjusting performance can be achieved. It can be satisfied to apply to underwater target detection.

  7. Ultraviolet laser-based communication system for short-range tactical applications

    NASA Astrophysics Data System (ADS)

    Charles, Barry; Hughes, Bill; Erickson, Andrew; Wilkins, Jay; Teppo, Edward A.

    1994-06-01

    Solar blind ultraviolet communication techniques have promise to address the military's needs for short range applications where non-line-of-sight and a low probability of interception and detection is required. This paper addresses the general requirements for these systems and discusses an example system developed using a compact quadrupled Nd:YAG laser.

  8. TOPEX orbit determination using GPS signals plus a sidetone ranging system

    NASA Technical Reports Server (NTRS)

    Bender, P. L.; Larden, D. R.

    1982-01-01

    The GPS orbit determination was studied to see how well the radial coordinate for altimeter satellites such as TOPEX could be found by on board measurements of GPS signals, including the reconstructed carrier phase. The inclusion on altimeter satellites of an additional high accuracy tracking system is recommended. It is suggested that a sidetone ranging system is used in conjunction with TRANET 2 beacons.

  9. A long range transmission system communication plan for ComEd of Chicago 1995 to 2000

    SciTech Connect

    Casanova, R.; Gerleve, F.J.

    1995-10-01

    The design of a telecommunication fiber optical network serving ComEd`s commercial centers and generation stations is described. A long range communication plan is presented describing a migration of transmission substation protection, monitoring and control from an analog system over power line carrier, microwave, and leased phone lines to a digital system using an optimum mix of communication channels including fiber.

  10. Design and performance simulations for an airborne DIAL system for long-range remote sensing applications

    NASA Astrophysics Data System (ADS)

    Dowling, James A.; Kelly, Brian T.; Gonglewski, John D.; Fox, Marsha J.; Shilko, Michael L.; Higdon, Noah S.; Highland, Ronald G.; Senft, Daniel C.; Dean, David R.; Blackburn, John P.; Pierrottet, Diego F.

    1997-01-01

    The U.S. Air Force Phillips Laboratory is evaluating the feasibility of long-standoff-range remote sensing of gaseous species present in trace amounts in the atmosphere. To date, the Phillips Laboratory program has been concerned with the preliminary design and performance analysis of a commercially available CO(subscript 2) laser-based DIAL system operating from mountain-top-observatory and airborne platform and more recently with long-range ground testing using a 21.8 km slant path from 3.05 km ASL to sea level as the initial steps in the design and development of an airborne system capability. Straightforward scaling of the performance of a near-term technology direct-detection LIDAR system with propagation range to a topographic target and with the average atmospheric absorption coefficient along the path has been performed. Results indicate that useful airborne operation of such a system should be possible for slant path ranges between 20 km and 50 km, depending upon atmospheric transmission at the operating wavelengths of the (superscript 13)C(superscript 16)O(subscript 2) source. This paper describes the design of the airborne system which will be deployed on the Phillips Laboratory NC-135 research aircraft for DIAL system performance tests at slant ranges of 20 km to 50 km, scheduled for the near future. Performance simulations for the airborne tests will be presented and related to performance obtained during initial ground-based tests.

  11. Loosely Coupled GPS-Aided Inertial Navigation System for Range Safety

    NASA Technical Reports Server (NTRS)

    Heatwole, Scott; Lanzi, Raymond J.

    2010-01-01

    The Autonomous Flight Safety System (AFSS) aims to replace the human element of range safety operations, as well as reduce reliance on expensive, downrange assets for launches of expendable launch vehicles (ELVs). The system consists of multiple navigation sensors and flight computers that provide a highly reliable platform. It is designed to ensure that single-event failures in a flight computer or sensor will not bring down the whole system. The flight computer uses a rules-based structure derived from range safety requirements to make decisions whether or not to destroy the rocket.

  12. 110 °C range athermalization of wavefront coding infrared imaging systems

    NASA Astrophysics Data System (ADS)

    Feng, Bin; Shi, Zelin; Chang, Zheng; Liu, Haizheng; Zhao, Yaohong

    2017-09-01

    110 °C range athermalization is significant but difficult for designing infrared imaging systems. Our wavefront coding athermalized infrared imaging system adopts an optical phase mask with less manufacturing errors and a decoding method based on shrinkage function. The qualitative experiments prove that our wavefront coding athermalized infrared imaging system has three prominent merits: (1) working well over a temperature range of 110 °C; (2) extending the focal depth up to 15.2 times; (3) achieving a decoded image being approximate to its corresponding in-focus infrared image, with a mean structural similarity index (MSSIM) value greater than 0.85.

  13. Technical Note: Range verification system using edge detection method for a scintillator and a CCD camera system

    SciTech Connect

    Saotome, Naoya Furukawa, Takuji; Hara, Yousuke; Mizushima, Kota; Tansho, Ryohei; Saraya, Yuichi; Shirai, Toshiyuki; Noda, Koji

    2016-04-15

    Purpose: Three-dimensional irradiation with a scanned carbon-ion beam has been performed from 2011 at the authors’ facility. The authors have developed the rotating-gantry equipped with the scanning irradiation system. The number of combinations of beam properties to measure for the commissioning is more than 7200, i.e., 201 energy steps, 3 intensities, and 12 gantry angles. To compress the commissioning time, quick and simple range verification system is required. In this work, the authors develop a quick range verification system using scintillator and charge-coupled device (CCD) camera and estimate the accuracy of the range verification. Methods: A cylindrical plastic scintillator block and a CCD camera were installed on the black box. The optical spatial resolution of the system is 0.2 mm/pixel. The camera control system was connected and communicates with the measurement system that is part of the scanning system. The range was determined by image processing. Reference range for each energy beam was determined by a difference of Gaussian (DOG) method and the 80% of distal dose of the depth-dose distribution that were measured by a large parallel-plate ionization chamber. The authors compared a threshold method and a DOG method. Results: The authors found that the edge detection method (i.e., the DOG method) is best for the range detection. The accuracy of range detection using this system is within 0.2 mm, and the reproducibility of the same energy measurement is within 0.1 mm without setup error. Conclusions: The results of this study demonstrate that the authors’ range check system is capable of quick and easy range verification with sufficient accuracy.

  14. Effects of random path fluctuations on the accuracy of laser ranging systems.

    PubMed

    Gardner, C S

    1976-10-01

    The effects of turbulence induced pathlength fluctuations on the accuracy of single color and two color laser ranging systems are examined. Correlation and structure functions for the path deviations are derived using several proposed models for the variation of C(n)(2) with altitude. For single color systems, random pathlength fluctuations can limit the accuracy of a range measurement to a few centimeters when the turbulence is strong (C(n)(2) ~ 10(-13) m(-2/3)), and the effective propagation path is long (>10 km). Two color systems can partially correct for the random path fluctuations so that in most cases their accuracy is limited to a few millimeters. However, at low elevation angles for satellite ranging (<20 degrees ) and over long horizontal paths, two color systems can also have errors approaching a few centimeters.

  15. Laser-ranging scanning system to observe topographical deformations of volcanoes.

    PubMed

    Aoki, T; Takabe, M; Mizutani, K; Itabe, T

    1997-02-20

    We have developed a laser-ranging system to observe the topographical structure of volcanoes. This system can be used to measure the distance to a target by a laser and shows the three-dimensional topographical structure of a volcano with an accuracy of 30 cm. This accuracy is greater than that of a typical laser-ranging system that uses a corner-cube reflector as a target because the reflected light jitters as a result of inclination and unevenness of the target ground surface. However, this laser-ranging system is useful for detecting deformations of topographical features in which placement of a reflector is difficult, such as in volcanic regions.

  16. Effects of cryoprotectants on the viability and activity of freeze dried recombinant yeasts as novel oral drug delivery systems assessed by an artificial digestive system.

    PubMed

    Blanquet, Stéphanie; Garrait, Ghislain; Beyssac, Erick; Perrier, Céline; Denis, Sylvain; Hébrard, Géraldine; Alric, Monique

    2005-09-01

    The aim of this study was to investigate, in a gastric-small intestinal system TIM-1, the effect of cryoprotectants on the survival of freeze-dried Saccharomyces cerevisiae expressing the heterologous P450 73A1 and their ability to convert trans-cinnamic acid into p-coumaric acid. Yeasts were lyophilized in suspensions of trehalose, maltose, lactose, or a milk proteins/trehalose mix. Freeze-dried or native yeasts and trans-cinnamic acid were introduced simultaneously into TIM-1 at the beginning of digestion. Yeast survival rate was evaluated by cell counting in the ileal effluents. P450 73A1 activity was followed by HPLC assay of p-coumaric acid. Freeze-dried yeasts showed high tolerance to digestive conditions. Nevertheless, their survival rate was lower than that of non-dried cells (around 80% whatever the protective agent vs. 96%). The ability of recombinant freeze-dried S. cerevisiae to perform a bioconversion reaction in the digestive tract was shown with all the protectants. The highest trans-cinnamic acid conversion rate (24 vs. 41% for native yeasts) was obtained with the milk proteins/trehalose mix. These results show that freeze-drying might be considered for the pharmaceutical formulation of new drug delivery systems based on orally administered recombinant yeasts and that TIM-1 could be a helpful tool for the pre-screening of oral dosage forms.

  17. Isotope Brayton electric power system for the 500 to 2500 watt range.

    NASA Technical Reports Server (NTRS)

    Macosko, R. P.; Barna, G. J.; Block, H. B.; Ingle, B. D.

    1972-01-01

    An extensive study was conducted at the Lewis Research Center to evaluate an isotope Brayton electric power system for use in the 500 to 2500 W power range. The study emphasized overall system simplicity in order to reduce parasitic power losses and improve system reliability. The study included detailed parametric cycle analysis, conceptual component designs, and evaluation of system packaging. The study has resulted in the selection of a single-loop system (gas) with six major components including one rotating unit. Calculated net system efficiency varies from 23 to 28% over the power range. The use of the Pu-238 heat source being developed for the Multi-Hundred-Watt Radioisotope Thermoelectric Generator program was assumed.

  18. Data acquisition and analysis of range-finding systems for spacing construction

    NASA Technical Reports Server (NTRS)

    Shen, C. N.

    1981-01-01

    For space missions of future, completely autonomous robotic machines will be required to free astronauts from routine chores of equipment maintenance, servicing of faulty systems, etc. and to extend human capabilities in hazardous environments full of cosmic and other harmful radiations. In places of high radiation and uncontrollable ambient illuminations, T.V. camera based vision systems cannot work effectively. However, a vision system utilizing directly measured range information with a time of flight laser rangefinder, can successfully operate under these environments. Such a system will be independent of proper illumination conditions and the interfering effects of intense radiation of all kinds will be eliminated by the tuned input of the laser instrument. Processing the range data according to certain decision, stochastic estimation and heuristic schemes, the laser based vision system will recognize known objects and thus provide sufficient information to the robot's control system which can develop strategies for various objectives.

  19. A Detailed Evaluation of a Laser Triangulation Ranging System for Mobile Robots

    DTIC Science & Technology

    1983-08-01

    A RPI TECHNICAL REPORT MP-82 A DETAILED EVALUATION OF A LASER - TRIANGULATION RANGING SYSTEM FOR MOBILE ROBOTS by Thomas J. Clement Contract MDA-903...ML/MD VISION SYSTEM THEORY............................... 7 2.1 Laser Triangulation......................................... 7 2.1.1 ML/MD Vision...System Accuracy Factors..................10 2.1.2 Detector "Cone of Vision" Problem ..................... 10 2. 1.3 Laser Triangulation Justification

  20. Identification and calibration of one-way delays in satellite laser ranging systems

    NASA Astrophysics Data System (ADS)

    Prochazka, Ivan; Kodet, Jan; Blazej, Josef; Kirchner, Georg; Koidl, Franz; Wang, Peiyuan

    2017-05-01

    We are reporting on identification and calibration of one-way delays in satellite laser ranging systems. Satellite Laser Ranging (SLR) is a standard technique to measure the distance of satellites as a function of time with millimeter precision and a few millimeters accuracy. For one-way laser ranging, laser time transfer ground to space and for bi- and multi-static laser ranging to space objects identification and measurement of system delays related separately to transmitting and receiving parts of the system are needed. The epochs of transmission and reception of optical signals have to be referred to the coordinated time scale with the accuracy reaching one nanosecond level or better for one-way ranging and space debris multi-static ranging. For transponder ranging and laser time transfer an even higher accuracy of 50 ps or better is needed. These accuracy requirements are by several orders of magnitude higher in comparison to standard SLR applications. A new procedure of calibration of one-way delays related to the SLR systems has been developed and tested. The necessary hardware components needed for calibration measurements were designed and developed in a form of a Calibration Device. It consists of a photon counting detector, an epoch timing device and a dedicated signal cable. The signal propagation delays of these components were determined with an accuracy of better than 20 ps. The signal propagation delay stability of the Calibration Device is on a level of units of picoseconds over days of operation. The Calibration Device and calibration procedure were tested in real measurements at the SLR site in Graz, Austria. The time needed to complete a calibration of one-way delays of the SLR system is less than two days. The one-way system delays were determined with the accuracy better than 50 ps. The measurement principle, Calibration Device and the first results are presented.

  1. The Location of Viability Genes within a Testcross Framework.

    PubMed

    Chapco, W

    1972-02-01

    The maximum likelihood method is applied to the problem of estimating the positions and effects of viability genes. Whenever testcross linkage data indicate the presence of differential viability, it is hypothesized that there exists one viability gene between each marker. Estimation is possible only for two-point data since the number of independent expectation expressions is less than the number of parameters for three or more markers. It is pointed out that within the two-point testcross system, it is impossible to distinguish between pleiotropic effects of the marker genes and the effect of a middle viability gene, if existent. The methods outlined will be useful in their application to experiments specifically designed to locate induced viability genes.

  2. A laser ranging system operating at 1036 nm with Geiger-mode silicon avalanche photodiode

    NASA Astrophysics Data System (ADS)

    Wu, Guang; Ren, Min; Liang, Yan; Wang, Zhiyuan; Pan, Haifeng; Zeng, Heping

    2012-09-01

    We demonstrated a laser ranging experiment obtained with a Geiger-mode silicon avalanche photodiode (Si GAPD). The Surface-to-surface resolution of 15 cm was achieved with the technique of time-correlated single-photon counting. In the experiment, a mode-locked Yb-doped fiber laser at 1036 nm was applied, as the detection efficiency at 1036 nm of Si GAPDs is much higher than that at 1064nm which was widely applied in remote sensing. Due to the single-photon detector, the laser ranging system was able to measure the reflected photon pulses at single-photon level. We realized 32- m laser ranging experiment with a 135-mm diameter Newtonian telescope in daylight. And the system could measure the non-cooperated object longer than 11.3 km far away, which was tested through inserting the optical loss. It presented a potential for hundreds-of-kilometer laser ranging at low-light level.

  3. An expert system approach to determination of tropospheric error in microwave ranging

    NASA Astrophysics Data System (ADS)

    Nahvi, M. J.

    1988-03-01

    Tropospheric water vapor delay in microwave ranging may be estimated through surface models. A model which needs no parameter adjustment for location or time, was applied to data of nearly 110,000 radiosonde launches from 1981 to 1983 in 70 worldwide stations of different geographical and climatical conditions. The annual RMS of residual estimation error varied from 4 mm (polar) to 6.7 cm (tropical). Estimation of tropospheric range error may be improved through stratification of synoptic data. Further improvement may be possible if a knowledge-based system containing a relational data-base, rules, and facts is constructed from historical data and the available expertise, and approaches used in expert systems are applied. The usefulness of this concept is illustrated for wet range error on a limited data set. It may be extended to water vapor radiometry and dry range error.

  4. Acute adipocyte viability after third-generation ultrasound-assisted liposuction.

    PubMed

    Schafer, Mark E; Hicok, Kevin C; Mills, Daniel C; Cohen, Steve R; Chao, James J

    2013-07-01

    Although clinical evidence of successful autologous fat transfer (AFT) using third-generation ultrasound-assisted liposuction (UAL) is readily available, no study has quantified adipocyte viability using standardized methods. The authors assess acute adipocyte viability following fat aspiration as a first step in determining the overall efficacy of using third-generation UAL for AFT. Lipoaspirate samples were collected from patients who underwent elective liposuction procedures at multiple surgery centers. Patients with a history of bleeding disorders, diabetes, human immunodeficiency virus, or lipoatrophy disorders were excluded. The UAL system (VASER; Sound Surgical Technologies, Inc, Louisville, Colorado) was set at 60% amplitude in pulsed mode with vacuum aspiration of 15 in Hg or less. Laboratory analysis included free lipid volume, viability via lipolysis and propidium iodide staining, and cytological analysis, including cell surface protein examination and hematoxylin and eosin staining. The lipolysis assay revealed metabolically active adipocytes with a mean (SD) correlative viability of 85.1% (11%). Direct measures of acute viability via propidium iodide staining resulted in a mean (SD) viability measure of 88.7% (3.5%). Both mean values are within the historical range reported from syringe and vacuum-assisted lipoaspiration. Aqueous and lipid contents were favorably reduced after washing and filtering (Puregraft system; Cytori Therapeutics, Inc, San Diego, California). Cellular phenotypes identified were primarily white blood cells or vascular endothelial and vascular associated cells. Adipose tissue acquired via third-generation UAL is viable at harvest and is potentially a suitable source for autologous fat grafts. These results confirm reported clinical successes utilizing third-generation ultrasound lipoaspirate for AFT.

  5. Short-range order and stability in Gd-Ni and Y-Ni systems

    SciTech Connect

    Colinet, C.; Pasturel, A.; Buschow, K.H.J.

    1987-11-01

    We present experimental determinations of the enthalpies of formation of various amorphous and crystalline alloys in the Gd-Ni and Y-Ni systems. For the amorphous alloys, crystallization enthalpy is studied by means of differential scanning calorimetry. The enthalpy effects observed in amorphous alloys point to the occurrence of chemical short-range order. This manifestation is analyzed using microscopic calculations of chemical short-range order based on a tight-binding Hamiltonian.

  6. Prospecting for a Blind Geothermal System Utilizing Geologic and Geophysical Data, Seven Troughs Range, Northwestern Nevada

    NASA Astrophysics Data System (ADS)

    Forson, Corina

    To aid in the discovery and evaluation of blind resources, it is important to utilize geologic, geophysical, and geochemical techniques to find the required elements (e.g., heat source, fluid to transport the heat, and permeability in a reservoir) for geothermal energy production. Based on a regional low resistivity anomaly discovered through a reconnaissance magnetotelluric (MT) survey, detailed geologic mapping, structural analysis, and a 2 m temperature survey were conducted to delineate the most likely areas for blind geothermal activity in the Seven Troughs Range, Nevada. The Seven Troughs Range resides in the northwestern Basin and Range province 190 km northeast of Reno and 50 km northwest of Lovelock in western Nevada. There is no known geothermal system in the area. Mesozoic metasedimentary strata and intrusions dominate the northern and southern parts of the range but are nonconformably overlain by a thick sequence (~ 1.5 km) of Oligocene to Miocene volcanic and volcaniclastic rocks and Quaternary sediments in the central part of the range. The southern part of the range consists of a basement horst block bounded by two major range-front faults, with Holocene fault scarps marking the more prominent fault on the east side of the range. In contrast, several gently to moderately west-tilted fault blocks, with good exposures of the Tertiary volcanic strata and bounded by a series of steeply east-dipping normal faults, characterize the central part of the range. Kinematic analysis of faults in the range and regional relations indicate a west-northwest-trending extension direction. Accordingly, slip and dilation tendency analyses suggest that north-northeast striking faults are the most favorably oriented for reactivation and fluid flow under the current stress field. Two areas in the Seven Troughs Range have a favorable structural setting for generating permeability and channeling geothermal fluids to the near surface: 1) A major right step in the range

  7. A high resolution laser ranging system based on time-correlated single-photon counting technology

    NASA Astrophysics Data System (ADS)

    Yang, Yixin; Wang, Huanqin; Huang, Zhe; Cao, Yangyang; Gui, Huaqiao

    2014-12-01

    Laser ranging has become an important method for both distance measurements and acquisition of threedimensional (3D) images. In this paper, a laser ranging system based on Time-Correlated Single-Photon Counting technology (TCSPC) is developed. A Geiger-mode avalanche photodiode (G-APD), which has the ability of detecting single-photon events, is used to capture the weak light scattered from the long-range target. In order to improve the ranging resolution of TCSPC based measurement system, a high repetition frequency of subnanosecond narrow pulse generator circuit based on the avalanche effect of RF-BJT is designed and applied as the light source. Moreover, some optimized optical light designs have been done to improve the system signal to noise rate (SNR), including using a special aspherical lens as projecting lens, adopting a telephoto camera lens with small view angle and short depth of field before detector. Experimental tests for evaluation of the laser raging system performance are described. As a means of echo signal analysis, three different algorithms have been introduced, in which the cross-correlation algorithm was demonstrated to be the most effective algorithm to determining the round trip time to a target, even based on histograms with a significant amount of background noise photons. It was found that centimeter ranging resolution can be achieved thanks to the use of Time-to-Digital Converter (TDC) with picosecond resolution and the Cross-Correlation algorithm. The proposed laser ranging system has advantages of high range resolution, short response time and simple structure, which was potential applications for 3D object recognition, computer vision, reverse engineering and virtual reality.

  8. Simulation of cow-calf production systems in a range environment: I. Model development.

    PubMed

    Tess, M W; Kolstad, B W

    2000-05-01

    A mathematical computer model of beef cattle production systems was developed at Montana State University. The objective of this report was to describe the rationale and procedures used to simulate animal and system performance. The model was designed to simulate the dynamic relationships among cattle genotype, physiological state, forage quality, and management in range environments. Forage intake, energy and protein metabolism, growth, reproduction, lactation, and changes in chemical body composition are simulated for individual animals over complete life cycles. Expenses driven by animal performance, management decisions, and land resources are tabulated. Several biological and economic measures of system performance can be computed, including ratios of inputs (e.g., DM, CP, ME, dollars) to outputs (e.g., weight, lean), break even prices, and annual gross margin per cow or ranch. Primary uses of the model include the evaluation of system responses to changes in breeding strategies and management in range production/marketing systems.

  9. An LED-array-based range imaging system used for enhancing three-dimensional imaging

    NASA Astrophysics Data System (ADS)

    Wang, Huanqin; Xu, Jun; He, Deyong; Zhao, Tianpeng; Wang, Anting; Ming, Hai; Kong, Deyi

    2010-11-01

    An LED-array-based range imaging system is proposed for three-dimensional (3-D) shape measurement. The range image is obtained by time-division electronic scanning of the LED Time-of-Flight (TOF) range finders in array, and no complex mechanical scanning is needed. By combining with a low cost CCD/CMOS sensor for capturing the twodimensional (2-D) image, the proposed range imaging system can be used to accomplish a high quality 3-D imaging. A sophisticated co-lens optical path is designed to assure the natural registration between the range image and 2-D image. Experimental tests for evaluation of the imaging system performance are described. It was found that the 3-D images can be acquired at a rate of 10 frames per second with a depth resolution better than 5mm in the range of 50 - 1000mm, which is sufficient for many practical applications, including the obstacle detection in robotics, machine automation, 3-D vision, virtual reality games and 3-D video.

  10. Range-separated double-hybrid density-functional theory applied to periodic systems

    SciTech Connect

    Sansone, Giuseppe; Civalleri, Bartolomeo; Maschio, Lorenzo; Usvyat, Denis; Toulouse, Julien; Sharkas, Kamal

    2015-09-14

    Quantum chemistry methods exploiting density-functional approximations for short-range electron-electron interactions and second-order Møller-Plesset (MP2) perturbation theory for long-range electron-electron interactions have been implemented for periodic systems using Gaussian-type basis functions and the local correlation framework. The performance of these range-separated double hybrids has been benchmarked on a significant set of systems including rare-gas, molecular, ionic, and covalent crystals. The use of spin-component-scaled MP2 for the long-range part has been tested as well. The results show that the value of μ = 0.5 bohr{sup −1} for the range-separation parameter usually used for molecular systems is also a reasonable choice for solids. Overall, these range-separated double hybrids provide a good accuracy for binding energies using basis sets of moderate sizes such as cc-pVDZ and aug-cc-pVDZ.

  11. a Pre-Emphasis Technique to Broaden the Usable Frequency Range in Swept-Frequency Systems

    NASA Astrophysics Data System (ADS)

    Gammell, Paul M.; Maruvada, Subha; Liu, Yunbo; Harris, Gerald R.

    2010-02-01

    The usable frequency range of an ultrasonic swept-frequency system can be compromised because of transducer bandwidth limitations or sample frequency response and corresponding signal-to-noise (S/N) considerations. By adding a variable gain amplifier together with an arbitrary waveform generator that is synchronized with the frequency sweep, the dynamic range of the receiver can be accommodated over a wider frequency range. This pre-emphasis approach has been demonstrated for two applications: substitution calibration of hydrophones and attenuation measurements.

  12. Optimizing the dynamic range extension of a radiochromic film dosimetry system

    SciTech Connect

    Devic, Slobodan; Tomic, Nada; Soares, Christopher G.; Podgorsak, Ervin B.

    2009-02-15

    The authors present a radiochromic film dosimetry protocol for a multicolor channel radiochromic film dosimetry system consisting of the external beam therapy (EBT) model GAFCHROMIC film and the Epson Expression 1680 flat-bed document scanner. Instead of extracting only the red color channel, the authors are using all three color channels in the absorption spectrum of the EBT film to extend the dynamic dose range of the radiochromic film dosimetry system. By optimizing the dose range for each color channel, they obtained a system that has both precision and accuracy below 1.5%, and the optimized ranges are 0-4 Gy for the red channel, 4-50 Gy for the green channel, and above 50 Gy for the blue channel.

  13. Optimizing the dynamic range extension of a radiochromic film dosimetry system.

    PubMed

    Devic, Slobodan; Tomic, Nada; Soares, Christopher G; Podgorsak, Ervin B

    2009-02-01

    The authors present a radiochromic film dosimetry protocol for a multicolor channel radiochromic film dosimetry system consisting of the external beam therapy (EBT) model GAFCHROMIC film and the Epson Expression 1680 flat-bed document scanner. Instead of extracting only the red color channel, the authors are using all three color channels in the absorption spectrum of the EBT film to extend the dynamic dose range of the radiochromic film dosimetry system. By optimizing the dose range for each color channel, they obtained a system that has both precision and accuracy below 1.5%, and the optimized ranges are 0-4 Gy for the red channel, 4-50 Gy for the green channel, and above 50 Gy for the blue channel.

  14. Optimal performance receiving ranging system model and realization using TCSPC technique

    NASA Astrophysics Data System (ADS)

    Shen, Shanshan; Chen, Qian; He, Weiji; Zhou, Pin; Gu, Guohua

    2015-10-01

    In this paper, the short dead time detection probability is introduced to the linear SNR model of fixed frequency multipulse accumulation detection system. Monte Carlo simulation is consistent with the theory simulation, which proves that with the increased laser power, the SNR first gets larger quickly and then becomes stable. Then the range standard deviation model is settled and firstly shows that larger dead time brings better range precision, which is consistent with the B. I. Cantor's research. Secondly, Monte Carlo simulation and theory simulation both indicate that with the increased laser power, range precision first enhances and then becomes stable. Experimental results show that based on 500000c/s high background noise, the maximum of SNR can be obtained with emitting laser power at about 400uw at 50ms integrated time. Range precision reaches the optimal level at 6mm. The experimental data show a precision which is always worse than the Monte Carlo simulated results. This arises from the fact that the histograms' jitter is not taking into account and introduced during simulation, whereas the experimental system has approximately 500ps' jitter. The system jitter causes larger time stamp value fluctuation, leading to worse range precision. To sum up, theory and experiment all prove that the optimal performance receiving of SNR and precision is achieved on this multi-pulse accumulation detection system.

  15. Reliability of range-separated hybrid functionals for describing magnetic coupling in molecular systems

    NASA Astrophysics Data System (ADS)

    Rivero, Pablo; Moreira, Ibério de P. R.; Illas, Francesc; Scuseria, Gustavo E.

    2008-11-01

    The performance of the Heyd-Scuseria-Ernzerhorf (HSE) and single parameter long-range corrected Perdew-Burke-Ernzerhorf (LC-ωPBE) range-separated hybrids for predicting magnetic coupling constants has been investigated for a broad set of magnetic molecular systems for which accurate experimental data exist. The set includes the H-He-H model system, two organic diradicals with different magnetic behaviors, and a series of Cu dinuclear complexes with a broad range of magnetic coupling values. Both HSE and LC-ωPBE provide a significant improvement to standard hybrids such as the well-known hybrid Becke-3-parameters exchange with Lee-Yang-Parr correlation (B3LYP) functional. Nevertheless, the performance of these two range-separated hybrid functionals is different: HSE overestimates antiferromagnetic and ferromagnetic interactions in Cu dinuclear complexes (although significantly less than B3LYP), whereas LC-ωPBE treats ferro- and antiferromagnetic couplings on a much more balanced way. The increased accuracy of LC-ωPBE suggests that the inclusion of 100% Hartree-Fock exchange considered in the definition of this long-range corrected hybrid functional has important consequences for an accurate description of exchange and correlation effects on the electronic structure of open shell systems. On the other hand, HSE, which was developed with periodic systems in mind, also performs quite well (and better than B3LYP) thus opening the possibility of magnetic coupling studies in metal oxides and other challenging solids.

  16. Evolution of microbial aerosol behaviour in heating, ventilating and air-conditioning systems--quantification of Staphylococcus epidermidis and Penicillium oxalicum viability.

    PubMed

    Forthomme, A; Andrès, Y; Joubert, A; Simon, X; Duquenne, P; Bemer, D; Le Coq, L

    2013-01-01

    The aim of this study was to develop an experimental set-up and a methodology to uniformly contaminate several filter samples with high concentrations of cultivable bacteria and fungi. An experimental set-up allows contaminating simultaneously up to four filters for range of velocities representative of heating, ventilating and air-conditioning systems. The test aerosol was composed of a microbial consortium of one bacterium (Staphylococcus epidermidis) and one fungus (Penicillium oxalicum) and aerosol generation was performed in wet conditions. Firstly, the experimental set-up was validated in regards to homogeneity of the air flows. The bioaerosol was also characterized in terms of number and particle size distribution using two particle counters: optical particle counter Grimm 1.109 (optical diameters) and TSI APS 3321 (aerodynamic diameters). Moreover, stabilities of the number of particles generated were measured. Finally, concentrations of cultivable microorganisms were measured with BioSamplers (SKC) downstream of the four filters.

  17. Evolution of microbial aerosol behaviour in heating, ventilating and air-conditioning systems--quantification of Staphylococcus epidermidis and Penicillium oxalicum viability.

    PubMed

    Forthomme, A; Andrès, Y; Joubert, A; Simon, X; Duquenne, P; Bemer, D; Le Coq, L

    2012-01-01

    The aim of this study was to develop an experimental set-up and a methodology to uniformly contaminate several filter samples with high concentrations of cultivable bacteria and fungi. An experimental set-up allows contaminating simultaneously up to four filters for range of velocities representative of heating, ventilating and air-conditioning systems. The test aerosol was composed of a microbial consortium of one bacterium (Staphylococcus epidermidis) and one fungus (Penicillium oxalicum) and aerosol generation was performed in wet conditions. Firstly, the experimental set-up was validated in regards to homogeneity of the air flows. The bioaerosol was also characterized in terms of the number and particle size distribution using two particle counters: optical particle counter Grimm 1.109 (optical diameters) and TSI APS 3321 (aerodynamic diameters). Moreover, stabilities of the number of particles generated were measured. Finally, concentrations of cultivable microorganisms were measured with BioSamplers SKC downstream of the four filters.

  18. Early effects of liver regeneration on endocrine pancreas: in vivo change in islet morphology and in vitro assessment of systemic effects on β-cell function and viability in the rat model of two-thirds hepatectomy.

    PubMed

    Moreau, F; Seyfritz, E; Toti, F; Sigrist, S; Bietigier, W; Pinget, M; Kessler, L

    2014-12-01

    Liver and pancreas share key roles in glucose homeostasis. Liver regeneration is associated with systemic modifications and depends especially on pancreatic hormones. The aim of the study was to investigate the role of systemic factors released after two-thirds hepatectomy (2/3H) on early possible consequences of liver regeneration on endocrine pancreas structure and function. The pancreas and serum were harvested 1, 2, or 3 days after 2/3H or sham operation in Lewis rats. The HGF and VEGF serum concentrations and plasma microparticles levels were measured. The fate of endocrine pancreas was examined through islets histomorphometry and function in sham and 2/3H rats. β-Cell line RIN-m5F viability was assessed after 24 h of growth in media supplemented with 10% serum from 2/3H or sham rats instead of FCS. Three days after surgery, the pancreas was heavier in 2/3H compared to sham rats (0.56 vs. 0.40% of body weight, p < 0.05) and the proportion of islets of intermediate size was lower in 2/3H rats (5 vs. 15%, p < 0.05). Compared to Sham, sera obtained 3 days after hepatectomy were more efficient to maintain the viability of RIN-m5F cells (99 vs. 67%, p < 0.01). Three days after surgery, no significant differences in serum HGF, a trend to significant increase in VEGF concentration and a significant increase in microparticles levels, were observed in 2/3H vs. sham rats (9.8 vs. 6.5 nM Phtd Ser Eq., p < 0.05). Liver regeneration is associated with early effects on islets and could influence β-cell viability and function by systemic effect.

  19. Single photon ranging system using two wavelengths laser and analysis of precision

    NASA Astrophysics Data System (ADS)

    Chen, Yunfei; He, Weiji; Miao, Zhuang; Gu, Guohua; Chen, Qian

    2013-09-01

    The laser ranging system based on time correlation single photon counting technology and single photon detector has the feature of high precision and low emergent energy etc. In this paper, we established a single photon laser ranging system that use the supercontinuum laser as light source, and two wavelengths (532nm and 830nm) of echo signal as the stop signal. We propose a new method that is capable to improve the single photon ranging system performance. The method is implemented by using two single-photon detectors to receive respectively the two different wavelength signals at the same time. We extracted the firings of the two detectors triggered by the same laser pulse at the same time and then took mean time of the two firings as the combined detection time-of-flight. The detection by two channels using two wavelengths will effectively improve the detection precision and decrease the false alarm probability. Finally, an experimental single photon ranging system was established. Through a lot of experiments, we got the system precision using both single and two wavelengths and verified the effectiveness of the method.

  20. Pulsed multiwavelength laser ranging system. Ph.D. Thesis - Maryland Univ.

    NASA Technical Reports Server (NTRS)

    Abshire, J. B.

    1982-01-01

    A pulsed multiwavelength laser ranging system for measuring atmospheric delay was built and tested, and its theoretical performance limits were calculated. The system uses a dye modelocked ND:YAG laser, which transmits 70 psec wide pulses simultaneously at 1064, 532, and 355 nm. The differential delay of the 1064 and 355 nm pulses is measured by a specially calibrated waveform digitizer to estimate the dry atmospheric delay. The delay time of the 532 nm pulse is used to measure the target distance. Static crossed field photomultipliers are used as detectors for all wavelengths. Theoretical analysis shows that path curvature and atmospheric turbulence are fundamental limits to the ranging accuracy of both single and multicolor systems operating over horizontal paths. For two color systems, an additional error is caused by the uncertainty in the path averaged water vapor. The standard deviation of the multicolor instrument's timing measurements is directly proportional to the laser pulse width plus photomultiplier jitter divided by the square root of the received photoelectron number. The prototype system's maximum range is km, which is limited by atmospheric and system transmission losses at 355 nm. System signal detection and false alarm calculations are also presented.

  1. A close-range photogrammetric system for 3-D measurements and perspective diagramming in biomechanics.

    PubMed

    Ghosh, S K

    1983-01-01

    Criteria considered in developing a close-range photogrammetric three-dimensional mapping system and its overall performance are discussed. The system consists of a stereophotographic capability of two cameras with synchronized shutters, a stereoplotting instrument with three-dimensional digitizing capability and a Calcomp plotter. Mapping of human knee-bones (femur and tibia) and perspective diagramming for various attitudes of one bone head with regard to the other are illustrated. The system works off-line with respect to the three principal components. The system is fully operational and is considered very efficient with regard to the current needs. Various possibilities are discussed.

  2. Evaluation metrics for range-gated active imaging systems using a Lissajous-type eye pattern.

    PubMed

    Laurenzis, Martin

    2010-04-20

    In this paper a new method to evaluate gated viewing systems and range-gated imaging sequences, using a Lissajous-type eye pattern, is presented. This approach enables the comparison of gated viewing systems and defines clear criteria for depth resolution and depth mapping capabilities of an active imaging system. A distinct parameter can be depicted and sensed within a single chart. Therefore, this approach is a first proposal for an evaluation procedure of gated viewing systems and an enhanced analysis tool in the means of 3D capabilities.

  3. LFR Demonstrator Materials Viability

    SciTech Connect

    Caro, M

    2006-08-02

    Interest in fast reactor development has increased with the Department of Energy's introduction of the Global Nuclear Energy Partnership (GNEP) [1]. The GNEP program plans development of a sodium cooled Advanced Burner Reactor (ABR) that can be used to reduce the amount spent LWR fuel in storage and the number of high level waste sites needed for expansion of nuclear power throughout the world over the 21st century. In addition, the program proposes to make nuclear power more available while reducing the proliferation concerns by revising policies and technology for control of weapons useable materials. This would be accomplished with establishment of new institutional arrangements based on selective siting of reprocessing, enrichment and waste disposal facilities. The program would also implement development of small reactors suitable for use in developing countries or remote regions with small power grids. Over the past several years, under the Department of Energy (DOE) NERI and GEN IV programs research has been conducted on small lead cooled reactors. The Small Secure Transportable Autonomous Reactor (SSTAR) [2] is the most recent version of this type of reactor and research is continuing on it in the GEN IV program in parallel with GNEP. SSTAR is a small (10MWe-100MWe) reactor that is fueled once for life. It complements the GNEP program very well in that it serves one of the world markets not currently addressed by large reactors and its development requirements are similar to those for the ABRs. In particular, the fuel and structural materials for these fast spectrum reactors share common thermal and neutron environments. The coolants, sodium in ABR and lead or lead-bismuth eutectic (LBE) in SSTAR, are the major developmental difference. This report discusses the status of structural materials for fast reactor core and primary system components and selected aspects of their development.

  4. Long-range visible light communication system based on LED collimating lens

    NASA Astrophysics Data System (ADS)

    Chen, Yingcong; Wen, Shangsheng; Wu, Yuxiang; Ren, Yuanyuan; Guan, Weipeng; Zhou, Yunlin

    2016-10-01

    An advanced visible light communication (VLC) system is proposed for long-range VLC, such as marine communication. The design of the system is conducted into two parts. Firstly, we design and optimize a collimating lens for the optical antenna by using Taguchi method. The lighting effects and optical power of the receiving end in different distances are simulated by TracePro software. Then, the long-range VLC channel is reconstructed by integrating the influence of the atmospheric attenuation and frequency response. The performance of the OOK coding VLC system is tested by Matlab software. The results show that: the emitting angle of the optimized collimating lens is 1.7°. By using 1 W LED and collimating lens as an optical antenna, the system can achieve a data rate of 210 Mbit/s at a bit error rate of 10-3 in 90 m.

  5. Analysis of quantum Monte Carlo dynamics for quantum adiabatic evolution in infinite-range spin systems

    NASA Astrophysics Data System (ADS)

    Inoue, Jun-Ichi

    2011-03-01

    We analytically derive deterministic equations of order parameters such as spontaneous magnetization in infinite-range quantum spin systems obeying quantum Monte Carlo dynamics. By means of the Trotter decomposition, we consider the transition probability of Glauber-type dynamics of microscopic states for the corresponding classical system. Under the static approximation, differential equations with respect to macroscopic order parameters are explicitly obtained from the master equation that describes the microscopic-law. We discuss several possible applications of our approach to disordered spin systems for statistical-mechanical informatics. Especially, we argue the ground state searching for infinite-range random spin systems via quantum adiabatic evolution. We were financially supported by Grant-in-Aid for Scientific Research (C) of Japan Society for the Promotion of Science, No. 22500195.

  6. Single-plane versus three-plane methods for relative range error evaluation of medium-range 3D imaging systems

    NASA Astrophysics Data System (ADS)

    MacKinnon, David K.; Cournoyer, Luc; Beraldin, J.-Angelo

    2015-05-01

    Within the context of the ASTM E57 working group WK12373, we compare the two methods that had been initially proposed for calculating the relative range error of medium-range (2 m to 150 m) optical non-contact 3D imaging systems: the first is based on a single plane (single-plane assembly) and the second on an assembly of three mutually non-orthogonal planes (three-plane assembly). Both methods are evaluated for their utility in generating a metric to quantify the relative range error of medium-range optical non-contact 3D imaging systems. We conclude that the three-plane assembly is comparable to the single-plane assembly with regard to quantification of relative range error while eliminating the requirement to isolate the edges of the target plate face.

  7. Studies for determining the optimum propulsion system characteristics for use in a long range transport aircraft

    NASA Technical Reports Server (NTRS)

    Brines, G. L.

    1972-01-01

    A comprehensive evaluation of propulsion systems for the next generation of near-sonic long range transport aircraft indicates that socially responsive noise and emission goals can be achieved within the probable limits of acceptable airplane performance and economics. Technology advances needed in the 1975-1985 time period to support the development of these propulsion systems are identified and discussed. The single most significant result is the low noise, high performance potential of a low tip speed, spaced, two-stage fan.

  8. A regional density distribution based wide dynamic range algorithm for infrared camera systems

    NASA Astrophysics Data System (ADS)

    Park, Gyuhee; Kim, Yongsung; Joung, Shichang; Shin, Sanghoon

    2014-10-01

    Forward Looking InfraRed (FLIR) imaging system has been widely used for both military and civilian purposes. Military applications include target acquisition and tracking, night vision system. Civilian applications include thermal efficiency analysis, short-ranged wireless communication, weather forecasting and other various applications. The dynamic range of FLIR imaging system is larger than one of commercial display. Generally, auto gain controlling and contrast enhancement algorithm are applied to FLIR imaging system. In IR imaging system, histogram equalization and plateau equalization is generally used for contrast enhancement. However, they have no solution about the excessive enhancing when luminance histogram has been distributed in specific narrow region. In this paper, we proposed a Regional Density Distribution based Wide Dynamic Range algorithm for Infrared Camera Systems. Depending on the way of implementation, the result of WDR is quite different. Our approach is single frame type WDR algorithm for enhancing the contrast of both dark and white detail without loss of bins of histogram with real-time processing. The significant change in luminance caused by conventional contrast enhancement methods may introduce luminance saturation and failure in object tracking. Proposed method guarantees both the effective enhancing in contrast and successive object tracking. Moreover, since proposed method does not using multiple images on WDR, computation complexity might be significantly reduced in software / hardware implementation. The experimental results show that proposed method has better performance compared with conventional Contrast enhancement methods.

  9. Laser Ranging in Solar System: Technology Developments and New Science Measurement Capabilities

    NASA Astrophysics Data System (ADS)

    Sun, X.; Smith, D. E.; Zuber, M. T.; Mcgarry, J.; Neumann, G. A.; Mazarico, E.

    2015-12-01

    Laser Ranging has played a major role in geodetic studies of the Earth over the past 40 years. The technique can potentially be used in between planets and spacecrafts within the solar system to advance planetary science. For example, a direct measurement of distances between planets, such as Mars and Venus would make significant improvements in understanding the dynamics of the whole solar system, including the masses of the planets and moons, asteroids and their perturbing interactions, and the gravity field of the Sun. Compared to the conventional radio frequency (RF) tracking systems, laser ranging is potentially more accurate because it is much less sensitive to the transmission media. It is also more efficient because the laser beams are much better focused onto the targets than RF beams. However, existing laser ranging systems are all Earth centric, that is, from ground stations on Earth to orbiting satellites in near Earth orbits or lunar orbit, and to the lunar retro-reflector arrays deployed by the astronauts in the early days of lunar explorations. Several long distance laser ranging experiments have been conducted with the lidar in space, including a two-way laser ranging demonstration between Earth and the Mercury Laser Altimeter (MLA) on the MESSENGER spacecraft over 24 million km, and a one way laser transmission and detection experiment over 80 million km between Earth and the Mars Orbiting Laser Altimeter (MOLA) on the MGS spacecraft in Mars orbit. A one-way laser ranging operation has been carried out continuously from 2009 to 2014 between multiple ground stations to LRO spacecraft in lunar orbit. The Lunar Laser Communication Demonstration (LLCD) on the LADEE mission has demonstrated that a two way laser ranging measurements, including both the Doppler frequency and the phase shift, can be obtained from the subcarrier or the data clocks of a high speed duplex laser communication system. Plans and concepts presently being studied suggest we may be

  10. Universal threshold for the dynamical behavior of lattice systems with long-range interactions.

    PubMed

    Bachelard, Romain; Kastner, Michael

    2013-04-26

    Dynamical properties of lattice systems with long-range pair interactions, decaying like 1/r(α) with the distance r, are investigated, in particular the time scales governing the relaxation to equilibrium. Upon varying the interaction range α, we find evidence for the existence of a threshold at α=d/2, dependent on the spatial dimension d, at which the relaxation behavior changes qualitatively and the corresponding scaling exponents switch to a different regime. Based on analytical as well as numerical observations in systems of vastly differing nature, ranging from quantum to classical, from ferromagnetic to antiferromagnetic, and including a variety of lattice structures, we conjecture this threshold and some of its characteristic properties to be universal.

  11. Slow dynamics in many-body quantum systems with long range interactions

    NASA Astrophysics Data System (ADS)

    Santos, Lea; Perez-Bernal, Francisco

    2016-05-01

    In recent experiments with ion traps the range of the interactions between spins-1/2 can be controlled. In the limit of infinite-range interaction the system may be described by the Lipkin model, which exhibits an excited state quantum phase transition (ESQPT). The latter corresponds to a singularity in the spectrum that occurs at the ground state and propagates to higher energies as the control parameter increases beyond the ground state critical point. We show that the evolution of an initial state with energy close to the ESQPT critical point may be extremely slow. This result is surprising, since the dynamics is usually expected to be very fast in systems with long-range interactions. This behavior is justified with the analysis of the structures of the eigenstates. This work was supported by the NSF Grant No. DMR-1147430.

  12. Small high-speed dynamic target at close range laser active imaging system

    NASA Astrophysics Data System (ADS)

    Yao, Jun; Wang, Du-yue; Zhang, Zheng; Zhang, Yue; Dai, Qin

    2016-11-01

    In the shooting range measuring, all-weather, high speed, unattended, the new concepts such as the remote control is gradually applied. In this paper, a new type of low cost range measurement system, using FPGA + MCU as electronic control system of laser active illumination and high-speed CMOS camera, data to the rear zone by using optical fiber communications, transmission and realizes the remote control of unmanned, due to the low cost of front-end equipment, can be used as consumables replacement at any time, combined with distributed layout principle, can maximum limit close to the measured with mutilate ability goal, thus to achieve the goal of small high-speed dynamic imaging from close range.

  13. Self-organized criticality in glassy spin systems requires long-range interactions

    NASA Astrophysics Data System (ADS)

    Andresen, Juan Carlos; Andrist, Ruben S.; Katzgraber, Helmut G.; Dobrosavljevic, Vladimir; Zimanyi, Gergerly T.

    2013-03-01

    We investigate the conditions required for general spin systems with frustration and disorder to display self-organized criticality, a property which so far has been established in spin models only for the infinite-range Sherringtion-Kirkpatrick Ising spin-glass model [PRL 83, 1034 (1999)]. We study the avalanche and the magnetization jump distribution triggered by an external magnetic field in the short-range Edward-Anderson Ising spin glass for various space dimensions, between 2 and 8. Our numerical results, obtained on systems of unprecedented size, demonstrate that self-organized criticality is recovered only in the strict limit of infinite space dimensions (or equivalently of long-ranged interaction), and is not a generic property of spin-glass models in finite space dimensions.

  14. An underwater ranging system based on photoacoustic effect occurring on target surface

    NASA Astrophysics Data System (ADS)

    Ni, Kai; Hu, Kai; Li, Xinghui; Wang, Lidai; Zhou, Qian; Wang, Xiaohao

    2016-11-01

    In this paper, an underwater ranging system based on photoacoustic effect occurring on target surface is proposed. In this proposal, laser pulse generated by blue-green laser is directly incident on target surface, where the photoacoustic effect occurs and a sound source is formed. And then the sound wave which is also called photoacoustic signal is received by the ultrasonic receiver after passing through water. According to the time delay between transmitting laser and receiving photoacoustic signal, and sound velocity in water, the distance between the target and the ultrasonic receiver can be calculated. Differing from underwater range finding by only laser, this approach can avoid backscattering of laser beam, so easier to implement. Experimental system according to this principle has been constructed to verify the feasibility of this technology. The experimental results showed that a ranging accuracy of 1 mm can be effectively achieved when the target is close to the ultrasonic receiver.

  15. Robust Range Estimation with a Monocular Camera for Vision-Based Forward Collision Warning System

    PubMed Central

    2014-01-01

    We propose a range estimation method for vision-based forward collision warning systems with a monocular camera. To solve the problem of variation of camera pitch angle due to vehicle motion and road inclination, the proposed method estimates virtual horizon from size and position of vehicles in captured image at run-time. The proposed method provides robust results even when road inclination varies continuously on hilly roads or lane markings are not seen on crowded roads. For experiments, a vision-based forward collision warning system has been implemented and the proposed method is evaluated with video clips recorded in highway and urban traffic environments. Virtual horizons estimated by the proposed method are compared with horizons manually identified, and estimated ranges are compared with measured ranges. Experimental results confirm that the proposed method provides robust results both in highway and in urban traffic environments. PMID:24558344

  16. Relative lateration across the Los Angeles basin using a satellite laser ranging system

    NASA Technical Reports Server (NTRS)

    Silverberg, E. C.; Cahill, T.; Dorman, J.

    1982-01-01

    In January of 1981 the Transportable Laser Ranging System (TLRS) developed for NASA by the University of Texas was used to conduct a four-day test of the relative lateration technique. The test evolved making repeated measurements of six lines over the Los Angeles basin varying in distance from 26 to 84 kilometers. Although the raw times-of-flight to the various targets changed typically by 5 parts in 10 to the 6th, their line ratios varied nearly an order of magnitude less. The test suggests that the TLRS or other pulsed laser ranging systems might be able to economically combine Lageos ranging and long baseline horizontal work to survey large areas for accumulating crustal strain.

  17. Bi-Directional Brillouin Optical Time Domain Analyzer System for Long Range Distributed Sensing.

    PubMed

    Guo, Nan; Wang, Liang; Wang, Jie; Jin, Chao; Tam, Hwa-Yaw; Zhang, A Ping; Lu, Chao

    2016-12-16

    We propose and experimentally demonstrate a novel scheme of bi-directional Brillouin time domain analyzer (BD-BOTDA) to extend the sensing range. By deploying two pump-probe pairs at two different wavelengths, the Brillouin frequency shift (BFS) distribution over each half of the whole fiber can be obtained with the simultaneous detection of Brillouin signals in both channels. Compared to the conventional unidirectional BOTDA system of the same sensing range, the proposed BD-BOTDA scheme enables distributed sensing with a performance level comparable to the conventional one with half of the sensing range and a spatial resolution of 2 m, while maintaining the Brillouin signal-to-noise ratio (SNR) and the BFS uncertainty. Based on this technique, we have achieved distributed temperature sensing with a measurement range of 81.9 km fiber at a spatial resolution of 2 m and BFS uncertainty of ~0.44 MHz without introducing any complicated components or schemes.

  18. Bi-Directional Brillouin Optical Time Domain Analyzer System for Long Range Distributed Sensing

    PubMed Central

    Guo, Nan; Wang, Liang; Wang, Jie; Jin, Chao; Tam, Hwa-Yaw; Zhang, A. Ping; Lu, Chao

    2016-01-01

    We propose and experimentally demonstrate a novel scheme of bi-directional Brillouin time domain analyzer (BD-BOTDA) to extend the sensing range. By deploying two pump-probe pairs at two different wavelengths, the Brillouin frequency shift (BFS) distribution over each half of the whole fiber can be obtained with the simultaneous detection of Brillouin signals in both channels. Compared to the conventional unidirectional BOTDA system of the same sensing range, the proposed BD-BOTDA scheme enables distributed sensing with a performance level comparable to the conventional one with half of the sensing range and a spatial resolution of 2 m, while maintaining the Brillouin signal-to-noise ratio (SNR) and the BFS uncertainty. Based on this technique, we have achieved distributed temperature sensing with a measurement range of 81.9 km fiber at a spatial resolution of 2 m and BFS uncertainty of ~0.44 MHz without introducing any complicated components or schemes. PMID:27999250

  19. Long-Range Cortical Dynamics: A Perspective from the Mouse Sensorimotor Whisker System.

    PubMed

    Ni, Jianguang; Chen, Jerry L

    2017-09-16

    In the mammalian neocortex, the capacity to dynamically route and coordinate the exchange of information between areas is a critical feature of cognitive function, enabling processes such as higher-level sensory processing and sensorimotor integration. Despite the importance attributed to long-range connections between cortical areas, their exact operations and role in cortical function remain an open question. In recent years, progress has been made in understanding long-range cortical circuits through work focused on the mouse sensorimotor whisker system. In this review, we examine recent studies dissecting long-range circuits involved in whisker sensorimotor processing as an entry point for understanding the rules that govern long-range cortical circuit function. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  20. Bound on range precision for shot-noise limited ladar systems.

    PubMed

    Johnson, Steven; Cain, Stephen

    2008-10-01

    The precision of ladar range measurements is limited by noise. The fundamental source of noise in a laser signal is the random time between photon arrivals. This phenomenon, called shot noise, is modeled as a Poisson random process. Other noise sources in the system are also modeled as Poisson processes. Under the Poisson-noise assumption, the Cramer-Rao lower bound (CRLB) on range measurements is derived. This bound on the variance of any unbiased range estimate is greater than the CRLB derived by assuming Gaussian noise of equal variance. Finally, it is shown that, for a ladar capable of dividing a fixed amount of energy into multiple laser pulses, the range precision is maximized when all energy is transmitted in a single pulse.

  1. Pilot system on extreme climate monitoring and early warning for long range forecast in Korea

    NASA Astrophysics Data System (ADS)

    Cho, K.; Park, B. K.; E-hyung, P.; Gong, Y.; Kim, H. K.; Park, S.; Min, S. K.; Yoo, H. D.

    2015-12-01

    Recently, extreme weather/climate events such as heat waves, flooding/droughts etc. have been increasing in frequency and intensity under climate change over the world. Also, they can have substantial impacts on ecosystem and human society (agriculture, health, and economy) of the affected regions. According to future projections of climate, extreme weather and climate events in Korea are expected to occure more frequently with stronger intensity over the 21st century. For the better long range forecast, it is also fundamentally ruquired to develop a supporting system in terms of extreme weather and climate events including forequency and trend. In this context, the KMA (Korea Meteorological Administration) has recently initiated a development of the extreme climate monintoring and early warning system for long range forecast, which consists of three sub-system components; (1) Real-time climate monitoring system, (2) Ensemble prediction system, and (3) Mechanism analysis and display system for climate extremes. As a first step, a pilot system has been designed focusing on temperature extremes such heat waves and cold snaps using daily, monthly and seasonal observations and model prediction output on the global, regional and national levels. In parallel, the skills of the KMA long range prediction system are being evaluated comprehensively for weather and climate extremes, for which varous case studies are conducted to better understand the observed variations of extrem climates and responsible mechanisms and also to assess predictability of the ensemble prediction system for extremes. Details in the KMA extreme climate monitoring and early warning system will be intorduced and some preliminary results will be discussed for heat/cold waves in Korea.

  2. NASA ground-based and space-based laser ranging systems

    NASA Technical Reports Server (NTRS)

    Fitzmaurice, M. W.

    1978-01-01

    Laser ranging is expected to help unlock the mysteries of the earthquake phenomenon by producing unique results of crustal motions of the Earth. The current state of the art and future projections are presented, including principal applications and characteristics of typical systems.

  3. Long Range Correlations and Phase Transitions in Non-equilibrium Diffusive Systems

    NASA Astrophysics Data System (ADS)

    Bodineau, T.; Derrida, B.; Lecomte, V.; van Wijland, F.

    2008-12-01

    We obtain explicit expressions for the long range correlations in the ABC model and in diffusive models conditioned to produce an atypical current of particles. In both cases, the two-point correlation functions allow one to detect the occurrence of a phase transition as they become singular when the system approaches the transition.

  4. Fractal landscapes in biological systems: long-range correlations in DNA and interbeat heart intervals

    NASA Technical Reports Server (NTRS)

    Stanley, H. E.; Buldyrev, S. V.; Goldberger, A. L.; Hausdorff, J. M.; Havlin, S.; Mietus, J.; Sciortino, F.; Simons, M.

    1992-01-01

    Here we discuss recent advances in applying ideas of fractals and disordered systems to two topics of biological interest, both topics having common the appearance of scale-free phenomena, i.e., correlations that have no characteristic length scale, typically exhibited by physical systems near a critical point and dynamical systems far from equilibrium. (i) DNA nucleotide sequences have traditionally been analyzed using models which incorporate the possibility of short-range nucleotide correlations. We found, instead, a remarkably long-range power law correlation. We found such long-range correlations in intron-containing genes and in non-transcribed regulatory DNA sequences as well as intragenomic DNA, but not in cDNA sequences or intron-less genes. We also found that the myosin heavy chain family gene evolution increases the fractal complexity of the DNA landscapes, consistent with the intron-late hypothesis of gene evolution. (ii) The healthy heartbeat is traditionally thought to be regulated according to the classical principle of homeostasis, whereby physiologic systems operate to reduce variability and achieve an equilibrium-like state. We found, however, that under normal conditions, beat-to-beat fluctuations in heart rate display long-range power law correlations.

  5. Fractal landscapes in biological systems: Long-range correlations in DNA and interbeat heart intervals

    NASA Astrophysics Data System (ADS)

    Stanley, H. E.; Buldyrev, S. V.; Goldberger, A. L.; Hausdorff, J. M.; Havlin, S.; Mietus, J.; Peng, C.-K.; Sciortino, F.; Simons, M.

    1992-12-01

    Here we discuss recent advances in applying ideas of fractals and disordered systems to two topics of biological interest, both topics having in common the appearance of scale-free phenomena, i.e., correlations that have no characteristic length scale, typically exhibited by physical systems near a critical point and dynamical systems far from equilibrium. (i) DNA nucleotide sequences have traditionally been analyzed using models which incorporate the possibility of short-range nucleotide correlations. We found, instead, a remarkably long-range power law correlation. We found such long-range correlations in intron-containing genes and in non-transcribed regulatory DNA sequences as well as intragenomic DNA, but not in cDNA sequences or intron-less genes. We also found that the myosin heavy chain family gene evolution increases the fractal complexity of the DNA landscapes, consistent with the intron-late hypothesis of gene evolution. (ii) The healthy heartbeat is traditionally thought to be regulated according to the classical principle of homeostasis. whereby physiologic systems operate to reduce variability and achieve an equilibrium-like state. We found, however, that under normal conditions, beat-to-beat fluctuations in heart rate display long-range power law correlations.

  6. A comparison of laser-based ranging systems for AR/C

    NASA Technical Reports Server (NTRS)

    Katzberg, Stephen J.; Goode, Pleasant W., IV

    1991-01-01

    The three most common types of laser target ranging (time-of-flight, tone modulated, and FM-CW) are discussed in terms of principle of operation. The first, time-of-flight, is shown to depend more on the ability of support electronics than the fundamentals of the concept. Examples in the literature are cited to show the remarkably good performance of time-of-flight systems. A system developed in Finland was shown to have an incremental ranging capability of a few millimeters. The system is not only robust; it does not include additions such as reference legs and the like, which are expected, for improvement in performance. Though not immediately obvious, the second technique, tone modulated ranging is somewhat of an extension of the time-of-flight technique. Finally, the FM-CW technique is presented. This is completely different from the tone or time-of-flight techniques, but is a direct translation of the same-named technique used in radar ranging systems.

  7. Overview of the NASA Wallops Flight Facility Mobile Range Control System

    NASA Technical Reports Server (NTRS)

    Davis, Rodney A.; Semancik, Susan K.; Smith, Donna C.; Stancil, Robert K.

    1999-01-01

    The NASA GSFC's Wallops Flight Facility (WFF) Mobile Range Control System (MRCS) is based on the functionality of the WFF Range Control Center at Wallops Island, Virginia. The MRCS provides real time instantaneous impact predictions, real time flight performance data, and other critical information needed by mission and range safety personnel in support of range operations at remote launch sites. The MRCS integrates a PC telemetry processing system (TELPro), a PC radar processing system (PCDQS), multiple Silicon Graphics display workstations (IRIS), and communication links within a mobile van for worldwide support of orbital, suborbital, and aircraft missions. This paper describes the MRCS configuration; the TELPro's capability to provide single/dual telemetry tracking and vehicle state data processing; the PCDQS' capability to provide real time positional data and instantaneous impact prediction for up to 8 data sources; and the IRIS' user interface for setup/display options. With portability, PC-based data processing, high resolution graphics, and flexible multiple source support, the MRCS system is proving to be responsive to the ever-changing needs of a variety of increasingly complex missions.

  8. Neotectonics of the San Andreas Fault system, basin and range province juncture

    NASA Technical Reports Server (NTRS)

    Estes, J. E.; Crowell, J. C.

    1982-01-01

    The development, active processes, and tectonic interplay of the southern San Andreas fault system and the basin and range province were studied. The study consist of data acquisition and evaluation, technique development, and image interpretation and mapping. Potentially significant geologic findings are discussed.

  9. Development of wide dynamic range beam loss monitor system for J-PARC main ring

    NASA Astrophysics Data System (ADS)

    Satou, K.; Toyama, T.; Kamikubota, N.; Yamada, S.; Yoshida, S.

    2017-07-01

    The new beam loss monitor (BLM) system now in operation at the main ring of J- PARC consists of an isolated front-end current to voltage converter, a VME-based 24 bit ADC system. A dual detector system employs a proportional-type gas chamber (PBLM) and an air- filled ionization chamber (AIC). The system shows a wide dynamic range of 160 dB. It can detect the low level signal that would arise in the case of the detection of residual dose in the ring itself after the beam has been turned off as well as an event such as high level beam loss at the collimators. The signal rise time of the waveform obtained is 17 µs which is fast enough to meet the speed requirement of the Machine Protection System (MPS); which is that the MPS should dump the beam within 100 µs when the beam loss signal exceeds the reference levels set in the ADC system.

  10. Field testing and applications of the Ultrasonic Ranging and Data (USRAD) System

    SciTech Connect

    Dickerson, K.S.; Pickering, D.A.; Blair, M.S.; Espegren, M.L.; Nyquist, J.E.

    1989-01-01

    The Ultrasonic Ranging and Data (USRAD) System is a patented, computerized data acquisition system developed to relate the radiological surveyor's precise physical location to instantaneous radiation data taken during walk-on surveys. The USRAD System incorporates three technologies: radio frequency communications, ultrasonics, and microcomputers. Initial field testing of the USRAD System has resulted in several improvements to walk-on radiological surveys including real-time position data, reproducible survey results, on-site verification of survey coverage, on-site data reduction and graphics, and permanent data storage on magnetic media. Although the USRAD System was developed specifically for use with a gamma-ray detector, it is adaptable to other instruments. Applications of the USRAD System may include verification of remediated and uncontaminated areas, emergency response in mapping pollutant locations after accidents, and characterization of hazardous waste areas. 2 refs., 8 figs.

  11. Long-range corrected hybrid functionals for π-conjugated systems: Dependence of the range-separation parameter on conjugation length

    NASA Astrophysics Data System (ADS)

    Körzdörfer, Thomas; Sears, John S.; Sutton, Christopher; Brédas, Jean-Luc

    2011-11-01

    Long-range corrected (range-separated hybrid) functionals represent a relatively new class of functionals for generalized Kohn-Sham theory that have proven to be very successful, for instance, when it comes to predicting ionization potentials and energy gaps for a wide range of molecules and solids. The results obtained from long-range corrected density functional theory approaches can be improved dramatically, if the range-separation parameter (ω) is optimized for each system separately. In this work, we have optimized ω for a series of π-conjugated molecular systems of increasing length by forcing the resulting functionals to obey the ionization potential-theorem, i.e., that their highest occupied eigenvalue be equal to the ΔSCF ionization potential. The optimized ω values are observed to vary substantially from their default values for the functionals. For highly conjugated chains such as oligoacenes and polyenes, we find that the characteristic length scale of the range-separation, i.e., 1/ω, grows almost linearly with the number of repeat units, for saturated alkane chains, however, 1/ω quickly saturates after 5-6 repeat units. For oligothiophenes, we find that 1/ω grows linearly for the shorter oligomers but then saturates at around 10 repeat units. Our results point to a close relation between the optimal range-separation parameter and the degree of conjugation in the system.

  12. Development of measurement system for task oriented step tracking using laser range finder.

    PubMed

    Matsumura, Tetsuya; Moriguchi, Toshiki; Yamada, Minoru; Uemura, Kazuki; Nishiguchi, Shu; Aoyama, Tomoki; Takahashi, Masaki

    2013-05-22

    Avoiding a fall requires fast and appropriate step responses, stepping speed as a fall risk indicator has only been assessed in older adults. We have developed a new measurement system that applies a laser range finder to assess temporal and spatial parameters of stepping performance such as step speed, length, and accuracy. This measurement system has higher portability, lower cost, and can analyze a larger number of temporal and spatial parameters than existing measurement systems. The aim of this study was to quantify the system for measuring reaction time and stride duration by compared to that obtained using a force platform. Ten healthy young adults performed steps in response to visual cues. The measurement system applied a laser range finder to measure the position and velocity of the center of each leg and of both legs.We applied the developed measurement system to the rhythmic stepping exercise and measured reaction time and stride duration. In addition, the foot-off time and foot-contact time were quantified using the measurement system, and compared to the foot-off time and foot-contact time quantified using a force platform. We confirmed that the measurement system can detect where a participant stood and measured reaction time and stride duration.Remarkable consistency was observed in the test-retest reliability of the foot-off time and foot-contact time quantified by the measurement system (p < 0.001). The foot-off time and foot-contact time quantified by the measurement system were highly correlated with the foot-off time and foot-contact time quantified by the force platform (reaction time: r = 0.997, stride duration: r = 0.879; p < 0.001). The new measurement system provided a valid measure of temporal step parameters in young healthy adults.The validity of the system to measure reaction time and stride duration was evaluated, and confirmed by applying to the rhythmic stepping exercise.

  13. Development of a precision, wide-dynamic-range actuator for use in active optical systems

    NASA Technical Reports Server (NTRS)

    Lorell, K. R.; Aubrun, J-N.; Zacharie, D. F.; Perez, E. O.

    1989-01-01

    The design, operation, and performance of a wide-dynamic-range optical-quality actuator are discussed. The actuator uses a closed-loop control system to maintain accurate positioning and has an rms noise performance of 20 nm. A unique force offloading mechanism allows the actuator coil to dissipate less than 3 mW under quiescent conditions. The operation of an experimental segmented optical system that uses 18 of the actuators is examined to show how they are integrated into an actual system.

  14. Application of the NAVSTAR/Global Positioning System on Instrumented Ranges

    DTIC Science & Technology

    1981-03-01

    LEVEL NAVAL POSTGRADUATE SCHOOL Monterey, California ý’N,,C 1t, L0 THES IS APPLICA±’ION OF THE NAVSTAR/GLOBAL POSITIONING SYSTEM ON INSTRUMENTED ...ViUMOIRN 4. TITLE (and Subtitle) &.TyPIE OF fE T1991 0 PICRIVO COVERED Application of the NAVSTAR/GLOBAL 4’atch13 Positioning System On Instrumented ...8217" the results of a five day demonstration conducted on an instrumented range using a Global Positioning System prototype receiver are given. It is con

  15. The Ansel Adams zone system: HDR capture and range compression by chemical processing

    NASA Astrophysics Data System (ADS)

    McCann, John J.

    2010-02-01

    We tend to think of digital imaging and the tools of PhotoshopTM as a new phenomenon in imaging. We are also familiar with multiple-exposure HDR techniques intended to capture a wider range of scene information, than conventional film photography. We know about tone-scale adjustments to make better pictures. We tend to think of everyday, consumer, silver-halide photography as a fixed window of scene capture with a limited, standard range of response. This description of photography is certainly true, between 1950 and 2000, for instant films and negatives processed at the drugstore. These systems had fixed dynamic range and fixed tone-scale response to light. All pixels in the film have the same response to light, so the same light exposure from different pixels was rendered as the same film density. Ansel Adams, along with Fred Archer, formulated the Zone System, staring in 1940. It was earlier than the trillions of consumer photos in the second half of the 20th century, yet it was much more sophisticated than today's digital techniques. This talk will describe the chemical mechanisms of the zone system in the parlance of digital image processing. It will describe the Zone System's chemical techniques for image synthesis. It also discusses dodging and burning techniques to fit the HDR scene into the LDR print. Although current HDR imaging shares some of the Zone System's achievements, it usually does not achieve all of them.

  16. Verifying performance characteristics of quantitative analytical systems: calibration verification, linearity, and analytical measurement range.

    PubMed

    Killeen, Anthony A; Long, Tom; Souers, Rhona; Styer, Patricia; Ventura, Christina B; Klee, George G

    2014-09-01

    Both the regulations in the Clinical Laboratory Improvement Amendments of 1988 (CLIA) and the checklists of the College of American Pathologists (CAP) Laboratory Accreditation Program require clinical laboratories to verify performance characteristics of quantitative test systems. Laboratories must verify performance claims when introducing an unmodified, US Food and Drug Administration-cleared or approved test system, and they must comply with requirements for periodic calibration and calibration verification for existing test systems. They must also periodically verify the analytical measurement range of many quantitative test systems. To provide definitions for many of the terms used in these regulations, to describe a set of basic analyses that laboratories may adapt to demonstrate compliance with both CLIA and the CAP Laboratory Accreditation Program checklists for performing calibration verification and for verifying the analytical measurement range of test systems, to review some of the recommended procedures for establishing performance goals, and to provide data illustrating the performance goals used in some of the CAP's calibration verification and linearity surveys. The CAP's calibration verification and linearity survey programs, the CLIA regulations, the Laboratory Accreditation Program requirements, and published literature were used to meet these objectives. Calibration verification and linearity and analytical measurement range verification should be performed using suitable materials with assessment of results using well-defined evaluation protocols. We describe the CAP's calibration verification and linearity programs that may be used for these purposes.

  17. Validity of the no-pumping theorem in systems with finite-range interactions between particles

    NASA Astrophysics Data System (ADS)

    Rahav, Saar

    2017-01-01

    The no-pumping theorem states that seemingly natural driving cycles of stochastic machines fail to generate directed motion. Initially derived for single particle systems, the no-pumping theorem was recently extended to many-particle systems with zero-range interactions. Interestingly, it is known that the theorem is violated by systems with exclusion interactions. These two paradigmatic interactions differ by two qualitative aspects: the range of interactions and the dependence of branching fractions on the state of the system. In this work two different models are studied in order to identify the qualitative property of the interaction that leads to breakdown of no pumping. A model with finite-range interaction is shown analytically to satisfy no pumping. In contrast, a model in which the interaction affects the probabilities of reaching different sites, given that a particle is making a transition, is shown numerically to violate the no-pumping theorem. The results suggest that systems with interactions that lead to state-dependent branching fractions do not satisfy the no-pumping theorem.

  18. Development of an Interferometric Laser Ranging System for a Follow-On Gravity Mission to GRACE

    NASA Astrophysics Data System (ADS)

    Nerem, R. S.; Bender, P.; Loomis, B.; Watkins, M. M.; Folkner, W. M.; Stephens, M.; Craig, R.; Leitch, J.; Pierce, R.

    2006-12-01

    The Gravity Recovery and Climate Experiment (GRACE) has ushered in a new era for satellite measurements of the Earth system. The tremendous advances made by GRACE have led to an interest in launching a follow- on mission with even better spatial resolution. The spatial resolution can be improved by improving the ranging performance, implementing a drag-free control system, and flying at a lower altitude. This presentation will focus on an effort, funded by NASA's Instrument Incubator Program, to develop an interferometric laser ranging system that we expect to perform near the 1 nm/sec level or better over 5 second intervals, which when coupled with other mission improvements, would improve the spatial resolution to ~100 km for 1 cm water equivalent accuracy. We have built an engineering model of the instrument, and will report results from testing this instrument in the laboratory. The laser system will range directly to the proof mass of the drag-free system, eliminating many of the difficulties associated with post-processing the accelerometer data on GRACE. Using the expected instrument performance, we will also summarize the gravity recovery accuracies expected if the instrument were flown.

  19. Development of a fast proton range radiography system for quality assurance in hadrontherapy

    NASA Astrophysics Data System (ADS)

    Bucciantonio, M.; Amaldi, U.; Kieffer, R.; Sauli, F.; Watts, D.

    2013-12-01

    We describe the development of a Proton Range Radiography system with an imaging area of 30×30 cm2 for two dimensional mapping of the integrated density in a target. Proton transmission radiographic images are produced by measuring, with a pair of position-sensitive detectors (GEM chambers), the direction of the protons transmitted through the patient and, with a stack of scintillators, the residual range of the protons leaving the patient. To match the data rate requirements of an in-beam diagnostic, a novel data acquisition system for the tracking detectors has been designed to operate at 1 MHz data flow. Laboratory tests exposing the GEM detector with high flux X-rays confirm the fast response of the new data acquisition system. Images of several phantoms have been recorded to demonstrate the GEM position accuracy.

  20. Geothermal Resource Analysis and Structure of Basin and Range Systems, Especially Dixie Valley Geothermal Field, Nevada

    SciTech Connect

    David Blackwell; Kenneth Wisian; Maria Richards; Mark Leidig; Richard Smith; Jason McKenna

    2003-08-14

    Publish new thermal and drill data from the Dizie Valley Geothermal Field that affect evaluation of Basin and Range Geothermal Resources in a very major and positive way. Completed new geophysical surveys of Dizie Valley including gravity and aeromagnetics and integrated the geophysical, seismic, geological and drilling data at Dizie Valley into local and regional geologic models. Developed natural state mass and energy transport fluid flow models of generic Basin and Range systems based on Dizie Valley data that help to understand the nature of large scale constraints on the location and characteristics of the geothermal systems. Documented a relation between natural heat loss for geothermal and electrical power production potential and determined heat flow for 27 different geothermal systems. Prepared data set for generation of a new geothermal map of North American including industry data totaling over 25,000 points in the US alone.

  1. Extreme Quantum Advantage when Simulating Classical Systems with Long-Range Interaction.

    PubMed

    Aghamohammadi, Cina; Mahoney, John R; Crutchfield, James P

    2017-07-27

    Classical stochastic processes can be generated by quantum simulators instead of the more standard classical ones, such as hidden Markov models. One reason for using quantum simulators has recently come to the fore: they generally require less memory than their classical counterparts. Here, we examine this quantum advantage for strongly coupled spin systems-in particular, the Dyson one-dimensional Ising spin chain with variable interaction length. We find that the advantage scales with both interaction range and temperature, growing without bound as interaction range increases. In particular, simulating Dyson's original spin chain with the most memory-efficient classical algorithm known requires infinite memory, while a quantum simulator requires only finite memory. Thus, quantum systems can very efficiently simulate strongly coupled one-dimensional classical spin systems.

  2. Scaling laws for the largest Lyapunov exponent in long-range systems: A random matrix approach.

    PubMed

    Anteneodo, Celia; Vallejos, Raúl O

    2002-01-01

    We investigate the laws that rule the behavior of the largest Lyapunov exponent (LLE) in many particle systems with long-range interactions. We consider as a representative system the so-called Hamiltonian alpha-XY model where the adjustable parameter alpha controls the range of the interactions of N ferromagnetic spins in a lattice of dimension d. In previous work the dependence of the LLE with the system size N, for sufficiently high energies, was established through numerical simulations. In the thermodynamic limit, the LLE becomes constant for alpha>d whereas it decays as an inverse power law of N for alpha

  3. Passive signatures concealed objects recorded by multispectral and hyperspectral systems in visible, infrared and terahertz range

    NASA Astrophysics Data System (ADS)

    Kastek, Mariusz; Kowalski, Marcin; Polakowski, Henryk; Lagueux, Philippe; Gagnon, Marc-André

    2014-06-01

    Risks to the safety of public zones (generally available for people) are related mainly to the presence of hidden dangerous objects (such as knives, guns, bombs etc.) and their usage. Modern system for the monitoring of such zones attempt to detect dangerous tools using multispectral cameras working in different spectral ranges: the visible radiation, near, medium and long range infrared and recently also in terahertz range. In order to develop methods and algorithms to detect hidden objects it is necessary to determine the thermal signatures of such objects of interest. The laboratory measurements were conducted to determine the thermal signatures of dangerous tools hidden under various clothes in different ambient conditions. Cameras used for measurements were working in spectral range 0.6-12.5 µm. An infrared imaging Fourier transform spectroradiometer was also used, working in spectral range 7.7-11.7 µm. Analysis of registered thermograms and hyperspectral datacubes has yielded the thermal signatures for: two types of guns, two types of knives and home-made explosive bombs. The determined thermal signatures will be used in the development of method and algorithms of image analysis implemented in proposed monitoring systems.

  4. Effects of Triclosan on Neural Stem Cell Viability and Survival

    PubMed Central

    Park, Bo Kyung; Gonzales, Edson Luck T.; Yang, Sung Min; Bang, Minji; Choi, Chang Soon; Shin, Chan Young

    2016-01-01

    Triclosan is an antimicrobial or sanitizing agent used in personal care and household products such as toothpaste, soaps, mouthwashes and kitchen utensils. There are increasing evidence of the potentially harmful effects of triclosan in many systemic and cellular processes of the body. In this study, we investigated the effects of triclosan in the survivability of cultured rat neural stem cells (NSCs). Cortical cells from embryonic day 14 rat embryos were isolated and cultured in vitro. After stabilizing the culture, triclosan was introduced to the cells with concentrations ranging from 1 μM to 50 μM and in varied time periods. Thereafter, cell viability parameters were measured using MTT assay and PI staining. TCS decreased the cell viability of treated NSC in a concentration-dependent manner along with increased expressions of apoptotic markers, cleaved caspase-3 and Bax, while reduced expression of Bcl2. To explore the mechanisms underlying the effects of TCS in NSC, we measured the activation of MAPKs and intracellular ROS. TCS at 50 μM induced the activations of both p38 and JNK, which may adversely affect cell survival. In contrast, the activities of ERK, Akt and PI3K, which are positively correlated with cell survival, were inhibited. Moreover, TCS at this concentration augmented the ROS generation in treated NSC and depleted the glutathione activity. Taken together, these results suggest that TCS can induce neurodegenerative effects in developing rat brains through mechanisms involving ROS activation and apoptosis initiation. PMID:26759708

  5. Effects of Triclosan on Neural Stem Cell Viability and Survival.

    PubMed

    Park, Bo Kyung; Gonzales, Edson Luck T; Yang, Sung Min; Bang, Minji; Choi, Chang Soon; Shin, Chan Young

    2016-01-01

    Triclosan is an antimicrobial or sanitizing agent used in personal care and household products such as toothpaste, soaps, mouthwashes and kitchen utensils. There are increasing evidence of the potentially harmful effects of triclosan in many systemic and cellular processes of the body. In this study, we investigated the effects of triclosan in the survivability of cultured rat neural stem cells (NSCs). Cortical cells from embryonic day 14 rat embryos were isolated and cultured in vitro. After stabilizing the culture, triclosan was introduced to the cells with concentrations ranging from 1 μM to 50 μM and in varied time periods. Thereafter, cell viability parameters were measured using MTT assay and PI staining. TCS decreased the cell viability of treated NSC in a concentration-dependent manner along with increased expressions of apoptotic markers, cleaved caspase-3 and Bax, while reduced expression of Bcl2. To explore the mechanisms underlying the effects of TCS in NSC, we measured the activation of MAPKs and intracellular ROS. TCS at 50 μM induced the activations of both p38 and JNK, which may adversely affect cell survival. In contrast, the activities of ERK, Akt and PI3K, which are positively correlated with cell survival, were inhibited. Moreover, TCS at this concentration augmented the ROS generation in treated NSC and depleted the glutathione activity. Taken together, these results suggest that TCS can induce neurodegenerative effects in developing rat brains through mechanisms involving ROS activation and apoptosis initiation.

  6. Long-range correlations in self-gravitating N-body systems

    NASA Astrophysics Data System (ADS)

    Huber, D.; Pfenniger, D.

    2002-04-01

    Observed self-gravitating systems reveal often fragmented, non-equilibrium structures that feature characteristic long-range correlations. However, models accounting for non-linear structure growth are not always consistent with observations and a better understanding of self-gravitating N-body systems appears necessary. Because unstable gravitating systems are sensitive to non-gravitational perturbations, we study the effect of different dissipative factors as well as different small and large scale boundary conditions on idealized N-body systems. We find, in the interval of negative specific heat, equilibrium properties differing from theoretical predictions made for gravo-thermal systems, substantiating the importance of microscopic physics and the lack of consistent theoretical tools to describe self-gravitating gas. Also, in the interval of negative specific heat, yet outside of equilibrium, unforced systems fragment and establish transient long-range correlations. The strength of these correlations depends on the degree of granularity, which shows that the mass and force resolution should be coherent. Finally, persistent correlations appear in model systems subject to an energy flow.

  7. Advanced technologies in the ASI MLRO towards a new generation laser ranging system

    NASA Technical Reports Server (NTRS)

    Varghese, Thomas; Bianco, Giuseppe

    1994-01-01

    Matera Laser Ranging Observatory (MLRO) is a high performance, highly automated optical and astronomical observatory currently under design and development by AlliedSignal for the Italian Space Agency (ASI). It is projected to become operational at the Centro Geodesia Spaziale in Matera, Italy, in 1997. MLRO, based on a 1.5-meter astronomical quality telescope, will perform ranging to spacecraft in earthbound orbits, lunar reflectors, and specially equipped deep space missions. The primary emphasis during design is to incorporate state-of-the-art technologies to produce an intelligent, automated, high accuracy ranging system that will mimic the characteristic features of a fifth generation laser ranging system. The telescope has multiple ports and foci to support future experiments in the areas of laser communications, lidar, astrometry, etc. The key features providing state-of-the-art ranging performance include: a diode-pumped picosecond (50 ps) laser, high speed (3-5 GHz) optoelectronic detection and signal processing, and a high accuracy (6 ps) high resolution (less than 2 ps) time measurement capability. The above combination of technologies is expected to yield millimeter laser ranging precision and accuracy on targets up to 300,000 km, surpassing the best operational instrument performance to date by a factor of five or more. Distributed processing and control using a state-of-the-art computing environment provides the framework for efficient operation, system optimization, and diagnostics. A computationally intelligent environment permits optimal planning, scheduling, tracking, and data processing. It also supports remote access, monitor, and control for joint experiments with other observatories.

  8. Cooperative Shielding in Many-Body Systems with Long-Range Interaction.

    PubMed

    Santos, Lea F; Borgonovi, Fausto; Celardo, Giuseppe Luca

    2016-06-24

    In recent experiments with ion traps, long-range interactions were associated with the exceptionally fast propagation of perturbation, while in some theoretical works they have also been related with the suppression of propagation. Here, we show that such apparently contradictory behavior is caused by a general property of long-range interacting systems, which we name cooperative shielding. It refers to shielded subspaces that emerge as the system size increases and inside of which the evolution is unaffected by long-range interactions for a long time. As a result, the dynamics strongly depends on the initial state: if it belongs to a shielded subspace, the spreading of perturbation satisfies the Lieb-Robinson bound and may even be suppressed, while for initial states with components in various subspaces, the propagation may be quasi-instantaneous. We establish an analogy between the shielding effect and the onset of quantum Zeno subspaces. The derived effective Zeno Hamiltonian successfully describes the short-ranged dynamics inside the subspaces up to a time scale that increases with system size. Cooperative shielding can be tested in current experiments with trapped ions.

  9. A digital wide range neutron flux measuring system for HL-2A

    NASA Astrophysics Data System (ADS)

    Yuan, Chen; Wu, Jun; Yin, Zejie

    2017-08-01

    To achieve wide-range, high-integration, and real-time performance on the neutron flux measurement on the HL-2A tokamak, a digital neutron flux measuring (DNFM) system based on the peripheral component interconnection (PCI) eXtension for Instrumentation express (PXIe) bus was designed. This system comprises a charge-sensitive preamplifier and a field programmable gate array (FPGA)-based main electronics plug-in. The DNFM totally covers source-range and intermediate-range neutron flux measurements, and increases system integration by a large margin through joining the pulse-counting mode and Campbell mode. Meanwhile, the neutron flux estimation method based on pulse piling proportions is able to choose and switch measuring modes in accordance with current flux, and this ensures the accuracy of measurements when the neutron flux changes suddenly. It has been demonstrated by simulated signals that the DNFM enhances the full-scale measuring range up to 1.9 × 108 cm-2 s-1, with relative error below 6.1%. The DNFM has been verified to provide a high temporal sensitivity at 10 ms time intervals on a single fission chamber on HL-2A. Contributed paper, published as part of the Proceedings of the 3rd Domestic Electromagnetic Plasma Diagnostics Workshop, September 2016, Hefei, China.

  10. Evaluating the performance of close-range 3D active vision systems for industrial design applications

    NASA Astrophysics Data System (ADS)

    Beraldin, J.-Angelo; Gaiani, Marco

    2004-12-01

    In recent years, active three-dimensional (3D) active vision systems or range cameras for short have come out of research laboratories to find niche markets in application fields as diverse as industrial design, automotive manufacturing, geomatics, space exploration and cultural heritage to name a few. Many publications address different issues link to 3D sensing and processing but currently these technologies pose a number of challenges to many recent users, i.e., "what are they, how good are they and how do they compare?". The need to understand, test and integrate those range cameras with other technologies, e.g. photogrammetry, CAD, etc. is driven by the quest for optimal resolution, accuracy, speed and cost. Before investing, users want to be certain that a given range camera satisfy their operational requirements. The understanding of the basic theory and best practices associated with those cameras are in fact fundamental to fulfilling the requirements listed above in an optimal way. This paper addresses the evaluation of active 3D range cameras as part of a study to better understand and select one or a number of them to fulfill the needs of industrial design applications. In particular, object material and surface features effect, calibration and performance evaluation are discussed. Results are given for six different range cameras for close range applications.

  11. Evaluating the performance of close-range 3D active vision systems for industrial design applications

    NASA Astrophysics Data System (ADS)

    Beraldin, J.-Angelo; Gaiani, Marco

    2005-01-01

    In recent years, active three-dimensional (3D) active vision systems or range cameras for short have come out of research laboratories to find niche markets in application fields as diverse as industrial design, automotive manufacturing, geomatics, space exploration and cultural heritage to name a few. Many publications address different issues link to 3D sensing and processing but currently these technologies pose a number of challenges to many recent users, i.e., "what are they, how good are they and how do they compare?". The need to understand, test and integrate those range cameras with other technologies, e.g. photogrammetry, CAD, etc. is driven by the quest for optimal resolution, accuracy, speed and cost. Before investing, users want to be certain that a given range camera satisfy their operational requirements. The understanding of the basic theory and best practices associated with those cameras are in fact fundamental to fulfilling the requirements listed above in an optimal way. This paper addresses the evaluation of active 3D range cameras as part of a study to better understand and select one or a number of them to fulfill the needs of industrial design applications. In particular, object material and surface features effect, calibration and performance evaluation are discussed. Results are given for six different range cameras for close range applications.

  12. Spin segregation via dynamically induced long-range interactions in a system of ultracold fermions

    SciTech Connect

    Ebling, Ulrich; Eckardt, Andre; Lewenstein, Maciej

    2011-12-15

    We investigate theoretically the time evolution of a one-dimensional system of spin-1/2 fermions in a harmonic trap after, initially, a spiral spin configuration far from equilibrium is created. We predict a spin segregation building up in time already for weak interaction under realistic experimental conditions. The effect relies on the interplay between exchange interaction and the harmonic trap, and it is found for a wide range of parameters. It can be understood as a consequence of an effective, dynamically induced long-range interaction that is derived by integrating out the rapid oscillatory dynamics in the trap.

  13. Design of laser beam expander in underwater high-repetition-rate range-gated imaging system

    NASA Astrophysics Data System (ADS)

    Zhong, Wei; Zhang, Xiaohui

    2015-10-01

    Active underwater imaging systems, using an artificial light source for underwater target illumination, have preferable practical value in military and civil domain. Back-scattering of water impacts imaging system performance by reducing image contrast, and this is especially bad when the light source is close to the camera. Range-gated technique can effectively rejecting the back-scattering of water and improve the range of underwater target detection, while it can only collect image at certain distance for every laser impulse. High-repetition-rate green laser is a better light source in underwater range-gated imaging system. It has smaller pulse energy, while it can improve the imaging result. In order to illuminate the proper area underwater according to the different distance between the laser source and targets, there must be a magnifying-ratio variable beam expander to adjust the divergent angle of the laser. Challenges associated with magnifying-ratio computation and designing of beam expander are difficult to overcome due to the obvious refraction and forward-scattering of water. An efficiency computing method is presented to obtain the magnifying-ratio of beam expander. The illuminating area of laser beam can be computed according to the refraction index and beam spread function (BSF) which has already considered forward-scattering process. The magnifying-ratio range of beam expander should be 0.925~3.09 in order to obtain about φ1m illuminating area when the distance between laser and target is 10~40m. A magnifying-ratio variable beam expander is designed according to computation. Underwater experiments show that this beam expander plays an effective role on illuminating in underwater high-repetition-rate range-rated Imaging system.

  14. Xanthomonas campestris diffusible factor is 3-hydroxybenzoic acid and is associated with xanthomonadin biosynthesis, cell viability, antioxidant activity, and systemic invasion.

    PubMed

    He, Ya-Wen; Wu, Ji'en; Zhou, Lian; Yang, Fan; He, Yong-Qiang; Jiang, Bo-Le; Bai, Linquan; Xu, Yuquan; Deng, Zixin; Tang, Ji-Liang; Zhang, Lian-Hui

    2011-08-01

    Xanthomonas campestris pv. campestris produces a membrane-bound yellow pigment called xanthomonadin. A diffusible factor (DF) has been reported to regulate xanthomonadin biosynthesis. In this study, DF was purified from bacterial culture supernatants using a combination of solvent extraction, flash chromatography, and high-performance liquid chromatography. Mass spectrometry and nuclear magnetic resonance analyses resolved the DF chemical structure as 3-hydroxybenzoic acid (3-HBA), which was further confirmed by synthetic 3-HBA. Significantly, bioassay and in silico analysis suggest that DF production is widely conserved in a range of bacterial species. Analysis of DF derivatives established the hydroxyl group and its position as the key structural features for the role of DF in xanthomonadin biosynthesis. In addition, we showed that DF is also associated with bacterial survival, H2O2 resistance, and systemic invasion. Furthermore, evidence was also presented that DF and diffusible signaling factor have overlapping functions in modulation of bacterial survival, H2O2 resistance, and virulence. Utilization of different mechanisms to modulate similar virulence traits may provide X. campestris pv. campestris with plasticity in response to various environmental cues.

  15. Long ranged interactions in computer simulations and for quasi-2D systems

    NASA Astrophysics Data System (ADS)

    Mazars, Martial

    2011-03-01

    Taking correctly into account long ranged interactions in molecular simulations of molecular models based on classical atomistic representations are essential to obtain reliable results on model systems and in simulations of biological systems. A lot of numerical methods have been developed to this end; the most important of them are reviewed in this paper. Particular attention is paid to the analytical relations between the methods, this allows comparisons on efficiency and accuracy between them and also to proceed to precise implementations of these techniques. While most of the methods have been developed for Coulomb interactions, we give also some analytical details to apply these methods to screened Coulomb (Yukawa interactions), inverse power law and dipolar interactions. Particular types of systems, the quasi-2D systems, are also considered in this paper. Quasi-2D systems represent a large class of physical systems where the spatial extension in one direction of the space is very small by comparison to the other two. These representations are very useful to describe the properties of interfaces, surfaces, fluids confined in slab geometry, etc. In computer simulations, these systems are studied with partial periodic boundary conditions: periodic boundary conditions are taken in directions where spatial extensions are large and some other boundary conditions are taken in directions with smaller extensions. In this review, we describe also the numerical methods developed to handle long ranged interactions in numerical simulations of quasi-2D systems. The properties of quasi-2D systems depend strongly on interactions between components; more specifically electrostatic and magnetic interactions and interactions with external fields are of particular interest in these systems.

  16. Measurement of peak impact loads differ between accelerometers - Effects of system operating range and sampling rate.

    PubMed

    Ziebart, Christina; Giangregorio, Lora M; Gibbs, Jenna C; Levine, Iris C; Tung, James; Laing, Andrew C

    2017-06-14

    A wide variety of accelerometer systems, with differing sensor characteristics, are used to detect impact loading during physical activities. The study examined the effects of system characteristics on measured peak impact loading during a variety of activities by comparing outputs from three separate accelerometer systems, and by assessing the influence of simulated reductions in operating range and sampling rate. Twelve healthy young adults performed seven tasks (vertical jump, box drop, heel drop, and bilateral single leg and lateral jumps) while simultaneously wearing three tri-axial accelerometers including a criterion standard laboratory-grade unit (Endevco 7267A) and two systems primarily used for activity-monitoring (ActiGraph GT3X+, GCDC X6-2mini). Peak acceleration (gmax) was compared across accelerometers, and errors resulting from down-sampling (from 640 to 100Hz) and range-limiting (to ±6g) the criterion standard output were characterized. The Actigraph activity-monitoring accelerometer underestimated gmax by an average of 30.2%; underestimation by the X6-2mini was not significant. Underestimation error was greater for tasks with greater impact magnitudes. gmax was underestimated when the criterion standard signal was down-sampled (by an average of 11%), range limited (by 11%), and by combined down-sampling and range-limiting (by 18%). These effects explained 89% of the variance in gmax error for the Actigraph system. This study illustrates that both the type and intensity of activity should be considered when selecting an accelerometer for characterizing impact events. In addition, caution may be warranted when comparing impact magnitudes from studies that use different accelerometers, and when comparing accelerometer outputs to osteogenic impact thresholds proposed in literature. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  17. Head movements quadruple the range of speeds encoded by the insect motion vision system in hawkmoths.

    PubMed

    Windsor, Shane P; Taylor, Graham K

    2017-10-11

    Flying insects use compensatory head movements to stabilize gaze. Like other optokinetic responses, these movements can reduce image displacement, motion and misalignment, and simplify the optic flow field. Because gaze is imperfectly stabilized in insects, we hypothesized that compensatory head movements serve to extend the range of velocities of self-motion that the visual system encodes. We tested this by measuring head movements in hawkmoths Hyles lineata responding to full-field visual stimuli of differing oscillation amplitudes, oscillation frequencies and spatial frequencies. We used frequency-domain system identification techniques to characterize the head's roll response, and simulated how this would have affected the output of the motion vision system, modelled as a computational array of Reichardt detectors. The moths' head movements were modulated to allow encoding of both fast and slow self-motion, effectively quadrupling the working range of the visual system for flight control. By using its own output to drive compensatory head movements, the motion vision system thereby works as an adaptive sensor, which will be especially beneficial in nocturnal species with inherently slow vision. Studies of the ecology of motion vision must therefore consider the tuning of motion-sensitive interneurons in the context of the closed-loop systems in which they function. © 2017 The Author(s).

  18. 26 CFR 1.167(l)-4 - Public utility property; election to use asset depreciation range system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... depreciation range system. 1.167(l)-4 Section 1.167(l)-4 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT... Individuals and Corporations § 1.167(l)-4 Public utility property; election to use asset depreciation range system. (a) Application of section 167(l) to certain property subject to asset depreciation range system...

  19. 26 CFR 1.167(l)-4 - Public utility property; election to use asset depreciation range system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... depreciation range system. 1.167(l)-4 Section 1.167(l)-4 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT... Individuals and Corporations § 1.167(l)-4 Public utility property; election to use asset depreciation range system. (a) Application of section 167(l) to certain property subject to asset depreciation range system...

  20. 26 CFR 1.167(l)-4 - Public utility property; election to use asset depreciation range system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... depreciation range system. 1.167(l)-4 Section 1.167(l)-4 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT... Individuals and Corporations § 1.167(l)-4 Public utility property; election to use asset depreciation range system. (a) Application of section 167(l) to certain property subject to asset depreciation range system...

  1. 26 CFR 1.167(l)-4 - Public utility property; election to use asset depreciation range system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... depreciation range system. 1.167(l)-4 Section 1.167(l)-4 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT... Individuals and Corporations § 1.167(l)-4 Public utility property; election to use asset depreciation range system. (a) Application of section 167(l) to certain property subject to asset depreciation range system...

  2. Synthesis and analysis of precise spaceborne laser ranging systems, volume 1. [link analysis

    NASA Technical Reports Server (NTRS)

    Paddon, E. A.

    1977-01-01

    Measurement accuracy goals of 2 cm rms range estimation error and 0.003 cm/sec rms range rate estimation error, with no more than 1 cm (range) static bias error are requirements for laser measurement systems to be used in planned space-based earth physics investigations. Constraints and parameters were defined for links between a high altitude, transmit/receive satellite (HATRS), and one of three targets: a low altitude target satellite, passive (LATS), and active low altitude target, and a ground-based target, as well as with operations with a primary transmit/receive terminal intended to be carried as a shuttle payload, in conjunction with the Spacelab program.

  3. Selecting among competing models of electro-optic, infrared camera system range performance

    USGS Publications Warehouse

    Nichols, Jonathan M.; Hines, James E.; Nichols, James D.

    2013-01-01

    Range performance is often the key requirement around which electro-optical and infrared camera systems are designed. This work presents an objective framework for evaluating competing range performance models. Model selection based on the Akaike’s Information Criterion (AIC) is presented for the type of data collected during a typical human observer and target identification experiment. These methods are then demonstrated on observer responses to both visible and infrared imagery in which one of three maritime targets was placed at various ranges. We compare the performance of a number of different models, including those appearing previously in the literature. We conclude that our model-based approach offers substantial improvements over the traditional approach to inference, including increased precision and the ability to make predictions for some distances other than the specific set for which experimental trials were conducted.

  4. Monostatic and bistatic lidar systems: simulation to improve SNR and attainable range in daytime operations

    NASA Astrophysics Data System (ADS)

    Hassebo, Ahmed; Salas, Balbina; Hassebo, Yasser Y.

    2017-02-01

    Lidar daylight measurements are limited by sky background noise (BGN). Reducing the BGN is essential to improve Lidar signal-to-noise ratio (SNR). We report on an optimization technique to improve SNR in a monostatic/biaxial and bistatic Lidar systems by redesigning the geometrical scheme of Lidar receiver. A series of simulations to calculate the overlap area between both transmitter and receiver field of view (FOV) is conducted to determine optimal receiver aperture shapes, locations, and sizes within different lidar ranges. Techniques to vary receiver aperture shape, position, and size to accommodate backscattering signals over a given range, to maximize Lidar SNR, is introduced. At the same short range, numerical results show a better GF of the bistatic compared to the monostatic/biaxial configurations. A complete comparison between monostatic/biaxial and bistatic configurations, for low altitude measurements between 0.1km and 2km, is discussed.

  5. On the Convergence of Finite Range Expansions in 3-nucleon Systems

    NASA Astrophysics Data System (ADS)

    Shepard, James; McNeil, James

    2008-10-01

    We examine the convergence properties of the Effective Range Expansion based on Effective Theories (ET-ERE) of the 2-nucleon scattering amplitude in 3-nucleon applications in the context of a simple rank-1 separable 2-body potential where the finite range effects can be tracked explicitly. To illustrate the approach in a simple context we consider the bound and scattering properties of the ^3S1 and ^4S3/2 2- and 3-nucleon systems. We find that the poor convergence of the 3-nucleon scattering amplitude using the ET-ERE can be traced to its poor account of finite range effects that soften the momentum dependence of the deuteron propagator in the Faddeev kernel. In contrast, a simple separable potential with dipole form factors works remarkably well and forms the leading term of a systematic controlled approximation expansion.

  6. Continuous Symmetry Breaking in 1D Long-Range Interacting Quantum Systems

    NASA Astrophysics Data System (ADS)

    Maghrebi, Mohammad F.; Gong, Zhe-Xuan; Gorshkov, Alexey V.

    2017-07-01

    Continuous symmetry breaking (CSB) in low-dimensional systems, forbidden by the Mermin-Wagner theorem for short-range interactions, may take place in the presence of slowly decaying long-range interactions. Nevertheless, there is no stringent bound on how slowly interactions should decay to give rise to CSB in 1D quantum systems at zero temperature. Here, we study a long-range interacting spin chain with U (1 ) symmetry and power-law interactions V (r )˜1 /rα. Using a number of analytical and numerical techniques, we find CSB for α smaller than a critical exponent αc(≤3 ) that depends on the microscopic parameters of the model. Furthermore, the transition from the gapless X Y phase to the gapless CSB phase is mediated by the breaking of conformal and Lorentz symmetries due to long-range interactions, and is described by a universality class akin to, but distinct from, the Berezinskii-Kosterlitz-Thouless transition. Signatures of the CSB phase should be accessible in existing trapped-ion experiments.

  7. SIRE (sight-integrated ranging equipment): an eyesafe laser rangefinder for armored vehicle fire control systems

    NASA Astrophysics Data System (ADS)

    Keeter, Howard S.; Gudmundson, Glen A.; Woodall, Milton A., II

    1991-04-01

    The Sight Integrated Ranging Equipment (SIRE) incorporates an eyesafe laser rangefinder into the M-36 periscope used in tactical armored vehicles, such as the Commando Stingray light tank. The SIRE unit provides crucial range data simultaneously to the gunner and fire control computer. This capability greatly reduces 'time-to-fire', improves first-round hit probability, and increases the overall effectiveness of the vehicle under actual and simulated battlefield conditions. The SIRE can provide target range up to 10-km, with an accuracy of 10-meters. The key advantage of the SIRE over similar laser rangefinder systems is that it uses erbium:glass as the active lasing medium. With a nominal output wavelength of 1.54-microns, the SIRE can produce sufficient peak power to penetrate long atmospheric paths (even in the presence of obscurants), while remaining completely eyesafe under all operating conditions. The SIRE is the first eyesafe vehicle-based system to combine this level of accuracy, maximum range capability, and fire control interface. It simultaneously improves the accuracy and confidence of the operator, and eliminates the ocular hazard issues typically encountered with laser rangefinder devices.

  8. Range Technique in Scattering Medium Using a Needle-Fiber Optical Coherence Tomography System

    NASA Astrophysics Data System (ADS)

    Li, Tingyu; Nitta, Kouichi; Matoba, Osamu; Yoshimura, Takeaki

    2006-07-01

    A needle-fiber optical coherence tomography (OCT) system designed for guiding epidural anesthesia to a target is presented. In the preliminary experiment, a desired target in tofu as a strong scattering medium can be monitored over a sufficient range of several millimeters within a short measuring time. The axial resolution is 21 μm. In order to investigate the ranging performance, the relation between background noise levels and focus-scattering properties in a confocal optical system is numerically studied by use of Monte Carlo technique. Numerical results indicate that an appropriate focal length of the lens attached to the fiber should be used to separate the OCT signal from strong noise in strongly scattered medium.

  9. Numerical analysis for finite-range multitype stochastic contact financial market dynamic systems.

    PubMed

    Yang, Ge; Wang, Jun; Fang, Wen

    2015-04-01

    In an attempt to reproduce and study the dynamics of financial markets, a random agent-based financial price model is developed and investigated by the finite-range multitype contact dynamic system, in which the interaction and dispersal of different types of investment attitudes in a stock market are imitated by viruses spreading. With different parameters of birth rates and finite-range, the normalized return series are simulated by Monte Carlo simulation method and numerical studied by power-law distribution analysis and autocorrelation analysis. To better understand the nonlinear dynamics of the return series, a q-order autocorrelation function and a multi-autocorrelation function are also defined in this work. The comparisons of statistical behaviors of return series from the agent-based model and the daily historical market returns of Shanghai Composite Index and Shenzhen Component Index indicate that the proposed model is a reasonable qualitative explanation for the price formation process of stock market systems.

  10. Thermal surveillance of volcanoes of the Cascade Range and Iceland utilizing ERTS DCP systems and imagery

    NASA Technical Reports Server (NTRS)

    Friedman, J. D. (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. Significant results of the thermal surveillance of volcanoes experiment during 1972 included the design, construction, emplacement, and successful operation at volcanic sites in the Cascade Range, North America and on Surtsey, Iceland, of automated thermistor arrays which transmit ground and fumarole temperatures via the ERTS-1 data communication system to Goddard Space Flight Center. Temperature, radiance, and anomalous heat flow variations are being plotted by a U.S. Geological Survey IBM 360/65 computer program to show daily fluctuations at each of the sites. Results are being compiled in conjunction with NASA and USGS aircraft infrared survey data to provide thermal energy yield estimates during the current repose period of several Cascade Range volcanic systems. ERTS-1 MSS images have provided new information on the extent of structural elements controlling thermal emission at Lassen Volcanic National Park.

  11. Numerical analysis for finite-range multitype stochastic contact financial market dynamic systems

    NASA Astrophysics Data System (ADS)

    Yang, Ge; Wang, Jun; Fang, Wen

    2015-04-01

    In an attempt to reproduce and study the dynamics of financial markets, a random agent-based financial price model is developed and investigated by the finite-range multitype contact dynamic system, in which the interaction and dispersal of different types of investment attitudes in a stock market are imitated by viruses spreading. With different parameters of birth rates and finite-range, the normalized return series are simulated by Monte Carlo simulation method and numerical studied by power-law distribution analysis and autocorrelation analysis. To better understand the nonlinear dynamics of the return series, a q-order autocorrelation function and a multi-autocorrelation function are also defined in this work. The comparisons of statistical behaviors of return series from the agent-based model and the daily historical market returns of Shanghai Composite Index and Shenzhen Component Index indicate that the proposed model is a reasonable qualitative explanation for the price formation process of stock market systems.

  12. Analog VLSI Models of Range-Tuned Neurons in the Bat Echolocation System

    NASA Astrophysics Data System (ADS)

    Cheely, Matthew; Horiuchi, Timothy

    2003-12-01

    Bat echolocation is a fascinating topic of research for both neuroscientists and engineers, due to the complex and extremely time-constrained nature of the problem and its potential for application to engineered systems. In the bat's brainstem and midbrain exist neural circuits that are sensitive to the specific difference in time between the outgoing sonar vocalization and the returning echo. While some of the details of the neural mechanisms are known to be species-specific, a basic model of reafference-triggered, postinhibitory rebound timing is reasonably well supported by available data. We have designed low-power, analog VLSI circuits to mimic this mechanism and have demonstrated range-dependent outputs for use in a real-time sonar system. These circuits are being used to implement range-dependent vocalization amplitude, vocalization rate, and closest target isolation.

  13. Numerical analysis for finite-range multitype stochastic contact financial market dynamic systems

    SciTech Connect

    Yang, Ge; Wang, Jun; Fang, Wen

    2015-04-15

    In an attempt to reproduce and study the dynamics of financial markets, a random agent-based financial price model is developed and investigated by the finite-range multitype contact dynamic system, in which the interaction and dispersal of different types of investment attitudes in a stock market are imitated by viruses spreading. With different parameters of birth rates and finite-range, the normalized return series are simulated by Monte Carlo simulation method and numerical studied by power-law distribution analysis and autocorrelation analysis. To better understand the nonlinear dynamics of the return series, a q-order autocorrelation function and a multi-autocorrelation function are also defined in this work. The comparisons of statistical behaviors of return series from the agent-based model and the daily historical market returns of Shanghai Composite Index and Shenzhen Component Index indicate that the proposed model is a reasonable qualitative explanation for the price formation process of stock market systems.

  14. Long-range maintenance planning: A case study of working system

    SciTech Connect

    Flanigan, M.J.

    1991-10-01

    This paper addresses the development of the Lawrence Livermore National Laboratory (LLNL) Maintenance Planning System (MPS). The pitfalls encountered and overcome, and future expansion plans. The MPS provides the ability to develop and track long-range programs, i.e., conversion of chlorofluorocarbon (CFC) equipment to hydrochlorofluorocaron (HCFC), roofing, roads, etc., in addition to providing invaluable information and data for current year budget justification.

  15. Atmospheric refraction effects on baseline error in satellite laser ranging systems

    NASA Technical Reports Server (NTRS)

    Im, K. E.; Gardner, C. S.

    1982-01-01

    Because of the mathematical complexities involved in exact analyses of baseline errors, it is not easy to isolate atmospheric refraction effects; however, by making certain simplifying assumptions about the ranging system geometry, relatively simple expressions can be derived which relate the baseline errors directly to the refraction errors. The results indicate that even in the absence of other errors, the baseline error for intercontinental baselines can be more than an order of magnitude larger than the refraction error.

  16. Kinetic Glass Transition in a Micellar System with Short-Range Attractive Interaction

    SciTech Connect

    Mallamace, F.; Gambadauro, P.; Micali, N.; Chen, S.-H.

    2000-06-05

    We show that percolation and structural arrest transitions coexist in different regions of the phase diagram of a copolymer-micellar system and relate them to short-range intermicellar attraction. The intermediate scattering function shows a nonergodic transition along a temperature and concentration dependent line. Analyses show a logarithmic time dependence, attributed to a higher-order glass transition singularity predicted by mode-coupling theory, followed by a power law. (c) 2000 The American Physical Society.

  17. High density, multi-range analog output Versa Module Europa board for control system applications

    SciTech Connect

    Singh, Kundan; Das, Ajit Lal

    2014-01-15

    A new VMEDAC64, 12-bit 64 channel digital-to-analog converter, a Versa Module Europa (VME) module, features 64 analog voltage outputs with user selectable multiple ranges, has been developed for control system applications at Inter University Accelerator Centre. The FPGA (Field Programmable Gate Array) is the module's core, i.e., it implements the DAC control logic and complexity of VMEbus slave interface logic. The VMEbus slave interface and DAC control logic are completely designed and implemented on a single FPGA chip to achieve high density of 64 channels in a single width VME module and will reduce the module count in the control system applications, and hence will reduce the power consumption and cost of overall system. One of our early design goals was to develop the VME interface such that it can be easily integrated with the peripheral devices and satisfy the timing specifications of VME standard. The modular design of this module reduces the amount of time required to develop other custom modules for control system. The VME slave interface is written as a single component inside FPGA which will be used as a basic building block for any VMEbus interface project. The module offers multiple output voltage ranges depending upon the requirement. The output voltage range can be reduced or expanded by writing range selection bits in the control register. The module has programmable refresh rate and by default hold capacitors in the sample and hold circuit for each channel are charged periodically every 7.040 ms (i.e., update frequency 284 Hz). Each channel has software controlled output switch which disconnects analog output from the field. The modularity in the firmware design on FPGA makes the debugging very easy. On-board DC/DC converters are incorporated for isolated power supply for the analog section of the board.

  18. A low-noise laser-gated imaging system for long-range target identification

    NASA Astrophysics Data System (ADS)

    Baker, Ian M.; Duncan, Stuart S.; Copley, Jeremy W.

    2004-08-01

    BAE SYSTEMS has developed a laser-illuminated, gated imaging system for long range target identification which has generated bright images at ranges in excess of 10km from modest laser energies. The system is based on a short pulsewidth laser and a custom detector for sensing the return pulse. The source is a Nd YAG laser converted by an optical parametric oscillator (OPO) to 1571nm and producing 20ns pulses at 15Hz. The detector (named SWIFT) is a 320x256 array of HgCdTe photodiodes operating with high avalanche gain to achieve sensitivities as low as 10 photon rms. A custom silicon multiplexer performs the signal injection and temporal gating function, and adds additional electronic gain. Trials show that the current detectors have gate edges equivalent to 1.5m in range and complete extinction of signals outside of the gated range. The detector is encapsulated in an integrated-detector-cooler-assembly and utilises standard productionised thermal imaging electronics to perform non-uniformity correction and grey scale images. Imaging trials using the camera have shown little excess noise, crosstalk or non-uniformity due to the use of avalanching in the HgCdTe photodiodes up to gains of over 100. The images have shown high spatial resolution arising from the use of solid state focal plane array technology. The imagery, collected both in the laboratory and in field trials, has been used to explore the phenomenology unique to laser-illuminated targets and to verify system models.

  19. A Dose-Ranging Study of a Methylphenidate Transdermal System in Children with ADHD

    ERIC Educational Resources Information Center

    Pelham, William E.; Manos, Michael J.; Ezzell, Cora E.; Tresco, Katy E.; Gnagy, Elizabeth M.; Hoffman, Martin T.; Onyango, Adia N.; Fabiano, Gregory A.; Lopez-Williams, Andy; Wymbs, Brian T.; Caserta, Donald; Chronis, Andrea M.; Burrows-MacLean, Lisa; Morse, Gene

    2005-01-01

    Objective: This was a multicenter, double-blind, randomized, dose-ranging study of a methylphenidate (MPH) transdermal system (MTS). Medication (placebo, 0.45, 0.9, and 1.8 mg/h) was crossed with application time (6 a.m., 7 a.m.) to evaluate MTS efficacy and influence of exposure time on morning effects. Method: The study took place in a summer…

  20. High density, multi-range analog output Versa Module Europa board for control system applications.

    PubMed

    Singh, Kundan; Das, Ajit Lal

    2014-01-01

    A new VMEDAC64, 12-bit 64 channel digital-to-analog converter, a Versa Module Europa (VME) module, features 64 analog voltage outputs with user selectable multiple ranges, has been developed for control system applications at Inter University Accelerator Centre. The FPGA (Field Programmable Gate Array) is the module's core, i.e., it implements the DAC control logic and complexity of VMEbus slave interface logic. The VMEbus slave interface and DAC control logic are completely designed and implemented on a single FPGA chip to achieve high density of 64 channels in a single width VME module and will reduce the module count in the control system applications, and hence will reduce the power consumption and cost of overall system. One of our early design goals was to develop the VME interface such that it can be easily integrated with the peripheral devices and satisfy the timing specifications of VME standard. The modular design of this module reduces the amount of time required to develop other custom modules for control system. The VME slave interface is written as a single component inside FPGA which will be used as a basic building block for any VMEbus interface project. The module offers multiple output voltage ranges depending upon the requirement. The output voltage range can be reduced or expanded by writing range selection bits in the control register. The module has programmable refresh rate and by default hold capacitors in the sample and hold circuit for each channel are charged periodically every 7.040 ms (i.e., update frequency 284 Hz). Each channel has software controlled output switch which disconnects analog output from the field. The modularity in the firmware design on FPGA makes the debugging very easy. On-board DC/DC converters are incorporated for isolated power supply for the analog section of the board.

  1. Evaluating home range techniques: use of Global Positioning System (GPS) collar data from chacma baboons.

    PubMed

    Pebsworth, Paula A; Morgan, Hanna R; Huffman, Michael A

    2012-10-01

    Global Positioning System (GPS) collars have revolutionized the field of spatial ecology, but to date, few primate studies have used them. We fitted a free-ranging, semi-habituated, juvenile male chacma baboon (Papio hamadryas ursinus) with an automatic self-releasing GPS collar and tracked his movements for 359 days. The collar captured 4254 fixes out of 5719 programmed opportunities, a 74.4 % acquisition rate, suggesting that the collar effectively tracked this baboon in a variety of habitat types. Of the data points captured, 73.7 % were three-dimensional fixes, and of these fixes, 66.9 % were highly accurate, having a dilution of precision of less than four. We calculated home range using three protocols with three estimation methods: minimum convex polygon, fixed kernel-density estimation (KDE), and fixed r local convex hull. Using all data points and the 95 % contour, these methods created home range estimations ranging from 10.8 to 23.1 km(2) for this baboon troop. Our results indicate that the KDE output using all data locations most accurately represented our data set, as it created a continuous home range boundary that excluded unused areas and outlying, potentially exploratory data points while including all seven sleeping sites and a movement corridor. However, home range estimations generated from KDE varied from 15.4 to 18.8 km(2) depending on the smoothing parameter used. Our results demonstrated that the ad hoc smoothing parameter selection technique was a better method for our data set than either the least squares cross-validation or biased cross-validation techniques. Our results demonstrate the need for primatologists to develop a standardized reporting method which documents the tool, screening protocol, and smoothing parameter used in the creation of home range estimations in order to make comparisons that are meaningful.

  2. Report on the lunar ranging at McDonald Observatory. [spark gap configuration and photomultiplier system

    NASA Technical Reports Server (NTRS)

    Silverberg, E. C.

    1977-01-01

    Range measurements to an accuracy of 5 cm were achieved following improvements in the laser oscillator configuration and the photomultiplier system. Modifications to the laser include a redesigned pockel cell mount to eliminate stressing of the cell crystal; an improved electrically triggered spark gap for sharpening the electrical pulse; the use of a brewster plate in the cavity to eliminate pre-pulsing; improved alignment for the oscillator system; and increased cavity lifetime through thin film polarizer technology. Laser calibration data are presented along with the lunar laser operations log for June to October 1977.

  3. Development and testing of a long-range airborne CO2 DIAL chemical detection system

    NASA Astrophysics Data System (ADS)

    Higdon, N. Scott; Senft, Daniel C.; Fox, Marsha J.; Hamilton, Carla M.; Kelly, Brian T.; Dowling, James A.; Pierrottet, Diego F.; Dean, David R.; Richter, Dale A.; Bousek, Ronald R.

    1998-11-01

    The Air Force Research Laboratory has developed and tested an airborne CO2 differential absorption lidar system for the remote detection of chemicals. The Laser Airborne Remote Sensing DIAL system uses topographic backscatter to provide a long-range measurement of the column-content absorption of chemical plumes in the path of the laser beam. A high-power CO2 laser, capable of operation on multiple isotopes, and a Mersenne telescope constitute the major transceiver components. In addition to the laser, telescope, and transceiver optics, several onboard diagnostic instruments were mounted on the flight bench to monitor and optimize the system performance during airborne operation. The flight bench, electronics racks, and data acquisition and experiment control stations were designed to be integrated onto the AFRL C-135E research aircraft, and to utilize the existing pointing and tracking system on the aircraft.

  4. Problem of the sun radiovision system superresolution in 3-mm-wavelength range

    NASA Astrophysics Data System (ADS)

    Terentiev, Evgeni N.; Pirogov, Yuri A.; Gladun, Valeri V.; Rozanov, Boris A.; Pavlov, Aleksey S.; Tarasova, Oksana A.

    1999-07-01

    Wide usage of new approaches in radiovision for the sake of radio astronomical investigation is expected as they can fix image independently of the atmosphere state. New ranges of radiation registration promise to show new processes and phenomena in astronomy. Existing Sun radiovision system doesn't give possibility to resolve the details of the processes on the Sun fine structure. Near zone of the radiotelescope is so big that it doesn't allow to measure Sun radiovision system Point Spread Function (PSF) by the ground based methods. By the other words, it's impossible to estimate minimal point object (PSF) that could be seen on the Sun by ground based methods. The task of radiovision system PSF estimation was solved valuing the Sun's edge in the assumption of PSF circular symmetry. In the paper the possibilities of developed dialog complex of complicated Sun's radio observing system modeling with subsequent antenna pattern distortions compensation by linear and nonlinear methods.

  5. Endoscopic system for automated high dynamic range inspection of moving periodic structures

    NASA Astrophysics Data System (ADS)

    Hahlweg, Cornelius; Rothe, Hendrik

    2015-09-01

    In the current paper an advanced endoscopic system for high resolution and high dynamic range inspection of periodic structures in rotating machines is presented. We address the system architecture, short time illumination, special optical problems, such as excluding the specular reflex, image processing, forward velocity prediction and metrological image processing. There are several special requirements to be met, such as the thermal stability above 100°C, robustness of the image field, illumination in view direction and the separation of metallic surface diffuse scatter. To find a compromise between image resolution and frame rate, an external sensor system was applied for synchronization with the moving target. The system originally was intended for inspection of thermal engines, but turned out to be of a more general use. Beside the theoretical part and dimensioning issues, practical examples and measurement results are included.

  6. Birth, meaningful viability and abortion.

    PubMed

    Jensen, David

    2015-06-01

    What role does birth play in the debate about elective abortion? Does the wrongness of infanticide imply the wrongness of late-term abortion? In this paper, I argue that the same or similar factors that make birth morally significant with regard to abortion make meaningful viability morally significant due to the relatively arbitrary time of birth. I do this by considering the positions of Mary Anne Warren and José Luis Bermúdez who argue that birth is significant enough that the wrongness of infanticide does not imply the wrongness of late-term abortion. On the basis of the relatively arbitrary timing of birth, I argue that meaningful viability is the point at which elective abortion is prima facie morally wrong. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  7. An interactive system for creating object models from range data based on simulated annealing

    SciTech Connect

    Hoff, W.A.; Hood, F.W.; King, R.H.

    1997-05-01

    In hazardous applications such as remediation of buried waste and dismantlement of radioactive facilities, robots are an attractive solution. Sensing to recognize and locate objects is a critical need for robotic operations in unstructured environments. An accurate 3-D model of objects in the scene is necessary for efficient high level control of robots. Drawing upon concepts from supervisory control, the authors have developed an interactive system for creating object models from range data, based on simulated annealing. Site modeling is a task that is typically performed using purely manual or autonomous techniques, each of which has inherent strengths and weaknesses. However, an interactive modeling system combines the advantages of both manual and autonomous methods, to create a system that has high operator productivity as well as high flexibility and robustness. The system is unique in that it can work with very sparse range data, tolerate occlusions, and tolerate cluttered scenes. The authors have performed an informal evaluation with four operators on 16 different scenes, and have shown that the interactive system is superior to either manual or automatic methods in terms of task time and accuracy.

  8. Quantum spin dynamics and entanglement in systems with long-range interactions

    NASA Astrophysics Data System (ADS)

    Rey, Ana M.

    One of the fundamental goals of modern quantum sciences is to learn how to control and manipulate non-equilibrium many-body systems and use them to make powerful and improved quantum devices, materials and technologies. However, out-of-equilibrium systems are complex, typically strongly correlated and entangled, and thus to model them we are in an urgent need of new methodologies. In this talk I will discuss new theoretical methods that we have developed to investigate emergent non-equilibrium phenomena in driven-dissipative spin systems interacting via long-range interactions. I will show we can capture the dynamics of correlations and entanglement in close systems and the interplay between dissipation and entanglement in open quantum systems including spin-boson models. As a specific application I will discuss the use of our methods to model the spin dynamics exhibited by arrays of trapped ions with controllable long-range interactions. I will show that our predictions are consistent with recent experimental measurements. I will also discuss new protocols to diagnostic and characterize entanglement based on well-established NMR protocols This work is supported by NSF, ARO, AFOSR-MURI, and NIST.

  9. Real-time monitoring of icebreaker propeller blades' ice load using underwater laser ranging system

    NASA Astrophysics Data System (ADS)

    Morin, Andre; Arsenault, Michel; Edgecombe, Merv H.; Radloff, Ernst A.

    1999-03-01

    Navigation in arctic waters presents a formidable challenge to the ships' propulsion systems as large ice pieces impinging on their propeller blades may result in stresses exceeding the strength of blade material. Damage to propellers is costly and can also spell disaster if a shop becomes disabled in a remote area. To prevent such situations, design practice must be improved and validated against experimental data. In this paper we present the design of a system that performs ice load measurements. This system is based on conventional triangulation and uses an array of laser beams aimed at the propeller blades to monitor in real time their deformations. As the propeller rotates, each point rage sensor describes an arc of a circle on the blades. Using template-matching techniques, the range values for these series of arcs can be used to infer the actual ice-induced blade deformations. The actual system provides range measurements at a rate of 2 kHz on three different channels. The system accuracy is 0.5 mm at distances in excess of 3 meters.

  10. Polarized Imaging Lidar Using Underwater Range Gating in a Multifunctional Remote Sensing System.

    NASA Astrophysics Data System (ADS)

    Fournier, G.; Trees, C.

    2016-02-01

    This work describes the design of a compact imaging underwater polarized LIDAR system using a new modular laser beam shaping technology, which ensures eye safe operation at significant optical power levels that were previously unattainable in such an eye safe mode. The system is based on an existing battery powered high efficiency compact range-gated system which can be operated from a variety of underwater vehicles including AUV's. A detailed analysis is presented of the procedure required to successfully extract information on the depth distribution of the inherent optical properties along with the shape of the phase function in the near forward direction. The effect of polarization in helping to constrain and improve the retrieval of these fundamental optical properties of the water column is also discussed. The LIDAR mode is shown to be only one of the many functionalities useful to oceanographic research, which can be implemented using the beam shaping technology described above. Beyond the improvement in range and image quality of gated imaging over conventional imaging in turbid waters, the application of gated-structured imaging can be shown to significantly improve range and precision of 3D bottom mapping near the turbid seabed environment. We will show that the spatial precision that is available is sufficient for seabed habitat mapping and litter identification required for an environmental impact evaluation.

  11. Development, Operation, and Future of a Ranging Video System for Space Applications

    NASA Astrophysics Data System (ADS)

    James, G. H.; Studor, G. F.

    2002-01-01

    There are a multitude of uses in space flight for non-contact three-dimensional information. Examples include structural motion of large structures such as the International Space Station (ISS), landing site sensing during final approach of a multitude of planetary bodies including the Earth, robotic and telerobotic vision sensing, rendezvous and docking, or biomedical measurements. To produce a sensor that can meet this myriad of needs, NASA-JSC and Sandia National Laboratories have recently developed a system called the Laser Dynamic Range Imager (LDRI). This system uses diffuse modulated laser illumination coupled with an intensity modulated video receiver to produce video and range images. The resulting data produces displacement time histories at each of 25,000 active pixels from the range as well as the two cross-plane directions. This system flew on STS-97 as part of ISS construction mission 4A. A variety of on-going enhancements of this technology are driving utility of this technology for a large number of in- space and terrestrial applications. This presentation will cover the following: the basic concept; the development of this technology in support of STS-97/ISS-4A; the operational experience from that flight; results from that mission such as measurements to support the resolution of the solar array tensioning anomaly, structural dynamics measurements, and undocking/fly-around data; on-going technology developments; and future applications of the technology.

  12. Local thermodynamics and the generalized Gibbs-Duhem equation in systems with long-range interactions.

    PubMed

    Latella, Ivan; Pérez-Madrid, Agustín

    2013-10-01

    The local thermodynamics of a system with long-range interactions in d dimensions is studied using the mean-field approximation. Long-range interactions are introduced through pair interaction potentials that decay as a power law in the interparticle distance. We compute the local entropy, Helmholtz free energy, and grand potential per particle in the microcanonical, canonical, and grand canonical ensembles, respectively. From the local entropy per particle we obtain the local equation of state of the system by using the condition of local thermodynamic equilibrium. This local equation of state has the form of the ideal gas equation of state, but with the density depending on the potential characterizing long-range interactions. By volume integration of the relation between the different thermodynamic potentials at the local level, we find the corresponding equation satisfied by the potentials at the global level. It is shown that the potential energy enters as a thermodynamic variable that modifies the global thermodynamic potentials. As a result, we find a generalized Gibbs-Duhem equation that relates the potential energy to the temperature, pressure, and chemical potential. For the marginal case where the power of the decaying interaction potential is equal to the dimension of the space, the usual Gibbs-Duhem equation is recovered. As examples of the application of this equation, we consider spatially uniform interaction potentials and the self-gravitating gas. We also point out a close relationship with the thermodynamics of small systems.

  13. A UHF RFID system with on-chip-antenna tag for short range communication

    NASA Astrophysics Data System (ADS)

    Qi, Peng; Chun, Zhang; Xijin, Zhao; Zhihua, Wang

    2015-05-01

    A UHF RF identification system based on the 0.18 μm CMOS process has been developed for short range and harsh size requirement applications, which is composed of a fully integrated tag and a special reader. The whole tag chip with the antenna takes up an area of 0.36 mm2, which is smaller than other reported tags with an on-chip antenna (OCA) using the standard CMOS process. A self-defined protocol is proposed to reduce the power consumption, and minimize the size of the tag. The specialized SOC reader system consists of the RF transceiver, digital baseband, MCU and host interface. Its power consumption is about 500 mW. Measurement results show that the system's reading range is 2 mm with 20 dBm reader output power. With an inductive antenna printed on a paper substrate around the OCA tag, the reading range can be extended from several centimeters to meters, depending on the shape and size of the inductive antenna.

  14. The effects of short-term hypoxia on human mesenchymal stem cell proliferation, viability and p16INK4A mRNA expression: Investigation using a simple hypoxic culture system with a deoxidizing agent

    PubMed Central

    Ito, Akira; Aoyama, Tomoki; Yoshizawa, Makoto; Nagai, Momoko; Tajino, Junichi; Yamaguchi, Shoki; Iijima, Hirotaka; Zhang, Xiangkai; Kuroki, Hiroshi

    2015-01-01

    A hypoxic environment is thought to be important for the maintenance of stemness and suppressing cell senescence, in stem cells. Therefore, a hypoxic condition is induced during cell expansion and/or induction of intended differentiation. However, the induction of these conditions requires a specially equipped hypoxia chamber and expensive gas mixtures, which are expensive and space-consuming. Owing to these restrictions, appropriate hypoxic conditions cannot be provided during cell transportation, which is increasingly required for regenerative medicine. Hence, a simple and economical culture system is required. The purpose of this study was to investigate the effects of short-term hypoxic conditions on human mesenchymal stem cell (MSC) proliferation, viability, and senescence, utilizing the CulturePal system (CulturePal-Zero and CulturePal-Five), a novel and simple hypoxic culture system with a built-in deoxidizing agent. The O2 concentration in the CulturePal-Zero was observed to reduce to <0.1% within 1 h, and to 5% within 24h in the CulturePal-Five system. Cell proliferation under these hypoxic conditions showed a sharp increase at 5% O2 concentration, and no noticeable cell death was observed even at severe hypoxic conditions (<0.1% O2) up to 72h. The p16INK4A (cell senescence marker) mRNA expression was retained under hypoxic conditions up to 72h, but it was up-regulated under normoxic conditions. Interestingly, the p16INK4A expression altered proportionately to the O2 concentration. These results indicated that the short-term hypoxic condition, at an approximate O2 concentration of 5%, would be suitable for promoting cell proliferation and repressing cell senescence, without aggravating the MSC viability. Therefore, the CulturePal systems may be suitable for providing an appropriate hypoxic condition in stem cell research and transportation. PMID:26195892

  15. Occurrence of Leishmania infantum in the central nervous system of naturally infected dogs: Parasite load, viability, co-infections and histological alterations

    PubMed Central

    Oliveira, Valéria da Costa; Boechat, Viviane Cardoso; Mendes Junior, Artur Augusto Velho; Madeira, Maria de Fátima; Ferreira, Luiz Claudio; Figueiredo, Fabiano Borges; Campos, Monique Paiva; de Carvalho Rodrigues, Francisco das Chagas; Carvalhaes de Oliveira, Raquel de Vasconcellos; Amendoeira, Maria Regina Reis

    2017-01-01

    Zoonotic visceral leishmaniasis is caused by the protozoan Leishmania infantum and little is known about the occurrence and pathogenesis of this parasite in the CNS. The aims of this study were to evaluate the occurrence, viability and load of L. infantum in the CNS, and to identify the neurological histological alterations associated with this protozoan and its co-infections in naturally infected dogs. Forty-eight Leishmania-seropositive dogs from which L. infantum was isolated after necropsy were examined. Cerebrospinal fluid (CSF) samples were analyzed by parasitological culture, quantitative real-time PCR (qPCR) and the rapid immunochromatographic Dual Path Platform test. Brain, spinal cord and spleen samples were submitted to parasitological culture, qPCR, and histological techniques. Additionally, anti-Toxoplasma gondii and anti-Ehrlichia canis antibodies in serum and distemper virus antigens in CSF were investigated. None of the dogs showed neurological signs. All dogs tested positive for L. infantum in the CNS. Viable forms of L. infantum were isolated from CSF, brain and spinal cord in 25% of the dogs. Anti-L. infantum antibodies were detected in CSF in 61% of 36 dogs. Inflammatory histological alterations were observed in the CNS of 31% of the animals; of these, 66% were seropositive for E. canis and/or T. gondii. Amastigote forms were associated with granulomatous non-suppurative encephalomyelitis in a dog without evidence of co-infections. The highest frequency of L. infantum DNA was observed in the brain (98%), followed by the spinal cord (96%), spleen (95%), and CSF (50%). The highest L. infantum load in CNS was found in the spinal cord. These results demonstrate that L. infantum can cross the blood-brain barrier, spread through CSF, and cause active infection in the entire CNS of dogs. Additionally, L. infantum can cause inflammation in the CNS that can lead to neurological signs with progression of the disease. PMID:28419136

  16. Occurrence of Leishmania infantum in the central nervous system of naturally infected dogs: Parasite load, viability, co-infections and histological alterations.

    PubMed

    Oliveira, Valéria da Costa; Boechat, Viviane Cardoso; Mendes Junior, Artur Augusto Velho; Madeira, Maria de Fátima; Ferreira, Luiz Claudio; Figueiredo, Fabiano Borges; Campos, Monique Paiva; de Carvalho Rodrigues, Francisco das Chagas; Carvalhaes de Oliveira, Raquel de Vasconcellos; Amendoeira, Maria Regina Reis; Menezes, Rodrigo Caldas

    2017-01-01

    Zoonotic visceral leishmaniasis is caused by the protozoan Leishmania infantum and little is known about the occurrence and pathogenesis of this parasite in the CNS. The aims of this study were to evaluate the occurrence, viability and load of L. infantum in the CNS, and to identify the neurological histological alterations associated with this protozoan and its co-infections in naturally infected dogs. Forty-eight Leishmania-seropositive dogs from which L. infantum was isolated after necropsy were examined. Cerebrospinal fluid (CSF) samples were analyzed by parasitological culture, quantitative real-time PCR (qPCR) and the rapid immunochromatographic Dual Path Platform test. Brain, spinal cord and spleen samples were submitted to parasitological culture, qPCR, and histological techniques. Additionally, anti-Toxoplasma gondii and anti-Ehrlichia canis antibodies in serum and distemper virus antigens in CSF were investigated. None of the dogs showed neurological signs. All dogs tested positive for L. infantum in the CNS. Viable forms of L. infantum were isolated from CSF, brain and spinal cord in 25% of the dogs. Anti-L. infantum antibodies were detected in CSF in 61% of 36 dogs. Inflammatory histological alterations were observed in the CNS of 31% of the animals; of these, 66% were seropositive for E. canis and/or T. gondii. Amastigote forms were associated with granulomatous non-suppurative encephalomyelitis in a dog without evidence of co-infections. The highest frequency of L. infantum DNA was observed in the brain (98%), followed by the spinal cord (96%), spleen (95%), and CSF (50%). The highest L. infantum load in CNS was found in the spinal cord. These results demonstrate that L. infantum can cross the blood-brain barrier, spread through CSF, and cause active infection in the entire CNS of dogs. Additionally, L. infantum can cause inflammation in the CNS that can lead to neurological signs with progression of the disease.

  17. Output power and efficiency of electromagnetic energy harvesting systems with constrained range of motion

    NASA Astrophysics Data System (ADS)

    Hendijanizadeh, M.; Sharkh, S. M.; Elliott, S. J.; Moshrefi-Torbati, M.

    2013-12-01

    In some energy harvesting systems, the maximum displacement of the seismic mass is limited due to the physical constraints of the device. This is especially the case where energy is harvested from a vibration source with large oscillation amplitude (e.g., marine environment). For the design of inertial systems, the maximum permissible displacement of the mass is a limiting condition. In this paper the maximum output power and the corresponding efficiency of linear and rotational electromagnetic energy harvesting systems with a constrained range of motion are investigated. A unified form of output power and efficiency is presented to compare the performance of constrained linear and rotational systems. It is found that rotational energy harvesting systems have a greater capability in transferring energy to the load resistance than linear directly coupled systems, due to the presence of an extra design variable, namely the ball screw lead. Also, in this paper it is shown that for a defined environmental condition and a given proof mass with constrained throw, the amount of power delivered to the electrical load by a rotational system can be higher than the amount delivered by a linear system. The criterion that guarantees this favourable design has been obtained.

  18. Kinetic equations for systems with long-range interactions: a unified description

    NASA Astrophysics Data System (ADS)

    Chavanis, Pierre-Henri

    2010-05-01

    We complete the existing literature on the kinetic theory of systems with long-range interactions. Starting from the BBGKY hierarchy, or using projection operator technics or a quasilinear theory, a general kinetic equation can be derived when collective effects are neglected. This equation (which is not well known) applies to possibly spatially inhomogeneous systems, which is specific to systems with long-range interactions. Interestingly, the structure of this kinetic equation bears a clear physical meaning in terms of generalized Kubo relations. Furthermore, this equation takes a very similar form for stellar systems and two-dimensional point vortices, providing therefore a unified description of the kinetic theory of these systems. If we assume that the system is spatially homogeneous (or axisymmetric for point vortices), this equation can be simplified and reduces to the Landau equation (or its counterpart for point vortices). Our formalism thus offers a simple derivation of Landau-type equations. We also use this general formalism to derive a kinetic equation, written in angle-action variables, describing spatially inhomogeneous systems with long-range interactions. This new derivation solves the shortcomings of our previous derivation (Chavanis 2007 Physica A 377 469). Finally, we consider a test particle approach and derive general expressions for the diffusion and friction (or drift) coefficients of a test particle evolving in a bath of field particles. We make contact with the expressions previously obtained in the literature. As an application of the kinetic theory, we argue that, for one-dimensional systems and two-dimensional point vortices, the relaxation time is shorter for inhomogeneous (or non-axisymmetric) distributions than for homogeneous (or axisymmetric) distributions because there are potentially more resonances. We compare this prediction with existing numerical results. For the HMF model, we argue that the relaxation time scales like N for

  19. Evaluation of the operating range for ground-based infrared imaging tracking system

    NASA Astrophysics Data System (ADS)

    Zhang, Bin; Zhang, Zhen-duo; Zhang, Shu-mei

    2011-08-01

    Ground-based infrared imaging tracking system (GIITS) is of great importance for aerial target warning and guard. The operating range is one of the key performance specifications, which should be calculated, analyzed and studied during the whole GIITS design process. The operating range is mostly influenced by a few factors, including atmospheric attenuation, the performance of GIITS and feature of target and background. This paper firstly makes analysis and summarization on the definite localizations of the traditional operating range equation of the GIITS. The localizations are mainly in two aspects. On one hand, the dispersion of the image and the effect of image dispersion are not considered in the traditional method; on the other, calculate the radiation power received on the detector in order to analysis whether the output signal meets the detection requirements or not, without considering the effect of the background radiation. By improving of the traditional method, a new operating range calculation model of the GIITS was established based on two requirements. One is that the image size of observed target should meet the requirement of the processor signal extraction. The number of the pixel occupied by target image should be more than 9. The other is that the signal noise ratio (SNR) of the GIITS should not be less than 5 to meet the requirements of the target detection probability and spatial frequency. The SNR calculation equation in form of energy is deduced and the radiation characteristic of the observed target and background are analyzed. When evaluate the operating range of the GIITS using the new method, we should successively calculate two operating range values according to two requirements mentioned above and choose the minimum value as the analytic result. In the end, an evaluation of operating range for fighter aircraft is accomplished as an example. The influence factors in every aspect on operating range were explored by the calculated

  20. An Extended-range Hydrometeorological Ensemble Prediction System for Alpine Catchments in Switzerland

    NASA Astrophysics Data System (ADS)

    Monhart, Samuel; Bogner, Konrad; Spirig, Christoph; Bhend, Jonas; Liniger, Mark A.; Zappa, Massimiliano; Schär, Christoph

    2017-04-01

    In recent years meteorological ensemble prediction systems have increasingly be used to feed hydrological models in order to provide probabilistic streamflow forecasts. Such hydrological ensemble prediction systems (HEPS) have been analyzed for different lead times from short-term to seasonal predictions and are used for different applications. Especially at longer lead times both such forecasts exhibit systematic biases which can be removed by applying bias correction techniques to both the meteorological and/or the hydrological output. However, it is still an open question if pre- or post-processing techniques or both should be applied. We will present first results of the analysis of pre- and post-processed extended-range hydrometeorological forecasts. In a first step the performance of bias corrected and downscaled (using quantile mapping) extended-range meteorological forecasts provided by the ECMWF is assessed for approximately 1000 ground observation sites across Europe. Generally, bias corrected meteorological forecasts show positive skill in terms of CRPSS up to three (two) weeks for weekly mean temperature (precipitation) compared to climatological forecasts. For the Alpine region the absolute skill is generally lower but the relative gain in skill resulting from the bias correction is larger. These pre-processed meteorological forecasts of one year of ECMWF extended-range forecasts and corresponding hindcasts are used to feed a hydrological model for a selected catchment in the Alpine area in Switzerland. Furthermore, different post-processing techniques are tested to correct the resulting streamflow forecasts. This will allow to determine the relative effect of pre- and post-processing of extended-range hydrometeorological predictions in Alpine catchments. Future work will include the combination of these corrected streamflow forecasts with electricity price forecasts to optimize the operations and revenues of hydropower systems in the Alps.

  1. The Termination Of The Northwest Basin And Range Into A Northwest Trending Extensional Fault System

    NASA Astrophysics Data System (ADS)

    Trench, D.; Meigs, A.

    2007-12-01

    Extensional provinces terminate along-strike where extension dissipates to zero, at transform faults, or at triple junctions. Termination of the northern Basin and Range province in western North America has long been thought to be controlled by an intracontinental transform fault, the Brothers Fault zone (BFz). New mapping in the boundary region between a major Basin and Range fault, the Hart Mountain fault system (HFz), and the BFz was conducted to test this model and to determine the structural and temporal relationship between the two fault zones. Stratigraphic separation and topography were used to determine fault orientations, displacement gradients, and sense of motion in the two fault zones. N-S trending faults of the HFz show predominantly normal displacement. Displacement in the HFz decreases northward from a maximum of ~940 m at Hart Mountain to ~173 m to 0 m at the BFz. Fault orientations smoothly change from the N-S Basin and Range trend in the south to the NW BFz trend in the north. Topography and stratigraphic separation indicate that the BFz is a series of isolated faults with maximum slip of ~106 m and lengths of up to a few kilometers. Piercing points within the BFz indicate that down-to-the-north motion predominates with the fault system and that strike-slip motion is minimal. Uncertainty on observed fault displacements is + 5m. Stratigraphic separation of the Rattlesnake Tuff indicates that activity on the NW trending fault system post-dates the 7 Ma tuff. That displacement along the HFz effectively goes to zero at the BFz suggests Basin and Range faults have propagated northward into an existing northeast- facing extensional province represented by the BFz.

  2. SpectraCAM SPM: a camera system with high dynamic range for scientific and medical applications

    NASA Astrophysics Data System (ADS)

    Bhaskaran, S.; Baiko, D.; Lungu, G.; Pilon, M.; VanGorden, S.

    2005-08-01

    A scientific camera system having high dynamic range designed and manufactured by Thermo Electron for scientific and medical applications is presented. The newly developed CID820 image sensor with preamplifier-per-pixel technology is employed in this camera system. The 4 Mega-pixel imaging sensor has a raw dynamic range of 82dB. Each high-transparent pixel is based on a preamplifier-per-pixel architecture and contains two photogates for non-destructive readout of the photon-generated charge (NDRO). Readout is achieved via parallel row processing with on-chip correlated double sampling (CDS). The imager is capable of true random pixel access with a maximum operating speed of 4MHz. The camera controller consists of a custom camera signal processor (CSP) with an integrated 16-bit A/D converter and a PowerPC-based CPU running a Linux embedded operating system. The imager is cooled to -40C via three-stage cooler to minimize dark current. The camera housing is sealed and is designed to maintain the CID820 imager in the evacuated chamber for at least 5 years. Thermo Electron has also developed custom software and firmware to drive the SpectraCAM SPM camera. Included in this firmware package is the new Extreme DRTM algorithm that is designed to extend the effective dynamic range of the camera by several orders of magnitude up to 32-bit dynamic range. The RACID Exposure graphical user interface image analysis software runs on a standard PC that is connected to the camera via Gigabit Ethernet.

  3. LUMOS - A Sensitive and Reliable Optode System for Measuring Dissolved Oxygen in the Nanomolar Range

    PubMed Central

    Lehner, Philipp; Larndorfer, Christoph; Garcia-Robledo, Emilio; Larsen, Morten; Borisov, Sergey M.; Revsbech, Niels-Peter; Glud, Ronnie N.; Canfield, Donald E.; Klimant, Ingo

    2015-01-01

    Most commercially available optical oxygen sensors target the measuring range of 300 to 2 μmol L-1. However these are not suitable for investigating the nanomolar range which is relevant for many important environmental situations. We therefore developed a miniaturized phase fluorimeter based measurement system called the LUMOS (Luminescence Measuring Oxygen Sensor). It consists of a readout device and specialized “sensing chemistry” that relies on commercially available components. The sensor material is based on palladium(II)-5,10,15,20-tetrakis-(2,3,4,5,6-pentafluorphenyl)-porphyrin embedded in a Hyflon AD 60 polymer matrix and has a KSV of 6.25 x 10-3 ppmv-1. The applicable measurement range is from 1000 nM down to a detection limit of 0.5 nM. A second sensor material based on the platinum(II) analogue of the porphyrin is spectrally compatible with the readout device and has a measurement range of 20 μM down to 10 nM. The LUMOS device is a dedicated system optimized for a high signal to noise ratio, but in principle any phase flourimeter can be adapted to act as a readout device for the highly sensitive and robust sensing chemistry. Vise versa, the LUMOS fluorimeter can be used for read out of less sensitive optical oxygen sensors based on the same or similar indicator dyes, for example for monitoring oxygen at physiological conditions. The presented sensor system exhibits lower noise, higher resolution and higher sensitivity than the electrochemical STOX sensor previously used to measure nanomolar oxygen concentrations. Oxygen contamination in common sample containers has been investigated and microbial or enzymatic oxygen consumption at nanomolar concentrations is presented. PMID:26029920

  4. Emergent ultra–long-range interactions between active particles in hybrid active–inactive systems

    PubMed Central

    Steimel, Joshua P.; Aragones, Juan L.; Hu, Helen; Qureshi, Naser; Alexander-Katz, Alfredo

    2016-01-01

    Particle–particle interactions determine the state of a system. Control over the range of such interactions as well as their magnitude has been an active area of research for decades due to the fundamental challenges it poses in science and technology. Very recently, effective interactions between active particles have gathered much attention as they can lead to out-of-equilibrium cooperative states such as flocking. Inspired by nature, where active living cells coexist with lifeless objects and structures, here we study the effective interactions that appear in systems composed of active and passive mixtures of colloids. Our systems are 2D colloidal monolayers composed primarily of passive (inactive) colloids, and a very small fraction of active (spinning) ferromagnetic colloids. We find an emergent ultra–long-range attractive interaction induced by the activity of the spinning particles and mediated by the elasticity of the passive medium. Interestingly, the appearance of such interaction depends on the spinning protocol and has a minimum actuation timescale below which no attraction is observed. Overall, these results clearly show that, in the presence of elastic components, active particles can interact across very long distances without any chemical modification of the environment. Such a mechanism might potentially be important for some biological systems and can be harnessed for newer developments in synthetic active soft materials. PMID:27071096

  5. Emergent ultra-long-range interactions between active particles in hybrid active-inactive systems

    NASA Astrophysics Data System (ADS)

    Steimel, Joshua P.; Aragones, Juan L.; Hu, Helen; Qureshi, Naser

    2016-04-01

    Particle-particle interactions determine the state of a system. Control over the range of such interactions as well as their magnitude has been an active area of research for decades due to the fundamental challenges it poses in science and technology. Very recently, effective interactions between active particles have gathered much attention as they can lead to out-of-equilibrium cooperative states such as flocking. Inspired by nature, where active living cells coexist with lifeless objects and structures, here we study the effective interactions that appear in systems composed of active and passive mixtures of colloids. Our systems are 2D colloidal monolayers composed primarily of passive (inactive) colloids, and a very small fraction of active (spinning) ferromagnetic colloids. We find an emergent ultra-long-range attractive interaction induced by the activity of the spinning particles and mediated by the elasticity of the passive medium. Interestingly, the appearance of such interaction depends on the spinning protocol and has a minimum actuation timescale below which no attraction is observed. Overall, these results clearly show that, in the presence of elastic components, active particles can interact across very long distances without any chemical modification of the environment. Such a mechanism might potentially be important for some biological systems and can be harnessed for newer developments in synthetic active soft materials.

  6. Energy saving mechanisms, collective behavior and the variation range hypothesis in biological systems: A review.

    PubMed

    Trenchard, Hugh; Perc, Matjaž

    2016-09-01

    Energy saving mechanisms are ubiquitous in nature. Aerodynamic and hydrodynamic drafting, vortice uplift, Bernoulli suction, thermoregulatory coupling, path following, physical hooks, synchronization, and cooperation are only some of the better-known examples. While drafting mechanisms also appear in non-biological systems such as sedimentation and particle vortices, the broad spectrum of these mechanisms appears more diversely in biological systems that include bacteria, spermatozoa, various aquatic species, birds, land animals, semi-fluid dwellers like turtle hatchlings, as well as human systems. We present the thermodynamic framework for energy saving mechanisms, and we review evidence in favor of the variation range hypothesis. This hypothesis posits that, as an evolutionary process, the variation range between strongest and weakest group members converges on the equivalent energy saving quantity that is generated by the energy saving mechanism. We also review self-organized structures that emerge due to energy saving mechanisms, including convective processes that can be observed in many systems over both short and long time scales, as well as high collective output processes in which a form of collective position locking occurs.

  7. Chondrocyte Viability After a Simulated Blast Exposure.

    PubMed

    Shaw, K Aaron; Johnson, Peter C; Williams, David; Zumbrun, Steven D; Topolski, Richard; Cameron, Craig D

    2017-07-01

    The effects of blast exposure have gained increasing interest in the military medical community with their continued occurrence on the battlefield. The impact of the direct and indirect energy imparted from blasts to hollow viscera, as well as closed head injuries, have been well studied. However, the injury to articular cartilage has not been investigated, despite previous correlations regarding the development of osteoarthritis. The purpose of this study was to assess the degree of injury to articular chondrocytes after exposure to a simulated blast overpressure wave. Fresh juvenile porcine stifle joints were subjected to a simulated blast overpressure wave utilizing a custom fabricated blast simulator with compressed gases, within the reported range of observed battlefield blasts. Chondrocyte viability was assessed with live/dead staining using ethidium homodimer-2 and calcien acetoxymethylester stain and confocal laser scanning microscopy, calculated as a ratio of dead chondrocytes to live chondrocytes. Testing was performed at time points of 2, 4, and 8 hours after blast exposure and was compared with unblasted control samples. Chondrocyte viability decreased after exposure to a blast overpressure wave when compared with control samples. The amount of death was greater closer to the articular surface and dissipated with increasing tissue depth. Chondrocyte death increased with time after exposure. Chondrocyte death is present after exposure to a simulated blast wave. There is an inverse relationship between chondrocyte viability and the depth from the articular surface. Additional studies are needed to further characterize dose and time effects of blast exposure. Reprint & Copyright © 2017 Association of Military Surgeons of the U.S.

  8. [Nicotinamide influence on pancreatic cells viability].

    PubMed

    Kuchmerovs'ka, T M; Donchenko, H V; Tykhonenko, T M; Huzyk, M M; Stavniĭchuk, R V; Ianits'ka, L V; Stepanenko, S P; Klymenko, A P

    2012-01-01

    The study was undertaken to investigate the modulating effect of nicotinamide (NAm) in different concentrations and under different glucose concentrations on the viability and oxidative stress induced by streptozotocin (STZ, 5 mmol/l) and hydrogen peroxide (H2O2, 100 micromol/l) on isolated rat pancreatic cells of the Langerhans islets in vitro. Cell viability did not depend on the concentration of glucose in the range of 5-20 mmol/l, and in subsequent studies we used glucose in concentration of 10 mmol/l to protect cells against its hypo- and hyperglycemic action. Cytoprotective effect of NAm in concentrations from 5 to 20 mmol/l on cells survival was the same. It was found that the destructive action of STZ and H2O2 during 24 hours on isolated cells of the pancreas resulted in the significant cell death. It was revealed that NAm in concentration of 5 mmol/l not only had cytoprotective effects against STZ and H2O2 but also partially reduced the level of oxidative stress in the investigated cells induced by these compounds. High concentration of NAm, 35 mmol/l, causes cytotoxic effect on the viability of pancreatic islet cells and increase of oxidative stress induced by STZ and H2O2. Most likely these effects could be associated with direct modulatory action of NAm on important effector mechanisms involved in cell death, including PARP-dependent processes, or/and indirectly, through metabolic and antioxidant effects of the compound.

  9. GENERAL: A Study on Stochastic Resonance in Biased Subdiffusive Smoluchowski Systems within Linear Response Range

    NASA Astrophysics Data System (ADS)

    Li, Yi-Juan; Kang, Yan-Mei

    2010-08-01

    The method of matrix continued fraction is used to investigate stochastic resonance (SR) in the biased subdiffusive Smoluchowski system within linear response range. Numerical results of linear dynamic susceptibility and spectral amplification factor are presented and discussed in two-well potential and mono-well potential with different subdiffusion exponents. Following our observation, the introduction of a bias in the potential weakens the SR effect in the subdiffusive system just as in the normal diffusive case. Our observation also discloses that the subdiffusion inhibits the low-frequency SR, but it enhances the high-frequency SR in the biased Smoluchowski system, which should reflect a “flattening" influence of the subdiffusion on the linear susceptibility.

  10. From phase separation to long-range order in a system of interacting electrons

    NASA Astrophysics Data System (ADS)

    Derzhko, Volodymyr; Jȩdrzejewski, Janusz

    2003-10-01

    We study a system composed of fermions (electrons), hopping on a square lattice, and of immobile particles (ions), that is described by the spinless Falicov-Kimball Hamiltonian augmented by a next-nearest-neighbor attractive interaction between the ions (a nearest-neighbor repulsive interaction between the ions can be included and does not alter the results). A part of the grand-canonical phase diagram of this system is constructed rigorously, when the coupling between the electrons and ions is much stronger than the hopping intensity of electrons. The obtained diagram implies that, at least for a few rational densities of particles, by increasing the hopping intensity the system can be driven from a state of phase separation to a state with a long-range order. This kind of transitions occurs also, when the hopping fermions are replaced by hopping hard-core bosons.

  11. Optical design and development of the Near Range Lidar system for aerosol investigation at Belsk

    NASA Astrophysics Data System (ADS)

    Posyniak, Michal; Piatruczuk, Aleksander; Szkop, Artur

    2015-04-01

    The development of the lidar system in the Central Geophysics Observatory at Belsk (Poland) is presented. Belsk is an aerosol background site located in a rural area about 50 km south from Warsaw. A new near range (NR) lidar was added to the existing far range (FR) lidar system to enable the acquisition of lidar signals at the distance of a few hundred meters from the device. In the existing design of the FR lidar a 600 mm diameter mirror was used which resultedin anoverlap over 1500 mmaking this device suitable for observations of aerosols in free troposphere and lower stratosphere but not in the Planetary Boundary Layer (PBL).To enable measurements in the PBL the near range detection systemwas designed as a complement of the existing FR lidar. A secondtelescope with a set of detectors was used with the same laser as in the FR system as a light source. The Nd:YAGpulselasergenerates three wavelengths (1064, 532 and 355 nm).Energies of light pulses are about 320 mJ while their repetition rate is 15 Hz. In the optical receiver of the NR lidar a telescope with a 150 mm diameter parabolic mirror with optical fiber (1 mm core diameter) as a field stop was used. Our analysis shows that full overlap of the laser beam and the NR telescope field of view is expected at about 150 m. A polichromator based on dichroic beam splitters and a set of narrow band pass filters were used to separate wavelengths. The design of the NR lidar easily allows to add Raman channels to the system. The acquisition of the analog lidar echoes was done by photomultipliers (at 355 and 532 nm) and the avalanche photodiode (at 1064 nm). 14 bit analog to digital converters coupled with PC computer by USB 2.0 were also used.

  12. White noise analysis of Phycomyces light growth response system. I. Normal intensity range.

    PubMed Central

    Lipson, E D

    1975-01-01

    The Wiener-Lee-Schetzen method for the identification of a nonlinear system through white gaussian noise stimulation was applied to the transient light growth response of the sporangiophore of Phycomyces. In order to cover a moderate dynamic range of light intensity I, the imput variable was defined to be log I. The experiments were performed in the normal range of light intensity, centered about I0 = 10(-6) W/cm2. The kernels of the Wierner functionals were computed up to second order. Within the range of a few decades the system is reasonably linear with log I. The main nonlinear feature of the second-order kernel corresponds to the property of rectification. Power spectral analysis reveals that the slow dynamics of the system are of at least fifth order. The system can be represented approximately by a linear transfer function, including a first-order high-pass (adaptation) filter with a 4 min time constant and an underdamped fourth-order low-pass filter. Accordingly a linear electronic circuit was constructed to simulate the small scale response characteristics. In terms of the adaptation model of Delbrück and Reichardt (1956, in Cellular Mechanisms in Differentiation and Growth, Princeton University Press), kernels were deduced for the dynamic dependence of the growth velocity (output) on the "subjective intensity", a presumed internal variable. Finally the linear electronic simulator above was generalized to accommodate the large scale nonlinearity of the adaptation model and to serve as a tool for deeper test of the model. PMID:1203444

  13. Environmental use of a Laser Range Finder and the Advanced Visualization System

    NASA Astrophysics Data System (ADS)

    Thornton, E. N.; Bohn, S.; Baker, C. P.; Jones, D. R.; Strope, L. A.

    1993-05-01

    The United States Department of Energy (DOE) is facing a large task in characterizing and remediating the contents of hazardous waste inside storage tanks. The characterization process of these tanks is a key step to the remediation process. Due to the hazardous materials inside the waste tanks, all of the work must be done remotely utilizing robotic systems. The Laser Range Finder (LRF) is a single point sensor used to remotely collect range and intensity data. The LRF sensor data is used to reconstruct the tank surface environment based on multiple LRF scans. This reconstructed surface definition can be used by a robotic controller to perform obstacle avoidance with items in the tank. The Pacific Northwest Laboratory (PNL) has used Advanced Visualization System (AVS) to prototype the filtering, transformation, and reconstructing process. AVS software modules have been written to address LRF filtering on both the range and intensity images. A coordinate transformation module was constructed to convert the raw LRF data into a Cartesian coordinate reference frame. The results of filtering and transforms are integrated into a master map of the tank using an octree database. Master octrees are traversed and made into AVS geometry to visualize the tank interior. The graphical display of the tank interior can be used for robotic path planning and monitoring waste removal progress.

  14. Confinement effects upon the separation of structural transitions in linear systems with restricted bond fluctuation ranges

    NASA Astrophysics Data System (ADS)

    Koci, Tomas; Bachmann, Michael

    2015-10-01

    By means of advanced parallel replica-exchange Monte Carlo methods we examine the influence of elasticity and confinement on the structural transitions of linear systems with restricted bonded interaction. For this purpose, we adopt a model for coarse-grained flexible polymers of finite length in the dilute regime. Hyperphase diagrams are constructed using energy-dependent canonical quantities to demonstrate the effects of the changes in the range of the confined interaction on the liquid and solid structural phases. With increasing bonded interaction range we observe the disappearance of the liquid phase and the fusion of the gas-liquid (or Θ ) and the liquid-solid transitions. One of the most remarkable features, the liquid-gas transition, changes from second to first order if the confined interaction range exceeds a threshold that separates polymeric from nonpolymeric systems. The notoriously difficult sampling of the entropically suppressed conformations in the region of very strong first-order transitions is improved by using multiple Gaussian modified ensembles.

  15. Analysis of the characteristics of GRACE dual one-way ranging system

    NASA Astrophysics Data System (ADS)

    Ko, Ung Dai

    The motivation for this research was an improvement of the quality of the Earth's gravity solutions from the GRACE mission data through an instrument-level study. The objective was a better understanding of the characteristics and sources of the high-frequency noise in the range of (0.02 ˜ 0.1 Hz) in the dual one-way ranging (DOWR) and its effect on the gravity solution. For this purpose, the mathematical model of the DOWR observation was derived and the Allan variance was computed to establish an upper bound on the level of frequency instability of the ultra-stable oscillators (USO) to determine their contribution to the high-frequency noise. Because they are dominated by the high-frequency noise, the postfit residuals of the time derivative of the DOWR ranges were also examined to evaluate the contributions of various other factors such as system noise from the microwave signal receiver, external influences, and internal influences. The results indicate that the system noise is the dominant source of the excessive high-frequency noise. As one method of mitigation, a tighter bandwidth filter was applied to the DOWR processing, resulting in modest improvements in gravity solutions.

  16. Environmental use of a Laser Range Finder and the Advanced Visualization System

    SciTech Connect

    Thornton, E.N.; Bohn, S.; Baker, C.P.; Jones, D.R.; Strope, L.A.

    1993-05-01

    The United States Department of Energy (DOE) is facing a large task in characterizing and remediating the contents of hazardous waste inside storage tanks. The characterization process of these tanks is a key step to the remediation process. Due to the hazardous materials inside the waste tanks, all of the work must be done remotely utilizing robotic systems. The Laser Range Finder (LRF) is a single point sensor used to remotely collect range and intensity data. The LRF sensor data is used to reconstruct the tank surface environment based on multiple LRF scans. This reconstructed surface definition can be used by a robotic controller to perform obstacle avoidance with items in the tank. The Pacific Northwest Laboratory (PNL) has used Advanced Visualization System (AVS) to prototype the filtering, transformation and reconstructing process. AVS software modules have been written to address LRF filtering on both the range and intensity images. A coordinate transformation module was constructed to convert the raw LRF data into a Cartesian coordinate reference frame. The results of filtering and transforms are integrated into a master map of the tank using an octree database. Master octrees are traversed and made into AVS geometry to visualize the tank interior. The graphical display of the tank interior can be used for robotic path planning and monitoring waste removal progress.

  17. Functional changes of the visual system of the damselfish Dascyllus marginatus along its bathymetric range.

    PubMed

    Brokovich, Eran; Ben-Ari, Tomer; Kark, Salit; Kiflawi, Moshe; Dishon, Gal; Iluz, David; Shashar, Nadav

    2010-11-02

    Shallow-water zooplanktivorous fish rely on their vision for foraging. In shallow water, feeding efficiency decreases in dim light and thus the fish cease foraging at crepuscular hours. Creatures living in the lower parts of their depth ranges are expected to be exposed to limited light levels for longer hours. However, observations of the zooplanktivore Dascyllus marginatus showed little change in foraging duration down to 40m deep. We asked whether the visual system's functionality changes with depth along the depth range of this damselfish; we examined eye and retina anatomy for changes in visual acuity and light sensitivity and used the optomotor response to test for spatial and temporal light summation. We found only minor changes in the anatomy of the eye that are not expected to affect visual sensitivity or acuity. However, behavioural experiments showed that the deeper water fish's test performance exceeded those of fish in shallow water under lower light levels. We found that deeper water fish responded to the optomotor test at lower light levels and also had more discriminating visual acuity in low light, which can increase their potential reactive distance. The plastic adaptive ability of the visual system to low light levels may explain the fish's ability to inhabit deeper reef habitats and thus expand their depth range limits.

  18. Low-power wide-locking-range injection-locked frequency divider for OFDM UWB systems

    NASA Astrophysics Data System (ADS)

    Jiangwei, Yin; Ning, Li; Renliang, Zheng; Wei, Li; Junyan, Ren

    2009-05-01

    This paper describes a divide-by-two injection-locked frequency divider (ILFD) for frequency synthesizers as used in multiband orthogonal frequency division multiplexing (OFDM) ultra-wideband (UWB) systems. By means of dual-injection technique and other conventional tuning techniques, such as DCCA and varactor tuning, the divider demonstrates a wide locking range while consuming much less power. The chip was fabricated in the Jazz 0.18 μm RF CMOS process. The measurement results show that the divider achieves a locking range of 4.85 GHz (6.23 to 11.08 GHz) at an input power of 8 dBm. The core circuit without the test buffer consumes only 3.7 mA from a 1.8 V power supply and has a die area of 0.38 × 0.28 mm2. The wide locking range combined with low power consumption makes the ILFD suitable for its application in UWB systems.

  19. Range and Size Estimation Based on a Coordinate Transformation Model for Driving Assistance Systems

    NASA Astrophysics Data System (ADS)

    Wu, Bing-Fei; Lin, Chuan-Tsai; Chen, Yen-Lin

    This paper presents new approaches for the estimation of range between the preceding vehicle and the experimental vehicle, estimation of vehicle size and its projective size, and dynamic camera calibration. First, our proposed approaches adopt a camera model to transform coordinates from the ground plane onto the image plane to estimate the relative position between the detected vehicle and the camera. Then, to estimate the actual and projective size of the preceding vehicle, we propose a new estimation method. This method can estimate the range from a preceding vehicle to the camera based on contact points between its tires and the ground and then estimate the actual size of the vehicle according to the positions of its vertexes in the image. Because the projective size of a vehicle varies with respect to its distance to the camera, we also present a simple and rapid method of estimating a vehicle's projective height, which allows a reduction in computational time for size estimation in real-time systems. Errors caused by the application of different camera parameters are also estimated and analyzed in this study. The estimation results are used to determine suitable parameters during camera installation to suppress estimation errors. Finally, to guarantee robustness of the detection system, a new efficient approach to dynamic calibration is presented to obtain accurate camera parameters, even when they are changed by camera vibration owing to on-road driving. Experimental results demonstrate that our approaches can provide accurate and robust estimation results of range and size of target vehicles.

  20. Laser triangulation range finder based on a chaotic modulation and detection system

    NASA Astrophysics Data System (ADS)

    Stefani, Mario A.; Pizolato, Jose C., Jr.; Neto, Luiz G.

    2000-08-01

    A laser triangulation range finder based on a chaotic and detection scheme is presented. An elementary non-linear electronic oscillator composed by two operation amplifiers with feedback current form two antiparallel diodes generates a chaotic signal that is used to generate a chaotic clock modulation with a well-defined broad band spectrum. This chaotic clock modulates a laser beam that is transmitted and received by a collecting optics in a laser triangulation range finder scheme. A band limited phase delay equalized amplifier sends the received signal to a balanced demodulator using the same chaotic generated signal as 'local oscillator'. A low pass filter is tuned to assure good compromise against noise immunity and the desired response speed. This modulator scheme allows several laser stations to operate in same working area, avoiding carefully adjusted field-of-view screening and cross-detection false alarm due to the interference of other laser stations. The chaotic modulator can be used as an alternative for microprocessor based pseudo random sequence generator when board space or cost is a critical system specification. The laser triangulation range finder has a range of 0.5m to 2m using a 3mW class IIIa visible laser, with precision of 5 mm.

  1. Automated, long-range, night/day, active-SWIR face recognition system

    NASA Astrophysics Data System (ADS)

    Lemoff, Brian E.; Martin, Robert B.; Sluch, Mikhail; Kafka, Kristopher M.; Dolby, Andrew; Ice, Robert

    2014-06-01

    Covert, long-range, night/day identification of stationary human subjects using face recognition has been previously demonstrated using the active-SWIR Tactical Imager for Night/Day Extended-Range Surveillance (TINDERS) system. TINDERS uses an invisible, eye-safe, SWIR laser illuminator to produce high-quality facial imagery under conditions ranging from bright sunlight to total darkness. The recent addition of automation software to TINDERS has enabled the autonomous identification of moving subjects at distances greater than 100 m. Unlike typical cooperative, short range face recognition scenarios, where positive identification requires only a single face image, the SWIR wavelength, long distance, and uncontrolled conditions mean that positive identification requires fusing the face matching results from multiple captured images of a single subject. Automation software is required to initially detect a person, lock on and track the person as they move, and select video frames containing high-quality frontal face images for processing. Fusion algorithms are required to combine the matching results from multiple frames to produce a high-confidence match. These automation functions will be described, and results showing automated identification of moving subjects, night and day, at multiple distances will be presented.

  2. Multi-focus, high resolution inspection system for extended range applications

    NASA Astrophysics Data System (ADS)

    Harding, Kevin

    2016-05-01

    Visual inspection of parts or structures for defects typically requires good spatial resolution to see the defects, but may also require a large focus range. But to obtain the best resolution from an imaging system, it needs to have a low f-number which limits the usable depth of field. Methods to use autofocus or focus stacking provides more range at high resolution, but often at the expense of computation time, loss of a real time image and uncertainty in scale changes. This paper describes an approach to quickly move through a range of focus positions without the need to move optics mechanically in a manner that is highly repeatable, maintains high resolution and provides the potential for a live image directly viewable by an inspector, even at microscope level magnifications. This paper will present the approach we investigated and discuss the pros and cons for a range of applications from large structures to small feature inspection. The paper will present examples of what resolution was achieved and how the multiple images might also be used to determine other parameters such as pose of a test surface.

  3. Development of Algorithms and Error Analyses for the Short Baseline Lightning Detection and Ranging System

    NASA Technical Reports Server (NTRS)

    Starr, Stanley O.

    1998-01-01

    NASA, at the John F. Kennedy Space Center (KSC), developed and operates a unique high-precision lightning location system to provide lightning-related weather warnings. These warnings are used to stop lightning- sensitive operations such as space vehicle launches and ground operations where equipment and personnel are at risk. The data is provided to the Range Weather Operations (45th Weather Squadron, U.S. Air Force) where it is used with other meteorological data to issue weather advisories and warnings for Cape Canaveral Air Station and KSC operations. This system, called Lightning Detection and Ranging (LDAR), provides users with a graphical display in three dimensions of 66 megahertz radio frequency events generated by lightning processes. The locations of these events provide a sound basis for the prediction of lightning hazards. This document provides the basis for the design approach and data analysis for a system of radio frequency receivers to provide azimuth and elevation data for lightning pulses detected simultaneously by the LDAR system. The intent is for this direction-finding system to correct and augment the data provided by LDAR and, thereby, increase the rate of valid data and to correct or discard any invalid data. This document develops the necessary equations and algorithms, identifies sources of systematic errors and means to correct them, and analyzes the algorithms for random error. This data analysis approach is not found in the existing literature and was developed to facilitate the operation of this Short Baseline LDAR (SBLDAR). These algorithms may also be useful for other direction-finding systems using radio pulses or ultrasonic pulse data.

  4. SLR2000: a microlaser-based single photoelectron satellite laser ranging system

    NASA Technical Reports Server (NTRS)

    Degnan, John J.; McGarry, Jan F.

    1998-01-01

    SLR2000 is an autonomous and eyesafe satellite laser ranging (SLR) station with an expected single shot range precision of about one centimeter and a normal point (time-averaged) precision better than 3 mm. The system wil provide continuous 24 hour tracking coverage for a constellation of over twenty artificial satellites. Replication costs are expected to be roughly an order of magnitude less than current operational systems, and the system will be about 75% less expensive to operate and maintain relative to manned systems. Computer simulations have predicted a daylight tracking capability to GPS and lower satellites with telescope apertures of 40 cm and have demonstrated the ability of our current autotracking algorithm to extract mean signal strengths below .001 photoelectrons per pulse from daytime background noise. The dominant cost driver in present SLR systems is the onsite and central infrastructure manpower required to operate the system, to service and maintain the complex subsystems, and to ensure that the transmitted laser beam is not a hazard to onsite personnel or to overflying aircraft. To keep development, fabrication, and maintenance costs at a minimum, we adopted the following design philosophies: (1) use off the shelf commercial components wherever possible; this allows rapid component replacement and "outsourcing" of engineering support; (2) use smaller telescopes (less than 50 cm) since this constrains the cost, size, and weight of the telescope and tracking mount; and (3) for low maintenance and failsafe reliability, choose simple versus complex technical approaches and, where possible, use passive techniques and components rather than active ones. Adherence to these philosophies has led to the SLR2000 design described here.

  5. Dynamics and thermodynamics of systems with long-range dipole-type interactions.

    PubMed

    Atenas, Boris; Curilef, Sergio

    2017-02-01

    A Hamiltonian mean field model, where the potential is inspired by dipole-dipole interactions, is proposed to characterize the behavior of systems with long-range interactions. The dynamics of the system remains in quasistationary states before arriving at equilibrium. The equilibrium is analytically derived from the canonical ensemble and coincides with that obtained from molecular dynamics simulations (microcanonical ensemble) at only long time scales. The dynamics of the system is characterized by the behavior of the mean value of the kinetic energy. The significance of the results, compared to others in the recent literature, is that two plateaus sequentially emerge in the evolution of the model under the special considerations of the initial conditions and systems of finite size. The first plateau decays to a different second one before the system reaches equilibrium, but the dynamics of the system is expected to have only one plateau when the thermodynamics limit is reached because the difference between them tends to disappear as N tends to infinity. Hence, the first plateau is a type of quasistationary state the lifetime of which depends on a power law of N and the second seems to be a true quasistationary state as reported in the literature. We characterize the general behavior of the model according to its dynamics and thermodynamics.

  6. Dynamics and thermodynamics of systems with long-range dipole-type interactions

    NASA Astrophysics Data System (ADS)

    Atenas, Boris; Curilef, Sergio

    2017-02-01

    A Hamiltonian mean field model, where the potential is inspired by dipole-dipole interactions, is proposed to characterize the behavior of systems with long-range interactions. The dynamics of the system remains in quasistationary states before arriving at equilibrium. The equilibrium is analytically derived from the canonical ensemble and coincides with that obtained from molecular dynamics simulations (microcanonical ensemble) at only long time scales. The dynamics of the system is characterized by the behavior of the mean value of the kinetic energy. The significance of the results, compared to others in the recent literature, is that two plateaus sequentially emerge in the evolution of the model under the special considerations of the initial conditions and systems of finite size. The first plateau decays to a different second one before the system reaches equilibrium, but the dynamics of the system is expected to have only one plateau when the thermodynamics limit is reached because the difference between them tends to disappear as N tends to infinity. Hence, the first plateau is a type of quasistationary state the lifetime of which depends on a power law of N and the second seems to be a true quasistationary state as reported in the literature. We characterize the general behavior of the model according to its dynamics and thermodynamics.

  7. A Non-Contact Measurement System for the Range of Motion of the Hand

    PubMed Central

    Pham, Trieu; Pathirana, Pubudu N.; Trinh, Hieu; Fay, Pearse

    2015-01-01

    An accurate and standardised tool to measure the active range of motion (ROM) of the hand is essential to any progressive assessment scenario in hand therapy practice. Goniometers are widely used in clinical settings for measuring the ROM of the hand. However, such measurements have limitations with regard to inter-rater and intra-rater reliability and involve direct physical contact with the hand, possibly increasing the risk of transmitting infections. The system proposed in this paper is the first non-contact measurement system utilising Intel Perceptual Technology and a Senz3D Camera for measuring phalangeal joint angles. To enhance the accuracy of the system, we developed a new approach to achieve the total active movement without measuring three joint angles individually. An equation between the actual spacial position and measurement value of the proximal inter-phalangeal joint was established through the measurement values of the total active movement, so that its actual position can be inferred. Verified by computer simulations, experimental results demonstrated a significant improvement in the calculation of the total active movement and successfully recovered the actual position of the proximal inter-phalangeal joint angles. A trial that was conducted to examine the clinical applicability of the system involving 40 healthy subjects confirmed the practicability and consistency in the proposed system. The time efficiency conveyed a stronger argument for this system to replace the current practice of using goniometers. PMID:26225976

  8. Prototype system for proton beam range measurement based on gamma electron vertex imaging

    NASA Astrophysics Data System (ADS)

    Lee, Han Rim; Kim, Sung Hun; Park, Jong Hoon; Jung, Won Gyun; Lim, Hansang; Kim, Chan Hyeong

    2017-06-01

    In proton therapy, for both therapeutic effectiveness and patient safety, it is very important to accurately measure the proton dose distribution, especially the range of the proton beam. For this purpose, recently we proposed a new imaging method named gamma electron vertex imaging (GEVI), in which the prompt gammas emitting from the nuclear reactions of the proton beam in the patient are converted to electrons, and then the converted electrons are tracked to determine the vertices of the prompt gammas, thereby producing a 2D image of the vertices. In the present study, we developed a prototype GEVI system, including dedicated signal processing and data acquisition systems, which consists of a beryllium plate (= electron converter) to convert the prompt gammas to electrons, two double-sided silicon strip detectors (= hodoscopes) to determine the trajectories of those converted electrons, and a plastic scintillation detector (= calorimeter) to measure their kinetic energies. The system uses triple coincidence logic and multiple energy windows to select only the events from prompt gammas. The detectors of the prototype GEVI system were evaluated for electronic noise level, energy resolution, and time resolution. Finally, the imaging capability of the GEVI system was tested by imaging a 90Sr beta source, a 60Co gamma source, and a 45-MeV proton beam in a PMMA phantom. The overall results of the present study generally show that the prototype GEVI system can image the vertices of the prompt gammas produced by the proton nuclear interactions.

  9. A Non-Contact Measurement System for the Range of Motion of the Hand.

    PubMed

    Pham, Trieu; Pathirana, Pubudu N; Trinh, Hieu; Fay, Pearse

    2015-07-28

    An accurate and standardised tool to measure the active range of motion (ROM) of the hand is essential to any progressive assessment scenario in hand therapy practice. Goniometers are widely used in clinical settings for measuring the ROM of the hand. However, such measurements have limitations with regard to inter-rater and intra-rater reliability and involve direct physical contact with the hand, possibly increasing the risk of transmitting infections. The system proposed in this paper is the first non-contact measurement system utilising Intel Perceptual Technology and a Senz3D Camera for measuring phalangeal joint angles. To enhance the accuracy of the system, we developed a new approach to achieve the total active movement without measuring three joint angles individually. An equation between the actual spacial position and measurement value of the proximal inter-phalangeal joint was established through the measurement values of the total active movement, so that its actual position can be inferred. Verified by computer simulations, experimental results demonstrated a significant improvement in the calculation of the total active movement and successfully recovered the actual position of the proximal inter-phalangeal joint angles. A trial that was conducted to examine the clinical applicability of the system involving 40 healthy subjects confirmed the practicability and consistency in the proposed system. The time efficiency conveyed a stronger argument for this system to replace the current practice of using goniometers.

  10. Dual-system Tectonics of the San Luis Range and Vicinity, Coastal Central California

    NASA Astrophysics Data System (ADS)

    Hamilton, D. H.

    2010-12-01

    The M 6.5 "San Simeon" earthquake of December 22, 2003, occurred beneath the Santa Lucia Range in coastal central California, and resulted in around $250,000,000 property damage and two deaths from collapse of an historic building in the town of Paso Robles, located 40 km from the epicenter. The earthquake and more than 10,000 aftershocks were well recorded by nearby seismographs, which permitted detailed analysis of the event (eg: McLaren et al., 2008). This analysis facilitated evaluation of the hazard of the occurrence of a similar event in the nearby San Luis Range, located along the coast west of the city of San Luis Obispo some 55 km south of the San Simeon epicenter. The future occurrence of earthquakes analogous to the 2003 event in this area had been proposed in the late 1960’s (eg: Benioff and Smith, 1967; Richter, 1969) but the apparent hazard of such occurrences came to be overshadowed by the discovery of the “Hosgri” strike slip fault passing close to the area in the offshore. However data accumulated since the early 1970’s clearly demonstrate the hazard as being partitioned between nearby earthquakes of strike slip origin, and underlying earthquakes of thrust origin analogous to that of the 2003 San Simeon earthquake. And for the onshore San Luis Range area, an underlying actively seismogenic thrust wedge appears to provide the maximum potential seismic ground motion; exceeding that potentially resulting from large events on nearby strike slip faults of the San Simeon-Hosgri system, for onshore sites. Understanding and documentation of the geology, geomorphology, tectonics and seismogenesis of the San Luis Range and vicinity has recently experienced a quantum improvement as both new and accumulated data have been analysed. An integrated interpretation of all available data now clearly shows that a dual “side by side” system of active tectonics exists in the region. Essentially the most obvious evidence for this is seen simply in the

  11. Predicting the phase diagram of two-dimensional colloidal systems with long-range interactions.

    PubMed

    Mejía-Rosales, Sergio J; Gil-Villegas, Alejandro; Ivlev, Boris I; Ruiz-García, Jaime

    2006-11-09

    The phase diagram of a two-dimensional model system for colloidal particles at the air-water interface was determined using Monte Carlo computer simulations in the isothermic-isobaric ensemble. The micrometer-range binary colloidal interaction has been modeled by hard disklike particles interacting via a secondary minimum followed by a weaker longer-range repulsive maximum, both of the order of kBT. The repulsive part of the potential drives the clustering of particles at low densities and low temperatures. Pinned voids are formed at higher densities and intermediate values of the surface pressure. The analysis of isotherms, translational and orientational correlation functions as well as structure factor gives clear evidence of the presence of a melting first-order transition. However, the melting process can be also followed by a metastable route through a hexatic phase at low surface pressures and low temperatures, before crystalization occurs at higher surface pressure.

  12. Global positioning system reoccupation of early triangulation sites - Tectonic deformation of the Southern Coast Ranges

    NASA Technical Reports Server (NTRS)

    Shen, Zheng-Kang; Jackson, David D.

    1993-01-01

    We study tectonic deformation in the Southern Coast Range, California. We use triangulation and astronomic azimuth data collected since 1875, trilateration since 1970, and global positioning system data collected from 1986 to 1987. Two modeling techniques have been used. An elastic block-fault model is applied to study the tectonic motion of the San Andreas Fault and the San Gregorio-Hosgri Fault. Station velocities are modeled to study regional deformations. Results show that the regional deformation is predominantly controlled by deep strike-slip motion along the San Andreas Fault, at a rate of 33 +/- 2 mm/yr. Deep slip along the San Gregorio-Hosgri Fault is about 0-4 mm/yr, assuming a locked suit to a depth of 20 km. Convergence normal to the San Andreas Fault in the Southern Coast Ranges is not greater than 0.02 microrad/yr.

  13. Bounding the Failure Probability Range of Polynomial Systems Subject to P-box Uncertainties

    NASA Technical Reports Server (NTRS)

    Crespo, Luis G.; Kenny, Sean P.; Giesy, Daniel P.

    2012-01-01

    This paper proposes a reliability analysis framework for systems subject to multiple design requirements that depend polynomially on the uncertainty. Uncertainty is prescribed by probability boxes, also known as p-boxes, whose distribution functions have free or fixed functional forms. An approach based on the Bernstein expansion of polynomials and optimization is proposed. In particular, we search for the elements of a multi-dimensional p-box that minimize (i.e., the best-case) and maximize (i.e., the worst-case) the probability of inner and outer bounding sets of the failure domain. This technique yields intervals that bound the range of failure probabilities. The offset between this bounding interval and the actual failure probability range can be made arbitrarily tight with additional computational effort.

  14. Noise-induced dynamical phase transitions in long-range systems.

    PubMed

    Chavanis, Pierre-Henri; Baldovin, Fulvio; Orlandini, Enzo

    2011-04-01

    In the thermodynamic limit, the time evolution of isolated long-range interacting systems is properly described by the Vlasov equation. This equation admits nonequilibrium dynamically stable stationary solutions characterized by a zero order parameter. We show that the presence of external noise sources, such as a heat bath, can reduce their lifetime and induce at a specific time a dynamical phase transition marked by a nonzero order parameter. This transition may be used as a distinctive experimental signature of the temporary existence of nonequilibrium Vlasov-stable states. In particular, we present evidence of a regime characterized by an order parameter pulse. Our analytical results are corroborated by numerical simulations of a paradigmatic long-range model.

  15. Code regenerative clean-up loop transponder for a mu-type ranging system

    NASA Technical Reports Server (NTRS)

    Hurd, W. J. (Inventor)

    1973-01-01

    A loop transponder for regenerating the code of a mu type ranging system is disclosed. It includes a phase locked loop, a code generator, and a loop detector. The function of the phase locked loop is to provide phase lock between a received component wk of the range signal and a replica rafter wk of the received component, provided by the code generator. The code generator also provides a replica of the next component rafter w(w+1). The loop detector responds to wk rafler wk and rafter w(k+1) to determine when the next component w(k+1) is received and controls the code generator to supply w(k+1) to the phase locked loop and to generate a replica rafter w(k+2) of the next component.

  16. Precise control of coupling strength in photonic molecules over a wide range using nanoelectromechanical systems

    PubMed Central

    Du, Han; Zhang, Xingwang; Chen, Guoqiang; Deng, Jie; Chau, Fook Siong; Zhou, Guangya

    2016-01-01

    Photonic molecules have a range of promising applications including quantum information processing, where precise control of coupling strength is critical. Here, by laterally shifting the center-to-center offset of coupled photonic crystal nanobeam cavities, we demonstrate a method to precisely and dynamically control the coupling strength of photonic molecules through integrated nanoelectromechanical systems with a precision of a few GHz over a range of several THz without modifying the nature of their constituent resonators. Furthermore, the coupling strength can be tuned continuously from negative (strong coupling regime) to zero (weak coupling regime) and further to positive (strong coupling regime) and vice versa. Our work opens a door to the optimization of the coupling strength of photonic molecules in situ for the study of cavity quantum electrodynamics and the development of efficient quantum information devices. PMID:27097883

  17. Synthetic Scene Generation of Stennis Target Range for the Calibration of Remote Sensing Systems

    NASA Technical Reports Server (NTRS)

    Cao, Chang-Yong; Blonski, Slawomir; Ryan, Robert; Gasser, Gerald; Zanoni, Vicki; Jenner, Jeff

    1999-01-01

    The validation and verification (V&V) target range developed at Stennis Space Center is a useful tool for the calibration of remote sensing systems. In this paper, we present an algorithm for generating synthetic scenes or digital models of this target range. The atmospheric radiative transfer code Modtran 4 is used in simulating at-sensor radiance for a given sensor. Software is developed to generate the scene with different spatial and spectral resolutions using the at-sensor radiance values. Synthetic scenes provide a cost-effective way for in-flight validation for the spatial and radiometric accuracy of the data. Other applications include mission planning, sensor simulation, and trade-off analysis in sensor design. The radiometric and spatial accuracy of the simulation is evaluated by comparing simulated scenes with AVIRIS acquired values.

  18. Global positioning system reoccupation of early triangulation sites - Tectonic deformation of the Southern Coast Ranges

    NASA Technical Reports Server (NTRS)

    Shen, Zheng-Kang; Jackson, David D.

    1993-01-01

    We study tectonic deformation in the Southern Coast Range, California. We use triangulation and astronomic azimuth data collected since 1875, trilateration since 1970, and global positioning system data collected from 1986 to 1987. Two modeling techniques have been used. An elastic block-fault model is applied to study the tectonic motion of the San Andreas Fault and the San Gregorio-Hosgri Fault. Station velocities are modeled to study regional deformations. Results show that the regional deformation is predominantly controlled by deep strike-slip motion along the San Andreas Fault, at a rate of 33 +/- 2 mm/yr. Deep slip along the San Gregorio-Hosgri Fault is about 0-4 mm/yr, assuming a locked suit to a depth of 20 km. Convergence normal to the San Andreas Fault in the Southern Coast Ranges is not greater than 0.02 microrad/yr.

  19. 26 CFR 1.167(l)-4 - Public utility property; election to use asset depreciation range system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... depreciation range system. 1.167(l)-4 Section 1.167(l)-4 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT... Individuals and Corporations § 1.167(l)-4 Public utility property; election to use asset depreciation range system. (a) Application of section 167(l) to certain property subject to asset depreciation range...

  20. Real-time image processing of TOF range images using a reconfigurable processor system

    NASA Astrophysics Data System (ADS)

    Hussmann, S.; Knoll, F.; Edeler, T.

    2011-07-01

    During the last years, Time-of-Flight sensors achieved a significant impact onto research fields in machine vision. In comparison to stereo vision system and laser range scanners they combine the advantages of active sensors providing accurate distance measurements and camera-based systems recording a 2D matrix at a high frame rate. Moreover low cost 3D imaging has the potential to open a wide field of additional applications and solutions in markets like consumer electronics, multimedia, digital photography, robotics and medical technologies. This paper focuses on the currently implemented 4-phase-shift algorithm in this type of sensors. The most time critical operation of the phase-shift algorithm is the arctangent function. In this paper a novel hardware implementation of the arctangent function using a reconfigurable processor system is presented and benchmarked against the state-of-the-art CORDIC arctangent algorithm. Experimental results show that the proposed algorithm is well suited for real-time processing of the range images of TOF cameras.

  1. Ultrasonic Multiple-Access Ranging System Using Spread Spectrum and MEMS Technology for Indoor Localization

    PubMed Central

    Segers, Laurent; Tiete, Jelmer; Braeken, An; Touhafi, Abdellah

    2014-01-01

    Indoor localization of persons and objects poses a great engineering challenge. Previously developed localization systems demonstrate the use of wideband techniques in ultrasound ranging systems. Direct sequence and frequency hopping spread spectrum ultrasound signals have been proven to achieve a high level of accuracy. A novel ranging method using the frequency hopping spread spectrum with finite impulse response filtering will be investigated and compared against the direct sequence spread spectrum. In the first setup, distances are estimated in a single-access environment, while in the second setup, two senders and one receiver are used. During the experiments, the micro-electromechanical systems are used as ultrasonic sensors, while the senders were implemented using field programmable gate arrays. Results show that in a single-access environment, the direct sequence spread spectrum method offers slightly better accuracy and precision performance compared to the frequency hopping spread spectrum. When two senders are used, measurements point out that the frequency hopping spread spectrum is more robust to near-far effects than the direct sequence spread spectrum. PMID:24553084

  2. Location of the Fisher-Widom line for systems interacting through short-ranged potentials

    SciTech Connect

    Vega, C.; Rull, L.F.; Lago, S. |

    1995-04-01

    For finite-ranged potentials the behavior of the total correlation function {ital h}({ital r}) at large distances can be of two different types. In three-dimensional systems at low densities the function {ital r} {ital h}({ital r}) presents exponential decay whereas at high densities it presents exponentially damped oscillatory decay. The locus of points on the phase diagram where a transition from exponential to oscillatory decay occurs is denoted as the Fisher-Widom line after the work of these authors [M. E. Fisher and B. Widom, J. Chem. Phys. 50, 3756 (1969)]. These authors exactly computed the Fisher-Widom line for several one-dimensional systems and conjectured that the same behavior could occur in three dimensions. In this work the Fisher-Widom line is computed for a three-dimensional finite-range potential by using the structural information obtained from the reference hypernetted chain theory which is probably the most successful theory of liquid structure available now. By combining these results with computer simulations of the vapor-liquid equilibria of the considered model the Fisher-Widom line is located within the phase diagram of the model. For the considered model the Fisher-Widom line cuts the liquid branch of the vapor liquid equilibria at a reduced temperature of {ital T}/{ital T}{sub {ital c}}=0.88 and a reduced density of {rho}/{rho}{sub {ital c}}=2.07. The effect of the range of the potential on the location of the Fisher-Widom line is also considered. Increasing the range of the potential reduces the region of the phase diagram where oscillatory behavior of the function {ital r} {ital h}({ital r}) occurs. The long-range decay of a Lennard Jones fluid is also considered. Decay of {ital h}({ital r}) to zero at large distances is different for a Lennard-Jones potential and for a finite-ranged potential. (Abstract Truncated)

  3. Dynamics of Salmonella Shedding and Welfare of Hens in Free-Range Egg Production Systems

    PubMed Central

    Gole, Vaibhav C.; Woodhouse, Rebecca; Caraguel, Charles; Moyle, Talia; Rault, Jean-Loup; Sexton, Margaret

    2016-01-01

    ABSTRACT The current study investigated the effect of environmental stressors (i.e., weather changes) on Salmonella shedding in free-range production systems and the correlations with behavioral and physiological measures (i.e., fecal glucocorticoid metabolites). This involved longitudinal and point-in-time surveys of Salmonella shedding and environmental contamination on four commercial free-range layer farms. The shedding of Salmonella was variable across free-range farms and in different seasons. There was no significant effect of season on the Salmonella prevalence during this investigation. In this study, the combined Salmonella most probable number (MPN) counts in environmental (including feces, egg belt, dust, nest box, and ramp) samples were highest in samples collected during the summer season (4th sampling, performed in February). The predominant serovars isolated during this study were Salmonella enterica serovar Mbandaka and Salmonella enterica serovar Typhimurium phage types 135 and 135a. These two phage types were involved in several egg product-related Salmonella outbreaks in humans. Multilocus variable-number tandem-repeat analysis (MLVA) results indicated that MLVA types detected from human food poisoning cases exhibited MLVA patterns similar to the strains isolated during this study. All Salmonella isolates (n = 209) were tested for 15 different genes involved in adhesion, invasion, and survival of Salmonella spp. We also observed variations for sopA, ironA, and misL. There were no positive correlations between fecal corticosterone metabolite (FCM) and Salmonella prevalence and/or shedding in feces. Also, there were no positive correlations between Salmonella prevalence and Salmonella count (log MPN) and any of the other welfare parameters. IMPORTANCE In this study, the welfare of laying hens and Salmonella shedding were compared over a prolonged period of time in field conditions. This study investigated the long-term shedding of Salmonella

  4. HiRes camera and LIDAR ranging system for the Clementine mission

    SciTech Connect

    Ledebuhr, A.G.; Kordas, J.F.; Lewis, I.T.

    1995-04-01

    Lawrence Livermore National Laboratory developed a space-qualified High Resolution (HiRes) imaging LIDAR (Light Detection And Ranging) system for use on the DoD Clementine mission. The Clementine mission provided more than 1.7 million images of the moon, earth, and stars, including the first ever complete systematic surface mapping of the moon from the ultra-violet to near-infrared spectral regions. This article describes the Clementine HiRes/LIDAR system, discusses design goals and preliminary estimates of on-orbit performance, and summarizes lessons learned in building and using the sensor. The LIDAR receiver system consists of a High Resolution (HiRes) imaging channel which incorporates an intensified multi-spectral visible camera combined with a Laser ranging channel which uses an avalanche photo-diode for laser pulse detection and timing. The receiver was bore sighted to a light-weight McDonnell-Douglas diode-pumped ND:YAG laser transmitter that emmitted 1.06 {micro}m wavelength pulses of 200 mJ/pulse and 10 ns pulse-width, The LIDAR receiver uses a common F/9.5 Cassegrain telescope assembly. The optical path of the telescope is split using a color-separating beamsplitter. The imaging channel incorporates a filter wheel assembly which spectrally selects the light which is imaged onto a custom 12 mm gated image intensifier fiber-optically-coupled into a 384 x 276 pixel frame transfer CCD FPA. The image intensifier was spectrally sensitive over the 0.4 to 0.8 {micro}m wavelength region. The six-position filter wheel contained 4 narrow spectral filters, one broadband and one blocking filter. At periselene (400 km) the HiRes/LIDAR imaged a 2.8 km swath width at 20-meter resolution. The LIDAR function detected differential signal return with a 40-meter range accuracy, with a maximum range capability of 640 km, limited by the bit counter in the range return counting clock.

  5. Functional renormalization group approach for inhomogeneous one-dimensional Fermi systems with finite-ranged interactions

    NASA Astrophysics Data System (ADS)

    Weidinger, Lukas; Bauer, Florian; von Delft, Jan

    2017-01-01

    We introduce an equilibrium formulation of the functional renormalization group (fRG) for inhomogeneous systems capable of dealing with spatially finite-ranged interactions. In the general third-order truncated form of fRG, the dependence of the two-particle vertex is described by O (N4) independent variables, where N is the dimension of the single-particle system. In a previous paper [Bauer et al., Phys. Rev. B 89, 045128 (2014), 10.1103/PhysRevB.89.045128], the so-called coupled-ladder approximation (CLA) was introduced and shown to admit a consistent treatment for models with a purely onsite interaction, reducing the vertex to O (N2) independent variables. In this work, we introduce an extended version of this scheme, called the extended coupled ladder approximation (eCLA), which includes a spatially extended feedback between the individual channels, measured by a feedback length L , using O (N2L2) independent variables for the vertex. We apply the eCLA in a static approximation and at zero temperature to three types of one-dimensional model systems, focusing on obtaining the linear response conductance. First, we study a model of a quantum point contact (QPC) with a parabolic barrier top and on-site interactions. In our setup, where the characteristic length lx of the QPC ranges between approximately 4-10 sites, eCLA achieves convergence once L becomes comparable to lx. It also turns out that the additional feedback stabilizes the fRG flow. This enables us, second, to study the geometric crossover between a QPC and a quantum dot, again for a one-dimensional model with on-site interactions. Third, the enlarged feedback also enables the treatment of a finite-ranged interaction extending over up to L sites. Using a simple estimate for the form of such a finite-ranged interaction in a QPC with a parabolic barrier top, we study its effects on the conductance and the density. We find that for low densities and sufficiently large interaction ranges the conductance

  6. Cost and Performance Report - Validation of the Low-Range Differential Pressure (LRDP) Leak Detection System

    NASA Astrophysics Data System (ADS)

    2002-03-01

    The Naval Facilities Engineering Service Center (NFESC) Port Hueneme, California, and its industrial partners, Vista Research, Inc., and Vista Engineering Technologies, L.L.C., have demonstrated and validated (DEM/VAL) an innovative mass-based leak detection system for bulk fuel underground storage tanks (USTs). The Low-Range Differential Pressure (LRDP) system is a computer-controlled system that can reliably detect small leaks in bulk USTs ranging in size from 50,000 gal to 12,500,000 gal. As part of this project, it has been evaluated for performance by an independent third party in a l22.5-ft diameter, 2,100,000-gal tank following EPA's standard test procedures. The LRDP meets monthly monitoring and annual precision (tightness) test regulatory compliance requirements using either a 10-h (overnight) or 24-h test. The LRDP has several significant cost advantages over the internal and external technologies. The cost advantages are realized because of the extremely high performance of the LRDP and the probability of false alarm, the on-line monitoring capability of the LRDP when pennanently installed in a tank, the capability of the system to conduct a short test (an overnight test), and the low recurring costs associated with testing. The cost of a tracer method is expensive because of the high recurring cost of testing. The cost of other mass-based methods is high because of lower performance and the inability to meet both the monthly monitoring and annual precision regulatory requirements with an online system. In addition, the LRDP has the potential to save DOD many hundreds of millions of dollars in terms of clean-up and tank replacement cost avoidance.

  7. Performance analysis of a full-field and full-range swept-source OCT system

    NASA Astrophysics Data System (ADS)

    Krauter, J.; Boettcher, T.; Körner, K.; Gronle, M.; Osten, W.; Passilly, N.; Froehly, L.; Perrin, S.; Gorecki, C.

    2015-09-01

    In recent years, optical coherence tomography (OCT) became gained importance in medical disciplines like ophthalmology, due to its noninvasive optical imaging technique with micrometer resolution and short measurement time. It enables e. g. the measurement and visualization of the depth structure of the retina. In other medical disciplines like dermatology, histopathological analysis is still the gold standard for skin cancer diagnosis. The EU-funded project VIAMOS (Vertically Integrated Array-type Mirau-based OCT System) proposes a new type of OCT system combined with micro-technologies to provide a hand-held, low-cost and miniaturized OCT system. The concept is a combination of full-field and full-range swept-source OCT (SS-OCT) detection in a multi-channel sensor based on a micro-optical Mirau-interferometer array, which is fabricated by means of wafer fabrication. This paper presents the study of an experimental proof-of-concept OCT system as a one-channel sensor with bulk optics. This sensor is a Linnik-interferometer type with similar optical parameters as the Mirau-interferometer array. A commercial wavelength tunable light source with a center wavelength at 845nm and 50nm spectral bandwidth is used with a camera for parallel OCT A-Scan detection. In addition, the reference microscope objective lens of the Linnik-interferometer is mounted on a piezo-actuated phase-shifter. Phase-shifting interferometry (PSI) techniques are applied for resolving the conjugate complex artifact and consequently contribute to an increase of image quality and depth range. A suppression ratio of the complex conjugate term of 36 dB is shown and a system sensitivity greater than 96 dB could be measured.

  8. Chaotic dynamics and thermodynamics of periodic systems with long-range forces

    NASA Astrophysics Data System (ADS)

    Kumar, Pankaj

    Gravitational and electromagnetic interactions form the backbone of our theoretical understanding of the universe. While, in general, such interactions are analytically inexpressible for three-dimensional infinite systems, one-dimensional modeling allows one to treat the long-range forces exactly. Not only are one-dimensional systems of profound intrinsic interest, physicists often rely on one-dimensional models as a starting point in the analysis of their more complicated higher-dimensional counterparts. In the analysis of large systems considered in cosmology and plasma physics, periodic boundary conditions are a natural choice and have been utilized in the study of one dimensional Coulombic and gravitational systems. Such studies often employ numerical simulations to validate the theoretical predictions, and in cases where theoretical relations have not been mathematically formulated, numerical simulations serve as a powerful method in characterizing the system's physical properties. In this dissertation, analytic techniques are formulated to express the exact phase-space dynamics of spatially-periodic one-dimensional Coulombic and gravitational systems. Closed-form versions of the Hamiltonian and the electric field are derived for single-component and two-component Coulombic systems, placing the two on the same footing as the gravitational counterpart. Furthermore, it is demonstrated that a three-body variant of the spatially-periodic Coulombic or gravitational system may be reduced isomorphically to a periodic system of a single particle in a two-dimensional rhombic potential. The analytic results are utilized for developing and implementing efficient computational tools to study the dynamical and the thermodynamic properties of the systems without resorting to numerical approximations. Event-driven algorithms are devised to obtain Lyapunov spectra, radial distribution function, pressure, caloric curve, and Poincare surface of section through an N

  9. Development of a stacked detector system for the x-ray range and its possible applications

    NASA Astrophysics Data System (ADS)

    Maier, Daniel; Limousin, Olivier; Meuris, Aline; Pürckhauer, Sabina; Santangelo, Andrea; Schanz, Thomas; Tenzer, Christoph

    2014-07-01

    We have constructed a stacked detector system operating in the X-ray range from 0.5 keV to 250 keV that consists of a Si-based 64×64 DePFET-Matrix in front of a CdTe hybrid detector called Caliste-64. The setup is operated under laboratory conditions that approximate the expected environment of a space-borne observatory. The DePFET detector is an active pixel matrix that provides high count-rate capabilities with a near Fanolimited spectral resolution at energies up to 15 keV. The Caliste-64 hard X-ray camera consists of a 1mm thick CdTe crystal combined with very compact integrated readout electronics, constituting a high performance spectro-imager with event-triggered time-tagging capability in the energy range between 2 keV and 200 keV. In this combined geometry the DePFET detector works as the Low Energy Detector (LED) while the Caliste-64 - as the High Energy Detector (HED) - detects predominantly the high energetic photons that have passed the LED. In addition to the individual optimization of both detectors, we use the setup to test and optimize the performance of the combined detector system. Side-effects like X-ray fluorescence photons, electrical crosstalk, and mutual heating have negative impacts on the data quality and will be investigated. Besides the primary application as a combined imaging detector system with high sensitivity across a broad energy range, additional applications become feasible. Via the analysis of coincident events in both detectors we can estimate the capabilities of the setup to be used as a Compton camera and as an X-ray polarimeter - both desirable functionalities for use in the lab as well as for future X-ray missions.

  10. A Comprehensive Performance Evaluation of Five Blood Glucose Systems in the Hypo-, Eu-, and Hyperglycemic Range.

    PubMed

    Zijlstra, Eric; Heinemann, Lutz; Fischer, Annelie; Kapitza, Christoph

    2016-11-01

    The objective was to evaluate the performance (in terms of accuracy, precision, and trueness) of 5 CE-certified and commercially available blood glucose (BG) systems (meters plus test strips) using an innovative clinical-experimental study design with a 3-step glucose clamp approach and frequent capillary BG measurements. Sixteen subjects with type 1 diabetes participated in this open label, single center trial. BG was clamped at 3 levels for 60 minutes each: 60-100-200 mg/dL. Medical staff performed regular finger pricks (up to 10 per BG level) to obtain capillary blood samples for paired BG measurements with the 5 BG systems and a laboratory method as comparison. Three BG systems displayed significantly lower mean absolute relative deviations (MARD) (ACCU-Chek® Aviva Nano [5.4%], BGStar® [5.1%], iBGStar® [5.3%]) than 2 others (FreeStyle InsuLinx® [7.7%], OneTouch Verio®IQ [10.3%]). The measurement precision of all BG systems was comparable, but relative bias was also lower for the 3 systems with lower MARD (ACCU-Chek [1.3%], BGStar [-0.9%], iBGStar [1.0%]) compared with the 2 others (FreeStyle [-7.2%], OneTouch [8.9%]). This 3 range glucose clamp approach enables a systematic performance evaluation of BG systems under controlled and reproducible conditions. The random error of the tested BG systems was comparable, but some showed a lower systematic error than others. These BG systems allow an accurate glucose measurement at low, normal and high BG levels. © 2016 Diabetes Technology Society.

  11. A Comprehensive Performance Evaluation of Five Blood Glucose Systems in the Hypo-, Eu-, and Hyperglycemic Range

    PubMed Central

    Zijlstra, Eric; Heinemann, Lutz; Fischer, Annelie; Kapitza, Christoph

    2016-01-01

    Background: The objective was to evaluate the performance (in terms of accuracy, precision, and trueness) of 5 CE-certified and commercially available blood glucose (BG) systems (meters plus test strips) using an innovative clinical-experimental study design with a 3-step glucose clamp approach and frequent capillary BG measurements. Methods: Sixteen subjects with type 1 diabetes participated in this open label, single center trial. BG was clamped at 3 levels for 60 minutes each: 60-100-200 mg/dL. Medical staff performed regular finger pricks (up to 10 per BG level) to obtain capillary blood samples for paired BG measurements with the 5 BG systems and a laboratory method as comparison. Results: Three BG systems displayed significantly lower mean absolute relative deviations (MARD) (ACCU-Chek® Aviva Nano [5.4%], BGStar® [5.1%], iBGStar® [5.3%]) than 2 others (FreeStyle InsuLinx® [7.7%], OneTouch Verio®IQ [10.3%]). The measurement precision of all BG systems was comparable, but relative bias was also lower for the 3 systems with lower MARD (ACCU-Chek [1.3%], BGStar [–0.9%], iBGStar [1.0%]) compared with the 2 others (FreeStyle [–7.2%], OneTouch [8.9%]). Conclusions: This 3 range glucose clamp approach enables a systematic performance evaluation of BG systems under controlled and reproducible conditions. The random error of the tested BG systems was comparable, but some showed a lower systematic error than others. These BG systems allow an accurate glucose measurement at low, normal and high BG levels. PMID:27605592

  12. Cell-veto Monte Carlo algorithm for long-range systems

    NASA Astrophysics Data System (ADS)

    Kapfer, Sebastian C.; Krauth, Werner

    2016-09-01

    We present a rigorous efficient event-chain Monte Carlo algorithm for long-range interacting particle systems. Using a cell-veto scheme within the factorized Metropolis algorithm, we compute each single-particle move with a fixed number of operations. For slowly decaying potentials such as Coulomb interactions, screening line charges allow us to take into account periodic boundary conditions. We discuss the performance of the cell-veto Monte Carlo algorithm for general inverse-power-law potentials, and illustrate how it provides a new outlook on one of the prominent bottlenecks in large-scale atomistic Monte Carlo simulations.

  13. Prospects for TLRS baseline accuracies in the western USA. [transportable laser ranging system

    NASA Technical Reports Server (NTRS)

    Christodoulidis, D.; Smith, D. E.

    1981-01-01

    One of the main goals of the LAGEOS satellite mission is the detection of regional geotectonic movements. A parametric study with the intention to obtain the optimal baseline precision from dynamic solutions of laser ranging to LAGEOS is presented. The varied parameters are: length of reduced arc, number of tracking stations, data noise and rate, biases, refraction errors, system efficiency, gravity model errors in the value of GM. The baseline precisions are 1-10 cm depending upon the set of parameters adopted. General principles obtained are also presented.

  14. Digital I/Q demodulation for KSTAR ion cyclotron range of frequency system

    SciTech Connect

    Wang, S. J.; Kwak, J. G.; Hwang, C. K.

    2009-02-15

    An ion cyclotron range of frequency system requires rf diagnostics for a rf-plasma coupling or for maintaining a correct operation. A detector based on a digital I/Q demodulation technique collects the rf amplitude and phase at the same time without errors from the I/Q imbalance inherent in an analog counterpart. The theory of such a detector was studied and implemented for the first campaign of the KSTAR tokamak. Experimental results of the rf and other diagnostics are presented and discussed.

  15. Digital I/Q demodulation for KSTAR ion cyclotron range of frequency system.

    PubMed

    Wang, S J; Kwak, J G; Hwang, C K

    2009-02-01

    An ion cyclotron range of frequency system requires rf diagnostics for a rf-plasma coupling or for maintaining a correct operation. A detector based on a digital I/Q demodulation technique collects the rf amplitude and phase at the same time without errors from the I/Q imbalance inherent in an analog counterpart. The theory of such a detector was studied and implemented for the first campaign of the KSTAR tokamak. Experimental results of the rf and other diagnostics are presented and discussed.

  16. Development of strapdown inertial navigation system with MEMS sensors, barometric altimeter and ultrasonic range meter

    NASA Astrophysics Data System (ADS)

    Kholopov, I. S.

    2015-10-01

    The results of strapdown inertial navigation system (SINS) tests with 9 degrees of freedom MEMS sensor MPU-9150 (triaxial accelerometer, gyroscope and magnetometer), pressure sensor LPS331 and ultrasonic range meter HC-SR04, implemented on the FPGA Altera Cyclone-II evaluation board DE1 is considered. SINS measures the spatial coordinates and altitude relative to the starting point, the orientation angles and distances to obstacles along the way. It is shown that the relative error of the spatial coordinates estimation does not exceed 1.1% in interval of some minutes.

  17. Cell-veto Monte Carlo algorithm for long-range systems.

    PubMed

    Kapfer, Sebastian C; Krauth, Werner

    2016-09-01

    We present a rigorous efficient event-chain Monte Carlo algorithm for long-range interacting particle systems. Using a cell-veto scheme within the factorized Metropolis algorithm, we compute each single-particle move with a fixed number of operations. For slowly decaying potentials such as Coulomb interactions, screening line charges allow us to take into account periodic boundary conditions. We discuss the performance of the cell-veto Monte Carlo algorithm for general inverse-power-law potentials, and illustrate how it provides a new outlook on one of the prominent bottlenecks in large-scale atomistic Monte Carlo simulations.

  18. 3D indoor modeling using a hand-held embedded system with multiple laser range scanners

    NASA Astrophysics Data System (ADS)

    Hu, Shaoxing; Wang, Duhu; Xu, Shike

    2016-10-01

    Accurate three-dimensional perception is a key technology for many engineering applications, including mobile mapping, obstacle detection and virtual reality. In this article, we present a hand-held embedded system designed for constructing 3D representation of structured indoor environments. Different from traditional vehicle-borne mobile mapping methods, the system presented here is capable of efficiently acquiring 3D data while an operator carrying the device traverses through the site. It consists of a simultaneous localization and mapping(SLAM) module, a 3D attitude estimate module and a point cloud processing module. The SLAM is based on a scan matching approach using a modern LIDAR system, and the 3D attitude estimate is generated by a navigation filter using inertial sensors. The hardware comprises three 2D time-flight laser range finders and an inertial measurement unit(IMU). All the sensors are rigidly mounted on a body frame. The algorithms are developed on the frame of robot operating system(ROS). The 3D model is constructed using the point cloud library(PCL). Multiple datasets have shown robust performance of the presented system in indoor scenarios.

  19. BKT phase transition in a 2D system with long-range dipole-dipole interaction

    NASA Astrophysics Data System (ADS)

    Fedichev, P. O.; Men'shikov, L. I.

    2012-01-01

    We consider phase transitions in 2D XY-like systems with long-range dipole-dipole interactions and demonstrate that BKT-type phase transition always occurs separating the ordered (ferroelectric) and the disordered (paraelectric) phases. The low-temperature phase corresponds to a thermal state with bound vortex-antivortex pairs characterized by linear attraction at large distances. Using the Maier-Schwabl topological charge model, we show that bound vortex pairs polarize and screen the vortex-antivortex interaction, leaving only the logarithmic attraction at sufficiently large separations between the vortices. At higher temperatures the pairs dissociate and the phase transition similar to BKT occurs, though at a larger temperature than in a system without the dipole-dipole interaction.

  20. Nonequilibrium tricritical point in a system with long-range interactions.

    PubMed

    Antoniazzi, Andrea; Fanelli, Duccio; Ruffo, Stefano; Yamaguchi, Yoshiyuki Y

    2007-07-27

    Systems with long-range interactions display a short-time relaxation towards quasistationary states whose lifetime increases with system size. With reference to the Hamiltonian mean field model, we here show that a maximum entropy principle, based on Lynden-Bell's pioneering idea of "violent relaxation," predicts the presence of out-of-equilibrium phase transitions separating the relaxation towards homogeneous (zero magnetization) or inhomogeneous (nonzero magnetization) quasistationary states. When varying the initial condition within a family of "water bags" with different initial magnetization and energy, first- and second-order phase transition lines are found that merge at an out-of-equilibrium tricritical point. Metastability is theoretically predicted and numerically checked around the first-order phase transition line.

  1. Design of a holographic tracking module for long-range retroreflector free-space systems.

    PubMed

    Quintana, C; Erry, G; Gomez, A; Thueux, Y; Faulkner, G E; O'Brien, D C

    2016-09-01

    Weight reduction and low power consumption are key requirements in the next generation of unmanned aerial vehicles (UAVs). To communicate with an operator, a secured link between the UAV and a ground-based station is desirable. To realize these links, retroreflecting free-space optics is potentially attractive as it offers light weight and low complexity at the UAV. However, the base station requires a high-performance tracking module to enable a steady illumination of the UAV retroreflector. In this paper, we present the design and implementation of a tracking system, which consists of coarse tracking and holographic fine tracking modules working cooperatively. Using this system, experimental field trials were carried out by mounting a multiple-quantum-well-based modulated retroreflector on a commercial UAV. A 2 Mbps optical link was achieved with a bit error rate of ∼2×10-4 at a link range of 300 m.

  2. PAR Corneal Topography System (PAR CTS): the clinical application of close-range photogrammetry.

    PubMed

    Belin, M W; Cambier, J L; Nabors, J R; Ratliff, C D

    1995-11-01

    The PAR Corneal Topography System (CTS) is a computer-driven corneal imaging system which uses close-range photogrammetry (rasterphotogrammetry) to measure and produce a topographic map of the corneal surface. The PAR CTS makes direct point-by-point measurements of surface elevation using a stereo-triangulation technique. The CTS uses a grid pattern composed of horizontal and vertical lines spaced about 0.2 mm (200 microns) apart. Each grid intersection comprises a surface feature which can be located in multiple images and used to generate an (x,y,z) coordinate. Unlike placido disc-based videokeratoscopes, the PAR CTS requires neither a smooth reflective surface nor precise spatial alignment for accurate imaging. In addition to surface elevation, the PAR CTS computes axial and tangential curvatures and refractive power. Difference maps are available in all curvatures, refractive power, and in absolute elevation.

  3. A Noise-Robust Continuous Speech Recognition System Using Block-Based Dynamic Range Adjustment

    NASA Astrophysics Data System (ADS)

    Sun, Yiming; Miyanaga, Yoshikazu

    A new approach to speech feature estimation under noise circumstances is proposed in this paper. It is used in noise-robust continuous speech recognition (CSR). As the noise robust techniques in isolated word speech recognition, the running spectrum analysis (RSA), the running spectrum filtering (RSF) and the dynamic range adjustment (DRA) methods have been developed. Among them, only RSA has been applied to a CSR system. This paper proposes an extended DRA for a noise-robust CSR system. In the stage of speech recognition, a continuous speech waveform is automatically assigned to a block defined by a short time length. The extended DRA is applied to these estimated blocks. The average recognition rate of the proposed method has been improved under several different noise conditions. As a result, the recognition rates are improved up to 15% in various noises with 10 dB SNR.

  4. Close range ISR (PRISTA) and close quarters combat (CQC) with unmanned aerial systems (UAS)

    NASA Astrophysics Data System (ADS)

    Maynell, Jon

    2010-04-01

    Ironically, the final frontiers for the UAV (unmanned aerial vehicle) are the closest spaces at hand. There is an urgent operational capability gap in the area of proximate reconnaissance, intelligence, surveillance, and target acquisition (PRISTA) as well as close quarters combats (CQC). Needs for extremely close range functionality in land, sea and urban theaters remain unfilled, largely due to the challenges presented by the maneuverability and silent operating floor required to address these missions. The evolution of small, nimble and inexpensive VTOL UAV assets holds much promise in terms of filling this gap. Just as UAVs have evolved from large manned aircraft, so have MAVs (Micro Aerial Vehicles) evolved from UAVs. As unmanned aviation evolves into aerial robotics, NAV (Nano Aerial Vehicle) research will become the next hotbed of unmanned aerial systems development as these systems continue to mature in response to the need to find robotic replacements for humans in PRISTA, CQC, and many other hazardous duties.

  5. New approach of financial volatility duration dynamics by stochastic finite-range interacting voter system

    NASA Astrophysics Data System (ADS)

    Wang, Guochao; Wang, Jun

    2017-01-01

    We make an approach on investigating the fluctuation behaviors of financial volatility duration dynamics. A new concept of volatility two-component range intensity (VTRI) is developed, which constitutes the maximal variation range of volatility intensity and shortest passage time of duration, and can quantify the investment risk in financial markets. In an attempt to study and describe the nonlinear complex properties of VTRI, a random agent-based financial price model is developed by the finite-range interacting biased voter system. The autocorrelation behaviors and the power-law scaling behaviors of return time series and VTRI series are investigated. Then, the complexity of VTRI series of the real markets and the proposed model is analyzed by Fuzzy entropy (FuzzyEn) and Lempel-Ziv complexity. In this process, we apply the cross-Fuzzy entropy (C-FuzzyEn) to study the asynchrony of pairs of VTRI series. The empirical results reveal that the proposed model has the similar complex behaviors with the actual markets and indicate that the proposed stock VTRI series analysis and the financial model are meaningful and feasible to some extent.

  6. New approach of financial volatility duration dynamics by stochastic finite-range interacting voter system.

    PubMed

    Wang, Guochao; Wang, Jun

    2017-01-01

    We make an approach on investigating the fluctuation behaviors of financial volatility duration dynamics. A new concept of volatility two-component range intensity (VTRI) is developed, which constitutes the maximal variation range of volatility intensity and shortest passage time of duration, and can quantify the investment risk in financial markets. In an attempt to study and describe the nonlinear complex properties of VTRI, a random agent-based financial price model is developed by the finite-range interacting biased voter system. The autocorrelation behaviors and the power-law scaling behaviors of return time series and VTRI series are investigated. Then, the complexity of VTRI series of the real markets and the proposed model is analyzed by Fuzzy entropy (FuzzyEn) and Lempel-Ziv complexity. In this process, we apply the cross-Fuzzy entropy (C-FuzzyEn) to study the asynchrony of pairs of VTRI series. The empirical results reveal that the proposed model has the similar complex behaviors with the actual markets and indicate that the proposed stock VTRI series analysis and the financial model are meaningful and feasible to some extent.

  7. Method to simulate the object tracking with photon-counting laser ranging system

    NASA Astrophysics Data System (ADS)

    Du, Xian; Xing, JiChuan; Huang, Hao

    2015-11-01

    We provide a new method to simulate the process of tracking the noncooperative object that moves beyond visual range with a photon-counting laser ranging system. Based on fundamentals of photon-counting laser ranging techniques and parameters of the experimental prototype, we generate echo events according to their probability. Then, we accumulate the echo data in a certain period of time and accurately extract the object's trajectory with mean-shift and random sample consensus algorithms. Depending on the trajectory during the accumulation period, we predict the relative movement of the object in succeeding cycles by using self-tuning α-β filtering and carefully pick out photon echo signals and apply the polynomial fitting to them to compute the trajectory of the object. The simulation shows that the error between the theoretical trajectory and the extracted trajectory is decreasing all the time, which suggests that we can track the object precisely as the time goes by. The simulation in this paper provides a new way for applications like satellite orientation, identification, troubleshooting, etc.

  8. Lake eutrophication and environmental change: A viability framework for resilience, vulnerability and adaptive capacity

    NASA Astrophysics Data System (ADS)

    Mathias, Jean-Denis; Rougé, Charles; Deffuant, Guillaume

    2013-04-01

    several vulnerability functions, representing for instance social, economic or ecological vulnerability, and each representing the violation of the associated property, but these functions need to be ultimately aggregated as a single indicator. Due to the stochastic nature of the system, there is a range of possible trajectories. Statistics can be derived from the probability distribution of the vulnerability of the trajectories. Dynamic programming methods can then yield the policies which, among available policies, minimize a given trajectory. Thus, this viability framework gives indication on both the possible consequences of a hazard or an environmental change, and on the policies that can mitigate or avert it. It also enables to assess the benefits of extending the set of available policy options, and we define adaptive capacity as the reduction in a given vulnerability statistic due to the introduction of new policy options.

  9. Exact entanglement studies of strongly correlated systems: role of long-range interactions and symmetries of the system.

    PubMed

    Sahoo, Shaon; Goli, V M L Durga Prasad; Ramasesha, S; Sen, Diptiman

    2012-03-21

    We study the bipartite entanglement of strongly correlated systems using exact diagonalization techniques. In particular, we examine how the entanglement changes in the presence of long-range interactions by studying the Pariser-Parr-Pople model with long-range interactions. We compare the results for this model with those obtained for the Hubbard and Heisenberg models with short-range interactions. This study helps us to understand why the density matrix renormalization group (DMRG) technique is so successful even in the presence of long-range interactions. To better understand the behavior of long-range interactions and why the DMRG works well with it, we study the entanglement spectrum of the ground state and a few excited states of finite chains. We also investigate if the symmetry properties of a state vector have any significance in relation to its entanglement. Finally, we make an interesting observation on the entanglement profiles of different states (across the energy spectrum) in comparison with the corresponding profile of the density of states. We use isotropic chains and a molecule with non-Abelian symmetry for these numerical investigations.

  10. Long-range propagation effects observed during acoustic counter battery system tests

    NASA Astrophysics Data System (ADS)

    Velea, Doru; Cardinale, Michael; Torvik, Kevin; LaRow, Andy; Chang, Jay

    2006-05-01

    In March 2005, Planning Systems, Inc. (PSI), Advanced Acoustic Concepts (AAC) and the U.S. Army Research Development and Engineering Center (ARDEC) tested the PSI Acoustic Counter Battery System (ACBS) at the Yuma Proving Ground (YPG). ACBS was designed to acoustically detect and locate mortar fire, and to detect and locate heavy artillery fire out to ranges beyond 12 km. During analysis of the test data, we discovered that long-range sensors were receiving multiple pulses in doublets and triplets from a single shot. Additionally, we observed that the leading pulses were arriving earlier than anticipated by surface speed of sound calculations. The analysis team modeled the atmosphere recorded during the test and identified the possible causes of multiple arrivals by modeling the supersonic projectile trajectory and by using Green's Function Parabolic Equation numerical techniques to propagate recorded pulses from the source to receivers. The lessons learned will be applied to adjust the signal processing algorithms in the ACBS. This paper describes the test setup and reports the results of the analysis.

  11. Out-of-equilibrium phase re-entrance(s) in long-range interacting systems

    NASA Astrophysics Data System (ADS)

    Staniscia, F.; Chavanis, P. H.; de Ninno, G.; Fanelli, D.

    2009-08-01

    Systems with long-range interactions display a short-time relaxation toward quasistationary states (QSSs) whose lifetime increases with system size. The application of Lynden-Bell’s theory of “violent relaxation” to the Hamiltonian Mean Field model leads to the prediction of out-of-equilibrium first- and second-order phase transitions between homogeneous (zero magnetization) and inhomogeneous (nonzero magnetization) QSSs, as well as an interesting phenomenon of phase re-entrances. We compare these theoretical predictions with direct N -body numerical simulations. We confirm the existence of phase re-entrance in the typical parameter range predicted from Lynden-Bell’s theory, but also show that the picture is more complicated than initially thought. In particular, we exhibit the existence of secondary re-entrant phases: we find unmagnetized states in the theoretically magnetized region as well as persisting magnetized states in the theoretically unmagnetized region. We also report the existence of a region with negative specific heats for QSSs both in the numerical and analytical caloric curves.

  12. Northwest Basin and Range tectonic deformation observed with the Global Positioning System, 1999-2003

    USGS Publications Warehouse

    Hammond, W.C.; Thatcher, W.

    2005-01-01

    We use geodetic velocities obtained with the Global Positioning System (GPS) to quantify tectonic deformation of the northwest Basin and Range province of the western United States. The results are based on GPS data collected in 1999 and 2003 across five new quasi-linear networks in northern Nevada, northeast California, and southeast Oregon. The velocities show ???3 mm/yr westward movement of northern Nevada with respect to stable North America. West of longitude 119??W the velocities increase and turn northwest, parallel to Sierra Nevada/Great Valley microplate motion, and similar to velocities previously obtained to the south. The observations are explained by a kinematic model with three domains that rotate around Euler poles in eastern Oregon and western Idaho. Northeast California experiences internal dextral shear deformation (11.2 ?? 3.6 nstrain/yr) subparallel to Pacific/North America motion. Relative motions of the domains imply 2-5 mm/yr approximately east-west extension in northwest Nevada and 1-4 mm/yr approximately north-south contraction near the California/Oregon border. The northward decreasing approximately east-west extension in northwest Nevada is consistent with the northern termination of Basin and Range deformation, faulting and characteristic topography. No significant extension is detected in the Oregon Basin and Range. The Oregon Cascade arc moves north at ???3.5 mm/yr and is possibly influenced by the approximately eastward motion of the Juan de Fuca plate. These results disagree with secular northwest trenchward motion of the Oregon forearc inferred from paleomagnetic rotations. South of latitude 43??, however, trenchward motion exists and is consistent with block rotations, approximately east-west Basin and Range extension, and northwest Sierra Nevada translation. Copyright 2005 by the American Geophysical Union.

  13. NASA's Photon-Counting SLR2000 Satellite Laser Ranging System: Progress and Applications

    NASA Technical Reports Server (NTRS)

    Degnan, John J.; McGarry, Jan; Zagwodzki, Thomas; Donovan, Howard; Patterson, Don; Steggerda, Charles; Mallama, Anthony; Cheek, Jack

    2002-01-01

    NASA's new unmanned SLR2000 system is designed to track, with millimeter precision and using single photon returns, a constellation of roughly 24 retroreflector-equipped satellites, which range in altitude from about 300 km to 20,000 km. Totally autonomous operation and a common engineering configuration are expected to greatly reduce station operations costs relative to NASA's current manned systems. The system has also been designed with a goal of significantly lowering replication costs. All of the prototype components and subsystems have been completed and tested and have substantially met the original specifications. The prototype system is presently undergoing final integration and testing in a dedicated shelter with an azimuth tracking dome synchronized to the optical tracking mount. The facility also features a number of security features such as security cameras and sensors designed to detect power or thermal control problems or entry by unauthorized personnel. Field tests are in progress. The present paper provides an overview of the various subsystems and test results to date. The meteorological subsystem, which has operated successfully in the field for almost three years, consists of several sensors which measure: (1) pressure, temperature, and relative humidity; (2) wind speed and direction; (3) ground visibility and precipitation; and (4) local cloud cover as a function of station azimuth and elevation (day and night). A "pseudo-operator" software program interprets the sensor readings and modifies satellite tracking priorities based on local meteorological conditions.

  14. Bore-Sight Calibration of Multiple Laser Range Finders for Kinematic 3D Laser Scanning Systems.

    PubMed

    Jung, Jaehoon; Kim, Jeonghyun; Yoon, Sanghyun; Kim, Sangmin; Cho, Hyoungsig; Kim, Changjae; Heo, Joon

    2015-05-04

    The Simultaneous Localization and Mapping (SLAM) technique has been used for autonomous navigation of mobile systems; now, its applications have been extended to 3D data acquisition of indoor environments. In order to reconstruct 3D scenes of indoor space, the kinematic 3D laser scanning system, developed herein, carries three laser range finders (LRFs): one is mounted horizontally for system-position correction and the other two are mounted vertically to collect 3D point-cloud data of the surrounding environment along the system's trajectory. However, the kinematic laser scanning results can be impaired by errors resulting from sensor misalignment. In the present study, the bore-sight calibration of multiple LRF sensors was performed using a specially designed double-deck calibration facility, which is composed of two half-circle-shaped aluminum frames. Moreover, in order to automatically achieve point-to-point correspondences between a scan point and the target center, a V-shaped target was designed as well. The bore-sight calibration parameters were estimated by a constrained least squares method, which iteratively minimizes the weighted sum of squares of residuals while constraining some highly-correlated parameters. The calibration performance was analyzed by means of a correlation matrix. After calibration, the visual inspection of mapped data and residual calculation confirmed the effectiveness of the proposed calibration approach.

  15. NASA's Photon-Counting SLR2000 Satellite Laser Ranging System: Progress and Applications

    NASA Technical Reports Server (NTRS)

    Degnan, John J.; McGarry, Jan; Zagwodzki, Thomas; Donovan, Howard; Patterson, Don; Steggerda, Charles; Mallama, Anthony; Cheek, Jack

    2002-01-01

    NASA's new unmanned SLR2000 system is designed to track, with millimeter precision and using single photon returns, a constellation of roughly 24 retroreflector-equipped satellites, which range in altitude from about 300 km to 20,000 km. Totally autonomous operation and a common engineering configuration are expected to greatly reduce station operations costs relative to NASA's current manned systems. The system has also been designed with a goal of significantly lowering replication costs. All of the prototype components and subsystems have been completed and tested and have substantially met the original specifications. The prototype system is presently undergoing final integration and testing in a dedicated shelter with an azimuth tracking dome synchronized to the optical tracking mount. The facility also features a number of security features such as security cameras and sensors designed to detect power or thermal control problems or entry by unauthorized personnel. Field tests are in progress. The present paper provides an overview of the various subsystems and test results to date. The meteorological subsystem, which has operated successfully in the field for almost three years, consists of several sensors which measure: (1) pressure, temperature, and relative humidity; (2) wind speed and direction; (3) ground visibility and precipitation; and (4) local cloud cover as a function of station azimuth and elevation (day and night). A "pseudo-operator" software program interprets the sensor readings and modifies satellite tracking priorities based on local meteorological conditions.

  16. A Plasmid-Transposon Hybrid Mutagenesis System Effective in a Broad Range of Enterobacteria

    PubMed Central

    Monson, Rita; Smith, Debra S.; Matilla, Miguel A.; Roberts, Kevin; Richardson, Elizabeth; Drew, Alison; Williamson, Neil; Ramsay, Josh; Welch, Martin; Salmond, George P. C.

    2015-01-01

    Random transposon mutagenesis is a powerful technique used to generate libraries of genetic insertions in many different bacterial strains. Here we develop a system facilitating random transposon mutagenesis in a range of different Gram-negative bacterial strains, including Pectobacterium atrosepticum, Citrobacter rodentium, Serratia sp. ATCC39006, Serratia plymuthica, Dickeya dadantii, and many more. Transposon mutagenesis was optimized in each of these strains and three studies are presented to show the efficacy of this system. Firstly, the important agricultural pathogen D. dadantii was mutagenized. Two mutants that showed reduced protease production and one mutant producing the previously cryptic pigment, indigoidine, were identified and characterized. Secondly, the enterobacterium, Serratia sp. ATCC39006 was mutagenized and mutants incapable of producing gas vesicles, proteinaceous intracellular organelles, were identified. One of these contained a β-galactosidase transcriptional fusion within the gene gvpA1, essential for gas vesicle production. Finally, the system was used to mutate the biosynthetic gene clusters of the antifungal, anti-oomycete and anticancer polyketide, oocydin A, in the plant-associated enterobacterium, Dickeya solani MK10. The mutagenesis system was developed to allow easy identification of transposon insertion sites by sequencing, after facile generation of a replicon encompassing the transposon and adjacent DNA, post-excision. Furthermore, the system can also create transcriptional fusions with either β-galactosidase or β-glucuronidase as reporters, and exploits a variety of drug resistance markers so that multiple selectable fusions can be generated in a single strain. This system of various transposons has wide utility and can be combined in many different ways. PMID:26733980

  17. A Plasmid-Transposon Hybrid Mutagenesis System Effective in a Broad Range of Enterobacteria.

    PubMed

    Monson, Rita; Smith, Debra S; Matilla, Miguel A; Roberts, Kevin; Richardson, Elizabeth; Drew, Alison; Williamson, Neil; Ramsay, Josh; Welch, Martin; Salmond, George P C

    2015-01-01

    Random transposon mutagenesis is a powerful technique used to generate libraries of genetic insertions in many different bacterial strains. Here we develop a system facilitating random transposon mutagenesis in a range of different Gram-negative bacterial strains, including Pectobacterium atrosepticum, Citrobacter rodentium, Serratia sp. ATCC39006, Serratia plymuthica, Dickeya dadantii, and many more. Transposon mutagenesis was optimized in each of these strains and three studies are presented to show the efficacy of this system. Firstly, the important agricultural pathogen D. dadantii was mutagenized. Two mutants that showed reduced protease production and one mutant producing the previously cryptic pigment, indigoidine, were identified and characterized. Secondly, the enterobacterium, Serratia sp. ATCC39006 was mutagenized and mutants incapable of producing gas vesicles, proteinaceous intracellular organelles, were identified. One of these contained a β-galactosidase transcriptional fusion within the gene gvpA1, essential for gas vesicle production. Finally, the system was used to mutate the biosynthetic gene clusters of the antifungal, anti-oomycete and anticancer polyketide, oocydin A, in the plant-associated enterobacterium, Dickeya solani MK10. The mutagenesis system was developed to allow easy identification of transposon insertion sites by sequencing, after facile generation of a replicon encompassing the transposon and adjacent DNA, post-excision. Furthermore, the system can also create transcriptional fusions with either β-galactosidase or β-glucuronidase as reporters, and exploits a variety of drug resistance markers so that multiple selectable fusions can be generated in a single strain. This system of various transposons has wide utility and can be combined in many different ways.

  18. Gaussian approach for phase ordering in nonconserved scalar systems with long-range interactions

    NASA Astrophysics Data System (ADS)

    Filipe, J. A. N.; Bray, A. J.

    1995-01-01

    We have applied the Gaussian auxiliary field method to a nonconserved scalar system with attractive long-range interactions, falling off with distance as 1/rd+σ, where d is the spatial dimension and 0<σ<2. This study provides a test bed for the approach and shows some of the difficulties encountered in constructing a closed equation for the pair correlation function. For the relation φ=φ(m) between the order parameter φ and the auxiliary field m, the usual choice of the equilibrium interfacial profile is made. The equation obtained for the equal-time two-point correlation function is studied in the limiting cases of small and large values of the scaling variable. A Porod regime at short distance and an asymptotic power-law decay at large distance are obtained. The theory is not, however, consistent with the expected growth law and attempts to retrieve the correct growth lead to inconsistencies. These results indicate a failure of the Gaussian assumption for this system, when used in the context of the bulk dynamics. This statement holds at least within the present form of the mapping φ=φ(m), which appears to be the most natural choice, as well as the one consistent with the emergence of the Porod regime. By contrast, Ohta and Hayakawa have recenlty succeeded in implementing a Gaussian approach based on the interfacial dynamics of this system [Physica A 204, 482 (1994)]. This clearly suggests that, beyond the simplicity of short-range ``model A'' dynamics, a Gaussian approach can only capture the essential physical features if the crucial role of wall motion in domain growth is explicitly considered.

  19. Navigation for space shuttle approach and landing using an inertial navigation system augmented by data from a precision ranging system or a microwave scan beam landing guidance system

    NASA Technical Reports Server (NTRS)

    Mcgee, L. A.; Smith, G. L.; Hegarty, D. M.; Merrick, R. B.; Carson, T. M.; Schmidt, S. F.

    1970-01-01

    A preliminary study has been made of the navigation performance which might be achieved for the high cross-range space shuttle orbiter during final approach and landing by using an optimally augmented inertial navigation system. Computed navigation accuracies are presented for an on-board inertial navigation system augmented (by means of an optimal filter algorithm) with data from two different ground navigation aids; a precision ranging system and a microwave scanning beam landing guidance system. These results show that augmentation with either type of ground navigation aid is capable of providing a navigation performance at touchdown which should be adequate for the space shuttle. In addition, adequate navigation performance for space shuttle landing is obtainable from the precision ranging system even with a complete dropout of precision range measurements as much as 100 seconds before touchdown.

  20. Scintillator-CCD camera system light output response to dosimetry parameters for proton beam range measurement

    NASA Astrophysics Data System (ADS)

    Daftari, Inder K.; Castaneda, Carlos M.; Essert, Timothy; Phillips, Theodore L.; Mishra, Kavita K.

    2012-09-01

    The purpose of this study is to investigate the luminescence light output response in a plastic scintillator irradiated by a 67.5 MeV proton beam using various dosimetry parameters. The relationship of the visible scintillator light with the beam current or dose rate, aperture size and the thickness of water in the water-column was studied. The images captured on a CCD camera system were used to determine optimal dosimetry parameters for measuring the range of a clinical proton beam. The method was developed as a simple quality assurance tool to measure the range of the proton beam and compare it to (a) measurements using two segmented ionization chambers and water column between them, and (b) with an ionization chamber (IC-18) measurements in water. We used a block of plastic scintillator that measured 5×5×5 cm3 to record visible light generated by a 67.5 MeV proton beam. A high-definition digital video camera Moticam 2300 connected to a PC via USB 2.0 communication channel was used to record images of scintillation luminescence. The brightness of the visible light was measured while changing beam current and aperture size. The results were analyzed to obtain the range and were compared with the Bragg peak measurements with an ionization chamber. The luminescence light from the scintillator increased linearly with the increase of proton beam current. The light output also increased linearly with aperture size. The relationship between the proton range in the scintillator and the thickness of the water column showed good linearity with a precision of 0.33 mm (SD) in proton range measurement. For the 67.5 MeV proton beam utilized, the optimal parameters for scintillator light output response were found to be 15 nA (16 Gy/min) and an aperture size of 15 mm with image integration time of 100 ms. The Bragg peak depth brightness distribution was compared with the depth dose distribution from ionization chamber measurements and good agreement was observed. The peak